73 files changed, 25657 insertions, 27 deletions

diff --git a/ObsoleteFiles.inc b/ObsoleteFiles.inc
index dcc4c4c0c3c4f..9f3fbb9a848de 100644
--- a/ObsoleteFiles.inc
+++ b/ObsoleteFiles.inc
@@ -38,29 +38,6 @@
 #   xargs -n1 | sort | uniq -d;
 # done
 
-# 20131015: removal of RCS from base
-OLD_FILES+=usr/bin/ci
-OLD_FILES+=usr/bin/co
-OLD_FILES+=usr/bin/ident
-OLD_FILES+=usr/bin/merge
-OLD_FILES+=usr/bin/rcs
-OLD_FILES+=usr/bin/rcsclean
-OLD_FILES+=usr/bin/rcsdiff
-OLD_FILES+=usr/bin/rcsfreeze
-OLD_FILES+=usr/bin/rcsmerge
-OLD_FILES+=usr/bin/rlog
-OLD_FILES+=usr/share/man/man1/ci.1.gz
-OLD_FILES+=usr/share/man/man1/co.1.gz
-OLD_FILES+=usr/share/man/man1/ident.1.gz
-OLD_FILES+=usr/share/man/man1/merge.1.gz
-OLD_FILES+=usr/share/man/man1/rcs.1.gz
-OLD_FILES+=usr/share/man/man1/rcsclean.1.gz
-OLD_FILES+=usr/share/man/man1/rcsdiff.1.gz
-OLD_FILES+=usr/share/man/man1/rcsfreeze.1.gz
-OLD_FILES+=usr/share/man/man1/rcsintro.1.gz
-OLD_FILES+=usr/share/man/man1/rcsmerge.1.gz
-OLD_FILES+=usr/share/man/man1/rlog.1.gz
-OLD_FILES+=usr/share/man/man5/rcsfile.5.gz
 # 20131001: ar and ranlib from binutils not used
 OLD_FILES+=usr/bin/gnu-ar
 OLD_FILES+=usr/bin/gnu-ranlib
diff --git a/UPDATING b/UPDATING
index e9f0251e068f0..067f5a01b716b 100644
--- a/UPDATING
+++ b/UPDATING
@@ -31,10 +31,6 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 10.x IS SLOW:
 	disable the most expensive debugging functionality run
 	"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
 
-20131006:
-	RCS has been removed from the base system.  If you need RCS
-	install either devel/rcs or devel/rcs57.
-
 20130930:
 	BIND has been removed from the base system.  If all you need
 	is a local resolver, simply enable and start the local_unbound
diff --git a/gnu/usr.bin/Makefile b/gnu/usr.bin/Makefile
index 8ece263b33ed6..663107c3947e5 100644
--- a/gnu/usr.bin/Makefile
+++ b/gnu/usr.bin/Makefile
@@ -12,6 +12,7 @@ SUBDIR= ${_binutils} \
 	${_gperf} \
 	grep \
 	${_groff} \
+	${_rcs} \
 	sdiff \
 	send-pr \
 	${_texinfo}
@@ -31,6 +32,10 @@ _dtc=		dtc
 _texinfo=	texinfo
 .endif
 
+.if ${MK_RCS} != "no"
+_rcs=		rcs
+.endif
+
 .if ${MK_BINUTILS} != "no"
 _binutils=	binutils
 .endif
diff --git a/gnu/usr.bin/rcs/CREDITS b/gnu/usr.bin/rcs/CREDITS
new file mode 100644
index 0000000000000..589e8b6850919
--- /dev/null
+++ b/gnu/usr.bin/rcs/CREDITS
@@ -0,0 +1,24 @@
+RCS was designed and built by Walter F. Tichy of Purdue University.
+RCS version 3 was released in 1983.
+
+Adam Hammer, Thomas Narten, and Daniel Trinkle of Purdue supported RCS through
+version 4.3, released in 1990.  Guy Harris of Sun contributed many porting
+fixes.  Paul Eggert of System Development Corporation contributed bug fixes
+and tuneups.  Jay Lepreau contributed 4.3BSD support.
+
+Paul Eggert of Twin Sun wrote the changes for RCS versions 5.5 and 5.6 (1991).
+Rich Braun of Kronos and Andy Glew of Intel contributed ideas for new options.
+Bill Hahn of Stratus contributed ideas for setuid support.
+Ideas for piece tables came from Joe Berkovitz of Stratus and Walter F. Tichy.
+Matt Cross of Stratus contributed test case ideas.
+Adam Hammer of Purdue QAed.
+
+Paul Eggert wrote most of the changes for this version of RCS,
+currently in beta test.  K. Richard Pixley of Cygnus Support
+contributed several bug fixes.  Robert Lupton of Princeton
+and Daniel Trinkle contributed ideas for $Name expansion.
+Brendan Kehoe of Cygnus Support suggested rlog's -N option.
+Paul D. Smith of Data General suggested improvements in option
+and error processing.  Adam Hammer of Purdue QAed.
+
+$FreeBSD$
diff --git a/gnu/usr.bin/rcs/Makefile b/gnu/usr.bin/rcs/Makefile
new file mode 100644
index 0000000000000..4a9fd0838a07d
--- /dev/null
+++ b/gnu/usr.bin/rcs/Makefile
@@ -0,0 +1,3 @@
+SUBDIR= lib ci co ident merge rcs rcsclean rcsdiff rcsmerge rlog rcsfreeze
+
+.include <bsd.subdir.mk>
diff --git a/gnu/usr.bin/rcs/Makefile.inc b/gnu/usr.bin/rcs/Makefile.inc
new file mode 100644
index 0000000000000..a46437ad8c824
--- /dev/null
+++ b/gnu/usr.bin/rcs/Makefile.inc
@@ -0,0 +1,3 @@
+# $FreeBSD$
+
+LIBRCS=	${.OBJDIR}/../lib/librcs.a
diff --git a/gnu/usr.bin/rcs/NEWS b/gnu/usr.bin/rcs/NEWS
new file mode 100644
index 0000000000000..99208064bd329
--- /dev/null
+++ b/gnu/usr.bin/rcs/NEWS
@@ -0,0 +1,548 @@
+Recent changes to RCS (and possible future changes)
+
+ $FreeBSD$
+
+	Copyright 1991, 1992, 1993, 1994, 1995 Paul Eggert
+	Distributed under license by the Free Software Foundation, Inc.
+
+	This file is part of RCS.
+
+	RCS is free software; you can redistribute it and/or modify it
+	under the terms of the GNU General Public License as published
+	by the Free Software Foundation; either version 2, or (at your
+	option) any later version.
+
+	RCS is distributed in the hope that it will be useful, but
+	WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with RCS; see the file COPYING.
+	If not, write to the Free Software Foundation,
+	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+	Report problems and direct all questions to:
+
+		rcs-bugs@cs.purdue.edu
+
+
+Here is a brief summary of user-visible changes since 5.6.
+
+  New options:
+    `-kb' supports binary files.
+    `-T' preserves the modification time of RCS files.
+    `-V' prints the version number.
+    `-zLT' causes RCS to use local time in working files and logs.
+    `rcsclean -n' outputs what rcsclean would do, without actually doing it.
+    `rlog -N' omits symbolic names.
+  There is a new keyword `Name'.
+  Inserted log lines now have the same prefix as the preceding `$Log' line.
+
+Most changes for RCS version 5.7 are to fix bugs and improve portability.
+RCS now conforms to GNU configuration standards and to Posix 1003.1b-1993.
+
+
+Features new to RCS version 5.7, and possibly incompatible
+in minor ways with previous practice, include:
+
+  Inserted log lines now have the same prefix as the preceding `$Log' line.
+  E.g. if a $Log line starts with `// $Log', log lines are prefixed with `// '.
+  RCS still records the (now obsolescent) comment leader inside RCS files,
+  but it ignores the comment leader unless it is emulating older RCS versions.
+  If you plan to access a file with both old and new versions of RCS,
+  make sure its comment leader matches its `$Log' line prefix.
+  For backwards compatibility with older versions of RCS,
+  if the log prefix is `/*' or `(*' surrounded by optional white space,
+  inserted log lines contain ` *' instead of `/*' or `(*';
+  however, this usage is obsolescent and should not be relied on.
+
+  $Log string `Revision' times now use the same format as other times.
+
+  Log lines are now inserted even if -kk is specified; this simplifies merging.
+
+  ci's -rR option (with a nonempty R) now just specifies a revision number R.
+  In some beta versions, it also reestablished the default behavior of
+  releasing a lock and removing the working file.
+  Now, only the bare -r option does this.
+
+  With an empty extension, any appearance of a directory named `RCS'
+  in a pathname identifies the pathname as being that of an RCS file.
+  For example, `a/RCS/b/c' is now an RCS file with an empty extension.
+  Formerly, `RCS' had to be the last directory in the pathname.
+
+  rlog's -d option by default now uses exclusive time ranges.
+  E.g. `rlog -d"<T"' now excludes revisions whose times equal T exactly.
+  Use `rlog -d"<=T"' to get the old behavior.
+
+  merge now takes up to three -L options, one for each input file.
+  Formerly, it took at most two -L options, for the 1st and 3rd input files.
+
+  `rcs' now requires at least one option; this is for future expansion.
+
+Other features new to RCS version 5.7 include:
+
+  merge and rcsmerge now pass -A, -E, and -e options to the subsidiary diff3.
+
+  rcs -kb acts like rcs -ko, except it uses binary I/O on working files.
+  This makes no difference under Posix or Unix, but it does matter elsewhere.
+  With -kb in effect, rcsmerge refuses to merge;
+  this avoids common problems with CVS merging.
+
+  The following is for future use by GNU Emacs 19's version control package:
+
+    rcs's new -M option causes it to not send mail when you break somebody
+    else's lock.  This is not meant for casual use; see rcs(1).
+
+    ci's new -i option causes an error if the RCS file already exists.
+    Similarly, -j causes an error if the RCS file does not already exist.
+
+  The new keyword `Name' is supported; its value is the name, if any,
+  used to check out the revision.  E.g. `co -rN foo' causes foo's
+  $Name...$ keyword strings to end in `: N $'.
+
+  The new -zZONE option causes RCS to output dates and times using ISO 8601
+  format with ZONE as the time zone, and to use ZONE as the default time
+  zone for input.  Its most common use is the -zLT option, which causes RCS
+  to use local time externally.  You can also specify foreign time zones;
+  e.g. -z+05:30 causes RCS to use India time (5 hours 30 minutes east of UTC).
+  This option does not affect RCS files themselves, which always use UTC;
+  it affects only output (e.g. rlog output, keyword expansion, diff -c times)
+  and interpretation of options (e.g. the -d option of ci, co, and rlog).
+  Bare -z restores the default behavior of UTC with no time zone indication,
+  and the traditional RCS date separator `/' instead of the ISO 8601 `-'.
+  RCSINIT may contain a -z option.  ci -k parses UTC offsets.
+
+  The new -T option of ci, co, rcs, and rcsclean preserves the modification
+  time of the RCS file unless a revision is added or removed.
+  ci -T sets the RCS file's modification time to the new revision's time
+  if the former precedes the latter and there is a new revision;
+  otherwise, it preserves the RCS file's modification time.
+  Use this option with care, as it can confuse `make'; see ci(1).
+
+  The new -N option of rlog omits symbolic names from the output.
+
+  A revision number that starts with `.' is considered to be relative to
+  the default branch (normally the trunk).  A branch number followed by `.'
+  stands for the last revision on that branch.
+
+  If someone else already holds the lock, rcs -l now asks whether you want
+  to break it, instead of immediately reporting an error.
+
+  ci now always unlocks a revision like 3.5 if you check in a revision
+  like 3.5.2.1 that is the first of a new branch of that revision.
+  Formerly it was inconsistent.
+
+  File names may now contain tab, newline, space, and '$'.
+  They are represented in keyword strings with \t, \n, \040, and \044.
+  \ in a file name is now represented by \\ in a keyword string.
+
+  Identifiers may now start with a digit and (unless they are symbolic names)
+  may contain `.'.  This permits author names like `john.doe' and `4tran'.
+
+  A bare -V option now prints the current version number.
+
+  rcsdiff outputs more readable context diff headers if diff -L works.
+
+  rcsdiff -rN -rN now suppresses needless checkout and comparison
+  of identical revisions.
+
+  Error messages now contain the names of files to which they apply.
+
+  Mach style memory mapping is now supported.
+
+  The installation procedure now conforms to the GNU coding standards.
+
+  When properly configured, RCS now strictly conforms to Posix 1003.1b-1993.
+
+
+Features new to RCS version 5.6 include:
+
+  Security holes have been plugged; setgid use is no longer supported.
+
+  co can retrieve old revisions much more efficiently.
+  To generate the Nth youngest revision on the trunk,
+  the old method used up to N passes through copies of the working file;
+  the new method uses a piece table to generate the working file in one pass.
+
+  When ci finds no changes in the working file,
+  it automatically reverts to the previous revision unless -f is given.
+
+  RCS follows symbolic links to RCS files instead of breaking them,
+  and warns when it breaks hard links to RCS files.
+
+  `$' stands for the revision number taken from working file keyword strings.
+  E.g. if F contains an Id keyword string,
+  `rcsdiff -r$ F' compares F to its checked-in revision, and
+  `rcs -nL:$ F' gives the symbolic name L to F's revision.
+
+  co and ci's new -M option sets the modification time
+  of the working file to be that of the revision.
+  Without -M, ci now tries to avoid changing the working file's
+  modification time if its contents are unchanged.
+
+  rcs's new -m option changes the log message of an old revision.
+
+  RCS is portable to hosts that do not permit `,' in filenames.
+  (`,' is not part of the Posix portable filename character set.)
+  A new -x option specifies extensions other than `,v' for RCS files.
+  The Unix default is `-x,v/', so that the working file `w' corresponds
+  to the first file in the list `RCS/w,v', `w,v', `RCS/w' that works.
+  The non-Unix default is `-x', so that only `RCS/w' is tried.
+  Eventually, the Unix default should change to `-x/,v'
+  to encourage interoperability among all Posix hosts.
+
+  A new RCSINIT environment variable specifies defaults for options like -x.
+
+  The separator for revision ranges has been changed from `-' to `:', because
+  the range `A-B' is ambiguous if `A', `B' and `A-B' are all symbolic names.
+  E.g. the old `rlog -r1.5-1.7' is now `rlog -r1.5:1.7'; ditto for `rcs -o'.
+  For a while RCS will still support (but warn about) the old `-' separator.
+
+  RCS manipulates its lock files using a method that is more reliable under NFS.
+
+
+Features new to RCS version 5 include:
+
+  RCS can check in arbitrary files, not just text files, if diff -a works.
+  RCS can merge lines containing just a single `.' if diff3 -m works.
+  GNU diff supports the -a and -m options.
+
+  RCS can now be used as a setuid program.
+  See ci(1) for how users can employ setuid copies of ci, co, and rcsclean.
+  Setuid privileges yield extra security if the effective user owns RCS files
+  and directories, and if only the effective user can write RCS directories.
+  RCS uses the real user for all accesses other than writing RCS directories.
+  As described in ci(1), there are three levels of setuid support.
+
+    1.  Setuid works fully if the seteuid() system call lets any
+    process switch back and forth between real and effective users,
+    as specified in Posix 1003.1a Draft 5.
+
+    2.  On hosts with saved setuids (a Posix 1003.1-1990 option) and without
+    a modern seteuid(), setuid works unless the real or effective user is root.
+
+    3.  On hosts that lack both modern seteuid() and saved setuids,
+    setuid does not work, and RCS uses the effective user for all accesses;
+    formerly it was inconsistent.
+
+  New options to co, rcsdiff, and rcsmerge give more flexibility to keyword
+  substitution.
+
+    -kkv substitutes the default `$Keyword: value $' for keyword strings.
+    However, a locker's name is inserted only as a file is being locked,
+    i.e. by `ci -l' and `co -l'.  This is normally the default.
+
+    -kkvl acts like -kkv, except that a locker's name is always inserted
+    if the given revision is currently locked.  This was the default in
+    version 4.  It is now the default only with when using rcsdiff to
+    compare a revision to a working file whose mode is that of a file
+    checked out for changes.
+
+    -kk substitutes just `$Keyword$', which helps to ignore keyword values
+    when comparing revisions.
+
+    -ko retrieves the old revision's keyword string, thus bypassing keyword
+    substitution.
+
+    -kv retrieves just `value'.  This can ease the use of keyword values, but
+    it is dangerous because it causes RCS to lose track of where the keywords
+    are, so for safety the owner write permission of the working file is
+    turned off when -kv is used; to edit the file later, check it out again
+    without -kv.
+
+  rcs -ko sets the default keyword substitution to be in the style of co -ko,
+  and similarly for the other -k options.  This can be useful with file
+  formats that cannot tolerate changing the lengths of keyword strings.
+  However it also renders a RCS file readable only by RCS version 5 or later.
+  Use rcs -kkv to restore the usual default substitution.
+
+  RCS can now be used by development groups that span time zone boundaries.
+  All times are now displayed in UTC, and UTC is the default time zone.
+  To use local time with co -d, append ` LT' to the time.
+  When interchanging RCS files with sites running older versions of RCS,
+  time stamp discrepancies may prevent checkins; to work around this,
+  use `ci -d' with a time slightly in the future.
+
+  Dates are now displayed using four-digit years, not two-digit years.
+  Years given in -d options must now have four digits.
+  This change is required for RCS to continue to work after 1999/12/31.
+  The form of dates in version 5 RCS files will not change until 2000/01/01,
+  so in the meantime RCS files can still be interchanged with sites
+  running older versions of RCS.  To make room for the longer dates,
+  rlog now outputs `lines: +A -D' instead of `lines added/del: A/D'.
+
+  To help prevent diff programs that are broken or have run out of memory
+  from trashing an RCS file, ci now checks diff output more carefully.
+
+  ci -k now handles the Log keyword, so that checking in a file
+  with -k does not normally alter the file's contents.
+
+  RCS no longer outputs white space at the ends of lines
+  unless the original working file had it.
+  For consistency with other keywords,
+  a space, not a tab, is now output after `$Log:'.
+  Rlog now puts lockers and symbolic names on separate lines in the output
+  to avoid generating lines that are too long.
+  A similar fix has been made to lists in the RCS files themselves.
+
+  RCS no longer outputs the string `Locker: ' when expanding Header or Id
+  keywords.  This saves space and reverts back to version 3 behavior.
+
+  The default branch is not put into the RCS file unless it is nonempty.
+  Therefore, files generated by RCS version 5 can be read by RCS version 3
+  unless they use the default branch feature introduced in version 4.
+  This fixes a compatibility problem introduced by version 4.
+
+  RCS can now emulate older versions of RCS; see `co -V'.
+  This may be useful to overcome compatibility problems
+  due to the above changes.
+
+  Programs like Emacs can now interact with RCS commands via a pipe:
+  the new -I option causes ci, co, and rcs to run interactively,
+  even if standard input is not a terminal.
+  These commands now accept multiple inputs from stdin separated by `.' lines.
+
+  ci now silently ignores the -t option if the RCS file already exists.
+  This simplifies some shell scripts and improves security in setuid sites.
+
+  Descriptive text may be given directly in an argument of the form -t-string.
+
+  The character set for symbolic names has been upgraded
+  from Ascii to ISO 8859.
+
+  rcsdiff now passes through all options used by GNU diff;
+  this is a longer list than 4.3BSD diff.
+
+  merge's new -L option gives tags for merge's overlap report lines.
+  This ability used to be present in a different, undocumented form;
+  the new form is chosen for compatibility with GNU diff3's -L option.
+
+  rcsmerge and merge now have a -q option, just like their siblings do.
+
+  rcsclean's new -n option outputs what rcsclean would do,
+  without actually doing it.
+
+  RCS now attempts to ignore parts of an RCS file that look like they come
+  from a future version of RCS.
+
+  When properly configured, RCS now strictly conforms with Posix 1003.1-1990.
+  RCS can still be compiled in non-Posix traditional Unix environments,
+  and can use common BSD and USG extensions to Posix.
+  RCS is a conforming Standard C program, and also compiles under traditional C.
+
+  Arbitrary limits on internal table sizes have been removed.
+  The only limit now is the amount of memory available via malloc().
+
+  File temporaries, lock files, signals, and system call return codes
+  are now handled more cleanly, portably, and quickly.
+  Some race conditions have been removed.
+
+  A new compile-time option RCSPREFIX lets administrators avoid absolute path
+  names for subsidiary programs, trading speed for flexibility.
+
+  The configuration procedure is now more automatic.
+
+  Snooping has been removed.
+
+
+Version 4 was the first version distributed by FSF.
+Beside bug fixes, features new to RCS version 4 include:
+
+  The notion of default branch has been added; see rcs -b.
+
+
+Version 3 was included in the 4.3BSD distribution.
+
+
+Here are some possible future changes for RCS:
+
+  Bring back sccstorcs.
+
+  Add an option to `rcsmerge' so that it can use an arbitrary program
+  to do the 3-way merge, instead of the default `merge'.
+  Likewise for `rcsdiff' and `diff'.  It should be possible to pass
+  arbitrary options to these programs, and to the subsidiary `co's.
+
+  Add format options for finer control over the output of ident and rlog.
+  E.g. there should be an easy way for rlog to output lines like
+  `src/main.c 2.4 wft', one for each locked revision.
+  rlog options should have three orthogonal types: selecting files,
+  selecting revisions, and selecting rlog format.
+
+  Add format options for finer control over the output of keyword strings.
+  E.g. there should be some way to prepend @(#), and there should be some
+  way to change $ to some other character to disable further substitution.
+  These options should make the resulting files uneditable, like -kv.
+
+  Add long options, e.g. `--version'.  Unfortunately RCS's option syntax
+  is incompatible with getopt.  Perhaps the best way is to overload `rcs', e.g.
+  `rcs diff --keyword-substitution=old file' instead of `rcsdiff -ko file'.
+
+  Add a way to put only the interesting part of the path into the $Header
+  keyword expansion.
+
+  rlog -rM:N should work even if M and N have different numbers of fields,
+  so long as M is an ancestor of N or vice versa.
+
+  rcs should evaluate options in order; this allows rcs -oS -nS.
+
+  rcs should be able to fix minor mistakes in checkin dates and authors.
+
+  Be able to redo your most recent checkin with minor changes.
+
+  co -u shouldn't complain about a writable working file if it won't change
+  its contents.
+
+  Configure the Makefile automatically, as well as conf.h.
+
+  Add a new option to rcs that behaves like -o, but that doesn't lose the
+  nonempty log messages, but instead merges them with the next revision
+  if it exists, perhaps with a 1-line header containing author, date, etc.
+
+  Add a `-' option to take the list of pathnames from standard input.
+  Perhaps the pathnames should be null-terminated, not newline-terminated,
+  so that pathnames that contain newlines are handled properly.
+
+  Permit multiple option-pathname pairs, e.g. co -r1.4 a -r1.5 b.
+
+  Add options to allow arbitrary combinations of working file names
+  with RCS file names -- they shouldn't have to match.
+
+  Add an option to break a symbolic link to an RCS file,
+  instead of breaking the hard link that it points to.
+
+  Add ways to specify the earliest revision, the most recent revision,
+  the earliest or latest revision on a particular branch, and
+  the parent or child of some other revision.
+
+  If a user has multiple locks, perhaps ci should fall back on ci -k's
+  method to figure out which revision to use.
+
+  Symbolic names need not refer to existing branches and revisions.
+  rcs(1)'s BUGS section says this is a bug.  Is it?  If so, it should be fixed.
+
+  Add an option to rcs -o so that old log messages are not deleted if
+  the next undeleted revision exists, but are merely appended to the log
+  message of that revision.
+
+  ci -k should be able to get keyword values from the first `$Log' entry.
+
+  Add an option to rcsclean to clean directories recursively.
+
+  Write an rcsck program that repairs corrupted RCS files,
+  much as fsck repairs corrupted file systems.
+  For example, it should remove stale lock files.
+
+  Clean up the source code with a consistent indenting style.
+
+  Update the date parser to use the more modern getdate.y by Bellovin,
+  Salz, and Berets, or the even more modern getdate by Moraes.  None of
+  these getdate implementations are as robust as RCS's old warhorse in
+  avoiding problems like arithmetic overflow, so they'll have to be
+  fixed first.
+
+  Break up the code into a library so that it's easier to write new programs
+  that manipulate RCS files, and so that useless code is removed from the
+  existing programs.  For example, the rcs command contains unnecessary
+  keyword substitution baggage, and the merge command can be greatly pruned.
+
+  Make it easier to use your favorite text editor to edit log messages,
+  etc. instead of having to type them in irretrievably at the terminal.
+
+  Let the user specify a search path for default branches,
+  e.g. to use L as the default branch if it works, and M otherwise.
+  Let the user require that at least one entry in the default branch path works.
+  Let the user say that later entries in the default branch path are read only,
+  i.e. one cannot check in changes to them.
+  This should be an option settable by RCSINIT.
+
+  Add a way for a user to see which revisions affected which lines.
+
+  Have `rlog -nN F' print just the revision number that N translates to.
+  E.g. `rlog -nB. F' would print the highest revision on the branch B.
+  Use this to add an option -bB to rcsbranch, to freeze the named branch.
+  This should interact well with default branches.
+
+  Add a co option that prints the revision number before each line,
+  as SCCS's `get -m' does.
+
+The following projects require a change to RCS file format.
+
+  Allow keyword expansion to be changed on a per-revision basis,
+  not on a per-file basis as now.  This would allow -ko to be used
+  on imported revisions, with the default -kkv otherwise.
+
+  When two or more branches are merged, record all the ancestors
+  of the new revision.  The hard part of this is keeping track of all
+  the ancestors of a working file while it's checked out.
+
+  Add loose locking, which is like non-strict but applies to all users,
+  not just the owner of the RCS file.
+
+  Be able to store RCS files in compressed format.
+  Don't bother to use a .Z extension that would exceed file name length limits;
+  just look at the magic number.
+
+  Add locker commentary, e.g. `co -l -m"checkout to fix merge bug" foo'
+  to tell others why you checked out `foo'.
+  Also record the time when the revision was locked,
+  and perhaps the working pathname (if applicable).
+
+  Let the user mark an RCS revision as deleted; checking out such a revision
+  would result in no working file.  Similarly, using `co -d' with a date either
+  before the initial revision or after the file was marked deleted should
+  remove the working file.  For extra credit, extend the notion of `deleted' to
+  include `renamed'.  RCS should support arbitrary combinations of renaming and
+  deletion, e.g. renaming A to B and B to A, checking in new revisions to both
+  files, and then renaming them back.
+
+  Be able to check in an entire directory structure into a single RCS file.
+
+  Use a better scheme for locking revisions; the current scheme requires
+  changing the RCS file just to lock or unlock a revision.
+  The new scheme should coexist as well as possible with older versions of RCS,
+  and should avoid the rare NFS bugs mentioned in rcsedit.c.
+  E.g. if there's a reliable lockd running, RCS should use it
+  instead of relying on NFS.
+
+  Add rcs options for changing keyword names, e.g. XConsortium instead of Id.
+
+  Add a `$Description' keyword; but this may be tricky, since descriptions can
+  contain newlines and $s.
+
+  Add a `$Copyright' keyword that expands to a copyright notice.
+
+  Add frozen branches a la SCCS.  In general, be able to emulate all of
+  SCCS, so that an SCCS-to-RCS program can be practical.  For example,
+  there should be an equivalent to the SCCS prt command.
+
+  Add support for distributed RCS, where widely separated
+  users cannot easily access each others' RCS files,
+  and must periodically distribute and reconcile new revisions.
+
+  Be able to create empty branches.
+
+  Be able to store just deltas from a read-only principal copy,
+  e.g. from source on CD-ROM.
+
+  Improve RCS's method for storing binary files.
+  Although it is more efficient than SCCS's,
+  the diff algorithm is still line oriented,
+  and often generates long output for minor changes to an executable file.
+
+  From the user's point of view, it would be best if
+  RCS detected and handled binary files without human intervention,
+  switching expansion methods as needed from revision to revision.
+
+  Allow RCS to determine automagically whether -ko or -kb should be the default
+  by inspecting the file's contents or name.  The magic should be optional
+  and user-programmable.
+
+  Extend the grammar of RCS files so that keywords need not be in a fixed order.
+
+  Internationalize messages; unfortunately, there's no common standard yet.
+  This requires a change in RCS file format because of the
+  `empty log message' and `checked in with -k' hacks inside RCS files.
+
+  Add documentation in texinfo format.
diff --git a/gnu/usr.bin/rcs/REFS b/gnu/usr.bin/rcs/REFS
new file mode 100644
index 0000000000000..89fc823525ee9
--- /dev/null
+++ b/gnu/usr.bin/rcs/REFS
@@ -0,0 +1,90 @@
+Here are references to RCS and related free software and documentation.
+Some of this information changes often; see the Frequently Asked Questions
+for more up-to-date references.
+
+ $FreeBSD$
+
+
+Frequently Asked Questions (FAQs)
+
+<http://www.qucis.queensu.ca/Software-Engineering/>
+<ftp://rtfm.mit.edu//pub/usenet-by-hierarchy/comp/software-eng/>
+  for software engineering; e.g. see
+  <http://www.qucis.queensu.ca/Software-Engineering/blurb/rcs>.
+
+<http://www.iac.honeywell.com/Pub/Tech/CM/CMFAQ.html>
+<ftp://rtfm.mit.edu//pub/usenet-by-hierarchy/comp/software/config-mgmt/>
+  for configuration management
+
+<http://www.winternet.com/~zoo/cvs/FAQ.txt>
+<ftp://ftp.odi.com/pub/users/dgg/FAQ.gz>
+  for CVS (see below)
+
+
+RCS and related GNU project software
+
+<ftp://ftp.cs.purdue.edu/pub/RCS/>
+  The RCS project distribution directory also contains beta versions,
+  ports, and prebuilt documentation.
+
+<ftp://prep.ai.mit.edu/pub/gnu/>
+  The GNU project distribution directory contains:
+    diffutils-N-tar.gz
+      the latest diffutils release; recommended for RCS
+    emacs-N-tar.gz
+      The latest Emacs release contains VC, a version-control package
+      that makes RCS easier to use.
+    make-N-tar.gz
+      GNU Make, which can automatically build from RCS files.
+    rcs-N-tar.gz
+      the latest RCS release
+    cvs-N-tar.gz
+      the latest official CVS release (see below)
+
+<ftp://ftp.leo.org/pub/comp/os/os2/gnu/devtools/> DOS, OS/2 ports
+<ftp://ftp.cc.utexas.edu/microlib/nt/gnu/> NT port
+
+
+CVS
+
+CVS, the Concurrent Versions System, keeps tracks of source changes
+made by groups of developers working on the same files concurrently,
+allowing them to resync as needed.
+
+<http://www.winternet.com/~zoo/cvs/>
+<http://www.loria.fr/~molli/cvs-index.html>
+  These pages have useful information about CVS.
+
+<ftp://prep.ai.mit.edu/pub/gnu/cvs-1.3.tar.gz>
+  CVS 1.3 is the latest released version.
+
+<ftp://ftp.delos.com/pub/cvs/alpha/cvs-1.4A2.tar.gz>
+  CVS 1.4 is in alpha test, but it is recommended if you are installing CVS
+  for the first time, or on a recent operating system.
+
+<ftp://ftp-os2.cdrom.com/pub/os2/unix/> DOS, OS/2 ports
+<ftp://ftp.cc.utexas.edu/microlib/nt/gnu/> NT port
+
+<ftp://ftp.cyclic.com/pub/cvs/>
+  Cyclic CVS adds network transparency to CVS; it supports efficient,
+  reliable, and authenticated repository access via TCP/IP.
+
+
+Other software that uses RCS
+
+<ftp://ftp.nau.edu/pub/Aegis/>
+  Aegis manages revisions, baselines, mandatory reviews, and mandatory testing.
+
+<ftp://ftp.vix.com/pub/patches/csu/>
+  BCS, the Baseline Configuration System,
+  manages revisions, baselines, and staging areas.
+
+<ftp://riftp.osf.org/pub/ode/>
+  ODE, the Open Software Foundation Development Environment,
+  manages revisions, builds, and sandboxes.
+  OSF uses it for their own development.
+
+<ftp://bellcore.com/pub/Odin/>
+  Odin, a `make' replacement, can build directly from arbitrary revisions
+  without requiring checkouts of working copies.  It also handles
+  parallel builds on multiple remote hosts and of multiple variants.
diff --git a/gnu/usr.bin/rcs/ci/Makefile b/gnu/usr.bin/rcs/ci/Makefile
new file mode 100644
index 0000000000000..2fbb74f4238d1
--- /dev/null
+++ b/gnu/usr.bin/rcs/ci/Makefile
@@ -0,0 +1,8 @@
+PROG=	ci
+SRCS=	ci.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=	${LIBRCS}
+DPADD=	${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/ci/ci.1 b/gnu/usr.bin/rcs/ci/ci.1
new file mode 100644
index 0000000000000..1378af222cb8f
--- /dev/null
+++ b/gnu/usr.bin/rcs/ci/ci.1
@@ -0,0 +1,898 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds i \&\s-1ISO\s0
+.ds r \&\s-1RCS\s0
+.ds u \&\s-1UTC\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH CI 1 \*(Dt GNU
+.SH NAME
+ci \- check in RCS revisions
+.SH SYNOPSIS
+.B ci
+.RI [ options ] " file " .\|.\|.
+.SH DESCRIPTION
+.B ci
+stores new revisions into \*r files.
+Each pathname matching an \*r suffix
+is taken to be an \*r file.
+All others
+are assumed to be working files containing new revisions.
+.B ci
+deposits the contents of each working file
+into the corresponding \*r file.
+If only a working file is given,
+.B ci
+tries to find the corresponding \*r file in an \*r subdirectory
+and then in the working file's directory.
+For more details, see
+.SM "FILE NAMING"
+below.
+.PP
+For
+.B ci
+to work, the caller's login must be on the access list,
+except if the access list is empty or the caller is the superuser or the
+owner of the file.
+To append a new revision to an existing branch, the tip revision on
+that branch must be locked by the caller.  Otherwise, only a
+new branch can be created.  This restriction is not enforced
+for the owner of the file if non-strict locking is used
+(see
+.BR rcs (1)).
+A lock held by someone else can be broken with the
+.B rcs
+command.
+.PP
+Unless the
+.B \-f
+option is given,
+.B ci
+checks whether the revision to be deposited differs from the preceding one.
+If not, instead of creating a new revision
+.B ci
+reverts to the preceding one.
+To revert, ordinary
+.B ci
+removes the working file and any lock;
+.B "ci\ \-l"
+keeps and
+.B "ci\ \-u"
+removes any lock, and then they both generate a new working file much as if
+.B "co\ \-l"
+or
+.B "co\ \-u"
+had been applied to the preceding revision.
+When reverting, any
+.B \-n
+and
+.B \-s
+options apply to the preceding revision.
+.PP
+For each revision deposited,
+.B ci
+prompts for a log message.
+The log message should summarize the change and must be terminated by
+end-of-file or by a line containing
+.BR \&. "\ by"
+itself.
+If several files are checked in
+.B ci
+asks whether to reuse the
+previous log message.
+If the standard input is not a terminal,
+.B ci
+suppresses the prompt
+and uses the same log message for all files.
+See also
+.BR \-m .
+.PP
+If the \*r file does not exist,
+.B ci
+creates it and
+deposits the contents of the working file as the initial revision
+(default number:
+.BR 1.1 ).
+The access list is initialized to empty.
+Instead of the log message,
+.B ci
+requests descriptive text (see
+.B \-t
+below).
+.PP
+The number
+.I rev
+of the deposited revision can be given by any of the options
+.BR \-f ,
+.BR \-i ,
+.BR \-I ,
+.BR \-j ,
+.BR \-k ,
+.BR \-l ,
+.BR \-M ,
+.BR \-q ,
+.BR \-r ,
+or
+.BR \-u .
+.I rev
+can be symbolic, numeric, or mixed.
+Symbolic names in
+.I rev
+must already be defined;
+see the
+.B \-n
+and
+.B \-N
+options for assigning names during checkin.
+If
+.I rev
+is
+.BR $ ,
+.B ci
+determines the revision number from keyword values in the working file.
+.PP
+If
+.I rev
+begins with a period,
+then the default branch (normally the trunk) is prepended to it.
+If
+.I rev
+is a branch number followed by a period,
+then the latest revision on that branch is used.
+.PP
+If
+.I rev
+is a revision number, it must be higher than the latest
+one on the branch to which
+.I rev
+belongs, or must start a new branch.
+.PP
+If
+.I rev
+is a branch rather than a revision number,
+the new revision is appended to that branch.  The level number is obtained
+by incrementing the tip revision number of that branch.
+If
+.I rev
+indicates a non-existing branch,
+that branch is created with the initial revision numbered
+.IB rev .1\f1.\fP
+.br
+.ne 8
+.PP
+If
+.I rev
+is omitted,
+.B ci
+tries to derive the new revision number from
+the caller's last lock.  If the caller has locked the tip revision of a branch,
+the new revision is appended to that branch.
+The new revision number is obtained
+by incrementing the tip revision number.
+If the caller locked a non-tip revision, a new branch is started at
+that revision by incrementing the highest branch number at that revision.
+The default initial branch and level numbers are
+.BR 1 .
+.PP
+If
+.I rev
+is omitted and the caller has no lock, but owns
+the file and locking
+is not set to
+.IR strict ,
+then the revision is appended to the
+default branch (normally the trunk; see the
+.B \-b
+option of
+.BR rcs (1)).
+.PP
+Exception: On the trunk, revisions can be appended to the end, but
+not inserted.
+.SH OPTIONS
+.TP
+.BI \-r rev
+Check in revision
+.IR rev .
+.TP
+.BR \-r
+The bare
+.B \-r
+option (without any revision) has an unusual meaning in
+.BR ci .
+With other \*r commands, a bare
+.B \-r
+option specifies the most recent revision on the default branch,
+but with
+.BR ci ,
+a bare
+.B \-r
+option reestablishes the default behavior of releasing a lock and
+removing the working file, and is used to override any default
+.B \-l
+or
+.B \-u
+options established by shell aliases or scripts.
+.TP
+.BR \-l [\f2rev\fP]
+works like
+.BR \-r ,
+except it performs an additional
+.B "co\ \-l"
+for the
+deposited revision.  Thus, the deposited revision is immediately
+checked out again and locked.
+This is useful for saving a revision although one wants to continue
+editing it after the checkin.
+.TP
+.BR \-u [\f2rev\fP]
+works like
+.BR \-l ,
+except that the deposited revision is not locked.
+This lets one read the working file
+immediately after checkin.
+.RS
+.PP
+The
+.BR \-l ,
+bare
+.BR \-r ,
+and
+.B \-u
+options are mutually exclusive and silently override each other.
+For example,
+.B "ci\ \-u\ \-r"
+is equivalent to
+.B "ci\ \-r"
+because bare
+.B \-r
+overrides
+.BR \-u .
+.RE
+.TP
+.BR \-f [\f2rev\fP]
+forces a deposit; the new revision is deposited even it is not different
+from the preceding one.
+.TP
+.BR \-k [\f2rev\fP]
+searches the working file for keyword values to determine its revision number,
+creation date, state, and author (see
+.BR co (1)),
+and assigns these
+values to the deposited revision, rather than computing them locally.
+It also generates a default login message noting the login of the caller
+and the actual checkin date.
+This option is useful for software distribution.  A revision that is sent to
+several sites should be checked in with the
+.B \-k
+option at these sites to
+preserve the original number, date, author, and state.
+The extracted keyword values and the default log message can be overridden
+with the options
+.BR \-d ,
+.BR \-m ,
+.BR \-s ,
+.BR \-w ,
+and any option that carries a revision number.
+.TP
+.BR \-q [\f2rev\fP]
+quiet mode; diagnostic output is not printed.
+A revision that is not different from the preceding one is not deposited,
+unless
+.B \-f
+is given.
+.TP
+.BR \-i [\f2rev\fP]
+initial checkin; report an error if the \*r file already exists.
+This avoids race conditions in certain applications.
+.TP
+.BR \-j [\f2rev\fP]
+just checkin and do not initialize;
+report an error if the \*r file does not already exist.
+.TP
+.BR \-I [\f2rev\fP]
+interactive mode;
+the user is prompted and questioned
+even if the standard input is not a terminal.
+.TP
+.BR \-d "[\f2date\fP]"
+uses
+.I date
+for the checkin date and time.
+The
+.I date
+is specified in free format as explained in
+.BR co (1).
+This is useful for lying about the checkin date, and for
+.B \-k
+if no date is available.
+If
+.I date
+is empty, the working file's time of last modification is used.
+.TP
+.BR \-M [\f2rev\fP]
+Set the modification time on any new working file
+to be the date of the retrieved revision.
+For example,
+.BI "ci\ \-d\ \-M\ \-u" "\ f"
+does not alter
+.IR f 's
+modification time, even if
+.IR f 's
+contents change due to keyword substitution.
+Use this option with care; it can confuse
+.BR make (1).
+.TP
+.BI \-m "msg"
+uses the string
+.I msg
+as the log message for all revisions checked in.
+By convention, log messages that start with
+.B #
+are comments and are ignored by programs like GNU Emacs's
+.B vc
+package.
+Also, log messages that start with
+.BI { clumpname }
+(followed by white space) are meant to be clumped together if possible,
+even if they are associated with different files; the
+.BI { clumpname }
+label is used only for clumping,
+and is not considered to be part of the log message itself.
+.TP
+.BI \-n "name"
+assigns the symbolic name
+.I name
+to the number of the checked-in revision.
+.B ci
+prints an error message if
+.I name
+is already assigned to another
+number.
+.TP
+.BI \-N "name"
+same as
+.BR \-n ,
+except that it overrides a previous assignment of
+.IR name .
+.TP
+.BI \-s "state"
+sets the state of the checked-in revision to the identifier
+.IR state .
+The default state is
+.BR Exp .
+.TP
+.BI \-t file
+writes descriptive text from the contents of the named
+.I file
+into the \*r file,
+deleting the existing text.
+The
+.I file
+cannot begin with
+.BR \- .
+.TP
+.BI \-t\- string
+Write descriptive text from the
+.I string
+into the \*r file, deleting the existing text.
+.RS
+.PP
+The
+.B \-t
+option, in both its forms, has effect only during an initial checkin;
+it is silently ignored otherwise.
+.PP
+During the initial checkin, if
+.B \-t
+is not given,
+.B ci
+obtains the text from standard input,
+terminated by end-of-file or by a line containing
+.BR \&. "\ by"
+itself.
+The user is prompted for the text if interaction is possible; see
+.BR \-I .
+.PP
+For backward compatibility with older versions of \*r, a bare
+.B \-t
+option is ignored.
+.RE
+.TP
+.B \-T
+Set the \*r file's modification time to the new revision's time
+if the former precedes the latter and there is a new revision;
+preserve the \*r file's modification time otherwise.
+If you have locked a revision,
+.B ci
+usually updates the \*r file's modification time to the current time,
+because the lock is stored in the \*r file
+and removing the lock requires changing the \*r file.
+This can create an \*r file newer than the working file in one of two ways:
+first,
+.B "ci\ \-M"
+can create a working file with a date before the current time;
+second, when reverting to the previous revision
+the \*r file can change while the working file remains unchanged.
+These two cases can cause excessive recompilation caused by a
+.BR make (1)
+dependency of the working file on the \*r file.
+The
+.B \-T
+option inhibits this recompilation by lying about the \*r file's date.
+Use this option with care; it can suppress recompilation even when
+a checkin of one working file should affect
+another working file associated with the same \*r file.
+For example, suppose the \*r file's time is 01:00,
+the (changed) working file's time is 02:00,
+some other copy of the working file has a time of 03:00,
+and the current time is 04:00.
+Then
+.B "ci\ \-d\ \-T"
+sets the \*r file's time to 02:00 instead of the usual 04:00;
+this causes
+.BR make (1)
+to think (incorrectly) that the other copy is newer than the \*r file.
+.TP
+.BI \-w "login"
+uses
+.I login
+for the author field of the deposited revision.
+Useful for lying about the author, and for
+.B \-k
+if no author is available.
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.IR n .
+See
+.BR co (1)
+for details.
+.TP
+.BI \-x "suffixes"
+specifies the suffixes for \*r files.
+A nonempty suffix matches any pathname ending in the suffix.
+An empty suffix matches any pathname of the form
+.BI RCS/ path
+or
+.IB path1 /RCS/ path2.
+The
+.B \-x
+option can specify a list of suffixes
+separated by
+.BR / .
+For example,
+.B \-x,v/
+specifies two suffixes:
+.B ,v
+and the empty suffix.
+If two or more suffixes are specified,
+they are tried in order when looking for an \*r file;
+the first one that works is used for that file.
+If no \*r file is found but an \*r file can be created,
+the suffixes are tried in order
+to determine the new \*r file's name.
+The default for
+.IR suffixes
+is installation-dependent; normally it is
+.B ,v/
+for hosts like Unix that permit commas in filenames,
+and is empty (i.e. just the empty suffix) for other hosts.
+.TP
+.BI \-z zone
+specifies the date output format in keyword substitution,
+and specifies the default time zone for
+.I date
+in the
+.BI \-d date
+option.
+The
+.I zone
+should be empty, a numeric \*u offset, or the special string
+.B LT
+for local time.
+The default is an empty
+.IR zone ,
+which uses the traditional \*r format of \*u without any time zone indication
+and with slashes separating the parts of the date;
+otherwise, times are output in \*i 8601 format with time zone indication.
+For example, if local time is January 11, 1990, 8pm Pacific Standard Time,
+eight hours west of \*u,
+then the time is output as follows:
+.RS
+.LP
+.RS
+.nf
+.ta \w'\f3\-z+05:30\fP  'u +\w'\f31990-01-11 09:30:00+05:30\fP  'u
+.ne 4
+\f2option\fP	\f2time output\fP
+\f3\-z\fP	\f31990/01/12 04:00:00\fP	\f2(default)\fP
+\f3\-zLT\fP	\f31990-01-11 20:00:00\-08\fP
+\f3\-z+05:30\fP	\f31990-01-12 09:30:00+05:30\fP
+.ta 4n +4n +4n +4n
+.fi
+.RE
+.LP
+The
+.B \-z
+option does not affect dates stored in \*r files,
+which are always \*u.
+.SH "FILE NAMING"
+Pairs of \*r files and working files can be specified in three ways
+(see also the
+example section).
+.PP
+1) Both the \*r file and the working file are given.  The \*r pathname is of
+the form
+.IB path1 / workfileX
+and the working pathname is of the form
+.IB path2 / workfile
+where
+.IB path1 /
+and
+.IB path2 /
+are (possibly different or empty) paths,
+.I workfile
+is a filename, and
+.I X
+is an \*r suffix.
+If
+.I X
+is empty,
+.IB path1 /
+must start with
+.B RCS/
+or must contain
+.BR /RCS/ .
+.PP
+2) Only the \*r file is given.  Then the working file is created in the current
+directory and its name is derived from the name of the \*r file
+by removing
+.IB path1 /
+and the suffix
+.IR X .
+.PP
+3) Only the working file is given.
+Then
+.B ci
+considers each \*r suffix
+.I X
+in turn, looking for an \*r file of the form
+.IB path2 /RCS/ workfileX
+or (if the former is not found and
+.I X
+is nonempty)
+.IB path2 / workfileX.
+.PP
+If the \*r file is specified without a path in 1) and 2),
+.B ci
+looks for the \*r file first in the directory
+.B ./RCS
+and then in the current
+directory.
+.PP
+.B ci
+reports an error if an attempt to open an \*r file fails for an unusual reason,
+even if the \*r file's pathname is just one of several possibilities.
+For example, to suppress use of \*r commands in a directory
+.IR d ,
+create a regular file named
+.IB d /RCS
+so that casual attempts to use \*r commands in
+.I d
+fail because
+.IB d /RCS
+is not a directory.
+.SH EXAMPLES
+Suppose
+.B ,v
+is an \*r suffix and the current directory contains a subdirectory
+.B RCS
+with an \*r file
+.BR io.c,v .
+Then each of the following commands check in a copy of
+.B io.c
+into
+.B RCS/io.c,v
+as the latest revision, removing
+.BR io.c .
+.LP
+.RS
+.nf
+.ft 3
+ci  io.c;    ci  RCS/io.c,v;   ci  io.c,v;
+ci  io.c  RCS/io.c,v;    ci  io.c  io.c,v;
+ci  RCS/io.c,v  io.c;    ci  io.c,v  io.c;
+.ft
+.fi
+.RE
+.PP
+Suppose instead that the empty suffix
+is an \*r suffix and the current directory contains a subdirectory
+.B RCS
+with an \*r file
+.BR io.c .
+The each of the following commands checks in a new revision.
+.LP
+.RS
+.nf
+.ft 3
+ci  io.c;    ci  RCS/io.c;
+ci  io.c  RCS/io.c;
+ci  RCS/io.c  io.c;
+.ft
+.fi
+.RE
+.SH "FILE MODES"
+An \*r file created by
+.B ci
+inherits the read and execute permissions
+from the working file.  If the \*r file exists already,
+.B ci
+preserves its read and execute permissions.
+.B ci
+always turns off all write permissions of \*r files.
+.SH FILES
+Temporary files are created in the directory containing
+the working file, and also in the temporary directory (see
+.B \s-1TMPDIR\s0
+under
+.BR \s-1ENVIRONMENT\s0 ).
+A semaphore file or files are created in the directory containing the \*r file.
+With a nonempty suffix, the semaphore names begin with
+the first character of the suffix; therefore, do not specify an suffix
+whose first character could be that of a working filename.
+With an empty suffix, the semaphore names end with
+.B _
+so working filenames should not end in
+.BR _ .
+.PP
+.B ci
+never changes an \*r or working file.
+Normally,
+.B ci
+unlinks the file and creates a new one;
+but instead of breaking a chain of one or more symbolic links to an \*r file,
+it unlinks the destination file instead.
+Therefore,
+.B ci
+breaks any hard or symbolic links to any working file it changes;
+and hard links to \*r files are ineffective,
+but symbolic links to \*r files are preserved.
+.PP
+The effective user must be able to
+search and write the directory containing the \*r file.
+Normally, the real user must be able to
+read the \*r and working files
+and to search and write the directory containing the working file;
+however, some older hosts
+cannot easily switch between real and effective users,
+so on these hosts the effective user is used for all accesses.
+The effective user is the same as the real user
+unless your copies of
+.B ci
+and
+.B co
+have setuid privileges.
+As described in the next section,
+these privileges yield extra security if
+the effective user owns all \*r files and directories,
+and if only the effective user can write \*r directories.
+.PP
+Users can control access to \*r files by setting the permissions
+of the directory containing the files; only users with write access
+to the directory can use \*r commands to change its \*r files.
+For example, in hosts that allow a user to belong to several groups,
+one can make a group's \*r directories writable to that group only.
+This approach suffices for informal projects,
+but it means that any group member can arbitrarily change the group's \*r files,
+and can even remove them entirely.
+Hence more formal projects sometimes distinguish between an \*r administrator,
+who can change the \*r files at will, and other project members,
+who can check in new revisions but cannot otherwise change the \*r files.
+.SH "SETUID USE"
+To prevent anybody but their \*r administrator from deleting revisions,
+a set of users can employ setuid privileges as follows.
+.nr n \w'\(bu'+2n-1/1n
+.ds n \nn
+.if \n(.g .if r an-tag-sep .ds n \w'\(bu'u+\n[an-tag-sep]u
+.IP \(bu \*n
+Check that the host supports \*r setuid use.
+Consult a trustworthy expert if there are any doubts.
+It is best if the
+.B seteuid
+system call works as described in Posix 1003.1a Draft 5,
+because \*r can switch back and forth easily
+between real and effective users, even if the real user is
+.BR root .
+If not, the second best is if the
+.B setuid
+system call supports saved setuid
+(the {\s-1_POSIX_SAVED_IDS\s0} behavior of Posix 1003.1-1990);
+this fails only if the real or effective user is
+.BR root .
+If \*r detects any failure in setuid, it quits immediately.
+.IP \(bu \nn
+Choose a user
+.I A
+to serve as \*r administrator for the set of users.
+Only
+.I A
+can invoke the
+.B rcs
+command on the users' \*r files.
+.I A
+should not be
+.B root
+or any other user with special powers.
+Mutually suspicious sets of users should use different administrators.
+.IP \(bu \nn
+Choose a pathname
+.I B
+to be a directory of files to be executed by the users.
+.IP \(bu \nn
+Have
+.I A
+set up
+.I B
+to contain copies of
+.B ci
+and
+.B co
+that are setuid to
+.I A
+by copying the commands from their standard installation directory
+.I D
+as follows:
+.LP
+.RS
+.nf
+.ne 3
+\f3mkdir\fP  \f2B\fP
+\f3cp\fP  \f2D\fP\^\f3/c[io]\fP  \f2B\fP
+\f3chmod  go\-w,u+s\fP  \f2B\fP\f3/c[io]\fP
+.fi
+.RE
+.IP \(bu \nn
+Have each user prepend
+.I B
+to their path as follows:
+.LP
+.RS
+.nf
+.ne 2
+\f3PATH=\fP\f2B\fP\f3:$PATH;  export  PATH\fP  # ordinary shell
+\f3set  path=(\fP\f2B\fP  \f3$path)\fP  # C shell
+.fi
+.RE
+.IP \(bu \nn
+Have
+.I A
+create each \*r directory
+.I R
+with write access only to
+.I A
+as follows:
+.LP
+.RS
+.nf
+.ne 2
+\f3mkdir\fP  \f2R\fP
+\f3chmod  go\-w\fP  \f2R\fP
+.fi
+.RE
+.IP \(bu \nn
+If you want to let only certain users read the \*r files,
+put the users into a group
+.IR G ,
+and have
+.I A
+further protect the \*r directory as follows:
+.LP
+.RS
+.nf
+.ne 2
+\f3chgrp\fP  \f2G  R\fP
+\f3chmod  g\-w,o\-rwx\fP  \f2R\fP
+.fi
+.RE
+.IP \(bu \nn
+Have
+.I A
+copy old \*r files (if any) into
+.IR R ,
+to ensure that
+.I A
+owns them.
+.IP \(bu \nn
+An \*r file's access list limits who can check in and lock revisions.
+The default access list is empty,
+which grants checkin access to anyone who can read the \*r file.
+If you want limit checkin access,
+have
+.I A
+invoke
+.B "rcs\ \-a"
+on the file; see
+.BR rcs (1).
+In particular,
+.BI "rcs\ \-e\ \-a" A
+limits access to just
+.IR A .
+.IP \(bu \nn
+Have
+.I A
+initialize any new \*r files with
+.B "rcs\ \-i"
+before initial checkin, adding the
+.B \-a
+option if you want to limit checkin access.
+.IP \(bu \nn
+Give setuid privileges only to
+.BR ci ,
+.BR co ,
+and
+.BR rcsclean ;
+do not give them to
+.B rcs
+or to any other command.
+.IP \(bu \nn
+Do not use other setuid commands to invoke \*r commands;
+setuid is trickier than you think!
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+A backslash escapes spaces within an option.
+The
+.B \s-1RCSINIT\s0
+options are prepended to the argument lists of most \*r commands.
+Useful
+.B \s-1RCSINIT\s0
+options include
+.BR \-q ,
+.BR \-V ,
+.BR \-x ,
+and
+.BR \-z .
+.TP
+.B \s-1TMPDIR\s0
+Name of the temporary directory.
+If not set, the environment variables
+.B \s-1TMP\s0
+and
+.B \s-1TEMP\s0
+are inspected instead and the first value found is taken;
+if none of them are set,
+a host-dependent default is used, typically
+.BR /tmp .
+.SH DIAGNOSTICS
+For each revision,
+.B ci
+prints the \*r file, the working file, and the number
+of both the deposited and the preceding revision.
+The exit status is zero if and only if all operations were successful.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH "SEE ALSO"
+co(1),
+ident(1), make(1), rcs(1), rcsclean(1), rcsdiff(1),
+rcsintro(1), rcsmerge(1), rlog(1), setuid(2), rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.br
diff --git a/gnu/usr.bin/rcs/ci/ci.c b/gnu/usr.bin/rcs/ci/ci.c
new file mode 100644
index 0000000000000..749a4cf6dbe93
--- /dev/null
+++ b/gnu/usr.bin/rcs/ci/ci.c
@@ -0,0 +1,1318 @@
+/* Check in revisions of RCS files from working files.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.30  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.29  1995/06/01 16:23:43  eggert
+ * (main): Add -kb.
+ * Use `cmpdate', not `cmpnum', to compare dates.
+ * This is for MKS RCS's incompatible 20th-century date format.
+ * Don't worry about errno after ftruncate fails.
+ * Fix input file rewinding bug when large_memory && !maps_memory
+ * and checking in a branch tip.
+ *
+ * (fixwork): Fall back on chmod if fchmod fails, since it might be ENOSYS.
+ *
+ * Revision 5.28  1994/03/20 04:52:58  eggert
+ * Do not generate a corrupted RCS file if the user modifies the working file
+ * while `ci' is running.
+ * Do not remove the lock when `ci -l' reverts.
+ * Move buffer-flushes out of critical sections, since they aren't critical.
+ * Use ORCSerror to clean up after a fatal error.
+ * Specify subprocess input via file descriptor, not file name.
+ *
+ * Revision 5.27  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.  Don't print usage twice.
+ *
+ * Revision 5.26  1993/11/03 17:42:27  eggert
+ * Add -z.  Don't subtract from RCS file timestamp even if -T.
+ * Scan for and use Name keyword if -k.
+ * Don't discard ignored phrases.  Improve quality of diagnostics.
+ *
+ * Revision 5.25  1992/07/28  16:12:44  eggert
+ * Add -i, -j, -V.  Check that working and RCS files are distinct.
+ *
+ * Revision 5.24  1992/02/17  23:02:06  eggert
+ * `-rREV' now just specifies a revision REV; only bare `-r' reverts to default.
+ * Add -T.
+ *
+ * Revision 5.23  1992/01/27  16:42:51  eggert
+ * Always unlock branchpoint if caller has a lock.
+ * Add support for bad_chmod_close, bad_creat0.  lint -> RCS_lint
+ *
+ * Revision 5.22  1992/01/06  02:42:34  eggert
+ * Invoke utime() before chmod() to keep some buggy systems happy.
+ *
+ * Revision 5.21  1991/11/20  17:58:07  eggert
+ * Don't read the delta tree from a nonexistent RCS file.
+ *
+ * Revision 5.20  1991/10/07  17:32:46  eggert
+ * Fix log bugs.  Remove lint.
+ *
+ * Revision 5.19  1991/09/26  23:10:30  eggert
+ * Plug file descriptor leak.
+ *
+ * Revision 5.18  1991/09/18  07:29:10  eggert
+ * Work around a common ftruncate() bug.
+ *
+ * Revision 5.17  1991/09/10  22:15:46  eggert
+ * Fix test for redirected stdin.
+ *
+ * Revision 5.16  1991/08/19  23:17:54  eggert
+ * When there are no changes, revert to previous revision instead of aborting.
+ * Add piece tables, -M, -r$.  Tune.
+ *
+ * Revision 5.15  1991/04/21  11:58:14  eggert
+ * Ensure that working file is newer than RCS file after ci -[lu].
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.14  1991/02/28  19:18:47  eggert
+ * Don't let a setuid ci create a new RCS file; rcs -i -a must be run first.
+ * Fix ci -ko -l mode bug.  Open work file at most once.
+ *
+ * Revision 5.13  1991/02/25  07:12:33  eggert
+ * getdate -> getcurdate (SVR4 name clash)
+ *
+ * Revision 5.12  1990/12/31  01:00:12  eggert
+ * Don't use uninitialized storage when handling -{N,n}.
+ *
+ * Revision 5.11  1990/12/04  05:18:36  eggert
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.10  1990/11/05  20:30:10  eggert
+ * Don't remove working file when aborting due to no changes.
+ *
+ * Revision 5.9  1990/11/01  05:03:23  eggert
+ * Add -I and new -t behavior.  Permit arbitrary data in logs.
+ *
+ * Revision 5.8  1990/10/04  06:30:09  eggert
+ * Accumulate exit status across files.
+ *
+ * Revision 5.7  1990/09/25  20:11:46  hammer
+ * fixed another small typo
+ *
+ * Revision 5.6  1990/09/24  21:48:50  hammer
+ * added cleanups from Paul Eggert.
+ *
+ * Revision 5.5  1990/09/21  06:16:38  hammer
+ * made it handle multiple -{N,n}'s.  Also, made it treat re-directed stdin
+ * the same as the terminal
+ *
+ * Revision 5.4  1990/09/20  02:38:51  eggert
+ * ci -k now checks dates more thoroughly.
+ *
+ * Revision 5.3  1990/09/11  02:41:07  eggert
+ * Fix revision bug with `ci -k file1 file2'.
+ *
+ * Revision 5.2  1990/09/04  08:02:10  eggert
+ * Permit adjacent revisions with identical time stamps (possible on fast hosts).
+ * Improve incomplete line handling.  Standardize yes-or-no procedure.
+ *
+ * Revision 5.1  1990/08/29  07:13:44  eggert
+ * Expand locker value like co.  Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:10:00  eggert
+ * Don't require a final newline.
+ * Make lock and temp files faster and safer.
+ * Remove compile-time limits; use malloc instead.
+ * Permit dates past 1999/12/31.  Switch to GMT.
+ * Add setuid support.  Don't pass +args to diff.  Check diff's output.
+ * Ansify and Posixate.  Add -k, -V.  Remove snooping.  Tune.
+ * Check diff's output.
+ *
+ * Revision 4.9  89/05/01  15:10:54  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.8  88/11/08  13:38:23  narten
+ * changes from root@seismo.CSS.GOV (Super User)
+ * -d with no arguments uses the mod time of the file it is checking in
+ *
+ * Revision 4.7  88/08/09  19:12:07  eggert
+ * Make sure workfile is a regular file; use its mode if RCSfile doesn't have one.
+ * Use execv(), not system(); allow cc -R; remove lint.
+ * isatty(fileno(stdin)) -> ttystdin()
+ *
+ * Revision 4.6  87/12/18  11:34:41  narten
+ * lint cleanups (from Guy Harris)
+ *
+ * Revision 4.5  87/10/18  10:18:48  narten
+ * Updating version numbers. Changes relative to revision 1.1 are actually
+ * relative to 4.3
+ *
+ * Revision 1.3  87/09/24  13:57:19  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:21:33  jenkins
+ * Port to suns
+ *
+ * Revision 4.3  83/12/15  12:28:54  wft
+ * ci -u and ci -l now set mode of working file properly.
+ *
+ * Revision 4.2  83/12/05  13:40:54  wft
+ * Merged with 3.9.1.1: added calls to clearerr(stdin).
+ * made rewriteflag external.
+ *
+ * Revision 4.1  83/05/10  17:03:06  wft
+ * Added option -d and -w, and updated assingment of date, etc. to new delta.
+ * Added handling of default branches.
+ * Option -k generates std. log message; fixed undef. pointer in reading of log.
+ * Replaced getlock() with findlock(), link--unlink with rename(),
+ * getpwuid() with getcaller().
+ * Moved all revision number generation to new routine addelta().
+ * Removed calls to stat(); now done by pairfilenames().
+ * Changed most calls to catchints() with restoreints().
+ * Directed all interactive messages to stderr.
+ *
+ * Revision 3.9.1.1  83/10/19  04:21:03  lepreau
+ * Added clearerr(stdin) to getlogmsg() for re-reading stdin.
+ *
+ * Revision 3.9  83/02/15  15:25:44  wft
+ * 4.2 prerelease
+ *
+ * Revision 3.9  83/02/15  15:25:44  wft
+ * Added call to fastcopy() to copy remainder of RCS file.
+ *
+ * Revision 3.8  83/01/14  15:34:05  wft
+ * Added ignoring of interrupts while new RCS file is renamed;
+ * Avoids deletion of RCS files by interrupts.
+ *
+ * Revision 3.7  82/12/10  16:09:20  wft
+ * Corrected checking of return code from diff.
+ *
+ * Revision 3.6  82/12/08  21:34:49  wft
+ * Using DATEFORM to prepare date of checked-in revision;
+ * Fixed return from addbranch().
+ *
+ * Revision 3.5  82/12/04  18:32:42  wft
+ * Replaced getdelta() with gettree(), SNOOPDIR with SNOOPFILE. Updated
+ * field lockedby in removelock(), moved getlogmsg() before calling diff.
+ *
+ * Revision 3.4  82/12/02  13:27:13  wft
+ * added option -k.
+ *
+ * Revision 3.3  82/11/28  20:53:31  wft
+ * Added mustcheckin() to check for redundant checkins.
+ * Added xpandfile() to do keyword expansion for -u and -l;
+ * -m appends linefeed to log message if necessary.
+ * getlogmsg() suppresses prompt if stdin is not a terminal.
+ * Replaced keeplock with lockflag, fclose() with ffclose(),
+ * %02d with %.2d, getlogin() with getpwuid().
+ *
+ * Revision 3.2  82/10/18  20:57:23  wft
+ * An RCS file inherits its mode during the first ci from the working file,
+ * otherwise it stays the same, except that write permission is removed.
+ * Fixed ci -l, added ci -u (both do an implicit co after the ci).
+ * Fixed call to getlogin(), added call to getfullRCSname(), added check
+ * for write error.
+ * Changed conflicting identifiers.
+ *
+ * Revision 3.1  82/10/13  16:04:59  wft
+ * fixed type of variables receiving from getc() (char -> int).
+ * added include file dbm.h for getting BYTESIZ. This is used
+ * to check the return code from diff portably.
+ */
+
+#include "rcsbase.h"
+
+struct Symrev {
+       char const *ssymbol;
+       int override;
+       struct Symrev * nextsym;
+};
+
+static char const *getcurdate P((void));
+static int addbranch P((struct hshentry*,struct buf*,int));
+static int addelta P((void));
+static int addsyms P((char const*));
+static int fixwork P((mode_t,time_t));
+static int removelock P((struct hshentry*));
+static int xpandfile P((RILE*,struct hshentry const*,char const**,int));
+static struct cbuf getlogmsg P((void));
+static void cleanup P((void));
+static void incnum P((char const*,struct buf*));
+static void addassoclst P((int,char const*));
+
+static FILE *exfile;
+static RILE *workptr;			/* working file pointer		*/
+static struct buf newdelnum;		/* new revision number		*/
+static struct cbuf msg;
+static int exitstatus;
+static int forceciflag;			/* forces check in		*/
+static int keepflag, keepworkingfile, rcsinitflag;
+static struct hshentries *gendeltas;	/* deltas to be generated	*/
+static struct hshentry *targetdelta;	/* old delta to be generated	*/
+static struct hshentry newdelta;	/* new delta to be inserted	*/
+static struct stat workstat;
+static struct Symrev *assoclst, **nextassoc;
+
+mainProg(ciId, "ci", "$FreeBSD$")
+{
+	static char const cmdusage[] =
+		"\nci usage: ci -{fIklMqru}[rev] -d[date] -mmsg -{nN}name -sstate -ttext -T -Vn -wwho -xsuff -zzone file ...";
+	static char const default_state[] = DEFAULTSTATE;
+
+	char altdate[datesize];
+	char olddate[datesize];
+	char newdatebuf[datesize + zonelenmax];
+	char targetdatebuf[datesize + zonelenmax];
+	char *a, **newargv, *textfile;
+	char const *author, *krev, *rev, *state;
+	char const *diffname, *expname;
+	char const *newworkname;
+	int initflag, mustread;
+	int lockflag, lockthis, mtimeflag, removedlock, Ttimeflag;
+	int r;
+	int changedRCS, changework, dolog, newhead;
+	int usestatdate; /* Use mod time of file for -d.  */
+	mode_t newworkmode; /* mode for working file */
+	time_t mtime, wtime;
+	struct hshentry *workdelta;
+
+	setrid();
+
+	author = rev = state = textfile = 0;
+	initflag = lockflag = mustread = false;
+	mtimeflag = false;
+	Ttimeflag = false;
+	altdate[0]= '\0'; /* empty alternate date for -d */
+	usestatdate=false;
+	suffixes = X_DEFAULT;
+	nextassoc = &assoclst;
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	while (a = *++argv,  0<--argc && *a++=='-') {
+		switch (*a++) {
+
+                case 'r':
+			if (*a)
+				goto revno;
+			keepworkingfile = lockflag = false;
+			break;
+
+		case 'l':
+			keepworkingfile = lockflag = true;
+		revno:
+			if (*a) {
+				if (rev) warn("redefinition of revision number");
+				rev = a;
+                        }
+                        break;
+
+                case 'u':
+                        keepworkingfile=true; lockflag=false;
+                        goto revno;
+
+		case 'i':
+			initflag = true;
+			goto revno;
+
+		case 'j':
+			mustread = true;
+			goto revno;
+
+		case 'I':
+			interactiveflag = true;
+			goto revno;
+
+                case 'q':
+                        quietflag=true;
+                        goto revno;
+
+                case 'f':
+                        forceciflag=true;
+                        goto revno;
+
+                case 'k':
+                        keepflag=true;
+                        goto revno;
+
+                case 'm':
+			if (msg.size) redefined('m');
+			msg = cleanlogmsg(a, strlen(a));
+			if (!msg.size)
+				error("missing message for -m option");
+                        break;
+
+                case 'n':
+			if (!*a) {
+                                error("missing symbolic name after -n");
+				break;
+            		}
+			checkssym(a);
+			addassoclst(false, a);
+		        break;
+
+		case 'N':
+			if (!*a) {
+                                error("missing symbolic name after -N");
+				break;
+            		}
+			checkssym(a);
+			addassoclst(true, a);
+		        break;
+
+                case 's':
+			if (*a) {
+				if (state) redefined('s');
+				checksid(a);
+				state = a;
+			} else
+				error("missing state for -s option");
+                        break;
+
+                case 't':
+			if (*a) {
+				if (textfile) redefined('t');
+				textfile = a;
+                        }
+                        break;
+
+		case 'd':
+			if (altdate[0] || usestatdate)
+				redefined('d');
+			altdate[0] = '\0';
+			if (!(usestatdate = !*a))
+				str2date(a, altdate);
+                        break;
+
+		case 'M':
+			mtimeflag = true;
+			goto revno;
+
+		case 'w':
+			if (*a) {
+				if (author) redefined('w');
+				checksid(a);
+				author = a;
+			} else
+				error("missing author for -w option");
+                        break;
+
+		case 'x':
+			suffixes = a;
+			break;
+
+		case 'V':
+			setRCSversion(*argv);
+			break;
+
+		case 'z':
+			zone_set(a);
+			break;
+
+		case 'T':
+			if (!*a) {
+				Ttimeflag = true;
+				break;
+			}
+			/* fall into */
+                default:
+			error("unknown option: %s%s", *argv, cmdusage);
+                };
+        }  /* end processing of options */
+
+	/* Handle all pathnames.  */
+	if (nerror) cleanup();
+	else if (argc < 1) faterror("no input file%s", cmdusage);
+	else for (;  0 < argc;  cleanup(), ++argv, --argc) {
+	targetdelta = 0;
+	ffree();
+
+	switch (pairnames(argc, argv, rcswriteopen, mustread, false)) {
+
+        case -1:                /* New RCS file */
+#		if has_setuid && has_getuid
+		    if (euid() != ruid()) {
+			workerror("setuid initial checkin prohibited; use `rcs -i -a' first");
+			continue;
+		    }
+#		endif
+		rcsinitflag = true;
+                break;
+
+        case 0:                 /* Error */
+                continue;
+
+        case 1:                 /* Normal checkin with prev . RCS file */
+		if (initflag) {
+			rcserror("already exists");
+			continue;
+		}
+		rcsinitflag = !Head;
+        }
+
+	/*
+	 * RCSname contains the name of the RCS file, and
+	 * workname contains the name of the working file.
+	 * If the RCS file exists, finptr contains the file descriptor for the
+	 * RCS file, and RCSstat is set. The admin node is initialized.
+         */
+
+	diagnose("%s  <--  %s\n", RCSname, workname);
+
+	if (!(workptr = Iopen(workname, FOPEN_R_WORK, &workstat))) {
+		eerror(workname);
+		continue;
+	}
+
+	if (finptr) {
+		if (same_file(RCSstat, workstat, 0)) {
+			rcserror("RCS file is the same as working file %s.",
+				workname
+			);
+			continue;
+		}
+		if (!checkaccesslist())
+			continue;
+	}
+
+	krev = rev;
+        if (keepflag) {
+                /* get keyword values from working file */
+		if (!getoldkeys(workptr)) continue;
+		if (!rev  &&  !*(krev = prevrev.string)) {
+			workerror("can't find a revision number");
+                        continue;
+                }
+		if (!*prevdate.string && *altdate=='\0' && usestatdate==false)
+			workwarn("can't find a date");
+		if (!*prevauthor.string && !author)
+			workwarn("can't find an author");
+		if (!*prevstate.string && !state)
+			workwarn("can't find a state");
+        } /* end processing keepflag */
+
+	/* Read the delta tree.  */
+	if (finptr)
+	    gettree();
+
+        /* expand symbolic revision number */
+	if (!fexpandsym(krev, &newdelnum, workptr))
+	    continue;
+
+        /* splice new delta into tree */
+	if ((removedlock = addelta()) < 0)
+	    continue;
+
+	newdelta.num = newdelnum.string;
+	newdelta.branches = 0;
+	newdelta.lockedby = 0; /* This might be changed by addlock().  */
+	newdelta.selector = true;
+	newdelta.name = 0;
+	clear_buf(&newdelta.ig);
+	clear_buf(&newdelta.igtext);
+	/* set author */
+	if (author)
+		newdelta.author=author;     /* set author given by -w         */
+	else if (keepflag && *prevauthor.string)
+		newdelta.author=prevauthor.string; /* preserve old author if possible*/
+	else    newdelta.author=getcaller();/* otherwise use caller's id      */
+	newdelta.state = default_state;
+	if (state)
+		newdelta.state=state;       /* set state given by -s          */
+	else if (keepflag && *prevstate.string)
+		newdelta.state=prevstate.string;   /* preserve old state if possible */
+	if (usestatdate) {
+	    time2date(workstat.st_mtime, altdate);
+	}
+	if (*altdate!='\0')
+		newdelta.date=altdate;      /* set date given by -d           */
+	else if (keepflag && *prevdate.string) {
+		/* Preserve old date if possible.  */
+		str2date(prevdate.string, olddate);
+		newdelta.date = olddate;
+	} else
+		newdelta.date = getcurdate();  /* use current date */
+	/* now check validity of date -- needed because of -d and -k          */
+	if (targetdelta &&
+	    cmpdate(newdelta.date,targetdelta->date) < 0) {
+		rcserror("Date %s precedes %s in revision %s.",
+			date2str(newdelta.date, newdatebuf),
+			date2str(targetdelta->date, targetdatebuf),
+			targetdelta->num
+		);
+		continue;
+	}
+
+
+	if (lockflag  &&  addlock(&newdelta, true) < 0) continue;
+
+	if (keepflag && *prevname.string)
+	    if (addsymbol(newdelta.num, prevname.string, false)  <  0)
+		continue;
+	if (!addsyms(newdelta.num))
+	    continue;
+
+
+	putadmin();
+        puttree(Head,frewrite);
+	putdesc(false,textfile);
+
+	changework = Expand < MIN_UNCHANGED_EXPAND;
+	dolog = true;
+	lockthis = lockflag;
+	workdelta = &newdelta;
+
+        /* build rest of file */
+	if (rcsinitflag) {
+		diagnose("initial revision: %s\n", newdelta.num);
+                /* get logmessage */
+                newdelta.log=getlogmsg();
+		putdftext(&newdelta, workptr, frewrite, false);
+		RCSstat.st_mode = workstat.st_mode;
+		RCSstat.st_nlink = 0;
+		changedRCS = true;
+        } else {
+		diffname = maketemp(0);
+		newhead  =  Head == &newdelta;
+		if (!newhead)
+			foutptr = frewrite;
+		expname = buildrevision(
+			gendeltas, targetdelta, (FILE*)0, false
+		);
+		if (
+		    !forceciflag  &&
+		    strcmp(newdelta.state, targetdelta->state) == 0  &&
+		    (changework = rcsfcmp(
+			workptr, &workstat, expname, targetdelta
+		    )) <= 0
+		) {
+		    diagnose("file is unchanged; reverting to previous revision %s\n",
+			targetdelta->num
+		    );
+		    if (removedlock < lockflag) {
+			diagnose("previous revision was not locked; ignoring -l option\n");
+			lockthis = 0;
+		    }
+		    dolog = false;
+		    if (! (changedRCS = lockflag<removedlock || assoclst))
+			workdelta = targetdelta;
+		    else {
+			/*
+			 * We have started to build the wrong new RCS file.
+			 * Start over from the beginning.
+			 */
+			long hwm = ftell(frewrite);
+			int bad_truncate;
+			Orewind(frewrite);
+
+			/*
+			* Work around a common ftruncate() bug:
+			* NFS won't let you truncate a file that you
+			* currently lack permissions for, even if you
+			* had permissions when you opened it.
+			* Also, Posix 1003.1b-1993 sec 5.6.7.2 p 128 l 1022
+			* says ftruncate might fail because it's not supported.
+			*/
+#			if !has_ftruncate
+#			    undef ftruncate
+#			    define ftruncate(fd,length) (-1)
+#			endif
+			bad_truncate = ftruncate(fileno(frewrite), (off_t)0);
+
+			Irewind(finptr);
+			Lexinit();
+			getadmin();
+			gettree();
+			if (!(workdelta = genrevs(
+			    targetdelta->num, (char*)0, (char*)0, (char*)0,
+			    &gendeltas
+			)))
+			    continue;
+			workdelta->log = targetdelta->log;
+			if (newdelta.state != default_state)
+			    workdelta->state = newdelta.state;
+			if (lockthis<removedlock && removelock(workdelta)<0)
+			    continue;
+			if (!addsyms(workdelta->num))
+			    continue;
+			if (dorewrite(true, true) != 0)
+			    continue;
+			fastcopy(finptr, frewrite);
+			if (bad_truncate)
+			    while (ftell(frewrite) < hwm)
+				/* White out any earlier mistake with '\n's.  */
+				/* This is unlikely.  */
+				afputc('\n', frewrite);
+		    }
+		} else {
+		    int wfd = Ifileno(workptr);
+		    struct stat checkworkstat;
+		    char const *diffv[6 + !!OPEN_O_BINARY], **diffp;
+#		    if large_memory && !maps_memory
+			FILE *wfile = workptr->stream;
+			long wfile_off;
+#		    endif
+#		    if !has_fflush_input && !(large_memory && maps_memory)
+		        off_t wfd_off;
+#		    endif
+
+		    diagnose("new revision: %s; previous revision: %s\n",
+			newdelta.num, targetdelta->num
+		    );
+		    newdelta.log = getlogmsg();
+#		    if !large_memory
+			Irewind(workptr);
+#			if has_fflush_input
+			    if (fflush(workptr) != 0)
+				Ierror();
+#			endif
+#		    else
+#			if !maps_memory
+			    if (
+			    	(wfile_off = ftell(wfile)) == -1
+			     ||	fseek(wfile, 0L, SEEK_SET) != 0
+#			     if has_fflush_input
+			     ||	fflush(wfile) != 0
+#			     endif
+			    )
+				Ierror();
+#			endif
+#		    endif
+#		    if !has_fflush_input && !(large_memory && maps_memory)
+			wfd_off = lseek(wfd, (off_t)0, SEEK_CUR);
+			if (wfd_off == -1
+			    || (wfd_off != 0
+				&& lseek(wfd, (off_t)0, SEEK_SET) != 0))
+			    Ierror();
+#		    endif
+		    diffp = diffv;
+		    *++diffp = DIFF;
+		    *++diffp = DIFFFLAGS;
+#		    if OPEN_O_BINARY
+			if (Expand == BINARY_EXPAND)
+			    *++diffp = "--binary";
+#		    endif
+		    *++diffp = newhead ? "-" : expname;
+		    *++diffp = newhead ? expname : "-";
+		    *++diffp = 0;
+		    switch (runv(wfd, diffname, diffv)) {
+			case DIFF_FAILURE: case DIFF_SUCCESS: break;
+			default: rcsfaterror("diff failed");
+		    }
+#		    if !has_fflush_input && !(large_memory && maps_memory)
+			if (lseek(wfd, wfd_off, SEEK_CUR) == -1)
+			    Ierror();
+#		    endif
+#		    if large_memory && !maps_memory
+			if (fseek(wfile, wfile_off, SEEK_SET) != 0)
+			    Ierror();
+#		    endif
+		    if (newhead) {
+			Irewind(workptr);
+			putdftext(&newdelta, workptr, frewrite, false);
+			if (!putdtext(targetdelta,diffname,frewrite,true)) continue;
+		    } else
+			if (!putdtext(&newdelta,diffname,frewrite,true)) continue;
+
+		    /*
+		    * Check whether the working file changed during checkin,
+		    * to avoid producing an inconsistent RCS file.
+		    */
+		    if (
+			fstat(wfd, &checkworkstat) != 0
+		     ||	workstat.st_mtime != checkworkstat.st_mtime
+		     ||	workstat.st_size != checkworkstat.st_size
+		    ) {
+			workerror("file changed during checkin");
+			continue;
+		    }
+
+		    changedRCS = true;
+                }
+        }
+
+	/* Deduce time_t of new revision if it is needed later.  */
+	wtime = (time_t)-1;
+	if (mtimeflag | Ttimeflag)
+		wtime = date2time(workdelta->date);
+
+	if (donerewrite(changedRCS,
+		!Ttimeflag ? (time_t)-1
+		: finptr && wtime < RCSstat.st_mtime ? RCSstat.st_mtime
+		: wtime
+	) != 0)
+		continue;
+
+        if (!keepworkingfile) {
+		Izclose(&workptr);
+		r = un_link(workname); /* Get rid of old file */
+        } else {
+		newworkmode = WORKMODE(RCSstat.st_mode,
+			!   (Expand==VAL_EXPAND  ||  lockthis < StrictLocks)
+		);
+		mtime = mtimeflag ? wtime : (time_t)-1;
+
+		/* Expand if it might change or if we can't fix mode, time.  */
+		if (changework  ||  (r=fixwork(newworkmode,mtime)) != 0) {
+		    Irewind(workptr);
+		    /* Expand keywords in file.  */
+		    locker_expansion = lockthis;
+		    workdelta->name =
+			namedrev(
+				assoclst ? assoclst->ssymbol
+				: keepflag && *prevname.string ? prevname.string
+				: rev,
+				workdelta
+			);
+		    switch (xpandfile(
+			workptr, workdelta, &newworkname, dolog
+		    )) {
+			default:
+			    continue;
+
+			case 0:
+			    /*
+			     * No expansion occurred; try to reuse working file
+			     * unless we already tried and failed.
+			     */
+			    if (changework)
+				if ((r=fixwork(newworkmode,mtime)) == 0)
+				    break;
+			    /* fall into */
+			case 1:
+			    Izclose(&workptr);
+			    aflush(exfile);
+			    ignoreints();
+			    r = chnamemod(&exfile, newworkname,
+				    workname, 1, newworkmode, mtime
+			    );
+			    keepdirtemp(newworkname);
+			    restoreints();
+		    }
+		}
+        }
+	if (r != 0) {
+	    eerror(workname);
+	    continue;
+	}
+	diagnose("done\n");
+
+	}
+
+	tempunlink();
+	exitmain(exitstatus);
+}       /* end of main (ci) */
+
+	static void
+cleanup()
+{
+	if (nerror) exitstatus = EXIT_FAILURE;
+	Izclose(&finptr);
+	Izclose(&workptr);
+	Ozclose(&exfile);
+	Ozclose(&fcopy);
+	ORCSclose();
+	dirtempunlink();
+}
+
+#if RCS_lint
+#	define exiterr ciExit
+#endif
+	void
+exiterr()
+{
+	ORCSerror();
+	dirtempunlink();
+	tempunlink();
+	_exit(EXIT_FAILURE);
+}
+
+/*****************************************************************/
+/* the rest are auxiliary routines                               */
+
+
+	static int
+addelta()
+/* Function: Appends a delta to the delta tree, whose number is
+ * given by newdelnum.  Updates Head, newdelnum, newdelnumlength,
+ * and the links in newdelta.
+ * Return -1 on error, 1 if a lock is removed, 0 otherwise.
+ */
+{
+	register char *tp;
+	register int i;
+	int removedlock;
+	int newdnumlength;  /* actual length of new rev. num. */
+
+	newdnumlength = countnumflds(newdelnum.string);
+
+	if (rcsinitflag) {
+                /* this covers non-existing RCS file and a file initialized with rcs -i */
+		if (newdnumlength==0 && Dbranch) {
+			bufscpy(&newdelnum, Dbranch);
+			newdnumlength = countnumflds(Dbranch);
+		}
+		if (newdnumlength==0) bufscpy(&newdelnum, "1.1");
+		else if (newdnumlength==1) bufscat(&newdelnum, ".1");
+		else if (newdnumlength>2) {
+		    rcserror("Branch point doesn't exist for revision %s.",
+			newdelnum.string
+		    );
+		    return -1;
+                } /* newdnumlength == 2 is OK;  */
+                Head = &newdelta;
+		newdelta.next = 0;
+		return 0;
+        }
+        if (newdnumlength==0) {
+                /* derive new revision number from locks */
+		switch (findlock(true, &targetdelta)) {
+
+		  default:
+		    /* found two or more old locks */
+		    return -1;
+
+		  case 1:
+                    /* found an old lock */
+                    /* check whether locked revision exists */
+		    if (!genrevs(targetdelta->num,(char*)0,(char*)0,(char*)0,&gendeltas))
+			return -1;
+                    if (targetdelta==Head) {
+                        /* make new head */
+                        newdelta.next=Head;
+                        Head= &newdelta;
+		    } else if (!targetdelta->next && countnumflds(targetdelta->num)>2) {
+                        /* new tip revision on side branch */
+                        targetdelta->next= &newdelta;
+			newdelta.next = 0;
+                    } else {
+                        /* middle revision; start a new branch */
+			bufscpy(&newdelnum, "");
+			return addbranch(targetdelta, &newdelnum, 1);
+                    }
+		    incnum(targetdelta->num, &newdelnum);
+		    return 1; /* successful use of existing lock */
+
+		  case 0:
+                    /* no existing lock; try Dbranch */
+                    /* update newdelnum */
+		    if (StrictLocks || !myself(RCSstat.st_uid)) {
+			rcserror("no lock set by %s", getcaller());
+			return -1;
+                    }
+                    if (Dbranch) {
+			bufscpy(&newdelnum, Dbranch);
+                    } else {
+			incnum(Head->num, &newdelnum);
+                    }
+		    newdnumlength = countnumflds(newdelnum.string);
+                    /* now fall into next statement */
+                }
+        }
+        if (newdnumlength<=2) {
+                /* add new head per given number */
+                if(newdnumlength==1) {
+                    /* make a two-field number out of it*/
+		    if (cmpnumfld(newdelnum.string,Head->num,1)==0)
+			incnum(Head->num, &newdelnum);
+		    else
+			bufscat(&newdelnum, ".1");
+                }
+		if (cmpnum(newdelnum.string,Head->num) <= 0) {
+		    rcserror("revision %s too low; must be higher than %s",
+			  newdelnum.string, Head->num
+		    );
+		    return -1;
+                }
+		targetdelta = Head;
+		if (0 <= (removedlock = removelock(Head))) {
+		    if (!genrevs(Head->num,(char*)0,(char*)0,(char*)0,&gendeltas))
+			return -1;
+		    newdelta.next = Head;
+		    Head = &newdelta;
+		}
+		return removedlock;
+        } else {
+                /* put new revision on side branch */
+                /*first, get branch point */
+		tp = newdelnum.string;
+		for (i = newdnumlength - ((newdnumlength&1) ^ 1);  --i;  )
+			while (*tp++ != '.')
+				continue;
+		*--tp = 0; /* Kill final dot to get old delta temporarily. */
+		if (!(targetdelta=genrevs(newdelnum.string,(char*)0,(char*)0,(char*)0,&gendeltas)))
+		    return -1;
+		if (cmpnum(targetdelta->num, newdelnum.string) != 0) {
+		    rcserror("can't find branch point %s", newdelnum.string);
+		    return -1;
+                }
+		*tp = '.'; /* Restore final dot. */
+		return addbranch(targetdelta, &newdelnum, 0);
+        }
+}
+
+
+
+	static int
+addbranch(branchpoint, num, removedlock)
+	struct hshentry *branchpoint;
+	struct buf *num;
+	int removedlock;
+/* adds a new branch and branch delta at branchpoint.
+ * If num is the null string, appends the new branch, incrementing
+ * the highest branch number (initially 1), and setting the level number to 1.
+ * the new delta and branchhead are in globals newdelta and newbranch, resp.
+ * the new number is placed into num.
+ * Return -1 on error, 1 if a lock is removed, 0 otherwise.
+ * If REMOVEDLOCK is 1, a lock was already removed.
+ */
+{
+	struct branchhead *bhead, **btrail;
+	struct buf branchnum;
+	int result;
+	int field, numlength;
+	static struct branchhead newbranch;  /* new branch to be inserted */
+
+	numlength = countnumflds(num->string);
+
+	if (!branchpoint->branches) {
+                /* start first branch */
+                branchpoint->branches = &newbranch;
+                if (numlength==0) {
+			bufscpy(num, branchpoint->num);
+			bufscat(num, ".1.1");
+		} else if (numlength&1)
+			bufscat(num, ".1");
+		newbranch.nextbranch = 0;
+
+	} else if (numlength==0) {
+                /* append new branch to the end */
+                bhead=branchpoint->branches;
+                while (bhead->nextbranch) bhead=bhead->nextbranch;
+                bhead->nextbranch = &newbranch;
+		bufautobegin(&branchnum);
+		getbranchno(bhead->hsh->num, &branchnum);
+		incnum(branchnum.string, num);
+		bufautoend(&branchnum);
+		bufscat(num, ".1");
+		newbranch.nextbranch = 0;
+        } else {
+                /* place the branch properly */
+		field = numlength - ((numlength&1) ^ 1);
+                /* field of branch number */
+		btrail = &branchpoint->branches;
+		while (0 < (result=cmpnumfld(num->string,(*btrail)->hsh->num,field))) {
+			btrail = &(*btrail)->nextbranch;
+			if (!*btrail) {
+				result = -1;
+				break;
+			}
+                }
+		if (result < 0) {
+                        /* insert/append new branchhead */
+			newbranch.nextbranch = *btrail;
+			*btrail = &newbranch;
+			if (numlength&1) bufscat(num, ".1");
+                } else {
+                        /* branch exists; append to end */
+			bufautobegin(&branchnum);
+			getbranchno(num->string, &branchnum);
+			targetdelta = genrevs(
+				branchnum.string, (char*)0, (char*)0, (char*)0,
+				&gendeltas
+			);
+			bufautoend(&branchnum);
+			if (!targetdelta)
+			    return -1;
+			if (cmpnum(num->string,targetdelta->num) <= 0) {
+				rcserror("revision %s too low; must be higher than %s",
+				      num->string, targetdelta->num
+				);
+				return -1;
+                        }
+			if (!removedlock
+			    && 0 <= (removedlock = removelock(targetdelta))
+			) {
+			    if (numlength&1)
+				incnum(targetdelta->num,num);
+			    targetdelta->next = &newdelta;
+			    newdelta.next = 0;
+			}
+			return removedlock;
+			/* Don't do anything to newbranch.  */
+                }
+        }
+        newbranch.hsh = &newdelta;
+	newdelta.next = 0;
+	if (branchpoint->lockedby)
+	    if (strcmp(branchpoint->lockedby, getcaller()) == 0)
+		return removelock(branchpoint); /* This returns 1.  */
+	return removedlock;
+}
+
+	static int
+addsyms(num)
+	char const *num;
+{
+	register struct Symrev *p;
+
+	for (p = assoclst;  p;  p = p->nextsym)
+		if (addsymbol(num, p->ssymbol, p->override)  <  0)
+			return false;
+	return true;
+}
+
+
+	static void
+incnum(onum,nnum)
+	char const *onum;
+	struct buf *nnum;
+/* Increment the last field of revision number onum by one and
+ * place the result into nnum.
+ */
+{
+	register char *tp, *np;
+	register size_t l;
+
+	l = strlen(onum);
+	bufalloc(nnum, l+2);
+	np = tp = nnum->string;
+	VOID strcpy(np, onum);
+	for (tp = np + l;  np != tp;  )
+		if (isdigit(*--tp)) {
+			if (*tp != '9') {
+				++*tp;
+				return;
+			}
+			*tp = '0';
+		} else {
+			tp++;
+			break;
+		}
+	/* We changed 999 to 000; now change it to 1000.  */
+	*tp = '1';
+	tp = np + l;
+	*tp++ = '0';
+	*tp = 0;
+}
+
+
+
+	static int
+removelock(delta)
+struct hshentry * delta;
+/* function: Finds the lock held by caller on delta,
+ * removes it, and returns nonzero if successful.
+ * Print an error message and return -1 if there is no such lock.
+ * An exception is if !StrictLocks, and caller is the owner of
+ * the RCS file. If caller does not have a lock in this case,
+ * return 0; return 1 if a lock is actually removed.
+ */
+{
+	register struct rcslock *next, **trail;
+	char const *num;
+
+        num=delta->num;
+	for (trail = &Locks;  (next = *trail);  trail = &next->nextlock)
+	    if (next->delta == delta)
+		if (strcmp(getcaller(), next->login) == 0) {
+		    /* We found a lock on delta by caller; delete it.  */
+		    *trail = next->nextlock;
+		    delta->lockedby = 0;
+		    return 1;
+		} else {
+		    rcserror("revision %s locked by %s", num, next->login);
+		    return -1;
+                }
+	if (!StrictLocks && myself(RCSstat.st_uid))
+	    return 0;
+	rcserror("no lock set by %s for revision %s", getcaller(), num);
+	return -1;
+}
+
+
+
+	static char const *
+getcurdate()
+/* Return a pointer to the current date.  */
+{
+	static char buffer[datesize]; /* date buffer */
+
+	if (!buffer[0])
+		time2date(now(), buffer);
+        return buffer;
+}
+
+	static int
+#if has_prototypes
+fixwork(mode_t newworkmode, time_t mtime)
+  /* The `#if has_prototypes' is needed because mode_t might promote to int.  */
+#else
+  fixwork(newworkmode, mtime)
+	mode_t newworkmode;
+	time_t mtime;
+#endif
+{
+	return
+			1 < workstat.st_nlink
+		    ||	(newworkmode&S_IWUSR && !myself(workstat.st_uid))
+		    ||	setmtime(workname, mtime) != 0
+		?   -1
+	    :	workstat.st_mode == newworkmode  ?  0
+#if has_fchmod
+	    :	fchmod(Ifileno(workptr), newworkmode) == 0  ?  0
+#endif
+#if bad_chmod_close
+	    :	-1
+#else
+	    :	chmod(workname, newworkmode)
+#endif
+	;
+}
+
+	static int
+xpandfile(unexfile, delta, exname, dolog)
+	RILE *unexfile;
+	struct hshentry const *delta;
+	char const **exname;
+	int dolog;
+/*
+ * Read unexfile and copy it to a
+ * file, performing keyword substitution with data from delta.
+ * Return -1 if unsuccessful, 1 if expansion occurred, 0 otherwise.
+ * If successful, stores the stream descriptor into *EXFILEP
+ * and its name into *EXNAME.
+ */
+{
+	char const *targetname;
+	int e, r;
+
+	targetname = makedirtemp(1);
+	if (!(exfile = fopenSafer(targetname, FOPEN_W_WORK))) {
+		eerror(targetname);
+		workerror("can't build working file");
+		return -1;
+        }
+	r = 0;
+	if (MIN_UNEXPAND <= Expand)
+		fastcopy(unexfile,exfile);
+	else {
+		for (;;) {
+			e = expandline(
+				unexfile, exfile, delta, false, (FILE*)0, dolog
+			);
+			if (e < 0)
+				break;
+			r |= e;
+			if (e <= 1)
+				break;
+		}
+	}
+	*exname = targetname;
+	return r & 1;
+}
+
+
+
+
+/* --------------------- G E T L O G M S G --------------------------------*/
+
+
+	static struct cbuf
+getlogmsg()
+/* Obtain and yield a log message.
+ * If a log message is given with -m, yield that message.
+ * If this is the initial revision, yield a standard log message.
+ * Otherwise, reads a character string from the terminal.
+ * Stops after reading EOF or a single '.' on a
+ * line. getlogmsg prompts the first time it is called for the
+ * log message; during all later calls it asks whether the previous
+ * log message can be reused.
+ */
+{
+	static char const
+		emptych[] = EMPTYLOG,
+		initialch[] = "Initial revision";
+	static struct cbuf const
+		emptylog = { emptych, sizeof(emptych)-sizeof(char) },
+		initiallog = { initialch, sizeof(initialch)-sizeof(char) };
+	static struct buf logbuf;
+	static struct cbuf logmsg;
+
+	register char *tp;
+	register size_t i;
+	char const *caller;
+
+	if (msg.size) return msg;
+
+	if (keepflag) {
+		/* generate std. log message */
+		caller = getcaller();
+		i = sizeof(ciklog)+strlen(caller)+3;
+		bufalloc(&logbuf, i + datesize + zonelenmax);
+		tp = logbuf.string;
+		VOID sprintf(tp, "%s%s at ", ciklog, caller);
+		VOID date2str(getcurdate(), tp+i);
+		logmsg.string = tp;
+		logmsg.size = strlen(tp);
+		return logmsg;
+	}
+
+	if (!targetdelta && (
+		cmpnum(newdelnum.string,"1.1")==0 ||
+		cmpnum(newdelnum.string,"1.0")==0
+	))
+		return initiallog;
+
+	if (logmsg.size) {
+                /*previous log available*/
+	    if (yesorno(true, "reuse log message of previous file? [yn](y): "))
+		return logmsg;
+        }
+
+        /* now read string from stdin */
+	logmsg = getsstdin("m", "log message", "", &logbuf);
+
+        /* now check whether the log message is not empty */
+	if (logmsg.size)
+		return logmsg;
+	return emptylog;
+}
+
+/*  Make a linked list of Symbolic names  */
+
+        static void
+addassoclst(flag, sp)
+	int flag;
+	char const *sp;
+{
+        struct Symrev *pt;
+
+	pt = talloc(struct Symrev);
+	pt->ssymbol = sp;
+	pt->override = flag;
+	pt->nextsym = 0;
+	*nextassoc = pt;
+	nextassoc = &pt->nextsym;
+}
diff --git a/gnu/usr.bin/rcs/co/Makefile b/gnu/usr.bin/rcs/co/Makefile
new file mode 100644
index 0000000000000..0c73865d09fcc
--- /dev/null
+++ b/gnu/usr.bin/rcs/co/Makefile
@@ -0,0 +1,8 @@
+PROG=	co
+SRCS=	co.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=	${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/co/co.1 b/gnu/usr.bin/rcs/co/co.1
new file mode 100644
index 0000000000000..2aea3ad1b40da
--- /dev/null
+++ b/gnu/usr.bin/rcs/co/co.1
@@ -0,0 +1,736 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds i \&\s-1ISO\s0
+.ds r \&\s-1RCS\s0
+.ds u \&\s-1UTC\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH CO 1 \*(Dt GNU
+.SH NAME
+co \- check out RCS revisions
+.SH SYNOPSIS
+.B co
+.RI [ options ] " file " .\|.\|.
+.SH DESCRIPTION
+.B co
+retrieves a revision from each \*r file and stores it into
+the corresponding working file.
+.PP
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+Names are paired as explained in
+.BR ci (1).
+.PP
+Revisions of an \*r file can be checked out locked or unlocked.  Locking a
+revision prevents overlapping updates.  A revision checked out for reading or
+processing (e.g., compiling) need not be locked.  A revision checked out
+for editing and later checkin must normally be locked.  Checkout with locking
+fails if the revision to be checked out is currently locked by another user.
+(A lock can be broken with
+.BR rcs "(1).)\ \&"
+Checkout with locking also requires the caller to be on the access list of
+the \*r file, unless he is the owner of the
+file or the superuser, or the access list is empty.
+Checkout without locking is not subject to accesslist restrictions, and is
+not affected by the presence of locks.
+.PP
+A revision is selected by options for revision or branch number,
+checkin date/time, author, or state.
+When the selection options
+are applied in combination,
+.B co
+retrieves the latest revision
+that satisfies all of them.
+If none of the selection options
+is specified,
+.B co
+retrieves the latest revision
+on the default branch (normally the trunk, see the
+.B \-b
+option of
+.BR rcs (1)).
+A revision or branch number can be attached
+to any of the options
+.BR \-f ,
+.BR \-I ,
+.BR \-l ,
+.BR \-M ,
+.BR \-p ,
+.BR \-q ,
+.BR \-r ,
+or
+.BR \-u .
+The options
+.B \-d
+(date),
+.B \-s
+(state), and
+.B \-w
+(author)
+retrieve from a single branch, the
+.I selected
+branch,
+which is either specified by one of
+.BR \-f ,
+\&.\|.\|.,
+.BR \-u ,
+or the default branch.
+.PP
+A
+.B co
+command applied to an \*r
+file with no revisions creates a zero-length working file.
+.B co
+always performs keyword substitution (see below).
+.SH OPTIONS
+.TP
+.BR \-r [\f2rev\fP]
+retrieves the latest revision whose number is less than or equal to
+.IR rev .
+If
+.I rev
+indicates a branch rather than a revision,
+the latest revision on that branch is retrieved.
+If
+.I rev
+is omitted, the latest revision on the default branch
+(see the
+.B \-b
+option of
+.BR rcs (1))
+is retrieved.
+If
+.I rev
+is
+.BR $ ,
+.B co
+determines the revision number from keyword values in the working file.
+Otherwise, a revision is composed of one or more numeric or symbolic fields
+separated by periods.
+If
+.I rev
+begins with a period,
+then the default branch (normally the trunk) is prepended to it.
+If
+.I rev
+is a branch number followed by a period,
+then the latest revision on that branch is used.
+The numeric equivalent of a symbolic field
+is specified with the
+.B \-n
+option of the commands
+.BR ci (1)
+and
+.BR rcs (1).
+.TP
+.BR \-l [\f2rev\fP]
+same as
+.BR \-r ,
+except that it also locks the retrieved revision for
+the caller.
+.TP
+.BR \-u [\f2rev\fP]
+same as
+.BR \-r ,
+except that it unlocks the retrieved revision if it was
+locked by the caller.  If
+.I rev
+is omitted,
+.B \-u
+retrieves the revision locked by the caller, if there is one; otherwise,
+it retrieves the latest revision on the default branch.
+.TP
+.BR \-f [\f2rev\fP]
+forces the overwriting of the working file;
+useful in connection with
+.BR \-q .
+See also
+.SM "FILE MODES"
+below.
+.TP
+.B \-kkv
+Generate keyword strings using the default form, e.g.\&
+.B "$\&Revision: \*(Rv $"
+for the
+.B Revision
+keyword.
+A locker's name is inserted in the value of the
+.BR Header ,
+.BR Id ,
+and
+.B Locker
+keyword strings
+only as a file is being locked,
+i.e. by
+.B "ci\ \-l"
+and
+.BR "co\ \-l".
+This is the default.
+.TP
+.B \-kkvl
+Like
+.BR \-kkv ,
+except that a locker's name is always inserted
+if the given revision is currently locked.
+.TP
+.B \-kk
+Generate only keyword names in keyword strings; omit their values.
+See
+.SM "KEYWORD SUBSTITUTION"
+below.
+For example, for the
+.B Revision
+keyword, generate the string
+.B $\&Revision$
+instead of
+.BR "$\&Revision: \*(Rv $" .
+This option is useful to ignore differences due to keyword substitution
+when comparing different revisions of a file.
+Log messages are inserted after
+.B $\&Log$
+keywords even if
+.B \-kk
+is specified,
+since this tends to be more useful when merging changes.
+.TP
+.B \-ko
+Generate the old keyword string,
+present in the working file just before it was checked in.
+For example, for the
+.B Revision
+keyword, generate the string
+.B "$\&Revision: 1.1 $"
+instead of
+.B "$\&Revision: \*(Rv $"
+if that is how the string appeared when the file was checked in.
+This can be useful for file formats
+that cannot tolerate any changes to substrings
+that happen to take the form of keyword strings.
+.TP
+.B \-kb
+Generate a binary image of the old keyword string.
+This acts like
+.BR \-ko ,
+except it performs all working file input and output in binary mode.
+This makes little difference on Posix and Unix hosts,
+but on DOS-like hosts one should use
+.B "rcs\ \-i\ \-kb"
+to initialize an \*r file intended to be used for binary files.
+Also, on all hosts,
+.BR rcsmerge (1)
+normally refuses to merge files when
+.B \-kb
+is in effect.
+.TP
+.B \-kv
+Generate only keyword values for keyword strings.
+For example, for the
+.B Revision
+keyword, generate the string
+.B \*(Rv
+instead of
+.BR "$\&Revision: \*(Rv $" .
+This can help generate files in programming languages where it is hard to
+strip keyword delimiters like
+.B "$\&Revision:\ $"
+from a string.
+However, further keyword substitution cannot be performed once the
+keyword names are removed, so this option should be used with care.
+Because of this danger of losing keywords,
+this option cannot be combined with
+.BR \-l ,
+and the owner write permission of the working file is turned off;
+to edit the file later, check it out again without
+.BR \-kv .
+.TP
+.BR \-p [\f2rev\fP]
+prints the retrieved revision on the standard output rather than storing it
+in the working file.
+This option is useful when
+.B co
+is part of a pipe.
+.TP
+.BR \-q [\f2rev\fP]
+quiet mode; diagnostics are not printed.
+.TP
+.BR \-I [\f2rev\fP]
+interactive mode;
+the user is prompted and questioned
+even if the standard input is not a terminal.
+.TP
+.BI \-d date
+retrieves the latest revision on the selected branch whose checkin date/time is
+less than or equal to
+.IR date .
+The date and time can be given in free format.
+The time zone
+.B LT
+stands for local time;
+other common time zone names are understood.
+For example, the following
+.IR date s
+are equivalent
+if local time is January 11, 1990, 8pm Pacific Standard Time,
+eight hours west of Coordinated Universal Time (\*u):
+.RS
+.LP
+.RS
+.nf
+.ta \w'\f3Thu, 11 Jan 1990 20:00:00 \-0800\fP  'u
+.ne 10
+\f38:00 pm lt\fP
+\f34:00 AM, Jan. 12, 1990\fP	default is \*u
+\f31990-01-12 04:00:00+00\fP	\*i 8601 (\*u)
+\f31990-01-11 20:00:00\-08\fP	\*i 8601 (local time)
+\f31990/01/12 04:00:00\fP	traditional \*r format
+\f3Thu Jan 11 20:00:00 1990 LT\fP	output of \f3ctime\fP(3) + \f3LT\fP
+\f3Thu Jan 11 20:00:00 PST 1990\fP	output of \f3date\fP(1)
+\f3Fri Jan 12 04:00:00 GMT 1990\fP
+\f3Thu, 11 Jan 1990 20:00:00 \-0800\fP	Internet RFC 822
+\f312-January-1990, 04:00 WET\fP
+.ta 4n +4n +4n +4n
+.fi
+.RE
+.LP
+Most fields in the date and time can be defaulted.
+The default time zone is normally \*u, but this can be overridden by the
+.B \-z
+option.
+The other defaults are determined in the order year, month, day,
+hour, minute, and second (most to least significant).  At least one of these
+fields must be provided.  For omitted fields that are of higher significance
+than the highest provided field, the time zone's current values are assumed.
+For all other omitted fields,
+the lowest possible values are assumed.
+For example, without
+.BR \-z ,
+the date
+.B "20, 10:30"
+defaults to
+10:30:00 \*u of the 20th of the \*u time zone's current month and year.
+The date/time must be quoted if it contains spaces.
+.RE
+.TP
+.BR \-M [\f2rev\fP]
+Set the modification time on the new working file
+to be the date of the retrieved revision.
+Use this option with care; it can confuse
+.BR make (1).
+.TP
+.BI \-s state
+retrieves the latest revision on the selected branch whose state is set to
+.IR state .
+.TP
+.B \-T
+Preserve the modification time on the \*r file
+even if the \*r file changes because a lock is added or removed.
+This option can suppress extensive recompilation caused by a
+.BR make (1)
+dependency of some other copy of the working file on the \*r file.
+Use this option with care; it can suppress recompilation even when it is needed,
+i.e. when the change of lock
+would mean a change to keyword strings in the other working file.
+.TP
+.BR \-w [\f2login\fP]
+retrieves the latest revision on the selected branch which was checked in
+by the user with login name
+.IR login .
+If the argument
+.I login
+is
+omitted, the caller's login is assumed.
+.TP
+.BI \-j joinlist
+generates a new revision which is the join of the revisions on
+.IR joinlist .
+This option is largely obsoleted by
+.BR rcsmerge (1)
+but is retained for backwards compatibility.
+.RS
+.PP
+The
+.I joinlist
+is a comma-separated list of pairs of the form
+.IB rev2 : rev3,
+where
+.I rev2
+and
+.I rev3
+are (symbolic or numeric)
+revision numbers.
+For the initial such pair,
+.I rev1
+denotes the revision selected
+by the above options
+.BR \-f ,
+\&.\|.\|.,
+.BR \-w .
+For all other pairs,
+.I rev1
+denotes the revision generated by the previous pair.
+(Thus, the output
+of one join becomes the input to the next.)
+.PP
+For each pair,
+.B co
+joins revisions
+.I rev1
+and
+.I rev3
+with respect to
+.IR rev2 .
+This means that all changes that transform
+.I rev2
+into
+.I rev1
+are applied to a copy of
+.IR rev3 .
+This is particularly useful if
+.I rev1
+and
+.I rev3
+are the ends of two branches that have
+.I rev2
+as a common ancestor.  If
+.IR rev1 < rev2 < rev3
+on the same branch,
+joining generates a new revision which is like
+.I rev3,
+but with all changes that lead from
+.I rev1
+to
+.I rev2
+undone.
+If changes from
+.I rev2
+to
+.I rev1
+overlap with changes from
+.I rev2
+to
+.I rev3,
+.B co
+reports overlaps as described in
+.BR merge (1).
+.PP
+For the initial pair,
+.I rev2
+can be omitted.  The default is the common
+ancestor.
+If any of the arguments indicate branches, the latest revisions
+on those branches are assumed.
+The options
+.B \-l
+and
+.B \-u
+lock or unlock
+.IR rev1 .
+.RE
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.I n,
+where
+.I n
+can be
+.BR 3 ,
+.BR 4 ,
+or
+.BR 5 .
+This can be useful when interchanging \*r files with others who are
+running older versions of \*r.
+To see which version of \*r your correspondents are running, have them invoke
+.BR "rcs \-V" ;
+this works with newer versions of \*r.
+If it doesn't work, have them invoke
+.B rlog
+on an \*r file;
+if none of the first few lines of output contain the string
+.B branch:
+it is version 3;
+if the dates' years have just two digits, it is version 4;
+otherwise, it is version 5.
+An \*r file generated while emulating version 3 loses its default branch.
+An \*r revision generated while emulating version 4 or earlier has
+a time stamp that is off by up to 13 hours.
+A revision extracted while emulating version 4 or earlier contains
+abbreviated dates of the form
+.IB yy / mm / dd
+and can also contain different white space and line prefixes
+in the substitution for
+.BR $\&Log$ .
+.TP
+.BI \-x "suffixes"
+Use
+.I suffixes
+to characterize \*r files.
+See
+.BR ci (1)
+for details.
+.TP
+.BI \-z zone
+specifies the date output format in keyword substitution,
+and specifies the default time zone for
+.I date
+in the
+.BI \-d date
+option.
+The
+.I zone
+should be empty, a numeric \*u offset, or the special string
+.B LT
+for local time.
+The default is an empty
+.IR zone ,
+which uses the traditional \*r format of \*u without any time zone indication
+and with slashes separating the parts of the date;
+otherwise, times are output in \*i 8601 format with time zone indication.
+For example, if local time is January 11, 1990, 8pm Pacific Standard Time,
+eight hours west of \*u,
+then the time is output as follows:
+.RS
+.LP
+.RS
+.nf
+.ta \w'\f3\-z+05:30\fP  'u +\w'\f31990-01-11 09:30:00+05:30\fP  'u
+.ne 4
+\f2option\fP	\f2time output\fP
+\f3\-z\fP	\f31990/01/12 04:00:00\fP	\f2(default)\fP
+\f3\-zLT\fP	\f31990-01-11 20:00:00\-08\fP
+\f3\-z+05:30\fP	\f31990-01-12 09:30:00+05:30\fP
+.ta 4n +4n +4n +4n
+.fi
+.RE
+.LP
+The
+.B \-z
+option does not affect dates stored in \*r files,
+which are always \*u.
+.RE
+.SH "KEYWORD SUBSTITUTION"
+Strings of the form
+.BI $ keyword $
+and
+.BI $ keyword : .\|.\|. $
+embedded in
+the text are replaced
+with strings of the form
+.BI $ keyword : value $
+where
+.I keyword
+and
+.I value
+are pairs listed below.
+Keywords can be embedded in literal strings
+or comments to identify a revision.
+.PP
+Initially, the user enters strings of the form
+.BI $ keyword $ .
+On checkout,
+.B co
+replaces these strings with strings of the form
+.BI $ keyword : value $ .
+If a revision containing strings of the latter form
+is checked back in, the value fields will be replaced during the next
+checkout.
+Thus, the keyword values are automatically updated on checkout.
+This automatic substitution can be modified by the
+.B \-k
+options.
+.PP
+Keywords and their corresponding values:
+.TP
+.B $\&Author$
+The login name of the user who checked in the revision.
+.TP
+.B $\&Date$
+The date and time the revision was checked in.
+With
+.BI \-z zone
+a numeric time zone offset is appended; otherwise, the date is \*u.
+.TP
+.B $\&Header$
+A standard header containing the full pathname of the \*r file, the
+revision number, the date and time, the author, the state,
+and the locker (if locked).
+With
+.BI \-z zone
+a numeric time zone offset is appended to the date; otherwise, the date is \*u.
+.TP
+.B $\&Id$
+Same as
+.BR $\&Header$ ,
+except that the \*r filename is without a path.
+.TP
+.B $\&Locker$
+The login name of the user who locked the revision (empty if not locked).
+.TP
+.B $\&Log$
+The log message supplied during checkin, preceded by a header
+containing the \*r filename, the revision number, the author, and the date
+and time.
+With
+.BI \-z zone
+a numeric time zone offset is appended; otherwise, the date is \*u.
+Existing log messages are
+.I not
+replaced.
+Instead, the new log message is inserted after
+.BR $\&Log: .\|.\|. $ .
+This is useful for
+accumulating a complete change log in a source file.
+.RS
+.LP
+Each inserted line is prefixed by the string that prefixes the
+.B $\&Log$
+line.  For example, if the
+.B $\&Log$
+line is
+.RB \*(lq "//\ $\&Log: tan.cc\ $" \*(rq,
+\*r prefixes each line of the log with
+.RB \*(lq "//\ " \*(rq.
+This is useful for languages with comments that go to the end of the line.
+The convention for other languages is to use a
+.RB \*(lq " \(** " \(rq
+prefix inside a multiline comment.
+For example, the initial log comment of a C program
+conventionally is of the following form:
+.RS
+.LP
+.nf
+.ft 3
+.ne 3
+/\(**
+.in +\w'/'u
+\(** $\&Log$
+\(**/
+.in
+.ft
+.fi
+.RE
+.LP
+For backwards compatibility with older versions of \*r, if the log prefix is
+.B /\(**
+or
+.B (\(**
+surrounded by optional white space, inserted log lines contain a space
+instead of
+.B /
+or
+.BR ( ;
+however, this usage is obsolescent and should not be relied on.
+.RE
+.TP
+.B $\&Name$
+The symbolic name used to check out the revision, if any.
+For example,
+.B "co\ \-rJoe"
+generates
+.BR "$\&Name:\ Joe\ $" .
+Plain
+.B co
+generates just
+.BR "$\&Name:\ \ $" .
+.TP
+.B $\&RCSfile$
+The name of the \*r file without a path.
+.TP
+.B $\&Revision$
+The revision number assigned to the revision.
+.TP
+.B $\&Source$
+The full pathname of the \*r file.
+.TP
+.B $\&State$
+The state assigned to the revision with the
+.B \-s
+option of
+.BR rcs (1)
+or
+.BR ci (1).
+.PP
+The following characters in keyword values are represented by escape sequences
+to keep keyword strings well-formed.
+.LP
+.RS
+.nf
+.ne 6
+.ta \w'newline  'u
+\f2char	escape sequence\fP
+tab	\f3\et\fP
+newline	\f3\en\fP
+space	\f3\e040
+$	\e044
+\e	\e\e\fP
+.fi
+.RE
+.SH "FILE MODES"
+The working file inherits the read and execute permissions from the \*r
+file.  In addition, the owner write permission is turned on, unless
+.B \-kv
+is set or the file
+is checked out unlocked and locking is set to strict (see
+.BR rcs (1)).
+.PP
+If a file with the name of the working file exists already and has write
+permission,
+.B co
+aborts the checkout,
+asking beforehand if possible.
+If the existing working file is
+not writable or
+.B \-f
+is given, the working file is deleted without asking.
+.SH FILES
+.B co
+accesses files much as
+.BR ci (1)
+does, except that it does not need to read the working file
+unless a revision number of
+.B $
+is specified.
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+See
+.BR ci (1)
+for details.
+.SH DIAGNOSTICS
+The \*r pathname, the working pathname,
+and the revision number retrieved are
+written to the diagnostic output.
+The exit status is zero if and only if all operations were successful.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH "SEE ALSO"
+rcsintro(1), ci(1), ctime(3), date(1), ident(1), make(1),
+rcs(1), rcsclean(1), rcsdiff(1), rcsmerge(1), rlog(1),
+rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.SH LIMITS
+Links to the \*r and working files are not preserved.
+.PP
+There is no way to selectively suppress the expansion of keywords, except
+by writing them differently.  In nroff and troff, this is done by embedding the
+null-character
+.B \e&
+into the keyword.
+.br
diff --git a/gnu/usr.bin/rcs/co/co.c b/gnu/usr.bin/rcs/co/co.c
new file mode 100644
index 0000000000000..51cb2b277927e
--- /dev/null
+++ b/gnu/usr.bin/rcs/co/co.c
@@ -0,0 +1,826 @@
+/* Check out working files from revisions of RCS files.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.18  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.17  1995/06/01 16:23:43  eggert
+ * (main, preparejoin): Pass argument instead of using `join' static variable.
+ * (main): Add -kb.
+ *
+ * Revision 5.16  1994/03/17 14:05:48  eggert
+ * Move buffer-flushes out of critical sections, since they aren't critical.
+ * Use ORCSerror to clean up after a fatal error.  Remove lint.
+ * Specify subprocess input via file descriptor, not file name.
+ *
+ * Revision 5.15  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.  Don't print usage twice.
+ *
+ * Revision 5.14  1993/11/03 17:42:27  eggert
+ * Add -z.  Generate a value for the Name keyword.
+ * Don't arbitrarily limit the number of joins.
+ * Improve quality of diagnostics.
+ *
+ * Revision 5.13  1992/07/28  16:12:44  eggert
+ * Add -V.  Check that working and RCS files are distinct.
+ *
+ * Revision 5.12  1992/02/17  23:02:08  eggert
+ * Add -T.
+ *
+ * Revision 5.11  1992/01/24  18:44:19  eggert
+ * Add support for bad_creat0.  lint -> RCS_lint
+ *
+ * Revision 5.10  1992/01/06  02:42:34  eggert
+ * Update usage string.
+ *
+ * Revision 5.9  1991/10/07  17:32:46  eggert
+ * -k affects just working file, not RCS file.
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Warn before removing somebody else's file.
+ * Add -M.  Fix co -j bugs.  Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:15  eggert
+ * Ensure that working file is newer than RCS file after co -[lu].
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.6  1990/12/04  05:18:38  eggert
+ * Don't checkaccesslist() unless necessary.
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.5  1990/11/01  05:03:26  eggert
+ * Fix -j.  Add -I.
+ *
+ * Revision 5.4  1990/10/04  06:30:11  eggert
+ * Accumulate exit status across files.
+ *
+ * Revision 5.3  1990/09/11  02:41:09  eggert
+ * co -kv yields a readonly working file.
+ *
+ * Revision 5.2  1990/09/04  08:02:13  eggert
+ * Standardize yes-or-no procedure.
+ *
+ * Revision 5.0  1990/08/22  08:10:02  eggert
+ * Permit multiple locks by same user.  Add setuid support.
+ * Remove compile-time limits; use malloc instead.
+ * Permit dates past 1999/12/31.  Switch to GMT.
+ * Make lock and temp files faster and safer.
+ * Ansify and Posixate.  Add -k, -V.  Remove snooping.  Tune.
+ *
+ * Revision 4.7  89/05/01  15:11:41  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.6  88/08/09  19:12:15  eggert
+ * Fix "co -d" core dump; rawdate wasn't always initialized.
+ * Use execv(), not system(); fix putchar('\0') and diagnose() botches; remove lint
+ *
+ * Revision 4.5  87/12/18  11:35:40  narten
+ * lint cleanups (from Guy Harris)
+ *
+ * Revision 4.4  87/10/18  10:20:53  narten
+ * Updating version numbers changes relative to 1.1, are actually
+ * relative to 4.2
+ *
+ * Revision 1.3  87/09/24  13:58:30  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:21:38  jenkins
+ * Port to suns
+ *
+ * Revision 4.2  83/12/05  13:39:48  wft
+ * made rewriteflag external.
+ *
+ * Revision 4.1  83/05/10  16:52:55  wft
+ * Added option -u and -f.
+ * Added handling of default branch.
+ * Replaced getpwuid() with getcaller().
+ * Removed calls to stat(); now done by pairfilenames().
+ * Changed and renamed rmoldfile() to rmworkfile().
+ * Replaced catchints() calls with restoreints(), unlink()--link() with rename();
+ *
+ * Revision 3.7  83/02/15  15:27:07  wft
+ * Added call to fastcopy() to copy remainder of RCS file.
+ *
+ * Revision 3.6  83/01/15  14:37:50  wft
+ * Added ignoring of interrupts while RCS file is renamed; this avoids
+ * deletion of RCS files during the unlink/link window.
+ *
+ * Revision 3.5  82/12/08  21:40:11  wft
+ * changed processing of -d to use DATEFORM; removed actual from
+ * call to preparejoin; re-fixed printing of done at the end.
+ *
+ * Revision 3.4  82/12/04  18:40:00  wft
+ * Replaced getdelta() with gettree(), SNOOPDIR with SNOOPFILE.
+ * Fixed printing of "done".
+ *
+ * Revision 3.3  82/11/28  22:23:11  wft
+ * Replaced getlogin() with getpwuid(), flcose() with ffclose(),
+ * %02d with %.2d, mode generation for working file with WORKMODE.
+ * Fixed nil printing. Fixed -j combined with -l and -p, and exit
+ * for non-existing revisions in preparejoin().
+ *
+ * Revision 3.2  82/10/18  20:47:21  wft
+ * Mode of working file is now maintained even for co -l, but write permission
+ * is removed.
+ * The working file inherits its mode from the RCS file, plus write permission
+ * for the owner. The write permission is not given if locking is strict and
+ * co does not lock.
+ * An existing working file without write permission is deleted automatically.
+ * Otherwise, co asks (empty answer: abort co).
+ * Call to getfullRCSname() added, check for write error added, call
+ * for getlogin() fixed.
+ *
+ * Revision 3.1  82/10/13  16:01:30  wft
+ * fixed type of variables receiving from getc() (char -> int).
+ * removed unused variables.
+ */
+
+
+
+
+#include "rcsbase.h"
+
+static char *addjoin P((char*));
+static char const *getancestor P((char const*,char const*));
+static int buildjoin P((char const*));
+static int preparejoin P((char*));
+static int rmlock P((struct hshentry const*));
+static int rmworkfile P((void));
+static void cleanup P((void));
+
+static char const quietarg[] = "-q";
+
+static char const *expandarg, *suffixarg, *versionarg, *zonearg;
+static char const **joinlist; /* revisions to be joined */
+static int joinlength;
+static FILE *neworkptr;
+static int exitstatus;
+static int forceflag;
+static int lastjoin;			/* index of last element in joinlist  */
+static int lockflag; /* -1 -> unlock, 0 -> do nothing, 1 -> lock */
+static int mtimeflag;
+static struct hshentries *gendeltas;	/* deltas to be generated	*/
+static struct hshentry *targetdelta;	/* final delta to be generated	*/
+static struct stat workstat;
+
+mainProg(coId, "co", "$FreeBSD$")
+{
+	static char const cmdusage[] =
+		"\nco usage: co -{fIlMpqru}[rev] -ddate -jjoins -ksubst -sstate -T -w[who] -Vn -xsuff -zzone file ...";
+
+	char *a, *joinflag, **newargv;
+	char const *author, *date, *rev, *state;
+	char const *joinname, *newdate, *neworkname;
+	int changelock;  /* 1 if a lock has been changed, -1 if error */
+	int expmode, r, tostdout, workstatstat;
+	int Ttimeflag;
+	struct buf numericrev;	/* expanded revision number	*/
+	char finaldate[datesize];
+#	if OPEN_O_BINARY
+		int stdout_mode = 0;
+#	endif
+
+	setrid();
+	author = date = rev = state = 0;
+	joinflag = 0;
+	bufautobegin(&numericrev);
+	expmode = -1;
+	suffixes = X_DEFAULT;
+	tostdout = false;
+	Ttimeflag = false;
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	while (a = *++argv,  0<--argc && *a++=='-') {
+		switch (*a++) {
+
+                case 'r':
+		revno:
+			if (*a) {
+				if (rev) warn("redefinition of revision number");
+				rev = a;
+                        }
+                        break;
+
+		case 'f':
+			forceflag=true;
+			goto revno;
+
+                case 'l':
+			if (lockflag < 0) {
+				warn("-u overridden by -l.");
+                        }
+			lockflag = 1;
+                        goto revno;
+
+                case 'u':
+			if (0 < lockflag) {
+				warn("-l overridden by -u.");
+                        }
+			lockflag = -1;
+                        goto revno;
+
+                case 'p':
+			tostdout = true;
+                        goto revno;
+
+		case 'I':
+			interactiveflag = true;
+			goto revno;
+
+                case 'q':
+                        quietflag=true;
+                        goto revno;
+
+                case 'd':
+			if (date)
+				redefined('d');
+			str2date(a, finaldate);
+                        date=finaldate;
+                        break;
+
+                case 'j':
+			if (*a) {
+				if (joinflag) redefined('j');
+				joinflag = a;
+                        }
+                        break;
+
+		case 'M':
+			mtimeflag = true;
+			goto revno;
+
+                case 's':
+			if (*a) {
+				if (state) redefined('s');
+				state = a;
+                        }
+                        break;
+
+		case 'T':
+			if (*a)
+				goto unknown;
+			Ttimeflag = true;
+			break;
+
+                case 'w':
+			if (author) redefined('w');
+			if (*a)
+				author = a;
+			else
+				author = getcaller();
+                        break;
+
+		case 'x':
+			suffixarg = *argv;
+			suffixes = a;
+			break;
+
+		case 'V':
+			versionarg = *argv;
+			setRCSversion(versionarg);
+			break;
+
+		case 'z':
+			zonearg = *argv;
+			zone_set(a);
+			break;
+
+		case 'k':    /*  set keyword expand mode  */
+			expandarg = *argv;
+			if (0 <= expmode) redefined('k');
+			if (0 <= (expmode = str2expmode(a)))
+			    break;
+			/* fall into */
+                default:
+		unknown:
+			error("unknown option: %s%s", *argv, cmdusage);
+
+                };
+        } /* end of option processing */
+
+	/* Now handle all pathnames.  */
+	if (nerror) cleanup();
+	else if (argc < 1) faterror("no input file%s", cmdusage);
+	else for (;  0 < argc;  cleanup(), ++argv, --argc) {
+	ffree();
+
+	if (pairnames(argc, argv, lockflag?rcswriteopen:rcsreadopen, true, false)  <=  0)
+		continue;
+
+	/*
+	 * RCSname contains the name of the RCS file, and finptr
+	 * points at it.  workname contains the name of the working file.
+	 * Also, RCSstat has been set.
+         */
+	diagnose("%s  -->  %s\n", RCSname, tostdout?"standard output":workname);
+
+	workstatstat = -1;
+	if (tostdout) {
+#		if OPEN_O_BINARY
+		    int newmode = Expand==BINARY_EXPAND ? OPEN_O_BINARY : 0;
+		    if (stdout_mode != newmode) {
+			stdout_mode = newmode;
+			oflush();
+			VOID setmode(STDOUT_FILENO, newmode);
+		    }
+#		endif
+		neworkname = 0;
+		neworkptr = workstdout = stdout;
+	} else {
+		workstatstat = stat(workname, &workstat);
+		if (workstatstat == 0  &&  same_file(RCSstat, workstat, 0)) {
+			rcserror("RCS file is the same as working file %s.",
+				workname
+			);
+			continue;
+		}
+		neworkname = makedirtemp(1);
+		if (!(neworkptr = fopenSafer(neworkname, FOPEN_W_WORK))) {
+			if (errno == EACCES)
+			    workerror("permission denied on parent directory");
+			else
+			    eerror(neworkname);
+			continue;
+		}
+	}
+
+        gettree();  /* reads in the delta tree */
+
+	if (!Head) {
+                /* no revisions; create empty file */
+		diagnose("no revisions present; generating empty revision 0.0\n");
+		if (lockflag)
+			warn(
+				"no revisions, so nothing can be %slocked",
+				lockflag < 0 ? "un" : ""
+			);
+		Ozclose(&fcopy);
+		if (workstatstat == 0)
+			if (!rmworkfile()) continue;
+		changelock = 0;
+		newdate = 0;
+        } else {
+		int locks = lockflag ? findlock(false, &targetdelta) : 0;
+		if (rev) {
+                        /* expand symbolic revision number */
+			if (!expandsym(rev, &numericrev))
+                                continue;
+		} else {
+			switch (locks) {
+			    default:
+				continue;
+			    case 0:
+				bufscpy(&numericrev, Dbranch?Dbranch:"");
+				break;
+			    case 1:
+				bufscpy(&numericrev, targetdelta->num);
+				break;
+			}
+		}
+                /* get numbers of deltas to be generated */
+		if (!(targetdelta=genrevs(numericrev.string,date,author,state,&gendeltas)))
+                        continue;
+                /* check reservations */
+		changelock =
+			lockflag < 0 ?
+				rmlock(targetdelta)
+			: lockflag == 0 ?
+				0
+			:
+				addlock(targetdelta, true);
+
+		if (
+			changelock < 0
+			|| (changelock && !checkaccesslist())
+			|| dorewrite(lockflag, changelock) != 0
+		)
+			continue;
+
+		if (0 <= expmode)
+			Expand = expmode;
+		if (0 < lockflag  &&  Expand == VAL_EXPAND) {
+			rcserror("cannot combine -kv and -l");
+			continue;
+		}
+
+		if (joinflag && !preparejoin(joinflag))
+			continue;
+
+		diagnose("revision %s%s\n",targetdelta->num,
+			 0<lockflag ? " (locked)" :
+			 lockflag<0 ? " (unlocked)" : "");
+
+		/* Prepare to remove old working file if necessary.  */
+		if (workstatstat == 0)
+                        if (!rmworkfile()) continue;
+
+                /* skip description */
+                getdesc(false); /* don't echo*/
+
+		locker_expansion = 0 < lockflag;
+		targetdelta->name = namedrev(rev, targetdelta);
+		joinname = buildrevision(
+			gendeltas, targetdelta,
+			joinflag&&tostdout ? (FILE*)0 : neworkptr,
+			Expand < MIN_UNEXPAND
+		);
+#		if !large_memory
+			if (fcopy == neworkptr)
+				fcopy = 0;  /* Don't close it twice.  */
+#		endif
+		if_advise_access(changelock && gendeltas->first!=targetdelta,
+			finptr, MADV_SEQUENTIAL
+		);
+
+		if (donerewrite(changelock,
+			Ttimeflag ? RCSstat.st_mtime : (time_t)-1
+		) != 0)
+			continue;
+
+		if (changelock) {
+			locks += lockflag;
+			if (1 < locks)
+				rcswarn("You now have %d locks.", locks);
+		}
+
+		newdate = targetdelta->date;
+		if (joinflag) {
+			newdate = 0;
+			if (!joinname) {
+				aflush(neworkptr);
+				joinname = neworkname;
+			}
+			if (Expand == BINARY_EXPAND)
+				workerror("merging binary files");
+			if (!buildjoin(joinname))
+				continue;
+		}
+        }
+	if (!tostdout) {
+	    mode_t m = WORKMODE(RCSstat.st_mode,
+		!  (Expand==VAL_EXPAND  ||  (lockflag<=0 && StrictLocks))
+	    );
+	    time_t t = mtimeflag&&newdate ? date2time(newdate) : (time_t)-1;
+	    aflush(neworkptr);
+	    ignoreints();
+	    r = chnamemod(&neworkptr, neworkname, workname, 1, m, t);
+	    keepdirtemp(neworkname);
+	    restoreints();
+	    if (r != 0) {
+		eerror(workname);
+		error("see %s", neworkname);
+		continue;
+	    }
+	    diagnose("done\n");
+	}
+	}
+
+	tempunlink();
+	Ofclose(workstdout);
+	exitmain(exitstatus);
+
+}       /* end of main (co) */
+
+	static void
+cleanup()
+{
+	if (nerror) exitstatus = EXIT_FAILURE;
+	Izclose(&finptr);
+	ORCSclose();
+#	if !large_memory
+		if (fcopy!=workstdout) Ozclose(&fcopy);
+#	endif
+	if (neworkptr!=workstdout) Ozclose(&neworkptr);
+	dirtempunlink();
+}
+
+#if RCS_lint
+#	define exiterr coExit
+#endif
+	void
+exiterr()
+{
+	ORCSerror();
+	dirtempunlink();
+	tempunlink();
+	_exit(EXIT_FAILURE);
+}
+
+
+/*****************************************************************
+ * The following routines are auxiliary routines
+ *****************************************************************/
+
+	static int
+rmworkfile()
+/*
+ * Prepare to remove workname, if it exists, and if
+ * it is read-only.
+ * Otherwise (file writable):
+ *   if !quietmode asks the user whether to really delete it (default: fail);
+ *   otherwise failure.
+ * Returns true if permission is gotten.
+ */
+{
+	if (workstat.st_mode&(S_IWUSR|S_IWGRP|S_IWOTH) && !forceflag) {
+	    /* File is writable */
+	    if (!yesorno(false, "writable %s exists%s; remove it? [ny](n): ",
+			workname,
+			myself(workstat.st_uid) ? "" : ", and you do not own it"
+	    )) {
+		error(!quietflag && ttystdin()
+			? "checkout aborted"
+			: "writable %s exists; checkout aborted", workname);
+		return false;
+            }
+        }
+	/* Actual unlink is done later by caller. */
+	return true;
+}
+
+
+	static int
+rmlock(delta)
+	struct hshentry const *delta;
+/* Function: removes the lock held by caller on delta.
+ * Returns -1 if someone else holds the lock,
+ * 0 if there is no lock on delta,
+ * and 1 if a lock was found and removed.
+ */
+{       register struct rcslock * next, * trail;
+	char const *num;
+	struct rcslock dummy;
+        int whomatch, nummatch;
+
+        num=delta->num;
+        dummy.nextlock=next=Locks;
+        trail = &dummy;
+	while (next) {
+		whomatch = strcmp(getcaller(), next->login);
+                nummatch=strcmp(num,next->delta->num);
+                if ((whomatch==0) && (nummatch==0)) break;
+			/*found a lock on delta by caller*/
+                if ((whomatch!=0)&&(nummatch==0)) {
+                    rcserror("revision %s locked by %s; use co -r or rcs -u",
+			num, next->login
+		    );
+                    return -1;
+                }
+                trail=next;
+                next=next->nextlock;
+        }
+	if (next) {
+                /*found one; delete it */
+                trail->nextlock=next->nextlock;
+                Locks=dummy.nextlock;
+		next->delta->lockedby = 0;
+                return 1; /*success*/
+        } else  return 0; /*no lock on delta*/
+}
+
+
+
+
+/*****************************************************************
+ * The rest of the routines are for handling joins
+ *****************************************************************/
+
+
+	static char *
+addjoin(joinrev)
+	char *joinrev;
+/* Add joinrev's number to joinlist, yielding address of char past joinrev,
+ * or 0 if no such revision exists.
+ */
+{
+	register char *j;
+	register struct hshentry *d;
+	char terminator;
+	struct buf numrev;
+	struct hshentries *joindeltas;
+
+	j = joinrev;
+	for (;;) {
+	    switch (*j++) {
+		default:
+		    continue;
+		case 0:
+		case ' ': case '\t': case '\n':
+		case ':': case ',': case ';':
+		    break;
+	    }
+	    break;
+	}
+	terminator = *--j;
+	*j = 0;
+	bufautobegin(&numrev);
+	d = 0;
+	if (expandsym(joinrev, &numrev))
+	    d = genrevs(numrev.string,(char*)0,(char*)0,(char*)0,&joindeltas);
+	bufautoend(&numrev);
+	*j = terminator;
+	if (d) {
+		joinlist[++lastjoin] = d->num;
+		return j;
+	}
+	return 0;
+}
+
+	static int
+preparejoin(j)
+	register char *j;
+/* Parse join list J and place pointers to the
+ * revision numbers into joinlist.
+ */
+{
+        lastjoin= -1;
+        for (;;) {
+                while ((*j==' ')||(*j=='\t')||(*j==',')) j++;
+                if (*j=='\0') break;
+                if (lastjoin>=joinlength-2) {
+		    joinlist =
+			(joinlength *= 2) == 0
+			? tnalloc(char const *, joinlength = 16)
+			: trealloc(char const *, joinlist, joinlength);
+                }
+		if (!(j = addjoin(j))) return false;
+                while ((*j==' ') || (*j=='\t')) j++;
+                if (*j == ':') {
+                        j++;
+                        while((*j==' ') || (*j=='\t')) j++;
+                        if (*j!='\0') {
+				if (!(j = addjoin(j))) return false;
+                        } else {
+				rcsfaterror("join pair incomplete");
+                        }
+                } else {
+                        if (lastjoin==0) { /* first pair */
+                                /* common ancestor missing */
+                                joinlist[1]=joinlist[0];
+                                lastjoin=1;
+                                /*derive common ancestor*/
+				if (!(joinlist[0] = getancestor(targetdelta->num,joinlist[1])))
+                                       return false;
+                        } else {
+				rcsfaterror("join pair incomplete");
+                        }
+                }
+        }
+	if (lastjoin < 1)
+		rcsfaterror("empty join");
+	return true;
+}
+
+
+
+	static char const *
+getancestor(r1, r2)
+	char const *r1, *r2;
+/* Yield the common ancestor of r1 and r2 if successful, 0 otherwise.
+ * Work reliably only if r1 and r2 are not branch numbers.
+ */
+{
+	static struct buf t1, t2;
+
+	int l1, l2, l3;
+	char const *r;
+
+	l1 = countnumflds(r1);
+	l2 = countnumflds(r2);
+	if ((2<l1 || 2<l2)  &&  cmpnum(r1,r2)!=0) {
+	    /* not on main trunk or identical */
+	    l3 = 0;
+	    while (cmpnumfld(r1, r2, l3+1)==0 && cmpnumfld(r1, r2, l3+2)==0)
+		l3 += 2;
+	    /* This will terminate since r1 and r2 are not the same; see above. */
+	    if (l3==0) {
+		/* no common prefix; common ancestor on main trunk */
+		VOID partialno(&t1, r1, l1>2 ? 2 : l1);
+		VOID partialno(&t2, r2, l2>2 ? 2 : l2);
+		r = cmpnum(t1.string,t2.string)<0 ? t1.string : t2.string;
+		if (cmpnum(r,r1)!=0 && cmpnum(r,r2)!=0)
+			return r;
+	    } else if (cmpnumfld(r1, r2, l3+1)!=0)
+			return partialno(&t1,r1,l3);
+	}
+	rcserror("common ancestor of %s and %s undefined", r1, r2);
+	return 0;
+}
+
+
+
+	static int
+buildjoin(initialfile)
+	char const *initialfile;
+/* Function: merge pairs of elements in joinlist into initialfile
+ * If workstdout is set, copy result to stdout.
+ * All unlinking of initialfile, rev2, and rev3 should be done by tempunlink().
+ */
+{
+	struct buf commarg;
+	struct buf subs;
+	char const *rev2, *rev3;
+        int i;
+	char const *cov[10], *mergev[11];
+	char const **p;
+
+	bufautobegin(&commarg);
+	bufautobegin(&subs);
+	rev2 = maketemp(0);
+	rev3 = maketemp(3); /* buildrevision() may use 1 and 2 */
+
+	cov[1] = CO;
+	/* cov[2] setup below */
+	p = &cov[3];
+	if (expandarg) *p++ = expandarg;
+	if (suffixarg) *p++ = suffixarg;
+	if (versionarg) *p++ = versionarg;
+	if (zonearg) *p++ = zonearg;
+	*p++ = quietarg;
+	*p++ = RCSname;
+	*p = 0;
+
+	mergev[1] = MERGE;
+	mergev[2] = mergev[4] = "-L";
+	/* rest of mergev setup below */
+
+        i=0;
+        while (i<lastjoin) {
+                /*prepare marker for merge*/
+                if (i==0)
+			bufscpy(&subs, targetdelta->num);
+		else {
+			bufscat(&subs, ",");
+			bufscat(&subs, joinlist[i-2]);
+			bufscat(&subs, ":");
+			bufscat(&subs, joinlist[i-1]);
+		}
+		diagnose("revision %s\n",joinlist[i]);
+		bufscpy(&commarg, "-p");
+		bufscat(&commarg, joinlist[i]);
+		cov[2] = commarg.string;
+		if (runv(-1, rev2, cov))
+			goto badmerge;
+		diagnose("revision %s\n",joinlist[i+1]);
+		bufscpy(&commarg, "-p");
+		bufscat(&commarg, joinlist[i+1]);
+		cov[2] = commarg.string;
+		if (runv(-1, rev3, cov))
+			goto badmerge;
+		diagnose("merging...\n");
+		mergev[3] = subs.string;
+		mergev[5] = joinlist[i+1];
+		p = &mergev[6];
+		if (quietflag) *p++ = quietarg;
+		if (lastjoin<=i+2 && workstdout) *p++ = "-p";
+		*p++ = initialfile;
+		*p++ = rev2;
+		*p++ = rev3;
+		*p = 0;
+		switch (runv(-1, (char*)0, mergev)) {
+		    case DIFF_FAILURE: case DIFF_SUCCESS:
+			break;
+		    default:
+			goto badmerge;
+		}
+                i=i+2;
+        }
+	bufautoend(&commarg);
+	bufautoend(&subs);
+        return true;
+
+    badmerge:
+	nerror++;
+	bufautoend(&commarg);
+	bufautoend(&subs);
+	return false;
+}
diff --git a/gnu/usr.bin/rcs/doc/rcs.ms b/gnu/usr.bin/rcs/doc/rcs.ms
new file mode 100644
index 0000000000000..f6b0db300330e
--- /dev/null
+++ b/gnu/usr.bin/rcs/doc/rcs.ms
@@ -0,0 +1,1518 @@
+.\" Format this file with:
+.\" pic file | tbl | troff -ms
+.\"
+.\" \*s stands for $, and avoids problems when this file is checked in.
+.ds s $
+.de D(
+.DS
+.nr VS 12p
+.vs 12p
+.I
+..
+.de D)
+.DE
+.nr VS 18p
+.vs 18p
+.R
+..
+.de Id
+.ND \\$4
+..
+.Id $FreeBSD$
+.RP
+.TL
+RCS\*-A System for Version Control
+.sp
+.AU
+Walter F. Tichy
+.AI
+Department of Computer Sciences
+Purdue University
+West Lafayette, Indiana 47907
+.sp
+.AB
+An important problem in program development and maintenance is version control,
+i.e., the task of keeping a software system consisting of many versions and
+configurations well organized.
+The Revision Control System (RCS)
+is a software tool that assists with that task.
+RCS manages revisions of text documents, in particular source programs,
+documentation, and test data.
+It automates the storing, retrieval, logging and identification of revisions,
+and it provides selection mechanisms for composing configurations.
+This paper introduces basic version control concepts and
+discusses the practice of version control
+using RCS.
+For conserving space, RCS stores deltas, i.e., differences between
+successive revisions.  Several delta storage methods are discussed.
+Usage statistics show that RCS's delta storage method is
+space and time efficient.
+The paper concludes with a detailed survey of version control tools.
+.sp
+\fBKeywords\fR: configuration management, history management,
+version control, revisions, deltas.
+.AE
+.FS
+An earlier version of this paper was published in
+.I "Software\*-Practice & Experience"
+.B 15 ,
+7 (July 1985), 637-654.
+.FE
+.nr VS 18p
+.LP
+.NH
+Introduction
+.PP
+Version control is the task of keeping software
+systems consisting of many versions and configurations well organized.
+The Revision Control System (RCS) is a set of UNIX
+commands that assist with that task.
+.PP
+RCS' primary function is to manage \fIrevision groups\fR.
+A revision group is a set of text documents, called \fIrevisions\fR,
+that evolved from each other.  A new revision is
+created by manually editing an existing one.
+RCS organizes the revisions into an ancestral tree.  The initial revision
+is the root of the tree, and the tree edges indicate
+from which revision a given one evolved.
+Besides managing individual revision groups, RCS provides
+flexible selection functions for composing configurations.
+RCS may be combined with MAKE\u1\d,
+resulting in a powerful package for version control.
+.PP
+RCS also offers facilities for
+merging updates with customer modifications,
+for distributed software development, and
+for automatic identification.
+Identification is the `stamping'
+of revisions and configurations with unique markers.
+These markers are akin to serial numbers,
+telling software maintainers unambiguously which configuration
+is before them.
+.PP
+RCS is designed for both production and experimental
+environments.
+In production environments,
+access controls detect update conflicts and prevent overlapping changes.
+In experimental environments, where strong controls are
+counterproductive, it is possible to loosen the controls.
+.PP
+Although RCS was originally intended for programs, it is useful for any
+text that is revised frequently and whose previous revisions must be
+preserved.  RCS has been applied successfully to store the source
+text for drawings, VLSI layouts, documentation, specifications,
+test data, form letters and articles.
+.PP
+This paper discusses the practice of
+version control using RCS.
+It also introduces basic version control concepts,
+useful for clarifying current practice and designing similar systems.
+Revision groups of individual components are treated in the next three sections,
+and the extensions to configurations follow.
+Because of its size, a survey of version control tools
+appears at the end of the paper.
+.NH
+Getting started with RCS
+.PP
+Suppose a text file \fIf.c\fR is to be placed under control of RCS.
+Invoking the check-in command
+.D(
+ci  f.c
+.D)
+creates a new revision group with the contents of
+\fIf.c\fR as the initial
+revision (numbered 1.1)
+and stores the group into the file \fIf.c,v\fR.
+Unless told otherwise, the command deletes \fIf.c\fR.
+It also asks for a description of the group.
+The description should state the common purpose of all revisions in the group,
+and becomes part of the group's documentation.
+All later check-in commands will ask for a log entry,
+which should summarize the changes made.
+(The first revision is assigned a default log message,
+which just records the fact that it is the initial revision.)
+.PP
+Files ending in \fI,v\fR
+are called \fIRCS files\fR (\fIv\fR stands for \fIv\fRersions);
+the others are called working files.
+To get back the working file \fIf.c\fR in the previous example,
+execute the check-out command:
+.D(
+co  f.c
+.D)
+.R
+This command extracts the latest revision from
+the revision group \fIf.c,v\fR and writes
+it into \fIf.c\fR.
+The file \fIf.c\fR can now be edited and, when finished,
+checked back in with \fIci\fR:
+.D(
+ci  f.c
+.D)
+\fICi\fR assigns number 1.2 to
+the new revision.
+If \fIci\fR complains with the message
+.D(
+ci error: no lock set by <login>
+.D)
+then the system administrator has decided to configure RCS for a
+production environment by enabling the `strict locking feature'.
+If this feature is enabled, all RCS files are initialized
+such that check-in operations require a lock on the previous revision
+(the one from which the current one evolved).
+Locking prevents overlapping modifications if several people work on the same file.
+If locking is required, the revision should
+have been locked during the check-out by using
+the option \fI\-l\fR:
+.D(
+co  \-l  f.c
+.D)
+Of course it is too late now for the check-out with locking, because
+\fIf.c\fR has already been changed; checking out the file again
+would overwrite the modifications.
+(To prevent accidental overwrites, \fIco\fR senses the presence
+of a working file and asks whether the user really intended to overwrite it.
+The overwriting check-out is sometimes useful for
+backing up to the previous revision.)
+To be able to proceed with the check-in in the present case, first execute
+.D(
+rcs  \-l  f.c
+.D)
+This command retroactively locks the latest revision, unless someone
+else locked it in the meantime.  In this case, the two programmers
+involved have to negotiate whose
+modifications should take precedence.
+.PP
+If an RCS file is private, i.e., if only the owner of the file is expected
+to deposit revisions into it, the strict locking feature is unnecessary and
+may be disabled.
+If strict locking is disabled,
+the owner of the RCS file need not have a lock for check-in.
+For safety reasons, all others
+still do.  Turning strict locking off and on is done with the commands:
+.D(
+rcs  \-U  f.c       \fRand\fP         rcs  \-L  f.c
+.D)
+These commands enable or disable the strict locking feature for each RCS file
+individually.
+The system administrator only decides whether strict locking is
+enabled initially.
+.PP
+To reduce the clutter in a working directory, all RCS files can be moved
+to a subdirectory with the name \fIRCS\fR.
+RCS commands look first into that directory for RCS files.
+All the commands presented above work
+with the \fIRCS\fR subdirectory without change.\(dg
+.FS \(dg
+Pairs of RCS and working files can actually be specified in 3 ways:
+a) both are given, b) only the working file is given, c) only the
+RCS file is given.
+If a pair is given, both files may have arbitrary path prefixes;
+RCS commands pair them up intelligently.
+.FE
+.PP
+It may be undesirable that \fIci\fR deletes the working file.
+For instance, sometimes one would like to save the current revision,
+but continue editing.
+Invoking
+.D(
+ci  \-l  f.c
+.D)
+checks in \fIf.c\fR as usual, but performs an additional
+check-out with locking afterwards.  Thus, the working file does
+not disappear after the check-in.
+Similarly, the option
+\fI\-u\fR does a check-in followed by a check-out without
+locking.  This option is useful if the file is needed for compilation after the check-in.
+Both options update the identification markers in the working file
+(see below).
+.PP
+Besides the operations \fIci\fR and \fIco\fR, RCS provides the following
+commands:
+.sp 0
+.nr VS 12p
+.vs 12p
+.TS
+tab(%);
+li l.
+ident%extract identification markers
+rcs%change RCS file attributes
+rcsclean%remove unchanged working files (optional)
+rcsdiff%compare revisions
+rcsfreeze%record a configuration (optional)
+rcsmerge%merge revisions
+rlog%read log messages and other information in RCS files
+.TE
+A synopsis of these commands appears in the Appendix.
+.NH 2
+Automatic Identification
+.PP
+RCS can stamp source and object code with special identification strings,
+similar to product and serial numbers.
+To obtain such identification, place the marker
+.D(
+\*sId\*s
+.D)
+into the text of a revision, for instance inside a comment.
+The check-out operation will replace this marker with a string of the form
+.D(
+\*sId:  filename  revisionnumber  date  time  author  state  locker \*s
+.D)
+This string need never be touched, because \fIco\fR keeps it
+up to date automatically.
+To propagate the marker into object code, simply put
+it into a literal character string.  In C, this is done as follows:
+.D(
+static char rcsid[] = \&"\*sId\*s\&";
+.D)
+The command \fIident\fR extracts such markers from any file, in particular from
+object code.
+\fIIdent\fR helps to find out
+which revisions of which modules were used in a given program.
+It returns a complete and unambiguous component list,
+from which a copy of the program can be reconstructed.
+This facility is invaluable for program maintenance.
+.PP
+There are several additional identification markers, one for each component
+of \*sId\*s.
+The marker
+.D(
+\*sLog\*s
+.D)
+has a similar function.  It accumulates
+the log messages that are requested during check-in.
+Thus, one can maintain the complete history of a revision directly inside it,
+by enclosing it in a comment.
+Figure 1 is an edited version of a log contained in revision 4.1 of
+the file \fIci.c\fR.  The log appears at the beginning of the file,
+and makes it easy to determine what the recent modifications were.
+.sp
+.nr VS 12p
+.vs 12p
+.ne 18
+.nf
+.in +0.5i
+/*
+.in +\w'/'u
+* \*sLog: ci.c,v \*s
+* Revision 4.1  1983/05/10 17:03:06  wft
+* Added option \-d and \-w, and updated assignment of date, etc. to new delta.
+* Added handling of default branches.
+*
+* Revision 3.9  1983/02/15 15:25:44  wft
+* Added call to fastcopy() to copy remainder of RCS file.
+*
+* Revision 3.8  1983/01/14 15:34:05  wft
+* Added ignoring of interrupts while new RCS file is renamed;
+* avoids deletion of RCS files by interrupts.
+*
+* Revision 3.7  1982/12/10 16:09:20  wft
+* Corrected checking of return code from diff.
+* An RCS file now inherits its mode during the first ci from the working file,
+* except that write permission is removed.
+*/
+.in 0
+.ce 1
+Figure 1.  Log entries produced by the marker \*sLog\*s.
+.fi
+.nr VS 18p
+.vs 18p
+.sp 0
+.LP
+Since revisions are stored in the form of differences,
+each log message is
+physically stored once,
+independent of the number of revisions present.
+Thus, the \*sLog\*s marker incurs negligible space overhead.
+.NH
+The RCS Revision Tree
+.PP
+RCS arranges revisions in an ancestral tree.
+The \fIci\fR command builds this tree; the auxiliary command \fIrcs\fR
+prunes it.
+The tree has a root revision, normally numbered 1.1, and successive revisions
+are numbered 1.2, 1.3, etc.  The first field of a revision number
+is called the \fIrelease number\fR and the second one
+the \fIlevel number\fR.  Unless given explicitly,
+the \fIci\fR command assigns a new revision number
+by incrementing the level number of the previous revision.
+The release number must be incremented explicitly, using the
+\fI\-r\fR option of \fIci\fR.
+Assuming there are revisions 1.1, 1.2, and 1.3 in the RCS file f.c,v, the command
+.D(
+ci  \-r2.1  f.c       \fRor\fP       ci  \-r2  f.c
+.D)
+assigns the number 2.1 to the new revision.
+Later check-ins without the \fI\-r\fR option will assign the numbers 2.2, 2.3,
+and so on.
+The release number should be incremented only at major transition points
+in the development, for instance when a new release of a software product has
+been completed.
+.NH 2
+When are branches needed?
+.PP
+A young revision tree is slender:
+It consists of only one branch, called the trunk.
+As the tree ages, side branches may form.
+Branches are needed in the following 4 situations.
+.IP "\fITemporary fixes\fR"
+.sp 0
+Suppose a tree has 5 revisions grouped in 2 releases,
+as illustrated in Figure 2.
+Revision 1.3, the last one of release 1, is in operation at customer sites,
+while release 2 is in active development.
+.ne 4
+.PS 4i
+.ps -2
+box "1.1"
+arrow
+box "1.2"
+arrow
+box "1.3"
+arrow
+box "2.1"
+arrow
+box "2.2"
+arrow dashed
+.ps +2
+.PE
+.ce 1
+Figure 2.  A slender revision tree.
+.sp 0
+Now imagine a customer requesting a fix of
+a problem in revision 1.3, although actual development has moved on
+to release 2.  RCS does not permit an extra
+revision to be spliced in between 1.3 and 2.1, since that would not reflect
+the actual development history.  Instead, create a branch
+at revision 1.3, and check in the fix on that branch.
+The first branch starting at 1.3 has number 1.3.1, and
+the revisions on that branch are numbered 1.3.1.1, 1.3.1.2, etc.
+The double numbering is needed to allow for another
+branch at 1.3, say 1.3.2.
+Revisions on the second branch would be numbered
+1.3.2.1, 1.3.2.2, and so on.
+The following steps create
+branch 1.3.1 and add revision 1.3.1.1:
+.sp 0
+.I
+.nr VS 12p
+.vs 12p
+.TS
+tab(%);
+l l l.
+     %co  \-r1.3  f.c% \*- check out revision 1.3
+     %edit  f.c% \*- change it
+     %ci  \-r1.3.1  f.c% \*- check it in on branch 1.3.1
+.TE
+.nr VS 18p
+.vs 18p
+.R
+This sequence of commands transforms the tree of Figure 2 into
+the one in Figure 3.
+Note that it may be necessary to incorporate the differences
+between 1.3 and 1.3.1.1
+into a revision at level 2.  The operation \fIrcsmerge\fR automates this
+process (see the Appendix).
+.ne 7
+.PS 4i
+.ps -2
+     box "1.1"
+     arrow
+     box "1.2"
+     arrow
+R13: box "1.3"
+     arrow
+R21: box "2.1"
+     arrow
+R22: box "2.2"
+     arrow dashed
+     line invis down from R21.s
+RB1: box "1.3.1.1"
+     arrow dashed right from RB1.e
+     arrow from R13.s to RB1.w
+.ps +2
+.PE
+.ce 1
+Figure 3.  A revision tree with one side branch
+.sp
+.IP "\fIDistributed development and customer modifications\fR"
+.sp 0
+Assume a situation as in Figure 2, where revision 1.3 is in operation
+at several customer sites,
+while release 2 is in development.
+Customer sites should use RCS to store the distributed software.
+However, customer modifications should not be placed on the same branch
+as the distributed source; instead, they should be placed on a side branch.
+When the next software distribution arrives,
+it should be appended to the trunk of
+the customer's RCS file, and the customer
+can then merge the local modifications back into the new release.
+In the above example, a
+customer's RCS file would contain the following tree, assuming
+that the customer has received revision 1.3, added his local modifications
+as revision 1.3.1.1, then received revision 2.4, and merged
+2.4 and 1.3.1.1, resulting in 2.4.1.1.
+.ne 7
+.PS 4i
+.ps -2
+R13: box "1.3"
+     line invis
+R21: box invis
+     line invis
+R22: box invis
+     line invis
+R24: box "2.4"
+     line invis
+R25: box invis
+     line invis
+     arrow from R13.e to R24.w
+     line invis down from R21.s
+RB1: box "1.3.1.1"
+     arrow from R13.s to RB1.w
+     right
+     line invis down from R25.s
+RB2: box "2.4.1.1"
+     arrow from R24.s to RB2.w
+.ps +2
+.PE
+.ce 1
+Figure 4.  A customer's revision tree with local modifications.
+.sp 1
+This approach is actually practiced in the CSNET project,
+where several universities and a company cooperate
+in developing a national computer network.
+.IP "\fIParallel development\fR"
+.sp 0
+Sometimes it is desirable to explore an alternate design or
+a different implementation technique in parallel with the
+main line development.  Such development
+should be carried out on a side branch.
+The experimental changes may later be moved into the main line, or abandoned.
+.IP "\fIConflicting updates\fR"
+.sp 0
+A common occurrence is that one programmer
+has checked out a revision, but cannot complete the assignment
+for some reason.  In the meantime, another person
+must perform another modification
+immediately.  In that case, the second person should check-out the same revision,
+modify it, and check it in on a side branch, for later merging.
+.PP
+Every node in a revision tree consists of the following attributes:
+a revision number, a check-in date and time, the author's identification,
+a log entry, a state and the actual text.  All these attributes
+are determined at the time the revision is checked in.
+The state attribute indicates the status of a revision.
+It is set automatically to `experimental' during check-in.
+A revision can later be promoted to a higher status, for example
+`stable' or `released'.  The set of states is user-defined.
+.NH 2
+Revisions are represented as deltas
+.PP
+For conserving space, RCS stores revisions in the form
+of deltas, i.e., as differences between revisions.
+The user interface completely hides this fact.
+.PP
+A delta is a sequence of edit commands that transforms one string
+into another.  The deltas employed by RCS are line-based, which means
+that the only edit commands allowed are insertion and deletion of lines.
+If a single character in a line is changed, the
+edit scripts consider the entire line changed.
+The program \fIdiff\fR\u2\d
+produces a small, line-based delta between pairs of text files.
+A character-based edit script would take much longer to compute,
+and would not be significantly shorter.
+.PP
+Using deltas is a classical space-time tradeoff: deltas reduce the
+space consumed, but increase access time.
+However, a version control tool should impose as little delay
+as possible on programmers.
+Excessive delays discourage the use of version controls,
+or induce programmers to take shortcuts that compromise system integrity.
+To gain reasonably fast access time for both editing and compiling,
+RCS arranges deltas in the following way.
+The most recent revision on the trunk is stored intact.
+All other revisions on the trunk are stored as reverse deltas.
+A reverse delta describes how to go backward in the development history:
+it produces the desired revision if applied to the successor of that revision.
+This implementation has the advantage
+that extraction of the latest revision is a simple and fast copy
+operation.
+Adding a new revision to the trunk is also fast: \fIci\fR simply
+adds the new revision intact, replaces the previous
+revision with a reverse delta, and keeps the rest of the old deltas.
+Thus, \fIci\fR requires the computation
+of only one new delta.
+.PP
+Branches need special treatment.  The naive solution would be to
+store complete copies for the tips of all branches.
+Clearly, this approach would cost too much space.  Instead,
+RCS uses \fIforward\fR deltas for branches.  Regenerating a revision
+on a side branch proceeds as follows.  First, extract the latest revision
+on the trunk; secondly, apply reverse deltas until the fork revision for
+the branch is obtained; thirdly, apply forward deltas until the desired
+branch revision is reached.  Figure 5 illustrates a tree with
+one side branch.  Triangles pointing to the left and right represent
+reverse and forward deltas, respectively.
+.ne 8
+.PS 4i
+.ps -2
+define BD X [line invis $1 right .5;
+line up .3 then left .5 down .3 then right .5 down .3 then up .3] X
+
+define FD X [line invis $1 right .5;
+line left .5 down .3 then up .6 then right .5 down .3;] X
+
+right
+D11:	BD(" 1.1")
+	arrow right from D11.e
+D12:	BD(" 1.2")
+	arrow right from D12.e
+D13:	BD(" 1.3")
+	arrow right from D13.e
+D21:	BD(" 2.1")
+	arrow right from D21.e
+D22:	box "2.2"
+	line invis down from D21.s
+F1:	FD("1.3.1.1 ")
+	arrow from D13.se to F1.w
+	arrow from F1.e right
+	right
+F2:	FD("1.3.1.2 ")
+.ps +2
+.PE
+.ce 1
+Figure 5.  A revision tree with reverse and forward deltas.
+.sp 0
+.PP
+Although implementing fast check-out for the latest trunk revision,
+this arrangement has the disadvantage that generation of other revisions
+takes time proportional to the number of deltas applied.  For example,
+regenerating the branch tip in Figure 5 requires application of five
+deltas (including the initial one).  Since usage statistics show that
+the latest trunk revision is the one that is retrieved in 95 per cent
+of all cases (see the section on usage statistics), biasing check-out time
+in favor of that revision results in significant savings.
+However, careful implementation of the delta application process is
+necessary to provide low retrieval overhead for other revisions, in
+particular for branch tips.
+.PP
+There are several techniques for delta application.
+The naive one is to pass each delta to a general-purpose text editor.
+A prototype of RCS invoked the UNIX editor \fIed\fR both
+for applying deltas and for expanding the identification markers.
+Although easy to implement, performance was poor, owing to the
+high start-up costs and excess generality of \fIed\fR.  An intermediate
+version of RCS used a special-purpose, stream-oriented editor.
+This technique reduced the cost of applying a delta to the cost of
+checking out the latest trunk revision.  The reason for this behavior
+is that each delta application involves a complete pass over
+the preceding revision.
+.PP
+However, there is a much better algorithm.  Note that the deltas are
+line oriented and that most of the work of a stream editor involves
+copying unchanged lines from one revision to the next.  A faster
+algorithm avoids unnecessary copying of character strings by using
+a \fIpiece table\fR.
+A piece table is a one-dimensional array, specifying how a given
+revision is `pieced together' from lines in the RCS file.
+Suppose piece table \fIPT\dr\u\fR represents revision \fIr\fR.
+Then \fIPT\dr\u[i]\fR contains the starting position of line \fIi\fR
+of revision \fIr\fR.
+Application of the next delta transforms piece table \fIPT\dr\u\fR
+into \fIPT\dr+1\u\fR.  For instance, a delete command removes a
+series of entries from the piece table.  An insertion command inserts
+new entries, moving the entries following the insertion point further down the
+array.  The inserted entries point to the text lines in the delta.
+Thus, no I/O is involved except for reading the delta itself.  When all
+deltas have been applied to the piece table, a sequential pass
+through the table looks up each line in the RCS file and copies it to
+the output file, updating identification markers at the same time.
+Of course, the RCS file must permit random access, since the copied
+lines are scattered throughout that file.  Figure 6 illustrates an
+RCS file with two revisions and the corresponding piece tables.
+.ne 13
+.sp 6
+.ce 1
+\fIFigure 6 is not available.\fP
+.sp 5
+.ce 1
+Figure 6.  An RCS file and its piece tables
+.sp 0
+.PP
+The piece table approach has the property that the time for applying a single
+delta is roughly determined by the size of the delta, and not by the
+size of the revision.  For example, if a delta is
+10 per cent of the size of a revision, then applying it takes only
+10 per cent of the time to generate the latest trunk revision.  (The stream
+editor would take 100 per cent.)
+.PP
+There is an important alternative for representing deltas that affects
+performance.  SCCS\u3\d,
+a precursor of RCS, uses \fIinterleaved\fR deltas.
+A file containing interleaved deltas is partitioned into blocks of lines.
+Each block has a header that specifies to which revision(s) the block
+belongs.  The blocks are sorted out in such a way that a single
+pass over the file can pick up all the lines belonging to a given
+revision.  Thus, the regeneration time for all revisions is the same:
+all headers must be inspected, and the associated blocks either copied
+or skipped.  As the number of revisions increases, the cost of retrieving
+any revision is much higher than the cost of checking out the
+latest trunk revision with reverse deltas.  A detailed comparison
+of SCCS's interleaved deltas and RCS's reverse deltas can be found
+in Reference 4.
+This reference considers the version of RCS with the
+stream editor only.  The piece table method improves performance
+further, so that RCS is always faster than SCCS, except if 10
+or more deltas are applied.
+.PP
+Additional speed-up for both delta methods can be obtained by caching
+the most recently generated revision, as has been implemented in DSEE.\u5\d
+With caching, access time to frequently used revisions can approach normal file
+access time, at the cost of some additional space.
+.NH
+Locking: A Controversial Issue
+.PP
+The locking mechanism for RCS was difficult to design.
+The problem and its solution are first presented in their `pure' form,
+followed by a discussion of the complications
+caused by `real-world' considerations.
+.PP
+RCS must prevent two or more persons from depositing competing changes of the
+same revision.
+Suppose two programmers check out revision 2.4 and
+modify it.  Programmer A checks in a revision before programmer B\&.
+Unfortunately, programmer B has not seen A's
+changes, so the effect is that A's changes are covered up by B's deposit.
+A's changes are not lost since all revisions
+are saved, but they are confined to a single revision.\(dd
+.FS \(dd
+Note that this problem is entirely different from the atomicity problem.
+Atomicity means that
+concurrent update operations on the same RCS file cannot be permitted,
+because that may result in inconsistent data.
+Atomic updates are essential (and implemented in RCS),
+but do not solve the conflict discussed here.
+.FE
+.PP
+This conflict is prevented in RCS by locking.
+Whenever someone intends to edit a revision (as opposed
+to reading or compiling it), the revision should be checked out
+and locked,
+using the \fI\-l\fR option on \fIco\fR.  On subsequent check-in,
+\fIci\fR tests the lock and then removes it.
+At most one programmer at a time may
+lock a particular revision, and only this programmer may check in
+the succeeding revision.
+Thus, while a revision is locked, it is the exclusive responsibility
+of the locker.
+.PP
+An important maxim for software tools like RCS is that they must
+not stand in the way of making progress with a project.
+This consideration leads to several weakenings of the locking mechanism.
+First of all, even if a revision is locked, it can
+still be checked out.  This is necessary if other people
+wish to compile or inspect the locked revision
+while the next one is in preparation.  The only operations they
+cannot do are to lock the revision or to check in the succeeding one.  Secondly,
+check-in operations on other branches in the RCS file are still possible; the
+locking of one revision does not affect any other revision.
+Thirdly, revisions are occasionally locked for a long period of time
+because a programmer is absent or otherwise unable to complete
+the assignment.  If another programmer has to make a pressing change,
+there are the following three alternatives for making progress:
+a) find out who is holding the lock and ask that person to release it;
+b) check out the locked revision, modify it, check it
+in on a branch, and merge the changes later;
+c) break the lock.  Breaking a lock leaves a highly visible
+trace, namely an electronic mail message that is sent automatically to the
+holder of the lock, recording the breaker and a commentary requested from him.
+Thus, breaking locks is tolerated under certain circumstances,
+but will not go unnoticed.
+Experience has shown that the automatic mail message attaches a high enough
+stigma to lock breaking,
+such that programmers break locks only in real emergencies,
+or when a co-worker resigns and leaves locked revisions behind.
+.PP
+If an RCS file is private, i.e., when a programmer owns an RCS file
+and does not expect anyone else to perform check-in operations,
+locking is an unnecessary nuisance.
+In this case,
+the `strict locking feature' discussed earlier may be disabled,
+provided that file protection
+is set such that only the owner may write the RCS file.
+This has the effect that only the owner can check-in revisions,
+and that no lock is needed for doing so.
+.PP
+As added protection,
+each RCS file contains an access list that specifies the users
+who may execute update operations.  If an access list is empty,
+only normal UNIX file protection applies.  Thus, the access list is
+useful for restricting the set of people who would otherwise have update
+permission.  Just as with locking, the access list
+has no effect on read-only operations such as \fIco\fR.  This approach
+is consistent with the UNIX philosophy of openness, which contributes
+to a productive software development environment.
+.NH
+Configuration Management
+.PP
+The preceding sections described how RCS deals with revisions of individual
+components; this section discusses how to handle configurations.
+A configuration is a set of revisions, where each revision comes
+from a different revision group, and the revisions are selected
+according to a certain criterion.
+For example,
+in order to build a functioning compiler, the `right'
+revisions from the scanner, the parser, the optimizer
+and the code generator must be combined.
+RCS, in conjunction with MAKE,
+provides a number of facilities to effect a smooth selection.
+.NH 2
+RCS Selection Functions
+.PP
+.IP "\fIDefault selection\fR"
+.sp 0
+During development, the usual selection criterion is to choose
+the latest revision of all components.  The \fIco\fR command
+makes this selection by default.  For example, the command
+.D(
+co  *,v
+.D)
+retrieves the latest revision on the default branch of each RCS file
+in the current directory.
+The default branch is usually the trunk, but may be
+set to be a side branch.
+Side branches as defaults are needed in distributed software development,
+as discussed in the section on the RCS revision tree.
+.sp
+.IP "\fIRelease based selection\fR"
+.sp 0
+Specifying a release or branch number selects the latest revision in
+that release or branch.
+For instance,
+.D(
+co  \-r2  *,v
+.D)
+retrieves the latest revision with release number 2 from each RCS file.
+This selection is convenient if a release has been completed and
+development has moved on to the next release.
+.sp
+.IP "\fIState and author based selection\fR"
+.sp 0
+If the highest level number within a given release number
+is not the desired one,
+the state attribute can help.  For example,
+.D(
+co  \-r2  \-sReleased  *,v
+.D)
+retrieves the latest revision with release number 2 whose state attribute
+is `Released'.
+Of course, the state attribute has to be set appropriately, using the
+\fIci\fR or \fIrcs\fR commands.
+Another alternative is to select a revision by its author,
+using the \fI\-w\fR option.
+.sp
+.IP "\fIDate based selection\fR"
+.sp 0
+Revisions may also be selected by date.
+Suppose a release of an entire system was
+completed and current on March 4, at 1:00 p.m. local time.  Then the command
+.D(
+co  \-d'March 4, 1:00 pm LT'  *,v
+.D)
+checks out all the components of that release, independent of the numbering.
+The \fI\-d\fR option specifies a `cutoff date', i.e.,
+the revision selected has a check-in date that
+is closest to, but not after the date given.
+.IP "\fIName based selection\fR"
+.sp 0
+The most powerful selection function is based on assigning symbolic
+names to revisions and branches.
+In large systems, a single release number or date is not sufficient
+to collect the appropriate revisions from all groups.
+For example, suppose one wishes to combine release 2
+of one subsystem and release 15 of another.
+Most likely, the creation dates of those releases differ also.
+Thus, a single revision number or date passed to the \fIco\fR command
+will not suffice to select the right revisions.
+Symbolic revision numbers solve this problem.
+Each RCS file may contain a set of symbolic names that are mapped
+to numeric revision numbers.  For example, assume
+the symbol \fIV3\fR is bound to release number 2 in file \fIs,v\fR, and to
+revision number 15.9 in \fIt,v\fR.
+Then the single command
+.D(
+co  \-rV3  s,v  t,v
+.D)
+retrieves the latest revision of release 2 from \fIs,v\fR,
+and revision 15.9 from \fIt,v\fR.
+In a large system with many modules, checking out all
+revisions with one command greatly simplifies configuration management.
+.PP
+Judicious use of symbolic revision numbers helps with organizing
+large configurations.
+A special command, \fIrcsfreeze\fR,
+assigns a symbolic revision number to a selected revision
+in every RCS file.
+\fIRcsfreeze\fR effectively freezes a configuration.
+The assigned symbolic revision number selects all components
+of the configuration.
+If necessary, symbolic numbers
+may even be intermixed with numeric ones.  Thus, \fIV3.5\fR in the
+above example
+would select revision 2.5 in \fIs,v\fR and branch 15.9.5 in \fIt,v\fR.
+.PP
+The options \fI\-r\fR, \fI\-s\fR, \fI\-w\fR and \fI\-d\fR
+may be combined.  If a branch is given, the latest revision
+on that branch satisfying all conditions is retrieved;
+otherwise, the default branch is used.
+.NH 2
+Combining MAKE and RCS
+.PP
+MAKE\u1\d
+is a program that processes configurations.
+It is driven by configuration specifications
+recorded in a special file, called a `Makefile'.
+MAKE avoids redundant processing steps
+by comparing creation dates of source and processed objects.
+For example, when instructed to compile all
+modules of a given system, it only recompiles
+those source modules that were changed
+since they were processed last.
+.PP
+MAKE has been extended with an auto-checkout feature for RCS.*
+.FS *
+This auto-checkout extension is available only in some versions of MAKE,
+e.g. GNU MAKE.
+.FE
+When a certain file to be processed is not present,
+MAKE attempts a check-out operation.
+If successful, MAKE performs the required processing, and then deletes
+the checked out file to conserve space.
+The selection parameters discussed above can be passed to MAKE
+either as parameters, or directly embedded in the Makefile.
+MAKE has also been extended to search the subdirectory named \fIRCS\fR
+for needed files, rather than just the current working directory.
+However, if a working file is present, MAKE totally ignores the corresponding
+RCS file and uses the working file.
+(In newer versions of MAKE distributed by AT&T and others,
+auto-checkout can be
+achieved with the rule DEFAULT, instead of a special extension of MAKE.
+However, a file checked out by the rule DEFAULT
+will not be deleted after processing. \fIRcsclean\fR can be
+used for that purpose.)
+.PP
+With auto-checkout, RCS/MAKE can effect a selection rule
+especially tuned for multi-person software development and maintenance.
+In these situations,
+programmers should obtain configurations that consist of
+the revisions they have personally checked out plus the latest
+checked in revision of all other revision groups.
+This schema can be set up as follows.
+.PP
+Each programmer chooses a working directory
+and places into it a symbolic link, named \fIRCS\fR,
+to the directory containing the relevant RCS files.
+The symbolic link makes sure that \fIco\fR and \fIci\fR
+operations need only specify the working files, and that
+the Makefile need not be changed.
+The programmer then checks out the needed files and modifies them.
+If MAKE is invoked,
+it composes configurations by selecting those
+revisions that are checked out, and the rest from the
+subdirectory \fIRCS\fR.
+The latter selection may be controlled by a symbolic
+revision number or any of the other selection criteria.
+If there are several programmers editing in separate working directories,
+they are insulated from each other's changes until checking in their
+modifications.
+.PP
+Similarly, a maintainer can recreate an older configuration
+by starting to work in an empty working directory.
+During the initial MAKE invocation, all revisions are selected from RCS files.
+As the maintainer checks out files and modifies them,
+a new configuration is gradually built up.
+Every time MAKE is invoked, it substitutes the modified revisions
+into the configuration being manipulated.
+.PP
+A final application of RCS is to use it for storing Makefiles.
+Revision groups of Makefiles represent
+multiple versions of configurations.
+Whenever a configuration is baselined or distributed,
+the best approach is to unambiguously fix
+the configuration with a symbolic revision number by calling
+\fIrcsfreeze\fR,
+to embed that symbol into the Makefile, and to
+check in the Makefile (using the same symbolic revision number).
+With this approach, old configurations
+can be regenerated easily and reliably.
+.NH
+Usage Statistics
+.PP
+The following usage statistics were collected on two DEC VAX-11/780
+computers of the Purdue Computer Science Department.  Both machines
+are mainly used for research purposes.  Thus, the data
+reflect an environment in which the majority of projects
+involve prototyping and advanced software development,
+but relatively little long-term maintenance.
+.PP
+For the first experiment,
+the \fIci\fR and \fIco\fR operations were instrumented
+to log the number of backward and forward deltas applied.
+The data were collected during a 13 month period
+from Dec. 1982 to Dec. 1983.
+Table I summarizes the results.
+.sp 0
+.nr VS 12p
+.vs 12p
+.TS
+center,box,tab(#);
+c|c|c|c|c s|c s
+c|c|c|c|c s|c s
+l|n|n|n|n n|n n.
+Operation#Total#Total deltas#Mean deltas#Operations#Branch
+	 #operations #applied#applied#with >1 delta#operations
+_
+co     # 7867# 9320#1.18#509#(6%)#203#(3%)
+ci     # 3468# 2207#0.64# 85#(2%)# 75#(2%)
+ci & co#11335#11527#1.02#594#(5%)#278#(2%)
+.TE
+.ce 1
+Table I.  Statistics for \fIco\fR and \fIci\fR operations.
+.nr VS 18p
+.vs 18p
+.PP
+The first two lines show statistics for check-out and check-in;
+the third line shows the combination.
+Recall that \fIci\fR performs an implicit check-out to obtain
+a revision for computing the delta.
+In all measures presented, the most recent revision (stored intact)
+counts as one delta.  The number of deltas applied represents
+the number of passes necessary, where the first `pass' is a copying step.
+.PP
+Note that the check-out operation is executed more than
+twice as frequently as the check-in operation.
+The fourth column gives the mean number of deltas
+applied in all three cases.
+For \fIci\fR, the mean number of deltas applied is less
+than one.
+The reasons are that the initial check-in requires no delta at all, and that
+the only time \fIci\fR requires more than one delta is for branches.
+Column 5 shows the actual number of operations that applied more than one
+delta.
+The last column indicates that branches were not used often.
+.PP
+The last three columns demonstrate that the most recent trunk revision
+is by far the most frequently accessed.
+For RCS, check-out of
+this revision is a simple copy operation, which is the absolute minimum
+given the copy-semantics of \fIco\fR.
+Access to older revisions and branches
+is more common in non-academic environments,
+yet even if access to older deltas were an order
+of magnitude more frequent,
+the combined average number of deltas applied would still be below 1.2.
+Since RCS is faster than SCCS until up to 10 delta applications,
+reverse deltas are clearly the method of choice.
+.PP
+The second experiment, conducted in March of 1984,
+involved surveying the existing RCS files
+on our two machines.  The goal was to determine the mean number of
+revisions per RCS file, as well as the space consumed by them.
+Table II shows the results.  (Tables I and II were produced at different
+times and are unrelated.)
+.sp 0
+.nr VS 12p
+.vs 12p
+.TS
+center,box,tab(#);
+c | c | c | c | c | c | c
+c | c | c | c | c | c | c
+l | n | n | n | n | n | n.
+	  #Total RCS#Total#Mean#Mean size of#Mean size of#Overhead
+	  #files#revisions#revisions#RCS files#revisions
+_
+All files #8033#11133#1.39#6156#5585#1.10
+Files with#1477# 4578#3.10#8074#6041#1.34
+\(>= 2 deltas
+.TE
+.ce 1
+Table II.  Statistics for RCS files.
+.nr VS 18p
+.vs 18p
+.PP
+The mean number of revisions per RCS file is 1.39.
+Columns 5 and 6 show the mean sizes (in bytes) of an RCS file
+and of the latest revision of each RCS file, respectively.
+The `overhead' column contains the ratio of the mean sizes.
+Assuming that all revisions in an RCS file are approximately the same size,
+this ratio gives a measure of the space consumed by the extra revisions.
+.PP
+In our sample, over 80 per cent of the RCS files contained only a single revision.
+The reason is that our
+systems programmers routinely check in all source files
+on the distribution tapes, even though they may never touch them again.
+To get a better indication of how much space savings are possible
+with deltas, all measures with those files
+that contained 2 or more revisions were recomputed.  Only for those files
+is RCS necessary.
+As shown in the second line, the average number of revisions for those files is
+3.10, with an overhead of 1.34.  This means that the extra 2.10 deltas
+require 34 per cent extra space, or
+16 per cent per extra revision.
+Rochkind\u3\d
+measured the space consumed by SCCS, and
+reported an average of 5 revisions per group
+and an overhead of 1.37 (or about 9 per cent per extra revision).
+In a later paper, Glasser\u6\d
+observed an average of 7 revisions per group in a single, large project,
+but provided no overhead figure.
+In his paper on DSEE\u5\d,
+Leblang reported that delta storage combined with blank compression
+results in an overhead of a mere 1\-2 per cent per revision.
+Since leading blanks accounted for about 20 per cent of the surveyed Pascal
+programs, a revision group with 5\-10 members was smaller
+than a single cleartext copy.
+.PP
+The above observations demonstrate clearly that the space needed
+for extra revisions is small.  With delta storage, the luxury of
+keeping multiple revisions online is certainly affordable.
+In fact, introducing a system with delta storage may reduce
+storage requirements, because programmers often save back-up copies
+anyway.  Since back-up copies are stored much more efficiently with deltas,
+introducing a system such as RCS may
+actually free a considerable amount of space.
+.NH
+Survey of Version Control Tools
+.PP
+The need to keep back-up copies of software arose when
+programs and data were no longer stored on paper media, but were entered
+from terminals and stored on disk.
+Back-up copies are desirable for reliability, and many modern editors
+automatically save a back-up copy for every file touched.
+This strategy
+is valuable for short-term back-ups, but not suitable for long-term
+version control, since an existing back-up copy is overwritten whenever the
+corresponding file is edited.
+.PP
+Tape archives are suitable for long-term, offline storage.
+If all changed files are dumped on a back-up tape once per day, old revisions
+remain accessible.  However, tape archives are unsatisfactory
+for version control in several ways.  First, backing up the file
+system every 24 hours does not capture intermediate revisions.
+Secondly, the old revisions are not online,
+and accessing them is tedious and time-consuming.
+In particular, it is impractical to
+compare several old revisions of a group,
+because that may require mounting and searching several tapes.
+Tape archives are important fail-safe tools in the
+event of catastrophic disk failures or accidental deletions,
+but they are ill-suited for version control.
+Conversely, version control tools do not obviate the
+need for tape archives.
+.PP
+A natural technique for keeping several old revisions online is
+to never delete a file.
+Editing a file
+simply creates a new file with the same
+name, but with a different sequence number.
+This technique, available as an option in DEC's VMS operating system,
+turns out to be inadequate for version control.
+First, it is prohibitively expensive in terms of storage costs,
+especially since no data compression techniques are employed.
+Secondly, indiscriminately storing every change produces too many
+revisions, and programmers have difficulties distinguishing them.
+The proliferation of revisions forces programmers to spend much time on
+finding and deleting useless files.
+Thirdly, most of the support functions like locking, logging,
+revision selection,
+and identification described in this paper are not available.
+.PP
+An alternative approach is to separate editing from revision control.
+The user may repeatedly edit a given revision,
+until freezing it with an explicit command.
+Once a revision is frozen, it is stored permanently and can no longer be modified.
+(In RCS, freezing a revisions is done with \fIci\fR.)
+Editing a frozen revision implicitly creates a new one, which
+can again be changed repeatedly until it is frozen itself.
+This approach saves exactly those revisions that the user
+considers important, and keeps the number of revisions manageable.
+IBM's CLEAR/CASTER\u7\d,
+AT&T's SCCS\u3\d,
+CMU's SDC\u8\d
+and DEC's CMS\u9\d,
+are examples of version control systems using this approach.
+CLEAR/CASTER maintains a data base of programs, specifications,
+documentation and messages, using deltas.
+Its goal is to provide control over the development process from a
+management viewpoint.
+SCCS stores multiple revisions of source text in an ancestral tree,
+records a log entry for each revision,
+provides access control, and has facilities
+for uniquely identifying each revision.
+An efficient delta technique
+reduces the space consumed by each revision group.
+SDC is much simpler than SCCS because it stores not more than
+two revisions.  However, it maintains a complete log for all old
+revisions, some of which may be on back-up tape.
+CMS, like SCCS, manages tree-structured revision groups,
+but offers no identification mechanism.
+.PP
+Tools for dealing with configurations are still in a state of flux.
+SCCS, SDC and CMS can be combined with MAKE or MAKE-like programs.
+Since flexible selection rules are missing from all these tools,
+it is sometimes difficult
+to specify precisely which revision of each group
+should be passed to MAKE for building a desired configuration.
+The Xerox Cedar system\u10\d
+provides a `System Modeller' that can rebuild
+a configuration from an arbitrary set of module revisions.
+The revisions of a module are only distinguished by creation time,
+and there is no tool for managing groups.
+Since the selection rules are primitive,
+the System Modeller appears to be somewhat tedious to use.
+Apollo's DSEE\u5\d
+is a sophisticated software engineering environment.
+It manages revision groups in a way similar to SCCS and CMS.  Configurations
+are built using `configuration threads'.
+A configuration thread states which revision of each group
+named in a configuration should be chosen.
+A configuration thread may contain dynamic specifiers
+(e.g., `choose the revisions I am currently working on,
+and the most recent revisions otherwise'), which are bound
+automatically at build time.
+It also provides a notification mechanism for alerting
+maintainers about the need to rebuild a system after a change.
+.PP
+RCS is based on a general model for describing
+multi-version/multi-configuration systems\u11\d.
+The model describes systems using AND/OR graphs, where AND nodes represent
+configurations, and OR nodes represent version groups.
+The model gives rise to a suit of selection rules for
+composing configurations, almost all of which are implemented in RCS.
+The revisions selected by RCS are passed to MAKE for configuration building.
+Revision group management is modelled after SCCS.
+RCS retains SCCS's best features,
+but offers a significantly simpler user interface,
+flexible selection rules, adequate integration with MAKE
+and improved identification.
+A detailed comparison of RCS and SCCS appears in Reference 4.
+.PP
+An important component of all revision control systems
+is a program for computing deltas.
+SCCS and RCS use the program \fIdiff\fR\u2\d,
+which first computes the longest common substring of two
+revisions, and then produces the delta from that substring.
+The delta is simply an edit script consisting of deletion and
+insertion commands that generate one revision from the other.
+.PP
+A delta based on a longest common substring is not necessarily minimal,
+because it does not take advantage of crossing block moves.
+Crossing block moves arise if two or more blocks of lines
+(e.g., procedures)
+appear in a different order in two revisions.
+An edit script derived from a longest common substring
+first deletes the shorter of the two blocks, and then reinserts it.
+Heckel\u12\d
+proposed an algorithm for detecting block moves, but
+since the algorithm is based on heuristics,
+there are conditions
+under which the generated delta is far from minimal.
+DSEE uses this algorithm combined with blank compression,
+apparently with satisfactory overall results.
+A new algorithm that is guaranteed to produce a minimal delta based on
+block moves appears in Reference 13.
+A future release of RCS will use this algorithm.
+.PP
+\fIAcknowledgements\fR:
+Many people have helped make RCS a success by contributed criticisms, suggestions,
+corrections, and even whole new commands (including manual pages).
+The list of people is too long to be
+reproduced here, but my sincere thanks for their help and
+goodwill goes to all of them.
+.sp
+.nr VS 12p
+.vs 12p
+.SH
+Appendix: Synopsis of RCS Operations
+.LP
+.IP "\fIci\fP \fB\- check in revisions\fP"
+.sp 0
+\fICi\fR stores the contents of a working file into the
+corresponding RCS file as a new revision.
+If the RCS file doesn't exist, \fIci\fR creates it.
+\fICi\fR removes the working file, unless one of the options
+\fI\-u\fR or \fI\-l\fR is present.
+For each check-in, \fIci\fR asks for a commentary
+describing the changes relative to the previous revision.
+.sp 1
+\fICi\fR assigns the revision number given by the \fI\-r\fR option;
+if that option is missing, it derives the number from the
+lock held by the user; if there is no lock and locking is not strict,
+\fIci\fR increments the number of the latest revision on the trunk.
+A side branch can only be started by explicitly specifying its
+number with the \fI\-r\fR option during check-in.
+.sp 1
+\fICi\fR also determines
+whether the revision to be checked in is different from the
+previous one, and asks whether to proceed if not.
+This facility simplifies check-in operations for large systems,
+because one need not remember which files were changed.
+.sp 1
+The option \fI\-k\fR searches the checked in file for identification
+markers containing
+the attributes
+revision number, check-in date, author and state, and assigns these
+to the new revision rather than computing them.  This option is
+useful for software distribution: Recipients of distributed software
+using RCS should check in updates with the \fI\-k\fR option.
+This convention guarantees that revision numbers, check-in dates,
+etc., are the same at all sites.
+.IP "\fIco\fP \fB\- check out revisions\fP"
+.sp 0
+\fICo\fR retrieves revisions according to revision number,
+date, author and state attributes.  It either places the revision
+into the working file, or prints it on the standard output.
+\fICo\fR always expands the identification markers.
+.IP "\fIident\fP \fB\- extract identification markers\fP"
+.sp 0
+\fIIdent\fR extracts the identification markers expanded by \fIco\fR
+from any file and prints them.
+.IP "\fIrcs\fP \fB\- change RCS file attributes\fP"
+.sp 0
+\fIRcs\fR is an administrative operation that changes access lists,
+locks, unlocks, breaks locks, toggles the strict-locking feature,
+sets state attributes and symbolic revision numbers, changes the
+description, and deletes revisions.  A revision can
+only be deleted if it is not the fork of a side branch.
+.br
+.ne 10
+.IP "\fIrcsclean\fP \fB\- clean working directory\fP"
+.sp 0
+\fIRcsclean\fR removes working files that were checked out but never changed.*
+.FS *
+The \fIrcsclean\fP and \fIrcsfreeze\fP commands
+are optional and are not always installed.
+.FE
+.IP "\fIrcsdiff\fP \fB\- compare revisions\fP"
+.sp 0
+\fIRcsdiff\fR compares two revisions and prints their
+difference, using the UNIX tool \fIdiff\fR.
+One of the revisions compared may be checked out.
+This command is useful for finding out about changes.
+.IP "\fIrcsfreeze\fP \fB\- freeze a configuration\fP"
+.sp 0
+\fIRcsfreeze\fR assigns the same symbolic revision number
+to a given revision in all RCS files.
+This command is useful for accurately recording a configuration.*
+.IP "\fIrcsmerge\fP \fB\- merge revisions\fP"
+.sp 0
+\fIRcsmerge\fR merges two revisions, \fIrev1\fR and \fIrev2\fR,
+with respect to a common ancestor.
+A 3-way file comparison determines the segments of lines that
+are (a) the same in all three revisions, or (b) the same in 2 revisions,
+or (c) different in all three.  For all segments of type (b) where
+\fIrev1\fR is the differing revision,
+the segment in \fIrev1\fR replaces the corresponding segment of \fIrev2\fR.
+Type (c) indicates an overlapping change, is flagged as an error, and requires user
+intervention to select the correct alternative.
+.IP "\fIrlog\fP \fB\- read log messages\fP"
+.sp 0
+\fIRlog\fR prints the log messages and other information in an RCS file.
+.bp
+.LP
+.nr VS 12p
+.vs 12p
+.]<
+.ds [F 1
+.]-
+.ds [K FELD02
+.ds [K MakeArticle
+.ds [A Feldman, Stuart I.
+.ds [D March 1979
+.ds [T Make\*-A Program for Maintaining Computer Programs
+.ds [J Software\*-Practice & Experience
+.ds [V 9
+.ds [N 3
+.ds [P 255-265
+.nr [P 1
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 1 journal-article
+.ds [F 2
+.]-
+.ds [K HUNT01
+.ds [T An Algorithm for Differential File Comparison
+.ds [A Hunt, James W.
+.as [A " and McIlroy, M. D.
+.ds [I Computing Science Technical Report, Bell Laboratories
+.ds [R 41
+.ds [D June 1976
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 4 tech-report
+.ds [F 3
+.]-
+.ds [K SCCS
+.ds [A Rochkind, Marc J.
+.ds [D Dec. 1975
+.ds [T The Source Code Control System
+.ds [J IEEE Transactions on Software Engineering
+.ds [V SE-1
+.ds [N 4
+.ds [P 364-370
+.nr [P 1
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 1 journal-article
+.ds [F 4
+.]-
+.ds [K TICH08
+.ds [T Design, Implementation, and Evaluation of a Revision Control System
+.ds [A Tichy, Walter F.
+.ds [B Proceedings of the 6th International Conference on Software Engineering
+.ds [I ACM, IEEE, IPS, NBS
+.ds [D September 1982
+.ds [P 58-67
+.nr [P 1
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 3 article-in-book
+.ds [F 5
+.]-
+.ds [K LEBL01
+.ds [A Leblang, David B.
+.as [A " and Chase, Robert P.
+.ds [T Computer-Aided Software Engineering in a Distributed Workstation Environment
+.ds [O Proceedings of the ACM SIGSOFT/SIGPLAN Software Engineering Symposium
+.as [O " on Practical Software Development Environments.
+.ds [J SIGPLAN Notices
+.ds [V 19
+.ds [N 5
+.ds [D May 1984
+.ds [P 104-112
+.nr [P 1
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 1 journal-article
+.ds [F 1
+.ds [F 3
+.ds [F 6
+.]-
+.ds [K SCCSEval
+.ds [A Glasser, Alan L.
+.ds [D Nov. 1978
+.ds [T The Evolution of a Source Code Control System
+.ds [J Software Engineering Notes
+.ds [V 3
+.ds [N 5
+.ds [P 122-125
+.nr [P 1
+.ds [O Proceedings of the Software Quality and Assurance Workshop.
+.nr [T 0
+.nr [A 1
+.nr [O 1
+.][ 1 journal-article
+.ds [F 5
+.ds [F 7
+.]-
+.ds [K IBMClearCaster
+.ds [A Brown, H.B.
+.ds [D 1970
+.ds [T The Clear/Caster System
+.ds [J Nato Conference on Software Engineering, Rome
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 1 journal-article
+.ds [F 3
+.ds [F 8
+.]-
+.ds [K HabermannSDC
+.ds [A Habermann, A. Nico
+.ds [D Jan. 1979
+.ds [T A Software Development Control System
+.ds [I Technical Report, Carnegie-Mellon University, Department of Computer Science
+.nr [T 0
+.nr [A 0
+.nr [O 0
+.][ 2 book
+.ds [F 9
+.]-
+.ds [K CMS
+.ds [A DEC
+.ds [T Code Management System
+.ds [I Digital Equipment Corporation
+.ds [O Document No.\ EA-23134-82
+.ds [D 1982
+.nr [T 0
+.nr [A 0
+.nr [O 0
+.][ 2 book
+.ds [F 10
+.]-
+.ds [K LAMP01
+.ds [A Lampson, Butler W.
+.as [A " and Schmidt, Eric E.
+.ds [T Practical Use of a Polymorphic Applicative Language
+.ds [B Proceedings of the 10th Symposium on Principles of Programming Languages
+.ds [I ACM
+.ds [P 237-255
+.nr [P 1
+.ds [D January 1983
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 3 article-in-book
+.ds [F 5
+.ds [F 11
+.]-
+.ds [K TICH07
+.ds [T A Data Model for Programming Support Environments and its Application
+.ds [A Tichy, Walter F.
+.ds [B Automated Tools for Information System Design and Development
+.ds [E Hans-Jochen Schneider and Anthony I. Wasserman
+.ds [C Amsterdam
+.ds [I North-Holland Publishing Company
+.ds [D 1982
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 3 article-in-book
+.ds [F 4
+.ds [F 2
+.ds [F 12
+.]-
+.ds [K HECK01
+.ds [T A Technique for Isolating Differences Between Files
+.ds [A Heckel, Paul
+.ds [J Communications of the ACM
+.ds [D April 1978
+.ds [V 21
+.ds [N 4
+.ds [P 264-268
+.nr [P 1
+.nr [T 0
+.nr [A 0
+.nr [O 0
+.][ 1 journal-article
+.ds [F 13
+.]-
+.ds [K TICH11
+.ds [T The String-to-String Correction Problem with Block Moves
+.ds [A Tichy, Walter F.
+.ds [D Nov. 1984
+.ds [J ACM Transactions on Computer Systems
+.ds [V 2
+.ds [N 4
+.ds [P 309-321
+.nr [P 1
+.nr [T 0
+.nr [A 1
+.nr [O 0
+.][ 1 journal-article
+.]>
diff --git a/gnu/usr.bin/rcs/doc/rcs_func.ms b/gnu/usr.bin/rcs/doc/rcs_func.ms
new file mode 100644
index 0000000000000..9818086c3de45
--- /dev/null
+++ b/gnu/usr.bin/rcs/doc/rcs_func.ms
@@ -0,0 +1,95 @@
+.SH
+Functions of RCS (Revision Control System)
+.PP
+RCS manages software libraries. It greatly increases programmer productivity
+by providing the following functions.
+.IP 1.
+RCS stores and retrieves multiple revisions of program and other text.
+Thus, one can maintain one or more releases while developing the next
+release, with a minimum of space overhead. Changes no longer destroy the
+original -- previous revisions remain accessible.
+.RS
+.IP a.
+Maintains each module as a tree of revisions.
+.IP b.
+Project libraries can
+be organized centrally, decentralized, or any way you like.
+.IP c.
+RCS works for any type of text: programs, documentation, memos, papers,
+graphics, VLSI layouts, form letters, etc.
+.RE
+.IP 2.
+RCS maintains a complete history of changes.
+Thus, one can find out what happened to a module easily
+and quickly, without having to compare source listings or
+having to track down colleagues.
+.RS
+.IP a.
+RCS performs automatic record keeping.
+.IP b.
+RCS logs all changes automatically.
+.IP c.
+RCS guarantees project continuity.
+.RE
+.IP 3.
+RCS manages multiple lines of development.
+.IP 4.
+RCS can merge multiple lines of development.
+Thus, when several parallel lines of development must be consolidated
+into one line, the merging of changes is automatic.
+.IP 5.
+RCS flags coding conflicts.
+If two or more lines of development modify the same section of code,
+RCS can alert programmers about overlapping changes.
+.IP 6.
+RCS resolves access conflicts.
+When two or more programmers wish to modify the same revision,
+RCS alerts the programmers and makes sure that one modification won't wipe
+out the other one.
+.IP 7.
+RCS provides high-level retrieval functions.
+Revisions can be retrieved according to ranges of revision numbers,
+symbolic names, dates, authors, and states.
+.IP 8.
+RCS provides release and configuration control.
+Revisions can be marked as released, stable, experimental, etc.
+Configurations of modules can be described simply and directly.
+.IP 9.
+RCS performs automatic identification of modules with name, revision
+number, creation time, author, etc.
+Thus, it is always possible to determine which revisions of which
+modules make up a given configuration.
+.IP 10.
+Provides high-level management visibility.
+Thus, it is easy to track the status of a software project.
+.RS
+.IP a.
+RCS provides a complete change history.
+.IP b.
+RCS records who did what when to which revision of which module.
+.RE
+.IP 11.
+RCS is fully compatible with existing software development tools.
+RCS is unobtrusive -- its interface to the file system is such that
+all your existing software tools can be used as before.
+.IP 12.
+RCS' basic user interface is extremely simple. The novice need to learn
+only two commands. Its more sophisticated features have been
+tuned towards advanced software development environments and the
+experienced software professional.
+.IP 13.
+RCS simplifies software distribution if customers
+maintain sources with RCS also. This technique assures proper
+identification of versions and configurations, and tracking of customer
+modifications. Customer modifications can be merged into distributed
+versions locally or by the development group.
+.IP 14.
+RCS needs little extra space for the revisions (only the differences).
+If intermediate revisions are deleted, the corresponding
+differences are compressed into the shortest possible form.
+.IP 15.
+RCS is implemented with reverse deltas. This means that
+the latest revision, which is the one that is accessed most often,
+is stored intact. All others are regenerated from the latest one
+by applying reverse deltas (backward differences). This
+results in fast access time for the revision needed most often.
diff --git a/gnu/usr.bin/rcs/ident/Makefile b/gnu/usr.bin/rcs/ident/Makefile
new file mode 100644
index 0000000000000..f28f8d3c5b712
--- /dev/null
+++ b/gnu/usr.bin/rcs/ident/Makefile
@@ -0,0 +1,8 @@
+PROG=	ident
+SRCS=	ident.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=  ${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/ident/ident.1 b/gnu/usr.bin/rcs/ident/ident.1
new file mode 100644
index 0000000000000..253a2ce72724a
--- /dev/null
+++ b/gnu/usr.bin/rcs/ident/ident.1
@@ -0,0 +1,182 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+.ds iD \\$3 \\$4 \\$5 \\$6 \\$7
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.ds u \&\s-1UTC\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH IDENT 1 \*(Dt GNU
+.SH NAME
+ident \- identify RCS keyword strings in files
+.SH SYNOPSIS
+.B ident
+[
+.B \-q
+] [
+.B \-V
+] [
+.I file
+\&.\|.\|. ]
+.SH DESCRIPTION
+.B ident
+searches for all instances of the pattern
+.BI $ keyword : "\ text\ " $
+in the named files or, if no files are named, the standard input.
+.PP
+These patterns are normally inserted automatically by the \*r command
+.BR co (1),
+but can also be inserted manually.
+The option
+.B \-q
+suppresses
+the warning given if there are no patterns in a file.
+The option
+.B \-V
+prints
+.BR ident 's
+version number.
+.PP
+.B ident
+works on text files as well as object files and dumps.
+For example, if the C program in
+.B f.c
+contains
+.IP
+.ft 3
+#include <stdio.h>
+.br
+static char const rcsid[] =
+.br
+  \&"$\&Id: f.c,v \*(iD $\&";
+.br
+int main() { return printf(\&"%s\en\&", rcsid) == EOF; }
+.ft P
+.LP
+and
+.B f.c
+is compiled into
+.BR f.o ,
+then the command
+.IP
+.B "ident  f.c  f.o"
+.LP
+will output
+.nf
+.IP
+.ft 3
+f.c:
+    $\&Id: f.c,v \*(iD $
+f.o:
+    $\&Id: f.c,v \*(iD $
+.ft
+.fi
+.PP
+If a C program defines a string like
+.B rcsid
+above but does not use it,
+.BR lint (1)
+may complain, and some C compilers will optimize away the string.
+The most reliable solution is to have the program use the
+.B rcsid
+string, as shown in the example above.
+.PP
+.B ident
+finds all instances of the
+.BI $ keyword : "\ text\ " $
+pattern, even if
+.I keyword
+is not actually an \*r-supported keyword.
+This gives you information about nonstandard keywords like
+.BR $\&XConsortium$ .
+.SH KEYWORDS
+Here is the list of keywords currently maintained by
+.BR co (1).
+All times are given in Coordinated Universal Time (\*u,
+sometimes called \&\s-1GMT\s0) by default, but if the files
+were checked out with
+.BR co 's
+.BI \-z zone
+option, times are given with a numeric time zone indication appended.
+.TP
+.B $\&Author$
+The login name of the user who checked in the revision.
+.TP
+.B $\&Date$
+The date and time the revision was checked in.
+.TP
+.B $\&Header$
+A standard header containing the full pathname of the \*r file, the
+revision number, the date and time, the author, the state,
+and the locker (if locked).
+.TP
+.B $\&Id$
+Same as
+.BR $\&Header$ ,
+except that the \*r filename is without a path.
+.TP
+.B $\&Locker$
+The login name of the user who locked the revision (empty if not locked).
+.TP
+.B $\&Log$
+The log message supplied during checkin.
+For
+.BR ident 's
+purposes, this is equivalent to
+.BR $\&RCSfile$ .
+.TP
+.B $\&Name$
+The symbolic name used to check out the revision, if any.
+.TP
+.B $\&RCSfile$
+The name of the \*r file without a path.
+.TP
+.B $\&Revision$
+The revision number assigned to the revision.
+.TP
+.B $\&Source$
+The full pathname of the \*r file.
+.TP
+.B $\&State$
+The state assigned to the revision with the
+.B \-s
+option of
+.BR rcs (1)
+or
+.BR ci (1).
+.PP
+.BR co (1)
+represents the following characters in keyword values by escape sequences
+to keep keyword strings well-formed.
+.LP
+.RS
+.nf
+.ne 6
+.ta \w'newline  'u
+\f2char	escape sequence\fP
+tab	\f3\et\fP
+newline	\f3\en\fP
+space	\f3\e040
+$	\e044
+\e	\e\e\fP
+.fi
+.RE
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1992, 1993 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), rcs(1), rcsdiff(1), rcsintro(1), rcsmerge(1), rlog(1),
+rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
diff --git a/gnu/usr.bin/rcs/ident/ident.c b/gnu/usr.bin/rcs/ident/ident.c
new file mode 100644
index 0000000000000..9b8bf57365ec7
--- /dev/null
+++ b/gnu/usr.bin/rcs/ident/ident.c
@@ -0,0 +1,270 @@
+/* Identify RCS keyword strings in files.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.9  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.8  1995/06/01 16:23:43  eggert
+ * (exiterr, reportError): New functions, needed for DOS and OS/2 ports.
+ * (scanfile): Use them.
+ *
+ * Revision 5.7  1994/03/20 04:52:58  eggert
+ * Remove `exiting' from identExit.
+ *
+ * Revision 5.6  1993/11/09 17:40:15  eggert
+ * Add -V.
+ *
+ * Revision 5.5  1993/11/03 17:42:27  eggert
+ * Test for char == EOF, not char < 0.
+ *
+ * Revision 5.4  1992/01/24  18:44:19  eggert
+ * lint -> RCS_lint
+ *
+ * Revision 5.3  1991/09/10  22:15:46  eggert
+ * Open files with FOPEN_R, not FOPEN_R_WORK,
+ * because they might be executables, not working files.
+ *
+ * Revision 5.2  1991/08/19  03:13:55  eggert
+ * Report read errors immediately.
+ *
+ * Revision 5.1  1991/02/25  07:12:37  eggert
+ * Don't report empty keywords.  Check for I/O errors.
+ *
+ * Revision 5.0  1990/08/22  08:12:37  eggert
+ * Don't limit output to known keywords.
+ * Remove arbitrary limits and lint.  Ansify and Posixate.
+ *
+ * Revision 4.5  89/05/01  15:11:54  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.4  87/10/23  17:09:57  narten
+ * added exit(0) so exit return code would be non random
+ *
+ * Revision 4.3  87/10/18  10:23:55  narten
+ * Updating version numbers. Changes relative to 1.1 are actually relative
+ * to 4.1
+ *
+ * Revision 1.3  87/07/09  09:20:52  trinkle
+ * Added check to make sure there is at least one arg before comparing argv[1]
+ * with "-q".  This necessary on machines that don't allow dereferncing null
+ * pointers (i.e. Suns).
+ *
+ * Revision 1.2  87/03/27  14:21:47  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/10  16:31:02  wft
+ * Added option -q and input from reading stdin.
+ * Marker matching is now done with trymatch() (independent of keywords).
+ *
+ * Revision 3.4  83/02/18  17:37:49  wft
+ * removed printing of new line after last file.
+ *
+ * Revision 3.3  82/12/04  12:48:55  wft
+ * Added LOCKER.
+ *
+ * Revision 3.2  82/11/28  18:24:17  wft
+ * removed Suffix; added ungetc to avoid skipping over trailing KDELIM.
+ *
+ * Revision 3.1  82/10/13  15:58:51  wft
+ * fixed type of variables receiving from getc() (char-->int).
+*/
+
+#include  "rcsbase.h"
+
+static int match P((FILE*));
+static int scanfile P((FILE*,char const*,int));
+static void reportError P((char const*));
+
+mainProg(identId, "ident", "$FreeBSD$")
+/*  Ident searches the named files for all occurrences
+ *  of the pattern $@: text $ where @ is a keyword.
+ */
+
+{
+   FILE *fp;
+   int quiet = 0;
+   int status = EXIT_SUCCESS;
+   char const *a;
+
+   while ((a = *++argv)  &&  *a=='-')
+	while (*++a)
+	    switch (*a) {
+		case 'q':
+		    quiet = 1;
+		    break;
+
+		case 'V':
+		    VOID printf("RCS version %s\n", RCS_version_string);
+		    quiet = -1;
+		    break;
+
+		default:
+		    VOID fprintf(stderr,
+			"ident: usage: ident -{qV} [file...]\n"
+		    );
+		    exitmain(EXIT_FAILURE);
+		    break;
+	    }
+
+   if (0 <= quiet)
+       if (!a)
+	    VOID scanfile(stdin, (char*)0, quiet);
+       else
+	    do {
+		if (!(fp = fopen(a, FOPEN_RB))) {
+		    reportError(a);
+		    status = EXIT_FAILURE;
+		} else if (
+		    scanfile(fp, a, quiet) != 0
+		    || (argv[1]  &&  putchar('\n') == EOF)
+		)
+		    break;
+	    } while ((a = *++argv));
+
+   if (ferror(stdout) || fclose(stdout)!=0) {
+      reportError("standard output");
+      status = EXIT_FAILURE;
+   }
+   exitmain(status);
+}
+
+#if RCS_lint
+#	define exiterr identExit
+#endif
+	void
+exiterr()
+{
+	_exit(EXIT_FAILURE);
+}
+
+	static void
+reportError(s)
+	char const *s;
+{
+	int e = errno;
+	VOID fprintf(stderr, "%s error: ", cmdid);
+	errno = e;
+	perror(s);
+}
+
+
+	static int
+scanfile(file, name, quiet)
+	register FILE *file;
+	char const *name;
+	int quiet;
+/* Function: scan an open file with descriptor file for keywords.
+ * Return -1 if there's a write error; exit immediately on a read error.
+ */
+{
+   register int c;
+
+   if (name) {
+      VOID printf("%s:\n", name);
+      if (ferror(stdout))
+	 return -1;
+   } else
+      name = "standard input";
+   c = 0;
+   while (c != EOF  ||  ! (feof(file)|ferror(file))) {
+      if (c == KDELIM) {
+	 if ((c = match(file)))
+	    continue;
+	 if (ferror(stdout))
+	    return -1;
+	 quiet = true;
+      }
+      c = getc(file);
+   }
+   if (ferror(file) || fclose(file) != 0) {
+      reportError(name);
+      /*
+      * The following is equivalent to exit(EXIT_FAILURE), but we invoke
+      * exiterr to keep lint happy.  The DOS and OS/2 ports need exiterr.
+      */
+      VOID fflush(stderr);
+      VOID fflush(stdout);
+      exiterr();
+   }
+   if (!quiet)
+      VOID fprintf(stderr, "%s warning: no id keywords in %s\n", cmdid, name);
+   return 0;
+}
+
+
+
+	static int
+match(fp)   /* group substring between two KDELIM's; then do pattern match */
+   register FILE *fp;
+{
+   char line[BUFSIZ];
+   register int c;
+   register char * tp;
+
+   tp = line;
+   while ((c = getc(fp)) != VDELIM) {
+      if (c == EOF  &&  feof(fp) | ferror(fp))
+	 return c;
+      switch (ctab[c]) {
+	 case LETTER: case Letter: case DIGIT:
+	    *tp++ = c;
+	    if (tp < line+sizeof(line)-4)
+	       break;
+	    /* fall into */
+	 default:
+	    return c ? c : '\n'/* anything but 0 or KDELIM or EOF */;
+      }
+   }
+   if (tp == line)
+      return c;
+   *tp++ = c;
+   if ((c = getc(fp)) != ' ')
+      return c ? c : '\n';
+   *tp++ = c;
+   while( (c = getc(fp)) != KDELIM ) {
+      if (c == EOF  &&  feof(fp) | ferror(fp))
+	    return c;
+      switch (ctab[c]) {
+	 default:
+	    *tp++ = c;
+	    if (tp < line+sizeof(line)-2)
+	       break;
+	    /* fall into */
+	 case NEWLN: case UNKN:
+	    return c ? c : '\n';
+      }
+   }
+   if (tp[-1] != ' ')
+      return c;
+   *tp++ = c;     /*append trailing KDELIM*/
+   *tp   = '\0';
+   VOID printf("     %c%s\n", KDELIM, line);
+   return 0;
+}
diff --git a/gnu/usr.bin/rcs/lib/Makefile b/gnu/usr.bin/rcs/lib/Makefile
new file mode 100644
index 0000000000000..f21fda1e81001
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/Makefile
@@ -0,0 +1,14 @@
+# $FreeBSD$
+
+# Define FSYNC_ALL to get slower but safer writes in case of crashes in
+# the middle of CVS/RCS changes
+#CFLAGS += -DFSYNC_ALL
+
+LIB     = rcs
+SRCS    = maketime.c partime.c rcsedit.c rcsfcmp.c rcsfnms.c rcsgen.c \
+	  rcskeep.c rcskeys.c rcslex.c rcsmap.c rcsrev.c rcssyn.c rcstime.c \
+	  rcsutil.c merger.c version.c
+
+INTERNALLIB=
+
+.include <bsd.lib.mk>
diff --git a/gnu/usr.bin/rcs/lib/conf.h b/gnu/usr.bin/rcs/lib/conf.h
new file mode 100644
index 0000000000000..96ec07d6c8754
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/conf.h
@@ -0,0 +1,400 @@
+/* RCS compile-time configuration */
+
+	/* $FreeBSD$ */
+
+/*
+ * This file is generated automatically.
+ * If you edit it by hand your changes may be lost.
+ * Instead, please try to fix conf.sh,
+ * and send your fixes to rcs-bugs@cs.purdue.edu.
+ */
+
+#define exitmain(n) return n /* how to exit from main() */
+/* #define _POSIX_C_SOURCE 2147483647L */ /* if strict C + Posix 1003.1b-1993 or later */
+/* #define _POSIX_SOURCE */ /* if strict C + Posix 1003.1-1990 */
+
+#include <errno.h>
+#include <stdio.h>
+#include <time.h>
+
+/* Comment out #include lines below that do not work.  */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <limits.h>
+/* #include <mach/mach.h> */
+/* #include <net/errno.h> */
+#include <pwd.h>
+/* #include <siginfo.h> */
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+/* #include <ucontext.h> */
+#include <unistd.h>
+#include <utime.h>
+/* #include <vfork.h> */
+
+/* Define boolean symbols to be 0 (false, the default), or 1 (true).  */
+#define has_sys_param_h 1 /* Does #include <sys/param.h> work?  */
+/* extern int errno; */ /* Uncomment if <errno.h> doesn't declare errno.  */
+#define has_readlink 1 /* Does readlink() work?  */
+#define readlink_isreg_errno EINVAL /* errno after readlink on regular file */
+
+#if has_readlink && !defined(MAXSYMLINKS)
+#	if has_sys_param_h
+#		include <sys/param.h>
+#	endif
+#	ifndef MAXSYMLINKS
+#		define MAXSYMLINKS 20 /* BSD; not standard yet */
+#	endif
+#endif
+
+/* Comment out the typedefs below if the types are already declared.  */
+/* Fix any uncommented typedefs that are wrong.  */
+/* typedef int mode_t; */
+/* typedef long off_t; */
+/* typedef int pid_t; */
+/* typedef int sig_atomic_t; */
+/* typedef unsigned size_t; */
+/* typedef int ssize_t; */
+/* typedef long time_t; */
+/* typedef int uid_t; */
+
+/* Comment out the keyword definitions below if the keywords work.  */
+/* #define const */
+/* #define volatile */
+
+/* Define boolean symbols to be 0 (false, the default), or 1 (true).  */
+#define has_prototypes 1 /* Do function prototypes work?  */
+#define has_stdarg 1 /* Does <stdarg.h> work?  */
+/* #define has_varargs ? */ /* Does <varargs.h> work?  */
+#define va_start_args 2 /* How many args does va_start() take?  */
+
+#if O_BINARY
+	/* Text and binary i/o behave differently.  */
+	/* This is incompatible with Posix and Unix.  */
+#	define FOPEN_RB "rb"
+#	define FOPEN_R_WORK (Expand==BINARY_EXPAND ? "r" : "rb")
+#	define FOPEN_WB "wb"
+#	define FOPEN_W_WORK (Expand==BINARY_EXPAND ? "w" : "wb")
+#	define FOPEN_WPLUS_WORK (Expand==BINARY_EXPAND ? "w+" : "w+b")
+#	define OPEN_O_BINARY O_BINARY
+#else
+	/*
+	* Text and binary i/o behave the same.
+	* Omit "b", since some nonstandard hosts reject it.
+	*/
+#	define FOPEN_RB "r"
+#	define FOPEN_R_WORK "r"
+#	define FOPEN_WB "w"
+#	define FOPEN_W_WORK "w"
+#	define FOPEN_WPLUS_WORK "w+"
+#	define OPEN_O_BINARY 0
+#endif
+
+/* This may need changing on non-Unix systems (notably DOS).  */
+#define OPEN_CREAT_READONLY (S_IRUSR|S_IRGRP|S_IROTH) /* lock file mode */
+#define OPEN_O_LOCK 0 /* extra open flags for creating lock file */
+#define OPEN_O_WRONLY O_WRONLY /* main open flag for creating a lock file */
+
+/* Define or comment out the following symbols as needed.  */
+#if has_prototypes
+#	define P(params) params
+#else
+#	define P(params) ()
+#endif
+#if has_stdarg
+#	include <stdarg.h>
+#else
+#	if has_varargs
+#		include <varargs.h>
+#	else
+		typedef char *va_list;
+#		define va_dcl int va_alist;
+#		define va_start(ap) ((ap) = (va_list)&va_alist)
+#		define va_arg(ap,t) (((t*) ((ap)+=sizeof(t)))  [-1])
+#		define va_end(ap)
+#	endif
+#endif
+#if va_start_args == 2
+#	define vararg_start va_start
+#else
+#	define vararg_start(ap,p) va_start(ap)
+#endif
+#define bad_chmod_close 0 /* Can chmod() close file descriptors?  */
+#define bad_creat0 0 /* Do writes fail after creat(f,0)?  */
+#define bad_fopen_wplus 0 /* Does fopen(f,"w+") fail to truncate f?  */
+#define getlogin_is_secure 0 /* Is getlogin() secure?  Usually it's not.  */
+#define has_attribute_noreturn 1 /* Does __attribute__((noreturn)) work?  */
+#if has_attribute_noreturn
+#	define exiting __attribute__((noreturn))
+#else
+#	define exiting
+#endif
+#define has_dirent 1 /* Do opendir(), readdir(), closedir() work?  */
+#define void_closedir 0 /* Does closedir() yield void?  */
+#define has_fchmod 1 /* Does fchmod() work?  */
+#define has_fflush_input 0 /* Does fflush() work on input files?  */
+#define has_fputs 1 /* Does fputs() work?  */
+#define has_ftruncate 1 /* Does ftruncate() work?  */
+#define has_getuid 1 /* Does getuid() work?  */
+#define has_getpwuid 1 /* Does getpwuid() work?  */
+#define has_memcmp 1 /* Does memcmp() work?  */
+#define has_memcpy 1 /* Does memcpy() work?  */
+#define has_memmove 1 /* Does memmove() work?  */
+#define has_map_fd 0 /* Does map_fd() work?  */
+#define has_mmap 1 /* Does mmap() work on regular files?  */
+#define has_madvise 0 /* Does madvise() work?  */
+#define mmap_signal SIGBUS /* signal received if you reference nonexistent part of mmapped file */
+#define has_rename 1 /* Does rename() work?  */
+#define bad_a_rename 0 /* Does rename(A,B) fail if A is unwritable?  */
+#define bad_b_rename 0 /* Does rename(A,B) fail if B is unwritable?  */
+#define bad_NFS_rename 0 /* Can rename(A,B) falsely report success?  */
+/* typedef int void; */ /* Some ancient compilers need this.  */
+#define VOID (void) /* 'VOID e;' discards the value of an expression 'e'.  */
+#define has_seteuid 1 /* Does seteuid() work?  See ../INSTALL.RCS.  */
+#define has_setreuid 0 /* Does setreuid() work?  See ../INSTALL.RCS.  */
+#define has_setuid 1 /* Does setuid() exist?  */
+#define has_sigaction 1 /* Does struct sigaction work?  */
+#define has_sa_sigaction 1 /* Does struct sigaction have sa_sigaction?  */
+#define has_signal 1 /* Does signal() work?  */
+#define signal_type void /* type returned by signal handlers */
+#define sig_zaps_handler 0 /* Must a signal handler reinvoke signal()?  */
+/* #define has_sigblock ? */ /* Does sigblock() work?  */
+/* #define sigmask(s) (1 << ((s)-1)) */ /* Yield mask for signal number.  */
+typedef size_t fread_type; /* type returned by fread() and fwrite() */
+typedef size_t freadarg_type; /* type of their size arguments */
+typedef void *malloc_type; /* type returned by malloc() */
+#define has_getcwd 1 /* Does getcwd() work?  */
+/* #define has_getwd ? */ /* Does getwd() work?  */
+#define needs_getabsname 0 /* Must we define getabsname?  */
+#define has_mktemp 1 /* Does mktemp() work?  */
+#define has_mkstemp 1 /* Does mkstemp() work?  */
+#define has_NFS 1 /* Might NFS be used?  */
+#define has_psiginfo 0 /* Does psiginfo() work?  */
+#define has_psignal 1 /* Does psignal() work?  */
+/* #define has_si_errno ? */ /* Does siginfo_t have si_errno?  */
+/* #define has_sys_siglist ? */ /* Does sys_siglist[] work?  */
+/* #define strchr index */ /* Use old-fashioned name for strchr()?  */
+/* #define strrchr rindex */ /* Use old-fashioned name for strrchr()?  */
+#define bad_unlink 0 /* Does unlink() fail on unwritable files?  */
+#define has_vfork 1 /* Does vfork() work?  */
+#define has_fork 1 /* Does fork() work?  */
+#define has_spawn 0 /* Does spawn*() work?  */
+#define has_waitpid 1 /* Does waitpid() work?  */
+#define bad_wait_if_SIGCHLD_ignored 0 /* Does ignoring SIGCHLD break wait()?  */
+#define RCS_SHELL "/bin/sh" /* shell to run RCS subprograms */
+#define has_printf_dot 1 /* Does "%.2d" print leading 0?  */
+#define has_vfprintf 1 /* Does vfprintf() work?  */
+#define has_attribute_format_printf 1 /* Does __attribute__((format(printf,N,N+1))) work?  */
+#if has_attribute_format_printf
+#	define printf_string(m, n) __attribute__((format(printf, m, n)))
+#else
+#	define printf_string(m, n)
+#endif
+#if has_attribute_format_printf && has_attribute_noreturn
+	/* Work around a bug in GCC 2.5.x.  */
+#	define printf_string_exiting(m, n) __attribute__((format(printf, m, n), noreturn))
+#else
+#	define printf_string_exiting(m, n) printf_string(m, n) exiting
+#endif
+/* #define has__doprintf ? */ /* Does _doprintf() work?  */
+/* #define has__doprnt ? */ /* Does _doprnt() work?  */
+/* #undef EXIT_FAILURE */ /* Uncomment this if EXIT_FAILURE is broken.  */
+#define large_memory 1 /* Can main memory hold entire RCS files?  */
+#ifndef LONG_MAX
+#define LONG_MAX 2147483647L /* long maximum */
+#endif
+/* Do struct stat s and t describe the same file?  Answer d if unknown.  */
+#define same_file(s,t,d) ((s).st_ino==(t).st_ino && (s).st_dev==(t).st_dev)
+#define has_utimbuf 1 /* Does struct utimbuf work?  */
+#define CO "/usr/bin/co" /* name of 'co' program */
+#define COMPAT2 0 /* Are version 2 files supported?  */
+#define DIFF "/usr/bin/diff" /* name of 'diff' program */
+#define DIFF3 "/usr/bin/diff3" /* name of 'diff3' program */
+#define DIFF3_BIN 1 /* Is diff3 user-visible (not the /usr/lib auxiliary)?  */
+#define DIFFFLAGS "-an" /* Make diff output suitable for RCS.  */
+#define DIFF_L 1 /* Does diff -L work?  */
+#define DIFF_SUCCESS 0 /* DIFF status if no differences are found */
+#define DIFF_FAILURE 1 /* DIFF status if differences are found */
+#define DIFF_TROUBLE 2 /* DIFF status if trouble */
+#define ED "/bin/ed" /* name of 'ed' program (used only if !DIFF3_BIN) */
+#define MERGE "/usr/bin/merge" /* name of 'merge' program */
+#define TMPDIR "/tmp" /* default directory for temporary files */
+#define SLASH '/' /* principal filename separator */
+#define SLASHes '/' /* `case SLASHes:' labels all filename separators */
+#define isSLASH(c) ((c) == SLASH) /* Is arg a filename separator?  */
+#define ROOTPATH(p) isSLASH((p)[0]) /* Is p an absolute pathname?  */
+#define X_DEFAULT ",v/" /* default value for -x option */
+#define SLASHSLASH_is_SLASH 1 /* Are // and / the same directory?  */
+#define ALL_ABSOLUTE 1 /* Do all subprograms satisfy ROOTPATH?  */
+#define DIFF_ABSOLUTE 1 /* Is ROOTPATH(DIFF) true?  */
+#define SENDMAIL "/usr/sbin/sendmail" /* how to send mail */
+#define TZ_must_be_set 0 /* Must TZ be set for gmtime() to work?  */
+
+
+
+/* Adjust the following declarations as needed.  */
+
+
+/* The rest is for the benefit of non-standard, traditional hosts.  */
+/* Don't bother to declare functions that in traditional hosts do not appear, */
+/* or are declared in .h files, or return int or void.  */
+
+
+/* traditional BSD */
+
+#if has_sys_siglist && !defined(sys_siglist)
+	extern char const * const sys_siglist[];
+#endif
+
+
+/* Posix (ISO/IEC 9945-1: 1990 / IEEE Std 1003.1-1990) */
+
+/* <fcntl.h> */
+#ifdef O_CREAT
+#	define open_can_creat 1
+#else
+#	define open_can_creat 0
+#	define O_RDONLY 0
+#	define O_WRONLY 1
+#	define O_RDWR 2
+#	define O_CREAT 01000
+#	define O_TRUNC 02000
+#endif
+#ifndef O_EXCL
+#define O_EXCL 0
+#endif
+
+/* <sys/stat.h> */
+#ifndef S_IRUSR
+#	ifdef S_IREAD
+#		define S_IRUSR S_IREAD
+#	else
+#		define S_IRUSR 0400
+#	endif
+#	ifdef S_IWRITE
+#		define S_IWUSR S_IWRITE
+#	else
+#		define S_IWUSR (S_IRUSR/2)
+#	endif
+#endif
+#ifndef S_IRGRP
+#	if has_getuid
+#		define S_IRGRP (S_IRUSR / 0010)
+#		define S_IWGRP (S_IWUSR / 0010)
+#		define S_IROTH (S_IRUSR / 0100)
+#		define S_IWOTH (S_IWUSR / 0100)
+#	else
+		/* single user OS -- not Posix or Unix */
+#		define S_IRGRP 0
+#		define S_IWGRP 0
+#		define S_IROTH 0
+#		define S_IWOTH 0
+#	endif
+#endif
+#ifndef S_ISREG
+#define S_ISREG(n) (((n) & S_IFMT) == S_IFREG)
+#endif
+
+/* <sys/wait.h> */
+#ifndef WEXITSTATUS
+#define WEXITSTATUS(stat_val) ((unsigned)(stat_val) >> 8)
+#undef WIFEXITED /* Avoid 4.3BSD incompatibility with Posix.  */
+#endif
+#ifndef WIFEXITED
+#define WIFEXITED(stat_val) (((stat_val)  &  0377) == 0)
+#endif
+#ifndef WTERMSIG
+#define WTERMSIG(stat_val) ((stat_val) & 0177)
+#undef WIFSIGNALED /* Avoid 4.3BSD incompatibility with Posix.  */
+#endif
+#ifndef WIFSIGNALED
+#define WIFSIGNALED(stat_val) ((unsigned)(stat_val) - 1  <  0377)
+#endif
+
+/* <unistd.h> */
+char *getlogin P((void));
+#ifndef STDIN_FILENO
+#	define STDIN_FILENO 0
+#	define STDOUT_FILENO 1
+#	define STDERR_FILENO 2
+#endif
+#if has_fork && !has_vfork
+#	undef vfork
+#	define vfork fork
+#endif
+#if has_getcwd || !has_getwd
+	char *getcwd P((char*,size_t));
+#else
+	char *getwd P((char*));
+#endif
+#if has_setuid && !has_seteuid
+#	undef seteuid
+#	define seteuid setuid
+#endif
+#if has_spawn
+#	if ALL_ABSOLUTE
+#		define spawn_RCS spawnv
+#	else
+#		define spawn_RCS spawnvp
+#	endif
+#else
+#	if ALL_ABSOLUTE
+#		define exec_RCS execv
+#	else
+#		define exec_RCS execvp
+#	endif
+#endif
+
+/* utime.h */
+#if !has_utimbuf
+	struct utimbuf { time_t actime, modtime; };
+#endif
+
+
+/* Standard C library */
+
+/* <stdio.h> */
+#ifndef L_tmpnam
+#define L_tmpnam 32 /* power of 2 > sizeof("/usr/tmp/xxxxxxxxxxxxxxx") */
+#endif
+#ifndef SEEK_SET
+#define SEEK_SET 0
+#endif
+#ifndef SEEK_CUR
+#define SEEK_CUR 1
+#endif
+#if has_mktemp
+	char *mktemp P((char*)); /* traditional */
+#else
+	char *tmpnam P((char*));
+#endif
+
+/* <stdlib.h> */
+char *getenv P((char const*));
+void _exit P((int)) exiting;
+void exit P((int)) exiting;
+malloc_type malloc P((size_t));
+malloc_type realloc P((malloc_type,size_t));
+#ifndef EXIT_FAILURE
+#define EXIT_FAILURE 1
+#endif
+#ifndef EXIT_SUCCESS
+#define EXIT_SUCCESS 0
+#endif
+
+/* <string.h> */
+char *strcpy P((char*,char const*));
+char *strchr P((char const*,int));
+char *strrchr P((char const*,int));
+void *memcpy P((void*,void const*,size_t));
+#if has_memmove
+	void *memmove P((void*,void const*,size_t));
+#endif
+
+/* <time.h> */
+time_t time P((time_t*));
diff --git a/gnu/usr.bin/rcs/lib/maketime.c b/gnu/usr.bin/rcs/lib/maketime.c
new file mode 100644
index 0000000000000..0f83bf5690d69
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/maketime.c
@@ -0,0 +1,344 @@
+/* Convert struct partime into time_t.  */
+
+/* Copyright 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#if has_conf_h
+#	include "conf.h"
+#else
+#	ifdef __STDC__
+#		define P(x) x
+#	else
+#		define const
+#		define P(x) ()
+#	endif
+#	include <stdlib.h>
+#	include <time.h>
+#endif
+
+#include "partime.h"
+#include "maketime.h"
+
+char const maketId[]
+  = "$FreeBSD$";
+
+static int isleap P((int));
+static int month_days P((struct tm const*));
+static time_t maketime P((struct partime const*,time_t));
+
+/*
+* For maximum portability, use only localtime and gmtime.
+* Make no assumptions about the time_t epoch or the range of time_t values.
+* Avoid mktime because it's not universal and because there's no easy,
+* portable way for mktime to yield the inverse of gmtime.
+*/
+
+#define TM_YEAR_ORIGIN 1900
+
+	static int
+isleap(y)
+	int y;
+{
+	return (y&3) == 0  &&  (y%100 != 0 || y%400 == 0);
+}
+
+static int const month_yday[] = {
+	/* days in year before start of months 0-12 */
+	0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365
+};
+
+/* Yield the number of days in TM's month.  */
+	static int
+month_days(tm)
+	struct tm const *tm;
+{
+	int m = tm->tm_mon;
+	return month_yday[m+1] - month_yday[m]
+		+ (m==1 && isleap(tm->tm_year + TM_YEAR_ORIGIN));
+}
+
+/*
+* Convert UNIXTIME to struct tm form.
+* Use gmtime if available and if !LOCALZONE, localtime otherwise.
+*/
+	struct tm *
+time2tm(unixtime, localzone)
+	time_t unixtime;
+	int localzone;
+{
+	struct tm *tm;
+#	if TZ_must_be_set
+		static char const *TZ;
+		if (!TZ  &&  !(TZ = getenv("TZ")))
+			faterror("The TZ environment variable is not set; please set it to your timezone");
+#	endif
+	if (localzone  ||  !(tm = gmtime(&unixtime)))
+		tm = localtime(&unixtime);
+	return tm;
+}
+
+/* Yield A - B, measured in seconds.  */
+	time_t
+difftm(a, b)
+	struct tm const *a, *b;
+{
+	int ay = a->tm_year + (TM_YEAR_ORIGIN - 1);
+	int by = b->tm_year + (TM_YEAR_ORIGIN - 1);
+	int difference_in_day_of_year = a->tm_yday - b->tm_yday;
+	int intervening_leap_days = (
+		((ay >> 2) - (by >> 2))
+		- (ay/100 - by/100)
+		+ ((ay/100 >> 2) - (by/100 >> 2))
+	);
+	time_t difference_in_years = ay - by;
+	time_t difference_in_days = (
+		difference_in_years*365
+		+ (intervening_leap_days + difference_in_day_of_year)
+	);
+	return
+		(
+			(
+				24*difference_in_days
+				+ (a->tm_hour - b->tm_hour)
+			)*60 + (a->tm_min - b->tm_min)
+		)*60 + (a->tm_sec - b->tm_sec);
+}
+
+/*
+* Adjust time T by adding SECONDS.  SECONDS must be at most 24 hours' worth.
+* Adjust only T's year, mon, mday, hour, min and sec members;
+* plus adjust wday if it is defined.
+*/
+	void
+adjzone(t, seconds)
+	register struct tm *t;
+	long seconds;
+{
+	/*
+	* This code can be off by a second if SECONDS is not a multiple of 60,
+	* if T is local time, and if a leap second happens during this minute.
+	* But this bug has never occurred, and most likely will not ever occur.
+	* Liberia, the last country for which SECONDS % 60 was nonzero,
+	* switched to UTC in May 1972; the first leap second was in June 1972.
+	*/
+	int leap_second = t->tm_sec == 60;
+	long sec = seconds + (t->tm_sec - leap_second);
+	if (sec < 0) {
+	    if ((t->tm_min -= (59-sec)/60) < 0) {
+		if ((t->tm_hour -= (59-t->tm_min)/60) < 0) {
+		    t->tm_hour += 24;
+		    if (TM_DEFINED(t->tm_wday)  &&  --t->tm_wday < 0)
+			t->tm_wday = 6;
+		    if (--t->tm_mday <= 0) {
+			if (--t->tm_mon < 0) {
+			    --t->tm_year;
+			    t->tm_mon = 11;
+			}
+			t->tm_mday = month_days(t);
+		    }
+		}
+		t->tm_min += 24 * 60;
+	    }
+	    sec += 24L * 60 * 60;
+	} else
+	    if (60 <= (t->tm_min += sec/60))
+		if (24 <= (t->tm_hour += t->tm_min/60)) {
+		    t->tm_hour -= 24;
+		    if (TM_DEFINED(t->tm_wday)  &&  ++t->tm_wday == 7)
+			t->tm_wday = 0;
+		    if (month_days(t) < ++t->tm_mday) {
+			if (11 < ++t->tm_mon) {
+			    ++t->tm_year;
+			    t->tm_mon = 0;
+			}
+			t->tm_mday = 1;
+		    }
+		}
+	t->tm_min %= 60;
+	t->tm_sec = (int) (sec%60) + leap_second;
+}
+
+/*
+* Convert TM to time_t, using localtime if LOCALZONE and gmtime otherwise.
+* Use only TM's year, mon, mday, hour, min, and sec members.
+* Ignore TM's old tm_yday and tm_wday, but fill in their correct values.
+* Yield -1 on failure (e.g. a member out of range).
+* Posix 1003.1-1990 doesn't allow leap seconds, but some implementations
+* have them anyway, so allow them if localtime/gmtime does.
+*/
+	time_t
+tm2time(tm, localzone)
+	struct tm *tm;
+	int localzone;
+{
+	/* Cache the most recent t,tm pairs; 1 for gmtime, 1 for localtime.  */
+	static time_t t_cache[2];
+	static struct tm tm_cache[2];
+
+	time_t d, gt;
+	struct tm const *gtm;
+	/*
+	* The maximum number of iterations should be enough to handle any
+	* combinations of leap seconds, time zone rule changes, and solar time.
+	* 4 is probably enough; we use a bigger number just to be safe.
+	*/
+	int remaining_tries = 8;
+
+	/* Avoid subscript errors.  */
+	if (12 <= (unsigned)tm->tm_mon)
+	    return -1;
+
+	tm->tm_yday = month_yday[tm->tm_mon] + tm->tm_mday
+		-  (tm->tm_mon<2  ||  ! isleap(tm->tm_year + TM_YEAR_ORIGIN));
+
+	/* Make a first guess.  */
+	gt = t_cache[localzone];
+	gtm = gt ? &tm_cache[localzone] : time2tm(gt,localzone);
+
+	/* Repeatedly use the error from the guess to improve the guess.  */
+	while ((d = difftm(tm, gtm)) != 0) {
+		if (--remaining_tries == 0)
+			return -1;
+		gt += d;
+		gtm = time2tm(gt,localzone);
+	}
+	t_cache[localzone] = gt;
+	tm_cache[localzone] = *gtm;
+
+	/*
+	* Check that the guess actually matches;
+	* overflow can cause difftm to yield 0 even on differing times,
+	* or tm may have members out of range (e.g. bad leap seconds).
+	*/
+	if (   (tm->tm_year ^ gtm->tm_year)
+	    |  (tm->tm_mon  ^ gtm->tm_mon)
+	    |  (tm->tm_mday ^ gtm->tm_mday)
+	    |  (tm->tm_hour ^ gtm->tm_hour)
+	    |  (tm->tm_min  ^ gtm->tm_min)
+	    |  (tm->tm_sec  ^ gtm->tm_sec))
+		return -1;
+
+	tm->tm_wday = gtm->tm_wday;
+	return gt;
+}
+
+/*
+* Check *PT and convert it to time_t.
+* If it is incompletely specified, use DEFAULT_TIME to fill it out.
+* Use localtime if PT->zone is the special value TM_LOCAL_ZONE.
+* Yield -1 on failure.
+* ISO 8601 day-of-year and week numbers are not yet supported.
+*/
+	static time_t
+maketime(pt, default_time)
+	struct partime const *pt;
+	time_t default_time;
+{
+	int localzone, wday;
+	struct tm tm;
+	struct tm *tm0 = 0;
+	time_t r;
+
+	tm0 = 0; /* Keep gcc -Wall happy.  */
+	localzone = pt->zone==TM_LOCAL_ZONE;
+
+	tm = pt->tm;
+
+	if (TM_DEFINED(pt->ymodulus) || !TM_DEFINED(tm.tm_year)) {
+	    /* Get tm corresponding to current time.  */
+	    tm0 = time2tm(default_time, localzone);
+	    if (!localzone)
+		adjzone(tm0, pt->zone);
+	}
+
+	if (TM_DEFINED(pt->ymodulus))
+	    tm.tm_year +=
+		(tm0->tm_year + TM_YEAR_ORIGIN)/pt->ymodulus * pt->ymodulus;
+	else if (!TM_DEFINED(tm.tm_year)) {
+	    /* Set default year, month, day from current time.  */
+	    tm.tm_year = tm0->tm_year + TM_YEAR_ORIGIN;
+	    if (!TM_DEFINED(tm.tm_mon)) {
+		tm.tm_mon = tm0->tm_mon;
+		if (!TM_DEFINED(tm.tm_mday))
+		    tm.tm_mday = tm0->tm_mday;
+	    }
+	}
+
+	/* Convert from partime year (Gregorian) to Posix year.  */
+	tm.tm_year -= TM_YEAR_ORIGIN;
+
+	/* Set remaining default fields to be their minimum values.  */
+	if (!TM_DEFINED(tm.tm_mon)) tm.tm_mon = 0;
+	if (!TM_DEFINED(tm.tm_mday)) tm.tm_mday = 1;
+	if (!TM_DEFINED(tm.tm_hour)) tm.tm_hour = 0;
+	if (!TM_DEFINED(tm.tm_min)) tm.tm_min = 0;
+	if (!TM_DEFINED(tm.tm_sec)) tm.tm_sec = 0;
+
+	if (!localzone)
+	    adjzone(&tm, -pt->zone);
+	wday = tm.tm_wday;
+
+	/* Convert and fill in the rest of the tm.  */
+	r = tm2time(&tm, localzone);
+
+	/* Check weekday.  */
+	if (r != -1  &&  TM_DEFINED(wday)  &&  wday != tm.tm_wday)
+		return -1;
+
+	return r;
+}
+
+/* Parse a free-format date in SOURCE, yielding a Unix format time.  */
+	time_t
+str2time(source, default_time, default_zone)
+	char const *source;
+	time_t default_time;
+	long default_zone;
+{
+	struct partime pt;
+
+	if (*partime(source, &pt))
+	    return -1;
+	if (pt.zone == TM_UNDEFINED_ZONE)
+	    pt.zone = default_zone;
+	return maketime(&pt, default_time);
+}
+
+#if TEST
+#include <stdio.h>
+	int
+main(argc, argv) int argc; char **argv;
+{
+	time_t default_time = time((time_t *)0);
+	long default_zone = argv[1] ? atol(argv[1]) : 0;
+	char buf[1000];
+	while (fgets(buf, 1000, stdin)) {
+		time_t t = str2time(buf, default_time, default_zone);
+		printf("%s", asctime(gmtime(&t)));
+	}
+	return 0;
+}
+#endif
diff --git a/gnu/usr.bin/rcs/lib/maketime.h b/gnu/usr.bin/rcs/lib/maketime.h
new file mode 100644
index 0000000000000..fbe12562051df
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/maketime.h
@@ -0,0 +1,39 @@
+/* Yield time_t from struct partime yielded by partime.  */
+
+/* Copyright 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#if defined(__STDC__) || has_prototypes
+#	define __MAKETIME_P(x) x
+#else
+#	define __MAKETIME_P(x) ()
+#endif
+
+struct tm *time2tm __MAKETIME_P((time_t,int));
+time_t difftm __MAKETIME_P((struct tm const *, struct tm const *));
+time_t str2time __MAKETIME_P((char const *, time_t, long));
+time_t tm2time __MAKETIME_P((struct tm *, int));
+void adjzone __MAKETIME_P((struct tm *, long));
diff --git a/gnu/usr.bin/rcs/lib/merger.c b/gnu/usr.bin/rcs/lib/merger.c
new file mode 100644
index 0000000000000..8f1d610d5f564
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/merger.c
@@ -0,0 +1,148 @@
+/* three-way file merge internals */
+
+/* Copyright 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#include "rcsbase.h"
+
+libId(mergerId, "$FreeBSD$")
+
+	static char const *normalize_arg P((char const*,char**));
+	static char const *
+normalize_arg(s, b)
+	char const *s;
+	char **b;
+/*
+ * If S looks like an option, prepend ./ to it.  Yield the result.
+ * Set *B to the address of any storage that was allocated.
+ */
+{
+	char *t;
+	if (*s == '-') {
+		*b = t = testalloc(strlen(s) + 3);
+		VOID sprintf(t, ".%c%s", SLASH, s);
+		return t;
+	} else {
+		*b = 0;
+		return s;
+	}
+}
+
+	int
+merge(tostdout, edarg, label, argv)
+	int tostdout;
+	char const *edarg;
+	char const *const label[3];
+	char const *const argv[3];
+/*
+ * Do `merge [-p] EDARG -L l0 -L l1 -L l2 a0 a1 a2',
+ * where TOSTDOUT specifies whether -p is present,
+ * EDARG gives the editing type (e.g. "-A", or null for the default),
+ * LABEL gives l0, l1 and l2, and ARGV gives a0, a1 and a2.
+ * Yield DIFF_SUCCESS or DIFF_FAILURE.
+ */
+{
+	register int i;
+	FILE *f;
+	RILE *rt;
+	char const *a[3], *t;
+	char *b[3];
+	int s;
+#if !DIFF3_BIN
+	char const *d[2];
+#endif
+
+	for (i=3; 0<=--i; )
+		a[i] = normalize_arg(argv[i], &b[i]);
+
+	if (!edarg)
+		edarg = "-E";
+
+#if DIFF3_BIN
+	t = 0;
+	if (!tostdout)
+		t = maketemp(0);
+	s = run(
+		-1, t,
+		DIFF3, edarg, "-am",
+		"-L", label[0],
+		"-L", label[1],
+		"-L", label[2],
+		a[0], a[1], a[2], (char*)0
+	);
+	switch (s) {
+		case DIFF_SUCCESS:
+			break;
+		case DIFF_FAILURE:
+			warn("conflicts during merge");
+			break;
+		default:
+			exiterr();
+	}
+	if (t) {
+		if (!(f = fopenSafer(argv[0], "w")))
+			efaterror(argv[0]);
+		if (!(rt = Iopen(t, "r", (struct stat*)0)))
+			efaterror(t);
+		fastcopy(rt, f);
+		Ifclose(rt);
+		Ofclose(f);
+	}
+#else
+	for (i=0; i<2; i++)
+		switch (run(
+			-1, d[i]=maketemp(i),
+			DIFF, a[i], a[2], (char*)0
+		)) {
+			case DIFF_FAILURE: case DIFF_SUCCESS: break;
+			default: faterror("diff failed");
+		}
+	t = maketemp(2);
+	s = run(
+		-1, t,
+		DIFF3, edarg, d[0], d[1], a[0], a[1], a[2],
+		label[0], label[2], (char*)0
+	);
+	if (s != DIFF_SUCCESS) {
+		s = DIFF_FAILURE;
+		warn("overlaps or other problems during merge");
+	}
+	if (!(f = fopenSafer(t, "a+")))
+		efaterror(t);
+	aputs(tostdout ? "1,$p\n" : "w\n",  f);
+	Orewind(f);
+	aflush(f);
+	if (run(fileno(f), (char*)0, ED, "-", a[0], (char*)0))
+		exiterr();
+	Ofclose(f);
+#endif
+
+	tempunlink();
+	for (i=3; 0<=--i; )
+		if (b[i])
+			tfree(b[i]);
+	return s;
+}
diff --git a/gnu/usr.bin/rcs/lib/partime.c b/gnu/usr.bin/rcs/lib/partime.c
new file mode 100644
index 0000000000000..05b010854950f
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/partime.c
@@ -0,0 +1,701 @@
+/* Parse a string, yielding a struct partime that describes it.  */
+
+/* Copyright 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#if has_conf_h
+#	include "conf.h"
+#else
+#	ifdef __STDC__
+#		define P(x) x
+#	else
+#		define const
+#		define P(x) ()
+#	endif
+#	include <limits.h>
+#	include <time.h>
+#endif
+
+#include <ctype.h>
+#undef isdigit
+#define isdigit(c) (((unsigned)(c)-'0') <= 9) /* faster than stock */
+
+#include "partime.h"
+
+char const partimeId[]
+  = "$FreeBSD$";
+
+
+/* Lookup tables for names of months, weekdays, time zones.  */
+
+#define NAME_LENGTH_MAXIMUM 4
+
+struct name_val {
+	char name[NAME_LENGTH_MAXIMUM];
+	int val;
+};
+
+
+static char const *parse_decimal P((char const*,int,int,int,int,int*,int*));
+static char const *parse_fixed P((char const*,int,int*));
+static char const *parse_pattern_letter P((char const*,int,struct partime*));
+static char const *parse_prefix P((char const*,struct partime*,int*));
+static char const *parse_ranged P((char const*,int,int,int,int*));
+static int lookup P((char const*,struct name_val const[]));
+static int merge_partime P((struct partime*, struct partime const*));
+static void undefine P((struct partime*));
+
+
+static struct name_val const month_names[] = {
+	{"jan",0}, {"feb",1}, {"mar",2}, {"apr",3}, {"may",4}, {"jun",5},
+	{"jul",6}, {"aug",7}, {"sep",8}, {"oct",9}, {"nov",10}, {"dec",11},
+	{"", TM_UNDEFINED}
+};
+
+static struct name_val const weekday_names[] = {
+	{"sun",0}, {"mon",1}, {"tue",2}, {"wed",3}, {"thu",4}, {"fri",5}, {"sat",6},
+	{"", TM_UNDEFINED}
+};
+
+#define hr60nonnegative(t)  ((t)/100 * 60  +  (t)%100)
+#define hr60(t)  ((t)<0 ? -hr60nonnegative(-(t)) : hr60nonnegative(t))
+#define zs(t,s)  {s, hr60(t)}
+#define zd(t,s,d)  zs(t, s),  zs((t)+100, d)
+
+static struct name_val const zone_names[] = {
+	zs(-1000, "hst"),		/* Hawaii */
+	zd(-1000,"hast","hadt"),/* Hawaii-Aleutian */
+	zd(- 900,"akst","akdt"),/* Alaska */
+	zd(- 800, "pst", "pdt"),/* Pacific */
+	zd(- 700, "mst", "mdt"),/* Mountain */
+	zd(- 600, "cst", "cdt"),/* Central */
+	zd(- 500, "est", "edt"),/* Eastern */
+	zd(- 400, "ast", "adt"),/* Atlantic */
+	zd(- 330, "nst", "ndt"),/* Newfoundland */
+	zs(  000, "utc"),		/* Coordinated Universal */
+	zs(  000, "cut"),		/* " */
+	zs(  000,  "ut"),		/* Universal */
+	zs(  000,   "z"),		/* Zulu (required by ISO 8601) */
+	zd(  000, "gmt", "bst"),/* Greenwich Mean, British Summer */
+	zs(  000, "wet"),		/* Western Europe */
+	zs(  100, "met"),		/* Middle Europe */
+	zs(  100, "cet"),		/* Central Europe */
+	zs(  200, "eet"),		/* Eastern Europe */
+	zs(  530, "ist"),		/* India */
+	zd(  900, "jst", "jdt"),/* Japan */
+	zd(  900, "kst", "kdt"),/* Korea */
+	zd( 1200,"nzst","nzdt"),/* New Zealand */
+	{ "lt", 1 },
+#if 0
+	/* The following names are duplicates or are not well attested.  */
+	zs(-1100, "sst"),		/* Samoa */
+	zs(-1000, "tht"),		/* Tahiti */
+	zs(- 930, "mqt"),		/* Marquesas */
+	zs(- 900, "gbt"),		/* Gambier */
+	zd(- 900, "yst", "ydt"),/* Yukon - name is no longer used */
+	zs(- 830, "pit"),		/* Pitcairn */
+	zd(- 500, "cst", "cdt"),/* Cuba */
+	zd(- 500, "ast", "adt"),/* Acre */
+	zd(- 400, "wst", "wdt"),/* Western Brazil */
+	zd(- 400, "ast", "adt"),/* Andes */
+	zd(- 400, "cst", "cdt"),/* Chile */
+	zs(- 300, "wgt"),		/* Western Greenland */
+	zd(- 300, "est", "edt"),/* Eastern South America */
+	zs(- 300, "mgt"),		/* Middle Greenland */
+	zd(- 200, "fst", "fdt"),/* Fernando de Noronha */
+	zs(- 100, "egt"),		/* Eastern Greenland */
+	zs(- 100, "aat"),		/* Atlantic Africa */
+	zs(- 100, "act"),		/* Azores and Canaries */
+	zs(  000, "wat"),		/* West Africa */
+	zs(  100, "cat"),		/* Central Africa */
+	zd(  100, "mez","mesz"),/* Mittel-Europaeische Zeit */
+	zs(  200, "sat"),		/* South Africa */
+	zd(  200, "ist", "idt"),/* Israel */
+	zs(  300, "eat"),		/* East Africa */
+	zd(  300, "ast", "adt"),/* Arabia */
+	zd(  300, "msk", "msd"),/* Moscow */
+	zd(  330, "ist", "idt"),/* Iran */
+	zs(  400, "gst"),		/* Gulf */
+	zs(  400, "smt"),		/* Seychelles & Mascarene */
+	zd(  400, "esk", "esd"),/* Yekaterinburg */
+	zd(  400, "bsk", "bsd"),/* Baku */
+	zs(  430, "aft"),		/* Afghanistan */
+	zd(  500, "osk", "osd"),/* Omsk */
+	zs(  500, "pkt"),		/* Pakistan */
+	zd(  500, "tsk", "tsd"),/* Tashkent */
+	zs(  545, "npt"),		/* Nepal */
+	zs(  600, "bgt"),		/* Bangladesh */
+	zd(  600, "nsk", "nsd"),/* Novosibirsk */
+	zs(  630, "bmt"),		/* Burma */
+	zs(  630, "cct"),		/* Cocos */
+	zs(  700, "ict"),		/* Indochina */
+	zs(  700, "jvt"),		/* Java */
+	zd(  700, "isk", "isd"),/* Irkutsk */
+	zs(  800, "hkt"),		/* Hong Kong */
+	zs(  800, "pst"),		/* Philippines */
+	zs(  800, "sgt"),		/* Singapore */
+	zd(  800, "cst", "cdt"),/* China */
+	zd(  800, "ust", "udt"),/* Ulan Bator */
+	zd(  800, "wst", "wst"),/* Western Australia */
+	zd(  800, "ysk", "ysd"),/* Yakutsk */
+	zs(  900, "blt"),		/* Belau */
+	zs(  900, "mlt"),		/* Moluccas */
+	zd(  900, "vsk", "vsd"),/* Vladivostok */
+	zd(  930, "cst", "cst"),/* Central Australia */
+	zs( 1000, "gst"),		/* Guam */
+	zd( 1000, "gsk", "gsd"),/* Magadan */
+	zd( 1000, "est", "est"),/* Eastern Australia */
+	zd( 1100,"lhst","lhst"),/* Lord Howe */
+	zd( 1100, "psk", "psd"),/* Petropavlovsk-Kamchatski */
+	zs( 1100,"ncst"),		/* New Caledonia */
+	zs( 1130,"nrft"),		/* Norfolk */
+	zd( 1200, "ask", "asd"),/* Anadyr */
+	zs( 1245,"nz-chat"),	/* Chatham */
+	zs( 1300, "tgt"),		/* Tongatapu */
+#endif
+	{"", -1}
+};
+
+	static int
+lookup (s, table)
+	char const *s;
+	struct name_val const table[];
+/* Look for a prefix of S in TABLE, returning val for first matching entry.  */
+{
+	int j;
+	char buf[NAME_LENGTH_MAXIMUM];
+
+	for (j = 0;  j < NAME_LENGTH_MAXIMUM;  j++) {
+		unsigned char c = *s++;
+		buf[j] = isupper (c) ? tolower (c) : c;
+		if (!isalpha (c))
+			break;
+	}
+	for (;  table[0].name[0];  table++)
+		for (j = 0;  buf[j] == table[0].name[j];  )
+			if (++j == NAME_LENGTH_MAXIMUM  ||  !table[0].name[j])
+				goto done;
+  done:
+	return table[0].val;
+}
+
+
+	static void
+undefine (t) struct partime *t;
+/* Set *T to ``undefined'' values.  */
+{
+	t->tm.tm_sec = t->tm.tm_min = t->tm.tm_hour = t->tm.tm_mday = t->tm.tm_mon
+		= t->tm.tm_year = t->tm.tm_wday = t->tm.tm_yday
+		= t->ymodulus = t->yweek
+		= TM_UNDEFINED;
+	t->zone = TM_UNDEFINED_ZONE;
+}
+
+/*
+* Array of patterns to look for in a date string.
+* Order is important: we look for the first matching pattern
+* whose values do not contradict values that we already know about.
+* See `parse_pattern_letter' below for the meaning of the pattern codes.
+*/
+static char const * const patterns[] = {
+	/*
+	* These traditional patterns must come first,
+	* to prevent an ISO 8601 format from misinterpreting their prefixes.
+	*/
+	"E_n_y", "x", /* RFC 822 */
+	"E_n", "n_E", "n", "t:m:s_A", "t:m_A", "t_A", /* traditional */
+	"y/N/D$", /* traditional RCS */
+
+	/* ISO 8601:1988 formats, generalized a bit.  */
+	"y-N-D$", "4ND$", "Y-N$",
+	"RND$", "-R=N$", "-R$", "--N=D$", "N=DT",
+	"--N$", "---D$", "DT",
+	"Y-d$", "4d$", "R=d$", "-d$", "dT",
+	"y-W-X", "yWX", "y=W",
+	"-r-W-X", "r-W-XT", "-rWX", "rWXT", "-W=X", "W=XT", "-W",
+	"-w-X", "w-XT", "---X$", "XT", "4$",
+	"T",
+	"h:m:s$", "hms$", "h:m$", "hm$", "h$", "-m:s$", "-ms$", "-m$", "--s$",
+	"Y", "Z",
+
+	0
+};
+
+	static char const *
+parse_prefix (str, t, pi) char const *str; struct partime *t; int *pi;
+/*
+* Parse an initial prefix of STR, setting *T accordingly.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+* Start with pattern *PI; if success, set *PI to the next pattern to try.
+* Set *PI to -1 if we know there are no more patterns to try;
+* if *PI is initially negative, give up immediately.
+*/
+{
+	int i = *pi;
+	char const *pat;
+	unsigned char c;
+
+	if (i < 0)
+		return 0;
+
+	/* Remove initial noise.  */
+	while (!isalnum (c = *str)  &&  c != '-'  &&  c != '+') {
+		if (!c) {
+			undefine (t);
+			*pi = -1;
+			return str;
+		}
+		str++;
+	}
+
+	/* Try a pattern until one succeeds.  */
+	while ((pat = patterns[i++]) != 0) {
+		char const *s = str;
+		undefine (t);
+		do {
+			if (!(c = *pat++)) {
+				*pi = i;
+				return s;
+			}
+		} while ((s = parse_pattern_letter (s, c, t)) != 0);
+	}
+
+	return 0;
+}
+
+	static char const *
+parse_fixed (s, digits, res) char const *s; int digits, *res;
+/*
+* Parse an initial prefix of S of length DIGITS; it must be a number.
+* Store the parsed number into *RES.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+*/
+{
+	int n = 0;
+	char const *lim = s + digits;
+	while (s < lim) {
+		unsigned d = *s++ - '0';
+		if (9 < d)
+			return 0;
+		n = 10*n + d;
+	}
+	*res = n;
+	return s;
+}
+
+	static char const *
+parse_ranged (s, digits, lo, hi, res) char const *s; int digits, lo, hi, *res;
+/*
+* Parse an initial prefix of S of length DIGITS;
+* it must be a number in the range LO through HI.
+* Store the parsed number into *RES.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+*/
+{
+	s = parse_fixed (s, digits, res);
+	return  s && lo<=*res && *res<=hi  ?  s  :  0;
+}
+
+	static char const *
+parse_decimal (s, digits, lo, hi, resolution, res, fres)
+	char const *s;
+	int digits, lo, hi, resolution, *res, *fres;
+/*
+* Parse an initial prefix of S of length DIGITS;
+* it must be a number in the range LO through HI
+* and it may be followed by a fraction that is to be computed using RESOLUTION.
+* Store the parsed number into *RES; store the fraction times RESOLUTION,
+* rounded to the nearest integer, into *FRES.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+*/
+{
+	s = parse_fixed (s, digits, res);
+	if (s && lo<=*res && *res<=hi) {
+		int f = 0;
+		if ((s[0]==',' || s[0]=='.')  &&  isdigit ((unsigned char) s[1])) {
+			char const *s1 = ++s;
+			int num10 = 0, denom10 = 10, product;
+			while (isdigit ((unsigned char) *++s))
+				denom10 *= 10;
+			s = parse_fixed (s1, s - s1, &num10);
+			product = num10*resolution;
+			f = (product + (denom10>>1)) / denom10;
+			f -= f & (product%denom10 == denom10>>1); /* round to even */
+			if (f < 0  ||  product/resolution != num10)
+				return 0; /* overflow */
+		}
+		*fres = f;
+		return s;
+	}
+	return 0;
+}
+
+	char *
+parzone (s, zone) char const *s; long *zone;
+/*
+* Parse an initial prefix of S; it must denote a time zone.
+* Set *ZONE to the number of seconds east of GMT,
+* or to TM_LOCAL_ZONE if it is the local time zone.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+*/
+{
+	char sign;
+	int hh, mm, ss;
+	int minutesEastOfUTC;
+	long offset, z;
+
+	/*
+	* The formats are LT, n, n DST, nDST, no, o
+	* where n is a time zone name
+	* and o is a time zone offset of the form [-+]hh[:mm[:ss]].
+	*/
+	switch (*s) {
+		case '-': case '+':
+			z = 0;
+			break;
+
+		default:
+			minutesEastOfUTC = lookup (s, zone_names);
+			if (minutesEastOfUTC == -1)
+				return 0;
+
+			/* Don't bother to check rest of spelling.  */
+			while (isalpha ((unsigned char) *s))
+				s++;
+
+			/* Don't modify LT.  */
+			if (minutesEastOfUTC == 1) {
+				*zone = TM_LOCAL_ZONE;
+				return (char *) s;
+			}
+
+			z = minutesEastOfUTC * 60L;
+
+			/* Look for trailing " DST".  */
+			if (
+				(s[-1]=='T' || s[-1]=='t') &&
+				(s[-2]=='S' || s[-2]=='s') &&
+				(s[-3]=='D' || s[-3]=='t')
+			)
+				goto trailing_dst;
+			while (isspace ((unsigned char) *s))
+				s++;
+			if (
+				(s[0]=='D' || s[0]=='d') &&
+				(s[1]=='S' || s[1]=='s') &&
+				(s[2]=='T' || s[2]=='t')
+			) {
+				s += 3;
+			  trailing_dst:
+				*zone = z + 60*60;
+				return (char *) s;
+			}
+
+			switch (*s) {
+				case '-': case '+': break;
+				default: return (char *) s;
+			}
+	}
+	sign = *s++;
+
+	if (!(s = parse_ranged (s, 2, 0, 23, &hh)))
+		return 0;
+	mm = ss = 0;
+	if (*s == ':')
+		s++;
+	if (isdigit ((unsigned char) *s)) {
+		if (!(s = parse_ranged (s, 2, 0, 59, &mm)))
+			return 0;
+		if (*s==':' && s[-3]==':' && isdigit ((unsigned char) s[1])) {
+			if (!(s = parse_ranged (s + 1, 2, 0, 59, &ss)))
+				return 0;
+		}
+	}
+	if (isdigit ((unsigned char) *s))
+		return 0;
+	offset = (hh*60 + mm)*60L + ss;
+	*zone = z + (sign=='-' ? -offset : offset);
+	/*
+	* ?? Are fractions allowed here?
+	* If so, they're not implemented.
+	*/
+	return (char *) s;
+}
+
+	static char const *
+parse_pattern_letter (s, c, t) char const *s; int c; struct partime *t;
+/*
+* Parse an initial prefix of S, matching the pattern whose code is C.
+* Set *T accordingly.
+* Return the first character after the prefix, or 0 if it couldn't be parsed.
+*/
+{
+	switch (c) {
+		case '$': /* The next character must be a non-digit.  */
+			if (isdigit ((unsigned char) *s))
+				return 0;
+			break;
+
+		case '-': case '/': case ':':
+			/* These characters stand for themselves.  */
+			if (*s++ != c)
+				return 0;
+			break;
+
+		case '4': /* 4-digit year */
+			s = parse_fixed (s, 4, &t->tm.tm_year);
+			break;
+
+		case '=': /* optional '-' */
+			s  +=  *s == '-';
+			break;
+
+		case 'A': /* AM or PM */
+			/*
+			* This matches the regular expression [AaPp][Mm]?.
+			* It must not be followed by a letter or digit;
+			* otherwise it would match prefixes of strings like "PST".
+			*/
+			switch (*s++) {
+				case 'A': case 'a':
+					if (t->tm.tm_hour == 12)
+						t->tm.tm_hour = 0;
+					break;
+
+				case 'P': case 'p':
+					if (t->tm.tm_hour != 12)
+						t->tm.tm_hour += 12;
+					break;
+
+				default: return 0;
+			}
+			switch (*s) {
+				case 'M': case 'm': s++; break;
+			}
+			if (isalnum (*s))
+				return 0;
+			break;
+
+		case 'D': /* day of month [01-31] */
+			s = parse_ranged (s, 2, 1, 31, &t->tm.tm_mday);
+			break;
+
+		case 'd': /* day of year [001-366] */
+			s = parse_ranged (s, 3, 1, 366, &t->tm.tm_yday);
+			t->tm.tm_yday--;
+			break;
+
+		case 'E': /* extended day of month [1-9, 01-31] */
+			s = parse_ranged (s, (
+				isdigit ((unsigned char) s[0]) &&
+				isdigit ((unsigned char) s[1])
+			) + 1, 1, 31, &t->tm.tm_mday);
+			break;
+
+		case 'h': /* hour [00-23 followed by optional fraction] */
+			{
+				int frac;
+				s = parse_decimal (s, 2, 0, 23, 60*60, &t->tm.tm_hour, &frac);
+				t->tm.tm_min = frac / 60;
+				t->tm.tm_sec = frac % 60;
+			}
+			break;
+
+		case 'm': /* minute [00-59 followed by optional fraction] */
+			s = parse_decimal (s, 2, 0, 59, 60, &t->tm.tm_min, &t->tm.tm_sec);
+			break;
+
+		case 'n': /* month name [e.g. "Jan"] */
+			if (!TM_DEFINED (t->tm.tm_mon = lookup (s, month_names)))
+				return 0;
+			/* Don't bother to check rest of spelling.  */
+			while (isalpha ((unsigned char) *s))
+				s++;
+			break;
+
+		case 'N': /* month [01-12] */
+			s = parse_ranged (s, 2, 1, 12, &t->tm.tm_mon);
+			t->tm.tm_mon--;
+			break;
+
+		case 'r': /* year % 10 (remainder in origin-0 decade) [0-9] */
+			s = parse_fixed (s, 1, &t->tm.tm_year);
+			t->ymodulus = 10;
+			break;
+
+		case_R:
+		case 'R': /* year % 100 (remainder in origin-0 century) [00-99] */
+			s = parse_fixed (s, 2, &t->tm.tm_year);
+			t->ymodulus = 100;
+			break;
+
+		case 's': /* second [00-60 followed by optional fraction] */
+			{
+				int frac;
+				s = parse_decimal (s, 2, 0, 60, 1, &t->tm.tm_sec, &frac);
+				t->tm.tm_sec += frac;
+			}
+			break;
+
+		case 'T': /* 'T' or 't' */
+			switch (*s++) {
+				case 'T': case 't': break;
+				default: return 0;
+			}
+			break;
+
+		case 't': /* traditional hour [1-9 or 01-12] */
+			s = parse_ranged (s, (
+				isdigit ((unsigned char) s[0]) && isdigit ((unsigned char) s[1])
+			) + 1, 1, 12, &t->tm.tm_hour);
+			break;
+
+		case 'w': /* 'W' or 'w' only (stands for current week) */
+			switch (*s++) {
+				case 'W': case 'w': break;
+				default: return 0;
+			}
+			break;
+
+		case 'W': /* 'W' or 'w', followed by a week of year [00-53] */
+			switch (*s++) {
+				case 'W': case 'w': break;
+				default: return 0;
+			}
+			s = parse_ranged (s, 2, 0, 53, &t->yweek);
+			break;
+
+		case 'X': /* weekday (1=Mon ... 7=Sun) [1-7] */
+			s = parse_ranged (s, 1, 1, 7, &t->tm.tm_wday);
+			t->tm.tm_wday--;
+			break;
+
+		case 'x': /* weekday name [e.g. "Sun"] */
+			if (!TM_DEFINED (t->tm.tm_wday = lookup (s, weekday_names)))
+				return 0;
+			/* Don't bother to check rest of spelling.  */
+			while (isalpha ((unsigned char) *s))
+				s++;
+			break;
+
+		case 'y': /* either R or Y */
+			if (
+				isdigit ((unsigned char) s[0]) &&
+				isdigit ((unsigned char) s[1]) &&
+				!isdigit ((unsigned char) s[2])
+			)
+				goto case_R;
+			/* fall into */
+		case 'Y': /* year in full [4 or more digits] */
+			{
+				int len = 0;
+				while (isdigit ((unsigned char) s[len]))
+					len++;
+				if (len < 4)
+					return 0;
+				s = parse_fixed (s, len, &t->tm.tm_year);
+			}
+			break;
+
+		case 'Z': /* time zone */
+			s = parzone (s, &t->zone);
+			break;
+
+		case '_': /* possibly empty sequence of non-alphanumerics */
+			while (!isalnum (*s)  &&  *s)
+				s++;
+			break;
+
+		default: /* bad pattern */
+			return 0;
+	}
+	return s;
+}
+
+	static int
+merge_partime (t, u) struct partime *t; struct partime const *u;
+/*
+* If there is no conflict, merge into *T the additional information in *U
+* and return 0.  Otherwise do nothing and return -1.
+*/
+{
+#	define conflict(a,b) ((a) != (b)  &&  TM_DEFINED (a)  &&  TM_DEFINED (b))
+	if (
+		conflict (t->tm.tm_sec, u->tm.tm_sec) ||
+		conflict (t->tm.tm_min, u->tm.tm_min) ||
+		conflict (t->tm.tm_hour, u->tm.tm_hour) ||
+		conflict (t->tm.tm_mday, u->tm.tm_mday) ||
+		conflict (t->tm.tm_mon, u->tm.tm_mon) ||
+		conflict (t->tm.tm_year, u->tm.tm_year) ||
+		conflict (t->tm.tm_wday, u->tm.tm_yday) ||
+		conflict (t->ymodulus, u->ymodulus) ||
+		conflict (t->yweek, u->yweek) ||
+		(
+			t->zone != u->zone &&
+			t->zone != TM_UNDEFINED_ZONE &&
+			u->zone != TM_UNDEFINED_ZONE
+		)
+	)
+		return -1;
+#	undef conflict
+#	define merge_(a,b) if (TM_DEFINED (b)) (a) = (b);
+	merge_ (t->tm.tm_sec, u->tm.tm_sec)
+	merge_ (t->tm.tm_min, u->tm.tm_min)
+	merge_ (t->tm.tm_hour, u->tm.tm_hour)
+	merge_ (t->tm.tm_mday, u->tm.tm_mday)
+	merge_ (t->tm.tm_mon, u->tm.tm_mon)
+	merge_ (t->tm.tm_year, u->tm.tm_year)
+	merge_ (t->tm.tm_wday, u->tm.tm_yday)
+	merge_ (t->ymodulus, u->ymodulus)
+	merge_ (t->yweek, u->yweek)
+#	undef merge_
+	if (u->zone != TM_UNDEFINED_ZONE) t->zone = u->zone;
+	return 0;
+}
+
+	char *
+partime (s, t) char const *s; struct partime *t;
+/*
+* Parse a date/time prefix of S, putting the parsed result into *T.
+* Return the first character after the prefix.
+* The prefix may contain no useful information;
+* in that case, *T will contain only undefined values.
+*/
+{
+	struct partime p;
+
+	undefine (t);
+	while (*s) {
+		int i = 0;
+		char const *s1;
+		do {
+			if (!(s1 = parse_prefix (s, &p, &i)))
+				return (char *) s;
+		} while (merge_partime (t, &p) != 0);
+		s = s1;
+	}
+	return (char *) s;
+}
diff --git a/gnu/usr.bin/rcs/lib/partime.h b/gnu/usr.bin/rcs/lib/partime.h
new file mode 100644
index 0000000000000..5d3983fbb0482
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/partime.h
@@ -0,0 +1,71 @@
+/* Parse a string, yielding a struct partime that describes it.  */
+
+/* Copyright 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#define TM_UNDEFINED (-1)
+#define TM_DEFINED(x) (0 <= (x))
+
+#define TM_UNDEFINED_ZONE ((long) -24 * 60 * 60)
+#define TM_LOCAL_ZONE (TM_UNDEFINED_ZONE - 1)
+
+struct partime {
+	/*
+	* This structure describes the parsed time.
+	* Only the following tm_* values in it are used:
+	*	sec, min, hour, mday, mon, year, wday, yday.
+	* If TM_UNDEFINED(value), the parser never found the value.
+	* The tm_year field is the actual year, not the year - 1900;
+	* but see ymodulus below.
+	*/
+	struct tm tm;
+
+	/*
+	* If !TM_UNDEFINED(ymodulus),
+	* then tm.tm_year is actually modulo ymodulus.
+	*/
+	int ymodulus;
+
+	/*
+	* Week of year, ISO 8601 style.
+	* If TM_UNDEFINED(yweek), the parser never found yweek.
+	* Weeks start on Mondays.
+	* Week 1 includes Jan 4.
+	*/
+	int yweek;
+
+	/* Seconds east of UTC; or TM_LOCAL_ZONE or TM_UNDEFINED_ZONE.  */
+	long zone;
+};
+
+#if defined(__STDC__) || has_prototypes
+#	define __PARTIME_P(x) x
+#else
+#	define __PARTIME_P(x) ()
+#endif
+
+char *partime __PARTIME_P((char const *, struct partime *));
+char *parzone __PARTIME_P((char const *, long *));
diff --git a/gnu/usr.bin/rcs/lib/rcsbase.h b/gnu/usr.bin/rcs/lib/rcsbase.h
new file mode 100644
index 0000000000000..9f2f68cc8b6bb
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsbase.h
@@ -0,0 +1,762 @@
+/* RCS common definitions and data structures */
+
+#define RCSBASE "$FreeBSD$"
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.20  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.19  1995/06/01 16:23:43  eggert
+ * (SIZEABLE_PATH): Don't depend on PATH_MAX: it's not worth configuring.
+ * (Ioffset_type,BINARY_EXPAND,MIN_UNEXPAND,MIN_UNCHANGED_EXPAND): New macros.
+ * (maps_memory): New macro; replaces many instances of `has_mmap'.
+ * (cacheptr): Renamed from cachetell.
+ * (struct RILE): New alternate name for RILE; the type is now recursive.
+ * (deallocate): New member for RILE, used for generic buffer deallocation.
+ * (cacheunget_): No longer take a failure arg; just call Ierror on failure.
+ * (struct rcslock): Renamed from struct lock, to avoid collisions with
+ * system headers on some hosts.  All users changed.
+ * (basefilename): Renamed from basename, likewise.
+ * (dirtpname): Remove; no longer external.
+ * (dirlen, dateform): Remove; no longer used.
+ * (cmpdate, fopenSafer, fdSafer, readAccessFilenameBuffer): New functions.
+ * (zonelenmax): Increase to 9 for full ISO 8601 format.
+ * (catchmmapints): Depend on has_NFS.
+ *
+ * Revision 5.18  1994/03/17 14:05:48  eggert
+ * Add primitives for reading backwards from a RILE;
+ * this is needed to go back and find the $Log prefix.
+ * Specify subprocess input via file descriptor, not file name.  Remove lint.
+ *
+ * Revision 5.17  1993/11/09 17:40:15  eggert
+ * Move RCS-specific time handling into rcstime.c.
+ * printf_string now takes two arguments, alas.
+ *
+ * Revision 5.16  1993/11/03 17:42:27  eggert
+ * Don't arbitrarily limit the number of joins.  Remove `nil'.
+ * Add Name keyword.  Don't discard ignored phrases.
+ * Add support for merge -A vs -E, and allow up to three labels.
+ * Improve quality of diagnostics and prototypes.
+ *
+ * Revision 5.15  1992/07/28  16:12:44  eggert
+ * Statement macro names now end in _.
+ *
+ * Revision 5.14  1992/02/17  23:02:22  eggert
+ * Add -T support.  Work around NFS mmap SIGBUS problem.
+ *
+ * Revision 5.13  1992/01/24  18:44:19  eggert
+ * Add support for bad_creat0.  lint -> RCS_lint
+ *
+ * Revision 5.12  1992/01/06  02:42:34  eggert
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.11  1991/10/07  17:32:46  eggert
+ * Support piece tables even if !has_mmap.
+ *
+ * Revision 5.10  1991/09/24  00:28:39  eggert
+ * Remove unexported functions.
+ *
+ * Revision 5.9  1991/08/19  03:13:55  eggert
+ * Add piece tables and other tuneups, and NFS workarounds.
+ *
+ * Revision 5.8  1991/04/21  11:58:20  eggert
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.7  1991/02/28  19:18:50  eggert
+ * Try setuid() if seteuid() doesn't work.
+ *
+ * Revision 5.6  1991/02/26  17:48:37  eggert
+ * Support new link behavior.  Move ANSI C / Posix declarations into conf.sh.
+ *
+ * Revision 5.5  1990/12/04  05:18:43  eggert
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.4  1990/11/01  05:03:35  eggert
+ * Don't assume that builtins are functions; they may be macros.
+ * Permit arbitrary data in logs.
+ *
+ * Revision 5.3  1990/09/26  23:36:58  eggert
+ * Port wait() to non-Posix ANSI C hosts.
+ *
+ * Revision 5.2  1990/09/04  08:02:20  eggert
+ * Don't redefine NAME_MAX, PATH_MAX.
+ * Improve incomplete line handling.  Standardize yes-or-no procedure.
+ *
+ * Revision 5.1  1990/08/29  07:13:53  eggert
+ * Add -kkvl.  Fix type typos exposed by porting.  Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:12:44  eggert
+ * Adjust ANSI C / Posix support.  Add -k, -V, setuid.  Don't call access().
+ * Remove compile-time limits; use malloc instead.
+ * Ansify and Posixate.  Add support for ISO 8859.
+ * Remove snoop and v2 support.
+ *
+ * Revision 4.9  89/05/01  15:17:14  narten
+ * botched previous USG fix
+ *
+ * Revision 4.8  89/05/01  14:53:05  narten
+ * changed #include <strings.h> -> string.h for USG systems.
+ *
+ * Revision 4.7  88/11/08  15:58:45  narten
+ * removed defs for functions loaded from libraries
+ *
+ * Revision 4.6  88/08/09  19:12:36  eggert
+ * Shrink stdio code size; remove lint; permit -Dhshsize=nn.
+ *
+ * Revision 4.5  87/12/18  17:06:41  narten
+ * made removed BSD ifdef, now uses V4_2BSD
+ *
+ * Revision 4.4  87/10/18  10:29:49  narten
+ * Updating version numbers
+ * Changes relative to 1.1 are actually relative to 4.2
+ *
+ * Revision 1.3  87/09/24  14:02:25  narten
+ * changes for lint
+ *
+ * Revision 1.2  87/03/27  14:22:02  jenkins
+ * Port to suns
+ *
+ * Revision 4.2  83/12/20  16:04:20  wft
+ * merged 3.6.1.1 and 4.1 (SMALLOG, logsize).
+ * moved setting of STRICT_LOCKING to Makefile.
+ * changed DOLLAR to UNKN (conflict with KDELIM).
+ *
+ * Revision 4.1  83/05/04  09:12:41  wft
+ * Added markers Id and RCSfile.
+ * Added Dbranch for default branches.
+ *
+ * Revision 3.6.1.1  83/12/02  21:56:22  wft
+ * Increased logsize, added macro SMALLOG.
+ *
+ * Revision 3.6  83/01/15  16:43:28  wft
+ * 4.2 prerelease
+ *
+ * Revision 3.6  83/01/15  16:43:28  wft
+ * Replaced dbm.h with BYTESIZ, fixed definition of rindex().
+ * Added variants of NCPFN and NCPPN for bsd 4.2, selected by defining V4_2BSD.
+ * Added macro DELNUMFORM to have uniform format for printing delta text nodes.
+ * Added macro DELETE to mark deleted deltas.
+ *
+ * Revision 3.5  82/12/10  12:16:56  wft
+ * Added two forms of DATEFORM, one using %02d, the other %.2d.
+ *
+ * Revision 3.4  82/12/04  20:01:25  wft
+ * added LOCKER, Locker, and USG (redefinition of rindex).
+ *
+ * Revision 3.3  82/12/03  12:22:04  wft
+ * Added dbm.h, stdio.h, RCSBASE, RCSSEP, RCSSUF, WORKMODE, TMPFILE3,
+ * PRINTDATE, PRINTTIME, map, and ctab; removed Suffix. Redefined keyvallength
+ * using NCPPN. Changed putc() to abort on write error.
+ *
+ * Revision 3.2  82/10/18  15:03:52  wft
+ * added macro STRICT_LOCKING, removed RCSUMASK.
+ * renamed JOINFILE[1,2] to JOINFIL[1,2].
+ *
+ * Revision 3.1  82/10/11  19:41:17  wft
+ * removed NBPW, NBPC, NCPW.
+ * added typdef int void to aid compiling
+ */
+
+
+#include "conf.h"
+
+
+#define EXIT_TROUBLE DIFF_TROUBLE
+
+#ifdef _POSIX_PATH_MAX
+#	define SIZEABLE_PATH _POSIX_PATH_MAX
+#else
+#	define SIZEABLE_PATH 255 /* size of a large path; not a hard limit */
+#endif
+
+/* for traditional C hosts with unusual size arguments */
+#define Fread(p,s,n,f)  fread(p, (freadarg_type)(s), (freadarg_type)(n), f)
+#define Fwrite(p,s,n,f)  fwrite(p, (freadarg_type)(s), (freadarg_type)(n), f)
+
+
+/*
+ * Parameters
+ */
+
+/* backwards compatibility with old versions of RCS */
+#define VERSION_min 3		/* old output RCS format supported */
+#define VERSION_max 5		/* newest output RCS format supported */
+#ifndef VERSION_DEFAULT		/* default RCS output format */
+#	define VERSION_DEFAULT VERSION_max
+#endif
+#define VERSION(n) ((n) - VERSION_DEFAULT) /* internally, 0 is the default */
+
+#ifndef STRICT_LOCKING
+#define STRICT_LOCKING 1
+#endif
+			      /* 0 sets the default locking to non-strict;  */
+                              /* used in experimental environments.         */
+                              /* 1 sets the default locking to strict;      */
+                              /* used in production environments.           */
+
+#define yearlength	   16 /* (good through AD 9,999,999,999,999,999)    */
+#define datesize (yearlength+16)	/* size of output of time2date */
+#define RCSTMPPREFIX '_' /* prefix for temp files in working dir  */
+#define KDELIM            '$' /* delimiter for keywords                     */
+#define VDELIM            ':' /* separates keywords from values             */
+#define DEFAULTSTATE    "Exp" /* default state of revisions                 */
+
+
+
+#define true     1
+#define false    0
+
+
+/*
+ * RILE - readonly file
+ * declarecache; - declares local cache for RILE variable(s)
+ * setupcache - sets up the local RILE cache, but does not initialize it
+ * cache, uncache - caches and uncaches the local RILE;
+ *	(uncache,cache) is needed around functions that advance the RILE pointer
+ * Igeteof_(f,c,s) - get a char c from f, executing statement s at EOF
+ * cachegeteof_(c,s) - Igeteof_ applied to the local RILE
+ * Iget_(f,c) - like Igeteof_, except EOF is an error
+ * cacheget_(c) - Iget_ applied to the local RILE
+ * cacheunget_(f,c,s) - read c backwards from cached f, executing s at BOF
+ * Ifileno, Ioffset_type, Irewind, Itell - analogs to stdio routines
+ *
+ * By conventions, macros whose names end in _ are statements, not expressions.
+ * Following such macros with `; else' results in a syntax error.
+ */
+
+#define maps_memory (has_map_fd || has_mmap)
+
+#if large_memory
+	typedef unsigned char const *Iptr_type;
+	typedef struct RILE {
+		Iptr_type ptr, lim;
+		unsigned char *base; /* not Iptr_type for lint's sake */
+		unsigned char *readlim;
+		int fd;
+#		if maps_memory
+			void (*deallocate) P((struct RILE *));
+#		else
+			FILE *stream;
+#		endif
+	} RILE;
+#	if maps_memory
+#		define declarecache register Iptr_type ptr, lim
+#		define setupcache(f) (lim = (f)->lim)
+#		define Igeteof_(f,c,s) if ((f)->ptr==(f)->lim) s else (c)= *(f)->ptr++;
+#		define cachegeteof_(c,s) if (ptr==lim) s else (c)= *ptr++;
+#	else
+		int Igetmore P((RILE*));
+#		define declarecache register Iptr_type ptr; register RILE *rRILE
+#		define setupcache(f) (rRILE = (f))
+#		define Igeteof_(f,c,s) if ((f)->ptr==(f)->readlim && !Igetmore(f)) s else (c)= *(f)->ptr++;
+#		define cachegeteof_(c,s) if (ptr==rRILE->readlim && !Igetmore(rRILE)) s else (c)= *ptr++;
+#	endif
+#	define uncache(f) ((f)->ptr = ptr)
+#	define cache(f) (ptr = (f)->ptr)
+#	define Iget_(f,c) Igeteof_(f,c,Ieof();)
+#	define cacheget_(c) cachegeteof_(c,Ieof();)
+#	define cacheunget_(f,c) (c)=(--ptr)[-1];
+#	define Ioffset_type size_t
+#	define Itell(f) ((f)->ptr - (f)->base)
+#	define Irewind(f) ((f)->ptr = (f)->base)
+#	define cacheptr() ptr
+#	define Ifileno(f) ((f)->fd)
+#else
+#	define RILE FILE
+#	define declarecache register FILE *ptr
+#	define setupcache(f) (ptr = (f))
+#	define uncache(f)
+#	define cache(f)
+#	define Igeteof_(f,c,s) {if(((c)=getc(f))==EOF){testIerror(f);if(feof(f))s}}
+#	define cachegeteof_(c,s) Igeteof_(ptr,c,s)
+#	define Iget_(f,c) { if (((c)=getc(f))==EOF) testIeof(f); }
+#	define cacheget_(c) Iget_(ptr,c)
+#	define cacheunget_(f,c) if(fseek(ptr,-2L,SEEK_CUR))Ierror();else cacheget_(c)
+#	define Ioffset_type long
+#	define Itell(f) ftell(f)
+#	define Ifileno(f) fileno(f)
+#endif
+
+/* Print a char, but abort on write error.  */
+#define aputc_(c,o) { if (putc(c,o)==EOF) testOerror(o); }
+
+/* Get a character from an RCS file, perhaps copying to a new RCS file.  */
+#define GETCeof_(o,c,s) { cachegeteof_(c,s) if (o) aputc_(c,o) }
+#define GETC_(o,c) { cacheget_(c) if (o) aputc_(c,o) }
+
+
+#define WORKMODE(RCSmode, writable) (((RCSmode)&(mode_t)~(S_IWUSR|S_IWGRP|S_IWOTH)) | ((writable)?S_IWUSR:0))
+/* computes mode of working file: same as RCSmode, but write permission     */
+/* determined by writable */
+
+
+/* character classes and token codes */
+enum tokens {
+/* classes */	DELIM,	DIGIT,	IDCHAR,	NEWLN,	LETTER,	Letter,
+		PERIOD,	SBEGIN,	SPACE,	UNKN,
+/* tokens */	COLON,	ID,	NUM,	SEMI,	STRING
+};
+
+#define SDELIM  '@'     /* the actual character is needed for string handling*/
+/* SDELIM must be consistent with ctab[], so that ctab[SDELIM]==SBEGIN.
+ * there should be no overlap among SDELIM, KDELIM, and VDELIM
+ */
+
+#define isdigit(c) (((unsigned)(c)-'0') <= 9) /* faster than ctab[c]==DIGIT */
+
+
+
+
+
+/***************************************
+ * Data structures for the symbol table
+ ***************************************/
+
+/* Buffer of arbitrary data */
+struct buf {
+	char *string;
+	size_t size;
+};
+struct cbuf {
+	char const *string;
+	size_t size;
+};
+
+/* Hash table entry */
+struct hshentry {
+	char const	  * num;      /* pointer to revision number (ASCIZ) */
+	char const	  * date;     /* pointer to date of checkin	    */
+	char const	  * author;   /* login of person checking in	    */
+	char const	  * lockedby; /* who locks the revision		    */
+	char const	  * state;    /* state of revision (Exp by default) */
+	char const	  * name;     /* name (if any) by which retrieved   */
+	struct cbuf	    log;      /* log message requested at checkin   */
+        struct branchhead * branches; /* list of first revisions on branches*/
+	struct cbuf	    ig;	      /* ignored phrases in admin part	    */
+	struct cbuf	    igtext;   /* ignored phrases in deltatext part  */
+        struct hshentry   * next;     /* next revision on same branch       */
+	struct hshentry   * nexthsh;  /* next revision with same hash value */
+	long		    insertlns;/* lines inserted (computed by rlog)  */
+	long		    deletelns;/* lines deleted  (computed by rlog)  */
+	char		    selector; /* true if selected, false if deleted */
+};
+
+/* list of hash entries */
+struct hshentries {
+	struct hshentries *rest;
+	struct hshentry *first;
+};
+
+/* list element for branch lists */
+struct branchhead {
+        struct hshentry   * hsh;
+        struct branchhead * nextbranch;
+};
+
+/* accesslist element */
+struct access {
+	char const	  * login;
+        struct access     * nextaccess;
+};
+
+/* list element for locks  */
+struct rcslock {
+	char const	  * login;
+        struct hshentry   * delta;
+	struct rcslock    * nextlock;
+};
+
+/* list element for symbolic names */
+struct assoc {
+	char const	  * symbol;
+	char const	  * num;
+        struct assoc      * nextassoc;
+};
+
+
+#define mainArgs (argc,argv) int argc; char **argv;
+
+#if RCS_lint
+#	define libId(name,rcsid)
+#	define mainProg(name,cmd,rcsid) int name mainArgs
+#else
+#	define libId(name,rcsid) char const name[] = rcsid;
+#	define mainProg(n,c,i) char const Copyright[] = "Copyright 1982,1988,1989 Walter F. Tichy, Purdue CS\nCopyright 1990,1991,1992,1993,1994,1995 Paul Eggert", baseid[] = RCSBASE, cmdid[] = c; libId(n,i) int main P((int,char**)); int main mainArgs
+#endif
+
+/*
+ * Markers for keyword expansion (used in co and ident)
+ *	Every byte must have class LETTER or Letter.
+ */
+#define AUTHOR          "Author"
+#define DATE            "Date"
+#define HEADER          "Header"
+#define IDH             "Id"
+#define LOCKER          "Locker"
+#define LOG             "Log"
+#define NAME		"Name"
+#define RCSFILE         "RCSfile"
+#define REVISION        "Revision"
+#define SOURCE          "Source"
+#define STATE           "State"
+#define CVSHEADER       "CVSHeader"
+#define keylength 9 /* max length of any of the above keywords */
+
+enum markers { Nomatch, Author, Date, Header, Id,
+	       Locker, Log, Name, RCSfile, Revision, Source, State, CVSHeader,
+	       LocalId };
+	/* This must be in the same order as rcskeys.c's Keyword[] array. */
+
+#define DELNUMFORM      "\n\n%s\n%s\n"
+/* used by putdtext and scanlogtext */
+
+#define EMPTYLOG "*** empty log message ***" /* used by ci and rlog */
+
+/* main program */
+extern char const cmdid[];
+void exiterr P((void)) exiting;
+
+/* merge */
+int merge P((int,char const*,char const*const[3],char const*const[3]));
+
+/* rcsedit */
+#define ciklogsize 23 /* sizeof("checked in with -k by ") */
+extern FILE *fcopy;
+extern char const *resultname;
+extern char const ciklog[ciklogsize];
+extern int locker_expansion;
+RILE *rcswriteopen P((struct buf*,struct stat*,int));
+char const *makedirtemp P((int));
+char const *getcaller P((void));
+int addlock P((struct hshentry*,int));
+int addsymbol P((char const*,char const*,int));
+int checkaccesslist P((void));
+int chnamemod P((FILE**,char const*,char const*,int,mode_t,time_t));
+int donerewrite P((int,time_t));
+int dorewrite P((int,int));
+int expandline P((RILE*,FILE*,struct hshentry const*,int,FILE*,int));
+int findlock P((int,struct hshentry**));
+int setmtime P((char const*,time_t));
+void ORCSclose P((void));
+void ORCSerror P((void));
+void copystring P((void));
+void dirtempunlink P((void));
+void enterstring P((void));
+void finishedit P((struct hshentry const*,FILE*,int));
+void keepdirtemp P((char const*));
+void openfcopy P((FILE*));
+void snapshotedit P((FILE*));
+void xpandstring P((struct hshentry const*));
+#if has_NFS || bad_unlink
+	int un_link P((char const*));
+#else
+#	define un_link(s) unlink(s)
+#endif
+#if large_memory
+	void edit_string P((void));
+#	define editstring(delta) edit_string()
+#else
+	void editstring P((struct hshentry const*));
+#endif
+
+/* rcsfcmp */
+int rcsfcmp P((RILE*,struct stat const*,char const*,struct hshentry const*));
+
+/* rcsfnms */
+#define bufautobegin(b) clear_buf(b)
+#define clear_buf(b) (VOID ((b)->string = 0, (b)->size = 0))
+extern FILE *workstdout;
+extern char *workname;
+extern char const *RCSname;
+extern char const *suffixes;
+extern int fdlock;
+extern struct stat RCSstat;
+RILE *rcsreadopen P((struct buf*,struct stat*,int));
+char *bufenlarge P((struct buf*,char const**));
+char const *basefilename P((char const*));
+char const *getfullRCSname P((void));
+char const *getfullCVSname P((void));
+char const *maketemp P((int));
+char const *rcssuffix P((char const*));
+int pairnames P((int,char**,RILE*(*)P((struct buf*,struct stat*,int)),int,int));
+struct cbuf bufremember P((struct buf*,size_t));
+void bufalloc P((struct buf*,size_t));
+void bufautoend P((struct buf*));
+void bufrealloc P((struct buf*,size_t));
+void bufscat P((struct buf*,char const*));
+void bufscpy P((struct buf*,char const*));
+void tempunlink P((void));
+
+/* rcsgen */
+extern int interactiveflag;
+extern struct buf curlogbuf;
+char const *buildrevision P((struct hshentries const*,struct hshentry*,FILE*,int));
+int getcstdin P((void));
+int putdtext P((struct hshentry const*,char const*,FILE*,int));
+int ttystdin P((void));
+int yesorno P((int,char const*,...)) printf_string(2,3);
+struct cbuf cleanlogmsg P((char*,size_t));
+struct cbuf getsstdin P((char const*,char const*,char const*,struct buf*));
+void putdesc P((int,char*));
+void putdftext P((struct hshentry const*,RILE*,FILE*,int));
+
+/* rcskeep */
+extern int prevkeys;
+extern struct buf prevauthor, prevdate, prevname, prevrev, prevstate;
+int getoldkeys P((RILE*));
+
+/* rcskeys */
+extern char const *Keyword[];
+extern enum markers LocalIdMode;
+enum markers trymatch P((char const*));
+void setRCSLocalId(char const *);
+void setIncExc(char const *);
+
+/* rcslex */
+extern FILE *foutptr;
+extern FILE *frewrite;
+extern RILE *finptr;
+extern char const *NextString;
+extern enum tokens nexttok;
+extern int hshenter;
+extern int nerror;
+extern int nextc;
+extern int quietflag;
+extern long rcsline;
+char const *getid P((void));
+void efaterror P((char const*)) exiting;
+void enfaterror P((int,char const*)) exiting;
+void fatcleanup P((int)) exiting;
+void faterror P((char const*,...)) printf_string_exiting(1,2);
+void fatserror P((char const*,...)) printf_string_exiting(1,2);
+void rcsfaterror P((char const*,...)) printf_string_exiting(1,2);
+void Ieof P((void)) exiting;
+void Ierror P((void)) exiting;
+void Oerror P((void)) exiting;
+char *checkid P((char*,int));
+char *checksym P((char*,int));
+int eoflex P((void));
+int getkeyopt P((char const*));
+int getlex P((enum tokens));
+struct cbuf getphrases P((char const*));
+struct cbuf savestring P((struct buf*));
+struct hshentry *getnum P((void));
+void Ifclose P((RILE*));
+void Izclose P((RILE**));
+void Lexinit P((void));
+void Ofclose P((FILE*));
+void Orewind P((FILE*));
+void Ozclose P((FILE**));
+void aflush P((FILE*));
+void afputc P((int,FILE*));
+void aprintf P((FILE*,char const*,...)) printf_string(2,3);
+void aputs P((char const*,FILE*));
+void checksid P((char*));
+void checkssym P((char*));
+void diagnose P((char const*,...)) printf_string(1,2);
+void eerror P((char const*));
+void eflush P((void));
+void enerror P((int,char const*));
+void error P((char const*,...)) printf_string(1,2);
+void fvfprintf P((FILE*,char const*,va_list));
+void getkey P((char const*));
+void getkeystring P((char const*));
+void nextlex P((void));
+void oflush P((void));
+void printstring P((void));
+void readstring P((void));
+void redefined P((int));
+void rcserror P((char const*,...)) printf_string(1,2);
+void rcswarn P((char const*,...)) printf_string(1,2);
+void testIerror P((FILE*));
+void testOerror P((FILE*));
+void warn P((char const*,...)) printf_string(1,2);
+void warnignore P((void));
+void workerror P((char const*,...)) printf_string(1,2);
+void workwarn P((char const*,...)) printf_string(1,2);
+#if has_madvise && has_mmap && large_memory
+	void advise_access P((RILE*,int));
+#	define if_advise_access(p,f,advice) if (p) advise_access(f,advice)
+#else
+#	define advise_access(f,advice)
+#	define if_advise_access(p,f,advice)
+#endif
+#if large_memory && maps_memory
+	RILE *I_open P((char const*,struct stat*));
+#	define Iopen(f,m,s) I_open(f,s)
+#else
+	RILE *Iopen P((char const*,char const*,struct stat*));
+#endif
+#if !large_memory
+	void testIeof P((FILE*));
+	void Irewind P((RILE*));
+#endif
+
+/* rcsmap */
+extern enum tokens const ctab[];
+
+/* rcsrev */
+char *partialno P((struct buf*,char const*,int));
+char const *namedrev P((char const*,struct hshentry*));
+char const *tiprev P((void));
+int cmpdate P((char const*,char const*));
+int cmpnum P((char const*,char const*));
+int cmpnumfld P((char const*,char const*,int));
+int compartial P((char const*,char const*,int));
+int expandsym P((char const*,struct buf*));
+int fexpandsym P((char const*,struct buf*,RILE*));
+struct hshentry *genrevs P((char const*,char const*,char const*,char const*,struct hshentries**));
+int countnumflds P((char const*));
+void getbranchno P((char const*,struct buf*));
+
+/* rcssyn */
+/* These expand modes must agree with Expand_names[] in rcssyn.c.  */
+#define KEYVAL_EXPAND 0 /* -kkv `$Keyword: value $' */
+#define KEYVALLOCK_EXPAND 1 /* -kkvl `$Keyword: value locker $' */
+#define KEY_EXPAND 2 /* -kk `$Keyword$' */
+#define VAL_EXPAND 3 /* -kv `value' */
+#define OLD_EXPAND 4 /* -ko use old string, omitting expansion */
+#define BINARY_EXPAND 5 /* -kb like -ko, but use binary mode I/O */
+#define MIN_UNEXPAND OLD_EXPAND /* min value for no logical expansion */
+#define MIN_UNCHANGED_EXPAND (OPEN_O_BINARY ? BINARY_EXPAND : OLD_EXPAND)
+			/* min value guaranteed to yield an identical file */
+struct diffcmd {
+	long
+		line1, /* number of first line */
+		nlines, /* number of lines affected */
+		adprev, /* previous 'a' line1+1 or 'd' line1 */
+		dafter; /* sum of previous 'd' line1 and previous 'd' nlines */
+};
+extern char const      * Dbranch;
+extern struct access   * AccessList;
+extern struct assoc    * Symbols;
+extern struct cbuf Comment;
+extern struct cbuf Ignored;
+extern struct rcslock *Locks;
+extern struct hshentry * Head;
+extern int		 Expand;
+extern int               StrictLocks;
+extern int               TotalDeltas;
+extern char const *const expand_names[];
+extern char const
+	Kaccess[], Kauthor[], Kbranch[], Kcomment[],
+	Kdate[], Kdesc[], Kexpand[], Khead[], Klocks[], Klog[],
+	Knext[], Kstate[], Kstrict[], Ksymbols[], Ktext[];
+void unexpected_EOF P((void)) exiting;
+int getdiffcmd P((RILE*,int,FILE*,struct diffcmd*));
+int str2expmode P((char const*));
+void getadmin P((void));
+void getdesc P((int));
+void gettree P((void));
+void ignorephrases P((char const*));
+void initdiffcmd P((struct diffcmd*));
+void putadmin P((void));
+void putstring P((FILE*,int,struct cbuf,int));
+void puttree P((struct hshentry const*,FILE*));
+
+/* rcstime */
+#define zonelenmax 9 /* maxiumum length of time zone string, e.g. "+12:34:56" */
+char const *date2str P((char const[datesize],char[datesize + zonelenmax]));
+time_t date2time P((char const[datesize]));
+void str2date P((char const*,char[datesize]));
+void time2date P((time_t,char[datesize]));
+void zone_set P((char const*));
+
+/* rcsutil */
+extern int RCSversion;
+FILE *fopenSafer P((char const*,char const*));
+char *cgetenv P((char const*));
+char *fstr_save P((char const*));
+char *str_save P((char const*));
+char const *getusername P((int));
+int fdSafer P((int));
+int getRCSINIT P((int,char**,char***));
+int run P((int,char const*,...));
+int runv P((int,char const*,char const**));
+malloc_type fremember P((malloc_type));
+malloc_type ftestalloc P((size_t));
+malloc_type testalloc P((size_t));
+malloc_type testrealloc P((malloc_type,size_t));
+#define ftalloc(T) ftnalloc(T,1)
+#define talloc(T) tnalloc(T,1)
+#if RCS_lint
+	extern malloc_type lintalloc;
+#	define ftnalloc(T,n) (lintalloc = ftestalloc(sizeof(T)*(n)), (T*)0)
+#	define tnalloc(T,n) (lintalloc = testalloc(sizeof(T)*(n)), (T*)0)
+#	define trealloc(T,p,n) (lintalloc = testrealloc((malloc_type)0, sizeof(T)*(n)), p)
+#	define tfree(p)
+#else
+#	define ftnalloc(T,n) ((T*) ftestalloc(sizeof(T)*(n)))
+#	define tnalloc(T,n) ((T*) testalloc(sizeof(T)*(n)))
+#	define trealloc(T,p,n) ((T*) testrealloc((malloc_type)(p), sizeof(T)*(n)))
+#	define tfree(p) free((malloc_type)(p))
+#endif
+time_t now P((void));
+void awrite P((char const*,size_t,FILE*));
+void fastcopy P((RILE*,FILE*));
+void ffree P((void));
+void ffree1 P((char const*));
+void setRCSversion P((char const*));
+#if has_signal
+	void catchints P((void));
+	void ignoreints P((void));
+	void restoreints P((void));
+#else
+#	define catchints()
+#	define ignoreints()
+#	define restoreints()
+#endif
+#if has_mmap && large_memory
+#   if has_NFS && mmap_signal
+	void catchmmapints P((void));
+	void readAccessFilenameBuffer P((char const*,unsigned char const*));
+#   else
+#	define catchmmapints()
+#   endif
+#endif
+#if has_getuid
+	uid_t ruid P((void));
+#	define myself(u) ((u) == ruid())
+#else
+#	define myself(u) true
+#endif
+#if has_setuid
+	uid_t euid P((void));
+	void nosetid P((void));
+	void seteid P((void));
+	void setrid P((void));
+#else
+#	define nosetid()
+#	define seteid()
+#	define setrid()
+#endif
+
+/* version */
+extern char const RCS_version_string[];
diff --git a/gnu/usr.bin/rcs/lib/rcsedit.c b/gnu/usr.bin/rcs/lib/rcsedit.c
new file mode 100644
index 0000000000000..dc9dd307de6ae
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsedit.c
@@ -0,0 +1,1958 @@
+/* RCS stream editor */
+
+/******************************************************************************
+ *                       edits the input file according to a
+ *                       script from stdin, generated by diff -n
+ *                       performs keyword expansion
+ ******************************************************************************
+ */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.19  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.18  1995/06/01 16:23:43  eggert
+ * (dirtpname): No longer external.
+ * (do_link): Simplify logic.
+ * (finisheditline, finishedit): Replace Iseek/Itell with what they stand for.
+ * (fopen_update_truncate): Replace `#if' with `if'.
+ * (keyreplace, makedirtemp): dirlen(x) -> basefilename(x)-x.
+ *
+ * (edit_string): Fix bug: if !large_memory, a bogus trailing `@' was output
+ * at the end of incomplete lines.
+ *
+ * (keyreplace): Do not assume that seeking backwards
+ * at the start of a file will fail; on some systems it succeeds.
+ * Convert C- and Pascal-style comment starts to ` *' in comment leader.
+ *
+ * (rcswriteopen): Use fdSafer to get safer file descriptor.
+ * Open RCS file with FOPEN_RB.
+ *
+ * (chnamemod): Work around bad_NFS_rename bug; don't ignore un_link result.
+ * Fall back on chmod if fchmod fails, since it might be ENOSYS.
+ *
+ * (aflush): Move to rcslex.c.
+ *
+ * Revision 5.17  1994/03/20 04:52:58  eggert
+ * Normally calculate the $Log prefix from context, not from RCS file.
+ * Move setmtime here from rcsutil.c.  Add ORCSerror.  Remove lint.
+ *
+ * Revision 5.16  1993/11/03 17:42:27  eggert
+ * Add -z.  Add Name keyword.  If bad_unlink, ignore errno when unlink fails.
+ * Escape white space, $, and \ in keyword string file names.
+ * Don't output 2 spaces between date and time after Log.
+ *
+ * Revision 5.15  1992/07/28  16:12:44  eggert
+ * Some hosts have readlink but not ELOOP.  Avoid `unsigned'.
+ * Preserve dates more systematically.  Statement macro names now end in _.
+ *
+ * Revision 5.14  1992/02/17  23:02:24  eggert
+ * Add -T support.
+ *
+ * Revision 5.13  1992/01/24  18:44:19  eggert
+ * Add support for bad_chmod_close, bad_creat0.
+ *
+ * Revision 5.12  1992/01/06  02:42:34  eggert
+ * Add setmode parameter to chnamemod.  addsymbol now reports changes.
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.11  1991/11/03  01:11:44  eggert
+ * Move the warning about link breaking to where they're actually being broken.
+ *
+ * Revision 5.10  1991/10/07  17:32:46  eggert
+ * Support piece tables even if !has_mmap.  Fix rare NFS bugs.
+ *
+ * Revision 5.9  1991/09/17  19:07:40  eggert
+ * SGI readlink() yields ENXIO, not EINVAL, for nonlinks.
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Add piece tables, NFS bug workarounds.  Catch odd filenames.  Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:21  eggert
+ * Fix errno bugs.  Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.6  1991/02/25  07:12:40  eggert
+ * Fix setuid bug.  Support new link behavior.  Work around broken "w+" fopen.
+ *
+ * Revision 5.5  1990/12/30  05:07:35  eggert
+ * Fix report of busy RCS files when !defined(O_CREAT) | !defined(O_EXCL).
+ *
+ * Revision 5.4  1990/11/01  05:03:40  eggert
+ * Permit arbitrary data in comment leaders.
+ *
+ * Revision 5.3  1990/09/11  02:41:13  eggert
+ * Tune expandline().
+ *
+ * Revision 5.2  1990/09/04  08:02:21  eggert
+ * Count RCS lines better.  Improve incomplete line handling.
+ *
+ * Revision 5.1  1990/08/29  07:13:56  eggert
+ * Add -kkvl.
+ * Fix bug when getting revisions to files ending in incomplete lines.
+ * Fix bug in comment leader expansion.
+ *
+ * Revision 5.0  1990/08/22  08:12:47  eggert
+ * Don't require final newline.
+ * Don't append "checked in with -k by " to logs,
+ * so that checking in a program with -k doesn't change it.
+ * Don't generate trailing white space for empty comment leader.
+ * Remove compile-time limits; use malloc instead.  Add -k, -V.
+ * Permit dates past 1999/12/31.  Make lock and temp files faster and safer.
+ * Ansify and Posixate.  Check diff's output.
+ *
+ * Revision 4.8  89/05/01  15:12:35  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.7  88/11/08  13:54:14  narten
+ * misplaced semicolon caused infinite loop
+ *
+ * Revision 4.6  88/08/09  19:12:45  eggert
+ * Shrink stdio code size; allow cc -R.
+ *
+ * Revision 4.5  87/12/18  11:38:46  narten
+ * Changes from the 43. version. Don't know the significance of the
+ * first change involving "rewind". Also, additional "lint" cleanup.
+ * (Guy Harris)
+ *
+ * Revision 4.4  87/10/18  10:32:21  narten
+ * Updating version numbers. Changes relative to version 1.1 actually
+ * relative to 4.1
+ *
+ * Revision 1.4  87/09/24  13:59:29  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.3  87/09/15  16:39:39  shepler
+ * added an initializatin of the variables editline and linecorr
+ * this will be done each time a file is processed.
+ * (there was an obscure bug where if co was used to retrieve multiple files
+ *  it would dump)
+ * fix attributed to  Roy Morris @FileNet Corp ...!felix!roy
+ *
+ * Revision 1.2  87/03/27  14:22:17  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/12  13:10:30  wft
+ * Added new markers Id and RCSfile; added locker to Header and Id.
+ * Overhauled expandline completely() (problem with $01234567890123456789@).
+ * Moved trymatch() and marker table to rcskeys.c.
+ *
+ * Revision 3.7  83/05/12  13:04:39  wft
+ * Added retry to expandline to resume after failed match which ended in $.
+ * Fixed truncation problem for $19chars followed by@@.
+ * Log no longer expands full path of RCS file.
+ *
+ * Revision 3.6  83/05/11  16:06:30  wft
+ * added retry to expandline to resume after failed match which ended in $.
+ * Fixed truncation problem for $19chars followed by@@.
+ *
+ * Revision 3.5  82/12/04  13:20:56  wft
+ * Added expansion of keyword Locker.
+ *
+ * Revision 3.4  82/12/03  12:26:54  wft
+ * Added line number correction in case editing does not start at the
+ * beginning of the file.
+ * Changed keyword expansion to always print a space before closing KDELIM;
+ * Expansion for Header shortened.
+ *
+ * Revision 3.3  82/11/14  14:49:30  wft
+ * removed Suffix from keyword expansion. Replaced fclose with ffclose.
+ * keyreplace() gets log message from delta, not from curlogmsg.
+ * fixed expression overflow in while(c=putc(GETC....
+ * checked nil printing.
+ *
+ * Revision 3.2  82/10/18  21:13:39  wft
+ * I added checks for write errors during the co process, and renamed
+ * expandstring() to xpandstring().
+ *
+ * Revision 3.1  82/10/13  15:52:55  wft
+ * changed type of result of getc() from char to int.
+ * made keyword expansion loop in expandline() portable to machines
+ * without sign-extension.
+ */
+
+
+#include "rcsbase.h"
+
+libId(editId, "$FreeBSD$")
+
+static void editEndsPrematurely P((void)) exiting;
+static void editLineNumberOverflow P((void)) exiting;
+static void escape_string P((FILE*,char const*));
+static void keyreplace P((enum markers,struct hshentry const*,int,RILE*,FILE*,int));
+
+FILE *fcopy;		 /* result file descriptor			    */
+char const *resultname;	 /* result pathname				    */
+int locker_expansion;	 /* should the locker name be appended to Id val?   */
+#if !large_memory
+	static RILE *fedit; /* edit file descriptor */
+	static char const *editname; /* edit pathname */
+#endif
+static long editline; /* edit line counter; #lines before cursor   */
+static long linecorr; /* #adds - #deletes in each edit run.		    */
+               /*used to correct editline in case file is not rewound after */
+               /* applying one delta                                        */
+
+/* indexes into dirtpname */
+#define lockdirtp_index 0
+#define newRCSdirtp_index bad_creat0
+#define newworkdirtp_index (newRCSdirtp_index+1)
+#define DIRTEMPNAMES (newworkdirtp_index + 1)
+
+enum maker {notmade, real, effective};
+static struct buf dirtpname[DIRTEMPNAMES];	/* unlink these when done */
+static enum maker volatile dirtpmaker[DIRTEMPNAMES];	/* if these are set */
+#define lockname (dirtpname[lockdirtp_index].string)
+#define newRCSname (dirtpname[newRCSdirtp_index].string)
+
+
+#if has_NFS || bad_unlink
+	int
+un_link(s)
+	char const *s;
+/*
+ * Remove S, even if it is unwritable.
+ * Ignore unlink() ENOENT failures; NFS generates bogus ones.
+ */
+{
+#	if bad_unlink
+		if (unlink(s) == 0)
+			return 0;
+		else {
+			int e = errno;
+			/*
+			* Forge ahead even if errno == ENOENT; some completely
+			* brain-damaged hosts (e.g. PCTCP 2.2) yield ENOENT
+			* even for existing unwritable files.
+			*/
+			if (chmod(s, S_IWUSR) != 0) {
+				errno = e;
+				return -1;
+			}
+		}
+#	endif
+#	if has_NFS
+		return unlink(s)==0 || errno==ENOENT  ?  0  :  -1;
+#	else
+		return unlink(s);
+#	endif
+}
+#endif
+
+#if !has_rename
+#  if !has_NFS
+#	define do_link(s,t) link(s,t)
+#  else
+	static int do_link P((char const*,char const*));
+	static int
+do_link(s, t)
+	char const *s, *t;
+/* Link S to T, ignoring bogus EEXIST problems due to NFS failures.  */
+{
+	int r = link(s, t);
+
+	if (r != 0  &&  errno == EEXIST) {
+		struct stat sb, tb;
+		if (
+		    stat(s, &sb) == 0  &&
+		    stat(t, &tb) == 0  &&
+		    same_file(sb, tb, 0)
+		)
+			r = 0;
+		errno = EEXIST;
+	}
+	return r;
+}
+#  endif
+#endif
+
+
+	static void
+editEndsPrematurely()
+{
+	fatserror("edit script ends prematurely");
+}
+
+	static void
+editLineNumberOverflow()
+{
+	fatserror("edit script refers to line past end of file");
+}
+
+
+#if large_memory
+
+#if has_memmove
+#	define movelines(s1, s2, n) VOID memmove(s1, s2, (n)*sizeof(Iptr_type))
+#else
+	static void movelines P((Iptr_type*,Iptr_type const*,long));
+	static void
+movelines(s1, s2, n)
+	register Iptr_type *s1;
+	register Iptr_type const *s2;
+	register long n;
+{
+	if (s1 < s2)
+		do {
+			*s1++ = *s2++;
+		} while (--n);
+	else {
+		s1 += n;
+		s2 += n;
+		do {
+			*--s1 = *--s2;
+		} while (--n);
+	}
+}
+#endif
+
+static void deletelines P((long,long));
+static void finisheditline P((RILE*,FILE*,Iptr_type,struct hshentry const*));
+static void insertline P((long,Iptr_type));
+static void snapshotline P((FILE*,Iptr_type));
+
+/*
+ * `line' contains pointers to the lines in the currently `edited' file.
+ * It is a 0-origin array that represents linelim-gapsize lines.
+ * line[0 .. gap-1] and line[gap+gapsize .. linelim-1] hold pointers to lines.
+ * line[gap .. gap+gapsize-1] contains garbage.
+ *
+ * Any @s in lines are duplicated.
+ * Lines are terminated by \n, or (for a last partial line only) by single @.
+ */
+static Iptr_type *line;
+static size_t gap, gapsize, linelim;
+
+	static void
+insertline(n, l)
+	long n;
+	Iptr_type l;
+/* Before line N, insert line L.  N is 0-origin.  */
+{
+	if (linelim-gapsize < n)
+	    editLineNumberOverflow();
+	if (!gapsize)
+	    line =
+		!linelim ?
+			tnalloc(Iptr_type, linelim = gapsize = 1024)
+		: (
+			gap = gapsize = linelim,
+			trealloc(Iptr_type, line, linelim <<= 1)
+		);
+	if (n < gap)
+	    movelines(line+n+gapsize, line+n, gap-n);
+	else if (gap < n)
+	    movelines(line+gap, line+gap+gapsize, n-gap);
+
+	line[n] = l;
+	gap = n + 1;
+	gapsize--;
+}
+
+	static void
+deletelines(n, nlines)
+	long n, nlines;
+/* Delete lines N through N+NLINES-1.  N is 0-origin.  */
+{
+	long l = n + nlines;
+	if (linelim-gapsize < l  ||  l < n)
+	    editLineNumberOverflow();
+	if (l < gap)
+	    movelines(line+l+gapsize, line+l, gap-l);
+	else if (gap < n)
+	    movelines(line+gap, line+gap+gapsize, n-gap);
+
+	gap = n;
+	gapsize += nlines;
+}
+
+	static void
+snapshotline(f, l)
+	register FILE *f;
+	register Iptr_type l;
+{
+	register int c;
+	do {
+		if ((c = *l++) == SDELIM  &&  *l++ != SDELIM)
+			return;
+		aputc_(c, f)
+	} while (c != '\n');
+}
+
+	void
+snapshotedit(f)
+	FILE *f;
+/* Copy the current state of the edits to F.  */
+{
+	register Iptr_type *p, *lim, *l=line;
+	for (p=l, lim=l+gap;  p<lim;  )
+		snapshotline(f, *p++);
+	for (p+=gapsize, lim=l+linelim;  p<lim;  )
+		snapshotline(f, *p++);
+}
+
+	static void
+finisheditline(fin, fout, l, delta)
+	RILE *fin;
+	FILE *fout;
+	Iptr_type l;
+	struct hshentry const *delta;
+{
+	fin->ptr = l;
+	if (expandline(fin, fout, delta, true, (FILE*)0, true)  <  0)
+		faterror("finisheditline internal error");
+}
+
+	void
+finishedit(delta, outfile, done)
+	struct hshentry const *delta;
+	FILE *outfile;
+	int done;
+/*
+ * Doing expansion if DELTA is set, output the state of the edits to OUTFILE.
+ * But do nothing unless DONE is set (which means we are on the last pass).
+ */
+{
+	if (done) {
+		openfcopy(outfile);
+		outfile = fcopy;
+		if (!delta)
+			snapshotedit(outfile);
+		else {
+			register Iptr_type *p, *lim, *l = line;
+			register RILE *fin = finptr;
+			Iptr_type here = fin->ptr;
+			for (p=l, lim=l+gap;  p<lim;  )
+				finisheditline(fin, outfile, *p++, delta);
+			for (p+=gapsize, lim=l+linelim;  p<lim;  )
+				finisheditline(fin, outfile, *p++, delta);
+			fin->ptr = here;
+		}
+	}
+}
+
+/* Open a temporary NAME for output, truncating any previous contents.  */
+#   define fopen_update_truncate(name) fopenSafer(name, FOPEN_W_WORK)
+#else /* !large_memory */
+    static FILE * fopen_update_truncate P((char const*));
+    static FILE *
+fopen_update_truncate(name)
+    char const *name;
+{
+	if (bad_fopen_wplus  &&  un_link(name) != 0)
+		efaterror(name);
+	return fopenSafer(name, FOPEN_WPLUS_WORK);
+}
+#endif
+
+
+	void
+openfcopy(f)
+	FILE *f;
+{
+	if (!(fcopy = f)) {
+		if (!resultname)
+			resultname = maketemp(2);
+		if (!(fcopy = fopen_update_truncate(resultname)))
+			efaterror(resultname);
+	}
+}
+
+
+#if !large_memory
+
+	static void swapeditfiles P((FILE*));
+	static void
+swapeditfiles(outfile)
+	FILE *outfile;
+/* Function: swaps resultname and editname, assigns fedit=fcopy,
+ * and rewinds fedit for reading.  Set fcopy to outfile if nonnull;
+ * otherwise, set fcopy to be resultname opened for reading and writing.
+ */
+{
+	char const *tmpptr;
+
+	editline = 0;  linecorr = 0;
+	Orewind(fcopy);
+	fedit = fcopy;
+	tmpptr=editname; editname=resultname; resultname=tmpptr;
+	openfcopy(outfile);
+}
+
+	void
+snapshotedit(f)
+	FILE *f;
+/* Copy the current state of the edits to F.  */
+{
+	finishedit((struct hshentry *)0, (FILE*)0, false);
+	fastcopy(fedit, f);
+	Irewind(fedit);
+}
+
+	void
+finishedit(delta, outfile, done)
+	struct hshentry const *delta;
+	FILE *outfile;
+	int done;
+/* copy the rest of the edit file and close it (if it exists).
+ * if delta, perform keyword substitution at the same time.
+ * If DONE is set, we are finishing the last pass.
+ */
+{
+	register RILE *fe;
+	register FILE *fc;
+
+	fe = fedit;
+	if (fe) {
+		fc = fcopy;
+		if (delta) {
+			while (1 < expandline(fe,fc,delta,false,(FILE*)0,true))
+				;
+                } else {
+			fastcopy(fe,fc);
+                }
+		Ifclose(fe);
+        }
+	if (!done)
+		swapeditfiles(outfile);
+}
+#endif
+
+
+
+#if large_memory
+#	define copylines(upto,delta) (editline = (upto))
+#else
+	static void copylines P((long,struct hshentry const*));
+	static void
+copylines(upto, delta)
+	register long upto;
+	struct hshentry const *delta;
+/*
+ * Copy input lines editline+1..upto from fedit to fcopy.
+ * If delta, keyword expansion is done simultaneously.
+ * editline is updated. Rewinds a file only if necessary.
+ */
+{
+	register int c;
+	declarecache;
+	register FILE *fc;
+	register RILE *fe;
+
+	if (upto < editline) {
+                /* swap files */
+		finishedit((struct hshentry *)0, (FILE*)0, false);
+                /* assumes edit only during last pass, from the beginning*/
+        }
+	fe = fedit;
+	fc = fcopy;
+	if (editline < upto)
+	    if (delta)
+		do {
+		    if (expandline(fe,fc,delta,false,(FILE*)0,true) <= 1)
+			editLineNumberOverflow();
+		} while (++editline < upto);
+	    else {
+		setupcache(fe); cache(fe);
+		do {
+			do {
+				cachegeteof_(c, editLineNumberOverflow();)
+				aputc_(c, fc)
+			} while (c != '\n');
+		} while (++editline < upto);
+		uncache(fe);
+	    }
+}
+#endif
+
+
+
+	void
+xpandstring(delta)
+	struct hshentry const *delta;
+/* Function: Reads a string terminated by SDELIM from finptr and writes it
+ * to fcopy. Double SDELIM is replaced with single SDELIM.
+ * Keyword expansion is performed with data from delta.
+ * If foutptr is nonnull, the string is also copied unchanged to foutptr.
+ */
+{
+	while (1 < expandline(finptr,fcopy,delta,true,foutptr,true))
+		continue;
+}
+
+
+	void
+copystring()
+/* Function: copies a string terminated with a single SDELIM from finptr to
+ * fcopy, replacing all double SDELIM with a single SDELIM.
+ * If foutptr is nonnull, the string also copied unchanged to foutptr.
+ * editline is incremented by the number of lines copied.
+ * Assumption: next character read is first string character.
+ */
+{	register c;
+	declarecache;
+	register FILE *frew, *fcop;
+	register int amidline;
+	register RILE *fin;
+
+	fin = finptr;
+	setupcache(fin); cache(fin);
+	frew = foutptr;
+	fcop = fcopy;
+	amidline = false;
+	for (;;) {
+		GETC_(frew,c)
+		switch (c) {
+		    case '\n':
+			++editline;
+			++rcsline;
+			amidline = false;
+			break;
+		    case SDELIM:
+			GETC_(frew,c)
+			if (c != SDELIM) {
+				/* end of string */
+				nextc = c;
+				editline += amidline;
+				uncache(fin);
+				return;
+			}
+			/* fall into */
+		    default:
+			amidline = true;
+			break;
+                }
+		aputc_(c,fcop)
+        }
+}
+
+
+	void
+enterstring()
+/* Like copystring, except the string is put into the edit data structure.  */
+{
+#if !large_memory
+	editname = 0;
+	fedit = 0;
+	editline = linecorr = 0;
+	resultname = maketemp(1);
+	if (!(fcopy = fopen_update_truncate(resultname)))
+		efaterror(resultname);
+	copystring();
+#else
+	register int c;
+	declarecache;
+	register FILE *frew;
+	register long e, oe;
+	register int amidline, oamidline;
+	register Iptr_type optr;
+	register RILE *fin;
+
+	e = 0;
+	gap = 0;
+	gapsize = linelim;
+	fin = finptr;
+	setupcache(fin); cache(fin);
+	advise_access(fin, MADV_NORMAL);
+	frew = foutptr;
+	amidline = false;
+	for (;;) {
+		optr = cacheptr();
+		GETC_(frew,c)
+		oamidline = amidline;
+		oe = e;
+		switch (c) {
+		    case '\n':
+			++e;
+			++rcsline;
+			amidline = false;
+			break;
+		    case SDELIM:
+			GETC_(frew,c)
+			if (c != SDELIM) {
+				/* end of string */
+				nextc = c;
+				editline = e + amidline;
+				linecorr = 0;
+				uncache(fin);
+				return;
+			}
+			/* fall into */
+		    default:
+			amidline = true;
+			break;
+		}
+		if (!oamidline)
+			insertline(oe, optr);
+	}
+#endif
+}
+
+
+
+
+	void
+#if large_memory
+edit_string()
+#else
+  editstring(delta)
+	struct hshentry const *delta;
+#endif
+/*
+ * Read an edit script from finptr and applies it to the edit file.
+#if !large_memory
+ * The result is written to fcopy.
+ * If delta, keyword expansion is performed simultaneously.
+ * If running out of lines in fedit, fedit and fcopy are swapped.
+ * editname is the name of the file that goes with fedit.
+#endif
+ * If foutptr is set, the edit script is also copied verbatim to foutptr.
+ * Assumes that all these files are open.
+ * resultname is the name of the file that goes with fcopy.
+ * Assumes the next input character from finptr is the first character of
+ * the edit script. Resets nextc on exit.
+ */
+{
+        int ed; /* editor command */
+        register int c;
+	declarecache;
+	register FILE *frew;
+#	if !large_memory
+		register FILE *f;
+		long line_lim = LONG_MAX;
+		register RILE *fe;
+#	endif
+	register long i;
+	register RILE *fin;
+#	if large_memory
+		register long j;
+#	endif
+	struct diffcmd dc;
+
+        editline += linecorr; linecorr=0; /*correct line number*/
+	frew = foutptr;
+	fin = finptr;
+	setupcache(fin);
+	initdiffcmd(&dc);
+	while (0  <=  (ed = getdiffcmd(fin,true,frew,&dc)))
+#if !large_memory
+		if (line_lim <= dc.line1)
+			editLineNumberOverflow();
+		else
+#endif
+		if (!ed) {
+			copylines(dc.line1-1, delta);
+                        /* skip over unwanted lines */
+			i = dc.nlines;
+			linecorr -= i;
+			editline += i;
+#			if large_memory
+			    deletelines(editline+linecorr, i);
+#			else
+			    fe = fedit;
+			    do {
+                                /*skip next line*/
+				do {
+				    Igeteof_(fe, c, { if (i!=1) editLineNumberOverflow(); line_lim = dc.dafter; break; } )
+				} while (c != '\n');
+			    } while (--i);
+#			endif
+		} else {
+			/* Copy lines without deleting any.  */
+			copylines(dc.line1, delta);
+			i = dc.nlines;
+#			if large_memory
+				j = editline+linecorr;
+#			endif
+			linecorr += i;
+#if !large_memory
+			f = fcopy;
+			if (delta)
+			    do {
+				switch (expandline(fin,f,delta,true,frew,true)){
+				    case 0: case 1:
+					if (i==1)
+					    return;
+					/* fall into */
+				    case -1:
+					editEndsPrematurely();
+				}
+			    } while (--i);
+			else
+#endif
+			{
+			    cache(fin);
+			    do {
+#				if large_memory
+				    insertline(j++, cacheptr());
+#				endif
+				for (;;) {
+				    GETC_(frew, c)
+				    if (c==SDELIM) {
+					GETC_(frew, c)
+					if (c!=SDELIM) {
+					    if (--i)
+						editEndsPrematurely();
+					    nextc = c;
+					    uncache(fin);
+					    return;
+					}
+				    }
+#				    if !large_memory
+					aputc_(c, f)
+#				    endif
+				    if (c == '\n')
+					break;
+				}
+				++rcsline;
+			    } while (--i);
+			    uncache(fin);
+			}
+                }
+}
+
+
+
+/* The rest is for keyword expansion */
+
+
+
+	int
+expandline(infile, outfile, delta, delimstuffed, frewfile, dolog)
+	RILE *infile;
+	FILE *outfile, *frewfile;
+	struct hshentry const *delta;
+	int delimstuffed, dolog;
+/*
+ * Read a line from INFILE and write it to OUTFILE.
+ * Do keyword expansion with data from DELTA.
+ * If DELIMSTUFFED is true, double SDELIM is replaced with single SDELIM.
+ * If FREWFILE is set, copy the line unchanged to FREWFILE.
+ * DELIMSTUFFED must be true if FREWFILE is set.
+ * Append revision history to log only if DOLOG is set.
+ * Yields -1 if no data is copied, 0 if an incomplete line is copied,
+ * 2 if a complete line is copied; adds 1 to yield if expansion occurred.
+ */
+{
+	register c;
+	declarecache;
+	register FILE *out, *frew;
+	register char * tp;
+	register int e, ds, r;
+	char const *tlim;
+	static struct buf keyval;
+        enum markers matchresult;
+
+	setupcache(infile); cache(infile);
+	out = outfile;
+	frew = frewfile;
+	ds = delimstuffed;
+	bufalloc(&keyval, keylength+3);
+	e = 0;
+	r = -1;
+
+        for (;;) {
+	    if (ds)
+		GETC_(frew, c)
+	    else
+		cachegeteof_(c, goto uncache_exit;)
+	    for (;;) {
+		switch (c) {
+		    case SDELIM:
+			if (ds) {
+			    GETC_(frew, c)
+			    if (c != SDELIM) {
+                                /* end of string */
+                                nextc=c;
+				goto uncache_exit;
+			    }
+			}
+			/* fall into */
+		    default:
+			aputc_(c,out)
+			r = 0;
+			break;
+
+		    case '\n':
+			rcsline += ds;
+			aputc_(c,out)
+			r = 2;
+			goto uncache_exit;
+
+		    case KDELIM:
+			r = 0;
+                        /* check for keyword */
+                        /* first, copy a long enough string into keystring */
+			tp = keyval.string;
+			*tp++ = KDELIM;
+			for (;;) {
+			    if (ds)
+				GETC_(frew, c)
+			    else
+				cachegeteof_(c, goto keystring_eof;)
+			    if (tp <= &keyval.string[keylength])
+				switch (ctab[c]) {
+				    case LETTER: case Letter:
+					*tp++ = c;
+					continue;
+				    default:
+					break;
+				}
+			    break;
+                        }
+			*tp++ = c; *tp = '\0';
+			matchresult = trymatch(keyval.string+1);
+			if (matchresult==Nomatch) {
+				tp[-1] = 0;
+				aputs(keyval.string, out);
+				continue;   /* last c handled properly */
+			}
+
+			/* Now we have a keyword terminated with a K/VDELIM */
+			if (c==VDELIM) {
+			      /* try to find closing KDELIM, and replace value */
+			      tlim = keyval.string + keyval.size;
+			      for (;;) {
+				      if (ds)
+					GETC_(frew, c)
+				      else
+					cachegeteof_(c, goto keystring_eof;)
+				      if (c=='\n' || c==KDELIM)
+					break;
+				      *tp++ =c;
+				      if (tlim <= tp)
+					  tp = bufenlarge(&keyval, &tlim);
+				      if (c==SDELIM && ds) { /*skip next SDELIM */
+						GETC_(frew, c)
+						if (c != SDELIM) {
+							/* end of string before closing KDELIM or newline */
+							nextc = c;
+							goto keystring_eof;
+						}
+				      }
+			      }
+			      if (c!=KDELIM) {
+				    /* couldn't find closing KDELIM -- give up */
+				    *tp = 0;
+				    aputs(keyval.string, out);
+				    continue;   /* last c handled properly */
+			      }
+			}
+			/* now put out the new keyword value */
+			uncache(infile);
+			keyreplace(matchresult, delta, ds, infile, out, dolog);
+			cache(infile);
+			e = 1;
+			break;
+                }
+		break;
+	    }
+        }
+
+    keystring_eof:
+	*tp = 0;
+	aputs(keyval.string, out);
+    uncache_exit:
+	uncache(infile);
+	return r + e;
+}
+
+
+	static void
+escape_string(out, s)
+	register FILE *out;
+	register char const *s;
+/* Output to OUT the string S, escaping chars that would break `ci -k'.  */
+{
+    register char c;
+    for (;;)
+	switch ((c = *s++)) {
+	    case 0: return;
+	    case '\t': aputs("\\t", out); break;
+	    case '\n': aputs("\\n", out); break;
+	    case ' ': aputs("\\040", out); break;
+	    case KDELIM: aputs("\\044", out); break;
+	    case '\\': if (VERSION(5)<=RCSversion) {aputs("\\\\", out); break;}
+	    /* fall into */
+	    default: aputc_(c, out) break;
+	}
+}
+
+char const ciklog[ciklogsize] = "checked in with -k by ";
+
+	static void
+keyreplace(marker, delta, delimstuffed, infile, out, dolog)
+	enum markers marker;
+	register struct hshentry const *delta;
+	int delimstuffed;
+	RILE *infile;
+	register FILE *out;
+	int dolog;
+/* function: outputs the keyword value(s) corresponding to marker.
+ * Attributes are derived from delta.
+ */
+{
+	register char const *sp, *cp, *date;
+	register int c;
+	register size_t cs, cw, ls;
+	char const *sp1;
+	char datebuf[datesize + zonelenmax];
+	int RCSv;
+	int exp;
+
+	sp = Keyword[(int)marker];
+	exp = Expand;
+	date = delta->date;
+	RCSv = RCSversion;
+
+	if (exp != VAL_EXPAND)
+	    aprintf(out, "%c%s", KDELIM, sp);
+	if (exp != KEY_EXPAND) {
+
+	    if (exp != VAL_EXPAND)
+		aprintf(out, "%c%c", VDELIM,
+			marker==Log && RCSv<VERSION(5)  ?  '\t'  :  ' '
+		);
+
+	    switch (marker) {
+	    case Author:
+		aputs(delta->author, out);
+                break;
+	    case Date:
+		aputs(date2str(date,datebuf), out);
+                break;
+	    case Id:
+	    case LocalId:
+	    case Header:
+	    case CVSHeader:
+		if (marker == Id || RCSv < VERSION(4) ||
+		    (marker == LocalId && LocalIdMode == Id))
+			escape_string(out, basefilename(RCSname));
+		else if (marker == CVSHeader ||
+		    (marker == LocalId && LocalIdMode == CVSHeader))
+			escape_string(out, getfullCVSname());
+		else
+			escape_string(out, getfullRCSname());
+		aprintf(out, " %s %s %s %s",
+			delta->num,
+			date2str(date, datebuf),
+			delta->author,
+			  RCSv==VERSION(3) && delta->lockedby ? "Locked"
+			: delta->state
+		);
+		if (delta->lockedby)
+		    if (VERSION(5) <= RCSv) {
+			if (locker_expansion || exp==KEYVALLOCK_EXPAND)
+			    aprintf(out, " %s", delta->lockedby);
+		    } else if (RCSv == VERSION(4))
+			aprintf(out, " Locker: %s", delta->lockedby);
+                break;
+	    case Locker:
+		if (delta->lockedby)
+		    if (
+				locker_expansion
+			||	exp == KEYVALLOCK_EXPAND
+			||	RCSv <= VERSION(4)
+		    )
+			aputs(delta->lockedby, out);
+                break;
+	    case Log:
+	    case RCSfile:
+		escape_string(out, basefilename(RCSname));
+                break;
+	    case Name:
+		if (delta->name)
+			aputs(delta->name, out);
+		break;
+	    case Revision:
+		aputs(delta->num, out);
+                break;
+	    case Source:
+		escape_string(out, getfullRCSname());
+                break;
+	    case State:
+		aputs(delta->state, out);
+                break;
+	    default:
+		break;
+	    }
+	    if (exp != VAL_EXPAND)
+		afputc(' ', out);
+	}
+	if (exp != VAL_EXPAND)
+	    afputc(KDELIM, out);
+
+	if (marker == Log   &&  dolog) {
+		struct buf leader;
+
+		sp = delta->log.string;
+		ls = delta->log.size;
+		if (sizeof(ciklog)-1<=ls && !memcmp(sp,ciklog,sizeof(ciklog)-1))
+			return;
+		bufautobegin(&leader);
+		if (RCSversion < VERSION(5)) {
+		    cp = Comment.string;
+		    cs = Comment.size;
+		} else {
+		    int kdelim_found = 0;
+		    Ioffset_type chars_read = Itell(infile);
+		    declarecache;
+		    setupcache(infile); cache(infile);
+
+		    c = 0; /* Pacify `gcc -Wall'.  */
+
+		    /*
+		    * Back up to the start of the current input line,
+		    * setting CS to the number of characters before `$Log'.
+		    */
+		    cs = 0;
+		    for (;;) {
+			if (!--chars_read)
+			    goto done_backing_up;
+			cacheunget_(infile, c)
+			if (c == '\n')
+			    break;
+			if (c == SDELIM  &&  delimstuffed) {
+			    if (!--chars_read)
+				break;
+			    cacheunget_(infile, c)
+			    if (c != SDELIM) {
+				cacheget_(c)
+				break;
+			    }
+			}
+			cs += kdelim_found;
+			kdelim_found |= c==KDELIM;
+		    }
+		    cacheget_(c)
+		  done_backing_up:;
+
+		    /* Copy characters before `$Log' into LEADER.  */
+		    bufalloc(&leader, cs);
+		    cp = leader.string;
+		    for (cw = 0;  cw < cs;  cw++) {
+			leader.string[cw] = c;
+			if (c == SDELIM  &&  delimstuffed)
+			    cacheget_(c)
+			cacheget_(c)
+		    }
+
+		    /* Convert traditional C or Pascal leader to ` *'.  */
+		    for (cw = 0;  cw < cs;  cw++)
+			if (ctab[(unsigned char) cp[cw]] != SPACE)
+			    break;
+		    if (
+			cw+1 < cs
+			&&  cp[cw+1] == '*'
+			&&  (cp[cw] == '/'  ||  cp[cw] == '(')
+		    ) {
+			size_t i = cw+1;
+			for (;;)
+			    if (++i == cs) {
+				warn(
+				    "`%c* $Log' is obsolescent; use ` * $Log'.",
+				    cp[cw]
+				);
+				leader.string[cw] = ' ';
+				break;
+			    } else if (ctab[(unsigned char) cp[i]] != SPACE)
+				break;
+		    }
+
+		    /* Skip `$Log ... $' string.  */
+		    do {
+			cacheget_(c)
+		    } while (c != KDELIM);
+		    uncache(infile);
+		}
+		afputc('\n', out);
+		awrite(cp, cs, out);
+		sp1 = date2str(date, datebuf);
+		if (VERSION(5) <= RCSv) {
+		    aprintf(out, "Revision %s  %s  %s",
+			delta->num, sp1, delta->author
+		    );
+		} else {
+		    /* oddity: 2 spaces between date and time, not 1 as usual */
+		    sp1 = strchr(sp1, ' ');
+		    aprintf(out, "Revision %s  %.*s %s  %s",
+			delta->num, (int)(sp1-datebuf), datebuf, sp1,
+			delta->author
+		    );
+		}
+		/* Do not include state: it may change and is not updated.  */
+		cw = cs;
+		if (VERSION(5) <= RCSv)
+		    for (;  cw && (cp[cw-1]==' ' || cp[cw-1]=='\t');  --cw)
+			continue;
+		for (;;) {
+		    afputc('\n', out);
+		    awrite(cp, cw, out);
+		    if (!ls)
+			break;
+		    --ls;
+		    c = *sp++;
+		    if (c != '\n') {
+			awrite(cp+cw, cs-cw, out);
+			do {
+			    afputc(c,out);
+			    if (!ls)
+				break;
+			    --ls;
+			    c = *sp++;
+			} while (c != '\n');
+		    }
+		}
+		bufautoend(&leader);
+	}
+}
+
+#if has_readlink
+	static int resolve_symlink P((struct buf*));
+	static int
+resolve_symlink(L)
+	struct buf *L;
+/*
+ * If L is a symbolic link, resolve it to the name that it points to.
+ * If unsuccessful, set errno and yield -1.
+ * If it points to an existing file, yield 1.
+ * Otherwise, set errno=ENOENT and yield 0.
+ */
+{
+	char *b, a[SIZEABLE_PATH];
+	int e;
+	size_t s;
+	ssize_t r;
+	struct buf bigbuf;
+	int linkcount = MAXSYMLINKS;
+
+	b = a;
+	s = sizeof(a);
+	bufautobegin(&bigbuf);
+	while ((r = readlink(L->string,b,s))  !=  -1)
+	    if (r == s) {
+		bufalloc(&bigbuf, s<<1);
+		b = bigbuf.string;
+		s = bigbuf.size;
+	    } else if (!linkcount--) {
+#		ifndef ELOOP
+		    /*
+		    * Some pedantic Posix 1003.1-1990 hosts have readlink
+		    * but not ELOOP.  Approximate ELOOP with EMLINK.
+		    */
+#		    define ELOOP EMLINK
+#		endif
+		errno = ELOOP;
+		return -1;
+	    } else {
+		/* Splice symbolic link into L.  */
+		b[r] = '\0';
+		L->string[
+		  ROOTPATH(b)  ?  0  :  basefilename(L->string) - L->string
+		] = '\0';
+		bufscat(L, b);
+	    }
+	e = errno;
+	bufautoend(&bigbuf);
+	errno = e;
+	switch (e) {
+	    case readlink_isreg_errno: return 1;
+	    case ENOENT: return 0;
+	    default: return -1;
+	}
+}
+#endif
+
+	RILE *
+rcswriteopen(RCSbuf, status, mustread)
+	struct buf *RCSbuf;
+	struct stat *status;
+	int mustread;
+/*
+ * Create the lock file corresponding to RCSBUF.
+ * Then try to open RCSBUF for reading and yield its RILE* descriptor.
+ * Put its status into *STATUS too.
+ * MUSTREAD is true if the file must already exist, too.
+ * If all goes well, discard any previously acquired locks,
+ * and set fdlock to the file descriptor of the RCS lockfile.
+ */
+{
+	register char *tp;
+	register char const *sp, *RCSpath, *x;
+	RILE *f;
+	size_t l;
+	int e, exists, fdesc, fdescSafer, r, waslocked;
+	struct buf *dirt;
+	struct stat statbuf;
+
+	waslocked  =  0 <= fdlock;
+	exists =
+#		if has_readlink
+			resolve_symlink(RCSbuf);
+#		else
+			    stat(RCSbuf->string, &statbuf) == 0  ?  1
+			:   errno==ENOENT ? 0 : -1;
+#		endif
+	if (exists < (mustread|waslocked))
+		/*
+		 * There's an unusual problem with the RCS file;
+		 * or the RCS file doesn't exist,
+		 * and we must read or we already have a lock elsewhere.
+		 */
+		return 0;
+
+	RCSpath = RCSbuf->string;
+	sp = basefilename(RCSpath);
+	l = sp - RCSpath;
+	dirt = &dirtpname[waslocked];
+	bufscpy(dirt, RCSpath);
+	tp = dirt->string + l;
+	x = rcssuffix(RCSpath);
+#	if has_readlink
+	    if (!x) {
+		error("symbolic link to non RCS file `%s'", RCSpath);
+		errno = EINVAL;
+		return 0;
+	    }
+#	endif
+	if (*sp == *x) {
+		error("RCS pathname `%s' incompatible with suffix `%s'", sp, x);
+		errno = EINVAL;
+		return 0;
+	}
+	/* Create a lock filename that is a function of the RCS filename.  */
+	if (*x) {
+		/*
+		 * The suffix is nonempty.
+		 * The lock filename is the first char of of the suffix,
+		 * followed by the RCS filename with last char removed.  E.g.:
+		 *	foo,v	RCS filename with suffix ,v
+		 *	,foo,	lock filename
+		 */
+		*tp++ = *x;
+		while (*sp)
+			*tp++ = *sp++;
+		*--tp = 0;
+	} else {
+		/*
+		 * The suffix is empty.
+		 * The lock filename is the RCS filename
+		 * with last char replaced by '_'.
+		 */
+		while ((*tp++ = *sp++))
+			continue;
+		tp -= 2;
+		if (*tp == '_') {
+			error("RCS pathname `%s' ends with `%c'", RCSpath, *tp);
+			errno = EINVAL;
+			return 0;
+		}
+		*tp = '_';
+	}
+
+	sp = dirt->string;
+
+	f = 0;
+
+	/*
+	* good news:
+	*	open(f, O_CREAT|O_EXCL|O_TRUNC|..., OPEN_CREAT_READONLY)
+	*	is atomic according to Posix 1003.1-1990.
+	* bad news:
+	*	NFS ignores O_EXCL and doesn't comply with Posix 1003.1-1990.
+	* good news:
+	*	(O_TRUNC,OPEN_CREAT_READONLY) normally guarantees atomicity
+	*	even with NFS.
+	* bad news:
+	*	If you're root, (O_TRUNC,OPEN_CREAT_READONLY) doesn't
+	*	guarantee atomicity.
+	* good news:
+	*	Root-over-the-wire NFS access is rare for security reasons.
+	*	This bug has never been reported in practice with RCS.
+	* So we don't worry about this bug.
+	*
+	* An even rarer NFS bug can occur when clients retry requests.
+	* This can happen in the usual case of NFS over UDP.
+	* Suppose client A releases a lock by renaming ",f," to "f,v" at
+	* about the same time that client B obtains a lock by creating ",f,",
+	* and suppose A's first rename request is delayed, so A reissues it.
+	* The sequence of events might be:
+	*	A sends rename(",f,", "f,v")
+	*	B sends create(",f,")
+	*	A sends retry of rename(",f,", "f,v")
+	*	server receives, does, and acknowledges A's first rename()
+	*	A receives acknowledgment, and its RCS program exits
+	*	server receives, does, and acknowledges B's create()
+	*	server receives, does, and acknowledges A's retry of rename()
+	* This not only wrongly deletes B's lock, it removes the RCS file!
+	* Most NFS implementations have idempotency caches that usually prevent
+	* this scenario, but such caches are finite and can be overrun.
+	* This problem afflicts not only RCS, which uses open() and rename()
+	* to get and release locks; it also afflicts the traditional
+	* Unix method of using link() and unlink() to get and release locks,
+	* and the less traditional method of using mkdir() and rmdir().
+	* There is no easy workaround.
+	* Any new method based on lockf() seemingly would be incompatible with
+	* the old methods; besides, lockf() is notoriously buggy under NFS.
+	* Since this problem afflicts scads of Unix programs, but is so rare
+	* that nobody seems to be worried about it, we won't worry either.
+	*/
+#	if !open_can_creat
+#		define create(f) creat(f, OPEN_CREAT_READONLY)
+#	else
+#		define create(f) open(f, OPEN_O_BINARY|OPEN_O_LOCK|OPEN_O_WRONLY|O_CREAT|O_EXCL|O_TRUNC, OPEN_CREAT_READONLY)
+#	endif
+
+	catchints();
+	ignoreints();
+
+	/*
+	 * Create a lock file for an RCS file.  This should be atomic, i.e.
+	 * if two processes try it simultaneously, at most one should succeed.
+	 */
+	seteid();
+	fdesc = create(sp);
+	fdescSafer = fdSafer(fdesc); /* Do it now; setrid might use stderr.  */
+	e = errno;
+	setrid();
+
+	if (0 <= fdesc)
+		dirtpmaker[0] = effective;
+
+	if (fdescSafer < 0) {
+		if (e == EACCES  &&  stat(sp,&statbuf) == 0)
+			/* The RCS file is busy.  */
+			e = EEXIST;
+	} else {
+		e = ENOENT;
+		if (exists) {
+		    f = Iopen(RCSpath, FOPEN_RB, status);
+		    e = errno;
+		    if (f && waslocked) {
+			/* Discard the previous lock in favor of this one.  */
+			ORCSclose();
+			seteid();
+			r = un_link(lockname);
+			e = errno;
+			setrid();
+			if (r != 0)
+			    enfaterror(e, lockname);
+			bufscpy(&dirtpname[lockdirtp_index], sp);
+		    }
+		}
+		fdlock = fdescSafer;
+	}
+
+	restoreints();
+
+	errno = e;
+	return f;
+}
+
+	void
+keepdirtemp(name)
+	char const *name;
+/* Do not unlink name, either because it's not there any more,
+ * or because it has already been unlinked.
+ */
+{
+	register int i;
+	for (i=DIRTEMPNAMES; 0<=--i; )
+		if (dirtpname[i].string == name) {
+			dirtpmaker[i] = notmade;
+			return;
+		}
+	faterror("keepdirtemp");
+}
+
+	char const *
+makedirtemp(isworkfile)
+	int isworkfile;
+/*
+ * Create a unique pathname and store it into dirtpname.
+ * Because of storage in tpnames, dirtempunlink() can unlink the file later.
+ * Return a pointer to the pathname created.
+ * If ISWORKFILE is 1, put it into the working file's directory;
+ * if 0, put the unique file in RCSfile's directory.
+ */
+{
+	register char *tp, *np;
+	register size_t dl;
+	register struct buf *bn;
+	register char const *name = isworkfile ? workname : RCSname;
+#	if has_mktemp
+	int fd;
+#	endif
+
+	dl = basefilename(name) - name;
+	bn = &dirtpname[newRCSdirtp_index + isworkfile];
+	bufalloc(bn,
+#		if has_mktemp
+			dl + 9
+#		else
+			strlen(name) + 3
+#		endif
+	);
+	bufscpy(bn, name);
+	np = tp = bn->string;
+	tp += dl;
+	*tp++ = '_';
+	*tp++ = '0'+isworkfile;
+	catchints();
+#	if has_mktemp
+		VOID strcpy(tp, "XXXXXX");
+		fd = mkstemp(np);
+		if (fd < 0 || !*np)
+		    faterror("can't make temporary pathname `%.*s_%cXXXXXX'",
+			(int)dl, name, '0'+isworkfile
+		    );
+		close(fd);
+#	else
+		/*
+		 * Posix 1003.1-1990 has no reliable way
+		 * to create a unique file in a named directory.
+		 * We fudge here.  If the filename is abcde,
+		 * the temp filename is _Ncde where N is a digit.
+		 */
+		name += dl;
+		if (*name) name++;
+		if (*name) name++;
+		VOID strcpy(tp, name);
+#	endif
+	dirtpmaker[newRCSdirtp_index + isworkfile] = real;
+	return np;
+}
+
+	void
+dirtempunlink()
+/* Clean up makedirtemp() files.  May be invoked by signal handler. */
+{
+	register int i;
+	enum maker m;
+
+	for (i = DIRTEMPNAMES;  0 <= --i;  )
+	    if ((m = dirtpmaker[i]) != notmade) {
+		if (m == effective)
+		    seteid();
+		VOID un_link(dirtpname[i].string);
+		if (m == effective)
+		    setrid();
+		dirtpmaker[i] = notmade;
+	    }
+}
+
+
+	int
+#if has_prototypes
+chnamemod(
+	FILE **fromp, char const *from, char const *to,
+	int set_mode, mode_t mode, time_t mtime
+)
+  /* The `#if has_prototypes' is needed because mode_t might promote to int.  */
+#else
+  chnamemod(fromp, from, to, set_mode, mode, mtime)
+	FILE **fromp; char const *from,*to;
+	int set_mode; mode_t mode; time_t mtime;
+#endif
+/*
+ * Rename a file (with stream pointer *FROMP) from FROM to TO.
+ * FROM already exists.
+ * If 0 < SET_MODE, change the mode to MODE, before renaming if possible.
+ * If MTIME is not -1, change its mtime to MTIME before renaming.
+ * Close and clear *FROMP before renaming it.
+ * Unlink TO if it already exists.
+ * Return -1 on error (setting errno), 0 otherwise.
+ */
+{
+	mode_t mode_while_renaming = mode;
+	int fchmod_set_mode = 0;
+
+#	if bad_a_rename || bad_NFS_rename
+	    struct stat st;
+	    if (bad_NFS_rename  ||  (bad_a_rename && set_mode <= 0)) {
+		if (fstat(fileno(*fromp), &st) != 0)
+		    return -1;
+		if (bad_a_rename && set_mode <= 0)
+		    mode = st.st_mode;
+	    }
+#	endif
+
+#	if bad_a_rename
+		/*
+		* There's a short window of inconsistency
+		* during which the lock file is writable.
+		*/
+		mode_while_renaming = mode|S_IWUSR;
+		if (mode != mode_while_renaming)
+		    set_mode = 1;
+#	endif
+
+#	if has_fchmod
+	    if (0<set_mode  &&  fchmod(fileno(*fromp),mode_while_renaming) == 0)
+		fchmod_set_mode = set_mode;
+#	endif
+	/* If bad_chmod_close, we must close before chmod.  */
+	Ozclose(fromp);
+	if (fchmod_set_mode<set_mode  &&  chmod(from, mode_while_renaming) != 0)
+	    return -1;
+
+	if (setmtime(from, mtime) != 0)
+		return -1;
+
+#	if !has_rename || bad_b_rename
+		/*
+		* There's a short window of inconsistency
+		* during which TO does not exist.
+		*/
+		if (un_link(to) != 0  &&  errno != ENOENT)
+			return -1;
+#	endif
+
+#	if has_rename
+	    if (rename(from,to) != 0  &&  !(has_NFS && errno==ENOENT))
+		return -1;
+#	else
+	    if (do_link(from,to) != 0  ||  un_link(from) != 0)
+		return -1;
+#	endif
+
+#	if bad_NFS_rename
+	{
+	    /*
+	    * Check whether the rename falsely reported success.
+	    * A race condition can occur between the rename and the stat.
+	    */
+	    struct stat tostat;
+	    if (stat(to, &tostat) != 0)
+		return -1;
+	    if (! same_file(st, tostat, 0)) {
+		errno = EIO;
+		return -1;
+	    }
+	}
+#	endif
+
+#	if bad_a_rename
+	    if (0 < set_mode  &&  chmod(to, mode) != 0)
+		return -1;
+#	endif
+
+	return 0;
+}
+
+	int
+setmtime(file, mtime)
+	char const *file;
+	time_t mtime;
+/* Set FILE's last modified time to MTIME, but do nothing if MTIME is -1.  */
+{
+	static struct utimbuf amtime; /* static so unused fields are zero */
+	if (mtime == -1)
+		return 0;
+	amtime.actime = now();
+	amtime.modtime = mtime;
+	return utime(file, &amtime);
+}
+
+
+
+	int
+findlock(delete, target)
+	int delete;
+	struct hshentry **target;
+/*
+ * Find the first lock held by caller and return a pointer
+ * to the locked delta; also removes the lock if DELETE.
+ * If one lock, put it into *TARGET.
+ * Return 0 for no locks, 1 for one, 2 for two or more.
+ */
+{
+	register struct rcslock *next, **trail, **found;
+
+	found = 0;
+	for (trail = &Locks;  (next = *trail);  trail = &next->nextlock)
+		if (strcmp(getcaller(), next->login)  ==  0) {
+			if (found) {
+				rcserror("multiple revisions locked by %s; please specify one", getcaller());
+				return 2;
+			}
+			found = trail;
+		}
+	if (!found)
+		return 0;
+	next = *found;
+	*target = next->delta;
+	if (delete) {
+		next->delta->lockedby = 0;
+		*found = next->nextlock;
+	}
+	return 1;
+}
+
+	int
+addlock(delta, verbose)
+	struct hshentry * delta;
+	int verbose;
+/*
+ * Add a lock held by caller to DELTA and yield 1 if successful.
+ * Print an error message if verbose and yield -1 if no lock is added because
+ * DELTA is locked by somebody other than caller.
+ * Return 0 if the caller already holds the lock.
+ */
+{
+	register struct rcslock *next;
+
+	for (next = Locks;  next;  next = next->nextlock)
+		if (cmpnum(delta->num, next->delta->num) == 0)
+			if (strcmp(getcaller(), next->login) == 0)
+				return 0;
+			else {
+				if (verbose)
+				  rcserror("Revision %s is already locked by %s.",
+					delta->num, next->login
+				  );
+				return -1;
+			}
+	next = ftalloc(struct rcslock);
+	delta->lockedby = next->login = getcaller();
+	next->delta = delta;
+	next->nextlock = Locks;
+	Locks = next;
+	return 1;
+}
+
+
+	int
+addsymbol(num, name, rebind)
+	char const *num, *name;
+	int rebind;
+/*
+ * Associate with revision NUM the new symbolic NAME.
+ * If NAME already exists and REBIND is set, associate NAME with NUM;
+ * otherwise, print an error message and return false;
+ * Return -1 if unsuccessful, 0 if no change, 1 if change.
+ */
+{
+	register struct assoc *next;
+
+	for (next = Symbols;  next;  next = next->nextassoc)
+		if (strcmp(name, next->symbol)  ==  0)
+			if (strcmp(next->num,num) == 0)
+				return 0;
+			else if (rebind) {
+				next->num = num;
+				return 1;
+			} else {
+				rcserror("symbolic name %s already bound to %s",
+					name, next->num
+				);
+				return -1;
+			}
+	next = ftalloc(struct assoc);
+	next->symbol = name;
+	next->num = num;
+	next->nextassoc = Symbols;
+	Symbols = next;
+	return 1;
+}
+
+
+
+	char const *
+getcaller()
+/* Get the caller's login name.  */
+{
+#	if has_setuid
+		return getusername(euid()!=ruid());
+#	else
+		return getusername(false);
+#	endif
+}
+
+
+	int
+checkaccesslist()
+/*
+ * Return true if caller is the superuser, the owner of the
+ * file, the access list is empty, or caller is on the access list.
+ * Otherwise, print an error message and return false.
+ */
+{
+	register struct access const *next;
+
+	if (!AccessList || myself(RCSstat.st_uid) || strcmp(getcaller(),"root")==0)
+		return true;
+
+	next = AccessList;
+	do {
+		if (strcmp(getcaller(), next->login)  ==  0)
+			return true;
+	} while ((next = next->nextaccess));
+
+	rcserror("user %s not on the access list", getcaller());
+	return false;
+}
+
+
+	int
+dorewrite(lockflag, changed)
+	int lockflag, changed;
+/*
+ * Do nothing if LOCKFLAG is zero.
+ * Prepare to rewrite an RCS file if CHANGED is positive.
+ * Stop rewriting if CHANGED is zero, because there won't be any changes.
+ * Fail if CHANGED is negative.
+ * Return 0 on success, -1 on failure.
+ */
+{
+	int r = 0, e;
+
+	if (lockflag)
+		if (changed) {
+			if (changed < 0)
+				return -1;
+			putadmin();
+			puttree(Head, frewrite);
+			aprintf(frewrite, "\n\n%s%c", Kdesc, nextc);
+			foutptr = frewrite;
+		} else {
+#			if bad_creat0
+				int nr = !!frewrite, ne = 0;
+#			endif
+			ORCSclose();
+			seteid();
+			ignoreints();
+#			if bad_creat0
+				if (nr) {
+					nr = un_link(newRCSname);
+					ne = errno;
+					keepdirtemp(newRCSname);
+				}
+#			endif
+			r = un_link(lockname);
+			e = errno;
+			keepdirtemp(lockname);
+			restoreints();
+			setrid();
+			if (r != 0)
+				enerror(e, lockname);
+#			if bad_creat0
+				if (nr != 0) {
+					enerror(ne, newRCSname);
+					r = -1;
+				}
+#			endif
+		}
+	return r;
+}
+
+	int
+donerewrite(changed, newRCStime)
+	int changed;
+	time_t newRCStime;
+/*
+ * Finish rewriting an RCS file if CHANGED is nonzero.
+ * Set its mode if CHANGED is positive.
+ * Set its modification time to NEWRCSTIME unless it is -1.
+ * Return 0 on success, -1 on failure.
+ */
+{
+	int r = 0, e = 0;
+#	if bad_creat0
+		int lr, le;
+#	endif
+
+	if (changed && !nerror) {
+		if (finptr) {
+			fastcopy(finptr, frewrite);
+			Izclose(&finptr);
+		}
+		if (1 < RCSstat.st_nlink)
+			rcswarn("breaking hard link");
+		aflush(frewrite);
+		seteid();
+		ignoreints();
+		r = chnamemod(
+			&frewrite, newRCSname, RCSname, changed,
+			RCSstat.st_mode & (mode_t)~(S_IWUSR|S_IWGRP|S_IWOTH),
+			newRCStime
+		);
+		e = errno;
+		keepdirtemp(newRCSname);
+#		if bad_creat0
+			lr = un_link(lockname);
+			le = errno;
+			keepdirtemp(lockname);
+#		endif
+		restoreints();
+		setrid();
+		if (r != 0) {
+			enerror(e, RCSname);
+			error("saved in %s", newRCSname);
+		}
+#		if bad_creat0
+			if (lr != 0) {
+				enerror(le, lockname);
+				r = -1;
+			}
+#		endif
+	}
+	return r;
+}
+
+	void
+ORCSclose()
+{
+	if (0 <= fdlock) {
+		if (close(fdlock) != 0)
+			efaterror(lockname);
+		fdlock = -1;
+	}
+	Ozclose(&frewrite);
+}
+
+	void
+ORCSerror()
+/*
+* Like ORCSclose, except we are cleaning up after an interrupt or fatal error.
+* Do not report errors, since this may loop.  This is needed only because
+* some brain-damaged hosts (e.g. OS/2) cannot unlink files that are open, and
+* some nearly-Posix hosts (e.g. NFS) work better if the files are closed first.
+* This isn't a completely reliable away to work around brain-damaged hosts,
+* because of the gap between actual file opening and setting frewrite etc.,
+* but it's better than nothing.
+*/
+{
+	if (0 <= fdlock)
+		VOID close(fdlock);
+	if (frewrite)
+		/* Avoid fclose, since stdio may not be reentrant.  */
+		VOID close(fileno(frewrite));
+}
diff --git a/gnu/usr.bin/rcs/lib/rcsfcmp.c b/gnu/usr.bin/rcs/lib/rcsfcmp.c
new file mode 100644
index 0000000000000..ef0529001b872
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsfcmp.c
@@ -0,0 +1,354 @@
+/* Compare working files, ignoring RCS keyword strings.  */
+
+/*****************************************************************************
+ *                       rcsfcmp()
+ *                       Testprogram: define FCMPTEST
+ *****************************************************************************
+ */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+
+
+
+
+/*
+ * Revision 5.14  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.13  1995/06/01 16:23:43  eggert
+ * (rcsfcmp): Add -kb support.
+ *
+ * Revision 5.12  1994/03/17 14:05:48  eggert
+ * Normally calculate the $Log prefix from context, not from RCS file.
+ * Calculate line numbers correctly even if the $Log prefix contains newlines.
+ * Remove lint.
+ *
+ * Revision 5.11  1993/11/03 17:42:27  eggert
+ * Fix yet another off-by-one error when comparing Log string expansions.
+ *
+ * Revision 5.10  1992/07/28 16:12:44  eggert
+ * Statement macro names now end in _.
+ *
+ * Revision 5.9  1991/10/07  17:32:46  eggert
+ * Count log lines correctly.
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:22  eggert
+ * Fix errno bug.  Add MS-DOS support.
+ *
+ * Revision 5.6  1991/02/28  19:18:47  eggert
+ * Open work file at most once.
+ *
+ * Revision 5.5  1990/11/27  09:26:05  eggert
+ * Fix comment leader bug.
+ *
+ * Revision 5.4  1990/11/01  05:03:42  eggert
+ * Permit arbitrary data in logs and comment leaders.
+ *
+ * Revision 5.3  1990/09/11  02:41:15  eggert
+ * Don't ignore differences inside keyword strings if -ko is set.
+ *
+ * Revision 5.1  1990/08/29  07:13:58  eggert
+ * Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:12:49  eggert
+ * Don't append "checked in with -k by " log to logs,
+ * so that checking in a program with -k doesn't change it.
+ * Ansify and Posixate.  Remove lint.
+ *
+ * Revision 4.5  89/05/01  15:12:42  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.4  88/08/09  19:12:50  eggert
+ * Shrink stdio code size.
+ *
+ * Revision 4.3  87/12/18  11:40:02  narten
+ * lint cleanups (Guy Harris)
+ *
+ * Revision 4.2  87/10/18  10:33:06  narten
+ * updting version number. Changes relative to 1.1 actually relative to
+ * 4.1
+ *
+ * Revision 1.2  87/03/27  14:22:19  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/10  16:24:04  wft
+ * Marker matching now uses trymatch(). Marker pattern is now
+ * checked precisely.
+ *
+ * Revision 3.1  82/12/04  13:21:40  wft
+ * Initial revision.
+ *
+ */
+
+/*
+#define FCMPTEST
+*/
+/* Testprogram; prints out whether two files are identical,
+ * except for keywords
+ */
+
+#include  "rcsbase.h"
+
+libId(fcmpId, "$FreeBSD$")
+
+	static int discardkeyval P((int,RILE*));
+	static int
+discardkeyval(c, f)
+	register int c;
+	register RILE *f;
+{
+	for (;;)
+		switch (c) {
+			case KDELIM:
+			case '\n':
+				return c;
+			default:
+				Igeteof_(f, c, return EOF;)
+				break;
+		}
+}
+
+	int
+rcsfcmp(xfp, xstatp, uname, delta)
+	register RILE *xfp;
+	struct stat const *xstatp;
+	char const *uname;
+	struct hshentry const *delta;
+/* Compare the files xfp and uname.  Return zero
+ * if xfp has the same contents as uname and neither has keywords,
+ * otherwise -1 if they are the same ignoring keyword values,
+ * and 1 if they differ even ignoring
+ * keyword values. For the LOG-keyword, rcsfcmp skips the log message
+ * given by the parameter delta in xfp.  Thus, rcsfcmp returns nonpositive
+ * if xfp contains the same as uname, with the keywords expanded.
+ * Implementation: character-by-character comparison until $ is found.
+ * If a $ is found, read in the marker keywords; if they are real keywords
+ * and identical, read in keyword value. If value is terminated properly,
+ * disregard it and optionally skip log message; otherwise, compare value.
+ */
+{
+    register int xc, uc;
+    char xkeyword[keylength+2];
+    int eqkeyvals;
+    register RILE *ufp;
+    register int xeof, ueof;
+    register char * tp;
+    register char const *sp;
+    register size_t leaderlen;
+    int result;
+    enum markers match1;
+    struct stat ustat;
+
+    if (!(ufp = Iopen(uname, FOPEN_R_WORK, &ustat))) {
+       efaterror(uname);
+    }
+    xeof = ueof = false;
+    if (MIN_UNEXPAND <= Expand) {
+	if (!(result = xstatp->st_size!=ustat.st_size)) {
+#	    if large_memory && maps_memory
+		result = !!memcmp(xfp->base,ufp->base,(size_t)xstatp->st_size);
+#	    else
+		for (;;) {
+		    /* get the next characters */
+		    Igeteof_(xfp, xc, xeof=true;)
+		    Igeteof_(ufp, uc, ueof=true;)
+		    if (xeof | ueof)
+			goto eof;
+		    if (xc != uc)
+			goto return1;
+		}
+#	    endif
+	}
+    } else {
+	xc = 0;
+	uc = 0; /* Keep lint happy.  */
+	leaderlen = 0;
+	result = 0;
+
+	for (;;) {
+	  if (xc != KDELIM) {
+	    /* get the next characters */
+	    Igeteof_(xfp, xc, xeof=true;)
+	    Igeteof_(ufp, uc, ueof=true;)
+	    if (xeof | ueof)
+		goto eof;
+	  } else {
+	    /* try to get both keywords */
+	    tp = xkeyword;
+	    for (;;) {
+		Igeteof_(xfp, xc, xeof=true;)
+		Igeteof_(ufp, uc, ueof=true;)
+		if (xeof | ueof)
+		    goto eof;
+		if (xc != uc)
+		    break;
+		switch (xc) {
+		    default:
+			if (xkeyword+keylength <= tp)
+			    break;
+			*tp++ = xc;
+			continue;
+		    case '\n': case KDELIM: case VDELIM:
+			break;
+		}
+		break;
+	    }
+	    if (
+		(xc==KDELIM || xc==VDELIM)  &&  (uc==KDELIM || uc==VDELIM)  &&
+		(*tp = xc,  (match1 = trymatch(xkeyword)) != Nomatch)
+	    ) {
+#ifdef FCMPTEST
+	      VOID printf("found common keyword %s\n",xkeyword);
+#endif
+	      result = -1;
+	      for (;;) {
+		  if (xc != uc) {
+		      xc = discardkeyval(xc, xfp);
+		      uc = discardkeyval(uc, ufp);
+		      if ((xeof = xc==EOF)  |  (ueof = uc==EOF))
+			  goto eof;
+		      eqkeyvals = false;
+		      break;
+		  }
+		  switch (xc) {
+		      default:
+			  Igeteof_(xfp, xc, xeof=true;)
+			  Igeteof_(ufp, uc, ueof=true;)
+			  if (xeof | ueof)
+			      goto eof;
+			  continue;
+
+		      case '\n': case KDELIM:
+			  eqkeyvals = true;
+			  break;
+		  }
+		  break;
+	      }
+	      if (xc != uc)
+		  goto return1;
+	      if (xc==KDELIM) {
+		  /* Skip closing KDELIM.  */
+		  Igeteof_(xfp, xc, xeof=true;)
+		  Igeteof_(ufp, uc, ueof=true;)
+		  if (xeof | ueof)
+		      goto eof;
+		  /* if the keyword is LOG, also skip the log message in xfp*/
+		  if (match1==Log) {
+		      /* first, compute the number of line feeds in log msg */
+		      int lncnt;
+		      size_t ls, ccnt;
+		      sp = delta->log.string;
+		      ls = delta->log.size;
+		      if (ls<sizeof(ciklog)-1 || memcmp(sp,ciklog,sizeof(ciklog)-1)) {
+			/*
+			* This log message was inserted.  Skip its header.
+			* The number of newlines to skip is
+			* 1 + (C+1)*(1+L+1), where C is the number of newlines
+			* in the comment leader, and L is the number of
+			* newlines in the log string.
+			*/
+			int c1 = 1;
+			for (ccnt=Comment.size; ccnt--; )
+			    c1 += Comment.string[ccnt] == '\n';
+			lncnt = 2*c1 + 1;
+			while (ls--) if (*sp++=='\n') lncnt += c1;
+			for (;;) {
+			    if (xc=='\n')
+				if(--lncnt==0) break;
+			    Igeteof_(xfp, xc, goto returnresult;)
+			}
+			/* skip last comment leader */
+			/* Can't just skip another line here, because there may be */
+			/* additional characters on the line (after the Log....$)  */
+			ccnt = RCSversion<VERSION(5) ? Comment.size : leaderlen;
+			do {
+			    Igeteof_(xfp, xc, goto returnresult;)
+			    /*
+			     * Read to the end of the comment leader or '\n',
+			     * whatever comes first, because the leader's
+			     * trailing white space was probably stripped.
+			     */
+			} while (ccnt-- && (xc!='\n' || --c1));
+		      }
+		  }
+	      } else {
+		  /* both end in the same character, but not a KDELIM */
+		  /* must compare string values.*/
+#ifdef FCMPTEST
+		  VOID printf("non-terminated keywords %s, potentially different values\n",xkeyword);
+#endif
+		  if (!eqkeyvals)
+		      goto return1;
+	      }
+	    }
+	  }
+	  if (xc != uc)
+	      goto return1;
+	  if (xc == '\n')
+	      leaderlen = 0;
+	  else
+	      leaderlen++;
+	}
+    }
+
+  eof:
+    if (xeof==ueof)
+	goto returnresult;
+  return1:
+    result = 1;
+  returnresult:
+    Ifclose(ufp);
+    return result;
+}
+
+
+
+#ifdef FCMPTEST
+
+char const cmdid[] = "rcsfcmp";
+
+main(argc, argv)
+int  argc; char  *argv[];
+/* first argument: comment leader; 2nd: log message, 3rd: expanded file,
+ * 4th: unexpanded file
+ */
+{       struct hshentry delta;
+
+	Comment.string = argv[1];
+	Comment.size = strlen(argv[1]);
+	delta.log.string = argv[2];
+	delta.log.size = strlen(argv[2]);
+	if (rcsfcmp(Iopen(argv[3], FOPEN_R_WORK, (struct stat*)0), argv[4], &delta))
+                VOID printf("files are the same\n");
+        else    VOID printf("files are different\n");
+}
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcsfnms.c b/gnu/usr.bin/rcs/lib/rcsfnms.c
new file mode 100644
index 0000000000000..00caec5adf6f4
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsfnms.c
@@ -0,0 +1,1132 @@
+/* RCS filename and pathname handling */
+
+/****************************************************************************
+ *                     creation and deletion of /tmp temporaries
+ *		       pairing of RCS pathnames and working pathnames.
+ *                     Testprogram: define PAIRTEST
+ ****************************************************************************
+ */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+
+
+
+/*
+ * Revision 5.16  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.15  1995/06/01 16:23:43  eggert
+ * (basefilename): Renamed from basename to avoid collisions.
+ * (dirlen): Remove (for similar reasons).
+ * (rcsreadopen): Open with FOPEN_RB.
+ * (SLASHSLASH_is_SLASH): Default is 0.
+ * (getcwd): Work around bad_wait_if_SIGCHLD_ignored bug.
+ *
+ * Revision 5.14  1994/03/17 14:05:48  eggert
+ * Strip trailing SLASHes from TMPDIR; some systems need this.  Remove lint.
+ *
+ * Revision 5.13  1993/11/03 17:42:27  eggert
+ * Determine whether a file name is too long indirectly,
+ * by examining inode numbers, instead of trying to use operating system
+ * primitives like pathconf, which are not trustworthy in general.
+ * File names may now hold white space or $.
+ * Do not flatten ../X in pathnames; that may yield wrong answer for symlinks.
+ * Add getabsname hook.  Improve quality of diagnostics.
+ *
+ * Revision 5.12  1992/07/28  16:12:44  eggert
+ * Add .sty.  .pl now implies Perl, not Prolog.  Fix fdlock initialization bug.
+ * Check that $PWD is really ".".  Be consistent about pathnames vs filenames.
+ *
+ * Revision 5.11  1992/02/17  23:02:25  eggert
+ * `a/RCS/b/c' is now an RCS file with an empty extension, not just `a/b/RCS/c'.
+ *
+ * Revision 5.10  1992/01/24  18:44:19  eggert
+ * Fix bug: Expand and Ignored weren't reinitialized.
+ * Avoid `char const c=ch;' compiler bug.
+ * Add support for bad_creat0.
+ *
+ * Revision 5.9  1992/01/06  02:42:34  eggert
+ * Shorten long (>31 chars) name.
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.8  1991/09/24  00:28:40  eggert
+ * Don't export bindex().
+ *
+ * Revision 5.7  1991/08/19  03:13:55  eggert
+ * Fix messages when rcswriteopen fails.
+ * Look in $TMP and $TEMP if $TMPDIR isn't set.  Tune.
+ *
+ * Revision 5.6  1991/04/21  11:58:23  eggert
+ * Fix errno bugs.  Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.5  1991/02/26  17:48:38  eggert
+ * Fix setuid bug.  Support new link behavior.
+ * Define more portable getcwd().
+ *
+ * Revision 5.4  1990/11/01  05:03:43  eggert
+ * Permit arbitrary data in comment leaders.
+ *
+ * Revision 5.3  1990/09/14  22:56:16  hammer
+ * added more filename extensions and their comment leaders
+ *
+ * Revision 5.2  1990/09/04  08:02:23  eggert
+ * Fix typo when !RCSSEP.
+ *
+ * Revision 5.1  1990/08/29  07:13:59  eggert
+ * Work around buggy compilers with defective argument promotion.
+ *
+ * Revision 5.0  1990/08/22  08:12:50  eggert
+ * Ignore signals when manipulating the semaphore file.
+ * Modernize list of filename extensions.
+ * Permit paths of arbitrary length.  Beware filenames beginning with "-".
+ * Remove compile-time limits; use malloc instead.
+ * Permit dates past 1999/12/31.  Make lock and temp files faster and safer.
+ * Ansify and Posixate.
+ * Don't use access().  Fix test for non-regular files.  Tune.
+ *
+ * Revision 4.8  89/05/01  15:09:41  narten
+ * changed getwd to not stat empty directories.
+ *
+ * Revision 4.7  88/08/09  19:12:53  eggert
+ * Fix troff macro comment leader bug; add Prolog; allow cc -R; remove lint.
+ *
+ * Revision 4.6  87/12/18  11:40:23  narten
+ * additional file types added from 4.3 BSD version, and SPARC assembler
+ * comment character added. Also, more lint cleanups. (Guy Harris)
+ *
+ * Revision 4.5  87/10/18  10:34:16  narten
+ * Updating version numbers. Changes relative to 1.1 actually relative
+ * to verion 4.3
+ *
+ * Revision 1.3  87/03/27  14:22:21  jenkins
+ * Port to suns
+ *
+ * Revision 1.2  85/06/26  07:34:28  svb
+ * Comment leader '% ' for '*.tex' files added.
+ *
+ * Revision 4.3  83/12/15  12:26:48  wft
+ * Added check for KDELIM in filenames to pairfilenames().
+ *
+ * Revision 4.2  83/12/02  22:47:45  wft
+ * Added csh, red, and sl filename suffixes.
+ *
+ * Revision 4.1  83/05/11  16:23:39  wft
+ * Added initialization of Dbranch to InitAdmin(). Canged pairfilenames():
+ * 1. added copying of path from workfile to RCS file, if RCS file is omitted;
+ * 2. added getting the file status of RCS and working files;
+ * 3. added ignoring of directories.
+ *
+ * Revision 3.7  83/05/11  15:01:58  wft
+ * Added comtable[] which pairs filename suffixes with comment leaders;
+ * updated InitAdmin() accordingly.
+ *
+ * Revision 3.6  83/04/05  14:47:36  wft
+ * fixed Suffix in InitAdmin().
+ *
+ * Revision 3.5  83/01/17  18:01:04  wft
+ * Added getwd() and rename(); these can be removed by defining
+ * V4_2BSD, since they are not needed in 4.2 bsd.
+ * Changed sys/param.h to sys/types.h.
+ *
+ * Revision 3.4  82/12/08  21:55:20  wft
+ * removed unused variable.
+ *
+ * Revision 3.3  82/11/28  20:31:37  wft
+ * Changed mktempfile() to store the generated filenames.
+ * Changed getfullRCSname() to store the file and pathname, and to
+ * delete leading "../" and "./".
+ *
+ * Revision 3.2  82/11/12  14:29:40  wft
+ * changed pairfilenames() to handle file.sfx,v; also deleted checkpathnosfx(),
+ * checksuffix(), checkfullpath(). Semaphore name generation updated.
+ * mktempfile() now checks for nil path; freefilename initialized properly.
+ * Added Suffix .h to InitAdmin. Added testprogram PAIRTEST.
+ * Moved rmsema, trysema, trydiraccess, getfullRCSname from rcsutil.c to here.
+ *
+ * Revision 3.1  82/10/18  14:51:28  wft
+ * InitAdmin() now initializes StrictLocks=STRICT_LOCKING (def. in rcsbase.h).
+ * renamed checkpath() to checkfullpath().
+ */
+
+
+#include "rcsbase.h"
+
+libId(fnmsId, "$FreeBSD$")
+
+static char const *bindex P((char const*,int));
+static int fin2open P((char const*, size_t, char const*, size_t, char const*, size_t, RILE*(*)P((struct buf*,struct stat*,int)), int));
+static int finopen P((RILE*(*)P((struct buf*,struct stat*,int)), int));
+static int suffix_matches P((char const*,char const*));
+static size_t dir_useful_len P((char const*));
+static size_t suffixlen P((char const*));
+static void InitAdmin P((void));
+
+char const *RCSname;
+char *workname;
+int fdlock;
+FILE *workstdout;
+struct stat RCSstat;
+char const *suffixes;
+
+static char const rcsdir[] = "RCS";
+#define rcslen (sizeof(rcsdir)-1)
+
+static struct buf RCSbuf, RCSb;
+static int RCSerrno;
+
+
+/* Temp names to be unlinked when done, if they are not 0.  */
+#define TEMPNAMES 5 /* must be at least DIRTEMPNAMES (see rcsedit.c) */
+static char *volatile tpnames[TEMPNAMES];
+
+
+struct compair {
+	char const *suffix, *comlead;
+};
+
+/*
+* This table is present only for backwards compatibility.
+* Normally we ignore this table, and use the prefix of the `$Log' line instead.
+*/
+static struct compair const comtable[] = {
+	{ "a"	, "-- "	},	/* Ada */
+	{ "ada"	, "-- "	},
+	{ "adb"	, "-- "	},
+	{ "ads"	, "-- "	},
+	{ "asm"	, ";; "	},	/* assembler (MS-DOS) */
+	{ "bat"	, ":: "	},	/* batch (MS-DOS) */
+	{ "body", "-- "	},	/* Ada */
+	{ "c"	, " * "	},	/* C */
+	{ "c++"	, "// "	},	/* C++ in all its infinite guises */
+	{ "cc"	, "// "	},
+	{ "cpp"	, "// "	},
+	{ "cxx"	, "// "	},
+	{ "cl"	, ";;; "},	/* Common Lisp */
+	{ "cmd"	, ":: "	},	/* command (OS/2) */
+	{ "cmf"	, "c "	},	/* CM Fortran */
+	{ "cs"	, " * "	},	/* C* */
+	{ "el"	, "; "	},	/* Emacs Lisp */
+	{ "f"	, "c "	},	/* Fortran */
+	{ "for"	, "c "	},
+	{ "h"	, " * "	},	/* C-header */
+	{ "hpp"	, "// "	},	/* C++ header */
+	{ "hxx"	, "// "	},
+	{ "l"	, " * "	},	/* lex (NOTE: franzlisp disagrees) */
+	{ "lisp", ";;; "},	/* Lucid Lisp */
+	{ "lsp"	, ";; "	},	/* Microsoft Lisp */
+	{ "m"   , "// " },	/* Objective C */
+	{ "mac"	, ";; "	},	/* macro (DEC-10, MS-DOS, PDP-11, VMS, etc) */
+	{ "me"	, ".\\\" "},	/* troff -me */
+	{ "ml"	, "; "	},	/* mocklisp */
+	{ "mm"	, ".\\\" "},	/* troff -mm */
+	{ "ms"	, ".\\\" "},	/* troff -ms */
+	{ "p"	, " * "	},	/* Pascal */
+	{ "pas"	, " * "	},
+	{ "ps"	, "% "	},	/* PostScript */
+	{ "spec", "-- "	},	/* Ada */
+	{ "sty"	, "% "	},	/* LaTeX style */
+	{ "tex"	, "% "	},	/* TeX */
+	{ "y"	, " * "	},	/* yacc */
+	{ 0	, "# "	}	/* default for unknown suffix; must be last */
+};
+
+#if has_mktemp
+	static char const *tmp P((void));
+	static char const *
+tmp()
+/* Yield the name of the tmp directory.  */
+{
+	static char const *s;
+	if (!s
+		&&  !(s = cgetenv("TMPDIR"))	/* Unix tradition */
+		&&  !(s = cgetenv("TMP"))	/* DOS tradition */
+		&&  !(s = cgetenv("TEMP"))	/* another DOS tradition */
+	)
+		s = TMPDIR;
+	return s;
+}
+#endif
+
+	char const *
+maketemp(n)
+	int n;
+/* Create a unique pathname using n and the process id and store it
+ * into the nth slot in tpnames.
+ * Because of storage in tpnames, tempunlink() can unlink the file later.
+ * Return a pointer to the pathname created.
+ */
+{
+	char *p;
+	char const *t = tpnames[n];
+#	if has_mktemp
+	int fd;
+#	endif
+
+	if (t)
+		return t;
+
+	catchints();
+	{
+#	if has_mktemp
+	    char const *tp = tmp();
+	    size_t tplen = dir_useful_len(tp);
+	    p = testalloc(tplen + 10);
+	    VOID sprintf(p, "%.*s%cT%cXXXXXX", (int)tplen, tp, SLASH, '0'+n);
+	    fd = mkstemp(p);
+	    if (fd < 0 || !*p)
+		faterror("can't make temporary pathname `%.*s%cT%cXXXXXX'",
+			(int)tplen, tp, SLASH, '0'+n
+		);
+	    close(fd);
+#	else
+	    static char tpnamebuf[TEMPNAMES][L_tmpnam];
+	    p = tpnamebuf[n];
+	    if (!tmpnam(p) || !*p)
+#		ifdef P_tmpdir
+		    faterror("can't make temporary pathname `%s...'",P_tmpdir);
+#		else
+		    faterror("can't make temporary pathname");
+#		endif
+#	endif
+	}
+
+	tpnames[n] = p;
+	return p;
+}
+
+	void
+tempunlink()
+/* Clean up maketemp() files.  May be invoked by signal handler.
+ */
+{
+	register int i;
+	register char *p;
+
+	for (i = TEMPNAMES;  0 <= --i;  )
+	    if ((p = tpnames[i])) {
+		VOID unlink(p);
+		/*
+		 * We would tfree(p) here,
+		 * but this might dump core if we're handing a signal.
+		 * We're about to exit anyway, so we won't bother.
+		 */
+		tpnames[i] = 0;
+	    }
+}
+
+
+	static char const *
+bindex(sp, c)
+	register char const *sp;
+	register int c;
+/* Function: Finds the last occurrence of character c in string sp
+ * and returns a pointer to the character just beyond it. If the
+ * character doesn't occur in the string, sp is returned.
+ */
+{
+	register char const *r;
+        r = sp;
+        while (*sp) {
+                if (*sp++ == c) r=sp;
+        }
+        return r;
+}
+
+
+
+	static int
+suffix_matches(suffix, pattern)
+	register char const *suffix, *pattern;
+{
+	register int c;
+	if (!pattern)
+		return true;
+	for (;;)
+		switch (*suffix++ - (c = *pattern++)) {
+		    case 0:
+			if (!c)
+				return true;
+			break;
+
+		    case 'A'-'a':
+			if (ctab[c] == Letter)
+				break;
+			/* fall into */
+		    default:
+			return false;
+		}
+}
+
+
+	static void
+InitAdmin()
+/* function: initializes an admin node */
+{
+	register char const *Suffix;
+        register int i;
+
+	Head=0; Dbranch=0; AccessList=0; Symbols=0; Locks=0;
+        StrictLocks=STRICT_LOCKING;
+
+        /* guess the comment leader from the suffix*/
+	Suffix = bindex(workname, '.');
+	if (Suffix==workname) Suffix= ""; /* empty suffix; will get default*/
+	for (i=0; !suffix_matches(Suffix,comtable[i].suffix); i++)
+		continue;
+	Comment.string = comtable[i].comlead;
+	Comment.size = strlen(comtable[i].comlead);
+	Expand = KEYVAL_EXPAND;
+	clear_buf(&Ignored);
+	Lexinit(); /* note: if !finptr, reads nothing; only initializes */
+}
+
+
+
+	void
+bufalloc(b, size)
+	register struct buf *b;
+	size_t size;
+/* Ensure *B is a name buffer of at least SIZE bytes.
+ * *B's old contents can be freed; *B's new contents are undefined.
+ */
+{
+	if (b->size < size) {
+		if (b->size)
+			tfree(b->string);
+		else
+			b->size = sizeof(malloc_type);
+		while (b->size < size)
+			b->size <<= 1;
+		b->string = tnalloc(char, b->size);
+	}
+}
+
+	void
+bufrealloc(b, size)
+	register struct buf *b;
+	size_t size;
+/* like bufalloc, except *B's old contents, if any, are preserved */
+{
+	if (b->size < size) {
+		if (!b->size)
+			bufalloc(b, size);
+		else {
+			while ((b->size <<= 1)  <  size)
+				continue;
+			b->string = trealloc(char, b->string, b->size);
+		}
+	}
+}
+
+	void
+bufautoend(b)
+	struct buf *b;
+/* Free an auto buffer at block exit. */
+{
+	if (b->size)
+		tfree(b->string);
+}
+
+	struct cbuf
+bufremember(b, s)
+	struct buf *b;
+	size_t s;
+/*
+ * Free the buffer B with used size S.
+ * Yield a cbuf with identical contents.
+ * The cbuf will be reclaimed when this input file is finished.
+ */
+{
+	struct cbuf cb;
+
+	if ((cb.size = s))
+		cb.string = fremember(trealloc(char, b->string, s));
+	else {
+		bufautoend(b); /* not really auto */
+		cb.string = "";
+	}
+	return cb;
+}
+
+	char *
+bufenlarge(b, alim)
+	register struct buf *b;
+	char const **alim;
+/* Make *B larger.  Set *ALIM to its new limit, and yield the relocated value
+ * of its old limit.
+ */
+{
+	size_t s = b->size;
+	bufrealloc(b, s + 1);
+	*alim = b->string + b->size;
+	return b->string + s;
+}
+
+	void
+bufscat(b, s)
+	struct buf *b;
+	char const *s;
+/* Concatenate S to B's end. */
+{
+	size_t blen  =  b->string ? strlen(b->string) : 0;
+	bufrealloc(b, blen+strlen(s)+1);
+	VOID strcpy(b->string+blen, s);
+}
+
+	void
+bufscpy(b, s)
+	struct buf *b;
+	char const *s;
+/* Copy S into B. */
+{
+	bufalloc(b, strlen(s)+1);
+	VOID strcpy(b->string, s);
+}
+
+
+	char const *
+basefilename(p)
+	char const *p;
+/* Yield the address of the base filename of the pathname P.  */
+{
+	register char const *b = p, *q = p;
+	for (;;)
+	    switch (*q++) {
+		case SLASHes: b = q; break;
+		case 0: return b;
+	    }
+}
+
+
+	static size_t
+suffixlen(x)
+	char const *x;
+/* Yield the length of X, an RCS pathname suffix.  */
+{
+	register char const *p;
+
+	p = x;
+	for (;;)
+	    switch (*p) {
+		case 0: case SLASHes:
+		    return p - x;
+
+		default:
+		    ++p;
+		    continue;
+	    }
+}
+
+	char const *
+rcssuffix(name)
+	char const *name;
+/* Yield the suffix of NAME if it is an RCS pathname, 0 otherwise.  */
+{
+	char const *x, *p, *nz;
+	size_t nl, xl;
+
+	nl = strlen(name);
+	nz = name + nl;
+	x = suffixes;
+	do {
+	    if ((xl = suffixlen(x))) {
+		if (xl <= nl  &&  memcmp(p = nz-xl, x, xl) == 0)
+		    return p;
+	    } else
+		for (p = name;  p < nz - rcslen;  p++)
+		    if (
+			isSLASH(p[rcslen])
+			&& (p==name || isSLASH(p[-1]))
+			&& memcmp(p, rcsdir, rcslen) == 0
+		    )
+			return nz;
+	    x += xl;
+	} while (*x++);
+	return 0;
+}
+
+	/*ARGSUSED*/ RILE *
+rcsreadopen(RCSpath, status, mustread)
+	struct buf *RCSpath;
+	struct stat *status;
+	int mustread;
+/* Open RCSPATH for reading and yield its FILE* descriptor.
+ * If successful, set *STATUS to its status.
+ * Pass this routine to pairnames() for read-only access to the file.  */
+{
+	return Iopen(RCSpath->string, FOPEN_RB, status);
+}
+
+	static int
+finopen(rcsopen, mustread)
+	RILE *(*rcsopen)P((struct buf*,struct stat*,int));
+	int mustread;
+/*
+ * Use RCSOPEN to open an RCS file; MUSTREAD is set if the file must be read.
+ * Set finptr to the result and yield true if successful.
+ * RCSb holds the file's name.
+ * Set RCSbuf to the best RCS name found so far, and RCSerrno to its errno.
+ * Yield true if successful or if an unusual failure.
+ */
+{
+	int interesting, preferold;
+
+	/*
+	 * We prefer an old name to that of a nonexisting new RCS file,
+	 * unless we tried locking the old name and failed.
+	 */
+	preferold  =  RCSbuf.string[0] && (mustread||0<=fdlock);
+
+	finptr = (*rcsopen)(&RCSb, &RCSstat, mustread);
+	interesting = finptr || errno!=ENOENT;
+	if (interesting || !preferold) {
+		/* Use the new name.  */
+		RCSerrno = errno;
+		bufscpy(&RCSbuf, RCSb.string);
+	}
+	return interesting;
+}
+
+	static int
+fin2open(d, dlen, base, baselen, x, xlen, rcsopen, mustread)
+	char const *d, *base, *x;
+	size_t dlen, baselen, xlen;
+	RILE *(*rcsopen)P((struct buf*,struct stat*,int));
+	int mustread;
+/*
+ * D is a directory name with length DLEN (including trailing slash).
+ * BASE is a filename with length BASELEN.
+ * X is an RCS pathname suffix with length XLEN.
+ * Use RCSOPEN to open an RCS file; MUSTREAD is set if the file must be read.
+ * Yield true if successful.
+ * Try dRCS/basex first; if that fails and x is nonempty, try dbasex.
+ * Put these potential names in RCSb.
+ * Set RCSbuf to the best RCS name found so far, and RCSerrno to its errno.
+ * Yield true if successful or if an unusual failure.
+ */
+{
+	register char *p;
+
+	bufalloc(&RCSb, dlen + rcslen + 1 + baselen + xlen + 1);
+
+	/* Try dRCS/basex.  */
+	VOID memcpy(p = RCSb.string, d, dlen);
+	VOID memcpy(p += dlen, rcsdir, rcslen);
+	p += rcslen;
+	*p++ = SLASH;
+	VOID memcpy(p, base, baselen);
+	VOID memcpy(p += baselen, x, xlen);
+	p[xlen] = 0;
+	if (xlen) {
+	    if (finopen(rcsopen, mustread))
+		return true;
+
+	    /* Try dbasex.  */
+	    /* Start from scratch, because finopen() may have changed RCSb.  */
+	    VOID memcpy(p = RCSb.string, d, dlen);
+	    VOID memcpy(p += dlen, base, baselen);
+	    VOID memcpy(p += baselen, x, xlen);
+	    p[xlen] = 0;
+	}
+	return finopen(rcsopen, mustread);
+}
+
+	int
+pairnames(argc, argv, rcsopen, mustread, quiet)
+	int argc;
+	char **argv;
+	RILE *(*rcsopen)P((struct buf*,struct stat*,int));
+	int mustread, quiet;
+/*
+ * Pair the pathnames pointed to by argv; argc indicates
+ * how many there are.
+ * Place a pointer to the RCS pathname into RCSname,
+ * and a pointer to the pathname of the working file into workname.
+ * If both are given, and workstdout
+ * is set, a warning is printed.
+ *
+ * If the RCS file exists, places its status into RCSstat.
+ *
+ * If the RCS file exists, it is RCSOPENed for reading, the file pointer
+ * is placed into finptr, and the admin-node is read in; returns 1.
+ * If the RCS file does not exist and MUSTREAD,
+ * print an error unless QUIET and return 0.
+ * Otherwise, initialize the admin node and return -1.
+ *
+ * 0 is returned on all errors, e.g. files that are not regular files.
+ */
+{
+	static struct buf tempbuf;
+
+	register char *p, *arg, *RCS1;
+	char const *base, *RCSbase, *x;
+	int paired;
+	size_t arglen, dlen, baselen, xlen;
+
+	fdlock = -1;
+
+	if (!(arg = *argv)) return 0; /* already paired pathname */
+	if (*arg == '-') {
+		error("%s option is ignored after pathnames", arg);
+		return 0;
+	}
+
+	base = basefilename(arg);
+	paired = false;
+
+        /* first check suffix to see whether it is an RCS file or not */
+	if ((x = rcssuffix(arg)))
+	{
+		/* RCS pathname given */
+		RCS1 = arg;
+		RCSbase = base;
+		baselen = x - base;
+		if (
+		    1 < argc  &&
+		    !rcssuffix(workname = p = argv[1])  &&
+		    baselen <= (arglen = strlen(p))  &&
+		    ((p+=arglen-baselen) == workname  ||  isSLASH(p[-1])) &&
+		    memcmp(base, p, baselen) == 0
+		) {
+			argv[1] = 0;
+			paired = true;
+		} else {
+			bufscpy(&tempbuf, base);
+			workname = p = tempbuf.string;
+			p[baselen] = 0;
+		}
+        } else {
+                /* working file given; now try to find RCS file */
+		workname = arg;
+		baselen = strlen(base);
+		/* Derive RCS pathname.  */
+		if (
+		    1 < argc  &&
+		    (x = rcssuffix(RCS1 = argv[1]))  &&
+		    baselen  <=  x - RCS1  &&
+		    ((RCSbase=x-baselen)==RCS1 || isSLASH(RCSbase[-1])) &&
+		    memcmp(base, RCSbase, baselen) == 0
+		) {
+			argv[1] = 0;
+			paired = true;
+		} else
+			RCSbase = RCS1 = 0;
+        }
+	/* Now we have a (tentative) RCS pathname in RCS1 and workname.  */
+        /* Second, try to find the right RCS file */
+	if (RCSbase!=RCS1) {
+                /* a path for RCSfile is given; single RCS file to look for */
+		bufscpy(&RCSbuf, RCS1);
+		finptr = (*rcsopen)(&RCSbuf, &RCSstat, mustread);
+		RCSerrno = errno;
+        } else {
+		bufscpy(&RCSbuf, "");
+		if (RCS1)
+			/* RCS filename was given without path.  */
+			VOID fin2open(arg, (size_t)0, RCSbase, baselen,
+				x, strlen(x), rcsopen, mustread
+			);
+		else {
+			/* No RCS pathname was given.  */
+			/* Try each suffix in turn.  */
+			dlen = base-arg;
+			x = suffixes;
+			while (! fin2open(arg, dlen, base, baselen,
+					x, xlen=suffixlen(x), rcsopen, mustread
+			)) {
+				x += xlen;
+				if (!*x++)
+					break;
+			}
+		}
+        }
+	RCSname = p = RCSbuf.string;
+	if (finptr) {
+		if (!S_ISREG(RCSstat.st_mode)) {
+			error("%s isn't a regular file -- ignored", p);
+                        return 0;
+                }
+                Lexinit(); getadmin();
+	} else {
+		if (RCSerrno!=ENOENT || mustread || fdlock<0) {
+			if (RCSerrno == EEXIST)
+				error("RCS file %s is in use", p);
+			else if (!quiet || RCSerrno!=ENOENT)
+				enerror(RCSerrno, p);
+			return 0;
+		}
+                InitAdmin();
+        };
+
+	if (paired && workstdout)
+		workwarn("Working file ignored due to -p option");
+
+	prevkeys = false;
+	return finptr ? 1 : -1;
+}
+
+
+	char const *
+getfullRCSname()
+/*
+ * Return a pointer to the full pathname of the RCS file.
+ * Remove leading `./'.
+ */
+{
+	if (ROOTPATH(RCSname)) {
+	    return RCSname;
+	} else {
+	    static struct buf rcsbuf;
+#	    if needs_getabsname
+		bufalloc(&rcsbuf, SIZEABLE_PATH + 1);
+		while (getabsname(RCSname, rcsbuf.string, rcsbuf.size) != 0)
+		    if (errno == ERANGE)
+			bufalloc(&rcsbuf, rcsbuf.size<<1);
+		    else
+			efaterror("getabsname");
+#	    else
+		static char const *wdptr;
+		static struct buf wdbuf;
+		static size_t wdlen;
+
+		register char const *r;
+		register size_t dlen;
+		register char *d;
+		register char const *wd;
+
+		if (!(wd = wdptr)) {
+		    /* Get working directory for the first time.  */
+		    char *PWD = cgetenv("PWD");
+		    struct stat PWDstat, dotstat;
+		    if (! (
+			(d = PWD) &&
+			ROOTPATH(PWD) &&
+			stat(PWD, &PWDstat) == 0 &&
+			stat(".", &dotstat) == 0 &&
+			same_file(PWDstat, dotstat, 1)
+		    )) {
+			bufalloc(&wdbuf, SIZEABLE_PATH + 1);
+#			if has_getcwd || !has_getwd
+			    while (!(d = getcwd(wdbuf.string, wdbuf.size)))
+				if (errno == ERANGE)
+				    bufalloc(&wdbuf, wdbuf.size<<1);
+				else if ((d = PWD))
+				    break;
+				else
+				    efaterror("getcwd");
+#			else
+			    d = getwd(wdbuf.string);
+			    if (!d  &&  !(d = PWD))
+				efaterror("getwd");
+#			endif
+		    }
+		    wdlen = dir_useful_len(d);
+		    d[wdlen] = 0;
+		    wdptr = wd = d;
+                }
+		/*
+		* Remove leading `./'s from RCSname.
+		* Do not try to handle `../', since removing it may yield
+		* the wrong answer in the presence of symbolic links.
+		*/
+		for (r = RCSname;  r[0]=='.' && isSLASH(r[1]);  r += 2)
+		    /* `.////' is equivalent to `./'.  */
+		    while (isSLASH(r[2]))
+			r++;
+		/* Build full pathname.  */
+		dlen = wdlen;
+		bufalloc(&rcsbuf, dlen + strlen(r) + 2);
+		d = rcsbuf.string;
+		VOID memcpy(d, wd, dlen);
+		d += dlen;
+		*d++ = SLASH;
+		VOID strcpy(d, r);
+#	    endif
+	    return rcsbuf.string;
+        }
+}
+
+/* Derived from code from the XFree86 project */
+	char const *
+getfullCVSname()
+/* Function: returns a pointer to the path name of the RCS file with the
+ * CVSROOT part stripped off, and with 'Attic/' stripped off (if present).
+ */
+{
+
+#define ATTICDIR "/Attic"
+
+	char const *namebuf = getfullRCSname();
+	char *cvsroot = cgetenv("CVSROOT");
+	int cvsrootlen;
+	char *c = NULL;
+	int alen = strlen(ATTICDIR);
+
+	if ((c = strrchr(namebuf, '/')) != NULL) {
+	    if (namebuf - c >= alen) {
+		if (!strncmp(c - alen, ATTICDIR, alen)) {
+		    while(*c != '\0') {
+			*(c - alen) = *c;
+			c++;
+		    }
+		    *(c - alen) = '\0';
+		}
+	    }
+	}
+	
+	if (!cvsroot)
+	    return(namebuf);
+	else
+	{
+	    cvsrootlen = strlen(cvsroot);
+	    if (!strncmp(namebuf, cvsroot, cvsrootlen) &&
+	        namebuf[cvsrootlen] == '/')
+		return(namebuf + cvsrootlen + 1);
+	    else
+		return(namebuf);
+	}
+}
+
+	static size_t
+dir_useful_len(d)
+	char const *d;
+/*
+* D names a directory; yield the number of characters of D's useful part.
+* To create a file in D, append a SLASH and a file name to D's useful part.
+* Ignore trailing slashes if possible; not only are they ugly,
+* but some non-Posix systems misbehave unless the slashes are omitted.
+*/
+{
+#	ifndef SLASHSLASH_is_SLASH
+#	define SLASHSLASH_is_SLASH 0
+#	endif
+	size_t dlen = strlen(d);
+	if (!SLASHSLASH_is_SLASH && dlen==2 && isSLASH(d[0]) && isSLASH(d[1]))
+	    --dlen;
+	else
+	    while (dlen && isSLASH(d[dlen-1]))
+		--dlen;
+	return dlen;
+}
+
+#ifndef isSLASH
+	int
+isSLASH(c)
+	int c;
+{
+	switch (c) {
+	    case SLASHes:
+		return true;
+	    default:
+		return false;
+	}
+}
+#endif
+
+
+#if !has_getcwd && !has_getwd
+
+	char *
+getcwd(path, size)
+	char *path;
+	size_t size;
+{
+	static char const usrbinpwd[] = "/usr/bin/pwd";
+#	define binpwd (usrbinpwd+4)
+
+	register FILE *fp;
+	register int c;
+	register char *p, *lim;
+	int closeerrno, closeerror, e, fd[2], readerror, toolong, wstatus;
+	pid_t child;
+
+	if (!size) {
+		errno = EINVAL;
+		return 0;
+	}
+	if (pipe(fd) != 0)
+		return 0;
+#	if bad_wait_if_SIGCHLD_ignored
+#		ifndef SIGCHLD
+#		define SIGCHLD SIGCLD
+#		endif
+		VOID signal(SIGCHLD, SIG_DFL);
+#	endif
+	if (!(child = vfork())) {
+		if (
+			close(fd[0]) == 0 &&
+			(fd[1] == STDOUT_FILENO ||
+#				ifdef F_DUPFD
+					(VOID close(STDOUT_FILENO),
+					fcntl(fd[1], F_DUPFD, STDOUT_FILENO))
+#				else
+					dup2(fd[1], STDOUT_FILENO)
+#				endif
+				== STDOUT_FILENO &&
+				close(fd[1]) == 0
+			)
+		) {
+			VOID close(STDERR_FILENO);
+			VOID execl(binpwd, binpwd, (char *)0);
+			VOID execl(usrbinpwd, usrbinpwd, (char *)0);
+		}
+		_exit(EXIT_FAILURE);
+	}
+	e = errno;
+	closeerror = close(fd[1]);
+	closeerrno = errno;
+	fp = 0;
+	readerror = toolong = wstatus = 0;
+	p = path;
+	if (0 <= child) {
+		fp = fdopen(fd[0], "r");
+		e = errno;
+		if (fp) {
+			lim = p + size;
+			for (p = path;  ;  *p++ = c) {
+				if ((c=getc(fp)) < 0) {
+					if (feof(fp))
+						break;
+					if (ferror(fp)) {
+						readerror = 1;
+						e = errno;
+						break;
+					}
+				}
+				if (p == lim) {
+					toolong = 1;
+					break;
+				}
+			}
+		}
+#		if has_waitpid
+			if (waitpid(child, &wstatus, 0) < 0)
+				wstatus = 1;
+#		else
+			{
+				pid_t w;
+				do {
+					if ((w = wait(&wstatus)) < 0) {
+						wstatus = 1;
+						break;
+					}
+				} while (w != child);
+			}
+#		endif
+	}
+	if (!fp) {
+		VOID close(fd[0]);
+		errno = e;
+		return 0;
+	}
+	if (fclose(fp) != 0)
+		return 0;
+	if (readerror) {
+		errno = e;
+		return 0;
+	}
+	if (closeerror) {
+		errno = closeerrno;
+		return 0;
+	}
+	if (toolong) {
+		errno = ERANGE;
+		return 0;
+	}
+	if (wstatus  ||  p == path  ||  *--p != '\n') {
+		errno = EACCES;
+		return 0;
+	}
+	*p = '\0';
+	return path;
+}
+#endif
+
+
+#ifdef PAIRTEST
+/* test program for pairnames() and getfullRCSname() */
+
+char const cmdid[] = "pair";
+
+main(argc, argv)
+int argc; char *argv[];
+{
+        int result;
+	int initflag;
+	quietflag = initflag = false;
+
+        while(--argc, ++argv, argc>=1 && ((*argv)[0] == '-')) {
+                switch ((*argv)[1]) {
+
+		case 'p':       workstdout = stdout;
+                                break;
+                case 'i':       initflag=true;
+                                break;
+                case 'q':       quietflag=true;
+                                break;
+                default:        error("unknown option: %s", *argv);
+                                break;
+                }
+        }
+
+        do {
+		RCSname = workname = 0;
+		result = pairnames(argc,argv,rcsreadopen,!initflag,quietflag);
+                if (result!=0) {
+		    diagnose("RCS pathname: %s; working pathname: %s\nFull RCS pathname: %s\n",
+			     RCSname, workname, getfullRCSname()
+		    );
+                }
+                switch (result) {
+                        case 0: continue; /* already paired file */
+
+                        case 1: if (initflag) {
+				    rcserror("already exists");
+                                } else {
+				    diagnose("RCS file %s exists\n", RCSname);
+                                }
+				Ifclose(finptr);
+                                break;
+
+			case -1:diagnose("RCS file doesn't exist\n");
+                                break;
+                }
+
+        } while (++argv, --argc>=1);
+
+}
+
+	void
+exiterr()
+{
+	dirtempunlink();
+	tempunlink();
+	_exit(EXIT_FAILURE);
+}
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcsgen.c b/gnu/usr.bin/rcs/lib/rcsgen.c
new file mode 100644
index 0000000000000..35d8702a34f84
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsgen.c
@@ -0,0 +1,681 @@
+/* Generate RCS revisions.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.16  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.15  1995/06/01 16:23:43  eggert
+ * (putadmin): Open RCS file with FOPEN_WB.
+ *
+ * Revision 5.14  1994/03/17 14:05:48  eggert
+ * Work around SVR4 stdio performance bug.
+ * Flush stderr after prompt.  Remove lint.
+ *
+ * Revision 5.13  1993/11/03 17:42:27  eggert
+ * Don't discard ignored phrases.  Improve quality of diagnostics.
+ *
+ * Revision 5.12  1992/07/28  16:12:44  eggert
+ * Statement macro names now end in _.
+ * Be consistent about pathnames vs filenames.
+ *
+ * Revision 5.11  1992/01/24  18:44:19  eggert
+ * Move put routines here from rcssyn.c.
+ * Add support for bad_creat0.
+ *
+ * Revision 5.10  1991/10/07  17:32:46  eggert
+ * Fix log bugs, e.g. ci -t/dev/null when has_mmap.
+ *
+ * Revision 5.9  1991/09/10  22:15:46  eggert
+ * Fix test for redirected stdin.
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Add piece tables.  Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:24  eggert
+ * Add MS-DOS support.
+ *
+ * Revision 5.6  1990/12/27  19:54:26  eggert
+ * Fix bug: rcs -t inserted \n, making RCS file grow.
+ *
+ * Revision 5.5  1990/12/04  05:18:45  eggert
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.4  1990/11/01  05:03:47  eggert
+ * Add -I and new -t behavior.  Permit arbitrary data in logs.
+ *
+ * Revision 5.3  1990/09/21  06:12:43  hammer
+ * made putdesc() treat stdin the same whether or not it was from a terminal
+ * by making it recognize that a single '.' was then end of the
+ * description always
+ *
+ * Revision 5.2  1990/09/04  08:02:25  eggert
+ * Fix `co -p1.1 -ko' bug.  Standardize yes-or-no procedure.
+ *
+ * Revision 5.1  1990/08/29  07:14:01  eggert
+ * Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:12:52  eggert
+ * Remove compile-time limits; use malloc instead.
+ * Ansify and Posixate.
+ *
+ * Revision 4.7  89/05/01  15:12:49  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.6  88/08/28  14:59:10  eggert
+ * Shrink stdio code size; allow cc -R; remove lint; isatty() -> ttystdin()
+ *
+ * Revision 4.5  87/12/18  11:43:25  narten
+ * additional lint cleanups, and a bug fix from the 4.3BSD version that
+ * keeps "ci" from sticking a '\377' into the description if you run it
+ * with a zero-length file as the description. (Guy Harris)
+ *
+ * Revision 4.4  87/10/18  10:35:10  narten
+ * Updating version numbers. Changes relative to 1.1 actually relative to
+ * 4.2
+ *
+ * Revision 1.3  87/09/24  13:59:51  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:27  jenkins
+ * Port to suns
+ *
+ * Revision 4.2  83/12/02  23:01:39  wft
+ * merged 4.1 and 3.3.1.1 (clearerr(stdin)).
+ *
+ * Revision 4.1  83/05/10  16:03:33  wft
+ * Changed putamin() to abort if trying to reread redirected stdin.
+ * Fixed getdesc() to output a prompt on initial newline.
+ *
+ * Revision 3.3.1.1  83/10/19  04:21:51  lepreau
+ * Added clearerr(stdin) for re-reading description from stdin.
+ *
+ * Revision 3.3  82/11/28  21:36:49  wft
+ * 4.2 prerelease
+ *
+ * Revision 3.3  82/11/28  21:36:49  wft
+ * Replaced ferror() followed by fclose() with ffclose().
+ * Putdesc() now suppresses the prompts if stdin
+ * is not a terminal. A pointer to the current log message is now
+ * inserted into the corresponding delta, rather than leaving it in a
+ * global variable.
+ *
+ * Revision 3.2  82/10/18  21:11:26  wft
+ * I added checks for write errors during editing, and improved
+ * the prompt on putdesc().
+ *
+ * Revision 3.1  82/10/13  15:55:09  wft
+ * corrected type of variables assigned to by getc (char --> int)
+ */
+
+
+
+
+#include "rcsbase.h"
+
+libId(genId, "$FreeBSD$")
+
+int interactiveflag;  /* Should we act as if stdin is a tty?  */
+struct buf curlogbuf;  /* buffer for current log message */
+
+enum stringwork { enter, copy, edit, expand, edit_expand };
+
+static void putdelta P((struct hshentry const*,FILE*));
+static void scandeltatext P((struct hshentry*,enum stringwork,int));
+
+
+
+
+	char const *
+buildrevision(deltas, target, outfile, expandflag)
+	struct hshentries const *deltas;
+	struct hshentry *target;
+	FILE *outfile;
+	int expandflag;
+/* Function: Generates the revision given by target
+ * by retrieving all deltas given by parameter deltas and combining them.
+ * If outfile is set, the revision is output to it,
+ * otherwise written into a temporary file.
+ * Temporary files are allocated by maketemp().
+ * if expandflag is set, keyword expansion is performed.
+ * Return 0 if outfile is set, the name of the temporary file otherwise.
+ *
+ * Algorithm: Copy initial revision unchanged.  Then edit all revisions but
+ * the last one into it, alternating input and output files (resultname and
+ * editname). The last revision is then edited in, performing simultaneous
+ * keyword substitution (this saves one extra pass).
+ * All this simplifies if only one revision needs to be generated,
+ * or no keyword expansion is necessary, or if output goes to stdout.
+ */
+{
+	if (deltas->first == target) {
+                /* only latest revision to generate */
+		openfcopy(outfile);
+		scandeltatext(target, expandflag?expand:copy, true);
+		if (outfile)
+			return 0;
+		else {
+			Ozclose(&fcopy);
+			return resultname;
+		}
+        } else {
+                /* several revisions to generate */
+		/* Get initial revision without keyword expansion.  */
+		scandeltatext(deltas->first, enter, false);
+		while ((deltas=deltas->rest)->rest) {
+                        /* do all deltas except last one */
+			scandeltatext(deltas->first, edit, false);
+                }
+		if (expandflag || outfile) {
+                        /* first, get to beginning of file*/
+			finishedit((struct hshentry*)0, outfile, false);
+                }
+		scandeltatext(target, expandflag?edit_expand:edit, true);
+		finishedit(
+			expandflag ? target : (struct hshentry*)0,
+			outfile, true
+		);
+		if (outfile)
+			return 0;
+		Ozclose(&fcopy);
+		return resultname;
+        }
+}
+
+
+
+	static void
+scandeltatext(delta, func, needlog)
+	struct hshentry *delta;
+	enum stringwork func;
+	int needlog;
+/* Function: Scans delta text nodes up to and including the one given
+ * by delta. For the one given by delta, the log message is saved into
+ * delta->log if needlog is set; func specifies how to handle the text.
+ * Similarly, if needlog, delta->igtext is set to the ignored phrases.
+ * Assumes the initial lexeme must be read in first.
+ * Does not advance nexttok after it is finished.
+ */
+{
+	struct hshentry const *nextdelta;
+	struct cbuf cb;
+
+        for (;;) {
+		if (eoflex())
+		    fatserror("can't find delta for revision %s", delta->num);
+                nextlex();
+                if (!(nextdelta=getnum())) {
+		    fatserror("delta number corrupted");
+                }
+		getkeystring(Klog);
+		if (needlog && delta==nextdelta) {
+			cb = savestring(&curlogbuf);
+			delta->log = cleanlogmsg(curlogbuf.string, cb.size);
+			nextlex();
+			delta->igtext = getphrases(Ktext);
+                } else {readstring();
+			ignorephrases(Ktext);
+                }
+		getkeystring(Ktext);
+
+		if (delta==nextdelta)
+			break;
+		readstring(); /* skip over it */
+
+	}
+	switch (func) {
+		case enter: enterstring(); break;
+		case copy: copystring(); break;
+		case expand: xpandstring(delta); break;
+		case edit: editstring((struct hshentry *)0); break;
+		case edit_expand: editstring(delta); break;
+	}
+}
+
+	struct cbuf
+cleanlogmsg(m, s)
+	char *m;
+	size_t s;
+{
+	register char *t = m;
+	register char const *f = t;
+	struct cbuf r;
+	while (s) {
+	    --s;
+	    if ((*t++ = *f++) == '\n')
+		while (m < --t)
+		    if (t[-1]!=' ' && t[-1]!='\t') {
+			*t++ = '\n';
+			break;
+		    }
+	}
+	while (m < t  &&  (t[-1]==' ' || t[-1]=='\t' || t[-1]=='\n'))
+	    --t;
+	r.string = m;
+	r.size = t - m;
+	return r;
+}
+
+
+int ttystdin()
+{
+	static int initialized;
+	if (!initialized) {
+		if (!interactiveflag)
+			interactiveflag = isatty(STDIN_FILENO);
+		initialized = true;
+	}
+	return interactiveflag;
+}
+
+	int
+getcstdin()
+{
+	register FILE *in;
+	register int c;
+
+	in = stdin;
+	if (feof(in) && ttystdin())
+		clearerr(in);
+	c = getc(in);
+	if (c == EOF) {
+		testIerror(in);
+		if (feof(in) && ttystdin())
+			afputc('\n',stderr);
+	}
+	return c;
+}
+
+#if has_prototypes
+	int
+yesorno(int default_answer, char const *question, ...)
+#else
+		/*VARARGS2*/ int
+	yesorno(default_answer, question, va_alist)
+		int default_answer; char const *question; va_dcl
+#endif
+{
+	va_list args;
+	register int c, r;
+	if (!quietflag && ttystdin()) {
+		oflush();
+		vararg_start(args, question);
+		fvfprintf(stderr, question, args);
+		va_end(args);
+		eflush();
+		r = c = getcstdin();
+		while (c!='\n' && !feof(stdin))
+			c = getcstdin();
+		if (r=='y' || r=='Y')
+			return true;
+		if (r=='n' || r=='N')
+			return false;
+	}
+	return default_answer;
+}
+
+
+	void
+putdesc(textflag, textfile)
+	int textflag;
+	char *textfile;
+/* Function: puts the descriptive text into file frewrite.
+ * if finptr && !textflag, the text is copied from the old description.
+ * Otherwise, if textfile, the text is read from that
+ * file, or from stdin, if !textfile.
+ * A textfile with a leading '-' is treated as a string, not a pathname.
+ * If finptr, the old descriptive text is discarded.
+ * Always clears foutptr.
+ */
+{
+	static struct buf desc;
+	static struct cbuf desclean;
+
+	register FILE *txt;
+	register int c;
+	register FILE * frew;
+	register char *p;
+	register size_t s;
+	char const *plim;
+
+	frew = frewrite;
+	if (finptr && !textflag) {
+                /* copy old description */
+		aprintf(frew, "\n\n%s%c", Kdesc, nextc);
+		foutptr = frewrite;
+		getdesc(false);
+		foutptr = 0;
+        } else {
+		foutptr = 0;
+                /* get new description */
+		if (finptr) {
+                        /*skip old description*/
+			getdesc(false);
+                }
+		aprintf(frew,"\n\n%s\n%c",Kdesc,SDELIM);
+		if (!textfile)
+			desclean = getsstdin(
+				"t-", "description",
+				"NOTE: This is NOT the log message!\n", &desc
+			);
+		else if (!desclean.string) {
+			if (*textfile == '-') {
+				p = textfile + 1;
+				s = strlen(p);
+			} else {
+				if (!(txt = fopenSafer(textfile, "r")))
+					efaterror(textfile);
+				bufalloc(&desc, 1);
+				p = desc.string;
+				plim = p + desc.size;
+				for (;;) {
+					if ((c=getc(txt)) == EOF) {
+						testIerror(txt);
+						if (feof(txt))
+							break;
+					}
+					if (plim <= p)
+					    p = bufenlarge(&desc, &plim);
+					*p++ = c;
+				}
+				if (fclose(txt) != 0)
+					Ierror();
+				s = p - desc.string;
+				p = desc.string;
+			}
+			desclean = cleanlogmsg(p, s);
+		}
+		putstring(frew, false, desclean, true);
+		aputc_('\n', frew)
+        }
+}
+
+	struct cbuf
+getsstdin(option, name, note, buf)
+	char const *option, *name, *note;
+	struct buf *buf;
+{
+	register int c;
+	register char *p;
+	register size_t i;
+	register int tty = ttystdin();
+
+	if (tty) {
+	    aprintf(stderr,
+		"enter %s, terminated with single '.' or end of file:\n%s>> ",
+		name, note
+	    );
+	    eflush();
+	} else if (feof(stdin))
+	    rcsfaterror("can't reread redirected stdin for %s; use -%s<%s>",
+		name, option, name
+	    );
+
+	for (
+	   i = 0,  p = 0;
+	   c = getcstdin(),  !feof(stdin);
+	   bufrealloc(buf, i+1),  p = buf->string,  p[i++] = c
+	)
+		if (c == '\n')
+			if (i  &&  p[i-1]=='.'  &&  (i==1 || p[i-2]=='\n')) {
+				/* Remove trailing '.'.  */
+				--i;
+				break;
+			} else if (tty) {
+				aputs(">> ", stderr);
+				eflush();
+			}
+	return cleanlogmsg(p, i);
+}
+
+
+	void
+putadmin()
+/* Output the admin node.  */
+{
+	register FILE *fout;
+	struct assoc const *curassoc;
+	struct rcslock const *curlock;
+	struct access const *curaccess;
+
+	if (!(fout = frewrite)) {
+#		if bad_creat0
+			ORCSclose();
+			fout = fopenSafer(makedirtemp(0), FOPEN_WB);
+#		else
+			int fo = fdlock;
+			fdlock = -1;
+			fout = fdopen(fo, FOPEN_WB);
+#		endif
+
+		if (!(frewrite = fout))
+			efaterror(RCSname);
+	}
+
+	/*
+	* Output the first character with putc, not printf.
+	* Otherwise, an SVR4 stdio bug buffers output inefficiently.
+	*/
+	aputc_(*Khead, fout)
+	aprintf(fout, "%s\t%s;\n", Khead + 1, Head?Head->num:"");
+	if (Dbranch && VERSION(4)<=RCSversion)
+		aprintf(fout, "%s\t%s;\n", Kbranch, Dbranch);
+
+	aputs(Kaccess, fout);
+	curaccess = AccessList;
+	while (curaccess) {
+	       aprintf(fout, "\n\t%s", curaccess->login);
+	       curaccess = curaccess->nextaccess;
+	}
+	aprintf(fout, ";\n%s", Ksymbols);
+	curassoc = Symbols;
+	while (curassoc) {
+	       aprintf(fout, "\n\t%s:%s", curassoc->symbol, curassoc->num);
+	       curassoc = curassoc->nextassoc;
+	}
+	aprintf(fout, ";\n%s", Klocks);
+	curlock = Locks;
+	while (curlock) {
+	       aprintf(fout, "\n\t%s:%s", curlock->login, curlock->delta->num);
+	       curlock = curlock->nextlock;
+	}
+	if (StrictLocks) aprintf(fout, "; %s", Kstrict);
+	aprintf(fout, ";\n");
+	if (Comment.size) {
+		aprintf(fout, "%s\t", Kcomment);
+		putstring(fout, true, Comment, false);
+		aprintf(fout, ";\n");
+	}
+	if (Expand != KEYVAL_EXPAND)
+		aprintf(fout, "%s\t%c%s%c;\n",
+			Kexpand, SDELIM, expand_names[Expand], SDELIM
+		);
+	awrite(Ignored.string, Ignored.size, fout);
+	aputc_('\n', fout)
+}
+
+
+	static void
+putdelta(node, fout)
+	register struct hshentry const *node;
+	register FILE * fout;
+/* Output the delta NODE to FOUT.  */
+{
+	struct branchhead const *nextbranch;
+
+	if (!node) return;
+
+	aprintf(fout, "\n%s\n%s\t%s;\t%s %s;\t%s %s;\nbranches",
+		node->num,
+		Kdate, node->date,
+		Kauthor, node->author,
+		Kstate, node->state?node->state:""
+	);
+	nextbranch = node->branches;
+	while (nextbranch) {
+	       aprintf(fout, "\n\t%s", nextbranch->hsh->num);
+	       nextbranch = nextbranch->nextbranch;
+	}
+
+	aprintf(fout, ";\n%s\t%s;\n", Knext, node->next?node->next->num:"");
+	awrite(node->ig.string, node->ig.size, fout);
+}
+
+
+	void
+puttree(root, fout)
+	struct hshentry const *root;
+	register FILE *fout;
+/* Output the delta tree with base ROOT in preorder to FOUT.  */
+{
+	struct branchhead const *nextbranch;
+
+	if (!root) return;
+
+	if (root->selector)
+		putdelta(root, fout);
+
+	puttree(root->next, fout);
+
+	nextbranch = root->branches;
+	while (nextbranch) {
+	     puttree(nextbranch->hsh, fout);
+	     nextbranch = nextbranch->nextbranch;
+	}
+}
+
+
+	int
+putdtext(delta, srcname, fout, diffmt)
+	struct hshentry const *delta;
+	char const *srcname;
+	FILE *fout;
+	int diffmt;
+/*
+ * Output a deltatext node with delta number DELTA->num, log message DELTA->log,
+ * ignored phrases DELTA->igtext and text SRCNAME to FOUT.
+ * Double up all SDELIMs in both the log and the text.
+ * Make sure the log message ends in \n.
+ * Return false on error.
+ * If DIFFMT, also check that the text is valid diff -n output.
+ */
+{
+	RILE *fin;
+	if (!(fin = Iopen(srcname, "r", (struct stat*)0))) {
+		eerror(srcname);
+		return false;
+	}
+	putdftext(delta, fin, fout, diffmt);
+	Ifclose(fin);
+	return true;
+}
+
+	void
+putstring(out, delim, s, log)
+	register FILE *out;
+	struct cbuf s;
+	int delim, log;
+/*
+ * Output to OUT one SDELIM if DELIM, then the string S with SDELIMs doubled.
+ * If LOG is set then S is a log string; append a newline if S is nonempty.
+ */
+{
+	register char const *sp;
+	register size_t ss;
+
+	if (delim)
+		aputc_(SDELIM, out)
+	sp = s.string;
+	for (ss = s.size;  ss;  --ss) {
+		if (*sp == SDELIM)
+			aputc_(SDELIM, out)
+		aputc_(*sp++, out)
+	}
+	if (s.size && log)
+		aputc_('\n', out)
+	aputc_(SDELIM, out)
+}
+
+	void
+putdftext(delta, finfile, foutfile, diffmt)
+	struct hshentry const *delta;
+	RILE *finfile;
+	FILE *foutfile;
+	int diffmt;
+/* like putdtext(), except the source file is already open */
+{
+	declarecache;
+	register FILE *fout;
+	register int c;
+	register RILE *fin;
+	int ed;
+	struct diffcmd dc;
+
+	fout = foutfile;
+	aprintf(fout, DELNUMFORM, delta->num, Klog);
+
+	/* put log */
+	putstring(fout, true, delta->log, true);
+	aputc_('\n', fout)
+
+	/* put ignored phrases */
+	awrite(delta->igtext.string, delta->igtext.size, fout);
+
+	/* put text */
+	aprintf(fout, "%s\n%c", Ktext, SDELIM);
+
+	fin = finfile;
+	setupcache(fin);
+	if (!diffmt) {
+	    /* Copy the file */
+	    cache(fin);
+	    for (;;) {
+		cachegeteof_(c, break;)
+		if (c==SDELIM) aputc_(SDELIM, fout) /*double up SDELIM*/
+		aputc_(c, fout)
+	    }
+	} else {
+	    initdiffcmd(&dc);
+	    while (0  <=  (ed = getdiffcmd(fin, false, fout, &dc)))
+		if (ed) {
+		    cache(fin);
+		    while (dc.nlines--)
+			do {
+			    cachegeteof_(c, { if (!dc.nlines) goto OK_EOF; unexpected_EOF(); })
+			    if (c == SDELIM)
+				aputc_(SDELIM, fout)
+			    aputc_(c, fout)
+			} while (c != '\n');
+		    uncache(fin);
+		}
+	}
+    OK_EOF:
+	aprintf(fout, "%c\n", SDELIM);
+}
diff --git a/gnu/usr.bin/rcs/lib/rcskeep.c b/gnu/usr.bin/rcs/lib/rcskeep.c
new file mode 100644
index 0000000000000..4a90f851e6156
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcskeep.c
@@ -0,0 +1,452 @@
+/* Extract RCS keyword string values from working files.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.10  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.9  1995/06/01 16:23:43  eggert
+ * (getoldkeys): Don't panic if a Name: is empty.
+ *
+ * Revision 5.8  1994/03/17 14:05:48  eggert
+ * Remove lint.
+ *
+ * Revision 5.7  1993/11/09 17:40:15  eggert
+ * Use simpler timezone parsing strategy now that we're using ISO 8601 format.
+ *
+ * Revision 5.6  1993/11/03 17:42:27  eggert
+ * Scan for Name keyword.  Improve quality of diagnostics.
+ *
+ * Revision 5.5  1992/07/28  16:12:44  eggert
+ * Statement macro names now end in _.
+ *
+ * Revision 5.4  1991/08/19  03:13:55  eggert
+ * Tune.
+ *
+ * Revision 5.3  1991/04/21  11:58:25  eggert
+ * Shorten names to keep them distinct on shortname hosts.
+ *
+ * Revision 5.2  1990/10/04  06:30:20  eggert
+ * Parse time zone offsets; future RCS versions may output them.
+ *
+ * Revision 5.1  1990/09/20  02:38:56  eggert
+ * ci -k now checks dates more thoroughly.
+ *
+ * Revision 5.0  1990/08/22  08:12:53  eggert
+ * Retrieve old log message if there is one.
+ * Don't require final newline.
+ * Remove compile-time limits; use malloc instead.  Tune.
+ * Permit dates past 1999/12/31.  Ansify and Posixate.
+ *
+ * Revision 4.6  89/05/01  15:12:56  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.5  88/08/09  19:13:03  eggert
+ * Remove lint and speed up by making FILE *fp local, not global.
+ *
+ * Revision 4.4  87/12/18  11:44:21  narten
+ * more lint cleanups (Guy Harris)
+ *
+ * Revision 4.3  87/10/18  10:35:50  narten
+ * Updating version numbers. Changes relative to 1.1 actually relative
+ * to 4.1
+ *
+ * Revision 1.3  87/09/24  14:00:00  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:29  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/10  16:26:44  wft
+ * Added new markers Id and RCSfile; extraction added.
+ * Marker matching with trymatch().
+ *
+ * Revision 3.2  82/12/24  12:08:26  wft
+ * added missing #endif.
+ *
+ * Revision 3.1  82/12/04  13:22:41  wft
+ * Initial revision.
+ *
+ */
+
+#include  "rcsbase.h"
+
+libId(keepId, "$FreeBSD$")
+
+static int badly_terminated P((void));
+static int checknum P((char const*));
+static int get0val P((int,RILE*,struct buf*,int));
+static int getval P((RILE*,struct buf*,int));
+static int keepdate P((RILE*));
+static int keepid P((int,RILE*,struct buf*));
+static int keeprev P((RILE*));
+
+int prevkeys;
+struct buf prevauthor, prevdate, prevname, prevrev, prevstate;
+
+	int
+getoldkeys(fp)
+	register RILE *fp;
+/* Function: Tries to read keyword values for author, date,
+ * revision number, and state out of the file fp.
+ * If fp is null, workname is opened and closed instead of using fp.
+ * The results are placed into
+ * prevauthor, prevdate, prevname, prevrev, prevstate.
+ * Aborts immediately if it finds an error and returns false.
+ * If it returns true, it doesn't mean that any of the
+ * values were found; instead, check to see whether the corresponding arrays
+ * contain the empty string.
+ */
+{
+    register int c;
+    char keyword[keylength+1];
+    register char * tp;
+    int needs_closing;
+    int prevname_found;
+
+    if (prevkeys)
+	return true;
+
+    needs_closing = false;
+    if (!fp) {
+	if (!(fp = Iopen(workname, FOPEN_R_WORK, (struct stat*)0))) {
+	    eerror(workname);
+	    return false;
+	}
+	needs_closing = true;
+    }
+
+    /* initialize to empty */
+    bufscpy(&prevauthor, "");
+    bufscpy(&prevdate, "");
+    bufscpy(&prevname, "");  prevname_found = 0;
+    bufscpy(&prevrev, "");
+    bufscpy(&prevstate, "");
+
+    c = '\0'; /* anything but KDELIM */
+    for (;;) {
+        if ( c==KDELIM) {
+	    do {
+		/* try to get keyword */
+		tp = keyword;
+		for (;;) {
+		    Igeteof_(fp, c, goto ok;)
+		    switch (c) {
+			default:
+			    if (keyword+keylength <= tp)
+				break;
+			    *tp++ = c;
+			    continue;
+
+			case '\n': case KDELIM: case VDELIM:
+			    break;
+		    }
+		    break;
+		}
+	    } while (c==KDELIM);
+            if (c!=VDELIM) continue;
+	    *tp = c;
+	    Igeteof_(fp, c, break;)
+	    switch (c) {
+		case ' ': case '\t': break;
+		default: continue;
+	    }
+
+	    switch (trymatch(keyword)) {
+            case Author:
+		if (!keepid(0, fp, &prevauthor))
+		    return false;
+		c = 0;
+                break;
+            case Date:
+		if (!(c = keepdate(fp)))
+		    return false;
+                break;
+            case Header:
+            case Id:
+	    case LocalId:
+		if (!(
+		      getval(fp, (struct buf*)0, false) &&
+		      keeprev(fp) &&
+		      (c = keepdate(fp)) &&
+		      keepid(c, fp, &prevauthor) &&
+		      keepid(0, fp, &prevstate)
+		))
+		    return false;
+		/* Skip either ``who'' (new form) or ``Locker: who'' (old).  */
+		if (getval(fp, (struct buf*)0, true) &&
+		    getval(fp, (struct buf*)0, true))
+			c = 0;
+		else if (nerror)
+			return false;
+		else
+			c = KDELIM;
+		break;
+            case Locker:
+		(void) getval(fp, (struct buf*)0, false);
+		c = 0;
+		break;
+            case Log:
+            case RCSfile:
+            case Source:
+		if (!getval(fp, (struct buf*)0, false))
+		    return false;
+		c = 0;
+                break;
+	    case Name:
+		if (getval(fp, &prevname, false)) {
+		    if (*prevname.string)
+			checkssym(prevname.string);
+		    prevname_found = 1;
+		}
+		c = 0;
+		break;
+            case Revision:
+		if (!keeprev(fp))
+		    return false;
+		c = 0;
+                break;
+            case State:
+		if (!keepid(0, fp, &prevstate))
+		    return false;
+		c = 0;
+                break;
+            default:
+               continue;
+            }
+	    if (!c)
+		Igeteof_(fp, c, c=0;)
+	    if (c != KDELIM) {
+		workerror("closing %c missing on keyword", KDELIM);
+		return false;
+	    }
+	    if (prevname_found &&
+		*prevauthor.string && *prevdate.string &&
+		*prevrev.string && *prevstate.string
+	    )
+                break;
+        }
+	Igeteof_(fp, c, break;)
+    }
+
+ ok:
+    if (needs_closing)
+	Ifclose(fp);
+    else
+	Irewind(fp);
+    prevkeys = true;
+    return true;
+}
+
+	static int
+badly_terminated()
+{
+	workerror("badly terminated keyword value");
+	return false;
+}
+
+	static int
+getval(fp, target, optional)
+	register RILE *fp;
+	struct buf *target;
+	int optional;
+/* Reads a keyword value from FP into TARGET.
+ * Returns true if one is found, false otherwise.
+ * Does not modify target if it is 0.
+ * Do not report an error if OPTIONAL is set and KDELIM is found instead.
+ */
+{
+	int c;
+	Igeteof_(fp, c, return badly_terminated();)
+	return get0val(c, fp, target, optional);
+}
+
+	static int
+get0val(c, fp, target, optional)
+	register int c;
+	register RILE *fp;
+	struct buf *target;
+	int optional;
+/* Reads a keyword value from C+FP into TARGET, perhaps OPTIONALly.
+ * Same as getval, except C is the lookahead character.
+ */
+{   register char * tp;
+    char const *tlim;
+    register int got1;
+
+    if (target) {
+	bufalloc(target, 1);
+	tp = target->string;
+	tlim = tp + target->size;
+    } else
+	tlim = tp = 0;
+    got1 = false;
+    for (;;) {
+	switch (c) {
+	    default:
+		got1 = true;
+		if (tp) {
+		    *tp++ = c;
+		    if (tlim <= tp)
+			tp = bufenlarge(target, &tlim);
+		}
+		break;
+
+	    case ' ':
+	    case '\t':
+		if (tp) {
+		    *tp = 0;
+#		    ifdef KEEPTEST
+			VOID printf("getval: %s\n", target);
+#		    endif
+		}
+		return got1;
+
+	    case KDELIM:
+		if (!got1 && optional)
+		    return false;
+		/* fall into */
+	    case '\n':
+	    case 0:
+		return badly_terminated();
+	}
+	Igeteof_(fp, c, return badly_terminated();)
+    }
+}
+
+
+	static int
+keepdate(fp)
+	RILE *fp;
+/* Function: reads a date prevdate; checks format
+ * Return 0 on error, lookahead character otherwise.
+ */
+{
+    struct buf prevday, prevtime;
+    register int c;
+
+    c = 0;
+    bufautobegin(&prevday);
+    if (getval(fp,&prevday,false)) {
+	bufautobegin(&prevtime);
+	if (getval(fp,&prevtime,false)) {
+	    Igeteof_(fp, c, c=0;)
+	    if (c) {
+		register char const *d = prevday.string, *t = prevtime.string;
+		bufalloc(&prevdate, strlen(d) + strlen(t) + 9);
+		VOID sprintf(prevdate.string, "%s%s %s%s",
+		    /* Parse dates put out by old versions of RCS.  */
+		      isdigit(d[0]) && isdigit(d[1]) && !isdigit(d[2])
+		    ? "19" : "",
+		    d, t,
+		    strchr(t,'-') || strchr(t,'+')  ?  ""  :  "+0000"
+		);
+	    }
+	}
+	bufautoend(&prevtime);
+    }
+    bufautoend(&prevday);
+    return c;
+}
+
+	static int
+keepid(c, fp, b)
+	int c;
+	RILE *fp;
+	struct buf *b;
+/* Get previous identifier from C+FP into B.  */
+{
+	if (!c)
+	    Igeteof_(fp, c, return false;)
+	if (!get0val(c, fp, b, false))
+	    return false;
+	checksid(b->string);
+	return !nerror;
+}
+
+	static int
+keeprev(fp)
+	RILE *fp;
+/* Get previous revision from FP into prevrev.  */
+{
+	return getval(fp,&prevrev,false) && checknum(prevrev.string);
+}
+
+
+	static int
+checknum(s)
+	char const *s;
+{
+    register char const *sp;
+    register int dotcount = 0;
+    for (sp=s; ; sp++) {
+	switch (*sp) {
+	    case 0:
+		if (dotcount & 1)
+		    return true;
+		else
+		    break;
+
+	    case '.':
+		dotcount++;
+		continue;
+
+	    default:
+		if (isdigit(*sp))
+		    continue;
+		break;
+	}
+	break;
+    }
+    workerror("%s is not a revision number", s);
+    return false;
+}
+
+
+
+#ifdef KEEPTEST
+
+/* Print the keyword values found.  */
+
+char const cmdid[] ="keeptest";
+
+	int
+main(argc, argv)
+int  argc; char  *argv[];
+{
+        while (*(++argv)) {
+		workname = *argv;
+		getoldkeys((RILE*)0);
+                VOID printf("%s:  revision: %s, date: %s, author: %s, name: %s, state: %s\n",
+			    *argv, prevrev.string, prevdate.string, prevauthor.string, prevname.string, prevstate.string);
+	}
+	exitmain(EXIT_SUCCESS);
+}
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcskeys.c b/gnu/usr.bin/rcs/lib/rcskeys.c
new file mode 100644
index 0000000000000..378f57dd0f775
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcskeys.c
@@ -0,0 +1,186 @@
+/* RCS keyword table and match operation */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.4  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.3  1993/11/03 17:42:27  eggert
+ * Add Name keyword.
+ *
+ * Revision 5.2  1991/08/19  03:13:55  eggert
+ * Say `T const' instead of `const T'; it's less confusing for pointer types.
+ * (This change was made in other source files too.)
+ *
+ * Revision 5.1  1991/04/21  11:58:25  eggert
+ * Don't put , just before } in initializer.
+ *
+ * Revision 5.0  1990/08/22  08:12:54  eggert
+ * Add -k.  Ansify and Posixate.
+ *
+ * Revision 4.3  89/05/01  15:13:02  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.2  87/10/18  10:36:33  narten
+ * Updating version numbers. Changes relative to 1.1 actuallyt
+ * relative to 4.1
+ *
+ * Revision 1.2  87/09/24  14:00:10  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 4.1  83/05/04  10:06:53  wft
+ * Initial revision.
+ *
+ */
+
+
+#include "rcsbase.h"
+
+libId(keysId, "$FreeBSD$")
+
+
+char const *Keyword[] = {
+    /* This must be in the same order as rcsbase.h's enum markers type. */
+	0,
+	AUTHOR, DATE, HEADER, IDH,
+	LOCKER, LOG, NAME, RCSFILE, REVISION, SOURCE, STATE, CVSHEADER,
+	NULL
+};
+
+/* Expand all keywords by default */
+static int ExpandKeyword[] = {
+	false,
+	true, true, true, true,
+	true, true, true, true, true, true, true, true,
+	true
+};
+enum markers LocalIdMode = Id;
+
+	enum markers
+trymatch(string)
+	char const *string;
+/* function: Checks whether string starts with a keyword followed
+ * by a KDELIM or a VDELIM.
+ * If successful, returns the appropriate marker, otherwise Nomatch.
+ */
+{
+        register int j;
+	register char const *p, *s;
+	for (j = sizeof(Keyword)/sizeof(*Keyword);  (--j);  ) {
+		if (!ExpandKeyword[j])
+			continue;
+		/* try next keyword */
+		p = Keyword[j];
+		if (p == NULL)
+			continue;
+		s = string;
+		while (*p++ == *s++) {
+			if (!*p)
+			    switch (*s) {
+				case KDELIM:
+				case VDELIM:
+				    return (enum markers)j;
+				default:
+				    return Nomatch;
+			    }
+		}
+        }
+        return(Nomatch);
+}
+
+	void
+setIncExc(arg)
+	char const *arg;
+/* Sets up the ExpandKeyword table according to command-line flags */
+{
+	char *key;
+	char *copy, *next;
+	int include = 0, j;
+
+	copy = strdup(arg);
+	next = copy;
+	switch (*next++) {
+	    case 'e':
+		include = false;
+		break;
+	    case 'i':
+		include = true;
+		break;
+	    default:
+		free(copy);
+		return;
+	}
+	if (include)
+		for (j = sizeof(Keyword)/sizeof(*Keyword);  (--j);  )
+			ExpandKeyword[j] = false;
+	key = strtok(next, ",");
+	while (key) {
+		for (j = sizeof(Keyword)/sizeof(*Keyword);  (--j);  ) {
+			if (Keyword[j] == NULL)
+				continue;
+			if (!strcmp(key, Keyword[j]))
+				ExpandKeyword[j] = include;
+		}
+		key = strtok(NULL, ",");
+	}
+	free(copy);
+	return;
+}
+
+	void
+setRCSLocalId(string)
+	char const *string;
+/* function: sets local RCS id and RCSLOCALID envariable */
+{
+	static char local_id[keylength+1];
+	char *copy, *next, *key;
+	int j;
+
+	copy = strdup(string);
+	next = copy;
+	key = strtok(next, "=");
+	if (strlen(key) > keylength)
+		faterror("LocalId is too long");
+	VOID strcpy(local_id, key);
+	Keyword[LocalId] = local_id;
+
+	/* options? */
+	while (key = strtok(NULL, ",")) {
+		if (!strcmp(key, Keyword[Id]))
+			LocalIdMode=Id;
+		else if (!strcmp(key, Keyword[Header]))
+			LocalIdMode=Header;
+		else if (!strcmp(key, Keyword[CVSHeader]))
+			LocalIdMode=CVSHeader;
+		else
+			error("Unknown LocalId mode");
+	}
+	free(copy);
+}
diff --git a/gnu/usr.bin/rcs/lib/rcslex.c b/gnu/usr.bin/rcs/lib/rcslex.c
new file mode 100644
index 0000000000000..7a11f79b46c86
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcslex.c
@@ -0,0 +1,1568 @@
+/* lexical analysis of RCS files */
+
+/******************************************************************************
+ *                     Lexical Analysis.
+ *                     hashtable, Lexinit, nextlex, getlex, getkey,
+ *                     getid, getnum, readstring, printstring, savestring,
+ *                     checkid, fatserror, error, faterror, warn, diagnose
+ *                     Testprogram: define LEXDB
+ ******************************************************************************
+ */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+
+
+/*
+ * Revision 5.19  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.18  1995/06/01 16:23:43  eggert
+ * (map_fd_deallocate,mmap_deallocate,read_deallocate,nothing_to_deallocate):
+ * New functions.
+ * (Iclose): If large_memory and maps_memory, use them to deallocate mapping.
+ * (fd2RILE): Use map_fd if available.
+ * If one mapping method fails, try the next instead of giving up;
+ * if they all fail, fall back on ordinary read.
+ * Work around bug: root mmap over NFS succeeds, but accessing dumps core.
+ * Use MAP_FAILED macro for mmap failure, and `char *' instead of caddr_t.
+ * (advise_access): Use madvise only if this instance used mmap.
+ * (Iopen): Use fdSafer to get safer file descriptor.
+ * (aflush): Moved here from rcsedit.c.
+ *
+ * Revision 5.17  1994/03/20 04:52:58  eggert
+ * Don't worry if madvise fails.  Add Orewind.  Remove lint.
+ *
+ * Revision 5.16  1993/11/09 17:55:29  eggert
+ * Fix `label: }' typo.
+ *
+ * Revision 5.15  1993/11/03 17:42:27  eggert
+ * Improve quality of diagnostics by putting file names in them more often.
+ * Don't discard ignored phrases.
+ *
+ * Revision 5.14  1992/07/28  16:12:44  eggert
+ * Identifiers may now start with a digit and (unless they are symbolic names)
+ * may contain `.'.  Avoid `unsigned'.  Statement macro names now end in _.
+ *
+ * Revision 5.13  1992/02/17  23:02:27  eggert
+ * Work around NFS mmap SIGBUS problem.
+ *
+ * Revision 5.12  1992/01/06  02:42:34  eggert
+ * Use OPEN_O_BINARY if mode contains 'b'.
+ *
+ * Revision 5.11  1991/11/03  03:30:44  eggert
+ * Fix porting bug to ancient hosts lacking vfprintf.
+ *
+ * Revision 5.10  1991/10/07  17:32:46  eggert
+ * Support piece tables even if !has_mmap.
+ *
+ * Revision 5.9  1991/09/24  00:28:42  eggert
+ * Don't export errsay().
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Add eoflex(), mmap support.  Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:26  eggert
+ * Add MS-DOS support.
+ *
+ * Revision 5.6  1991/02/25  07:12:42  eggert
+ * Work around fputs bug.  strsave -> str_save (DG/UX name clash)
+ *
+ * Revision 5.5  1990/12/04  05:18:47  eggert
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.4  1990/11/19  20:05:28  hammer
+ * no longer gives warning about unknown keywords if -q is specified
+ *
+ * Revision 5.3  1990/11/01  05:03:48  eggert
+ * When ignoring unknown phrases, copy them to the output RCS file.
+ *
+ * Revision 5.2  1990/09/04  08:02:27  eggert
+ * Count RCS lines better.
+ *
+ * Revision 5.1  1990/08/29  07:14:03  eggert
+ * Work around buggy compilers with defective argument promotion.
+ *
+ * Revision 5.0  1990/08/22  08:12:55  eggert
+ * Remove compile-time limits; use malloc instead.
+ * Report errno-related errors with perror().
+ * Ansify and Posixate.  Add support for ISO 8859.
+ * Use better hash function.
+ *
+ * Revision 4.6  89/05/01  15:13:07  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.5  88/08/28  15:01:12  eggert
+ * Don't loop when writing error messages to a full filesystem.
+ * Flush stderr/stdout when mixing output.
+ * Yield exit status compatible with diff(1).
+ * Shrink stdio code size; allow cc -R; remove lint.
+ *
+ * Revision 4.4  87/12/18  11:44:47  narten
+ * fixed to use "varargs" in "fprintf"; this is required if it is to
+ * work on a SPARC machine such as a Sun-4
+ *
+ * Revision 4.3  87/10/18  10:37:18  narten
+ * Updating version numbers. Changes relative to 1.1 actually relative
+ * to version 4.1
+ *
+ * Revision 1.3  87/09/24  14:00:17  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:33  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/03/25  18:12:51  wft
+ * Only changed $Header to $Id.
+ *
+ * Revision 3.3  82/12/10  16:22:37  wft
+ * Improved error messages, changed exit status on error to 1.
+ *
+ * Revision 3.2  82/11/28  21:27:10  wft
+ * Renamed ctab to map and included EOFILE; ctab is now a macro in rcsbase.h.
+ * Added fflsbuf(), fputs(), and fprintf(), which abort the RCS operations
+ * properly in case there is an IO-error (e.g., file system full).
+ *
+ * Revision 3.1  82/10/11  19:43:56  wft
+ * removed unused label out:;
+ * made sure all calls to getc() return into an integer, not a char.
+ */
+
+
+/*
+#define LEXDB
+*/
+/* version LEXDB is for testing the lexical analyzer. The testprogram
+ * reads a stream of lexemes, enters the revision numbers into the
+ * hashtable, and prints the recognized tokens. Keywords are recognized
+ * as identifiers.
+ */
+
+
+
+#include "rcsbase.h"
+
+libId(lexId, "$FreeBSD$")
+
+static char *checkidentifier P((char*,int,int));
+static void errsay P((char const*));
+static void fatsay P((char const*));
+static void lookup P((char const*));
+static void startsay P((const char*,const char*));
+static void warnsay P((char const*));
+
+static struct hshentry *nexthsh;  /*pointer to next hash entry, set by lookup*/
+
+enum tokens     nexttok;    /*next token, set by nextlex                    */
+
+int             hshenter;   /*if true, next suitable lexeme will be entered */
+                            /*into the symbol table. Handle with care.      */
+int             nextc;      /*next input character, initialized by Lexinit  */
+
+long		rcsline;    /*current line-number of input		    */
+int             nerror;     /*counter for errors                            */
+int             quietflag;  /*indicates quiet mode                          */
+RILE *		finptr;	    /*input file descriptor			    */
+
+FILE *          frewrite;   /*file descriptor for echoing input             */
+
+FILE *		foutptr;    /* copy of frewrite, but 0 to suppress echo  */
+
+static struct buf tokbuf;   /* token buffer				    */
+
+char const *    NextString; /* next token				    */
+
+/*
+ * Our hash algorithm is h[0] = 0, h[i+1] = 4*h[i] + c,
+ * so hshsize should be odd.
+ * See B J McKenzie, R Harries & T Bell, Selecting a hashing algorithm,
+ * Software--practice & experience 20, 2 (Feb 1990), 209-224.
+ */
+#ifndef hshsize
+#	define hshsize 511
+#endif
+
+static struct hshentry *hshtab[hshsize]; /*hashtable			    */
+
+static int ignored_phrases; /* have we ignored phrases in this RCS file? */
+
+    void
+warnignore()
+{
+    if (!ignored_phrases) {
+	ignored_phrases = true;
+	rcswarn("Unknown phrases like `%s ...;' are present.", NextString);
+    }
+}
+
+
+
+	static void
+lookup(str)
+	char const *str;
+/* Function: Looks up the character string pointed to by str in the
+ * hashtable. If the string is not present, a new entry for it is created.
+ * In any case, the address of the corresponding hashtable entry is placed
+ * into nexthsh.
+ */
+{
+	register unsigned ihash;  /* index into hashtable */
+	register char const *sp;
+	register struct hshentry *n, **p;
+
+        /* calculate hash code */
+	sp = str;
+        ihash = 0;
+	while (*sp)
+		ihash  =  (ihash<<2) + *sp++;
+	ihash %= hshsize;
+
+	for (p = &hshtab[ihash];  ;  p = &n->nexthsh)
+		if (!(n = *p)) {
+			/* empty slot found */
+			*p = n = ftalloc(struct hshentry);
+			n->num = fstr_save(str);
+			n->nexthsh = 0;
+#			ifdef LEXDB
+				VOID printf("\nEntered: %s at %u ", str, ihash);
+#			endif
+			break;
+		} else if (strcmp(str, n->num) == 0)
+			/* match found */
+			break;
+	nexthsh = n;
+	NextString = n->num;
+}
+
+
+
+
+
+
+	void
+Lexinit()
+/* Function: Initialization of lexical analyzer:
+ * initializes the hashtable,
+ * initializes nextc, nexttok if finptr != 0
+ */
+{       register int            c;
+
+	for (c = hshsize;  0 <= --c;  ) {
+		hshtab[c] = 0;
+        }
+
+	nerror = 0;
+	if (finptr) {
+		foutptr = 0;
+		hshenter = true;
+		ignored_phrases = false;
+		rcsline = 1;
+		bufrealloc(&tokbuf, 2);
+		Iget_(finptr, nextc)
+                nextlex();            /*initial token*/
+        }
+}
+
+
+
+
+
+
+
+	void
+nextlex()
+
+/* Function: Reads the next token and sets nexttok to the next token code.
+ * Only if hshenter is set, a revision number is entered into the
+ * hashtable and a pointer to it is placed into nexthsh.
+ * This is useful for avoiding that dates are placed into the hashtable.
+ * For ID's and NUM's, NextString is set to the character string.
+ * Assumption: nextc contains the next character.
+ */
+{       register c;
+	declarecache;
+	register FILE *frew;
+        register char * sp;
+	char const *limit;
+        register enum tokens d;
+	register RILE *fin;
+
+	fin=finptr; frew=foutptr;
+	setupcache(fin); cache(fin);
+	c = nextc;
+
+	for (;;) { switch ((d = ctab[c])) {
+
+	default:
+		fatserror("unknown character `%c'", c);
+		/*NOTREACHED*/
+
+        case NEWLN:
+		++rcsline;
+#               ifdef LEXDB
+		afputc('\n',stdout);
+#               endif
+                /* Note: falls into next case */
+
+        case SPACE:
+		GETC_(frew, c)
+		continue;
+
+	case IDCHAR:
+	case LETTER:
+	case Letter:
+		d = ID;
+		/* fall into */
+	case DIGIT:
+	case PERIOD:
+		sp = tokbuf.string;
+		limit = sp + tokbuf.size;
+		*sp++ = c;
+		for (;;) {
+			GETC_(frew, c)
+			switch (ctab[c]) {
+			    case IDCHAR:
+			    case LETTER:
+			    case Letter:
+				d = ID;
+				/* fall into */
+			    case DIGIT:
+			    case PERIOD:
+				*sp++ = c;
+				if (limit <= sp)
+					sp = bufenlarge(&tokbuf, &limit);
+				continue;
+
+			    default:
+				break;
+			}
+			break;
+                }
+		*sp = 0;
+		if (d == DIGIT  ||  d == PERIOD) {
+			d = NUM;
+			if (hshenter) {
+				lookup(tokbuf.string);
+				break;
+			}
+		}
+		NextString = fstr_save(tokbuf.string);
+		break;
+
+        case SBEGIN: /* long string */
+		d = STRING;
+                /* note: only the initial SBEGIN has been read*/
+                /* read the string, and reset nextc afterwards*/
+		break;
+
+	case COLON:
+	case SEMI:
+		GETC_(frew, c)
+		break;
+	} break; }
+	nextc = c;
+	nexttok = d;
+	uncache(fin);
+}
+
+	int
+eoflex()
+/*
+ * Yield true if we look ahead to the end of the input, false otherwise.
+ * nextc becomes undefined at end of file.
+ */
+{
+	register int c;
+	declarecache;
+	register FILE *fout;
+	register RILE *fin;
+
+	c = nextc;
+	fin = finptr;
+	fout = foutptr;
+	setupcache(fin); cache(fin);
+
+	for (;;) {
+		switch (ctab[c]) {
+			default:
+				nextc = c;
+				uncache(fin);
+				return false;
+
+			case NEWLN:
+				++rcsline;
+				/* fall into */
+			case SPACE:
+				cachegeteof_(c, {uncache(fin);return true;})
+				break;
+		}
+		if (fout)
+			aputc_(c, fout)
+	}
+}
+
+
+int getlex(token)
+enum tokens token;
+/* Function: Checks if nexttok is the same as token. If so,
+ * advances the input by calling nextlex and returns true.
+ * otherwise returns false.
+ * Doesn't work for strings and keywords; loses the character string for ids.
+ */
+{
+        if (nexttok==token) {
+                nextlex();
+                return(true);
+        } else  return(false);
+}
+
+	int
+getkeyopt(key)
+	char const *key;
+/* Function: If the current token is a keyword identical to key,
+ * advances the input by calling nextlex and returns true;
+ * otherwise returns false.
+ */
+{
+	if (nexttok==ID  &&  strcmp(key,NextString) == 0) {
+		 /* match found */
+		 ffree1(NextString);
+		 nextlex();
+		 return(true);
+        }
+        return(false);
+}
+
+	void
+getkey(key)
+	char const *key;
+/* Check that the current input token is a keyword identical to key,
+ * and advance the input by calling nextlex.
+ */
+{
+	if (!getkeyopt(key))
+		fatserror("missing '%s' keyword", key);
+}
+
+	void
+getkeystring(key)
+	char const *key;
+/* Check that the current input token is a keyword identical to key,
+ * and advance the input by calling nextlex; then look ahead for a string.
+ */
+{
+	getkey(key);
+	if (nexttok != STRING)
+		fatserror("missing string after '%s' keyword", key);
+}
+
+
+	char const *
+getid()
+/* Function: Checks if nexttok is an identifier. If so,
+ * advances the input by calling nextlex and returns a pointer
+ * to the identifier; otherwise returns 0.
+ * Treats keywords as identifiers.
+ */
+{
+	register char const *name;
+        if (nexttok==ID) {
+                name = NextString;
+                nextlex();
+                return name;
+	} else
+		return 0;
+}
+
+
+struct hshentry * getnum()
+/* Function: Checks if nexttok is a number. If so,
+ * advances the input by calling nextlex and returns a pointer
+ * to the hashtable entry.  Otherwise returns 0.
+ * Doesn't work if hshenter is false.
+ */
+{
+        register struct hshentry * num;
+        if (nexttok==NUM) {
+                num=nexthsh;
+                nextlex();
+                return num;
+	} else
+		return 0;
+}
+
+	struct cbuf
+getphrases(key)
+	char const *key;
+/*
+* Get a series of phrases that do not start with KEY.  Yield resulting buffer.
+* Stop when the next phrase starts with a token that is not an identifier,
+* or is KEY.  Copy input to foutptr if it is set.  Unlike ignorephrases(),
+* this routine assumes nextlex() has already been invoked before we start.
+*/
+{
+    declarecache;
+    register int c;
+    register char const *kn;
+    struct cbuf r;
+    register RILE *fin;
+    register FILE *frew;
+#   if large_memory
+#	define savech_(c) ;
+#   else
+	register char *p;
+	char const *limit;
+	struct buf b;
+#	define savech_(c) {if (limit<=p)p=bufenlarge(&b,&limit); *p++ =(c);}
+#   endif
+
+    if (nexttok!=ID  ||  strcmp(NextString,key) == 0)
+	clear_buf(&r);
+    else {
+	warnignore();
+	fin = finptr;
+	frew = foutptr;
+	setupcache(fin); cache(fin);
+#	if large_memory
+	    r.string = (char const*)cacheptr() - strlen(NextString) - 1;
+#	else
+	    bufautobegin(&b);
+	    bufscpy(&b, NextString);
+	    p = b.string + strlen(b.string);
+	    limit = b.string + b.size;
+#	endif
+	ffree1(NextString);
+	c = nextc;
+	for (;;) {
+	    for (;;) {
+		savech_(c)
+		switch (ctab[c]) {
+		    default:
+			fatserror("unknown character `%c'", c);
+			/*NOTREACHED*/
+		    case NEWLN:
+			++rcsline;
+			/* fall into */
+		    case COLON: case DIGIT: case LETTER: case Letter:
+		    case PERIOD: case SPACE:
+			GETC_(frew, c)
+			continue;
+		    case SBEGIN: /* long string */
+			for (;;) {
+			    for (;;) {
+				GETC_(frew, c)
+				savech_(c)
+				switch (c) {
+				    case '\n':
+					++rcsline;
+					/* fall into */
+				    default:
+					continue;
+
+				    case SDELIM:
+					break;
+				}
+				break;
+			    }
+			    GETC_(frew, c)
+			    if (c != SDELIM)
+				break;
+			    savech_(c)
+			}
+			continue;
+		    case SEMI:
+			cacheget_(c)
+			if (ctab[c] == NEWLN) {
+			    if (frew)
+				aputc_(c, frew)
+			    ++rcsline;
+			    savech_(c)
+			    cacheget_(c)
+			}
+#			if large_memory
+			    r.size = (char const*)cacheptr() - 1 - r.string;
+#			endif
+			for (;;) {
+			    switch (ctab[c]) {
+				case NEWLN:
+					++rcsline;
+					/* fall into */
+				case SPACE:
+					cacheget_(c)
+					continue;
+
+				default: break;
+			    }
+			    break;
+			}
+			if (frew)
+			    aputc_(c, frew)
+			break;
+		}
+		break;
+	    }
+	    if (ctab[c] == Letter) {
+		    for (kn = key;  c && *kn==c;  kn++)
+			GETC_(frew, c)
+		    if (!*kn)
+			switch (ctab[c]) {
+			    case DIGIT: case LETTER: case Letter:
+			    case IDCHAR: case PERIOD:
+				break;
+			    default:
+				nextc = c;
+				NextString = fstr_save(key);
+				nexttok = ID;
+				uncache(fin);
+				goto returnit;
+			}
+#		    if !large_memory
+			{
+			    register char const *ki;
+			    for (ki=key; ki<kn; )
+				savech_(*ki++)
+			}
+#		    endif
+	    } else {
+		    nextc = c;
+		    uncache(fin);
+		    nextlex();
+		    break;
+	    }
+	}
+    returnit:;
+#	if !large_memory
+	    return bufremember(&b, (size_t)(p - b.string));
+#	endif
+    }
+    return r;
+}
+
+
+	void
+readstring()
+/* skip over characters until terminating single SDELIM        */
+/* If foutptr is set, copy every character read to foutptr.    */
+/* Does not advance nextlex at the end.                        */
+{       register c;
+	declarecache;
+	register FILE *frew;
+	register RILE *fin;
+	fin=finptr; frew=foutptr;
+	setupcache(fin); cache(fin);
+	for (;;) {
+		GETC_(frew, c)
+		switch (c) {
+		    case '\n':
+			++rcsline;
+			break;
+
+		    case SDELIM:
+			GETC_(frew, c)
+			if (c != SDELIM) {
+				/* end of string */
+				nextc = c;
+				uncache(fin);
+				return;
+			}
+			break;
+		}
+	}
+}
+
+
+	void
+printstring()
+/* Function: copy a string to stdout, until terminated with a single SDELIM.
+ * Does not advance nextlex at the end.
+ */
+{
+        register c;
+	declarecache;
+	register FILE *fout;
+	register RILE *fin;
+	fin=finptr;
+	fout = stdout;
+	setupcache(fin); cache(fin);
+	for (;;) {
+		cacheget_(c)
+		switch (c) {
+		    case '\n':
+			++rcsline;
+			break;
+		    case SDELIM:
+			cacheget_(c)
+			if (c != SDELIM) {
+                                nextc=c;
+				uncache(fin);
+                                return;
+                        }
+			break;
+                }
+		aputc_(c,fout)
+        }
+}
+
+
+
+	struct cbuf
+savestring(target)
+	struct buf *target;
+/* Copies a string terminated with SDELIM from file finptr to buffer target.
+ * Double SDELIM is replaced with SDELIM.
+ * If foutptr is set, the string is also copied unchanged to foutptr.
+ * Does not advance nextlex at the end.
+ * Yield a copy of *TARGET, except with exact length.
+ */
+{
+        register c;
+	declarecache;
+	register FILE *frew;
+	register char *tp;
+	register RILE *fin;
+	char const *limit;
+	struct cbuf r;
+
+	fin=finptr; frew=foutptr;
+	setupcache(fin); cache(fin);
+	tp = target->string;  limit = tp + target->size;
+	for (;;) {
+		GETC_(frew, c)
+		switch (c) {
+		    case '\n':
+			++rcsline;
+			break;
+		    case SDELIM:
+			GETC_(frew, c)
+			if (c != SDELIM) {
+                                /* end of string */
+                                nextc=c;
+				r.string = target->string;
+				r.size = tp - r.string;
+				uncache(fin);
+				return r;
+                        }
+			break;
+                }
+		if (tp == limit)
+			tp = bufenlarge(target, &limit);
+		*tp++ = c;
+        }
+}
+
+
+	static char *
+checkidentifier(id, delimiter, dotok)
+	register char *id;
+	int delimiter;
+	register int dotok;
+/*   Function:  check whether the string starting at id is an   */
+/*		identifier and return a pointer to the delimiter*/
+/*		after the identifier.  White space, delim and 0 */
+/*              are legal delimiters.  Aborts the program if not*/
+/*              a legal identifier. Useful for checking commands*/
+/*		If !delim, the only delimiter is 0.		*/
+/*		Allow '.' in identifier only if DOTOK is set.   */
+{
+        register char    *temp;
+	register char c;
+	register char delim = delimiter;
+	int isid = false;
+
+	temp = id;
+	for (;;  id++) {
+		switch (ctab[(unsigned char)(c = *id)]) {
+			case IDCHAR:
+			case LETTER:
+			case Letter:
+				isid = true;
+				continue;
+
+			case DIGIT:
+				continue;
+
+			case PERIOD:
+				if (dotok)
+					continue;
+				break;
+
+			default:
+				break;
+		}
+		break;
+	}
+	if (	 ! isid
+	    ||	 (c  &&  (!delim || (c!=delim && c!=' ' && c!='\t' && c!='\n')))
+	) {
+                /* append \0 to end of id before error message */
+		while ((c = *id) && c!=' ' && c!='\t' && c!='\n' && c!=delim)
+		    id++;
+                *id = '\0';
+		faterror("invalid %s `%s'",
+			dotok ? "identifier" : "symbol", temp
+		);
+	}
+	return id;
+}
+
+	char *
+checkid(id, delimiter)
+	char *id;
+	int delimiter;
+{
+	return checkidentifier(id, delimiter, true);
+}
+
+	char *
+checksym(sym, delimiter)
+	char *sym;
+	int delimiter;
+{
+	return checkidentifier(sym, delimiter, false);
+}
+
+	void
+checksid(id)
+	char *id;
+/* Check whether the string ID is an identifier.  */
+{
+	VOID checkid(id, 0);
+}
+
+	void
+checkssym(sym)
+	char *sym;
+{
+	VOID checksym(sym, 0);
+}
+
+
+#if !large_memory
+#   define Iclose(f) fclose(f)
+#else
+# if !maps_memory
+    static int Iclose P((RILE *));
+	static int
+    Iclose(f)
+	register RILE *f;
+    {
+	tfree(f->base);
+	f->base = 0;
+	return fclose(f->stream);
+    }
+# else
+    static int Iclose P((RILE *));
+	static int
+    Iclose(f)
+	register RILE *f;
+    {
+	(* f->deallocate) (f);
+	f->base = 0;
+	return close(f->fd);
+    }
+
+#   if has_map_fd
+	static void map_fd_deallocate P((RILE *));
+	    static void
+	map_fd_deallocate(f)
+	    register RILE *f;
+	{
+	    if (vm_deallocate(
+		task_self(),
+		(vm_address_t) f->base,
+		(vm_size_t) (f->lim - f->base)
+	    ) != KERN_SUCCESS)
+		efaterror("vm_deallocate");
+	}
+#   endif
+#   if has_mmap
+	static void mmap_deallocate P((RILE *));
+	    static void
+	mmap_deallocate(f)
+	    register RILE *f;
+	{
+	    if (munmap((char *) f->base, (size_t) (f->lim - f->base)) != 0)
+		efaterror("munmap");
+	}
+#   endif
+    static void read_deallocate P((RILE *));
+	static void
+    read_deallocate(f)
+	RILE *f;
+    {
+	tfree(f->base);
+    }
+
+    static void nothing_to_deallocate P((RILE *));
+	static void
+    nothing_to_deallocate(f)
+	RILE *f;
+    {
+    }
+# endif
+#endif
+
+
+#if large_memory && maps_memory
+	static RILE *fd2_RILE P((int,char const*,struct stat*));
+	static RILE *
+fd2_RILE(fd, name, status)
+#else
+	static RILE *fd2RILE P((int,char const*,char const*,struct stat*));
+	static RILE *
+fd2RILE(fd, name, type, status)
+	char const *type;
+#endif
+	int fd;
+	char const *name;
+	register struct stat *status;
+{
+	struct stat st;
+
+	if (!status)
+		status = &st;
+	if (fstat(fd, status) != 0)
+		efaterror(name);
+	if (!S_ISREG(status->st_mode)) {
+		error("`%s' is not a regular file", name);
+		VOID close(fd);
+		errno = EINVAL;
+		return 0;
+	} else {
+
+#	    if !(large_memory && maps_memory)
+		FILE *stream;
+		if (!(stream = fdopen(fd, type)))
+			efaterror(name);
+#	    endif
+
+#	    if !large_memory
+		return stream;
+#	    else
+#		define RILES 3
+	      {
+		static RILE rilebuf[RILES];
+
+		register RILE *f;
+		size_t s = status->st_size;
+
+		if (s != status->st_size)
+			faterror("%s: too large", name);
+		for (f = rilebuf;  f->base;  f++)
+			if (f == rilebuf+RILES)
+				faterror("too many RILEs");
+#		if maps_memory
+			f->deallocate = nothing_to_deallocate;
+#		endif
+		if (!s) {
+		    static unsigned char nothing;
+		    f->base = &nothing; /* Any nonzero address will do.  */
+		} else {
+		    f->base = 0;
+#		    if has_map_fd
+			map_fd(
+				fd, (vm_offset_t)0, (vm_address_t*) &f->base,
+				TRUE, (vm_size_t)s
+			);
+			f->deallocate = map_fd_deallocate;
+#		    endif
+#		    if has_mmap
+			if (!f->base) {
+			    catchmmapints();
+			    f->base = (unsigned char *) mmap(
+				(char *)0, s, PROT_READ, MAP_SHARED,
+				fd, (off_t)0
+			    );
+#			    ifndef MAP_FAILED
+#			    define MAP_FAILED (-1)
+#			    endif
+			    if (f->base == (unsigned char *) MAP_FAILED)
+				f->base = 0;
+			    else {
+#				if has_NFS && mmap_signal
+				    /*
+				    * On many hosts, the superuser
+				    * can mmap an NFS file it can't read.
+				    * So access the first page now, and print
+				    * a nice message if a bus error occurs.
+				    */
+				    readAccessFilenameBuffer(name, f->base);
+#				endif
+			    }
+			    f->deallocate = mmap_deallocate;
+			}
+#		    endif
+		    if (!f->base) {
+			f->base = tnalloc(unsigned char, s);
+#			if maps_memory
+			{
+			    /*
+			    * We can't map the file into memory for some reason.
+			    * Read it into main memory all at once; this is
+			    * the simplest substitute for memory mapping.
+			    */
+			    char *bufptr = (char *) f->base;
+			    size_t bufsiz = s;
+			    do {
+				ssize_t r = read(fd, bufptr, bufsiz);
+				switch (r) {
+				    case -1:
+					efaterror(name);
+
+				    case 0:
+					/* The file must have shrunk!  */
+					status->st_size = s -= bufsiz;
+					bufsiz = 0;
+					break;
+
+				    default:
+					bufptr += r;
+					bufsiz -= r;
+					break;
+				}
+			    } while (bufsiz);
+			    if (lseek(fd, (off_t)0, SEEK_SET) == -1)
+				efaterror(name);
+			    f->deallocate = read_deallocate;
+			}
+#			endif
+		    }
+		}
+		f->ptr = f->base;
+		f->lim = f->base + s;
+		f->fd = fd;
+#		if !maps_memory
+		    f->readlim = f->base;
+		    f->stream = stream;
+#		endif
+		if_advise_access(s, f, MADV_SEQUENTIAL);
+		return f;
+	      }
+#	    endif
+	}
+}
+
+#if !maps_memory && large_memory
+	int
+Igetmore(f)
+	register RILE *f;
+{
+	register fread_type r;
+	register size_t s = f->lim - f->readlim;
+
+	if (BUFSIZ < s)
+		s = BUFSIZ;
+	if (!(r = Fread(f->readlim, sizeof(*f->readlim), s, f->stream))) {
+		testIerror(f->stream);
+		f->lim = f->readlim;  /* The file might have shrunk!  */
+		return 0;
+	}
+	f->readlim += r;
+	return 1;
+}
+#endif
+
+#if has_madvise && has_mmap && large_memory
+	void
+advise_access(f, advice)
+	register RILE *f;
+	int advice;
+{
+    if (f->deallocate == mmap_deallocate)
+	VOID madvise((char *)f->base, (size_t)(f->lim - f->base), advice);
+	/* Don't worry if madvise fails; it's only advisory.  */
+}
+#endif
+
+	RILE *
+#if large_memory && maps_memory
+I_open(name, status)
+#else
+Iopen(name, type, status)
+	char const *type;
+#endif
+	char const *name;
+	struct stat *status;
+/* Open NAME for reading, yield its descriptor, and set *STATUS.  */
+{
+	int fd = fdSafer(open(name, O_RDONLY
+#		if OPEN_O_BINARY
+			|  (strchr(type,'b') ? OPEN_O_BINARY : 0)
+#		endif
+	));
+
+	if (fd < 0)
+		return 0;
+#	if large_memory && maps_memory
+		return fd2_RILE(fd, name, status);
+#	else
+		return fd2RILE(fd, name, type, status);
+#	endif
+}
+
+
+static int Oerrloop;
+
+	void
+Oerror()
+{
+	if (Oerrloop)
+		exiterr();
+	Oerrloop = true;
+	efaterror("output error");
+}
+
+void Ieof() { fatserror("unexpected end of file"); }
+void Ierror() { efaterror("input error"); }
+void testIerror(f) FILE *f; { if (ferror(f)) Ierror(); }
+void testOerror(o) FILE *o; { if (ferror(o)) Oerror(); }
+
+void Ifclose(f) RILE *f; { if (f && Iclose(f)!=0) Ierror(); }
+void Ofclose(f) FILE *f; { if (f && fclose(f)!=0) Oerror(); }
+void Izclose(p) RILE **p; { Ifclose(*p); *p = 0; }
+void Ozclose(p) FILE **p; { Ofclose(*p); *p = 0; }
+
+#if !large_memory
+	void
+testIeof(f)
+	FILE *f;
+{
+	testIerror(f);
+	if (feof(f))
+		Ieof();
+}
+void Irewind(f) FILE *f; { if (fseek(f,0L,SEEK_SET) != 0) Ierror(); }
+#endif
+
+void Orewind(f) FILE *f; { if (fseek(f,0L,SEEK_SET) != 0) Oerror(); }
+
+void aflush(f) FILE *f; { if (fflush(f) != 0) Oerror(); }
+void eflush() { if (fflush(stderr)!=0 && !Oerrloop) Oerror(); }
+void oflush()
+{
+	if (fflush(workstdout ? workstdout : stdout) != 0  &&  !Oerrloop)
+		Oerror();
+}
+
+	void
+fatcleanup(already_newline)
+	int already_newline;
+{
+	VOID fprintf(stderr, already_newline+"\n%s aborted\n", cmdid);
+	exiterr();
+}
+
+	static void
+startsay(s, t)
+	const char *s, *t;
+{
+	oflush();
+	if (s)
+	    aprintf(stderr, "%s: %s: %s", cmdid, s, t);
+	else
+	    aprintf(stderr, "%s: %s", cmdid, t);
+}
+
+	static void
+fatsay(s)
+	char const *s;
+{
+	startsay(s, "");
+}
+
+	static void
+errsay(s)
+	char const *s;
+{
+	fatsay(s);
+	nerror++;
+}
+
+	static void
+warnsay(s)
+	char const *s;
+{
+	startsay(s, "warning: ");
+}
+
+void eerror(s) char const *s; { enerror(errno,s); }
+
+	void
+enerror(e,s)
+	int e;
+	char const *s;
+{
+	errsay((char const*)0);
+	errno = e;
+	perror(s);
+	eflush();
+}
+
+void efaterror(s) char const *s; { enfaterror(errno,s); }
+
+	void
+enfaterror(e,s)
+	int e;
+	char const *s;
+{
+	fatsay((char const*)0);
+	errno = e;
+	perror(s);
+	fatcleanup(true);
+}
+
+#if has_prototypes
+	void
+error(char const *format,...)
+#else
+	/*VARARGS1*/ void error(format, va_alist) char const *format; va_dcl
+#endif
+/* non-fatal error */
+{
+	va_list args;
+	errsay((char const*)0);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	afputc('\n',stderr);
+	eflush();
+}
+
+#if has_prototypes
+	void
+rcserror(char const *format,...)
+#else
+	/*VARARGS1*/ void rcserror(format, va_alist) char const *format; va_dcl
+#endif
+/* non-fatal RCS file error */
+{
+	va_list args;
+	errsay(RCSname);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	afputc('\n',stderr);
+	eflush();
+}
+
+#if has_prototypes
+	void
+workerror(char const *format,...)
+#else
+	/*VARARGS1*/ void workerror(format, va_alist) char const *format; va_dcl
+#endif
+/* non-fatal working file error */
+{
+	va_list args;
+	errsay(workname);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	afputc('\n',stderr);
+	eflush();
+}
+
+#if has_prototypes
+	void
+fatserror(char const *format,...)
+#else
+	/*VARARGS1*/ void
+	fatserror(format, va_alist) char const *format; va_dcl
+#endif
+/* fatal RCS file syntax error */
+{
+	va_list args;
+	oflush();
+	VOID fprintf(stderr, "%s: %s:%ld: ", cmdid, RCSname, rcsline);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	fatcleanup(false);
+}
+
+#if has_prototypes
+	void
+faterror(char const *format,...)
+#else
+	/*VARARGS1*/ void faterror(format, va_alist)
+	char const *format; va_dcl
+#endif
+/* fatal error, terminates program after cleanup */
+{
+	va_list args;
+	fatsay((char const*)0);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	fatcleanup(false);
+}
+
+#if has_prototypes
+	void
+rcsfaterror(char const *format,...)
+#else
+	/*VARARGS1*/ void rcsfaterror(format, va_alist)
+	char const *format; va_dcl
+#endif
+/* fatal RCS file error, terminates program after cleanup */
+{
+	va_list args;
+	fatsay(RCSname);
+	vararg_start(args, format);
+	fvfprintf(stderr, format, args);
+	va_end(args);
+	fatcleanup(false);
+}
+
+#if has_prototypes
+	void
+warn(char const *format,...)
+#else
+	/*VARARGS1*/ void warn(format, va_alist) char const *format; va_dcl
+#endif
+/* warning */
+{
+	va_list args;
+	if (!quietflag) {
+		warnsay((char *)0);
+		vararg_start(args, format);
+		fvfprintf(stderr, format, args);
+		va_end(args);
+		afputc('\n', stderr);
+		eflush();
+	}
+}
+
+#if has_prototypes
+	void
+rcswarn(char const *format,...)
+#else
+	/*VARARGS1*/ void rcswarn(format, va_alist) char const *format; va_dcl
+#endif
+/* RCS file warning */
+{
+	va_list args;
+	if (!quietflag) {
+		warnsay(RCSname);
+		vararg_start(args, format);
+		fvfprintf(stderr, format, args);
+		va_end(args);
+		afputc('\n', stderr);
+		eflush();
+	}
+}
+
+#if has_prototypes
+	void
+workwarn(char const *format,...)
+#else
+	/*VARARGS1*/ void workwarn(format, va_alist) char const *format; va_dcl
+#endif
+/* working file warning */
+{
+	va_list args;
+	if (!quietflag) {
+		warnsay(workname);
+		vararg_start(args, format);
+		fvfprintf(stderr, format, args);
+		va_end(args);
+		afputc('\n', stderr);
+		eflush();
+	}
+}
+
+	void
+redefined(c)
+	int c;
+{
+	warn("redefinition of -%c option", c);
+}
+
+#if has_prototypes
+	void
+diagnose(char const *format,...)
+#else
+	/*VARARGS1*/ void diagnose(format, va_alist) char const *format; va_dcl
+#endif
+/* prints a diagnostic message */
+/* Unlike the other routines, it does not append a newline. */
+/* This lets some callers suppress the newline, and is faster */
+/* in implementations that flush stderr just at the end of each printf. */
+{
+	va_list args;
+        if (!quietflag) {
+		oflush();
+		vararg_start(args, format);
+		fvfprintf(stderr, format, args);
+		va_end(args);
+		eflush();
+        }
+}
+
+
+
+	void
+afputc(c, f)
+/* afputc(c,f); acts like aputc_(c,f) but is smaller and slower.  */
+	int c;
+	register FILE *f;
+{
+	aputc_(c,f)
+}
+
+
+	void
+aputs(s, iop)
+	char const *s;
+	FILE *iop;
+/* Function: Put string s on file iop, abort on error.
+ */
+{
+#if has_fputs
+	if (fputs(s, iop) < 0)
+		Oerror();
+#else
+	awrite(s, strlen(s), iop);
+#endif
+}
+
+
+
+	void
+#if has_prototypes
+fvfprintf(FILE *stream, char const *format, va_list args)
+#else
+	fvfprintf(stream,format,args) FILE *stream; char *format; va_list args;
+#endif
+/* like vfprintf, except abort program on error */
+{
+#if has_vfprintf
+	if (vfprintf(stream, format, args) < 0)
+		Oerror();
+#else
+#	if has__doprintf
+		_doprintf(stream, format, args);
+#	else
+#	if has__doprnt
+		_doprnt(format, args, stream);
+#	else
+		int *a = (int *)args;
+		VOID fprintf(stream, format,
+			a[0], a[1], a[2], a[3], a[4],
+			a[5], a[6], a[7], a[8], a[9]
+		);
+#	endif
+#	endif
+	if (ferror(stream))
+		Oerror();
+#endif
+}
+
+#if has_prototypes
+	void
+aprintf(FILE *iop, char const *fmt, ...)
+#else
+	/*VARARGS2*/ void
+aprintf(iop, fmt, va_alist)
+FILE *iop;
+char const *fmt;
+va_dcl
+#endif
+/* Function: formatted output. Same as fprintf in stdio,
+ * but aborts program on error
+ */
+{
+	va_list ap;
+	vararg_start(ap, fmt);
+	fvfprintf(iop, fmt, ap);
+	va_end(ap);
+}
+
+
+
+#ifdef LEXDB
+/* test program reading a stream of lexemes and printing the tokens.
+ */
+
+
+
+	int
+main(argc,argv)
+int argc; char * argv[];
+{
+        cmdid="lextest";
+        if (argc<2) {
+		aputs("No input file\n",stderr);
+		exitmain(EXIT_FAILURE);
+        }
+	if (!(finptr=Iopen(argv[1], FOPEN_R, (struct stat*)0))) {
+		faterror("can't open input file %s",argv[1]);
+        }
+        Lexinit();
+	while (!eoflex()) {
+        switch (nexttok) {
+
+        case ID:
+                VOID printf("ID: %s",NextString);
+                break;
+
+        case NUM:
+		if (hshenter)
+                   VOID printf("NUM: %s, index: %d",nexthsh->num, nexthsh-hshtab);
+                else
+                   VOID printf("NUM, unentered: %s",NextString);
+                hshenter = !hshenter; /*alternate between dates and numbers*/
+                break;
+
+        case COLON:
+                VOID printf("COLON"); break;
+
+        case SEMI:
+                VOID printf("SEMI"); break;
+
+        case STRING:
+                readstring();
+                VOID printf("STRING"); break;
+
+        case UNKN:
+                VOID printf("UNKN"); break;
+
+        default:
+                VOID printf("DEFAULT"); break;
+        }
+        VOID printf(" | ");
+        nextlex();
+        }
+	exitmain(EXIT_SUCCESS);
+}
+
+void exiterr() { _exit(EXIT_FAILURE); }
+
+
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcsmap.c b/gnu/usr.bin/rcs/lib/rcsmap.c
new file mode 100644
index 0000000000000..89fb08daf3646
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsmap.c
@@ -0,0 +1,69 @@
+/* RCS map of character types */
+
+/* Copyright (C) 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1995 by Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#include "rcsbase.h"
+
+libId(mapId, "$FreeBSD$")
+
+/* map of character types */
+/* ISO 8859/1 (Latin-1) */
+enum tokens const ctab[] = {
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	SPACE,	SPACE,	NEWLN,	SPACE,	SPACE,	SPACE,	UNKN,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	SPACE,	IDCHAR,	IDCHAR,	IDCHAR,	DELIM,	IDCHAR,	IDCHAR,	IDCHAR,
+	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	DELIM,	IDCHAR,	PERIOD,	IDCHAR,
+	DIGIT,	DIGIT,	DIGIT,	DIGIT,	DIGIT,	DIGIT,	DIGIT,	DIGIT,
+	DIGIT,	DIGIT,	COLON,	SEMI,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	SBEGIN,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,
+	LETTER,	LETTER,	LETTER,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	IDCHAR,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,
+	Letter,	Letter,	Letter,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,	UNKN,
+	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,	IDCHAR,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	IDCHAR,
+	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	LETTER,	Letter,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	IDCHAR,
+	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter,	Letter
+};
diff --git a/gnu/usr.bin/rcs/lib/rcsrev.c b/gnu/usr.bin/rcs/lib/rcsrev.c
new file mode 100644
index 0000000000000..12c6c43006ac5
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsrev.c
@@ -0,0 +1,911 @@
+/* Handle RCS revision numbers.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.10  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.9  1995/06/01 16:23:43  eggert
+ * (cmpdate, normalizeyear): New functions work around MKS RCS incompatibility.
+ * (cmpnum, compartial): s[d] -> *(s+d) to work around Cray compiler bug.
+ * (genrevs, genbranch): cmpnum -> cmpdate
+ *
+ * Revision 5.8  1994/03/17 14:05:48  eggert
+ * Remove lint.
+ *
+ * Revision 5.7  1993/11/09 17:40:15  eggert
+ * Fix format string typos.
+ *
+ * Revision 5.6  1993/11/03 17:42:27  eggert
+ * Revision number `.N' now stands for `D.N', where D is the default branch.
+ * Add -z.  Improve quality of diagnostics.  Add `namedrev' for Name support.
+ *
+ * Revision 5.5  1992/07/28  16:12:44  eggert
+ * Identifiers may now start with a digit.  Avoid `unsigned'.
+ *
+ * Revision 5.4  1992/01/06  02:42:34  eggert
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.3  1991/08/19  03:13:55  eggert
+ * Add `-r$', `-rB.'.  Remove botches like `<now>' from messages.  Tune.
+ *
+ * Revision 5.2  1991/04/21  11:58:28  eggert
+ * Add tiprev().
+ *
+ * Revision 5.1  1991/02/25  07:12:43  eggert
+ * Avoid overflow when comparing revision numbers.
+ *
+ * Revision 5.0  1990/08/22  08:13:43  eggert
+ * Remove compile-time limits; use malloc instead.
+ * Ansify and Posixate.  Tune.
+ * Remove possibility of an internal error.  Remove lint.
+ *
+ * Revision 4.5  89/05/01  15:13:22  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.4  87/12/18  11:45:22  narten
+ * more lint cleanups. Also, the NOTREACHED comment is no longer necessary,
+ * since there's now a return value there with a value. (Guy Harris)
+ *
+ * Revision 4.3  87/10/18  10:38:42  narten
+ * Updating version numbers. Changes relative to version 1.1 actually
+ * relative to 4.1
+ *
+ * Revision 1.3  87/09/24  14:00:37  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:37  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/03/25  21:10:45  wft
+ * Only changed $Header to $Id.
+ *
+ * Revision 3.4  82/12/04  13:24:08  wft
+ * Replaced getdelta() with gettree().
+ *
+ * Revision 3.3  82/11/28  21:33:15  wft
+ * fixed compartial() and compnum() for nil-parameters; fixed nils
+ * in error messages. Testprogram output shortenend.
+ *
+ * Revision 3.2  82/10/18  21:19:47  wft
+ * renamed compnum->cmpnum, compnumfld->cmpnumfld,
+ * numericrevno->numricrevno.
+ *
+ * Revision 3.1  82/10/11  19:46:09  wft
+ * changed expandsym() to check for source==nil; returns zero length string
+ * in that case.
+ */
+
+#include "rcsbase.h"
+
+libId(revId, "$FreeBSD$")
+
+static char const *branchtip P((char const*));
+static char const *lookupsym P((char const*));
+static char const *normalizeyear P((char const*,char[5]));
+static struct hshentry *genbranch P((struct hshentry const*,char const*,int,char const*,char const*,char const*,struct hshentries**));
+static void absent P((char const*,int));
+static void cantfindbranch P((char const*,char const[datesize],char const*,char const*));
+static void store1 P((struct hshentries***,struct hshentry*));
+
+
+
+	int
+countnumflds(s)
+	char const *s;
+/* Given a pointer s to a dotted number (date or revision number),
+ * countnumflds returns the number of digitfields in s.
+ */
+{
+	register char const *sp;
+	register int count;
+	if (!(sp=s) || !*sp)
+		return 0;
+        count = 1;
+	do {
+                if (*sp++ == '.') count++;
+	} while (*sp);
+        return(count);
+}
+
+	void
+getbranchno(revno,branchno)
+	char const *revno;
+	struct buf *branchno;
+/* Given a revision number revno, getbranchno copies the number of the branch
+ * on which revno is into branchno. If revno itself is a branch number,
+ * it is copied unchanged.
+ */
+{
+	register int numflds;
+	register char *tp;
+
+	bufscpy(branchno, revno);
+        numflds=countnumflds(revno);
+	if (!(numflds & 1)) {
+		tp = branchno->string;
+		while (--numflds)
+			while (*tp++ != '.')
+				continue;
+                *(tp-1)='\0';
+        }
+}
+
+
+
+int cmpnum(num1, num2)
+	char const *num1, *num2;
+/* compares the two dotted numbers num1 and num2 lexicographically
+ * by field. Individual fields are compared numerically.
+ * returns <0, 0, >0 if num1<num2, num1==num2, and num1>num2, resp.
+ * omitted fields are assumed to be higher than the existing ones.
+*/
+{
+	register char const *s1, *s2;
+	register size_t d1, d2;
+	register int r;
+
+	s1 = num1 ? num1 : "";
+	s2 = num2 ? num2 : "";
+
+	for (;;) {
+		/* Give precedence to shorter one.  */
+		if (!*s1)
+			return (unsigned char)*s2;
+		if (!*s2)
+			return -1;
+
+		/* Strip leading zeros, then find number of digits.  */
+		while (*s1=='0') ++s1;
+		while (*s2=='0') ++s2;
+		for (d1=0; isdigit(*(s1+d1)); d1++) continue;
+		for (d2=0; isdigit(*(s2+d2)); d2++) continue;
+
+		/* Do not convert to integer; it might overflow!  */
+		if (d1 != d2)
+			return d1<d2 ? -1 : 1;
+		if ((r = memcmp(s1, s2, d1)))
+			return r;
+		s1 += d1;
+		s2 += d1;
+
+                /* skip '.' */
+		if (*s1) s1++;
+		if (*s2) s2++;
+	}
+}
+
+
+
+int cmpnumfld(num1, num2, fld)
+	char const *num1, *num2;
+	int fld;
+/* Compare the two dotted numbers at field fld.
+ * num1 and num2 must have at least fld fields.
+ * fld must be positive.
+*/
+{
+	register char const *s1, *s2;
+	register size_t d1, d2;
+
+	s1 = num1;
+	s2 = num2;
+        /* skip fld-1 fields */
+	while (--fld) {
+		while (*s1++ != '.')
+			continue;
+		while (*s2++ != '.')
+			continue;
+	}
+        /* Now s1 and s2 point to the beginning of the respective fields */
+	while (*s1=='0') ++s1;  for (d1=0; isdigit(*(s1+d1)); d1++) continue;
+	while (*s2=='0') ++s2;  for (d2=0; isdigit(*(s2+d2)); d2++) continue;
+
+	return d1<d2 ? -1 : d1==d2 ? memcmp(s1,s2,d1) : 1;
+}
+
+
+	int
+cmpdate(d1, d2)
+	char const *d1, *d2;
+/*
+* Compare the two dates.  This is just like cmpnum,
+* except that for compatibility with old versions of RCS,
+* 1900 is added to dates with two-digit years.
+*/
+{
+	char year1[5], year2[5];
+	int r = cmpnumfld(normalizeyear(d1,year1), normalizeyear(d2,year2), 1);
+
+	if (r)
+		return r;
+	else {
+		while (isdigit(*d1)) d1++;  d1 += *d1=='.';
+		while (isdigit(*d2)) d2++;  d2 += *d2=='.';
+		return cmpnum(d1, d2);
+	}
+}
+
+	static char const *
+normalizeyear(date, year)
+	char const *date;
+	char year[5];
+{
+	if (isdigit(date[0]) && isdigit(date[1]) && !isdigit(date[2])) {
+		year[0] = '1';
+		year[1] = '9';
+		year[2] = date[0];
+		year[3] = date[1];
+		year[4] = 0;
+		return year;
+	} else
+		return date;
+}
+
+
+	static void
+cantfindbranch(revno, date, author, state)
+	char const *revno, date[datesize], *author, *state;
+{
+	char datebuf[datesize + zonelenmax];
+
+	rcserror("No revision on branch %s has%s%s%s%s%s%s.",
+		revno,
+		date ? " a date before " : "",
+		date ? date2str(date,datebuf) : "",
+		author ? " and author "+(date?0:4) : "",
+		author ? author : "",
+		state ? " and state "+(date||author?0:4) : "",
+		state ? state : ""
+	);
+}
+
+	static void
+absent(revno, field)
+	char const *revno;
+	int field;
+{
+	struct buf t;
+	bufautobegin(&t);
+	rcserror("%s %s absent", field&1?"revision":"branch",
+		partialno(&t,revno,field)
+	);
+	bufautoend(&t);
+}
+
+
+	int
+compartial(num1, num2, length)
+	char const *num1, *num2;
+	int length;
+
+/*   compare the first "length" fields of two dot numbers;
+     the omitted field is considered to be larger than any number  */
+/*   restriction:  at least one number has length or more fields   */
+
+{
+	register char const *s1, *s2;
+	register size_t d1, d2;
+	register int r;
+
+        s1 = num1;      s2 = num2;
+	if (!s1) return 1;
+	if (!s2) return -1;
+
+	for (;;) {
+	    if (!*s1) return 1;
+	    if (!*s2) return -1;
+
+	    while (*s1=='0') ++s1; for (d1=0; isdigit(*(s1+d1)); d1++) continue;
+	    while (*s2=='0') ++s2; for (d2=0; isdigit(*(s2+d2)); d2++) continue;
+
+	    if (d1 != d2)
+		    return d1<d2 ? -1 : 1;
+	    if ((r = memcmp(s1, s2, d1)))
+		    return r;
+	    if (!--length)
+		    return 0;
+
+	    s1 += d1;
+	    s2 += d1;
+
+	    if (*s1 == '.') s1++;
+            if (*s2 == '.') s2++;
+	}
+}
+
+
+char * partialno(rev1,rev2,length)
+	struct buf *rev1;
+	char const *rev2;
+	register int length;
+/* Function: Copies length fields of revision number rev2 into rev1.
+ * Return rev1's string.
+ */
+{
+	register char *r1;
+
+	bufscpy(rev1, rev2);
+	r1 = rev1->string;
+        while (length) {
+		while (*r1!='.' && *r1)
+			++r1;
+		++r1;
+                length--;
+        }
+        /* eliminate last '.'*/
+        *(r1-1)='\0';
+	return rev1->string;
+}
+
+
+
+
+	static void
+store1(store, next)
+	struct hshentries ***store;
+	struct hshentry *next;
+/*
+ * Allocate a new list node that addresses NEXT.
+ * Append it to the list that **STORE is the end pointer of.
+ */
+{
+	register struct hshentries *p;
+
+	p = ftalloc(struct hshentries);
+	p->first = next;
+	**store = p;
+	*store = &p->rest;
+}
+
+struct hshentry * genrevs(revno,date,author,state,store)
+	char const *revno, *date, *author, *state;
+	struct hshentries **store;
+/* Function: finds the deltas needed for reconstructing the
+ * revision given by revno, date, author, and state, and stores pointers
+ * to these deltas into a list whose starting address is given by store.
+ * The last delta (target delta) is returned.
+ * If the proper delta could not be found, 0 is returned.
+ */
+{
+	int length;
+        register struct hshentry * next;
+        int result;
+	char const *branchnum;
+	struct buf t;
+	char datebuf[datesize + zonelenmax];
+
+	bufautobegin(&t);
+
+	if (!(next = Head)) {
+		rcserror("RCS file empty");
+		goto norev;
+        }
+
+        length = countnumflds(revno);
+
+        if (length >= 1) {
+                /* at least one field; find branch exactly */
+		while ((result=cmpnumfld(revno,next->num,1)) < 0) {
+			store1(&store, next);
+                        next = next->next;
+			if (!next) {
+			    rcserror("branch number %s too low", partialno(&t,revno,1));
+			    goto norev;
+			}
+                }
+
+		if (result>0) {
+			absent(revno, 1);
+			goto norev;
+		}
+        }
+        if (length<=1){
+                /* pick latest one on given branch */
+                branchnum = next->num; /* works even for empty revno*/
+		while (next &&
+		       cmpnumfld(branchnum,next->num,1) == 0 &&
+		       (
+			(date && cmpdate(date,next->date) < 0) ||
+			(author && strcmp(author,next->author) != 0) ||
+			(state && strcmp(state,next->state) != 0)
+		       )
+		      )
+		{
+			store1(&store, next);
+                        next=next->next;
+                }
+		if (!next ||
+                    (cmpnumfld(branchnum,next->num,1)!=0))/*overshot*/ {
+			cantfindbranch(
+				length ? revno : partialno(&t,branchnum,1),
+				date, author, state
+			);
+			goto norev;
+                } else {
+			store1(&store, next);
+                }
+		*store = 0;
+                return next;
+        }
+
+        /* length >=2 */
+        /* find revision; may go low if length==2*/
+	while ((result=cmpnumfld(revno,next->num,2)) < 0  &&
+               (cmpnumfld(revno,next->num,1)==0) ) {
+		store1(&store, next);
+                next = next->next;
+		if (!next)
+			break;
+        }
+
+	if (!next || cmpnumfld(revno,next->num,1) != 0) {
+		rcserror("revision number %s too low", partialno(&t,revno,2));
+		goto norev;
+        }
+        if ((length>2) && (result!=0)) {
+		absent(revno, 2);
+		goto norev;
+        }
+
+        /* print last one */
+	store1(&store, next);
+
+        if (length>2)
+                return genbranch(next,revno,length,date,author,state,store);
+        else { /* length == 2*/
+		if (date && cmpdate(date,next->date)<0) {
+			rcserror("Revision %s has date %s.",
+				next->num,
+				date2str(next->date, datebuf)
+			);
+			return 0;
+		}
+		if (author && strcmp(author,next->author)!=0) {
+			rcserror("Revision %s has author %s.",
+				next->num, next->author
+			);
+			return 0;
+                }
+		if (state && strcmp(state,next->state)!=0) {
+			rcserror("Revision %s has state %s.",
+				next->num,
+				next->state ? next->state : "<empty>"
+			);
+			return 0;
+                }
+		*store = 0;
+                return next;
+        }
+
+    norev:
+	bufautoend(&t);
+	return 0;
+}
+
+
+
+
+	static struct hshentry *
+genbranch(bpoint, revno, length, date, author, state, store)
+	struct hshentry const *bpoint;
+	char const *revno;
+	int length;
+	char const *date, *author, *state;
+	struct hshentries **store;
+/* Function: given a branchpoint, a revision number, date, author, and state,
+ * genbranch finds the deltas necessary to reconstruct the given revision
+ * from the branch point on.
+ * Pointers to the found deltas are stored in a list beginning with store.
+ * revno must be on a side branch.
+ * Return 0 on error.
+ */
+{
+	int field;
+        register struct hshentry * next, * trail;
+	register struct branchhead const *bhead;
+        int result;
+	struct buf t;
+	char datebuf[datesize + zonelenmax];
+
+	field = 3;
+        bhead = bpoint->branches;
+
+	do {
+		if (!bhead) {
+			bufautobegin(&t);
+			rcserror("no side branches present for %s",
+				partialno(&t,revno,field-1)
+			);
+			bufautoend(&t);
+			return 0;
+		}
+
+                /*find branch head*/
+                /*branches are arranged in increasing order*/
+		while (0 < (result=cmpnumfld(revno,bhead->hsh->num,field))) {
+                        bhead = bhead->nextbranch;
+			if (!bhead) {
+			    bufautobegin(&t);
+			    rcserror("branch number %s too high",
+				partialno(&t,revno,field)
+			    );
+			    bufautoend(&t);
+			    return 0;
+			}
+                }
+
+		if (result<0) {
+		    absent(revno, field);
+		    return 0;
+		}
+
+                next = bhead->hsh;
+                if (length==field) {
+                        /* pick latest one on that branch */
+			trail = 0;
+			do { if ((!date || cmpdate(date,next->date)>=0) &&
+				 (!author || strcmp(author,next->author)==0) &&
+				 (!state || strcmp(state,next->state)==0)
+                             ) trail = next;
+                             next=next->next;
+			} while (next);
+
+			if (!trail) {
+			     cantfindbranch(revno, date, author, state);
+			     return 0;
+                        } else { /* print up to last one suitable */
+                             next = bhead->hsh;
+                             while (next!=trail) {
+				  store1(&store, next);
+                                  next=next->next;
+                             }
+			     store1(&store, next);
+                        }
+			*store = 0;
+                        return next;
+                }
+
+                /* length > field */
+                /* find revision */
+                /* check low */
+                if (cmpnumfld(revno,next->num,field+1)<0) {
+			bufautobegin(&t);
+			rcserror("revision number %s too low",
+				partialno(&t,revno,field+1)
+			);
+			bufautoend(&t);
+			return 0;
+                }
+		do {
+			store1(&store, next);
+                        trail = next;
+                        next = next->next;
+		} while (next && cmpnumfld(revno,next->num,field+1)>=0);
+
+                if ((length>field+1) &&  /*need exact hit */
+                    (cmpnumfld(revno,trail->num,field+1) !=0)){
+			absent(revno, field+1);
+			return 0;
+                }
+                if (length == field+1) {
+			if (date && cmpdate(date,trail->date)<0) {
+				rcserror("Revision %s has date %s.",
+					trail->num,
+					date2str(trail->date, datebuf)
+				);
+				return 0;
+                        }
+			if (author && strcmp(author,trail->author)!=0) {
+				rcserror("Revision %s has author %s.",
+					trail->num, trail->author
+				);
+				return 0;
+                        }
+			if (state && strcmp(state,trail->state)!=0) {
+				rcserror("Revision %s has state %s.",
+					trail->num,
+					trail->state ? trail->state : "<empty>"
+				);
+				return 0;
+                        }
+                }
+                bhead = trail->branches;
+
+	} while ((field+=2) <= length);
+	*store = 0;
+        return trail;
+}
+
+
+	static char const *
+lookupsym(id)
+	char const *id;
+/* Function: looks up id in the list of symbolic names starting
+ * with pointer SYMBOLS, and returns a pointer to the corresponding
+ * revision number.  Return 0 if not present.
+ */
+{
+	register struct assoc const *next;
+	for (next = Symbols;  next;  next = next->nextassoc)
+                if (strcmp(id, next->symbol)==0)
+			return next->num;
+	return 0;
+}
+
+int expandsym(source, target)
+	char const *source;
+	struct buf *target;
+/* Function: Source points to a revision number. Expandsym copies
+ * the number to target, but replaces all symbolic fields in the
+ * source number with their numeric values.
+ * Expand a branch followed by `.' to the latest revision on that branch.
+ * Ignore `.' after a revision.  Remove leading zeros.
+ * returns false on error;
+ */
+{
+	return fexpandsym(source, target, (RILE*)0);
+}
+
+	int
+fexpandsym(source, target, fp)
+	char const *source;
+	struct buf *target;
+	RILE *fp;
+/* Same as expandsym, except if FP is nonzero, it is used to expand KDELIM.  */
+{
+	register char const *sp, *bp;
+	register char *tp;
+	char const *tlim;
+	int dots;
+
+	sp = source;
+	bufalloc(target, 1);
+	tp = target->string;
+	if (!sp || !*sp) { /* Accept 0 pointer as a legal value.  */
+                *tp='\0';
+                return true;
+        }
+	if (sp[0] == KDELIM  &&  !sp[1]) {
+		if (!getoldkeys(fp))
+			return false;
+		if (!*prevrev.string) {
+			workerror("working file lacks revision number");
+			return false;
+		}
+		bufscpy(target, prevrev.string);
+		return true;
+	}
+	tlim = tp + target->size;
+	dots = 0;
+
+	for (;;) {
+		register char *p = tp;
+		size_t s = tp - target->string;
+		int id = false;
+		for (;;) {
+		    switch (ctab[(unsigned char)*sp]) {
+			case IDCHAR:
+			case LETTER:
+			case Letter:
+			    id = true;
+			    /* fall into */
+			case DIGIT:
+			    if (tlim <= p)
+				    p = bufenlarge(target, &tlim);
+			    *p++ = *sp++;
+			    continue;
+
+			default:
+			    break;
+		    }
+		    break;
+		}
+		if (tlim <= p)
+			p = bufenlarge(target, &tlim);
+		*p = 0;
+		tp = target->string + s;
+
+		if (id) {
+			bp = lookupsym(tp);
+			if (!bp) {
+				rcserror("Symbolic name `%s' is undefined.",tp);
+                                return false;
+                        }
+		} else {
+			/* skip leading zeros */
+			for (bp = tp;  *bp=='0' && isdigit(bp[1]);  bp++)
+				continue;
+
+			if (!*bp)
+			    if (s || *sp!='.')
+				break;
+			    else {
+				/* Insert default branch before initial `.'.  */
+				char const *b;
+				if (Dbranch)
+				    b = Dbranch;
+				else if (Head)
+				    b = Head->num;
+				else
+				    break;
+				getbranchno(b, target);
+				bp = tp = target->string;
+				tlim = tp + target->size;
+			    }
+		}
+
+		while ((*tp++ = *bp++))
+			if (tlim <= tp)
+				tp = bufenlarge(target, &tlim);
+
+		switch (*sp++) {
+		    case '\0':
+			return true;
+
+		    case '.':
+			if (!*sp) {
+				if (dots & 1)
+					break;
+				if (!(bp = branchtip(target->string)))
+					return false;
+				bufscpy(target, bp);
+				return true;
+			}
+			++dots;
+			tp[-1] = '.';
+			continue;
+		}
+		break;
+        }
+
+	rcserror("improper revision number: %s", source);
+	return false;
+}
+
+	char const *
+namedrev(name, delta)
+	char const *name;
+	struct hshentry *delta;
+/* Yield NAME if it names DELTA, 0 otherwise.  */
+{
+	if (name) {
+		char const *id = 0, *p, *val;
+		for (p = name;  ;  p++)
+			switch (ctab[(unsigned char)*p]) {
+				case IDCHAR:
+				case LETTER:
+				case Letter:
+					id = name;
+					break;
+
+				case DIGIT:
+					break;
+
+				case UNKN:
+					if (!*p && id &&
+						(val = lookupsym(id)) &&
+						strcmp(val, delta->num) == 0
+					)
+						return id;
+					/* fall into */
+				default:
+					return 0;
+			}
+	}
+	return 0;
+}
+
+	static char const *
+branchtip(branch)
+	char const *branch;
+{
+	struct hshentry *h;
+	struct hshentries *hs;
+
+	h  =  genrevs(branch, (char*)0, (char*)0, (char*)0, &hs);
+	return h ? h->num : (char const*)0;
+}
+
+	char const *
+tiprev()
+{
+	return Dbranch ? branchtip(Dbranch) : Head ? Head->num : (char const*)0;
+}
+
+
+
+#ifdef REVTEST
+
+/*
+* Test the routines that generate a sequence of delta numbers
+* needed to regenerate a given delta.
+*/
+
+char const cmdid[] = "revtest";
+
+	int
+main(argc,argv)
+int argc; char * argv[];
+{
+	static struct buf numricrevno;
+	char symrevno[100];       /* used for input of revision numbers */
+        char author[20];
+        char state[20];
+        char date[20];
+	struct hshentries *gendeltas;
+        struct hshentry * target;
+        int i;
+
+        if (argc<2) {
+		aputs("No input file\n",stderr);
+		exitmain(EXIT_FAILURE);
+        }
+	if (!(finptr=Iopen(argv[1], FOPEN_R, (struct stat*)0))) {
+		faterror("can't open input file %s", argv[1]);
+        }
+        Lexinit();
+        getadmin();
+
+        gettree();
+
+        getdesc(false);
+
+        do {
+                /* all output goes to stderr, to have diagnostics and       */
+                /* errors in sequence.                                      */
+		aputs("\nEnter revision number or <return> or '.': ",stderr);
+		if (!fgets(symrevno, 100, stdin)) break;
+                if (*symrevno == '.') break;
+		aprintf(stderr,"%s;\n",symrevno);
+		expandsym(symrevno,&numricrevno);
+		aprintf(stderr,"expanded number: %s; ",numricrevno.string);
+		aprintf(stderr,"Date: ");
+		fgets(date, 20, stdin); aprintf(stderr,"%s; ",date);
+		aprintf(stderr,"Author: ");
+		fgets(author, 20, stdin); aprintf(stderr,"%s; ",author);
+		aprintf(stderr,"State: ");
+		fgets(state, 20, stdin); aprintf(stderr, "%s;\n", state);
+		target = genrevs(numricrevno.string, *date?date:(char *)0, *author?author:(char *)0,
+				 *state?state:(char*)0, &gendeltas);
+		if (target) {
+			while (gendeltas) {
+				aprintf(stderr,"%s\n",gendeltas->first->num);
+				gendeltas = gendeltas->next;
+                        }
+                }
+        } while (true);
+	aprintf(stderr,"done\n");
+	exitmain(EXIT_SUCCESS);
+}
+
+void exiterr() { _exit(EXIT_FAILURE); }
+
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcssyn.c b/gnu/usr.bin/rcs/lib/rcssyn.c
new file mode 100644
index 0000000000000..07f155bfb8ea8
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcssyn.c
@@ -0,0 +1,681 @@
+/* RCS file syntactic analysis */
+
+/******************************************************************************
+ *                       Syntax Analysis.
+ *                       Keyword table
+ *                       Testprogram: define SYNTEST
+ *                       Compatibility with Release 2: define COMPAT2=1
+ ******************************************************************************
+ */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.15  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.14  1995/06/01 16:23:43  eggert
+ * (expand_names): Add "b" for -kb.
+ * (getdelta): Don't strip leading "19" from MKS RCS dates; see cmpdate.
+ *
+ * Revision 5.13  1994/03/20 04:52:58  eggert
+ * Remove lint.
+ *
+ * Revision 5.12  1993/11/03 17:42:27  eggert
+ * Parse MKS RCS dates; ignore \r in diff control lines.
+ * Don't discard ignored phrases.  Improve quality of diagnostics.
+ *
+ * Revision 5.11  1992/07/28  16:12:44  eggert
+ * Avoid `unsigned'.  Statement macro names now end in _.
+ *
+ * Revision 5.10  1992/01/24  18:44:19  eggert
+ * Move put routines to rcsgen.c.
+ *
+ * Revision 5.9  1992/01/06  02:42:34  eggert
+ * ULONG_MAX/10 -> ULONG_MAX_OVER_10
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Tune.
+ *
+ * Revision 5.7  1991/04/21  11:58:29  eggert
+ * Disambiguate names on shortname hosts.
+ * Fix errno bug.  Add MS-DOS support.
+ *
+ * Revision 5.6  1991/02/28  19:18:51  eggert
+ * Fix null termination bug in reporting keyword expansion.
+ *
+ * Revision 5.5  1991/02/25  07:12:44  eggert
+ * Check diff output more carefully; avoid overflow.
+ *
+ * Revision 5.4  1990/11/01  05:28:48  eggert
+ * When ignoring unknown phrases, copy them to the output RCS file.
+ * Permit arbitrary data in logs and comment leaders.
+ * Don't check for nontext on initial checkin.
+ *
+ * Revision 5.3  1990/09/20  07:58:32  eggert
+ * Remove the test for non-text bytes; it caused more pain than it cured.
+ *
+ * Revision 5.2  1990/09/04  08:02:30  eggert
+ * Parse RCS files with no revisions.
+ * Don't strip leading white space from diff commands.  Count RCS lines better.
+ *
+ * Revision 5.1  1990/08/29  07:14:06  eggert
+ * Add -kkvl.  Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:13:44  eggert
+ * Try to parse future RCS formats without barfing.
+ * Add -k.  Don't require final newline.
+ * Remove compile-time limits; use malloc instead.
+ * Don't output branch keyword if there's no default branch,
+ * because RCS version 3 doesn't understand it.
+ * Tune.  Remove lint.
+ * Add support for ISO 8859.  Ansify and Posixate.
+ * Check that a newly checked-in file is acceptable as input to 'diff'.
+ * Check diff's output.
+ *
+ * Revision 4.6  89/05/01  15:13:32  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.5  88/08/09  19:13:21  eggert
+ * Allow cc -R; remove lint.
+ *
+ * Revision 4.4  87/12/18  11:46:16  narten
+ * more lint cleanups (Guy Harris)
+ *
+ * Revision 4.3  87/10/18  10:39:36  narten
+ * Updating version numbers. Changes relative to 1.1 actually relative to
+ * 4.1
+ *
+ * Revision 1.3  87/09/24  14:00:49  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:40  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/03/28  11:38:49  wft
+ * Added parsing and printing of default branch.
+ *
+ * Revision 3.6  83/01/15  17:46:50  wft
+ * Changed readdelta() to initialize selector and log-pointer.
+ * Changed puttree to check for selector==DELETE; putdtext() uses DELNUMFORM.
+ *
+ * Revision 3.5  82/12/08  21:58:58  wft
+ * renamed Commentleader to Commleader.
+ *
+ * Revision 3.4  82/12/04  13:24:40  wft
+ * Added routine gettree(), which updates keeplock after reading the
+ * delta tree.
+ *
+ * Revision 3.3  82/11/28  21:30:11  wft
+ * Reading and printing of Suffix removed; version COMPAT2 skips the
+ * Suffix for files of release 2 format. Fixed problems with printing nil.
+ *
+ * Revision 3.2  82/10/18  21:18:25  wft
+ * renamed putdeltatext to putdtext.
+ *
+ * Revision 3.1  82/10/11  19:45:11  wft
+ * made sure getc() returns into an integer.
+ */
+
+
+
+/* version COMPAT2 reads files of the format of release 2 and 3, but
+ * generates files of release 3 format. Need not be defined if no
+ * old RCS files generated with release 2 exist.
+ */
+
+#include "rcsbase.h"
+
+libId(synId, "$FreeBSD$")
+
+static char const *getkeyval P((char const*,enum tokens,int));
+static int getdelta P((void));
+static int strn2expmode P((char const*,size_t));
+static struct hshentry *getdnum P((void));
+static void badDiffOutput P((char const*)) exiting;
+static void diffLineNumberTooLarge P((char const*)) exiting;
+static void getsemi P((char const*));
+
+/* keyword table */
+
+char const
+	Kaccess[]   = "access",
+	Kauthor[]   = "author",
+	Kbranch[]   = "branch",
+	Kcomment[]  = "comment",
+	Kdate[]     = "date",
+	Kdesc[]     = "desc",
+	Kexpand[]   = "expand",
+	Khead[]     = "head",
+	Klocks[]    = "locks",
+	Klog[]      = "log",
+	Knext[]     = "next",
+	Kstate[]    = "state",
+	Kstrict[]   = "strict",
+	Ksymbols[]  = "symbols",
+	Ktext[]     = "text";
+
+static char const
+#if COMPAT2
+	Ksuffix[]   = "suffix",
+#endif
+	K_branches[]= "branches";
+
+static struct buf Commleader;
+struct cbuf Comment;
+struct cbuf Ignored;
+struct access   * AccessList;
+struct assoc    * Symbols;
+struct rcslock *Locks;
+int		  Expand;
+int               StrictLocks;
+struct hshentry * Head;
+char const      * Dbranch;
+int TotalDeltas;
+
+
+	static void
+getsemi(key)
+	char const *key;
+/* Get a semicolon to finish off a phrase started by KEY.  */
+{
+	if (!getlex(SEMI))
+		fatserror("missing ';' after '%s'", key);
+}
+
+	static struct hshentry *
+getdnum()
+/* Get a delta number.  */
+{
+	register struct hshentry *delta = getnum();
+	if (delta && countnumflds(delta->num)&1)
+		fatserror("%s isn't a delta number", delta->num);
+	return delta;
+}
+
+
+	void
+getadmin()
+/* Read an <admin> and initialize the appropriate global variables.  */
+{
+	register char const *id;
+        struct access   * newaccess;
+        struct assoc    * newassoc;
+	struct rcslock *newlock;
+        struct hshentry * delta;
+	struct access **LastAccess;
+	struct assoc **LastSymbol;
+	struct rcslock **LastLock;
+	struct buf b;
+	struct cbuf cb;
+
+        TotalDeltas=0;
+
+	getkey(Khead);
+	Head = getdnum();
+	getsemi(Khead);
+
+	Dbranch = 0;
+	if (getkeyopt(Kbranch)) {
+		if ((delta = getnum()))
+			Dbranch = delta->num;
+		getsemi(Kbranch);
+        }
+
+
+#if COMPAT2
+        /* read suffix. Only in release 2 format */
+	if (getkeyopt(Ksuffix)) {
+                if (nexttok==STRING) {
+			readstring(); nextlex(); /* Throw away the suffix.  */
+		} else if (nexttok==ID) {
+                        nextlex();
+                }
+		getsemi(Ksuffix);
+        }
+#endif
+
+	getkey(Kaccess);
+	LastAccess = &AccessList;
+	while ((id = getid())) {
+		newaccess = ftalloc(struct access);
+                newaccess->login = id;
+		*LastAccess = newaccess;
+		LastAccess = &newaccess->nextaccess;
+        }
+	*LastAccess = 0;
+	getsemi(Kaccess);
+
+	getkey(Ksymbols);
+	LastSymbol = &Symbols;
+        while ((id = getid())) {
+                if (!getlex(COLON))
+			fatserror("missing ':' in symbolic name definition");
+                if (!(delta=getnum())) {
+			fatserror("missing number in symbolic name definition");
+                } else { /*add new pair to association list*/
+			newassoc = ftalloc(struct assoc);
+                        newassoc->symbol=id;
+			newassoc->num = delta->num;
+			*LastSymbol = newassoc;
+			LastSymbol = &newassoc->nextassoc;
+                }
+        }
+	*LastSymbol = 0;
+	getsemi(Ksymbols);
+
+	getkey(Klocks);
+	LastLock = &Locks;
+        while ((id = getid())) {
+                if (!getlex(COLON))
+			fatserror("missing ':' in lock");
+		if (!(delta=getdnum())) {
+			fatserror("missing number in lock");
+                } else { /*add new pair to lock list*/
+			newlock = ftalloc(struct rcslock);
+                        newlock->login=id;
+                        newlock->delta=delta;
+			*LastLock = newlock;
+			LastLock = &newlock->nextlock;
+                }
+        }
+	*LastLock = 0;
+	getsemi(Klocks);
+
+	if ((StrictLocks = getkeyopt(Kstrict)))
+		getsemi(Kstrict);
+
+	clear_buf(&Comment);
+	if (getkeyopt(Kcomment)) {
+		if (nexttok==STRING) {
+			Comment = savestring(&Commleader);
+			nextlex();
+		}
+		getsemi(Kcomment);
+        }
+
+	Expand = KEYVAL_EXPAND;
+	if (getkeyopt(Kexpand)) {
+		if (nexttok==STRING) {
+			bufautobegin(&b);
+			cb = savestring(&b);
+			if ((Expand = strn2expmode(cb.string,cb.size)) < 0)
+			    fatserror("unknown expand mode %.*s",
+				(int)cb.size, cb.string
+			    );
+			bufautoend(&b);
+			nextlex();
+		}
+		getsemi(Kexpand);
+        }
+	Ignored = getphrases(Kdesc);
+}
+
+char const *const expand_names[] = {
+	/* These must agree with *_EXPAND in rcsbase.h.  */
+	"kv", "kvl", "k", "v", "o", "b",
+	0
+};
+
+	int
+str2expmode(s)
+	char const *s;
+/* Yield expand mode corresponding to S, or -1 if bad.  */
+{
+	return strn2expmode(s, strlen(s));
+}
+
+	static int
+strn2expmode(s, n)
+	char const *s;
+	size_t n;
+{
+	char const *const *p;
+
+	for (p = expand_names;  *p;  ++p)
+		if (memcmp(*p,s,n) == 0  &&  !(*p)[n])
+			return p - expand_names;
+	return -1;
+}
+
+
+	void
+ignorephrases(key)
+	const char *key;
+/*
+* Ignore a series of phrases that do not start with KEY.
+* Stop when the next phrase starts with a token that is not an identifier,
+* or is KEY.
+*/
+{
+	for (;;) {
+		nextlex();
+		if (nexttok != ID  ||  strcmp(NextString,key) == 0)
+			break;
+		warnignore();
+		hshenter=false;
+		for (;; nextlex()) {
+			switch (nexttok) {
+				case SEMI: hshenter=true; break;
+				case ID:
+				case NUM: ffree1(NextString); continue;
+				case STRING: readstring(); continue;
+				default: continue;
+			}
+			break;
+		}
+	}
+}
+
+
+	static int
+getdelta()
+/* Function: reads a delta block.
+ * returns false if the current block does not start with a number.
+ */
+{
+        register struct hshentry * Delta, * num;
+	struct branchhead **LastBranch, *NewBranch;
+
+	if (!(Delta = getdnum()))
+		return false;
+
+        hshenter = false; /*Don't enter dates into hashtable*/
+	Delta->date = getkeyval(Kdate, NUM, false);
+        hshenter=true;    /*reset hshenter for revision numbers.*/
+
+        Delta->author = getkeyval(Kauthor, ID, false);
+
+        Delta->state = getkeyval(Kstate, ID, true);
+
+	getkey(K_branches);
+	LastBranch = &Delta->branches;
+	while ((num = getdnum())) {
+		NewBranch = ftalloc(struct branchhead);
+                NewBranch->hsh = num;
+		*LastBranch = NewBranch;
+		LastBranch = &NewBranch->nextbranch;
+        }
+	*LastBranch = 0;
+	getsemi(K_branches);
+
+	getkey(Knext);
+	Delta->next = num = getdnum();
+	getsemi(Knext);
+	Delta->lockedby = 0;
+	Delta->log.string = 0;
+	Delta->selector = true;
+	Delta->ig = getphrases(Kdesc);
+        TotalDeltas++;
+        return (true);
+}
+
+
+	void
+gettree()
+/* Function: Reads in the delta tree with getdelta(), then
+ * updates the lockedby fields.
+ */
+{
+	struct rcslock const *currlock;
+
+	while (getdelta())
+		continue;
+        currlock=Locks;
+        while (currlock) {
+                currlock->delta->lockedby = currlock->login;
+                currlock = currlock->nextlock;
+        }
+}
+
+
+	void
+getdesc(prdesc)
+int  prdesc;
+/* Function: read in descriptive text
+ * nexttok is not advanced afterwards.
+ * If prdesc is set, the text is printed to stdout.
+ */
+{
+
+	getkeystring(Kdesc);
+        if (prdesc)
+                printstring();  /*echo string*/
+        else    readstring();   /*skip string*/
+}
+
+
+
+
+
+
+	static char const *
+getkeyval(keyword, token, optional)
+	char const *keyword;
+	enum tokens token;
+	int optional;
+/* reads a pair of the form
+ * <keyword> <token> ;
+ * where token is one of <id> or <num>. optional indicates whether
+ * <token> is optional. A pointer to
+ * the actual character string of <id> or <num> is returned.
+ */
+{
+	register char const *val = 0;
+
+	getkey(keyword);
+        if (nexttok==token) {
+                val = NextString;
+                nextlex();
+        } else {
+		if (!optional)
+			fatserror("missing %s", keyword);
+        }
+	getsemi(keyword);
+        return(val);
+}
+
+
+	void
+unexpected_EOF()
+{
+	rcsfaterror("unexpected EOF in diff output");
+}
+
+	void
+initdiffcmd(dc)
+	register struct diffcmd *dc;
+/* Initialize *dc suitably for getdiffcmd(). */
+{
+	dc->adprev = 0;
+	dc->dafter = 0;
+}
+
+	static void
+badDiffOutput(buf)
+	char const *buf;
+{
+	rcsfaterror("bad diff output line: %s", buf);
+}
+
+	static void
+diffLineNumberTooLarge(buf)
+	char const *buf;
+{
+	rcsfaterror("diff line number too large: %s", buf);
+}
+
+	int
+getdiffcmd(finfile, delimiter, foutfile, dc)
+	RILE *finfile;
+	FILE *foutfile;
+	int delimiter;
+	struct diffcmd *dc;
+/* Get a editing command output by 'diff -n' from fin.
+ * The input is delimited by SDELIM if delimiter is set, EOF otherwise.
+ * Copy a clean version of the command to fout (if nonnull).
+ * Yield 0 for 'd', 1 for 'a', and -1 for EOF.
+ * Store the command's line number and length into dc->line1 and dc->nlines.
+ * Keep dc->adprev and dc->dafter up to date.
+ */
+{
+	register int c;
+	declarecache;
+	register FILE *fout;
+	register char *p;
+	register RILE *fin;
+	long line1, nlines, t;
+	char buf[BUFSIZ];
+
+	fin = finfile;
+	fout = foutfile;
+	setupcache(fin); cache(fin);
+	cachegeteof_(c, { if (delimiter) unexpected_EOF(); return -1; } )
+	if (delimiter) {
+		if (c==SDELIM) {
+			cacheget_(c)
+			if (c==SDELIM) {
+				buf[0] = c;
+				buf[1] = 0;
+				badDiffOutput(buf);
+			}
+			uncache(fin);
+			nextc = c;
+			if (fout)
+				aprintf(fout, "%c%c", SDELIM, c);
+			return -1;
+		}
+	}
+	p = buf;
+	do {
+		if (buf+BUFSIZ-2 <= p) {
+			rcsfaterror("diff output command line too long");
+		}
+		*p++ = c;
+		cachegeteof_(c, unexpected_EOF();)
+	} while (c != '\n');
+	uncache(fin);
+	if (delimiter)
+		++rcsline;
+	*p = '\0';
+	for (p = buf+1;  (c = *p++) == ' ';  )
+		continue;
+	line1 = 0;
+	while (isdigit(c)) {
+		if (
+			LONG_MAX/10 < line1  ||
+			(t = line1 * 10,   (line1 = t + (c - '0'))  <  t)
+		)
+			diffLineNumberTooLarge(buf);
+		c = *p++;
+	}
+	while (c == ' ')
+		c = *p++;
+	nlines = 0;
+	while (isdigit(c)) {
+		if (
+			LONG_MAX/10 < nlines  ||
+			(t = nlines * 10,   (nlines = t + (c - '0'))  <  t)
+		)
+			diffLineNumberTooLarge(buf);
+		c = *p++;
+	}
+	if (c == '\r')
+		c = *p++;
+	if (c || !nlines) {
+		badDiffOutput(buf);
+	}
+	if (line1+nlines < line1)
+		diffLineNumberTooLarge(buf);
+	switch (buf[0]) {
+	    case 'a':
+		if (line1 < dc->adprev) {
+		    rcsfaterror("backward insertion in diff output: %s", buf);
+		}
+		dc->adprev = line1 + 1;
+		break;
+	    case 'd':
+		if (line1 < dc->adprev  ||  line1 < dc->dafter) {
+		    rcsfaterror("backward deletion in diff output: %s", buf);
+		}
+		dc->adprev = line1;
+		dc->dafter = line1 + nlines;
+		break;
+	    default:
+		badDiffOutput(buf);
+	}
+	if (fout) {
+		aprintf(fout, "%s\n", buf);
+	}
+	dc->line1 = line1;
+	dc->nlines = nlines;
+	return buf[0] == 'a';
+}
+
+
+
+#ifdef SYNTEST
+
+/* Input an RCS file and print its internal data structures.  */
+
+char const cmdid[] = "syntest";
+
+	int
+main(argc,argv)
+int argc; char * argv[];
+{
+
+        if (argc<2) {
+		aputs("No input file\n",stderr);
+		exitmain(EXIT_FAILURE);
+        }
+	if (!(finptr = Iopen(argv[1], FOPEN_R, (struct stat*)0))) {
+		faterror("can't open input file %s", argv[1]);
+        }
+        Lexinit();
+        getadmin();
+	fdlock = STDOUT_FILENO;
+	putadmin();
+
+        gettree();
+
+        getdesc(true);
+
+	nextlex();
+
+	if (!eoflex()) {
+		fatserror("expecting EOF");
+        }
+	exitmain(EXIT_SUCCESS);
+}
+
+void exiterr() { _exit(EXIT_FAILURE); }
+
+#endif
diff --git a/gnu/usr.bin/rcs/lib/rcstime.c b/gnu/usr.bin/rcs/lib/rcstime.c
new file mode 100644
index 0000000000000..cfd466096ff7e
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcstime.c
@@ -0,0 +1,191 @@
+/* Convert between RCS time format and Posix and/or C formats.  */
+
+/* Copyright 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#include "rcsbase.h"
+#include "partime.h"
+#include "maketime.h"
+
+libId(rcstimeId, "$FreeBSD$")
+
+static long zone_offset; /* seconds east of UTC, or TM_LOCAL_ZONE */
+static int use_zone_offset; /* if zero, use UTC without zone indication */
+
+/*
+* Convert Unix time to RCS format.
+* For compatibility with older versions of RCS,
+* dates from 1900 through 1999 are stored without the leading "19".
+*/
+	void
+time2date(unixtime,date)
+	time_t unixtime;
+	char date[datesize];
+{
+	register struct tm const *tm = time2tm(unixtime, RCSversion<VERSION(5));
+	VOID sprintf(date,
+#		if has_printf_dot
+			"%.2d.%.2d.%.2d.%.2d.%.2d.%.2d",
+#		else
+			"%02d.%02d.%02d.%02d.%02d.%02d",
+#		endif
+		tm->tm_year  +  ((unsigned)tm->tm_year < 100 ? 0 : 1900),
+		tm->tm_mon+1, tm->tm_mday,
+		tm->tm_hour, tm->tm_min, tm->tm_sec
+	);
+}
+
+/* Like str2time, except die if an error was found.  */
+static time_t str2time_checked P((char const*,time_t,long));
+	static time_t
+str2time_checked(source, default_time, default_zone)
+	char const *source;
+	time_t default_time;
+	long default_zone;
+{
+	time_t t = str2time(source, default_time, default_zone);
+	if (t == -1)
+		faterror("unknown date/time: %s", source);
+	return t;
+}
+
+/*
+* Parse a free-format date in SOURCE, convert it
+* into RCS internal format, and store the result into TARGET.
+*/
+	void
+str2date(source, target)
+	char const *source;
+	char target[datesize];
+{
+	time2date(
+		str2time_checked(source, now(),
+			use_zone_offset ? zone_offset
+			: RCSversion<VERSION(5) ? TM_LOCAL_ZONE
+			: 0
+		),
+		target
+	);
+}
+
+/* Convert an RCS internal format date to time_t.  */
+	time_t
+date2time(source)
+	char const source[datesize];
+{
+	char s[datesize + zonelenmax];
+	return str2time_checked(date2str(source, s), (time_t)0, 0);
+}
+
+
+/* Set the time zone for date2str output.  */
+	void
+zone_set(s)
+	char const *s;
+{
+	if ((use_zone_offset = *s)) {
+		long zone;
+		char const *zonetail = parzone(s, &zone);
+		if (!zonetail || *zonetail)
+			error("%s: not a known time zone", s);
+		else
+			zone_offset = zone;
+	}
+}
+
+
+/*
+* Format a user-readable form of the RCS format DATE into the buffer DATEBUF.
+* Yield DATEBUF.
+*/
+	char const *
+date2str(date, datebuf)
+	char const date[datesize];
+	char datebuf[datesize + zonelenmax];
+{
+	register char const *p = date;
+
+	while (*p++ != '.')
+		continue;
+	if (!use_zone_offset)
+	    VOID sprintf(datebuf,
+		"19%.*s/%.2s/%.2s %.2s:%.2s:%s"
+			+ (date[2]=='.' && VERSION(5)<=RCSversion  ?  0  :  2),
+		(int)(p-date-1), date,
+		p, p+3, p+6, p+9, p+12
+	    );
+	else {
+	    struct tm t;
+	    struct tm const *z;
+	    int non_hour;
+	    long zone;
+	    char c;
+
+	    t.tm_year = atoi(date) - (date[2]=='.' ? 0 : 1900);
+	    t.tm_mon = atoi(p) - 1;
+	    t.tm_mday = atoi(p+3);
+	    t.tm_hour = atoi(p+6);
+	    t.tm_min = atoi(p+9);
+	    t.tm_sec = atoi(p+12);
+	    t.tm_wday = -1;
+	    zone = zone_offset;
+	    if (zone == TM_LOCAL_ZONE) {
+		time_t u = tm2time(&t, 0), d;
+		z = localtime(&u);
+		d = difftm(z, &t);
+		zone  =  (time_t)-1 < 0 || d < -d  ?  d  :  -(long)-d;
+	    } else {
+		adjzone(&t, zone);
+		z = &t;
+	    }
+	    c = '+';
+	    if (zone < 0) {
+		zone = -zone;
+		c = '-';
+	    }
+	    VOID sprintf(datebuf,
+#		if has_printf_dot
+		    "%.2d-%.2d-%.2d %.2d:%.2d:%.2d%c%.2d",
+#		else
+		    "%02d-%02d-%02d %02d:%02d:%02d%c%02d",
+#		endif
+		z->tm_year + 1900,
+		z->tm_mon + 1, z->tm_mday, z->tm_hour, z->tm_min, z->tm_sec,
+		c, (int) (zone / (60*60))
+	    );
+	    if ((non_hour = zone % (60*60))) {
+#		if has_printf_dot
+		    static char const fmt[] = ":%.2d";
+#		else
+		    static char const fmt[] = ":%02d";
+#		endif
+		VOID sprintf(datebuf + strlen(datebuf), fmt, non_hour / 60);
+		if ((non_hour %= 60))
+		    VOID sprintf(datebuf + strlen(datebuf), fmt, non_hour);
+	    }
+	}
+	return datebuf;
+}
diff --git a/gnu/usr.bin/rcs/lib/rcsutil.c b/gnu/usr.bin/rcs/lib/rcsutil.c
new file mode 100644
index 0000000000000..e10afff6c20d2
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/rcsutil.c
@@ -0,0 +1,1398 @@
+/* RCS utility functions */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+
+
+
+/*
+ * Revision 5.20  1995/06/16 06:19:24  eggert
+ * (catchsig): Remove `return'.
+ * Update FSF address.
+ *
+ * Revision 5.19  1995/06/02 18:19:00  eggert
+ * (catchsigaction): New name for `catchsig', for sa_sigaction signature.
+ * Use nRCS even if !has_psiginfo, to remove unused variable warning.
+ * (setup_catchsig): Use sa_sigaction only if has_sa_sigaction.
+ * Use ENOTSUP only if defined.
+ *
+ * Revision 5.18  1995/06/01 16:23:43  eggert
+ * (catchsig, restoreints, setup_catchsig): Use SA_SIGINFO, not has_psiginfo,
+ * to determine whether to use SA_SIGINFO feature,
+ * but also check at runtime whether the feature works.
+ * (catchsig): If an mmap_signal occurs, report the affected file name.
+ * (unsupported_SA_SIGINFO, accessName): New variables.
+ * (setup_catchsig): If using SA_SIGINFO, use sa_sigaction, not sa_handler.
+ * If SA_SIGINFO fails, fall back on sa_handler method.
+ *
+ * (readAccessFilenameBuffer, dupSafer, fdSafer, fopenSafer): New functions.
+ * (concatenate): Remove.
+ *
+ * (runv): Work around bad_wait_if_SIGCHLD_ignored bug.
+ * Remove reference to OPEN_O_WORK.
+ *
+ * Revision 5.17  1994/03/20 04:52:58  eggert
+ * Specify subprocess input via file descriptor, not file name.
+ * Avoid messing with I/O buffers in the child process.
+ * Define dup in terms of F_DUPFD if it exists.
+ * Move setmtime to rcsedit.c.  Remove lint.
+ *
+ * Revision 5.16  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.
+ *
+ * Revision 5.15  1993/11/03 17:42:27  eggert
+ * Use psiginfo and setreuid if available.  Move date2str to maketime.c.
+ *
+ * Revision 5.14  1992/07/28  16:12:44  eggert
+ * Add -V.  has_sigaction overrides sig_zaps_handler.  Fix -M bug.
+ * Add mmap_signal, which minimizes signal handling for non-mmap hosts.
+ *
+ * Revision 5.13  1992/02/17  23:02:28  eggert
+ * Work around NFS mmap SIGBUS problem.  Add -T support.
+ *
+ * Revision 5.12  1992/01/24  18:44:19  eggert
+ * Work around NFS mmap bug that leads to SIGBUS core dumps.  lint -> RCS_lint
+ *
+ * Revision 5.11  1992/01/06  02:42:34  eggert
+ * O_BINARY -> OPEN_O_WORK
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.10  1991/10/07  17:32:46  eggert
+ * Support piece tables even if !has_mmap.
+ *
+ * Revision 5.9  1991/08/19  03:13:55  eggert
+ * Add spawn() support.  Explicate assumptions about getting invoker's name.
+ * Standardize user-visible dates.  Tune.
+ *
+ * Revision 5.8  1991/04/21  11:58:30  eggert
+ * Plug setuid security hole.
+ *
+ * Revision 5.6  1991/02/26  17:48:39  eggert
+ * Fix setuid bug.  Use fread, fwrite more portably.
+ * Support waitpid.  Don't assume -1 is acceptable to W* macros.
+ * strsave -> str_save (DG/UX name clash)
+ *
+ * Revision 5.5  1990/12/04  05:18:49  eggert
+ * Don't output a blank line after a signal diagnostic.
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.4  1990/11/01  05:03:53  eggert
+ * Remove unneeded setid check.  Add awrite(), fremember().
+ *
+ * Revision 5.3  1990/10/06  00:16:45  eggert
+ * Don't fread F if feof(F).
+ *
+ * Revision 5.2  1990/09/04  08:02:31  eggert
+ * Store fread()'s result in an fread_type object.
+ *
+ * Revision 5.1  1990/08/29  07:14:07  eggert
+ * Declare getpwuid() more carefully.
+ *
+ * Revision 5.0  1990/08/22  08:13:46  eggert
+ * Add setuid support.  Permit multiple locks per user.
+ * Remove compile-time limits; use malloc instead.
+ * Switch to GMT.  Permit dates past 1999/12/31.
+ * Add -V.  Remove snooping.  Ansify and Posixate.
+ * Tune.  Some USG hosts define NSIG but not sys_siglist.
+ * Don't run /bin/sh if it's hopeless.
+ * Don't leave garbage behind if the output is an empty pipe.
+ * Clean up after SIGXCPU or SIGXFSZ.  Print name of signal that caused cleanup.
+ *
+ * Revision 4.6  89/05/01  15:13:40  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.5  88/11/08  16:01:02  narten
+ * corrected use of varargs routines
+ *
+ * Revision 4.4  88/08/09  19:13:24  eggert
+ * Check for memory exhaustion.
+ * Permit signal handlers to yield either 'void' or 'int'; fix oldSIGINT botch.
+ * Use execv(), not system(); yield exit status like diff(1)'s.
+ *
+ * Revision 4.3  87/10/18  10:40:22  narten
+ * Updating version numbers. Changes relative to 1.1 actually
+ * relative to 4.1
+ *
+ * Revision 1.3  87/09/24  14:01:01  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:43  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/10  15:53:13  wft
+ * Added getcaller() and findlock().
+ * Changed catchints() to check SIGINT for SIG_IGN before setting up the signal
+ * (needed for background jobs in older shells). Added restoreints().
+ * Removed printing of full RCS path from logcommand().
+ *
+ * Revision 3.8  83/02/15  15:41:49  wft
+ * Added routine fastcopy() to copy remainder of a file in blocks.
+ *
+ * Revision 3.7  82/12/24  15:25:19  wft
+ * added catchints(), ignoreints() for catching and ingnoring interrupts;
+ * fixed catchsig().
+ *
+ * Revision 3.6  82/12/08  21:52:05  wft
+ * Using DATEFORM to format dates.
+ *
+ * Revision 3.5  82/12/04  18:20:49  wft
+ * Replaced SNOOPDIR with SNOOPFILE; changed addlock() to update
+ * lockedby-field.
+ *
+ * Revision 3.4  82/12/03  17:17:43  wft
+ * Added check to addlock() ensuring only one lock per person.
+ * Addlock also returns a pointer to the lock created. Deleted fancydate().
+ *
+ * Revision 3.3  82/11/27  12:24:37  wft
+ * moved rmsema(), trysema(), trydiraccess(), getfullRCSname() to rcsfnms.c.
+ * Introduced macro SNOOP so that snoop can be placed in directory other than
+ * TARGETDIR. Changed %02d to %.2d for compatibility reasons.
+ *
+ * Revision 3.2  82/10/18  21:15:11  wft
+ * added function getfullRCSname().
+ *
+ * Revision 3.1  82/10/13  16:17:37  wft
+ * Cleanup message is now suppressed in quiet mode.
+ */
+
+
+
+
+#include "rcsbase.h"
+
+libId(utilId, "$FreeBSD$")
+
+#if !has_memcmp
+	int
+memcmp(s1, s2, n)
+	void const *s1, *s2;
+	size_t n;
+{
+	register unsigned char const
+		*p1 = (unsigned char const*)s1,
+		*p2 = (unsigned char const*)s2;
+	register size_t i = n;
+	register int r = 0;
+	while (i--  &&  !(r = (*p1++ - *p2++)))
+		;
+	return r;
+}
+#endif
+
+#if !has_memcpy
+	void *
+memcpy(s1, s2, n)
+	void *s1;
+	void const *s2;
+	size_t n;
+{
+	register char *p1 = (char*)s1;
+	register char const *p2 = (char const*)s2;
+	while (n--)
+		*p1++ = *p2++;
+	return s1;
+}
+#endif
+
+#if RCS_lint
+	malloc_type lintalloc;
+#endif
+
+/*
+ * list of blocks allocated with ftestalloc()
+ * These blocks can be freed by ffree when we're done with the current file.
+ * We could put the free block inside struct alloclist, rather than a pointer
+ * to the free block, but that would be less portable.
+ */
+struct alloclist {
+	malloc_type alloc;
+	struct alloclist *nextalloc;
+};
+static struct alloclist *alloced;
+
+
+	static malloc_type okalloc P((malloc_type));
+	static malloc_type
+okalloc(p)
+	malloc_type p;
+{
+	if (!p)
+		faterror("out of memory");
+	return p;
+}
+
+	malloc_type
+testalloc(size)
+	size_t size;
+/* Allocate a block, testing that the allocation succeeded.  */
+{
+	return okalloc(malloc(size));
+}
+
+	malloc_type
+testrealloc(ptr, size)
+	malloc_type ptr;
+	size_t size;
+/* Reallocate a block, testing that the allocation succeeded.  */
+{
+	return okalloc(realloc(ptr, size));
+}
+
+	malloc_type
+fremember(ptr)
+	malloc_type ptr;
+/* Remember PTR in 'alloced' so that it can be freed later.  Yield PTR.  */
+{
+	register struct alloclist *q = talloc(struct alloclist);
+	q->nextalloc = alloced;
+	alloced = q;
+	return q->alloc = ptr;
+}
+
+	malloc_type
+ftestalloc(size)
+	size_t size;
+/* Allocate a block, putting it in 'alloced' so it can be freed later. */
+{
+	return fremember(testalloc(size));
+}
+
+	void
+ffree()
+/* Free all blocks allocated with ftestalloc().  */
+{
+	register struct alloclist *p, *q;
+	for (p = alloced;  p;  p = q) {
+		q = p->nextalloc;
+		tfree(p->alloc);
+		tfree(p);
+	}
+	alloced = 0;
+}
+
+	void
+ffree1(f)
+	register char const *f;
+/* Free the block f, which was allocated by ftestalloc.  */
+{
+	register struct alloclist *p, **a = &alloced;
+
+	while ((p = *a)->alloc  !=  f)
+		a = &p->nextalloc;
+	*a = p->nextalloc;
+	tfree(p->alloc);
+	tfree(p);
+}
+
+	char *
+str_save(s)
+	char const *s;
+/* Save s in permanently allocated storage. */
+{
+	return strcpy(tnalloc(char, strlen(s)+1), s);
+}
+
+	char *
+fstr_save(s)
+	char const *s;
+/* Save s in storage that will be deallocated when we're done with this file. */
+{
+	return strcpy(ftnalloc(char, strlen(s)+1), s);
+}
+
+	char *
+cgetenv(name)
+	char const *name;
+/* Like getenv(), but yield a copy; getenv() can overwrite old results. */
+{
+	register char *p;
+
+	return (p=getenv(name)) ? str_save(p) : p;
+}
+
+	char const *
+getusername(suspicious)
+	int suspicious;
+/* Get the caller's login name.  Trust only getwpuid if SUSPICIOUS.  */
+{
+	static char *name;
+
+	if (!name) {
+		if (
+		    /* Prefer getenv() unless suspicious; it's much faster.  */
+#		    if getlogin_is_secure
+			    (suspicious
+			    || (
+				    !(name = cgetenv("LOGNAME"))
+				&&  !(name = cgetenv("USER"))
+			    ))
+			&&  !(name = getlogin())
+#		    else
+			suspicious
+			|| (
+				!(name = cgetenv("LOGNAME"))
+			    &&  !(name = cgetenv("USER"))
+			    &&  !(name = getlogin())
+			)
+#		    endif
+		) {
+#if has_getuid && has_getpwuid
+			struct passwd const *pw = getpwuid(ruid());
+			if (!pw)
+			    faterror("no password entry for userid %lu",
+				     (unsigned long)ruid()
+			    );
+			name = pw->pw_name;
+#else
+#if has_setuid
+			faterror("setuid not supported");
+#else
+			faterror("Who are you?  Please setenv LOGNAME.");
+#endif
+#endif
+		}
+		checksid(name);
+	}
+	return name;
+}
+
+
+
+
+#if has_signal
+
+/*
+ *	 Signal handling
+ *
+ * Standard C places too many restrictions on signal handlers.
+ * We obey as many of them as we can.
+ * Posix places fewer restrictions, and we are Posix-compatible here.
+ */
+
+static sig_atomic_t volatile heldsignal, holdlevel;
+#ifdef SA_SIGINFO
+	static int unsupported_SA_SIGINFO;
+	static siginfo_t bufsiginfo;
+	static siginfo_t *volatile heldsiginfo;
+#endif
+
+
+#if has_NFS && has_mmap && large_memory && mmap_signal
+    static char const *accessName;
+
+	  void
+    readAccessFilenameBuffer(filename, p)
+	char const *filename;
+	unsigned char const *p;
+    {
+	unsigned char volatile t;
+	accessName = filename;
+	t = *p;
+	accessName = 0;
+    }
+#else
+#   define accessName ((char const *) 0)
+#endif
+
+
+#if !has_psignal
+
+# define psignal my_psignal
+	static void my_psignal P((int,char const*));
+	static void
+my_psignal(sig, s)
+	int sig;
+	char const *s;
+{
+	char const *sname = "Unknown signal";
+#	if has_sys_siglist && defined(NSIG)
+	    if ((unsigned)sig < NSIG)
+		sname = sys_siglist[sig];
+#	else
+	    switch (sig) {
+#	       ifdef SIGHUP
+		case SIGHUP:	sname = "Hangup";  break;
+#	       endif
+#	       ifdef SIGINT
+		case SIGINT:	sname = "Interrupt";  break;
+#	       endif
+#	       ifdef SIGPIPE
+		case SIGPIPE:	sname = "Broken pipe";  break;
+#	       endif
+#	       ifdef SIGQUIT
+		case SIGQUIT:	sname = "Quit";  break;
+#	       endif
+#	       ifdef SIGTERM
+		case SIGTERM:	sname = "Terminated";  break;
+#	       endif
+#	       ifdef SIGXCPU
+		case SIGXCPU:	sname = "Cputime limit exceeded";  break;
+#	       endif
+#	       ifdef SIGXFSZ
+		case SIGXFSZ:	sname = "Filesize limit exceeded";  break;
+#	       endif
+#	      if has_mmap && large_memory
+#	       if defined(SIGBUS) && mmap_signal==SIGBUS
+		case SIGBUS:	sname = "Bus error";  break;
+#	       endif
+#	       if defined(SIGSEGV) && mmap_signal==SIGSEGV
+		case SIGSEGV:	sname = "Segmentation fault";  break;
+#	       endif
+#	      endif
+	    }
+#	endif
+
+	/* Avoid calling sprintf etc., in case they're not reentrant.  */
+	{
+	    char const *p;
+	    char buf[BUFSIZ], *b = buf;
+	    for (p = s;  *p;  *b++ = *p++)
+		continue;
+	    *b++ = ':';
+	    *b++ = ' ';
+	    for (p = sname;  *p;  *b++ = *p++)
+		continue;
+	    *b++ = '\n';
+	    VOID write(STDERR_FILENO, buf, b - buf);
+	}
+}
+#endif
+
+static signal_type catchsig P((int));
+#ifdef SA_SIGINFO
+	static signal_type catchsigaction P((int,siginfo_t*,void*));
+#endif
+
+	static signal_type
+catchsig(s)
+	int s;
+#ifdef SA_SIGINFO
+{
+	catchsigaction(s, (siginfo_t *)0, (void *)0);
+}
+	static signal_type
+catchsigaction(s, i, c)
+	int s;
+	siginfo_t *i;
+	void *c;
+#endif
+{
+#   if sig_zaps_handler
+	/* If a signal arrives before we reset the handler, we lose. */
+	VOID signal(s, SIG_IGN);
+#   endif
+
+#   ifdef SA_SIGINFO
+	if (!unsupported_SA_SIGINFO)
+	    i = 0;
+#   endif
+
+    if (holdlevel) {
+	heldsignal = s;
+#	ifdef SA_SIGINFO
+	    if (i) {
+		bufsiginfo = *i;
+		heldsiginfo = &bufsiginfo;
+	    }
+#	endif
+	return;
+    }
+
+    ignoreints();
+    setrid();
+    if (!quietflag) {
+	/* Avoid calling sprintf etc., in case they're not reentrant.  */
+	char const *p;
+	char buf[BUFSIZ], *b = buf;
+
+	if ( !	(
+#		if has_mmap && large_memory && mmap_signal
+			/* Check whether this signal was planned.  */
+			s == mmap_signal && accessName
+#		else
+			0
+#		endif
+	)) {
+	    char const *nRCS = "\nRCS";
+#	    if defined(SA_SIGINFO) && has_si_errno && has_mmap && large_memory && mmap_signal
+		if (s == mmap_signal  &&  i  &&  i->si_errno) {
+		    errno = i->si_errno;
+		    perror(nRCS++);
+		}
+#	    endif
+#	    if defined(SA_SIGINFO) && has_psiginfo
+		if (i)
+		    psiginfo(i, nRCS);
+		else
+		    psignal(s, nRCS);
+#	    else
+		psignal(s, nRCS);
+#	    endif
+	}
+
+	for (p = "RCS: ";  *p;  *b++ = *p++)
+	    continue;
+#	if has_mmap && large_memory && mmap_signal
+	    if (s == mmap_signal) {
+		p = accessName;
+		if (!p)
+		    p = "Was a file changed by some other process?  ";
+		else {
+		    char const *p1;
+		    for (p1 = p;  *p1;  p1++)
+			continue;
+		    VOID write(STDERR_FILENO, buf, b - buf);
+		    VOID write(STDERR_FILENO, p, p1 - p);
+		    b = buf;
+		    p = ": Permission denied.  ";
+		}
+		while (*p)
+		    *b++ = *p++;
+	    }
+#	endif
+	for (p = "Cleaning up.\n";  *p;  *b++ = *p++)
+	    continue;
+	VOID write(STDERR_FILENO, buf, b - buf);
+    }
+    exiterr();
+}
+
+	void
+ignoreints()
+{
+	++holdlevel;
+}
+
+	void
+restoreints()
+{
+	if (!--holdlevel && heldsignal)
+#	    ifdef SA_SIGINFO
+		VOID catchsigaction(heldsignal, heldsiginfo, (void *)0);
+#	    else
+		VOID catchsig(heldsignal);
+#	    endif
+}
+
+
+static void setup_catchsig P((int const*,int));
+
+#if has_sigaction
+
+	static void check_sig P((int));
+	static void
+  check_sig(r)
+	int r;
+  {
+	if (r != 0)
+		efaterror("signal handling");
+  }
+
+	static void
+  setup_catchsig(sig, sigs)
+	int const *sig;
+	int sigs;
+  {
+	register int i, j;
+	struct sigaction act;
+
+	for (i=sigs; 0<=--i; ) {
+	    check_sig(sigaction(sig[i], (struct sigaction*)0, &act));
+	    if (act.sa_handler != SIG_IGN) {
+		act.sa_handler = catchsig;
+#		ifdef SA_SIGINFO
+		    if (!unsupported_SA_SIGINFO) {
+#			if has_sa_sigaction
+			    act.sa_sigaction = catchsigaction;
+#			else
+			    act.sa_handler = catchsigaction;
+#			endif
+			act.sa_flags |= SA_SIGINFO;
+		    }
+#		endif
+		for (j=sigs; 0<=--j; )
+		    check_sig(sigaddset(&act.sa_mask, sig[j]));
+		if (sigaction(sig[i], &act, (struct sigaction*)0) != 0) {
+#		    if defined(SA_SIGINFO) && defined(ENOTSUP)
+			if (errno == ENOTSUP  &&  !unsupported_SA_SIGINFO) {
+			    /* Turn off use of SA_SIGINFO and try again.  */
+			    unsupported_SA_SIGINFO = 1;
+			    i++;
+			    continue;
+			}
+#		    endif
+		    check_sig(-1);
+		}
+	    }
+	}
+  }
+
+#else
+#if has_sigblock
+
+	static void
+  setup_catchsig(sig, sigs)
+	int const *sig;
+	int sigs;
+  {
+	register int i;
+	int mask;
+
+	mask = 0;
+	for (i=sigs; 0<=--i; )
+		mask |= sigmask(sig[i]);
+	mask = sigblock(mask);
+	for (i=sigs; 0<=--i; )
+		if (
+		    signal(sig[i], catchsig) == SIG_IGN  &&
+		    signal(sig[i], SIG_IGN) != catchsig
+		)
+			faterror("signal catcher failure");
+	VOID sigsetmask(mask);
+  }
+
+#else
+
+	static void
+  setup_catchsig(sig, sigs)
+	int const *sig;
+	int sigs;
+  {
+	register i;
+
+	for (i=sigs; 0<=--i; )
+		if (
+		    signal(sig[i], SIG_IGN) != SIG_IGN  &&
+		    signal(sig[i], catchsig) != SIG_IGN
+		)
+			faterror("signal catcher failure");
+  }
+
+#endif
+#endif
+
+
+static int const regsigs[] = {
+# ifdef SIGHUP
+	SIGHUP,
+# endif
+# ifdef SIGINT
+	SIGINT,
+# endif
+# ifdef SIGPIPE
+	SIGPIPE,
+# endif
+# ifdef SIGQUIT
+	SIGQUIT,
+# endif
+# ifdef SIGTERM
+	SIGTERM,
+# endif
+# ifdef SIGXCPU
+	SIGXCPU,
+# endif
+# ifdef SIGXFSZ
+	SIGXFSZ,
+# endif
+};
+
+	void
+catchints()
+{
+	static int catching_ints;
+	if (!catching_ints) {
+	    catching_ints = true;
+	    setup_catchsig(regsigs, (int) (sizeof(regsigs)/sizeof(*regsigs)));
+	}
+}
+
+#if has_mmap && large_memory && mmap_signal
+
+    /*
+    * If you mmap an NFS file, and someone on another client removes the last
+    * link to that file, and you later reference an uncached part of that file,
+    * you'll get a SIGBUS or SIGSEGV (depending on the operating system).
+    * Catch the signal and report the problem to the user.
+    * Unfortunately, there's no portable way to differentiate between this
+    * problem and actual bugs in the program.
+    * This NFS problem is rare, thank goodness.
+    *
+    * This can also occur if someone truncates the file, even without NFS.
+    */
+
+    static int const mmapsigs[] = { mmap_signal };
+
+	    void
+    catchmmapints()
+    {
+	static int catching_mmap_ints;
+	if (!catching_mmap_ints) {
+	    catching_mmap_ints = true;
+	    setup_catchsig(mmapsigs, (int)(sizeof(mmapsigs)/sizeof(*mmapsigs)));
+	}
+    }
+#endif
+
+#endif /* has_signal */
+
+
+	void
+fastcopy(inf,outf)
+	register RILE *inf;
+	FILE *outf;
+/* Function: copies the remainder of file inf to outf.
+ */
+{
+#if large_memory
+#	if maps_memory
+	    awrite((char const*)inf->ptr, (size_t)(inf->lim - inf->ptr), outf);
+	    inf->ptr = inf->lim;
+#	else
+	    for (;;) {
+		awrite((char const*)inf->ptr, (size_t)(inf->readlim - inf->ptr), outf);
+		inf->ptr = inf->readlim;
+		if (inf->ptr == inf->lim)
+		    break;
+		VOID Igetmore(inf);
+	    }
+#	endif
+#else
+	char buf[BUFSIZ*8];
+	register fread_type rcount;
+
+        /*now read the rest of the file in blocks*/
+	while (!feof(inf)) {
+		if (!(rcount = Fread(buf,sizeof(*buf),sizeof(buf),inf))) {
+			testIerror(inf);
+			return;
+		}
+		awrite(buf, (size_t)rcount, outf);
+        }
+#endif
+}
+
+#ifndef SSIZE_MAX
+ /* This does not work in #ifs, but it's good enough for us.  */
+ /* Underestimating SSIZE_MAX may slow us down, but it won't break us.  */
+#	define SSIZE_MAX ((unsigned)-1 >> 1)
+#endif
+
+	void
+awrite(buf, chars, f)
+	char const *buf;
+	size_t chars;
+	FILE *f;
+{
+	/* Posix 1003.1-1990 ssize_t hack */
+	while (SSIZE_MAX < chars) {
+		if (Fwrite(buf, sizeof(*buf), SSIZE_MAX, f)  !=  SSIZE_MAX)
+			Oerror();
+		buf += SSIZE_MAX;
+		chars -= SSIZE_MAX;
+	}
+
+	if (Fwrite(buf, sizeof(*buf), chars, f)  !=  chars)
+		Oerror();
+}
+
+/* dup a file descriptor; the result must not be stdin, stdout, or stderr.  */
+	static int dupSafer P((int));
+	static int
+dupSafer(fd)
+	int fd;
+{
+#	ifdef F_DUPFD
+	    return fcntl(fd, F_DUPFD, STDERR_FILENO + 1);
+#	else
+	    int e, f, i, used = 0;
+	    while (STDIN_FILENO <= (f = dup(fd))  &&  f <= STDERR_FILENO)
+		    used |= 1<<f;
+	    e = errno;
+	    for (i = STDIN_FILENO;  i <= STDERR_FILENO;  i++)
+		    if (used & (1<<i))
+			    VOID close(i);
+	    errno = e;
+	    return f;
+#	endif
+}
+
+/* Renumber a file descriptor so that it's not stdin, stdout, or stderr.  */
+	int
+fdSafer(fd)
+	int fd;
+{
+	if (STDIN_FILENO <= fd  &&  fd <= STDERR_FILENO) {
+		int f = dupSafer(fd);
+		int e = errno;
+		VOID close(fd);
+		errno = e;
+		fd = f;
+	}
+	return fd;
+}
+
+/* Like fopen, except the result is never stdin, stdout, or stderr.  */
+	FILE *
+fopenSafer(filename, type)
+	char const *filename;
+	char const *type;
+{
+	FILE *stream = fopen(filename, type);
+	if (stream) {
+		int fd = fileno(stream);
+		if (STDIN_FILENO <= fd  &&  fd <= STDERR_FILENO) {
+			int f = dupSafer(fd);
+			if (f < 0) {
+				int e = errno;
+				VOID fclose(stream);
+				errno = e;
+				return 0;
+			}
+			if (fclose(stream) != 0) {
+				int e = errno;
+				VOID close(f);
+				errno = e;
+				return 0;
+			}
+			stream = fdopen(f, type);
+		}
+	}
+	return stream;
+}
+
+
+#ifdef F_DUPFD
+#	undef dup
+#	define dup(fd) fcntl(fd, F_DUPFD, 0)
+#endif
+
+
+#if has_fork || has_spawn
+
+	static int movefd P((int,int));
+	static int
+movefd(old, new)
+	int old, new;
+{
+	if (old < 0  ||  old == new)
+		return old;
+#	ifdef F_DUPFD
+		new = fcntl(old, F_DUPFD, new);
+#	else
+		new = dup2(old, new);
+#	endif
+	return close(old)==0 ? new : -1;
+}
+
+	static int fdreopen P((int,char const*,int));
+	static int
+fdreopen(fd, file, flags)
+	int fd;
+	char const *file;
+	int flags;
+{
+	int newfd;
+	VOID close(fd);
+	newfd =
+#if !open_can_creat
+		flags&O_CREAT ? creat(file, S_IRUSR|S_IWUSR) :
+#endif
+		open(file, flags, S_IRUSR|S_IWUSR);
+	return movefd(newfd, fd);
+}
+
+#if has_spawn
+	static void redirect P((int,int));
+	static void
+redirect(old, new)
+	int old, new;
+/*
+* Move file descriptor OLD to NEW.
+* If OLD is -1, do nothing.
+* If OLD is -2, just close NEW.
+*/
+{
+	if ((old != -1 && close(new) != 0) || (0 <= old && movefd(old,new) < 0))
+		efaterror("spawn I/O redirection");
+}
+#endif
+
+
+#else /* !has_fork && !has_spawn */
+
+	static void bufargcat P((struct buf*,int,char const*));
+	static void
+bufargcat(b, c, s)
+	register struct buf *b;
+	int c;
+	register char const *s;
+/* Append to B a copy of C, plus a quoted copy of S.  */
+{
+	register char *p;
+	register char const *t;
+	size_t bl, sl;
+
+	for (t=s, sl=0;  *t;  )
+		sl  +=  3*(*t++=='\'') + 1;
+	bl = strlen(b->string);
+	bufrealloc(b, bl + sl + 4);
+	p = b->string + bl;
+	*p++ = c;
+	*p++ = '\'';
+	while (*s) {
+		if (*s == '\'') {
+			*p++ = '\'';
+			*p++ = '\\';
+			*p++ = '\'';
+		}
+		*p++ = *s++;
+	}
+	*p++ = '\'';
+	*p = 0;
+}
+
+#endif
+
+#if !has_spawn && has_fork
+/*
+* Output the string S to stderr, without touching any I/O buffers.
+* This is useful if you are a child process, whose buffers are usually wrong.
+* Exit immediately if the write does not completely succeed.
+*/
+static void write_stderr P((char const *));
+	static void
+write_stderr(s)
+	char const *s;
+{
+	size_t slen = strlen(s);
+	if (write(STDERR_FILENO, s, slen) != slen)
+		_exit(EXIT_TROUBLE);
+}
+#endif
+
+/*
+* Run a command.
+* infd, if not -1, is the input file descriptor.
+* outname, if nonzero, is the name of the output file.
+* args[1..] form the command to be run; args[0] might be modified.
+*/
+	int
+runv(infd, outname, args)
+	int infd;
+	char const *outname, **args;
+{
+	int wstatus;
+
+#if bad_wait_if_SIGCHLD_ignored
+	static int fixed_SIGCHLD;
+	if (!fixed_SIGCHLD) {
+	    fixed_SIGCHLD = true;
+#	    ifndef SIGCHLD
+#	    define SIGCHLD SIGCLD
+#	    endif
+	    VOID signal(SIGCHLD, SIG_DFL);
+	}
+#endif
+
+	oflush();
+	eflush();
+    {
+#if has_spawn
+	int in, out;
+	char const *file;
+
+	in = -1;
+	if (infd != -1  &&  infd != STDIN_FILENO) {
+	    if ((in = dup(STDIN_FILENO)) < 0) {
+		if (errno != EBADF)
+		    efaterror("spawn input setup");
+		in = -2;
+	    } else {
+#		ifdef F_DUPFD
+		    if (close(STDIN_FILENO) != 0)
+			efaterror("spawn input close");
+#		endif
+	    }
+	    if (
+#		ifdef F_DUPFD
+		    fcntl(infd, F_DUPFD, STDIN_FILENO) != STDIN_FILENO
+#		else
+		    dup2(infd, STDIN_FILENO) != STDIN_FILENO
+#		endif
+	    )
+		efaterror("spawn input redirection");
+	}
+
+	out = -1;
+	if (outname) {
+	    if ((out = dup(STDOUT_FILENO)) < 0) {
+		if (errno != EBADF)
+		    efaterror("spawn output setup");
+		out = -2;
+	    }
+	    if (fdreopen(
+		STDOUT_FILENO, outname,
+		O_CREAT | O_TRUNC | O_WRONLY
+	    ) < 0)
+		efaterror(outname);
+	}
+
+	wstatus = spawn_RCS(0, args[1], (char**)(args + 1));
+#	ifdef RCS_SHELL
+	    if (wstatus == -1  &&  errno == ENOEXEC) {
+		args[0] = RCS_SHELL;
+		wstatus = spawnv(0, args[0], (char**)args);
+	    }
+#	endif
+	redirect(in, STDIN_FILENO);
+	redirect(out, STDOUT_FILENO);
+#else
+#if has_fork
+	pid_t pid;
+	if (!(pid = vfork())) {
+		char const *notfound;
+		if (infd != -1  &&  infd != STDIN_FILENO  &&  (
+#		    ifdef F_DUPFD
+			(VOID close(STDIN_FILENO),
+			fcntl(infd, F_DUPFD, STDIN_FILENO) != STDIN_FILENO)
+#		    else
+			dup2(infd, STDIN_FILENO) != STDIN_FILENO
+#		    endif
+		)) {
+		    /* Avoid perror since it may misuse buffers.  */
+		    write_stderr(args[1]);
+		    write_stderr(": I/O redirection failed\n");
+		    _exit(EXIT_TROUBLE);
+		}
+
+		if (outname)
+		    if (fdreopen(
+			STDOUT_FILENO, outname,
+			O_CREAT | O_TRUNC | O_WRONLY
+		    ) < 0) {
+			/* Avoid perror since it may misuse buffers.  */
+			write_stderr(args[1]);
+			write_stderr(": ");
+			write_stderr(outname);
+			write_stderr(": cannot create\n");
+			_exit(EXIT_TROUBLE);
+		    }
+		VOID exec_RCS(args[1], (char**)(args + 1));
+		notfound = args[1];
+#		ifdef RCS_SHELL
+		    if (errno == ENOEXEC) {
+			args[0] = notfound = RCS_SHELL;
+			VOID execv(args[0], (char**)args);
+		    }
+#		endif
+
+		/* Avoid perror since it may misuse buffers.  */
+		write_stderr(notfound);
+		write_stderr(": not found\n");
+		_exit(EXIT_TROUBLE);
+	}
+	if (pid < 0)
+		efaterror("fork");
+#	if has_waitpid
+		if (waitpid(pid, &wstatus, 0) < 0)
+			efaterror("waitpid");
+#	else
+		{
+			pid_t w;
+			do {
+				if ((w = wait(&wstatus)) < 0)
+					efaterror("wait");
+			} while (w != pid);
+		}
+#	endif
+#else
+	static struct buf b;
+	char const *p;
+
+	/* Use system().  On many hosts system() discards signals.  Yuck!  */
+	p = args + 1;
+	bufscpy(&b, *p);
+	while (*++p)
+		bufargcat(&b, ' ', *p);
+	if (infd != -1  &&  infd != STDIN_FILENO) {
+		char redirection[32];
+		VOID sprintf(redirection, "<&%d", infd);
+		bufscat(&b, redirection);
+	}
+	if (outname)
+		bufargcat(&b, '>', outname);
+	wstatus = system(b.string);
+#endif
+#endif
+    }
+	if (!WIFEXITED(wstatus)) {
+		if (WIFSIGNALED(wstatus)) {
+			psignal(WTERMSIG(wstatus), args[1]);
+			fatcleanup(1);
+		}
+		faterror("%s failed for unknown reason", args[1]);
+	}
+	return WEXITSTATUS(wstatus);
+}
+
+#define CARGSMAX 20
+/*
+* Run a command.
+* infd, if not -1, is the input file descriptor.
+* outname, if nonzero, is the name of the output file.
+* The remaining arguments specify the command and its arguments.
+*/
+	int
+#if has_prototypes
+run(int infd, char const *outname, ...)
+#else
+	/*VARARGS2*/
+run(infd, outname, va_alist)
+	int infd;
+	char const *outname;
+	va_dcl
+#endif
+{
+	va_list ap;
+	char const *rgargs[CARGSMAX];
+	register int i;
+	vararg_start(ap, outname);
+	for (i = 1;  (rgargs[i++] = va_arg(ap, char const*));  )
+		if (CARGSMAX <= i)
+			faterror("too many command arguments");
+	va_end(ap);
+	return runv(infd, outname, rgargs);
+}
+
+
+int RCSversion;
+
+	void
+setRCSversion(str)
+	char const *str;
+{
+	static int oldversion;
+
+	register char const *s = str + 2;
+
+	if (*s) {
+		int v = VERSION_DEFAULT;
+
+		if (oldversion)
+			redefined('V');
+		oldversion = true;
+		v = 0;
+		while (isdigit(*s))
+			v  =  10*v + *s++ - '0';
+		if (*s)
+			error("%s isn't a number", str);
+		else if (v < VERSION_min  ||  VERSION_max < v)
+			error("%s out of range %d..%d",
+				str, VERSION_min, VERSION_max
+			);
+
+		RCSversion = VERSION(v);
+	} else {
+		printf("RCS version %s\n", RCS_version_string);
+		exit(0);
+	}
+}
+
+	int
+getRCSINIT(argc, argv, newargv)
+	int argc;
+	char **argv, ***newargv;
+{
+	register char *p, *q, **pp;
+	char const *ev;
+	size_t n;
+
+	if ((ev = cgetenv("RCSLOCALID")))
+		setRCSLocalId(ev);
+
+	if ((ev = cgetenv("RCSINCEXC")))
+		setIncExc(ev);
+
+	if (!(q = cgetenv("RCSINIT")))
+		*newargv = argv;
+	else {
+		n = argc + 2;
+		/*
+		 * Count spaces in RCSINIT to allocate a new arg vector.
+		 * This is an upper bound, but it's OK even if too large.
+		 */
+		for (p = q;  ;  ) {
+			switch (*p++) {
+			    default:
+				continue;
+
+			    case ' ':
+			    case '\b': case '\f': case '\n':
+			    case '\r': case '\t': case '\v':
+				n++;
+				continue;
+
+			    case '\0':
+				break;
+			}
+			break;
+		}
+		*newargv = pp = tnalloc(char*, n);
+		*pp++ = *argv++; /* copy program name */
+		for (p = q;  ;  ) {
+			for (;;) {
+				switch (*q) {
+				    case '\0':
+					goto copyrest;
+
+				    case ' ':
+				    case '\b': case '\f': case '\n':
+				    case '\r': case '\t': case '\v':
+					q++;
+					continue;
+				}
+				break;
+			}
+			*pp++ = p;
+			++argc;
+			for (;;) {
+				switch ((*p++ = *q++)) {
+				    case '\0':
+					goto copyrest;
+
+				    case '\\':
+					if (!*q)
+						goto copyrest;
+					p[-1] = *q++;
+					continue;
+
+				    default:
+					continue;
+
+				    case ' ':
+				    case '\b': case '\f': case '\n':
+				    case '\r': case '\t': case '\v':
+					break;
+				}
+				break;
+			}
+			p[-1] = '\0';
+		}
+	    copyrest:
+		while ((*pp++ = *argv++))
+			continue;
+	}
+	return argc;
+}
+
+
+#define cacheid(E) static uid_t i; static int s; if (!s){ s=1; i=(E); } return i
+
+#if has_getuid
+	uid_t ruid() { cacheid(getuid()); }
+#endif
+#if has_setuid
+	uid_t euid() { cacheid(geteuid()); }
+#endif
+
+
+#if has_setuid
+
+/*
+ * Setuid execution really works only with Posix 1003.1a Draft 5 seteuid(),
+ * because it lets us switch back and forth between arbitrary users.
+ * If seteuid() doesn't work, we fall back on setuid(),
+ * which works if saved setuid is supported,
+ * unless the real or effective user is root.
+ * This area is such a mess that we always check switches at runtime.
+ */
+
+	static void
+#if has_prototypes
+set_uid_to(uid_t u)
+#else
+ set_uid_to(u) uid_t u;
+#endif
+/* Become user u.  */
+{
+	static int looping;
+
+	if (euid() == ruid())
+		return;
+#if (has_fork||has_spawn) && DIFF_ABSOLUTE
+#	if has_setreuid
+		if (setreuid(u==euid() ? ruid() : euid(), u) != 0)
+			efaterror("setuid");
+#	else
+		if (seteuid(u) != 0)
+			efaterror("setuid");
+#	endif
+#endif
+	if (geteuid() != u) {
+		if (looping)
+			return;
+		looping = true;
+		faterror("root setuid not supported" + (u?5:0));
+	}
+}
+
+static int stick_with_euid;
+
+	void
+/* Ignore all calls to seteid() and setrid().  */
+nosetid()
+{
+	stick_with_euid = true;
+}
+
+	void
+seteid()
+/* Become effective user.  */
+{
+	if (!stick_with_euid)
+		set_uid_to(euid());
+}
+
+	void
+setrid()
+/* Become real user.  */
+{
+	if (!stick_with_euid)
+		set_uid_to(ruid());
+}
+#endif
+
+	time_t
+now()
+{
+	static time_t t;
+	if (!t  &&  time(&t) == -1)
+		efaterror("time");
+	return t;
+}
diff --git a/gnu/usr.bin/rcs/lib/version.c b/gnu/usr.bin/rcs/lib/version.c
new file mode 100644
index 0000000000000..81f5585b9d1d0
--- /dev/null
+++ b/gnu/usr.bin/rcs/lib/version.c
@@ -0,0 +1,2 @@
+#include "rcsbase.h"
+char const RCS_version_string[] = "5.7";
diff --git a/gnu/usr.bin/rcs/merge/Makefile b/gnu/usr.bin/rcs/merge/Makefile
new file mode 100644
index 0000000000000..9022bc4bf6e5b
--- /dev/null
+++ b/gnu/usr.bin/rcs/merge/Makefile
@@ -0,0 +1,8 @@
+PROG=	merge
+SRCS=	merge.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=  ${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/merge/merge.1 b/gnu/usr.bin/rcs/merge/merge.1
new file mode 100644
index 0000000000000..a4fd35b7986aa
--- /dev/null
+++ b/gnu/usr.bin/rcs/merge/merge.1
@@ -0,0 +1,137 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.TH MERGE 1 \*(Dt GNU
+.SH NAME
+merge \- three-way file merge
+.SH SYNOPSIS
+.B merge
+[
+.I "options"
+]
+.I "file1 file2 file3"
+.SH DESCRIPTION
+.B merge
+incorporates all changes that lead from
+.I file2
+to
+.I file3
+into
+.IR file1 .
+The result ordinarily goes into
+.IR file1 .
+.B merge
+is useful for combining separate changes to an original.  Suppose
+.I file2
+is the original, and both
+.I file1
+and
+.I file3
+are modifications of
+.IR file2 .
+Then
+.B merge
+combines both changes.
+.PP
+A conflict occurs if both
+.I file1
+and
+.I file3
+have changes in a common segment of lines.
+If a conflict is found,
+.B merge
+normally outputs a warning and brackets the conflict with
+.B <<<<<<<
+and
+.B >>>>>>>
+lines.
+A typical conflict will look like this:
+.LP
+.RS
+.nf
+.BI <<<<<<< " file A"
+.I "lines in file A"
+.B "======="
+.I "lines in file B"
+.BI >>>>>>> " file B"
+.RE
+.fi
+.LP
+If there are conflicts, the user should edit the result and delete one of the
+alternatives.
+.SH OPTIONS
+.TP
+.B \-A
+Output conflicts using the
+.B \-A
+style of
+.BR diff3 (1),
+if supported by
+.BR diff3 .
+This merges all changes leading from
+.I file2
+to
+.I file3
+into
+.IR file1 ,
+and generates the most verbose output.
+.TP
+\f3\-E\fP, \f3\-e\fP
+These options specify conflict styles that generate less information
+than
+.BR \-A .
+See
+.BR diff3 (1)
+for details.
+The default is
+.BR \-E .
+With
+.BR \-e ,
+.B merge
+does not warn about conflicts.
+.TP
+.BI \-L " label"
+This option may be given up to three times, and specifies labels
+to be used in place of the corresponding file names in conflict reports.
+That is,
+.B "merge\ \-L\ x\ \-L\ y\ \-L\ z\ a\ b\ c"
+generates output that looks like it came from files
+.BR x ,
+.B y
+and
+.B z
+instead of from files
+.BR a ,
+.B b
+and
+.BR c .
+.TP
+.BI \-p
+Send results to standard output instead of overwriting
+.IR file1 .
+.TP
+.BI \-q
+Quiet; do not warn about conflicts.
+.TP
+.BI \-V
+Print \*r's version number.
+.SH DIAGNOSTICS
+Exit status is 0 for no conflicts, 1 for some conflicts, 2 for trouble.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH SEE ALSO
+diff3(1), diff(1), rcsmerge(1), co(1).
+.SH BUGS
+It normally does not make sense to merge binary files as if they were text, but
+.B merge
+tries to do it anyway.
+.br
diff --git a/gnu/usr.bin/rcs/merge/merge.c b/gnu/usr.bin/rcs/merge/merge.c
new file mode 100644
index 0000000000000..aa127bf1c8ec8
--- /dev/null
+++ b/gnu/usr.bin/rcs/merge/merge.c
@@ -0,0 +1,113 @@
+/* merge - three-way file merge */
+
+/* Copyright 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+#include "rcsbase.h"
+
+static void badoption P((char const*));
+
+static char const usage[] =
+ "\nmerge: usage: merge [-AeEpqxX3] [-L lab [-L lab [-L lab]]] file1 file2 file3";
+
+	static void
+badoption(a)
+	char const *a;
+{
+	error("unknown option: %s%s", a, usage);
+}
+
+
+mainProg(mergeId, "merge", "$FreeBSD$")
+{
+	register char const *a;
+	char const *arg[3], *label[3], *edarg = 0;
+	int labels, tostdout;
+
+	labels = 0;
+	tostdout = false;
+
+	for (;  (a = *++argv)  &&  *a++ == '-';  --argc) {
+		switch (*a++) {
+			case 'A': case 'E': case 'e':
+				if (edarg  &&  edarg[1] != (*argv)[1])
+					error("%s and %s are incompatible",
+						edarg, *argv
+					);
+				edarg = *argv;
+				break;
+
+			case 'p': tostdout = true; break;
+			case 'q': quietflag = true; break;
+
+			case 'L':
+				if (3 <= labels)
+					faterror("too many -L options");
+				if (!(label[labels++] = *++argv))
+					faterror("-L needs following argument");
+				--argc;
+				break;
+
+			case 'V':
+				printf("RCS version %s\n", RCS_version_string);
+				exitmain(0);
+
+			default:
+				badoption(a - 2);
+				continue;
+		}
+		if (*a)
+			badoption(a - 2);
+	}
+
+	if (argc != 4)
+		faterror("%s arguments%s",
+			argc<4 ? "not enough" : "too many",  usage
+		);
+
+	/* This copy keeps us `const'-clean.  */
+	arg[0] = argv[0];
+	arg[1] = argv[1];
+	arg[2] = argv[2];
+
+	for (;  labels < 3;  labels++)
+		label[labels] = arg[labels];
+
+	if (nerror)
+		exiterr();
+	exitmain(merge(tostdout, edarg, label, arg));
+}
+
+
+#if RCS_lint
+#	define exiterr mergeExit
+#endif
+	void
+exiterr()
+{
+	tempunlink();
+	_exit(DIFF_TROUBLE);
+}
diff --git a/gnu/usr.bin/rcs/rcs/Makefile b/gnu/usr.bin/rcs/rcs/Makefile
new file mode 100644
index 0000000000000..aa7cc5fb315d2
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcs/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+PROG=	rcs
+MAN=	rcs.1 rcsintro.1 rcsfile.5
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=  ${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rcs/rcs.1 b/gnu/usr.bin/rcs/rcs/rcs.1
new file mode 100644
index 0000000000000..37fb59fea0684
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcs/rcs.1
@@ -0,0 +1,454 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.if !\n(.g \{\
+.	if !\w|\*(lq| \{\
+.		ds lq ``
+.		if \w'\(lq' .ds lq "\(lq
+.	\}
+.	if !\w|\*(rq| \{\
+.		ds rq ''
+.		if \w'\(rq' .ds rq "\(rq
+.	\}
+.\}
+.TH RCS 1 \*(Dt GNU
+.SH NAME
+rcs \- change RCS file attributes
+.SH SYNOPSIS
+.B rcs
+.IR "options file " .\|.\|.
+.SH DESCRIPTION
+.B rcs
+creates new \*r files or changes attributes of existing ones.
+An \*r file contains multiple revisions of text,
+an access list, a change log,
+descriptive text,
+and some control attributes.
+For
+.B rcs
+to work, the caller's login name must be on the access list,
+except if the access list is empty, the caller is the owner of the file
+or the superuser, or
+the
+.B \-i
+option is present.
+.PP
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+Names are paired as explained in
+.BR ci (1).
+Revision numbers use the syntax described in
+.BR ci (1).
+.SH OPTIONS
+.TP
+.B \-i
+Create and initialize a new \*r file, but do not deposit any revision.
+If the \*r file has no path prefix, try to place it
+first into the subdirectory
+.BR ./RCS ,
+and then into the current directory.
+If the \*r file
+already exists, print an error message.
+.TP
+.BI \-a "logins"
+Append the login names appearing in the comma-separated list
+.I logins
+to the access list of the \*r file.
+.TP
+.BI \-A "oldfile"
+Append the access list of
+.I oldfile
+to the access list of the \*r file.
+.TP
+.BR \-e [\f2logins\fP]
+Erase the login names appearing in the comma-separated list
+.I logins
+from the access list of the \*r file.
+If
+.I logins
+is omitted, erase the entire access list.
+.TP
+.BR \-b [\f2rev\fP]
+Set the default branch to
+.IR rev .
+If
+.I rev
+is omitted, the default
+branch is reset to the (dynamically) highest branch on the trunk.
+.TP
+.BI \-c string
+Set the comment leader to
+.IR string .
+An initial
+.BR ci ,
+or an
+.B "rcs\ \-i"
+without
+.BR \-c ,
+guesses the comment leader from the suffix of the working filename.
+.RS
+.PP
+This option is obsolescent, since \*r normally uses the preceding
+.B $\&Log$
+line's prefix when inserting log lines during checkout (see
+.BR co (1)).
+However, older versions of \*r use the comment leader instead of the
+.B $\&Log$
+line's prefix, so
+if you plan to access a file with both old and new versions of \*r,
+make sure its comment leader matches its
+.B $\&Log$
+line prefix.
+.RE
+.TP
+.BI \-k subst
+Set the default keyword substitution to
+.IR subst .
+The effect of keyword substitution is described in
+.BR co (1).
+Giving an explicit
+.B \-k
+option to
+.BR co ,
+.BR rcsdiff ,
+and
+.B rcsmerge
+overrides this default.
+Beware
+.BR "rcs\ \-kv",
+because
+.B \-kv
+is incompatible with
+.BR "co\ \-l".
+Use
+.B "rcs\ \-kkv"
+to restore the normal default keyword substitution.
+.TP
+.BR \-l [\f2rev\fP]
+Lock the revision with number
+.IR rev .
+If a branch is given, lock the latest revision on that branch.
+If
+.I rev
+is omitted, lock the latest revision on the default branch.
+Locking prevents overlapping changes.
+If someone else already holds the lock, the lock is broken as with
+.B "rcs\ \-u"
+(see below).
+.TP
+.BR \-u [\f2rev\fP]
+Unlock the revision with number
+.IR rev .
+If a branch is given, unlock the latest revision on that branch.
+If
+.I rev
+is omitted, remove the latest lock held by the caller.
+Normally, only the locker of a revision can unlock it.
+Somebody else unlocking a revision breaks the lock.
+This causes a mail message to be sent to the original locker.
+The message contains a commentary solicited from the breaker.
+The commentary is terminated by end-of-file or by a line containing
+.BR \&. "\ by"
+itself.
+.TP
+.B \-L
+Set locking to
+.IR strict .
+Strict locking means that the owner
+of an \*r file is not exempt from locking for checkin.
+This option should be used for files that are shared.
+.TP
+.B \-U
+Set locking to non-strict.  Non-strict locking means that the owner of
+a file need not lock a revision for checkin.
+This option should
+.I not
+be used for files that are shared.
+Whether default locking is strict is determined by your system administrator,
+but it is normally strict.
+.TP
+\f3\-m\fP\f2rev\fP\f3:\fP\f2msg\fP
+Replace revision
+.IR rev 's
+log message with
+.IR msg .
+.TP
+.B \-M
+Do not send mail when breaking somebody else's lock.
+This option is not meant for casual use;
+it is meant for programs that warn users by other means, and invoke
+.B "rcs\ \-u"
+only as a low-level lock-breaking operation.
+.TP
+\f3\-n\fP\f2name\fP[\f3:\fP[\f2rev\fP]]
+Associate the symbolic name
+.I name
+with the branch or
+revision
+.IR rev .
+Delete the symbolic name if both
+.B :
+and
+.I rev
+are omitted; otherwise, print an error message if
+.I name
+is already associated with
+another number.
+If
+.I rev
+is symbolic, it is expanded before association.
+A
+.I rev
+consisting of a branch number followed by a
+.B .\&
+stands for the current latest revision in the branch.
+A
+.B :
+with an empty
+.I rev
+stands for the current latest revision on the default branch,
+normally the trunk.
+For example,
+.BI "rcs\ \-n" name ":\ RCS/*"
+associates
+.I name
+with the current latest revision of all the named \*r files;
+this contrasts with
+.BI "rcs\ \-n" name ":$\ RCS/*"
+which associates
+.I name
+with the revision numbers extracted from keyword strings
+in the corresponding working files.
+.TP
+\f3\-N\fP\f2name\fP[\f3:\fP[\f2rev\fP]]
+Act like
+.BR \-n ,
+except override any previous assignment of
+.IR name .
+.TP
+.BI \-o range
+deletes (\*(lqoutdates\*(rq) the revisions given by
+.IR range .
+A range consisting of a single revision number means that revision.
+A range consisting of a branch number means the latest revision on that
+branch.
+A range of the form
+.IB rev1 : rev2
+means
+revisions
+.I rev1
+to
+.I rev2
+on the same branch,
+.BI : rev
+means from the beginning of the branch containing
+.I rev
+up to and including
+.IR rev ,
+and
+.IB rev :
+means
+from revision
+.I rev
+to the end of the branch containing
+.IR rev .
+None of the outdated revisions can have branches or locks.
+.TP
+.B \-q
+Run quietly; do not print diagnostics.
+.TP
+.B \-I
+Run interactively, even if the standard input is not a terminal.
+.TP
+.B \-s\f2state\fP\f1[\fP:\f2rev\fP\f1]\fP
+Set the state attribute of the revision
+.I rev
+to
+.IR state .
+If
+.I rev
+is a branch number, assume the latest revision on that branch.
+If
+.I rev
+is omitted, assume the latest revision on the default branch.
+Any identifier is acceptable for
+.IR state .
+A useful set of states
+is
+.B Exp
+(for experimental),
+.B Stab
+(for stable), and
+.B Rel
+(for
+released).
+By default,
+.BR ci (1)
+sets the state of a revision to
+.BR Exp .
+.TP
+.BR \-t [\f2file\fP]
+Write descriptive text from the contents of the named
+.I file
+into the \*r file, deleting the existing text.
+The
+.IR file
+pathname cannot begin with
+.BR \- .
+If
+.I file
+is omitted, obtain the text from standard input,
+terminated by end-of-file or by a line containing
+.BR \&. "\ by"
+itself.
+Prompt for the text if interaction is possible; see
+.BR \-I .
+With
+.BR \-i ,
+descriptive text is obtained
+even if
+.B \-t
+is not given.
+.TP
+.BI \-t\- string
+Write descriptive text from the
+.I string
+into the \*r file, deleting the existing text.
+.TP
+.B \-T
+Preserve the modification time on the \*r file
+unless a revision is removed.
+This option can suppress extensive recompilation caused by a
+.BR make (1)
+dependency of some copy of the working file on the \*r file.
+Use this option with care; it can suppress recompilation even when it is needed,
+i.e. when a change to the \*r file
+would mean a change to keyword strings in the working file.
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.IR n .
+See
+.BR co (1)
+for details.
+.TP
+.BI \-x "suffixes"
+Use
+.I suffixes
+to characterize \*r files.
+See
+.BR ci (1)
+for details.
+.TP
+.BI \-z zone
+Use
+.I zone
+as the default time zone.
+This option has no effect;
+it is present for compatibility with other \*r commands.
+.PP
+At least one explicit option must be given,
+to ensure compatibility with future planned extensions
+to the
+.B rcs
+command.
+.SH COMPATIBILITY
+The
+.BI \-b rev
+option generates an \*r file that cannot be parsed by \*r version 3 or earlier.
+.PP
+The
+.BI \-k subst
+options (except
+.BR \-kkv )
+generate an \*r file that cannot be parsed by \*r version 4 or earlier.
+.PP
+Use
+.BI "rcs \-V" n
+to make an \*r file acceptable to \*r version
+.I n
+by discarding information that would confuse version
+.IR n .
+.PP
+\*r version 5.5 and earlier does not support the
+.B \-x
+option, and requires a
+.B ,v
+suffix on an \*r pathname.
+.SH FILES
+.B rcs
+accesses files much as
+.BR ci (1)
+does,
+except that it uses the effective user for all accesses,
+it does not write the working file or its directory,
+and it does not even read the working file unless a revision number of
+.B $
+is specified.
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+See
+.BR ci (1)
+for details.
+.SH DIAGNOSTICS
+The \*r pathname and the revisions outdated are written to
+the diagnostic output.
+The exit status is zero if and only if all operations were successful.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH "SEE ALSO"
+rcsintro(1), co(1), ci(1), ident(1), rcsclean(1), rcsdiff(1),
+rcsmerge(1), rlog(1), rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.SH BUGS
+A catastrophe (e.g. a system crash) can cause \*r to leave behind
+a semaphore file that causes later invocations of \*r to claim
+that the \*r file is in use.
+To fix this, remove the semaphore file.
+A semaphore file's name typically begins with
+.B ,
+or ends with
+.BR _ .
+.PP
+The separator for revision ranges in the
+.B \-o
+option used to be
+.B \-
+instead of
+.BR : ,
+but this leads to confusion when symbolic names contain
+.BR \- .
+For backwards compatibility
+.B "rcs \-o"
+still supports the old
+.B \-
+separator, but it warns about this obsolete use.
+.PP
+Symbolic names need not refer to existing revisions or branches.
+For example, the
+.B \-o
+option does not remove symbolic names for the outdated revisions; you must use
+.B \-n
+to remove the names.
+.br
diff --git a/gnu/usr.bin/rcs/rcs/rcs.c b/gnu/usr.bin/rcs/rcs/rcs.c
new file mode 100644
index 0000000000000..dfb622a6f8082
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcs/rcs.c
@@ -0,0 +1,1629 @@
+/* Change RCS file attributes.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.21  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.20  1995/06/01 16:23:43  eggert
+ * (main): Warn if no options were given.  Punctuate messages properly.
+ *
+ * (sendmail): Rewind mailmess before flushing it.
+ * Output another warning if mail should work but fails.
+ *
+ * (buildeltatext): Pass "--binary" if -kb and if --binary makes a difference.
+ *
+ * Revision 5.19  1994/03/17 14:05:48  eggert
+ * Use ORCSerror to clean up after a fatal error.  Remove lint.
+ * Specify subprocess input via file descriptor, not file name.  Remove lint.
+ * Flush stderr after prompt.
+ *
+ * Revision 5.18  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.  Don't print usage twice.
+ *
+ * Revision 5.17  1993/11/03 17:42:27  eggert
+ * Add -z.  Don't lose track of -m or -t when there are no other changes.
+ * Don't discard ignored phrases.  Improve quality of diagnostics.
+ *
+ * Revision 5.16  1992/07/28  16:12:44  eggert
+ * rcs -l now asks whether you want to break the lock.
+ * Add -V.  Set RCS file's mode and time at right moment.
+ *
+ * Revision 5.15  1992/02/17  23:02:20  eggert
+ * Add -T.
+ *
+ * Revision 5.14  1992/01/27  16:42:53  eggert
+ * Add -M.  Avoid invoking umask(); it's one less thing to configure.
+ * Add support for bad_creat0.  lint -> RCS_lint
+ *
+ * Revision 5.13  1992/01/06  02:42:34  eggert
+ * Avoid changing RCS file in common cases where no change can occur.
+ *
+ * Revision 5.12  1991/11/20  17:58:08  eggert
+ * Don't read the delta tree from a nonexistent RCS file.
+ *
+ * Revision 5.11  1991/10/07  17:32:46  eggert
+ * Remove lint.
+ *
+ * Revision 5.10  1991/08/19  23:17:54  eggert
+ * Add -m, -r$, piece tables.  Revision separator is `:', not `-'.  Tune.
+ *
+ * Revision 5.9  1991/04/21  11:58:18  eggert
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.8  1991/02/25  07:12:38  eggert
+ * strsave -> str_save (DG/UX name clash)
+ * 0444 -> S_IRUSR|S_IRGRP|S_IROTH for portability
+ *
+ * Revision 5.7  1990/12/18  17:19:21  eggert
+ * Fix bug with multiple -n and -N options.
+ *
+ * Revision 5.6  1990/12/04  05:18:40  eggert
+ * Use -I for prompts and -q for diagnostics.
+ *
+ * Revision 5.5  1990/11/11  00:06:35  eggert
+ * Fix `rcs -e' core dump.
+ *
+ * Revision 5.4  1990/11/01  05:03:33  eggert
+ * Add -I and new -t behavior.  Permit arbitrary data in logs.
+ *
+ * Revision 5.3  1990/10/04  06:30:16  eggert
+ * Accumulate exit status across files.
+ *
+ * Revision 5.2  1990/09/04  08:02:17  eggert
+ * Standardize yes-or-no procedure.
+ *
+ * Revision 5.1  1990/08/29  07:13:51  eggert
+ * Remove unused setuid support.  Clean old log messages too.
+ *
+ * Revision 5.0  1990/08/22  08:12:42  eggert
+ * Don't lose names when applying -a option to multiple files.
+ * Remove compile-time limits; use malloc instead.  Add setuid support.
+ * Permit dates past 1999/12/31.  Make lock and temp files faster and safer.
+ * Ansify and Posixate.  Add -V.  Fix umask bug.  Make linting easier.  Tune.
+ * Yield proper exit status.  Check diff's output.
+ *
+ * Revision 4.11  89/05/01  15:12:06  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.10  88/11/08  16:01:54  narten
+ * didn't install previous patch correctly
+ *
+ * Revision 4.9  88/11/08  13:56:01  narten
+ * removed include <sysexits.h> (not needed)
+ * minor fix for -A option
+ *
+ * Revision 4.8  88/08/09  19:12:27  eggert
+ * Don't access freed storage.
+ * Use execv(), not system(); yield proper exit status; remove lint.
+ *
+ * Revision 4.7  87/12/18  11:37:17  narten
+ * lint cleanups (Guy Harris)
+ *
+ * Revision 4.6  87/10/18  10:28:48  narten
+ * Updating verison numbers. Changes relative to 1.1 are actually
+ * relative to 4.3
+ *
+ * Revision 1.4  87/09/24  13:58:52  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.3  87/03/27  14:21:55  jenkins
+ * Port to suns
+ *
+ * Revision 1.2  85/12/17  13:59:09  albitz
+ * Changed setstate to rcs_setstate because of conflict with random.o.
+ *
+ * Revision 4.3  83/12/15  12:27:33  wft
+ * rcs -u now breaks most recent lock if it can't find a lock by the caller.
+ *
+ * Revision 4.2  83/12/05  10:18:20  wft
+ * Added conditional compilation for sending mail.
+ * Alternatives: V4_2BSD, V6, USG, and other.
+ *
+ * Revision 4.1  83/05/10  16:43:02  wft
+ * Simplified breaklock(); added calls to findlock() and getcaller().
+ * Added option -b (default branch). Updated -s and -w for -b.
+ * Removed calls to stat(); now done by pairfilenames().
+ * Replaced most catchints() calls with restoreints().
+ * Removed check for exit status of delivermail().
+ * Directed all interactive output to stderr.
+ *
+ * Revision 3.9.1.1  83/12/02  22:08:51  wft
+ * Added conditional compilation for 4.2 sendmail and 4.1 delivermail.
+ *
+ * Revision 3.9  83/02/15  15:38:39  wft
+ * Added call to fastcopy() to copy remainder of RCS file.
+ *
+ * Revision 3.8  83/01/18  17:37:51  wft
+ * Changed sendmail(): now uses delivermail, and asks whether to break the lock.
+ *
+ * Revision 3.7  83/01/15  18:04:25  wft
+ * Removed putree(); replaced with puttree() in rcssyn.c.
+ * Combined putdellog() and scanlogtext(); deleted putdellog().
+ * Cleaned up diagnostics and error messages. Fixed problem with
+ * mutilated files in case of deletions in 2 files in a single command.
+ * Changed marking of selector from 'D' to DELETE.
+ *
+ * Revision 3.6  83/01/14  15:37:31  wft
+ * Added ignoring of interrupts while new RCS file is renamed;
+ * Avoids deletion of RCS files by interrupts.
+ *
+ * Revision 3.5  82/12/10  21:11:39  wft
+ * Removed unused variables, fixed checking of return code from diff,
+ * introduced variant COMPAT2 for skipping Suffix on -A files.
+ *
+ * Revision 3.4  82/12/04  13:18:20  wft
+ * Replaced getdelta() with gettree(), changed breaklock to update
+ * field lockedby, added some diagnostics.
+ *
+ * Revision 3.3  82/12/03  17:08:04  wft
+ * Replaced getlogin() with getpwuid(), flcose() with ffclose(),
+ * /usr/ucb/Mail with macro MAIL. Removed handling of Suffix (-x).
+ * fixed -u for missing revno. Disambiguated structure members.
+ *
+ * Revision 3.2  82/10/18  21:05:07  wft
+ * rcs -i now generates a file mode given by the umask minus write permission;
+ * otherwise, rcs keeps the mode, but removes write permission.
+ * I added a check for write error, fixed call to getlogin(), replaced
+ * curdir() with getfullRCSname(), cleaned up handling -U/L, and changed
+ * conflicting, long identifiers.
+ *
+ * Revision 3.1  82/10/13  16:11:07  wft
+ * fixed type of variables receiving from getc() (char -> int).
+ */
+
+
+#include "rcsbase.h"
+
+struct  Lockrev {
+	char const *revno;
+        struct  Lockrev   * nextrev;
+};
+
+struct  Symrev {
+	char const *revno;
+	char const *ssymbol;
+        int     override;
+        struct  Symrev  * nextsym;
+};
+
+struct Message {
+	char const *revno;
+	struct cbuf message;
+	struct Message *nextmessage;
+};
+
+struct  Status {
+	char const *revno;
+	char const *status;
+        struct  Status  * nextstatus;
+};
+
+enum changeaccess {append, erase};
+struct chaccess {
+	char const *login;
+	enum changeaccess command;
+	struct chaccess *nextchaccess;
+};
+
+struct delrevpair {
+	char const *strt;
+	char const *end;
+        int     code;
+};
+
+static int branchpoint P((struct hshentry*,struct hshentry*));
+static int breaklock P((struct hshentry const*));
+static int buildeltatext P((struct hshentries const*));
+static int doaccess P((void));
+static int doassoc P((void));
+static int dolocks P((void));
+static int domessages P((void));
+static int rcs_setstate P((char const*,char const*));
+static int removerevs P((void));
+static int sendmail P((char const*,char const*));
+static int setlock P((char const*));
+static struct Lockrev **rmnewlocklst P((char const*));
+static struct hshentry *searchcutpt P((char const*,int,struct hshentries*));
+static void buildtree P((void));
+static void cleanup P((void));
+static void getaccessor P((char*,enum changeaccess));
+static void getassoclst P((int,char*));
+static void getchaccess P((char const*,enum changeaccess));
+static void getdelrev P((char*));
+static void getmessage P((char*));
+static void getstates P((char*));
+static void scanlogtext P((struct hshentry*,int));
+
+static struct buf numrev;
+static char const *headstate;
+static int chgheadstate, exitstatus, lockhead, unlockcaller;
+static int suppress_mail;
+static struct Lockrev *newlocklst, *rmvlocklst;
+static struct Message *messagelst, **nextmessage;
+static struct Status *statelst, **nextstate;
+static struct Symrev *assoclst, **nextassoc;
+static struct chaccess *chaccess, **nextchaccess;
+static struct delrevpair delrev;
+static struct hshentry *cuthead, *cuttail, *delstrt;
+static struct hshentries *gendeltas;
+
+mainProg(rcsId, "rcs", "$FreeBSD$")
+{
+	static char const cmdusage[] =
+		"\nrcs usage: rcs -{ae}logins -Afile -{blu}[rev] -cstring -{iILqTU} -ksubst -mrev:msg -{nN}name[:[rev]] -orange -sstate[:rev] -t[text] -Vn -xsuff -zzone file ...";
+
+	char *a, **newargv, *textfile;
+	char const *branchsym, *commsyml;
+	int branchflag, changed, expmode, initflag;
+	int strictlock, strict_selected, textflag;
+	int keepRCStime, Ttimeflag;
+	size_t commsymlen;
+	struct buf branchnum;
+	struct Lockrev *lockpt;
+	struct Lockrev **curlock, **rmvlock;
+        struct  Status  * curstate;
+
+	nosetid();
+
+	nextassoc = &assoclst;
+	nextchaccess = &chaccess;
+	nextmessage = &messagelst;
+	nextstate = &statelst;
+	branchsym = commsyml = textfile = 0;
+	branchflag = strictlock = false;
+	bufautobegin(&branchnum);
+	commsymlen = 0;
+	curlock = &newlocklst;
+	rmvlock = &rmvlocklst;
+	expmode = -1;
+	suffixes = X_DEFAULT;
+        initflag= textflag = false;
+        strict_selected = 0;
+	Ttimeflag = false;
+
+        /*  preprocessing command options    */
+	if (1 < argc  &&  argv[1][0] != '-')
+		warn("No options were given; this usage is obsolescent.");
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	while (a = *++argv,  0<--argc && *a++=='-') {
+		switch (*a++) {
+
+		case 'i':   /*  initial version  */
+                        initflag = true;
+                        break;
+
+                case 'b':  /* change default branch */
+			if (branchflag) redefined('b');
+                        branchflag= true;
+			branchsym = a;
+                        break;
+
+                case 'c':   /*  change comment symbol   */
+			if (commsyml) redefined('c');
+			commsyml = a;
+			commsymlen = strlen(a);
+                        break;
+
+                case 'a':  /*  add new accessor   */
+			getaccessor(*argv+1, append);
+                        break;
+
+                case 'A':  /*  append access list according to accessfile  */
+			if (!*a) {
+			    error("missing pathname after -A");
+                            break;
+                        }
+			*argv = a;
+			if (0 < pairnames(1,argv,rcsreadopen,true,false)) {
+			    while (AccessList) {
+				getchaccess(str_save(AccessList->login),append);
+				AccessList = AccessList->nextaccess;
+			    }
+			    Izclose(&finptr);
+                        }
+                        break;
+
+                case 'e':    /*  remove accessors   */
+			getaccessor(*argv+1, erase);
+                        break;
+
+                case 'l':    /*   lock a revision if it is unlocked   */
+			if (!*a) {
+			    /* Lock head or default branch.  */
+                            lockhead = true;
+                            break;
+                        }
+			*curlock = lockpt = talloc(struct Lockrev);
+			lockpt->revno = a;
+			lockpt->nextrev = 0;
+			curlock = &lockpt->nextrev;
+                        break;
+
+                case 'u':   /*  release lock of a locked revision   */
+			if (!*a) {
+                            unlockcaller=true;
+                            break;
+                        }
+			*rmvlock = lockpt = talloc(struct Lockrev);
+			lockpt->revno = a;
+			lockpt->nextrev = 0;
+			rmvlock = &lockpt->nextrev;
+			curlock = rmnewlocklst(lockpt->revno);
+                        break;
+
+                case 'L':   /*  set strict locking */
+			if (strict_selected) {
+			   if (!strictlock)	  /* Already selected -U? */
+			       warn("-U overridden by -L");
+                        }
+                        strictlock = true;
+			strict_selected = true;
+                        break;
+
+                case 'U':   /*  release strict locking */
+			if (strict_selected) {
+			   if (strictlock)	  /* Already selected -L? */
+			       warn("-L overridden by -U");
+                        }
+			strict_selected = true;
+                        break;
+
+                case 'n':    /*  add new association: error, if name exists */
+			if (!*a) {
+			    error("missing symbolic name after -n");
+                            break;
+                        }
+                        getassoclst(false, (*argv)+1);
+                        break;
+
+                case 'N':   /*  add or change association   */
+			if (!*a) {
+			    error("missing symbolic name after -N");
+                            break;
+                        }
+                        getassoclst(true, (*argv)+1);
+                        break;
+
+		case 'm':   /*  change log message  */
+			getmessage(a);
+			break;
+
+		case 'M':   /*  do not send mail */
+			suppress_mail = true;
+			break;
+
+		case 'o':   /*  delete revisions  */
+			if (delrev.strt) redefined('o');
+			if (!*a) {
+			    error("missing revision range after -o");
+                            break;
+                        }
+                        getdelrev( (*argv)+1 );
+                        break;
+
+                case 's':   /*  change state attribute of a revision  */
+			if (!*a) {
+			    error("state missing after -s");
+                            break;
+                        }
+                        getstates( (*argv)+1);
+                        break;
+
+                case 't':   /*  change descriptive text   */
+                        textflag=true;
+			if (*a) {
+				if (textfile) redefined('t');
+				textfile = a;
+                        }
+                        break;
+
+		case 'T':  /*  do not update last-mod time for minor changes */
+			if (*a)
+				goto unknown;
+			Ttimeflag = true;
+			break;
+
+		case 'I':
+			interactiveflag = true;
+			break;
+
+                case 'q':
+                        quietflag = true;
+                        break;
+
+		case 'x':
+			suffixes = a;
+			break;
+
+		case 'V':
+			setRCSversion(*argv);
+			break;
+
+		case 'z':
+			zone_set(a);
+			break;
+
+		case 'k':    /*  set keyword expand mode  */
+			if (0 <= expmode) redefined('k');
+			if (0 <= (expmode = str2expmode(a)))
+			    break;
+			/* fall into */
+                default:
+		unknown:
+			error("unknown option: %s%s", *argv, cmdusage);
+                };
+        }  /* end processing of options */
+
+	/* Now handle all pathnames.  */
+	if (nerror) cleanup();
+	else if (argc < 1) faterror("no input file%s", cmdusage);
+	else for (;  0 < argc;  cleanup(), ++argv, --argc) {
+
+	ffree();
+
+        if ( initflag ) {
+	    switch (pairnames(argc, argv, rcswriteopen, false, false)) {
+                case -1: break;        /*  not exist; ok */
+                case  0: continue;     /*  error         */
+		case  1: rcserror("already exists");
+                         continue;
+            }
+	}
+        else  {
+	    switch (pairnames(argc, argv, rcswriteopen, true, false)) {
+                case -1: continue;    /*  not exist      */
+                case  0: continue;    /*  errors         */
+                case  1: break;       /*  file exists; ok*/
+            }
+	}
+
+
+	/*
+	 * RCSname contains the name of the RCS file, and
+	 * workname contains the name of the working file.
+         * if !initflag, finptr contains the file descriptor for the
+         * RCS file. The admin node is initialized.
+         */
+
+	diagnose("RCS file: %s\n", RCSname);
+
+	changed = initflag | textflag;
+	keepRCStime = Ttimeflag;
+	if (!initflag) {
+		if (!checkaccesslist()) continue;
+		gettree(); /* Read the delta tree.  */
+	}
+
+        /*  update admin. node    */
+	if (strict_selected) {
+		changed  |=  StrictLocks ^ strictlock;
+		StrictLocks = strictlock;
+	}
+	if (
+	    commsyml &&
+	    (
+		commsymlen != Comment.size ||
+		memcmp(commsyml, Comment.string, commsymlen) != 0
+	    )
+	) {
+		Comment.string = commsyml;
+		Comment.size = strlen(commsyml);
+		changed = true;
+	}
+	if (0 <= expmode  &&  Expand != expmode) {
+		Expand = expmode;
+		changed = true;
+	}
+
+        /* update default branch */
+	if (branchflag && expandsym(branchsym, &branchnum)) {
+	    if (countnumflds(branchnum.string)) {
+		if (cmpnum(Dbranch, branchnum.string) != 0) {
+			Dbranch = branchnum.string;
+			changed = true;
+		}
+            } else
+		if (Dbranch) {
+			Dbranch = 0;
+			changed = true;
+		}
+	}
+
+	changed |= doaccess();	/* Update access list.  */
+
+	changed |= doassoc();	/* Update association list.  */
+
+	changed |= dolocks();	/* Update locks.  */
+
+	changed |= domessages();	/* Update log messages.  */
+
+        /*  update state attribution  */
+        if (chgheadstate) {
+            /* change state of default branch or head */
+	    if (!Dbranch) {
+		if (!Head)
+		    rcswarn("can't change states in an empty tree");
+		else if (strcmp(Head->state, headstate) != 0) {
+		    Head->state = headstate;
+		    changed = true;
+		}
+	    } else
+		changed |= rcs_setstate(Dbranch,headstate);
+        }
+	for (curstate = statelst;  curstate;  curstate = curstate->nextstatus)
+	    changed |= rcs_setstate(curstate->revno,curstate->status);
+
+	cuthead = cuttail = 0;
+	if (delrev.strt && removerevs()) {
+            /*  rebuild delta tree if some deltas are deleted   */
+            if ( cuttail )
+		VOID genrevs(
+			cuttail->num, (char *)0, (char *)0, (char *)0,
+			&gendeltas
+		);
+            buildtree();
+	    changed = true;
+	    keepRCStime = false;
+        }
+
+	if (nerror)
+		continue;
+
+	putadmin();
+        if ( Head )
+           puttree(Head, frewrite);
+	putdesc(textflag,textfile);
+
+        if ( Head) {
+	    if (delrev.strt || messagelst) {
+		if (!cuttail || buildeltatext(gendeltas)) {
+		    advise_access(finptr, MADV_SEQUENTIAL);
+		    scanlogtext((struct hshentry *)0, false);
+                    /* copy rest of delta text nodes that are not deleted      */
+		    changed = true;
+		}
+            }
+        }
+
+	if (initflag) {
+		/* Adjust things for donerewrite's sake.  */
+		if (stat(workname, &RCSstat) != 0) {
+#		    if bad_creat0
+			mode_t m = umask(0);
+			(void) umask(m);
+			RCSstat.st_mode = (S_IRUSR|S_IRGRP|S_IROTH) & ~m;
+#		    else
+			changed = -1;
+#		    endif
+		}
+		RCSstat.st_nlink = 0;
+		keepRCStime = false;
+	}
+	if (donerewrite(changed,
+		keepRCStime ? RCSstat.st_mtime : (time_t)-1
+	) != 0)
+	    break;
+
+	diagnose("done\n");
+	}
+
+	tempunlink();
+	exitmain(exitstatus);
+}       /* end of main (rcs) */
+
+	static void
+cleanup()
+{
+	if (nerror) exitstatus = EXIT_FAILURE;
+	Izclose(&finptr);
+	Ozclose(&fcopy);
+	ORCSclose();
+	dirtempunlink();
+}
+
+	void
+exiterr()
+{
+	ORCSerror();
+	dirtempunlink();
+	tempunlink();
+	_exit(EXIT_FAILURE);
+}
+
+
+	static void
+getassoclst(flag, sp)
+int     flag;
+char    * sp;
+/*  Function:   associate a symbolic name to a revision or branch,      */
+/*              and store in assoclst                                   */
+
+{
+        struct   Symrev  * pt;
+	char const *temp;
+        int                c;
+
+	while ((c = *++sp) == ' ' || c == '\t' || c =='\n')
+	    continue;
+        temp = sp;
+	sp = checksym(sp, ':');  /*  check for invalid symbolic name  */
+	c = *sp;   *sp = '\0';
+        while( c == ' ' || c == '\t' || c == '\n')  c = *++sp;
+
+        if ( c != ':' && c != '\0') {
+	    error("invalid string %s after option -n or -N",sp);
+            return;
+        }
+
+	pt = talloc(struct Symrev);
+        pt->ssymbol = temp;
+        pt->override = flag;
+	if (c == '\0')  /*  delete symbol  */
+	    pt->revno = 0;
+        else {
+	    while ((c = *++sp) == ' ' || c == '\n' || c == '\t')
+		continue;
+	    pt->revno = sp;
+        }
+	pt->nextsym = 0;
+	*nextassoc = pt;
+	nextassoc = &pt->nextsym;
+}
+
+
+	static void
+getchaccess(login, command)
+	char const *login;
+	enum changeaccess command;
+{
+	register struct chaccess *pt;
+
+	pt = talloc(struct chaccess);
+	pt->login = login;
+	pt->command = command;
+	pt->nextchaccess = 0;
+	*nextchaccess = pt;
+	nextchaccess = &pt->nextchaccess;
+}
+
+
+
+	static void
+getaccessor(opt, command)
+	char *opt;
+	enum changeaccess command;
+/*   Function:  get the accessor list of options -e and -a,     */
+/*		and store in chaccess				*/
+
+
+{
+        register c;
+	register char *sp;
+
+	sp = opt;
+	while ((c = *++sp) == ' ' || c == '\n' || c == '\t' || c == ',')
+	    continue;
+        if ( c == '\0') {
+	    if (command == erase  &&  sp-opt == 1) {
+		getchaccess((char*)0, command);
+		return;
+	    }
+	    error("missing login name after option -a or -e");
+	    return;
+        }
+
+        while( c != '\0') {
+		getchaccess(sp, command);
+		sp = checkid(sp,',');
+		c = *sp;   *sp = '\0';
+                while( c == ' ' || c == '\n' || c == '\t'|| c == ',')c =(*++sp);
+        }
+}
+
+
+	static void
+getmessage(option)
+	char *option;
+{
+	struct Message *pt;
+	struct cbuf cb;
+	char *m;
+
+	if (!(m = strchr(option, ':'))) {
+		error("-m option lacks revision number");
+		return;
+	}
+	*m++ = 0;
+	cb = cleanlogmsg(m, strlen(m));
+	if (!cb.size) {
+		error("-m option lacks log message");
+		return;
+	}
+	pt = talloc(struct Message);
+	pt->revno = option;
+	pt->message = cb;
+	pt->nextmessage = 0;
+	*nextmessage = pt;
+	nextmessage = &pt->nextmessage;
+}
+
+
+	static void
+getstates(sp)
+char    *sp;
+/*   Function:  get one state attribute and the corresponding   */
+/*              revision and store in statelst                  */
+
+{
+	char const *temp;
+        struct  Status  *pt;
+        register        c;
+
+	while ((c = *++sp) ==' ' || c == '\t' || c == '\n')
+	    continue;
+        temp = sp;
+	sp = checkid(sp,':');  /* check for invalid state attribute */
+	c = *sp;   *sp = '\0';
+        while( c == ' ' || c == '\t' || c == '\n' )  c = *++sp;
+
+        if ( c == '\0' ) {  /*  change state of def. branch or Head  */
+            chgheadstate = true;
+            headstate  = temp;
+            return;
+        }
+        else if ( c != ':' ) {
+	    error("missing ':' after state in option -s");
+            return;
+        }
+
+	while ((c = *++sp) == ' ' || c == '\t' || c == '\n')
+	    continue;
+	pt = talloc(struct Status);
+        pt->status     = temp;
+        pt->revno      = sp;
+	pt->nextstatus = 0;
+	*nextstate = pt;
+	nextstate = &pt->nextstatus;
+}
+
+
+
+	static void
+getdelrev(sp)
+char    *sp;
+/*   Function:  get revision range or branch to be deleted,     */
+/*              and place in delrev                             */
+{
+        int    c;
+        struct  delrevpair      *pt;
+	int separator;
+
+	pt = &delrev;
+	while ((c = (*++sp)) == ' ' || c == '\n' || c == '\t')
+		continue;
+
+	/* Support old ambiguous '-' syntax; this will go away.  */
+	if (strchr(sp,':'))
+		separator = ':';
+	else {
+		if (strchr(sp,'-')  &&  VERSION(5) <= RCSversion)
+		    warn("`-' is obsolete in `-o%s'; use `:' instead", sp);
+		separator = '-';
+	}
+
+	if (c == separator) { /* -o:rev */
+	    while ((c = (*++sp)) == ' ' || c == '\n' || c == '\t')
+		continue;
+            pt->strt = sp;    pt->code = 1;
+            while( c != ' ' && c != '\n' && c != '\t' && c != '\0') c =(*++sp);
+            *sp = '\0';
+	    pt->end = 0;
+            return;
+        }
+        else {
+            pt->strt = sp;
+            while( c != ' ' && c != '\n' && c != '\t' && c != '\0'
+		   && c != separator )  c = *++sp;
+            *sp = '\0';
+            while( c == ' ' || c == '\n' || c == '\t' )  c = *++sp;
+            if ( c == '\0' )  {  /*   -o rev or branch   */
+		pt->code = 0;
+		pt->end = 0;
+                return;
+            }
+	    if (c != separator) {
+		error("invalid range %s %s after -o", pt->strt, sp);
+            }
+	    while ((c = *++sp) == ' ' || c == '\n' || c == '\t')
+		continue;
+	    if (!c) {  /* -orev: */
+		pt->code = 2;
+		pt->end = 0;
+                return;
+            }
+        }
+	/* -orev1:rev2 */
+	pt->end = sp;  pt->code = 3;
+        while( c!= ' ' && c != '\n' && c != '\t' && c != '\0') c = *++sp;
+        *sp = '\0';
+}
+
+
+
+
+	static void
+scanlogtext(delta,edit)
+	struct hshentry *delta;
+	int edit;
+/* Function: Scans delta text nodes up to and including the one given
+ * by delta, or up to last one present, if !delta.
+ * For the one given by delta (if delta), the log message is saved into
+ * delta->log if delta==cuttail; the text is edited if EDIT is set, else copied.
+ * Assumes the initial lexeme must be read in first.
+ * Does not advance nexttok after it is finished, except if !delta.
+ */
+{
+	struct hshentry const *nextdelta;
+	struct cbuf cb;
+
+	for (;;) {
+		foutptr = 0;
+		if (eoflex()) {
+                    if(delta)
+			rcsfaterror("can't find delta for revision %s",
+				delta->num
+			);
+		    return; /* no more delta text nodes */
+                }
+		nextlex();
+		if (!(nextdelta=getnum()))
+			fatserror("delta number corrupted");
+		if (nextdelta->selector) {
+			foutptr = frewrite;
+			aprintf(frewrite,DELNUMFORM,nextdelta->num,Klog);
+                }
+		getkeystring(Klog);
+		if (nextdelta == cuttail) {
+			cb = savestring(&curlogbuf);
+			if (!delta->log.string)
+			    delta->log = cleanlogmsg(curlogbuf.string, cb.size);
+			nextlex();
+			delta->igtext = getphrases(Ktext);
+		} else {
+			if (nextdelta->log.string && nextdelta->selector) {
+				foutptr = 0;
+				readstring();
+				foutptr = frewrite;
+				putstring(foutptr, false, nextdelta->log, true);
+				afputc(nextc, foutptr);
+			} else
+				readstring();
+			ignorephrases(Ktext);
+		}
+		getkeystring(Ktext);
+
+		if (delta==nextdelta)
+			break;
+		readstring(); /* skip over it */
+
+	}
+	/* got the one we're looking for */
+	if (edit)
+		editstring((struct hshentry*)0);
+	else
+		enterstring();
+}
+
+
+
+	static struct Lockrev **
+rmnewlocklst(which)
+	char const *which;
+/* Remove lock to revision WHICH from newlocklst.  */
+{
+	struct Lockrev *pt, **pre;
+
+	pre = &newlocklst;
+	while ((pt = *pre))
+	    if (strcmp(pt->revno, which) != 0)
+		pre = &pt->nextrev;
+	    else {
+		*pre = pt->nextrev;
+		tfree(pt);
+	    }
+        return pre;
+}
+
+
+
+	static int
+doaccess()
+{
+	register struct chaccess *ch;
+	register struct access **p, *t;
+	register int changed = false;
+
+	for (ch = chaccess;  ch;  ch = ch->nextchaccess) {
+		switch (ch->command) {
+		case erase:
+			if (!ch->login) {
+			    if (AccessList) {
+				AccessList = 0;
+				changed = true;
+			    }
+			} else
+			    for (p = &AccessList; (t = *p); p = &t->nextaccess)
+				if (strcmp(ch->login, t->login) == 0) {
+					*p = t->nextaccess;
+					changed = true;
+					break;
+				}
+			break;
+		case append:
+			for (p = &AccessList;  ;  p = &t->nextaccess)
+				if (!(t = *p)) {
+					*p = t = ftalloc(struct access);
+					t->login = ch->login;
+					t->nextaccess = 0;
+					changed = true;
+					break;
+				} else if (strcmp(ch->login, t->login) == 0)
+					break;
+			break;
+		}
+	}
+	return changed;
+}
+
+
+	static int
+sendmail(Delta, who)
+	char const *Delta, *who;
+/*   Function:  mail to who, informing him that his lock on delta was
+ *   broken by caller. Ask first whether to go ahead. Return false on
+ *   error or if user decides not to break the lock.
+ */
+{
+#ifdef SENDMAIL
+	char const *messagefile;
+	int old1, old2, c, status;
+        FILE    * mailmess;
+#endif
+
+
+	aprintf(stderr, "Revision %s is already locked by %s.\n", Delta, who);
+	if (suppress_mail)
+		return true;
+	if (!yesorno(false, "Do you want to break the lock? [ny](n): "))
+		return false;
+
+        /* go ahead with breaking  */
+#ifdef SENDMAIL
+	messagefile = maketemp(0);
+	if (!(mailmess = fopenSafer(messagefile, "w+"))) {
+	    efaterror(messagefile);
+        }
+
+	aprintf(mailmess, "Subject: Broken lock on %s\n\nYour lock on revision %s of file %s\nhas been broken by %s for the following reason:\n",
+		basefilename(RCSname), Delta, getfullRCSname(), getcaller()
+	);
+	aputs("State the reason for breaking the lock:\n(terminate with single '.' or end of file)\n>> ", stderr);
+	eflush();
+
+        old1 = '\n';    old2 = ' ';
+        for (; ;) {
+	    c = getcstdin();
+	    if (feof(stdin)) {
+		aprintf(mailmess, "%c\n", old1);
+                break;
+            }
+            else if ( c == '\n' && old1 == '.' && old2 == '\n')
+                break;
+            else {
+		afputc(old1, mailmess);
+                old2 = old1;   old1 = c;
+		if (c == '\n') {
+		    aputs(">> ", stderr);
+		    eflush();
+		}
+            }
+        }
+	Orewind(mailmess);
+	aflush(mailmess);
+	status = run(fileno(mailmess), (char*)0, SENDMAIL, who, (char*)0);
+	Ozclose(&mailmess);
+	if (status == 0)
+		return true;
+	warn("Mail failed.");
+#endif
+	warn("Mail notification of broken locks is not available.");
+	warn("Please tell `%s' why you broke the lock.", who);
+	return(true);
+}
+
+
+
+	static int
+breaklock(delta)
+	struct hshentry const *delta;
+/* function: Finds the lock held by caller on delta,
+ * and removes it.
+ * Sends mail if a lock different from the caller's is broken.
+ * Prints an error message if there is no such lock or error.
+ */
+{
+	register struct rcslock *next, **trail;
+	char const *num;
+
+	num=delta->num;
+	for (trail = &Locks;  (next = *trail);  trail = &next->nextlock)
+		if (strcmp(num, next->delta->num) == 0) {
+			if (
+				strcmp(getcaller(),next->login) != 0
+			    &&	!sendmail(num, next->login)
+			) {
+			    rcserror("revision %s still locked by %s",
+				num, next->login
+			    );
+			    return false;
+			}
+			diagnose("%s unlocked\n", next->delta->num);
+			*trail = next->nextlock;
+			next->delta->lockedby = 0;
+			return true;
+                }
+	rcserror("no lock set on revision %s", num);
+	return false;
+}
+
+
+
+	static struct hshentry *
+searchcutpt(object, length, store)
+	char const *object;
+	int length;
+	struct hshentries *store;
+/*   Function:  Search store and return entry with number being object. */
+/*		cuttail = 0, if the entry is Head; otherwise, cuttail   */
+/*              is the entry point to the one with number being object  */
+
+{
+	cuthead = 0;
+	while (compartial(store->first->num, object, length)) {
+		cuthead = store->first;
+		store = store->rest;
+	}
+	return store->first;
+}
+
+
+
+	static int
+branchpoint(strt, tail)
+struct  hshentry        *strt,  *tail;
+/*   Function: check whether the deltas between strt and tail	*/
+/*		are locked or branch point, return 1 if any is  */
+/*		locked or branch point; otherwise, return 0 and */
+/*		mark deleted					*/
+
+{
+        struct  hshentry    *pt;
+	struct rcslock const *lockpt;
+
+	for (pt = strt;  pt != tail;  pt = pt->next) {
+            if ( pt->branches ){ /*  a branch point  */
+		rcserror("can't remove branch point %s", pt->num);
+		return true;
+            }
+	    for (lockpt = Locks;  lockpt;  lockpt = lockpt->nextlock)
+		if (lockpt->delta == pt) {
+		    rcserror("can't remove locked revision %s", pt->num);
+		    return true;
+		}
+	    pt->selector = false;
+	    diagnose("deleting revision %s\n",pt->num);
+        }
+	return false;
+}
+
+
+
+	static int
+removerevs()
+/*   Function:  get the revision range to be removed, and place the     */
+/*              first revision removed in delstrt, the revision before  */
+/*		delstrt in cuthead (0, if delstrt is head), and the	*/
+/*		revision after the last removed revision in cuttail (0	*/
+/*              if the last is a leaf                                   */
+
+{
+	struct  hshentry *target, *target2, *temp;
+	int length;
+	int cmp;
+
+	if (!expandsym(delrev.strt, &numrev)) return 0;
+	target = genrevs(numrev.string,(char*)0,(char*)0,(char*)0,&gendeltas);
+        if ( ! target ) return 0;
+	cmp = cmpnum(target->num, numrev.string);
+	length = countnumflds(numrev.string);
+
+	if (delrev.code == 0) {  /*  -o  rev    or    -o  branch   */
+	    if (length & 1)
+		temp=searchcutpt(target->num,length+1,gendeltas);
+	    else if (cmp) {
+		rcserror("Revision %s doesn't exist.", numrev.string);
+		return 0;
+	    }
+	    else
+		temp = searchcutpt(numrev.string, length, gendeltas);
+	    cuttail = target->next;
+            if ( branchpoint(temp, cuttail) ) {
+		cuttail = 0;
+                return 0;
+            }
+            delstrt = temp;     /* first revision to be removed   */
+            return 1;
+        }
+
+	if (length & 1) {   /*  invalid branch after -o   */
+	    rcserror("invalid branch range %s after -o", numrev.string);
+            return 0;
+        }
+
+	if (delrev.code == 1) {  /*  -o  -rev   */
+            if ( length > 2 ) {
+                temp = searchcutpt( target->num, length-1, gendeltas);
+                cuttail = target->next;
+            }
+            else {
+                temp = searchcutpt(target->num, length, gendeltas);
+                cuttail = target;
+                while( cuttail && ! cmpnumfld(target->num,cuttail->num,1) )
+                    cuttail = cuttail->next;
+            }
+            if ( branchpoint(temp, cuttail) ){
+		cuttail = 0;
+                return 0;
+            }
+            delstrt = temp;
+            return 1;
+        }
+
+	if (delrev.code == 2) {   /*  -o  rev-   */
+            if ( length == 2 ) {
+                temp = searchcutpt(target->num, 1,gendeltas);
+		if (cmp)
+                    cuttail = target;
+                else
+                    cuttail = target->next;
+            }
+            else  {
+		if (cmp) {
+                    cuthead = target;
+                    if ( !(temp = target->next) ) return 0;
+                }
+                else
+                    temp = searchcutpt(target->num, length, gendeltas);
+		getbranchno(temp->num, &numrev);  /* get branch number */
+		VOID genrevs(numrev.string, (char*)0, (char*)0, (char*)0, &gendeltas);
+            }
+            if ( branchpoint( temp, cuttail ) ) {
+		cuttail = 0;
+                return 0;
+            }
+            delstrt = temp;
+            return 1;
+        }
+
+        /*   -o   rev1-rev2   */
+	if (!expandsym(delrev.end, &numrev)) return 0;
+	if (
+		length != countnumflds(numrev.string)
+	    ||	(length>2 && compartial(numrev.string, target->num, length-1))
+	) {
+	    rcserror("invalid revision range %s-%s",
+		target->num, numrev.string
+	    );
+            return 0;
+        }
+
+	target2 = genrevs(numrev.string,(char*)0,(char*)0,(char*)0,&gendeltas);
+        if ( ! target2 ) return 0;
+
+        if ( length > 2) {  /* delete revisions on branches  */
+            if ( cmpnum(target->num, target2->num) > 0) {
+		cmp = cmpnum(target2->num, numrev.string);
+                temp = target;
+                target = target2;
+                target2 = temp;
+            }
+	    if (cmp) {
+                if ( ! cmpnum(target->num, target2->num) ) {
+		    rcserror("Revisions %s-%s don't exist.",
+			delrev.strt, delrev.end
+		    );
+                    return 0;
+                }
+                cuthead = target;
+                temp = target->next;
+            }
+            else
+                temp = searchcutpt(target->num, length, gendeltas);
+            cuttail = target2->next;
+        }
+        else { /*  delete revisions on trunk  */
+            if ( cmpnum( target->num, target2->num) < 0 ) {
+                temp = target;
+                target = target2;
+                target2 = temp;
+            }
+            else
+		cmp = cmpnum(target2->num, numrev.string);
+	    if (cmp) {
+                if ( ! cmpnum(target->num, target2->num) ) {
+		    rcserror("Revisions %s-%s don't exist.",
+			delrev.strt, delrev.end
+		    );
+                    return 0;
+                }
+                cuttail = target2;
+            }
+            else
+                cuttail = target2->next;
+            temp = searchcutpt(target->num, length, gendeltas);
+        }
+        if ( branchpoint(temp, cuttail) )  {
+	    cuttail = 0;
+            return 0;
+        }
+        delstrt = temp;
+        return 1;
+}
+
+
+
+	static int
+doassoc()
+/* Add or delete (if !revno) association that is stored in assoclst.  */
+{
+	char const *p;
+	int changed = false;
+	struct Symrev const *curassoc;
+	struct assoc **pre, *pt;
+
+        /*  add new associations   */
+	for (curassoc = assoclst;  curassoc;  curassoc = curassoc->nextsym) {
+	    char const *ssymbol = curassoc->ssymbol;
+
+	    if (!curassoc->revno) {  /* delete symbol  */
+		for (pre = &Symbols;  ;  pre = &pt->nextassoc)
+		    if (!(pt = *pre)) {
+			rcswarn("can't delete nonexisting symbol %s", ssymbol);
+			break;
+		    } else if (strcmp(pt->symbol, ssymbol) == 0) {
+			*pre = pt->nextassoc;
+			changed = true;
+			break;
+		    }
+	    }
+	    else {
+		if (curassoc->revno[0]) {
+		    p = 0;
+		    if (expandsym(curassoc->revno, &numrev))
+			p = fstr_save(numrev.string);
+		} else if (!(p = tiprev()))
+		    rcserror("no latest revision to associate with symbol %s",
+			    ssymbol
+		    );
+		if (p)
+		    changed |= addsymbol(p, ssymbol, curassoc->override);
+	    }
+        }
+	return changed;
+}
+
+
+
+	static int
+dolocks()
+/* Function: remove lock for caller or first lock if unlockcaller is set;
+ *           remove locks which are stored in rmvlocklst,
+ *           add new locks which are stored in newlocklst,
+ *           add lock for Dbranch or Head if lockhead is set.
+ */
+{
+	struct Lockrev const *lockpt;
+	struct hshentry *target;
+	int changed = false;
+
+	if (unlockcaller) { /*  find lock for caller  */
+            if ( Head ) {
+		if (Locks) {
+		    switch (findlock(true, &target)) {
+		      case 0:
+			/* remove most recent lock */
+			changed |= breaklock(Locks->delta);
+			break;
+		      case 1:
+			diagnose("%s unlocked\n",target->num);
+			changed = true;
+			break;
+		    }
+		} else {
+		    rcswarn("No locks are set.");
+		}
+            } else {
+		rcswarn("can't unlock an empty tree");
+            }
+        }
+
+        /*  remove locks which are stored in rmvlocklst   */
+	for (lockpt = rmvlocklst;  lockpt;  lockpt = lockpt->nextrev)
+	    if (expandsym(lockpt->revno, &numrev)) {
+		target = genrevs(numrev.string, (char *)0, (char *)0, (char *)0, &gendeltas);
+                if ( target )
+		   if (!(countnumflds(numrev.string)&1) && cmpnum(target->num,numrev.string))
+			rcserror("can't unlock nonexisting revision %s",
+				lockpt->revno
+			);
+                   else
+			changed |= breaklock(target);
+                        /* breaklock does its own diagnose */
+            }
+
+        /*  add new locks which stored in newlocklst  */
+	for (lockpt = newlocklst;  lockpt;  lockpt = lockpt->nextrev)
+	    changed |= setlock(lockpt->revno);
+
+	if (lockhead) /*  lock default branch or head  */
+	    if (Dbranch)
+		changed |= setlock(Dbranch);
+	    else if (Head)
+		changed |= setlock(Head->num);
+	    else
+		rcswarn("can't lock an empty tree");
+	return changed;
+}
+
+
+
+	static int
+setlock(rev)
+	char const *rev;
+/* Function: Given a revision or branch number, finds the corresponding
+ * delta and locks it for caller.
+ */
+{
+        struct  hshentry *target;
+	int r;
+
+	if (expandsym(rev, &numrev)) {
+	    target = genrevs(numrev.string, (char*)0, (char*)0,
+			     (char*)0, &gendeltas);
+            if ( target )
+	       if (!(countnumflds(numrev.string)&1) && cmpnum(target->num,numrev.string))
+		    rcserror("can't lock nonexisting revision %s",
+			numrev.string
+		    );
+	       else {
+		    if ((r = addlock(target, false)) < 0  &&  breaklock(target))
+			r = addlock(target, true);
+		    if (0 <= r) {
+			if (r)
+			    diagnose("%s locked\n", target->num);
+			return r;
+		    }
+	       }
+	}
+	return 0;
+}
+
+
+	static int
+domessages()
+{
+	struct hshentry *target;
+	struct Message *p;
+	int changed = false;
+
+	for (p = messagelst;  p;  p = p->nextmessage)
+	    if (
+		expandsym(p->revno, &numrev)  &&
+		(target = genrevs(
+			numrev.string, (char*)0, (char*)0, (char*)0, &gendeltas
+		))
+	    ) {
+		/*
+		 * We can't check the old log -- it's much later in the file.
+		 * We pessimistically assume that it changed.
+		 */
+		target->log = p->message;
+		changed = true;
+	    }
+	return changed;
+}
+
+
+	static int
+rcs_setstate(rev,status)
+	char const *rev, *status;
+/* Function: Given a revision or branch number, finds the corresponding delta
+ * and sets its state to status.
+ */
+{
+        struct  hshentry *target;
+
+	if (expandsym(rev, &numrev)) {
+	    target = genrevs(numrev.string, (char*)0, (char*)0,
+			     (char*)0, &gendeltas);
+            if ( target )
+	       if (!(countnumflds(numrev.string)&1) && cmpnum(target->num,numrev.string))
+		    rcserror("can't set state of nonexisting revision %s",
+			numrev.string
+		    );
+	       else if (strcmp(target->state, status) != 0) {
+                    target->state = status;
+		    return true;
+	       }
+	}
+	return false;
+}
+
+
+
+
+
+	static int
+buildeltatext(deltas)
+	struct hshentries const *deltas;
+/*   Function:  put the delta text on frewrite and make necessary   */
+/*              change to delta text                                */
+{
+	register FILE *fcut;	/* temporary file to rebuild delta tree */
+	char const *cutname;
+
+	fcut = 0;
+	cuttail->selector = false;
+	scanlogtext(deltas->first, false);
+        if ( cuthead )  {
+	    cutname = maketemp(3);
+	    if (!(fcut = fopenSafer(cutname, FOPEN_WPLUS_WORK))) {
+		efaterror(cutname);
+            }
+
+	    while (deltas->first != cuthead) {
+		deltas = deltas->rest;
+		scanlogtext(deltas->first, true);
+            }
+
+	    snapshotedit(fcut);
+	    Orewind(fcut);
+	    aflush(fcut);
+        }
+
+	while (deltas->first != cuttail)
+	    scanlogtext((deltas = deltas->rest)->first, true);
+	finishedit((struct hshentry*)0, (FILE*)0, true);
+	Ozclose(&fcopy);
+
+	if (fcut) {
+	    char const *diffname = maketemp(0);
+	    char const *diffv[6 + !!OPEN_O_BINARY];
+	    char const **diffp = diffv;
+	    *++diffp = DIFF;
+	    *++diffp = DIFFFLAGS;
+#	    if OPEN_O_BINARY
+		if (Expand == BINARY_EXPAND)
+		    *++diffp == "--binary";
+#	    endif
+	    *++diffp = "-";
+	    *++diffp = resultname;
+	    *++diffp = 0;
+	    switch (runv(fileno(fcut), diffname, diffv)) {
+		case DIFF_FAILURE: case DIFF_SUCCESS: break;
+		default: rcsfaterror("diff failed");
+	    }
+	    Ofclose(fcut);
+	    return putdtext(cuttail,diffname,frewrite,true);
+	} else
+	    return putdtext(cuttail,resultname,frewrite,false);
+}
+
+
+
+	static void
+buildtree()
+/*   Function:  actually removes revisions whose selector field  */
+/*		is false, and rebuilds the linkage of deltas.	 */
+/*              asks for reconfirmation if deleting last revision*/
+{
+	struct	hshentry   * Delta;
+        struct  branchhead      *pt, *pre;
+
+        if ( cuthead )
+           if ( cuthead->next == delstrt )
+                cuthead->next = cuttail;
+           else {
+                pre = pt = cuthead->branches;
+                while( pt && pt->hsh != delstrt )  {
+                    pre = pt;
+                    pt = pt->nextbranch;
+                }
+                if ( cuttail )
+                    pt->hsh = cuttail;
+                else if ( pt == pre )
+                    cuthead->branches = pt->nextbranch;
+                else
+                    pre->nextbranch = pt->nextbranch;
+            }
+	else {
+	    if (!cuttail && !quietflag) {
+		if (!yesorno(false, "Do you really want to delete all revisions? [ny](n): ")) {
+		    rcserror("No revision deleted");
+		    Delta = delstrt;
+		    while( Delta) {
+			Delta->selector = true;
+			Delta = Delta->next;
+		    }
+		    return;
+		}
+	    }
+            Head = cuttail;
+	}
+        return;
+}
+
+#if RCS_lint
+/* This lets us lint everything all at once. */
+
+char const cmdid[] = "";
+
+#define go(p,e) {int p P((int,char**)); void e P((void)); if(*argv)return p(argc,argv);if(*argv[1])e();}
+
+	int
+main(argc, argv)
+	int argc;
+	char **argv;
+{
+	go(ciId,	ciExit);
+	go(coId,	coExit);
+	go(identId,	identExit);
+	go(mergeId,	mergeExit);
+	go(rcsId,	exiterr);
+	go(rcscleanId,	rcscleanExit);
+	go(rcsdiffId,	rdiffExit);
+	go(rcsmergeId,	rmergeExit);
+	go(rlogId,	rlogExit);
+	return 0;
+}
+#endif
diff --git a/gnu/usr.bin/rcs/rcs/rcsfile.5 b/gnu/usr.bin/rcs/rcs/rcsfile.5
new file mode 100644
index 0000000000000..0d8aac874d45c
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcs/rcsfile.5
@@ -0,0 +1,425 @@
+.lf 1 ./rcsfile.5in
+.\" Set p to 1 if your formatter can handle pic output.
+.if t .nr p 1
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH RCSFILE 5 \*(Dt GNU
+.SH NAME
+rcsfile \- format of RCS file
+.SH DESCRIPTION
+An \*r file's
+contents are described by the grammar
+below.
+.PP
+The text is free format: space, backspace, tab, newline, vertical
+tab, form feed, and carriage return (collectively,
+.IR "white space")
+have no significance except in strings.
+However, white space cannot appear within an id, num, or sym,
+and an \*r file must end with a newline.
+.PP
+Strings are enclosed by
+.BR @ .
+If a string contains a
+.BR @ ,
+it must be doubled;
+otherwise, strings can contain arbitrary binary data.
+.PP
+The meta syntax uses the following conventions: `|' (bar) separates
+alternatives; `{' and `}' enclose optional phrases; `{' and `}*' enclose
+phrases that can be repeated zero or more times;
+`{' and '}+' enclose phrases that must appear at least once and can be
+repeated;
+Terminal symbols are in
+.BR boldface ;
+nonterminal symbols are in
+.IR italics .
+.LP
+.nr w \w'\f3deltatext\fP '
+.nr y \w'\f3newphrase\fP '
+.if \nw<\ny .nr w \ny
+.nr x \w'\f3branches\fP'
+.nr y \w'{ \f3comment\fP'
+.if \nx<\ny .nr x \ny
+.nr y \w'\f3{ branch\fP'
+.if \nx<\ny .nr x \ny
+.ta \nwu +\w'::=  'u +\nxu+\w'  'u
+.fc #
+.nf
+\f2rcstext\fP	::=	\f2admin\fP {\f2delta\fP}* \f2desc\fP {\f2deltatext\fP}*
+.LP
+\f2admin\fP	::=	\f3head\fP	{\f2num\fP}\f3;\fP
+		{ \f3branch\fP	{\f2num\fP}\f3;\fP }
+		\f3access\fP	{\f2id\fP}*\f3;\fP
+		\f3symbols\fP	{\f2sym\fP \f3:\fP \f2num\fP}*\f3;\fP
+		\f3locks\fP	{\f2id\fP \f3:\fP \f2num\fP}*\f3;\fP  {\f3strict  ;\fP}
+		{ \f3comment\fP	{\f2string\fP}\f3;\fP }
+		{ \f3expand\fP	{\f2string\fP}\f3;\fP }
+		{ \f2newphrase\fP }*
+.LP
+\f2delta\fP	::=	\f2num\fP
+		\f3date\fP	\f2num\fP\f3;\fP
+		\f3author\fP	\f2id\fP\f3;\fP
+		\f3state\fP	{\f2id\fP}\f3;\fP
+		\f3branches\fP	{\f2num\fP}*\f3;\fP
+		\f3next\fP	{\f2num\fP}\f3;\fP
+		{ \f2newphrase\fP }*
+.LP
+\f2desc\fP	::=	\f3desc\fP	\f2string\fP
+.LP
+\f2deltatext\fP	::=	\f2num\fP
+		\f3log\fP	\f2string\fP
+		{ \f2newphrase\fP }*
+		\f3text\fP	\f2string\fP
+.LP
+\f2num\fP	::=	{\f2digit\fP | \f3.\fP}+
+.LP
+\f2digit\fP	::=	\f30\fP | \f31\fP | \f32\fP | \f33\fP | \f34\fP | \f35\fP | \f36\fP | \f37\fP | \f38\fP | \f39\fP
+.LP
+\f2id\fP	::=	{\f2num\fP} \f2idchar\fP {\f2idchar\fP | \f2num\fP}*
+.LP
+\f2sym\fP	::=	{\f2digit\fP}* \f2idchar\fP {\f2idchar\fP | \f2digit\fP}*
+.LP
+\f2idchar\fP	::=	any visible graphic character except \f2special\fP
+.LP
+\f2special\fP	::=	\f3$\fP | \f3,\fP | \f3.\fP | \f3:\fP | \f3;\fP | \f3@\fP
+.LP
+\f2string\fP	::=	\f3@\fP{any character, with \f3@\fP doubled}*\f3@\fP
+.LP
+\f2newphrase\fP	::=	\f2id\fP \f2word\fP* \f3;\fP
+.LP
+\f2word\fP	::=	\f2id\fP | \f2num\fP | \f2string\fP | \f3:\fP
+.fi
+.PP
+Identifiers are case sensitive.  Keywords are in lower case only.
+The sets of keywords and identifiers can overlap.
+In most environments \*r uses the \s-1ISO\s0 8859/1 encoding:
+visible graphic characters are codes 041\-176 and 240\-377,
+and white space characters are codes 010\-015 and 040.
+.PP
+Dates, which appear after the
+.B date
+keyword, are of the form
+\f2Y\fP\f3.\fP\f2mm\fP\f3.\fP\f2dd\fP\f3.\fP\f2hh\fP\f3.\fP\f2mm\fP\f3.\fP\f2ss\fP,
+where
+.I Y
+is the year,
+.I mm
+the month (01\-12),
+.I dd
+the day (01\-31),
+.I hh
+the hour (00\-23),
+.I mm
+the minute (00\-59),
+and
+.I ss
+the second (00\-60).
+.I Y
+contains just the last two digits of the year
+for years from 1900 through 1999,
+and all the digits of years thereafter.
+Dates use the Gregorian calendar; times use UTC.
+.PP
+The
+.I newphrase
+productions in the grammar are reserved for future extensions
+to the format of \*r files.
+No
+.I newphrase
+will begin with any keyword already in use.
+.PP
+The
+.I delta
+nodes form a tree.  All nodes whose numbers
+consist of a single pair
+(e.g., 2.3, 2.1, 1.3, etc.)
+are on the trunk, and are linked through the
+.B next
+field in order of decreasing numbers.
+The
+.B head
+field in the
+.I admin
+node points to the head of that sequence (i.e., contains
+the highest pair).
+The
+.B branch
+node in the admin node indicates the default
+branch (or revision) for most \*r operations.
+If empty, the default
+branch is the highest branch on the trunk.
+.PP
+All
+.I delta
+nodes whose numbers consist of
+.RI 2 n
+fields
+.RI ( n \(>=2)
+(e.g., 3.1.1.1, 2.1.2.2, etc.)
+are linked as follows.
+All nodes whose first
+.RI 2 n \-1
+number fields are identical are linked through the
+.B next
+field in order of increasing numbers.
+For each such sequence,
+the
+.I delta
+node whose number is identical to the first
+.RI 2 n \-2
+number fields of the deltas on that sequence is called the branchpoint.
+The
+.B branches
+field of a node contains a list of the
+numbers of the first nodes of all sequences for which it is a branchpoint.
+This list is ordered in increasing numbers.
+.LP
+The following diagram shows an example of an \*r file's organization.
+.if !\np \{\
+.nf
+.vs 12
+.ne 36
+.cs 1 20
+.eo
+
+                           Head
+                             |
+                             |
+                             v                        / \
+                         ---------                   /   \
+   / \          / \      |       |      / \         /     \
+  /   \        /   \     |  2.1  |     /   \       /       \
+ /     \      /     \    |       |    /     \     /         \
+/1.2.1.3\    /1.3.1.1\   |       |   /1.2.2.2\   /1.2.2.1.1.1\
+---------    ---------   ---------   ---------   -------------
+    ^            ^           |           ^             ^
+    |            |           |           |             |
+    |            |           v           |             |
+   / \           |       ---------      / \            |
+  /   \          |       \  1.3  /     /   \           |
+ /     \         ---------\     /     /     \-----------
+/1.2.1.1\                  \   /     /1.2.2.1\
+---------                   \ /      ---------
+    ^                        |           ^
+    |                        |           |
+    |                        v           |
+    |                    ---------       |
+    |                    \  1.2  /       |
+    ----------------------\     /---------
+                           \   /
+                            \ /
+                             |
+                             |
+                             v
+                         ---------
+                         \  1.1  /
+                          \     /
+                           \   /
+                            \ /
+
+.ec
+.cs 1
+.vs
+.fi
+.\}
+.if \np \{\
+.lf 232
+.PS 4.250i 3.812i
+.\" -2.0625 -4.25 1.75 0
+.\" 0.000i 4.250i 3.812i 0.000i
+.nr 00 \n(.u
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+.sp -1
+.lf 252
+\h'2.062i-(\w'1.2'u/2u)'\v'3.000i-(1v/2u)+0v+0.22m'1.2
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+.sp -1
+\h'0.000i'\v'1.500i'\D'l0.750i 0.000i'
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+\h'0.750i'\v'1.500i'\D'l-0.375i -0.500i'
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+\h'2.725i'\v'2.600i'\D'l0.025i -0.100i'
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+.lf 261
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+\h'2.375i'\v'2.500i'\D'l0.750i 0.000i'
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+\h'3.125i'\v'2.500i'\D'l-0.375i -0.500i'
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+\h'2.938i'\v'2.250i'\D'~0.500i 0.000i 0.000i -0.500i 0.000i -0.500i'
+.sp -1
+\h'3.413i'\v'1.350i'\D'l0.025i -0.100i'
+.sp -1
+\h'3.438i'\v'1.250i'\D'l0.025i 0.100i'
+.sp -1
+.lf 264
+\h'3.438i-(\w'\s-21.2.2.1.1.1\s0'u/2u)'\v'1.000i-(1v/2u)+1v+0.22m'\s-21.2.2.1.1.1\s0
+.sp -1
+\h'3.438i'\v'0.750i'\D'l-0.375i 0.500i'
+.sp -1
+\h'3.062i'\v'1.250i'\D'l0.750i 0.000i'
+.sp -1
+\h'3.812i'\v'1.250i'\D'l-0.375i -0.500i'
+.sp -1
+\h'2.750i'\v'2.000i'\D'l0.000i -0.500i'
+.sp -1
+\h'2.725i'\v'1.600i'\D'l0.025i -0.100i'
+.sp -1
+\h'2.750i'\v'1.500i'\D'l0.025i 0.100i'
+.sp -1
+.lf 267
+\h'2.750i-(\w'1.2.2.2'u/2u)'\v'1.250i-(1v/2u)+1v+0.22m'1.2.2.2
+.sp -1
+\h'2.750i'\v'1.000i'\D'l-0.375i 0.500i'
+.sp -1
+\h'2.375i'\v'1.500i'\D'l0.750i 0.000i'
+.sp -1
+\h'3.125i'\v'1.500i'\D'l-0.375i -0.500i'
+.sp -1
+\h'2.062i'\v'3.250i'\D'l0.000i 0.500i'
+.sp -1
+\h'2.087i'\v'3.650i'\D'l-0.025i 0.100i'
+.sp -1
+\h'2.062i'\v'3.750i'\D'l-0.025i -0.100i'
+.sp -1
+.lf 270
+\h'2.062i-(\w'1.1'u/2u)'\v'4.000i-(1v/2u)+0v+0.22m'1.1
+.sp -1
+\h'2.062i'\v'4.250i'\D'l-0.375i -0.500i'
+.sp -1
+\h'1.688i'\v'3.750i'\D'l0.750i 0.000i'
+.sp -1
+\h'2.438i'\v'3.750i'\D'l-0.375i 0.500i'
+.sp -1
+.sp 4.250i+1
+.if \n(00 .fi
+.br
+.nr 0x 0
+.lf 271
+.PE
+.lf 272
+.\}
+.SH IDENTIFICATION
+.de VL
+\\$2
+..
+Author: Walter F. Tichy,
+Purdue University, West Lafayette, IN, 47907.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH SEE ALSO
+rcsintro(1), ci(1), co(1), ident(1), rcs(1), rcsclean(1), rcsdiff(1),
+rcsmerge(1), rlog(1)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
diff --git a/gnu/usr.bin/rcs/rcs/rcsintro.1 b/gnu/usr.bin/rcs/rcs/rcsintro.1
new file mode 100644
index 0000000000000..edcd9ee9389d1
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcs/rcsintro.1
@@ -0,0 +1,302 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.if !\n(.g \{\
+.	if !\w|\*(lq| \{\
+.		ds lq ``
+.		if \w'\(lq' .ds lq "\(lq
+.	\}
+.	if !\w|\*(rq| \{\
+.		ds rq ''
+.		if \w'\(rq' .ds rq "\(rq
+.	\}
+.\}
+.am SS
+.LP
+..
+.TH RCSINTRO 1 \*(Dt GNU
+.SH NAME
+rcsintro \- introduction to RCS commands
+.SH DESCRIPTION
+The Revision Control System (\*r) manages multiple revisions of files.
+\*r automates the storing, retrieval, logging, identification, and merging
+of revisions.  \*r is useful for text that is revised frequently, for example
+programs, documentation, graphics, papers, and form letters.
+.PP
+The basic user interface is extremely simple.  The novice only needs
+to learn two commands:
+.BR ci (1)
+and
+.BR co (1).
+.BR ci ,
+short for \*(lqcheck in\*(rq, deposits the contents of a
+file into an archival file called an \*r file.  An \*r file
+contains all revisions of a particular file.
+.BR co ,
+short for \*(lqcheck out\*(rq, retrieves revisions from an \*r file.
+.SS "Functions of \*r"
+.IP \(bu
+Store and retrieve multiple revisions of text.  \*r saves all old
+revisions in a space efficient way.
+Changes no longer destroy the original, because the
+previous revisions remain accessible.  Revisions can be retrieved according to
+ranges of revision numbers, symbolic names, dates, authors, and
+states.
+.IP \(bu
+Maintain a complete history of changes.
+\*r logs all changes automatically.
+Besides the text of each revision, \*r stores the author, the date and time of
+check-in, and a log message summarizing the change.
+The logging makes it easy to find out
+what happened to a module, without having to compare
+source listings or having to track down colleagues.
+.IP \(bu
+Resolve access conflicts.  When two or more programmers wish to
+modify the same revision, \*r alerts the programmers and prevents one
+modification from corrupting the other.
+.IP \(bu
+Maintain a tree of revisions.  \*r can maintain separate lines of development
+for each module.  It stores a tree structure that represents the
+ancestral relationships among revisions.
+.IP \(bu
+Merge revisions and resolve conflicts.
+Two separate lines of development of a module can be coalesced by merging.
+If the revisions to be merged affect the same sections of code, \*r alerts the
+user about the overlapping changes.
+.IP \(bu
+Control releases and configurations.
+Revisions can be assigned symbolic names
+and marked as released, stable, experimental, etc.
+With these facilities, configurations of modules can be
+described simply and directly.
+.IP \(bu
+Automatically identify each revision with name, revision number,
+creation time, author, etc.
+The identification is like a stamp that can be embedded at an appropriate place
+in the text of a revision.
+The identification makes it simple to determine which
+revisions of which modules make up a given configuration.
+.IP \(bu
+Minimize secondary storage.  \*r needs little extra space for
+the revisions (only the differences).  If intermediate revisions are
+deleted, the corresponding deltas are compressed accordingly.
+.SS "Getting Started with \*r"
+Suppose you have a file
+.B f.c
+that you wish to put under control of \*r.
+If you have not already done so, make an \*r directory with the command
+.IP
+.B "mkdir  RCS"
+.LP
+Then invoke the check-in command
+.IP
+.B "ci  f.c"
+.LP
+This command creates an \*r file in the
+.B RCS
+directory,
+stores
+.B f.c
+into it as revision 1.1, and
+deletes
+.BR f.c .
+It also asks you for a description.  The description
+should be a synopsis of the contents of the file.  All later check-in
+commands will ask you for a log entry, which should summarize the
+changes that you made.
+.PP
+Files in the \*r directory are called \*r files;
+the others are called working files.
+To get back the working file
+.B f.c
+in the previous example, use the check-out
+command
+.IP
+.B "co  f.c"
+.LP
+This command extracts the latest revision from the \*r file
+and writes
+it into
+.BR f.c .
+If you want to edit
+.BR f.c ,
+you must lock it as you check it out with the command
+.IP
+.B "co  \-l  f.c"
+.LP
+You can now edit
+.BR f.c .
+.PP
+Suppose after some editing you want to know what changes that you have made.
+The command
+.IP
+.B "rcsdiff  f.c"
+.LP
+tells you the difference between the most recently checked-in version
+and the working file.
+You can check the file back in by invoking
+.IP
+.B "ci  f.c"
+.LP
+This increments the revision number properly.
+.PP
+If
+.B ci
+complains with the message
+.IP
+.BI "ci error: no lock set by " "your name"
+.LP
+then you have tried to check in a file even though you did not
+lock it when you checked it out.
+Of course, it is too late now to do the check-out with locking, because
+another check-out would
+overwrite your modifications.  Instead, invoke
+.IP
+.B "rcs  \-l  f.c"
+.LP
+This command will lock the latest revision for you, unless somebody
+else got ahead of you already.  In this case, you'll have to negotiate with
+that person.
+.PP
+Locking assures that you, and only you, can check in the next update, and
+avoids nasty problems if several people work on the same file.
+Even if a revision is locked, it can still be checked out for
+reading, compiling, etc.  All that locking
+prevents is a
+.I "check-in"
+by anybody but the locker.
+.PP
+If your \*r file is private, i.e., if you are the only person who is going
+to deposit revisions into it, strict locking is not needed and you
+can turn it off.
+If strict locking is turned off,
+the owner of the \*r file need not have a lock for check-in; all others
+still do.  Turning strict locking off and on is done with the commands
+.IP
+.BR "rcs  \-U  f.c" "     and     " "rcs  \-L  f.c"
+.LP
+If you don't want to clutter your working directory with \*r files, create
+a subdirectory called
+.B RCS
+in your working directory, and move all your \*r
+files there.  \*r commands will look first into that directory to find
+needed files.  All the commands discussed above will still work, without any
+modification.
+(Actually, pairs of \*r and working files can be specified in three ways:
+(a) both are given, (b) only the working file is given, (c) only the
+\*r file is given.  Both \*r and working files may have arbitrary path prefixes;
+\*r commands pair them up intelligently.)
+.PP
+To avoid the deletion of the working file during check-in (in case you want to
+continue editing or compiling), invoke
+.IP
+.BR "ci  \-l  f.c" "     or     " "ci  \-u  f.c"
+.LP
+These commands check in
+.B f.c
+as usual, but perform an implicit
+check-out.  The first form also locks the checked in revision, the second one
+doesn't.  Thus, these options save you one check-out operation.
+The first form is useful if you want to continue editing,
+the second one if you just want to read the file.
+Both update the identification markers in your working file (see below).
+.PP
+You can give
+.B ci
+the number you want assigned to a checked in
+revision.  Assume all your revisions were numbered 1.1, 1.2, 1.3, etc.,
+and you would like to start release 2.
+The command
+.IP
+.BR "ci  \-r2  f.c" "     or     " "ci  \-r2.1  f.c"
+.LP
+assigns the number 2.1 to the new revision.
+From then on,
+.B ci
+will number the subsequent revisions
+with 2.2, 2.3, etc.  The corresponding
+.B co
+commands
+.IP
+.BR "co  \-r2  f.c" "     and     " "co  \-r2.1  f.c"
+.PP
+retrieve the latest revision numbered
+.RI 2. x
+and the revision 2.1,
+respectively.
+.B co
+without a revision number selects
+the latest revision on the
+.IR trunk ,
+i.e. the highest
+revision with a number consisting of two fields.  Numbers with more than two
+fields are needed for branches.
+For example, to start a branch at revision 1.3, invoke
+.IP
+.B "ci  \-r1.3.1  f.c"
+.LP
+This command starts a branch numbered 1 at revision 1.3, and assigns
+the number 1.3.1.1 to the new revision.  For more information about
+branches, see
+.BR rcsfile (5).
+.SS "Automatic Identification"
+\*r can put special strings for identification into your source and object
+code.  To obtain such identification, place the marker
+.IP
+.B "$\&Id$"
+.LP
+into your text, for instance inside a comment.
+\*r will replace this marker with a string of the form
+.IP
+.BI $\&Id: "  filename  revision  date  time  author  state  " $
+.LP
+With such a marker on the first page of each module, you can
+always see with which revision you are working.
+\*r keeps the markers up to date automatically.
+To propagate the markers into your object code, simply put
+them into literal character strings.  In C, this is done as follows:
+.IP
+.ft 3
+static char rcsid[] = \&"$\&Id$\&";
+.ft
+.LP
+The command
+.B ident
+extracts such markers from any file, even object code
+and dumps.
+Thus,
+.B ident
+lets you find out
+which revisions of which modules were used in a given program.
+.PP
+You may also find it useful to put the marker
+.B $\&Log$
+into your text, inside a comment.  This marker accumulates
+the log messages that are requested during check-in.
+Thus, you can maintain the complete history of your file directly inside it.
+There are several additional identification markers; see
+.BR co (1)
+for
+details.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), ident(1), rcs(1), rcsdiff(1), rcsintro(1), rcsmerge(1), rlog(1)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.br
diff --git a/gnu/usr.bin/rcs/rcsclean/Makefile b/gnu/usr.bin/rcs/rcsclean/Makefile
new file mode 100644
index 0000000000000..fe538a0a41f16
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsclean/Makefile
@@ -0,0 +1,8 @@
+PROG=	rcsclean
+SRCS=	rcsclean.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=	${LIBRCS}
+DPADD=	${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rcsclean/rcsclean.1 b/gnu/usr.bin/rcs/rcsclean/rcsclean.1
new file mode 100644
index 0000000000000..3111915455a68
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsclean/rcsclean.1
@@ -0,0 +1,203 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH RCSCLEAN 1 \*(Dt GNU
+.SH NAME
+rcsclean \- clean up working files
+.SH SYNOPSIS
+.B rcsclean
+.RI [ options "] [ " file " .\|.\|. ]"
+.SH DESCRIPTION
+.B rcsclean
+removes files that are not being worked on.
+.B "rcsclean \-u"
+also unlocks and removes files that are being worked on
+but have not changed.
+.PP
+For each
+.I file
+given,
+.B rcsclean
+compares the working file and a revision in the corresponding
+\*r file.  If it finds a difference, it does nothing.
+Otherwise, it first unlocks the revision if the
+.B \-u
+option is given,
+and then removes the working file
+unless the working file is writable and the revision is locked.
+It logs its actions by outputting the corresponding
+.B "rcs \-u"
+and
+.B "rm \-f"
+commands on the standard output.
+.PP
+Files are paired as explained in
+.BR ci (1).
+If no
+.I file
+is given, all working files in the current directory are cleaned.
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+.PP
+The number of the revision to which the working file is compared
+may be attached to any of the options
+.BR \-n ,
+.BR \-q ,
+.BR \-r ,
+or
+.BR \-u .
+If no revision number is specified, then if the
+.B \-u
+option is given and the caller has one revision locked,
+.B rcsclean
+uses that revision; otherwise
+.B rcsclean
+uses the latest revision on the default branch, normally the root.
+.PP
+.B rcsclean
+is useful for
+.B clean
+targets in makefiles.
+See also
+.BR rcsdiff (1),
+which prints out the differences,
+and
+.BR ci (1),
+which
+normally reverts to the previous revision
+if a file was not changed.
+.SH OPTIONS
+.TP
+.BI \-k subst
+Use
+.I subst
+style keyword substitution when retrieving the revision for comparison.
+See
+.BR co (1)
+for details.
+.TP
+.BR \-n [\f2rev\fP]
+Do not actually remove any files or unlock any revisions.
+Using this option will tell you what
+.B rcsclean
+would do without actually doing it.
+.TP
+.BR \-q [\f2rev\fP]
+Do not log the actions taken on standard output.
+.TP
+.BR \-r [\f2rev\fP]
+This option has no effect other than specifying the revision for comparison.
+.TP
+.B \-T
+Preserve the modification time on the \*r file
+even if the \*r file changes because a lock is removed.
+This option can suppress extensive recompilation caused by a
+.BR make (1)
+dependency of some other copy of the working file on the \*r file.
+Use this option with care; it can suppress recompilation even when it is needed,
+i.e. when the lock removal
+would mean a change to keyword strings in the other working file.
+.TP
+.BR \-u [\f2rev\fP]
+Unlock the revision if it is locked and no difference is found.
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.IR n .
+See
+.BR co (1)
+for details.
+.TP
+.BI \-x "suffixes"
+Use
+.I suffixes
+to characterize \*r files.
+See
+.BR ci (1)
+for details.
+.TP
+.BI \-z zone
+Use
+.I zone
+as the time zone for keyword substitution;
+see
+.BR co (1)
+for details.
+.SH EXAMPLES
+.LP
+.RS
+.ft 3
+rcsclean  *.c  *.h
+.ft
+.RE
+.LP
+removes all working files ending in
+.B .c
+or
+.B .h
+that were not changed
+since their checkout.
+.LP
+.RS
+.ft 3
+rcsclean
+.ft
+.RE
+.LP
+removes all working files in the current directory
+that were not changed since their checkout.
+.SH FILES
+.B rcsclean
+accesses files much as
+.BR ci (1)
+does.
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+A backslash escapes spaces within an option.
+The
+.B \s-1RCSINIT\s0
+options are prepended to the argument lists of most \*r commands.
+Useful
+.B \s-1RCSINIT\s0
+options include
+.BR \-q ,
+.BR \-V ,
+.BR \-x ,
+and
+.BR \-z .
+.SH DIAGNOSTICS
+The exit status is zero if and only if all operations were successful.
+Missing working files and \*r files are silently ignored.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), ident(1), rcs(1), rcsdiff(1), rcsintro(1), rcsmerge(1), rlog(1),
+rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.SH BUGS
+At least one
+.I file
+must be given in older Unix versions that
+do not provide the needed directory scanning operations.
+.br
diff --git a/gnu/usr.bin/rcs/rcsclean/rcsclean.c b/gnu/usr.bin/rcs/rcsclean/rcsclean.c
new file mode 100644
index 0000000000000..32c8e7dfbc63f
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsclean/rcsclean.c
@@ -0,0 +1,333 @@
+/* Clean up working files.  */
+
+/* Copyright 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+	rcs-bugs@cs.purdue.edu
+
+*/
+
+#include "rcsbase.h"
+
+#if has_dirent
+	static int get_directory P((char const*,char***));
+#endif
+
+static int unlock P((struct hshentry *));
+static void cleanup P((void));
+
+static RILE *workptr;
+static int exitstatus;
+
+mainProg(rcscleanId, "rcsclean", "$FreeBSD$")
+{
+	static char const usage[] =
+		"\nrcsclean: usage: rcsclean -ksubst -{nqru}[rev] -T -Vn -xsuff -zzone file ...";
+
+	static struct buf revision;
+
+	char *a, **newargv;
+	char const *rev, *p;
+	int dounlock, expmode, perform, unlocked, unlockflag, waslocked;
+	int Ttimeflag;
+	struct hshentries *deltas;
+	struct hshentry *delta;
+	struct stat workstat;
+
+	setrid();
+
+	expmode = -1;
+	rev = 0;
+	suffixes = X_DEFAULT;
+	perform = true;
+	unlockflag = false;
+	Ttimeflag = false;
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	for (;;) {
+		if (--argc < 1) {
+#			if has_dirent
+				argc = get_directory(".", &newargv);
+				argv = newargv;
+				break;
+#			else
+				faterror("no pathnames specified");
+#			endif
+		}
+		a = *++argv;
+		if (!*a  ||  *a++ != '-')
+			break;
+		switch (*a++) {
+			case 'k':
+				if (0 <= expmode)
+					redefined('k');
+				if ((expmode = str2expmode(a))  <  0)
+					goto unknown;
+				break;
+
+			case 'n':
+				perform = false;
+				goto handle_revision;
+
+			case 'q':
+				quietflag = true;
+				/* fall into */
+			case 'r':
+			handle_revision:
+				if (*a) {
+					if (rev)
+						warn("redefinition of revision number");
+					rev = a;
+				}
+				break;
+
+			case 'T':
+				if (*a)
+					goto unknown;
+				Ttimeflag = true;
+				break;
+
+			case 'u':
+				unlockflag = true;
+				goto handle_revision;
+
+			case 'V':
+				setRCSversion(*argv);
+				break;
+
+			case 'x':
+				suffixes = a;
+				break;
+
+			case 'z':
+				zone_set(a);
+				break;
+
+			default:
+			unknown:
+				error("unknown option: %s%s", *argv, usage);
+		}
+	}
+
+	dounlock = perform & unlockflag;
+
+	if (nerror)
+	  cleanup();
+	else
+	  for (;  0 < argc;  cleanup(), ++argv, --argc) {
+
+		ffree();
+
+		if (!(
+			0 < pairnames(
+				argc, argv,
+				dounlock ? rcswriteopen : rcsreadopen,
+				true, true
+			) &&
+			(workptr = Iopen(workname, FOPEN_R_WORK, &workstat))
+		))
+			continue;
+
+		if (same_file(RCSstat, workstat, 0)) {
+			rcserror("RCS file is the same as working file %s.",
+				workname
+			);
+			continue;
+		}
+
+		gettree();
+
+		p = 0;
+		if (rev) {
+			if (!fexpandsym(rev, &revision, workptr))
+				continue;
+			p = revision.string;
+		} else if (Head)
+			switch (unlockflag ? findlock(false,&delta) : 0) {
+				default:
+					continue;
+				case 0:
+					p = Dbranch ? Dbranch : "";
+					break;
+				case 1:
+					p = delta->num;
+					break;
+			}
+		delta = 0;
+		deltas = 0;  /* Keep lint happy.  */
+		if (p  &&  !(delta = genrevs(p,(char*)0,(char*)0,(char*)0,&deltas)))
+			continue;
+
+		waslocked = delta && delta->lockedby;
+		locker_expansion = unlock(delta);
+		unlocked = locker_expansion & unlockflag;
+		if (unlocked<waslocked  &&  workstat.st_mode&(S_IWUSR|S_IWGRP|S_IWOTH))
+			continue;
+
+		if (unlocked && !checkaccesslist())
+			continue;
+
+		if (dorewrite(dounlock, unlocked) != 0)
+			continue;
+
+		if (0 <= expmode)
+			Expand = expmode;
+		else if (
+			waslocked  &&
+			Expand == KEYVAL_EXPAND  &&
+			WORKMODE(RCSstat.st_mode,true) == workstat.st_mode
+		)
+			Expand = KEYVALLOCK_EXPAND;
+
+		getdesc(false);
+
+		if (
+			!delta ? workstat.st_size!=0 :
+			0 < rcsfcmp(
+				workptr, &workstat,
+				buildrevision(deltas, delta, (FILE*)0, false),
+				delta
+			)
+		)
+			continue;
+
+		if (quietflag < unlocked)
+			aprintf(stdout, "rcs -u%s %s\n", delta->num, RCSname);
+
+		if (perform & unlocked) {
+			if_advise_access(deltas->first != delta, finptr, MADV_SEQUENTIAL);
+			if (donerewrite(true,
+				Ttimeflag ? RCSstat.st_mtime : (time_t)-1
+			) != 0)
+				continue;
+		}
+
+		if (!quietflag)
+			aprintf(stdout, "rm -f %s\n", workname);
+		Izclose(&workptr);
+		if (perform  &&  un_link(workname) != 0)
+			eerror(workname);
+
+	  }
+
+	tempunlink();
+	if (!quietflag)
+		Ofclose(stdout);
+	exitmain(exitstatus);
+}
+
+	static void
+cleanup()
+{
+	if (nerror) exitstatus = EXIT_FAILURE;
+	Izclose(&finptr);
+	Izclose(&workptr);
+	Ozclose(&fcopy);
+	ORCSclose();
+	dirtempunlink();
+}
+
+#if RCS_lint
+#	define exiterr rcscleanExit
+#endif
+	void
+exiterr()
+{
+	ORCSerror();
+	dirtempunlink();
+	tempunlink();
+	_exit(EXIT_FAILURE);
+}
+
+	static int
+unlock(delta)
+	struct hshentry *delta;
+{
+	register struct rcslock **al, *l;
+
+	if (delta && delta->lockedby && strcmp(getcaller(),delta->lockedby)==0)
+		for (al = &Locks;  (l = *al);  al = &l->nextlock)
+			if (l->delta == delta) {
+				*al = l->nextlock;
+				delta->lockedby = 0;
+				return true;
+			}
+	return false;
+}
+
+#if has_dirent
+	static int
+get_directory(dirname, aargv)
+	char const *dirname;
+	char ***aargv;
+/*
+ * Put a vector of all DIRNAME's directory entries names into *AARGV.
+ * Ignore names of RCS files.
+ * Yield the number of entries found.  Terminate the vector with 0.
+ * Allocate the storage for the vector and entry names.
+ * Do not sort the names.  Do not include '.' and '..'.
+ */
+{
+	int i, entries = 0, entries_max = 64;
+	size_t chars = 0, chars_max = 1024;
+	size_t *offset = tnalloc(size_t, entries_max);
+	char *a = tnalloc(char, chars_max), **p;
+	DIR *d;
+	struct dirent *e;
+
+	if (!(d = opendir(dirname)))
+		efaterror(dirname);
+	while ((errno = 0,  e = readdir(d))) {
+		char const *en = e->d_name;
+		size_t s = strlen(en) + 1;
+		if (en[0]=='.'   &&   (!en[1]  ||  (en[1]=='.' && !en[2])))
+			continue;
+		if (rcssuffix(en))
+			continue;
+		while (chars_max < s + chars)
+			a = trealloc(char, a, chars_max<<=1);
+		if (entries == entries_max)
+			offset = trealloc(size_t, offset, entries_max<<=1);
+		offset[entries++] = chars;
+		VOID strcpy(a+chars, en);
+		chars += s;
+	}
+#	if void_closedir
+#		define close_directory(d) (closedir(d), 0)
+#	else
+#		define close_directory(d) closedir(d)
+#	endif
+	if (errno  ||  close_directory(d) != 0)
+		efaterror(dirname);
+	if (chars)
+		a = trealloc(char, a, chars);
+	else
+		tfree(a);
+	*aargv = p = tnalloc(char*, entries+1);
+	for (i=0; i<entries; i++)
+		*p++ = a + offset[i];
+	*p = 0;
+	tfree(offset);
+	return entries;
+}
+#endif
diff --git a/gnu/usr.bin/rcs/rcsdiff/Makefile b/gnu/usr.bin/rcs/rcsdiff/Makefile
new file mode 100644
index 0000000000000..45ce23fbf60f5
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsdiff/Makefile
@@ -0,0 +1,8 @@
+PROG=	rcsdiff
+SRCS=	rcsdiff.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=  ${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rcsdiff/rcsdiff.1 b/gnu/usr.bin/rcs/rcsdiff/rcsdiff.1
new file mode 100644
index 0000000000000..74117c270e6c3
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsdiff/rcsdiff.1
@@ -0,0 +1,158 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH RCSDIFF 1 \*(Dt GNU
+.SH NAME
+rcsdiff \- compare RCS revisions
+.SH SYNOPSIS
+.B rcsdiff
+[
+.BI \-k subst
+] [
+.B \-q
+] [
+.BI \-r rev1
+[
+.BI \-r rev2
+] ] [
+.B \-T
+] [
+.RI "\f3\-V\fP[" n ]
+] [
+.BI \-x suffixes
+] [
+.BI \-z zone
+] [
+.I "diff options"
+]
+.I "file .\|.\|."
+.SH DESCRIPTION
+.B rcsdiff
+runs
+.BR diff (1)
+to compare two revisions of each \*r file given.
+.PP
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+Names are paired as explained in
+.BR ci (1).
+.PP
+The option
+.B \-q
+suppresses diagnostic output.
+Zero, one, or two revisions may be specified with
+.BR \-r .
+The option
+.BI \-k subst
+affects keyword substitution when extracting
+revisions, as described in
+.BR co (1);
+for example,
+.B "\-kk\ \-r1.1\ \-r1.2"
+ignores differences in keyword values when comparing revisions
+.B 1.1
+and
+.BR 1.2 .
+To avoid excess output from locker name substitution,
+.B \-kkvl
+is assumed if (1) at most one revision option is given,
+(2) no
+.B \-k
+option is given, (3)
+.B \-kkv
+is the default keyword substitution, and
+(4) the working file's mode would be produced by
+.BR "co\ \-l".
+See
+.BR co (1)
+for details
+about
+.BR \-T ,
+.BR \-V ,
+.B \-x
+and
+.BR \-z .
+Otherwise, all options of
+.BR diff (1)
+that apply to regular files are accepted, with the same meaning as for
+.BR diff .
+.PP
+If both
+.I rev1
+and
+.I rev2
+are omitted,
+.B rcsdiff
+compares the latest revision on the
+default branch (by default the trunk)
+with the contents of the corresponding working file.  This is useful
+for determining what you changed since the last checkin.
+.PP
+If
+.I rev1
+is given, but
+.I rev2
+is omitted,
+.B rcsdiff
+compares revision
+.I rev1
+of the \*r file with
+the contents of the corresponding working file.
+.PP
+If both
+.I rev1
+and
+.I rev2
+are given,
+.B rcsdiff
+compares revisions
+.I rev1
+and
+.I rev2
+of the \*r file.
+.PP
+Both
+.I rev1
+and
+.I rev2
+may be given numerically or symbolically.
+.SH EXAMPLE
+The command
+.LP
+.B "        rcsdiff  f.c"
+.LP
+compares the latest revision on the default branch of the \*r file
+to the contents of the working file
+.BR f.c .
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+See
+.BR ci (1)
+for details.
+.SH DIAGNOSTICS
+Exit status is 0 for no differences during any comparison,
+1 for some differences, 2 for trouble.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), diff(1), ident(1), rcs(1), rcsintro(1), rcsmerge(1), rlog(1)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.br
diff --git a/gnu/usr.bin/rcs/rcsdiff/rcsdiff.c b/gnu/usr.bin/rcs/rcsdiff/rcsdiff.c
new file mode 100644
index 0000000000000..7d3c0a37f66a6
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsdiff/rcsdiff.c
@@ -0,0 +1,480 @@
+/* Compare RCS revisions.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.19  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.18  1995/06/01 16:23:43  eggert
+ * (main): Pass "--binary" if -kb and if --binary makes a difference.
+ * Don't treat + options specially.
+ *
+ * Revision 5.17  1994/03/17 14:05:48  eggert
+ * Specify subprocess input via file descriptor, not file name.  Remove lint.
+ *
+ * Revision 5.16  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.  Don't print usage twice.
+ *
+ * Revision 5.15  1993/11/03 17:42:27  eggert
+ * Add -z.  Ignore -T.  Pass -Vn to `co'.  Add Name keyword.
+ * Put revision numbers in -c output.  Improve quality of diagnostics.
+ *
+ * Revision 5.14  1992/07/28  16:12:44  eggert
+ * Add -V.  Use co -M for better dates with traditional diff -c.
+ *
+ * Revision 5.13  1992/02/17  23:02:23  eggert
+ * Output more readable context diff headers.
+ * Suppress needless checkout and comparison of identical revisions.
+ *
+ * Revision 5.12  1992/01/24  18:44:19  eggert
+ * Add GNU diff 1.15.2's new options.  lint -> RCS_lint
+ *
+ * Revision 5.11  1992/01/06  02:42:34  eggert
+ * Update usage string.
+ *
+ * Revision 5.10  1991/10/07  17:32:46  eggert
+ * Remove lint.
+ *
+ * Revision 5.9  1991/08/19  03:13:55  eggert
+ * Add RCSINIT, -r$.  Tune.
+ *
+ * Revision 5.8  1991/04/21  11:58:21  eggert
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.7  1990/12/13  06:54:07  eggert
+ * GNU diff 1.15 has -u.
+ *
+ * Revision 5.6  1990/11/01  05:03:39  eggert
+ * Remove unneeded setid check.
+ *
+ * Revision 5.5  1990/10/04  06:30:19  eggert
+ * Accumulate exit status across files.
+ *
+ * Revision 5.4  1990/09/27  01:31:43  eggert
+ * Yield 1, not EXIT_FAILURE, when diffs are found.
+ *
+ * Revision 5.3  1990/09/11  02:41:11  eggert
+ * Simplify -kkvl test.
+ *
+ * Revision 5.2  1990/09/04  17:07:19  eggert
+ * Diff's argv was too small by 1.
+ *
+ * Revision 5.1  1990/08/29  07:13:55  eggert
+ * Add -kkvl.
+ *
+ * Revision 5.0  1990/08/22  08:12:46  eggert
+ * Add -k, -V.  Don't use access().  Add setuid support.
+ * Remove compile-time limits; use malloc instead.
+ * Don't pass arguments with leading '+' to diff; GNU DIFF treats them as options.
+ * Add GNU diff's flags.  Make lock and temp files faster and safer.
+ * Ansify and Posixate.
+ *
+ * Revision 4.6  89/05/01  15:12:27  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.5  88/08/09  19:12:41  eggert
+ * Use execv(), not system(); yield exit status like diff(1)s; allow cc -R.
+ *
+ * Revision 4.4  87/12/18  11:37:46  narten
+ * changes Jay Lepreau made in the 4.3 BSD version, to add support for
+ * "-i", "-w", and "-t" flags and to permit flags to be bundled together,
+ * merged in.
+ *
+ * Revision 4.3  87/10/18  10:31:42  narten
+ * Updating version numbers. Changes relative to 1.1 actually
+ * relative to 4.1
+ *
+ * Revision 1.3  87/09/24  13:59:21  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:15  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/05/03  22:13:19  wft
+ * Added default branch, option -q, exit status like diff.
+ * Added fterror() to replace faterror().
+ *
+ * Revision 3.6  83/01/15  17:52:40  wft
+ * Expanded mainprogram to handle multiple RCS files.
+ *
+ * Revision 3.5  83/01/06  09:33:45  wft
+ * Fixed passing of -c (context) option to diff.
+ *
+ * Revision 3.4  82/12/24  15:28:38  wft
+ * Added call to catchsig().
+ *
+ * Revision 3.3  82/12/10  16:08:17  wft
+ * Corrected checking of return code from diff; improved error msgs.
+ *
+ * Revision 3.2  82/12/04  13:20:09  wft
+ * replaced getdelta() with gettree(). Changed diagnostics.
+ *
+ * Revision 3.1  82/11/28  19:25:04  wft
+ * Initial revision.
+ *
+ */
+#include "rcsbase.h"
+
+#if DIFF_L
+static char const *setup_label P((struct buf*,char const*,char const[datesize]));
+#endif
+static void cleanup P((void));
+
+static int exitstatus;
+static RILE *workptr;
+static struct stat workstat;
+
+mainProg(rcsdiffId, "rcsdiff", "$FreeBSD$")
+{
+    static char const cmdusage[] =
+	    "\nrcsdiff usage: rcsdiff -ksubst -q -rrev1 [-rrev2] -Vn -xsuff -zzone [diff options] file ...";
+
+    int  revnums;                 /* counter for revision numbers given */
+    char const *rev1, *rev2;	/* revision numbers from command line */
+    char const *xrev1, *xrev2;	/* expanded revision numbers */
+    char const *expandarg, *lexpandarg, *suffixarg, *versionarg, *zonearg;
+#if DIFF_L
+    static struct buf labelbuf[2];
+    int file_labels;
+    char const **diff_label1, **diff_label2;
+    char date2[datesize];
+#endif
+    char const *cov[10 + !DIFF_L];
+    char const **diffv, **diffp, **diffpend;	/* argv for subsidiary diff */
+    char const **pp, *p, *diffvstr;
+    struct buf commarg;
+    struct buf numericrev;	/* expanded revision number */
+    struct hshentries *gendeltas;	/* deltas to be generated */
+    struct hshentry * target;
+    char *a, *dcp, **newargv;
+    int no_diff_means_no_output;
+    register c;
+
+    exitstatus = DIFF_SUCCESS;
+
+    bufautobegin(&commarg);
+    bufautobegin(&numericrev);
+    revnums = 0;
+    rev1 = rev2 = xrev2 = 0;
+#if DIFF_L
+    file_labels = 0;
+#endif
+    expandarg = suffixarg = versionarg = zonearg = 0;
+    no_diff_means_no_output = true;
+    suffixes = X_DEFAULT;
+
+    /*
+    * Room for runv extra + args [+ --binary] [+ 2 labels]
+    * + 1 file + 1 trailing null.
+    */
+    diffv = tnalloc(char const*, 1 + argc + !!OPEN_O_BINARY + 2*DIFF_L + 2);
+    diffp = diffv + 1;
+    *diffp++ = DIFF;
+
+    argc = getRCSINIT(argc, argv, &newargv);
+    argv = newargv;
+    while (a = *++argv,  0<--argc && *a++=='-') {
+	dcp = a;
+	while ((c = *a++)) switch (c) {
+	    case 'r':
+		    switch (++revnums) {
+			case 1: rev1=a; break;
+			case 2: rev2=a; break;
+			default: error("too many revision numbers");
+		    }
+		    goto option_handled;
+	    case '-': case 'D':
+		    no_diff_means_no_output = false;
+		    /* fall into */
+	    case 'C': case 'F': case 'I': case 'L': case 'W':
+#if DIFF_L
+		    if (c == 'L'  &&  file_labels++ == 2)
+			faterror("too many -L options");
+#endif
+		    *dcp++ = c;
+		    if (*a)
+			do *dcp++ = *a++;
+			while (*a);
+		    else {
+			if (!--argc)
+			    faterror("-%c needs following argument%s",
+				    c, cmdusage
+			    );
+			*diffp++ = *argv++;
+		    }
+		    break;
+	    case 'y':
+		    no_diff_means_no_output = false;
+		    /* fall into */
+	    case 'B': case 'H':
+	    case '0': case '1': case '2': case '3': case '4':
+	    case '5': case '6': case '7': case '8': case '9':
+	    case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
+	    case 'h': case 'i': case 'n': case 'p':
+	    case 't': case 'u': case 'w':
+		    *dcp++ = c;
+		    break;
+	    case 'q':
+		    quietflag=true;
+		    break;
+	    case 'x':
+		    suffixarg = *argv;
+		    suffixes = *argv + 2;
+		    goto option_handled;
+	    case 'z':
+		    zonearg = *argv;
+		    zone_set(*argv + 2);
+		    goto option_handled;
+	    case 'T':
+		    /* Ignore -T, so that RCSINIT can contain -T.  */
+		    if (*a)
+			    goto unknown;
+		    break;
+	    case 'V':
+		    versionarg = *argv;
+		    setRCSversion(versionarg);
+		    goto option_handled;
+	    case 'k':
+		    expandarg = *argv;
+		    if (0 <= str2expmode(expandarg+2))
+			goto option_handled;
+		    /* fall into */
+	    default:
+	    unknown:
+		    error("unknown option: %s%s", *argv, cmdusage);
+	    };
+      option_handled:
+	if (dcp != *argv+1) {
+	    *dcp = 0;
+	    *diffp++ = *argv;
+	}
+    } /* end of option processing */
+
+    for (pp = diffv+2, c = 0;  pp<diffp;  )
+	    c += strlen(*pp++) + 1;
+    diffvstr = a = tnalloc(char, c + 1);
+    for (pp = diffv+2;  pp<diffp;  ) {
+	    p = *pp++;
+	    *a++ = ' ';
+	    while ((*a = *p++))
+		    a++;
+    }
+    *a = 0;
+
+#if DIFF_L
+    diff_label1 = diff_label2 = 0;
+    if (file_labels < 2) {
+	    if (!file_labels)
+		    diff_label1 = diffp++;
+	    diff_label2 = diffp++;
+    }
+#endif
+    diffpend = diffp;
+
+    cov[1] = CO;
+    cov[2] = "-q";
+#   if !DIFF_L
+	cov[3] = "-M";
+#   endif
+
+    /* Now handle all pathnames.  */
+    if (nerror)
+	cleanup();
+    else if (argc < 1)
+	faterror("no input file%s", cmdusage);
+    else
+	for (;  0 < argc;  cleanup(), ++argv, --argc) {
+	    ffree();
+
+	    if (pairnames(argc, argv, rcsreadopen, true, false)  <=  0)
+		    continue;
+	    diagnose("===================================================================\nRCS file: %s\n",RCSname);
+	    if (!rev2) {
+		/* Make sure work file is readable, and get its status.  */
+		if (!(workptr = Iopen(workname, FOPEN_R_WORK, &workstat))) {
+		    eerror(workname);
+		    continue;
+		}
+	    }
+
+
+	    gettree(); /* reads in the delta tree */
+
+	    if (!Head) {
+		    rcserror("no revisions present");
+		    continue;
+	    }
+	    if (revnums==0  ||  !*rev1)
+		    rev1  =  Dbranch ? Dbranch : Head->num;
+
+	    if (!fexpandsym(rev1, &numericrev, workptr)) continue;
+	    if (!(target=genrevs(numericrev.string,(char *)0,(char *)0,(char *)0,&gendeltas))) continue;
+	    xrev1=target->num;
+#if DIFF_L
+	    if (diff_label1)
+		*diff_label1 = setup_label(&labelbuf[0], target->num, target->date);
+#endif
+
+	    lexpandarg = expandarg;
+	    if (revnums==2) {
+		    if (!fexpandsym(
+			    *rev2 ? rev2  : Dbranch ? Dbranch  : Head->num,
+			    &numericrev,
+			    workptr
+		    ))
+			continue;
+		    if (!(target=genrevs(numericrev.string,(char *)0,(char *)0,(char *)0,&gendeltas))) continue;
+		    xrev2=target->num;
+		    if (no_diff_means_no_output  &&  xrev1 == xrev2)
+			continue;
+	    } else if (
+			target->lockedby
+		&&	!lexpandarg
+		&&	Expand == KEYVAL_EXPAND
+		&&	WORKMODE(RCSstat.st_mode,true) == workstat.st_mode
+	    )
+		    lexpandarg = "-kkvl";
+	    Izclose(&workptr);
+#if DIFF_L
+	    if (diff_label2)
+		if (revnums == 2)
+		    *diff_label2 = setup_label(&labelbuf[1], target->num, target->date);
+		else {
+		    time2date(workstat.st_mtime, date2);
+		    *diff_label2 = setup_label(&labelbuf[1], (char*)0, date2);
+		}
+#endif
+
+	    diagnose("retrieving revision %s\n", xrev1);
+	    bufscpy(&commarg, "-p");
+	    bufscat(&commarg, rev1); /* not xrev1, for $Name's sake */
+
+	    pp = &cov[3 + !DIFF_L];
+	    *pp++ = commarg.string;
+	    if (lexpandarg) *pp++ = lexpandarg;
+	    if (suffixarg) *pp++ = suffixarg;
+	    if (versionarg) *pp++ = versionarg;
+	    if (zonearg) *pp++ = zonearg;
+	    *pp++ = RCSname;
+	    *pp = 0;
+
+	    diffp = diffpend;
+#	    if OPEN_O_BINARY
+		    if (Expand == BINARY_EXPAND)
+			    *diffp++ = "--binary";
+#	    endif
+	    diffp[0] = maketemp(0);
+	    if (runv(-1, diffp[0], cov)) {
+		    rcserror("co failed");
+		    continue;
+	    }
+	    if (!rev2) {
+		    diffp[1] = workname;
+		    if (*workname == '-') {
+			char *dp = ftnalloc(char, strlen(workname)+3);
+			diffp[1] = dp;
+			*dp++ = '.';
+			*dp++ = SLASH;
+			VOID strcpy(dp, workname);
+		    }
+	    } else {
+		    diagnose("retrieving revision %s\n",xrev2);
+		    bufscpy(&commarg, "-p");
+		    bufscat(&commarg, rev2); /* not xrev2, for $Name's sake */
+		    cov[3 + !DIFF_L] = commarg.string;
+		    diffp[1] = maketemp(1);
+		    if (runv(-1, diffp[1], cov)) {
+			    rcserror("co failed");
+			    continue;
+		    }
+	    }
+	    if (!rev2)
+		    diagnose("diff%s -r%s %s\n", diffvstr, xrev1, workname);
+	    else
+		    diagnose("diff%s -r%s -r%s\n", diffvstr, xrev1, xrev2);
+
+	    diffp[2] = 0;
+	    switch (runv(-1, (char*)0, diffv)) {
+		    case DIFF_SUCCESS:
+			    break;
+		    case DIFF_FAILURE:
+			    if (exitstatus == DIFF_SUCCESS)
+				    exitstatus = DIFF_FAILURE;
+			    break;
+		    default:
+			    workerror("diff failed");
+	    }
+	}
+
+    tempunlink();
+    exitmain(exitstatus);
+}
+
+    static void
+cleanup()
+{
+    if (nerror) exitstatus = DIFF_TROUBLE;
+    Izclose(&finptr);
+    Izclose(&workptr);
+}
+
+#if RCS_lint
+#	define exiterr rdiffExit
+#endif
+    void
+exiterr()
+{
+    tempunlink();
+    _exit(DIFF_TROUBLE);
+}
+
+#if DIFF_L
+	static char const *
+setup_label(b, num, date)
+	struct buf *b;
+	char const *num;
+	char const date[datesize];
+{
+	char *p;
+	char datestr[datesize + zonelenmax];
+	VOID date2str(date, datestr);
+	bufalloc(b,
+		strlen(workname)
+		+ sizeof datestr + 4
+		+ (num ? strlen(num) : 0)
+	);
+	p = b->string;
+	if (num)
+		VOID sprintf(p, "-L%s\t%s\t%s", workname, datestr, num);
+	else
+		VOID sprintf(p, "-L%s\t%s", workname, datestr);
+	return p;
+}
+#endif
diff --git a/gnu/usr.bin/rcs/rcsfreeze/Makefile b/gnu/usr.bin/rcs/rcsfreeze/Makefile
new file mode 100644
index 0000000000000..1b249c737f177
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsfreeze/Makefile
@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+SCRIPTS= rcsfreeze.sh
+MAN=	rcsfreeze.1
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.1 b/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.1
new file mode 100644
index 0000000000000..3f513c4d65add
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.1
@@ -0,0 +1,68 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \s-1RCS\s0
+.TH RCSFREEZE 1 \*(Dt GNU
+.SH NAME
+rcsfreeze \- freeze a configuration of sources checked in under RCS
+.SH SYNOPSIS
+.B rcsfreeze
+.RI [ "name" ]
+.SH DESCRIPTION
+.B rcsfreeze
+assigns a symbolic revision
+number to a set of \*r files that form a valid configuration.
+.PP
+The idea is to run
+.B rcsfreeze
+each time a new version is checked
+in.  A unique symbolic name (\c
+.BI C_ number,
+where
+.I number
+is increased each time
+.B rcsfreeze
+is run) is then assigned to the most
+recent revision of each \*r file of the main trunk.
+.PP
+An optional
+.I name
+argument to
+.B rcsfreeze
+gives a symbolic name to the configuration.
+The unique identifier is still generated
+and is listed in the log file but it will not appear as
+part of the symbolic revision name in the actual \*r files.
+.PP
+A log message is requested from the user for future reference.
+.PP
+The shell script works only on all \*r files at one time.
+All changed files must be checked in already.
+Run
+.IR rcsclean (1)
+first and see whether any sources remain in the current directory.
+.SH FILES
+.TP
+.B RCS/.rcsfreeze.ver
+version number
+.TP
+.B RCS/.rcsfreeze.log
+log messages, most recent first
+.SH AUTHOR
+Stephan v. Bechtolsheim
+.SH "SEE ALSO"
+co(1), rcs(1), rcsclean(1), rlog(1)
+.SH BUGS
+.B rcsfreeze
+does not check whether any sources are checked out and modified.
+.PP
+Although both source file names and RCS file names are accepted,
+they are not paired as usual with RCS commands.
+.PP
+Error checking is rudimentary.
+.PP
+.B rcsfreeze
+is just an optional example shell script, and should not be taken too seriously.
+See \s-1CVS\s0 for a more complete solution.
diff --git a/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.sh b/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.sh
new file mode 100644
index 0000000000000..be79406fe0c14
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsfreeze/rcsfreeze.sh
@@ -0,0 +1,99 @@
+#! /bin/sh
+
+# rcsfreeze - assign a symbolic revision number to a configuration of RCS files
+
+# $FreeBSD$
+
+#       The idea is to run rcsfreeze each time a new version is checked
+#       in. A unique symbolic revision number (C_[number], where number
+#       is increased each time rcsfreeze is run) is then assigned to the most
+#       recent revision of each RCS file of the main trunk.
+#
+#       If the command is invoked with an argument, then this
+#       argument is used as the symbolic name to freeze a configuration.
+#       The unique identifier is still generated
+#       and is listed in the log file but it will not appear as
+#       part of the symbolic revision name in the actual RCS file.
+#
+#       A log message is requested from the user which is saved for future
+#       references.
+#
+#       The shell script works only on all RCS files at one time.
+#       It is important that all changed files are checked in (there are
+#       no precautions against any error in this respect).
+#       file names:
+#       {RCS/}.rcsfreeze.ver	version number
+#       {RCS/}.rscfreeze.log	log messages, most recent first
+
+PATH=/bin:/usr/bin:$PATH
+export PATH
+
+DATE=`LC_ALL=C date` || exit
+# Check whether we have an RCS subdirectory, so we can have the right
+# prefix for our paths.
+if test -d RCS
+then RCSDIR=RCS/ EXT=
+else RCSDIR= EXT=,v
+fi
+
+# Version number stuff, log message file
+VERSIONFILE=${RCSDIR}.rcsfreeze.ver
+LOGFILE=${RCSDIR}.rcsfreeze.log
+# Initialize, rcsfreeze never run before in the current directory
+test -r $VERSIONFILE || { echo 0 >$VERSIONFILE && >>$LOGFILE; } || exit
+
+# Get Version number, increase it, write back to file.
+VERSIONNUMBER=`cat $VERSIONFILE` &&
+VERSIONNUMBER=`expr $VERSIONNUMBER + 1` &&
+echo $VERSIONNUMBER >$VERSIONFILE || exit
+
+# Symbolic Revision Number
+SYMREV=C_$VERSIONNUMBER
+# Allow the user to give a meaningful symbolic name to the revision.
+SYMREVNAME=${1-$SYMREV}
+echo >&2 "rcsfreeze: symbolic revision number computed: \"${SYMREV}\"
+rcsfreeze: symbolic revision number used:     \"${SYMREVNAME}\"
+rcsfreeze: the two differ only when rcsfreeze invoked with argument
+rcsfreeze: give log message, summarizing changes (end with EOF or single '.')" \
+	|| exit
+
+# Stamp the logfile. Because we order the logfile the most recent
+# first we will have to save everything right now in a temporary file.
+TMPLOG=/tmp/rcsfrz$$
+trap 'rm -f $TMPLOG; exit 1' 1 2 13 15
+# Now ask for a log message, continously add to the log file
+(
+	echo "Version: $SYMREVNAME($SYMREV), Date: $DATE
+-----------" || exit
+	while read MESS
+	do
+		case $MESS in
+		.) break
+		esac
+		echo "	$MESS" || exit
+	done
+	echo "-----------
+" &&
+	cat $LOGFILE
+) >$TMPLOG &&
+
+# combine old and new logfiles
+cp $TMPLOG $LOGFILE &&
+rm -f $TMPLOG &&
+
+# Now the real work begins by assigning a symbolic revision number
+# to each rcs file.  Take the most recent version on the default branch.
+
+# If there are any .*,v files, throw them in too.
+# But ignore RCS/.* files that do not end in ,v.
+DOTFILES=
+for DOTFILE in ${RCSDIR}.*,v
+do
+	if test -f "$DOTFILE"
+	then
+		DOTFILES="${RCSDIR}.*,v"
+		break
+	fi
+done
+
+exec rcs -q -n$SYMREVNAME: ${RCSDIR}*$EXT $DOTFILES
diff --git a/gnu/usr.bin/rcs/rcsmerge/Makefile b/gnu/usr.bin/rcs/rcsmerge/Makefile
new file mode 100644
index 0000000000000..9fd8afaab0205
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsmerge/Makefile
@@ -0,0 +1,8 @@
+PROG=	rcsmerge
+SRCS=	rcsmerge.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=	${LIBRCS}
+DPADD=	${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rcsmerge/rcsmerge.1 b/gnu/usr.bin/rcs/rcsmerge/rcsmerge.1
new file mode 100644
index 0000000000000..aff6f666dabb6
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsmerge/rcsmerge.1
@@ -0,0 +1,189 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds r \&\s-1RCS\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH RCSMERGE 1 \*(Dt GNU
+.SH NAME
+rcsmerge \- merge RCS revisions
+.SH SYNOPSIS
+.B rcsmerge
+.RI [ options ] " file"
+.SH DESCRIPTION
+.B rcsmerge
+incorporates the changes between two revisions
+of an \*r file into the corresponding working file.
+.PP
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+Names are paired as explained in
+.BR ci (1).
+.PP
+At least one revision must be specified with one of the options
+described below, usually
+.BR \-r .
+At most two revisions may be specified.
+If only one revision is specified, the latest
+revision on the default branch (normally the highest branch on the trunk)
+is assumed for the second revision.
+Revisions may be specified numerically or symbolically.
+.PP
+.B rcsmerge
+prints a warning if there are overlaps, and delimits
+the overlapping regions as explained in
+.BR merge (1).
+The command is useful for incorporating changes into a checked-out revision.
+.SH OPTIONS
+.TP
+.B \-A
+Output conflicts using the
+.B \-A
+style of
+.BR diff3 (1),
+if supported by
+.BR diff3 .
+This merges all changes leading from
+.I file2
+to
+.I file3
+into
+.IR file1 ,
+and generates the most verbose output.
+.TP
+\f3\-E\fP, \f3\-e\fP
+These options specify conflict styles that generate less information
+than
+.BR \-A .
+See
+.BR diff3 (1)
+for details.
+The default is
+.BR \-E .
+With
+.BR \-e ,
+.B rcsmerge
+does not warn about conflicts.
+.TP
+.BI \-k subst
+Use
+.I subst
+style keyword substitution.
+See
+.BR co (1)
+for details.
+For example,
+.B "\-kk\ \-r1.1\ \-r1.2"
+ignores differences in keyword values when merging the changes from
+.B 1.1
+to
+.BR 1.2 .
+It normally does not make sense to merge binary files as if they were text, so
+.B rcsmerge
+refuses to merge files if
+.B \-kb
+expansion is used.
+.TP
+.BR \-p [\f2rev\fP]
+Send the result to standard output instead of overwriting the working file.
+.TP
+.BR \-q [\f2rev\fP]
+Run quietly; do not print diagnostics.
+.TP
+.BR \-r [\f2rev\fP]
+Merge with respect to revision
+.IR rev .
+Here an empty
+.I rev
+stands for the latest revision on the default branch, normally the head.
+.TP
+.B \-T
+This option has no effect;
+it is present for compatibility with other \*r commands.
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.IR n .
+See
+.BR co (1)
+for details.
+.TP
+.BI \-x "suffixes"
+Use
+.I suffixes
+to characterize \*r files.
+See
+.BR ci (1)
+for details.
+.TP
+.BI \-z zone
+Use
+.I zone
+as the time zone for keyword substitution.
+See
+.BR co (1)
+for details.
+.SH EXAMPLES
+Suppose you have released revision 2.8 of
+.BR f.c .
+Assume
+furthermore that after you complete an unreleased revision 3.4, you receive
+updates to release 2.8 from someone else.
+To combine the updates to 2.8 and your changes between 2.8 and 3.4,
+put the updates to 2.8 into file f.c and execute
+.LP
+.B "    rcsmerge  \-p  \-r2.8  \-r3.4  f.c  >f.merged.c"
+.PP
+Then examine
+.BR f.merged.c .
+Alternatively, if you want to save the updates to 2.8 in the \*r file,
+check them in as revision 2.8.1.1 and execute
+.BR "co \-j":
+.LP
+.B "    ci  \-r2.8.1.1  f.c"
+.br
+.B "    co  \-r3.4  \-j2.8:2.8.1.1  f.c"
+.PP
+As another example, the following command undoes the changes
+between revision 2.4 and 2.8 in your currently checked out revision
+in
+.BR f.c .
+.LP
+.B "    rcsmerge  \-r2.8  \-r2.4  f.c"
+.PP
+Note the order of the arguments, and that
+.B f.c
+will be
+overwritten.
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+See
+.BR ci (1)
+for details.
+.SH DIAGNOSTICS
+Exit status is 0 for no overlaps, 1 for some overlaps, 2 for trouble.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), ident(1), merge(1), rcs(1), rcsdiff(1), rcsintro(1), rlog(1),
+rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.br
diff --git a/gnu/usr.bin/rcs/rcsmerge/rcsmerge.c b/gnu/usr.bin/rcs/rcsmerge/rcsmerge.c
new file mode 100644
index 0000000000000..e09dc2469867f
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcsmerge/rcsmerge.c
@@ -0,0 +1,286 @@
+/* Merge RCS revisions.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.15  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.14  1995/06/01 16:23:43  eggert
+ * (main): Report an error if -kb, so don't worry about binary stdout.
+ * Punctuate messages properly.  Rewrite to avoid `goto end'.
+ *
+ * Revision 5.13  1994/03/17 14:05:48  eggert
+ * Specify subprocess input via file descriptor, not file name.  Remove lint.
+ *
+ * Revision 5.12  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.  Don't print usage twice.
+ *
+ * Revision 5.11  1993/11/03 17:42:27  eggert
+ * Add -A, -E, -e, -z.  Ignore -T.  Allow up to three file labels.
+ * Pass -Vn to `co'.  Pass unexpanded revision name to `co', so that Name works.
+ *
+ * Revision 5.10  1992/07/28  16:12:44  eggert
+ * Add -V.
+ *
+ * Revision 5.9  1992/01/24  18:44:19  eggert
+ * lint -> RCS_lint
+ *
+ * Revision 5.8  1992/01/06  02:42:34  eggert
+ * Update usage string.
+ *
+ * Revision 5.7  1991/11/20  17:58:09  eggert
+ * Don't Iopen(f, "r+"); it's not portable.
+ *
+ * Revision 5.6  1991/08/19  03:13:55  eggert
+ * Add -r$.  Tune.
+ *
+ * Revision 5.5  1991/04/21  11:58:27  eggert
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.4  1991/02/25  07:12:43  eggert
+ * Merging a revision to itself is no longer an error.
+ *
+ * Revision 5.3  1990/11/01  05:03:50  eggert
+ * Remove unneeded setid check.
+ *
+ * Revision 5.2  1990/09/04  08:02:28  eggert
+ * Check for I/O error when reading working file.
+ *
+ * Revision 5.1  1990/08/29  07:14:04  eggert
+ * Add -q.  Pass -L options to merge.
+ *
+ * Revision 5.0  1990/08/22  08:13:41  eggert
+ * Propagate merge's exit status.
+ * Remove compile-time limits; use malloc instead.
+ * Make lock and temp files faster and safer.  Ansify and Posixate.  Add -V.
+ * Don't use access().  Tune.
+ *
+ * Revision 4.5  89/05/01  15:13:16  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.4  88/08/09  19:13:13  eggert
+ * Beware merging into a readonly file.
+ * Beware merging a revision to itself (no change).
+ * Use execv(), not system(); yield exit status like diff(1)'s.
+ *
+ * Revision 4.3  87/10/18  10:38:02  narten
+ * Updating version numbers. Changes relative to version 1.1
+ * actually relative to 4.1
+ *
+ * Revision 1.3  87/09/24  14:00:31  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:36  jenkins
+ * Port to suns
+ *
+ * Revision 4.1  83/03/28  11:14:57  wft
+ * Added handling of default branch.
+ *
+ * Revision 3.3  82/12/24  15:29:00  wft
+ * Added call to catchsig().
+ *
+ * Revision 3.2  82/12/10  21:32:02  wft
+ * Replaced getdelta() with gettree(); improved error messages.
+ *
+ * Revision 3.1  82/11/28  19:27:44  wft
+ * Initial revision.
+ *
+ */
+#include "rcsbase.h"
+
+static char const co[] = CO;
+
+mainProg(rcsmergeId, "rcsmerge", "$FreeBSD$")
+{
+	static char const cmdusage[] =
+		"\nrcsmerge usage: rcsmerge -rrev1 [-rrev2] -ksubst -{pq}[rev] -Vn -xsuff -zzone file";
+	static char const quietarg[] = "-q";
+
+	register int i;
+	char *a, **newargv;
+	char const *arg[3];
+	char const *rev[3], *xrev[3]; /*revision numbers*/
+	char const *edarg, *expandarg, *suffixarg, *versionarg, *zonearg;
+        int tostdout;
+	int status;
+	RILE *workptr;
+	struct buf commarg;
+	struct buf numericrev; /* holds expanded revision number */
+	struct hshentries *gendeltas; /* deltas to be generated */
+        struct hshentry * target;
+
+	bufautobegin(&commarg);
+	bufautobegin(&numericrev);
+	edarg = rev[1] = rev[2] = 0;
+	status = 0; /* Keep lint happy.  */
+	tostdout = false;
+	expandarg = suffixarg = versionarg = zonearg = quietarg; /* no-op */
+	suffixes = X_DEFAULT;
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	while (a = *++argv,  0<--argc && *a++=='-') {
+		switch (*a++) {
+                case 'p':
+                        tostdout=true;
+			goto revno;
+
+		case 'q':
+			quietflag = true;
+		revno:
+			if (!*a)
+				break;
+                        /* falls into -r */
+                case 'r':
+			if (!rev[1])
+				rev[1] = a;
+			else if (!rev[2])
+				rev[2] = a;
+			else
+				error("too many revision numbers");
+                        break;
+
+		case 'A': case 'E': case 'e':
+			if (*a)
+				goto unknown;
+			edarg = *argv;
+			break;
+
+		case 'x':
+			suffixarg = *argv;
+			suffixes = a;
+			break;
+		case 'z':
+			zonearg = *argv;
+			zone_set(a);
+			break;
+		case 'T':
+			/* Ignore -T, so that RCSINIT can contain -T.  */
+			if (*a)
+				goto unknown;
+			break;
+		case 'V':
+			versionarg = *argv;
+			setRCSversion(versionarg);
+			break;
+
+		case 'k':
+			expandarg = *argv;
+			if (0 <= str2expmode(expandarg+2))
+			    break;
+			/* fall into */
+                default:
+		unknown:
+			error("unknown option: %s%s", *argv, cmdusage);
+                };
+        } /* end of option processing */
+
+	if (!rev[1]) faterror("no base revision number given");
+
+	/* Now handle all pathnames.  */
+
+	if (!nerror) {
+	    if (argc < 1)
+		faterror("no input file%s", cmdusage);
+	    if (0 < pairnames(argc, argv, rcsreadopen, true, false)) {
+
+                if (argc>2  ||  (argc==2 && argv[1]))
+			warn("excess arguments ignored");
+		if (Expand == BINARY_EXPAND)
+			workerror("merging binary files");
+		diagnose("RCS file: %s\n", RCSname);
+		if (!(workptr = Iopen(workname, FOPEN_R_WORK, (struct stat*)0)))
+			efaterror(workname);
+
+                gettree();  /* reads in the delta tree */
+
+		if (!Head) rcsfaterror("no revisions present");
+
+		if (!*rev[1])
+			rev[1]  =  Dbranch ? Dbranch : Head->num;
+		if (fexpandsym(rev[1], &numericrev, workptr)
+		    && (target=genrevs(numericrev.string, (char *)0, (char *)0, (char*)0, &gendeltas))
+		) {
+		  xrev[1] = target->num;
+		  if (!rev[2] || !*rev[2])
+			rev[2]  =  Dbranch ? Dbranch : Head->num;
+		  if (fexpandsym(rev[2], &numericrev, workptr)
+		      && (target=genrevs(numericrev.string, (char *)0, (char *)0, (char *)0, &gendeltas))
+		  ) {
+		    xrev[2] = target->num;
+
+		    if (strcmp(xrev[1],xrev[2]) == 0) {
+		      if (tostdout) {
+			fastcopy(workptr, stdout);
+			Ofclose(stdout);
+		      }
+		    } else {
+		      Izclose(&workptr);
+
+		      for (i=1; i<=2; i++) {
+			diagnose("retrieving revision %s\n", xrev[i]);
+			bufscpy(&commarg, "-p");
+			bufscat(&commarg, rev[i]); /* not xrev[i], for $Name's sake */
+			if (run(
+				-1,
+				/* Do not collide with merger.c maketemp().  */
+				arg[i] = maketemp(i+2),
+				co, quietarg, commarg.string,
+				expandarg, suffixarg, versionarg, zonearg,
+				RCSname, (char*)0
+			))
+				rcsfaterror("co failed");
+		      }
+		      diagnose("Merging differences between %s and %s into %s%s\n",
+			       xrev[1], xrev[2], workname,
+			       tostdout?"; result to stdout":"");
+
+		      arg[0] = xrev[0] = workname;
+		      status = merge(tostdout, edarg, xrev, arg);
+		    }
+		  }
+		}
+
+		Izclose(&workptr);
+	    }
+        }
+	tempunlink();
+	exitmain(nerror ? DIFF_TROUBLE : status);
+}
+
+#if RCS_lint
+#	define exiterr rmergeExit
+#endif
+	void
+exiterr()
+{
+	tempunlink();
+	_exit(DIFF_TROUBLE);
+}
diff --git a/gnu/usr.bin/rcs/rcstest b/gnu/usr.bin/rcs/rcstest
new file mode 100755
index 0000000000000..75165f1bbd59e
--- /dev/null
+++ b/gnu/usr.bin/rcs/rcstest
@@ -0,0 +1,454 @@
+#! /bin/sh
+
+# Test RCS's functions.
+# The RCS commands are searched for in the PATH as usual;
+# to test the working directory's commands, prepend . to your PATH.
+
+# Test RCS by creating files RCS/a.* and RCS/a.c.
+# If all goes well, output nothing, and remove the temporary files.
+# Otherwise, send a message to standard output.
+# Exit status is 0 if OK, 1 if an RCS bug is found, and 2 if scaffolding fails.
+# With the -v option, output more debugging info.
+
+# If diff outputs `No differences encountered' when comparing identical files,
+# then rcstest may also output these noise lines; ignore them.
+
+# The current directory and ./RCS must be readable, writable, and searchable.
+
+# $FreeBSD$
+
+
+#    Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+#    Distributed under license by the Free Software Foundation, Inc.
+#
+# This file is part of RCS.
+#
+# RCS is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+#
+# RCS is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with RCS; see the file COPYING.
+# If not, write to the Free Software Foundation,
+# 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+#
+# Report problems and direct all questions to:
+#
+#     rcs-bugs@cs.purdue.edu
+
+# The Makefile overrides the following defaults.
+: ${ALL_CFLAGS=-Dhas_conf_h}
+: ${CC=cc}
+: ${DIFF=diff}
+# : ${LDFLAGS=} ${LIBS=} tickles old shell bug
+
+CL="$CC $ALL_CFLAGS $LDFLAGS -o a.out"
+L=$LIBS
+
+RCSINIT=-x
+export RCSINIT
+
+SLASH=/
+RCSfile=RCS${SLASH}a.c
+RCS_alt=RCS${SLASH}a.d
+lockfile=RCS${SLASH}a._
+
+case $1 in
+-v) q=; set -x;;
+'') q=-q;;
+*) echo >&2 "$0: usage: $0 [-v]"; exit 2
+esac
+
+if test -d RCS
+then rmdir=:
+else rmdir=rmdir; mkdir RCS || exit
+fi
+
+rm -f a.* $RCSfile $RCS_alt $lockfile &&
+echo 1.1 >a.11 &&
+echo 1.1.1.1 >a.3x1 &&
+echo 1.2 >a.12 || { echo "#initialization failed"; exit 2; }
+
+case "`$DIFF -c a.11 a.3x1`" in
+*!\ 1.1.1.1)
+	diff="$DIFF -c";;
+*)
+	echo "#warning: $DIFF -c does not work, so diagnostics may be cryptic"
+	diff=$DIFF
+esac
+
+rcs -i -L -ta.11 $q a.c &&
+test -r $RCSfile || {
+	echo "#rcs -i -L failed; perhaps RCS is not properly installed."
+	exit 1
+}
+
+rlog a.c >/dev/null || { echo "#rlog failed on empty RCS file"; exit 1; }
+rm -f $RCSfile || exit 2
+
+cp a.11 a.c &&
+ci -ta.11 -mm $q a.c &&
+test -r $RCSfile &&
+rcs -L $q a.c || { echo "#ci+rcs -L failed"; exit 1; }
+test ! -f a.c || { echo "#ci did not remove working file"; exit 1; }
+for l in '' '-l'
+do
+	co $l $q a.c &&
+	test -f a.c || { echo '#co' $l did not create working file; exit 1; }
+	$diff a.11 a.c || { echo '#ci' followed by co $l is not a no-op; exit 1; }
+done
+
+cp a.12 a.c &&
+ci -mm $q a.c &&
+co $q a.c &&
+$diff a.12 a.c || { echo "#ci+co failed"; exit 1; }
+
+rm -f a.c &&
+co -r1.1 $q a.c &&
+$diff a.11 a.c || { echo "#can't retrieve first revision"; exit 1; }
+
+rm -f a.c &&
+cp a.3x1 a.c &&
+ci -r1.1.1 -mm $q a.c &&
+co -r1.1.1.1 $q a.c &&
+$diff a.3x1 a.c || { echo "#branches failed"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+ci -f -mm $q a.c &&
+co -r1.3 $q a.c &&
+$diff a.12 a.c || { echo "#(co -l; ci -f) failed"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+echo 1.4 >a.c &&
+ci -l -mm $q a.c &&
+echo error >a.c &&
+ci -mm $q a.c || { echo "#ci -l failed"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+echo 1.5 >a.c &&
+ci -u -mm $q a.c &&
+test -r a.c || { echo "#ci -u didn't create a working file"; exit 1; }
+rm -f a.c &&
+echo error >a.c || exit 2
+ci -mm $q a.c 2>/dev/null && { echo "#ci -u didn't unlock the file"; exit 1; }
+
+rm -f a.c &&
+rcs -l $q a.c &&
+co -u $q a.c || { echo "#rcs -l + co -u failed"; exit 1; }
+rm -f a.c &&
+echo error >a.c || exit 2
+ci -mm $q a.c 2>/dev/null && { echo "#co -u didn't unlock the file"; exit 1; }
+
+rm -f a.c &&
+cp a.11 a.c &&
+co -f $q a.c || { echo "#co -f failed"; exit 1; }
+$diff a.11 a.c >/dev/null && { echo "#co -f had no effect"; exit 1; }
+
+co -p1.1 $q a.c >a.t &&
+$diff a.11 a.t || { echo "#co -p failed"; exit 1; }
+
+for n in n N
+do
+	rm -f a.c &&
+	co -l $q a.c &&
+	echo $n >a.$n &&
+	cp a.$n a.c &&
+	ci -${n}n -mm $q a.c &&
+	co -rn $q a.c &&
+	$diff a.$n a.c || { echo "#ci -$n failed"; exit 1; }
+done
+
+case $LOGNAME in
+?*) me=$LOGNAME;;
+*)
+	case $USER in
+	?*) me=$USER;;
+	*)
+		me=`who am i` || exit 2
+		me=`echo "$me" | sed -e 's/ .*//' -e 's/.*!//'`
+		case $me in
+		'') echo >&2 "$0: cannot deduce user name"; exit 2
+		esac
+	esac
+esac
+
+
+# Get the date of the previous revision in UTC.
+date=`rlog -r a.c | sed -n '/^date: /{ s///; s/;.*//; p; q; }'` || exit
+case $date in
+[0-9][0-9][0-9]*[0-9]/[0-1][0-9]/[0-3][0-9]\ [0-2][0-9]:[0-5][0-9]:[0-6][0-9]);;
+*) echo >&2 "$0: $date: bad rlog date output"; exit 1
+esac
+PWD=`pwd` && export PWD &&
+rm -f a.c &&
+co -l $q a.c &&
+sed 's/@/$/g' >a.kv <<EOF
+@Author: w @
+@Date: $date @
+@Header: $PWD$SLASH$RCSfile 2.1 $date w s @
+@Id: a.c 2.1 $date w s @
+@Locker:  @
+ * @Log: a.c @
+ * Revision 2.1  $date  w
+ * m
+ *
+@Name: Oz @
+@RCSfile: a.c @
+@Revision: 2.1 @
+@Source: $PWD$SLASH$RCSfile @
+@State: s @
+EOF
+test $? = 0 &&
+sed 's/:.*\$/$/' a.kv >a.k &&
+sed -e 's/w s [$]/w s '"$me"' $/' -e 's/[$]Locker: /&'"$me/" a.kv >a.kvl &&
+sed s/Oz//g a.kv >a.e &&
+sed s/Oz/N/g a.kv >a.N &&
+sed -e '/\$/!d' -e 's/\$$/: old $/' a.k >a.o &&
+sed -e 's/\$[^ ]*: //' -e 's/ \$//' a.kv >a.v &&
+cp a.o a.c &&
+ci -d"$date" -nOz -ss -ww -u2.1 -mm $q a.c &&
+$diff a.kv a.c || { echo "#keyword expansion failed"; exit 1; }
+co -pOz -ko $q a.c >a.oo &&
+$diff a.o a.oo || { echo "#co -p -ko failed"; exit 1; }
+cp a.kv a.o && cp a.o a.b || exit 2
+rcs -oOz $q a.c &&
+rcs -l $q a.c &&
+ci -k -u $q a.c &&
+$diff a.kv a.c || { echo "#ci -k failed"; exit 1; }
+sed -n 's/^[^$]*\$/$/p' a.kv >a.i &&
+ident a.c >a.i1 &&
+sed -e 1d -e 's/^[	 ]*//' a.i1 >a.i2 &&
+$diff a.i a.i2 || { echo "#ident failed"; exit 1; }
+
+rcs -i $q a.c 2>/dev/null && { echo "#rcs -i permitted existing file"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+echo 2.2 >a.c &&
+ci -mm $q a.c &&
+echo 1.1.1.2 >a.c &&
+rcs -l1.1.1 $q a.c &&
+ci -r1.1.1.2 -mm $q a.c &&
+rcs -b1.1.1 $q a.c &&
+test " `co -p $q a.c`" = ' 1.1.1.2' || { echo "#rcs -b1.1.1 failed"; exit 1; }
+rcs -b $q a.c &&
+test " `co -p $q a.c`" = ' 2.2' || { echo "#rcs -b failed"; exit 1; }
+
+echo 2.3 >a.c || exit 2
+rcs -U $q a.c || { echo "#rcs -U failed"; exit 1; }
+ci -mm $q a.c || { echo "#rcs -U didn't unset strict locking"; exit 1; }
+rcs -L $q a.c || { echo "#rcs -L failed"; exit 1; }
+echo error >a.c || exit 2
+ci -mm $q a.c 2>/dev/null && { echo "#ci retest failed"; exit 1; }
+
+rm -f a.c &&
+log0=`rlog -h a.c` &&
+co -l $q a.c &&
+ci -mm $q a.c &&
+log1=`rlog -h a.c` &&
+test " $log0" = " $log1" || { echo "#unchanged ci didn't revert"; exit 1; }
+
+rm -f a.c &&
+rcs -nN:1.1 $q a.c &&
+co -rN $q a.c &&
+$diff a.11 a.c || { echo "#rcs -n failed"; exit 1; }
+
+rm -f a.c &&
+rcs -NN:2.1 $q a.c &&
+co -rN $q a.c &&
+$diff a.N a.c || { echo "#rcs -N failed"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+echo ':::$''Log$' >a.c &&
+ci -u -mm $q a.c &&
+test " `sed '$!d' a.c`" = ' :::' || { echo "#comment leader failed"; exit 1; }
+
+rm -f a.c &&
+rcs -o2.2: $q a.c &&
+co $q a.c &&
+$diff a.e a.c || { echo "#rcs -o failed"; exit 1; }
+
+rcsdiff -r1.1 -rOz $q a.c >a.0
+case $? in
+1) ;;
+*) echo "#rcsdiff bad status"; exit 1
+esac
+$DIFF a.11 a.kv >a.1
+$diff a.0 a.1 || { echo "#rcsdiff failed"; exit 1; }
+
+rcs -l2.1 $q a.c || { echo "#rcs -l2.1 failed"; exit 1; }
+for i in b k kv kvl o v
+do
+	rm -f a.c &&
+	cp a.$i a.c &&
+	rcsdiff -k$i -rOz $q a.c || { echo "#rcsdiff -k$i failed"; exit 1; }
+done
+co -p1.1 -ko $q a.c >a.t &&
+$diff a.11 a.t || { echo "#co -p1.1 -ko failed"; exit 1; }
+rcs -u2.1 $q a.c || { echo "#rcs -u2.1 failed"; exit 1; }
+
+rm -f a.c &&
+rcsclean $q a.c &&
+rcsclean -u $q a.c || { echo "#rcsclean botched a nonexistent file"; exit 1; }
+
+rm -f a.c &&
+co $q a.c &&
+rcsclean -n $q a.c &&
+rcsclean -n -u $q a.c &&
+test -f a.c || { echo "#rcsclean -n removed a file"; exit 1; }
+
+rm -f a.c &&
+co $q a.c &&
+rcsclean $q a.c &&
+test ! -f a.c || { echo "#rcsclean missed an unlocked file"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+rcsclean $q a.c &&
+test -f a.c || { echo "#rcsclean removed a locked file"; exit 1; }
+rcsclean -u $q a.c &&
+test ! -f a.c || {
+	echo "#rcsclean -u missed an unchanged locked file"; exit 1;
+}
+
+rm -f a.c &&
+co -l $q a.c &&
+echo change >>a.c &&
+rcsclean $q a.c &&
+rcsclean $q -u a.c &&
+test -f a.c || { echo "#rcsclean removed a changed file"; exit 1; }
+
+rm -f a.c &&
+co -l $q a.c &&
+cat >a.c <<'EOF'
+2.2
+a
+b
+c
+d
+EOF
+test $? = 0 &&
+ci -l -mm $q a.c &&
+co -p2.2 $q a.c | sed -e s/2.2/2.3/ -e s/b/b1/ >a.c &&
+ci -l -mm $q a.c &&
+co -p2.2 $q a.c | sed -e s/2.2/new/ -e s/d/d1/ >a.c || exit 2
+cat >a.0 <<'EOF'
+2.3
+a
+b1
+c
+d1
+EOF
+cat >a.1 <<'EOF'
+<<<<<<< a.c
+new
+=======
+2.3
+>>>>>>> 2.3
+a
+b1
+c
+d1
+EOF
+rcsmerge -E -r2.2 -r2.3 $q a.c
+case $? in
+0)
+	if $diff a.0 a.c >/dev/null
+	then echo "#warning: diff3 -E does not work, " \
+		"so merge and rcsmerge ignore overlaps and suppress overlap lines."
+	else
+		$diff a.1 a.c || { echo "#rcsmerge failed (status 0)"; exit 1; }
+		echo "#warning: The diff3 lib program exit status ignores overlaps," \
+			"so rcsmerge does not warn about overlap lines that it generates."
+	fi
+	;;
+1)
+	$diff a.1 a.c || { echo "#rcsmerge failed (status 1)"; exit 1; }
+	;;
+*)
+	echo "#rcsmerge bad status"; exit 1
+esac
+
+# Avoid `tr' if possible; it's not portable, and it can't handle null bytes.
+# Our substitute exclusive-ORs with '\n';
+# this ensures null bytes on output, which is even better than `tr',
+# since some diffs think a file is binary only if it contains null bytes.
+cat >a.c <<'EOF'
+#include <stdio.h>
+int main() {
+	int c;
+	while ((c=getchar()) != EOF)
+		putchar(c ^ '\n');
+	return 0;
+}
+EOF
+tr=tr
+if (rm -f a.exe a.out && $CL a.c $L >&2) >/dev/null 2>&1
+then
+	if test -s a.out
+	then tr=./a.out
+	elif test -s a.exe
+	then tr=./a.exe
+	fi
+fi
+{
+	co -p $q a.c | $tr '\012' '\200' >a.24 &&
+	cp a.24 a.c &&
+	ciOut=`(ci -l -mm $q a.c 2>&1)` &&
+	case $ciOut in
+	?*) echo >&2 "$ciOut"
+	esac &&
+	co -p $q a.c | $tr '\200' '\012' >a.c &&
+	rcsdiff -r2.3 $q a.c >/dev/null &&
+
+	echo 2.5 >a.c &&
+	ci -l -mm $q a.c &&
+	cp a.24 a.c &&
+	rcsdiff -r2.4 $q a.c >/dev/null
+} || echo "#warning: Traditional diff is used, so RCS is limited to text files."
+
+rcs -u -o2.4: $q a.c || { echo "#rcs -u -o failed"; exit 1; }
+
+rcs -i -Aa.c -t- $q a.d || { echo "#rcs -i -A failed"; exit 1; }
+
+rlog -r2.1 a.c >a.t &&
+grep '^checked in with -k' a.t >/dev/null &&
+sed '/^checked in with -k/d' a.t >a.u &&
+$diff - a.u <<EOF
+
+RCS file: $RCSfile
+Working file: a.c
+head: 2.3
+branch:
+locks: strict
+access list:
+symbolic names:
+	N: 2.1
+	Oz: 2.1
+	n: 1.8
+keyword substitution: kv
+total revisions: 13;	selected revisions: 1
+description:
+1.1
+----------------------------
+revision 2.1
+date: $date;  author: w;  state: s;  lines: +14 -1
+=============================================================================
+EOF
+test $? = 0 || { echo "#rlog failed"; exit 1; }
+
+
+test ! -f $lockfile || { echo "#lock file not removed"; exit 1; }
+
+rm -f a.* $RCSfile $RCS_alt
+$rmdir RCS
diff --git a/gnu/usr.bin/rcs/rlog/Makefile b/gnu/usr.bin/rcs/rlog/Makefile
new file mode 100644
index 0000000000000..bdbf68f42711d
--- /dev/null
+++ b/gnu/usr.bin/rcs/rlog/Makefile
@@ -0,0 +1,8 @@
+PROG=	rlog
+SRCS=	rlog.c
+CFLAGS+= -I${.CURDIR}/../lib
+LDADD=  ${LIBRCS}
+DPADD=  ${LIBRCS}
+
+.include "../../Makefile.inc"
+.include <bsd.prog.mk>
diff --git a/gnu/usr.bin/rcs/rlog/rlog.1 b/gnu/usr.bin/rcs/rlog/rlog.1
new file mode 100644
index 0000000000000..26bf08a2bcb09
--- /dev/null
+++ b/gnu/usr.bin/rcs/rlog/rlog.1
@@ -0,0 +1,318 @@
+.de Id
+.ds Rv \\$3
+.ds Dt \\$4
+..
+.Id $FreeBSD$
+.ds i \&\s-1ISO\s0
+.ds r \&\s-1RCS\s0
+.ds u \&\s-1UTC\s0
+.if n .ds - \%--
+.if t .ds - \(em
+.TH RLOG 1 \*(Dt GNU
+.SH NAME
+rlog \- print log messages and other information about RCS files
+.SH SYNOPSIS
+.B rlog
+.RI [ " options " ] " file " .\|.\|.
+.SH DESCRIPTION
+.B rlog
+prints information about \*r files.
+.PP
+Pathnames matching an \*r suffix denote \*r files;
+all others denote working files.
+Names are paired as explained in
+.BR ci (1).
+.PP
+.B rlog
+prints the following information for each
+\*r file: \*r pathname, working pathname, head (i.e., the number
+of the latest revision on the trunk), default branch, access list, locks,
+symbolic names, suffix, total number of revisions,
+number of revisions selected for printing, and
+descriptive text.  This is followed by entries for the selected revisions in
+reverse chronological order for each branch.  For each revision,
+.B rlog
+prints revision number, author, date/time, state, number of
+lines added/deleted (with respect to the previous revision),
+locker of the revision (if any), and log message.
+All times are displayed in Coordinated Universal Time (\*u) by default;
+this can be overridden with
+.BR \-z .
+Without options,
+.B rlog
+prints complete information.
+The options below restrict this output.
+.nr n \w'\f3\-V\fP\f2n\fP'+2n-1/1n
+.ds n \nn
+.if \n(.g .if r an-tag-sep .ds n \w'\f3\-V\fP\f2n\fP'u+\n[an-tag-sep]u
+.TP \*n
+.B \-L
+Ignore \*r files that have no locks set.
+This is convenient in combination with
+.BR \-h ,
+.BR \-l ,
+and
+.BR \-R .
+.TP
+.B \-R
+Print only the name of the \*r file.
+This is convenient for translating a
+working pathname into an \*r pathname.
+.TP
+.BI \-v "[string]"
+Print only the working pathname and tip-revision.
+The optional string is prepended to the outputline.
+.TP
+.B \-h
+Print only the \*r pathname, working pathname, head,
+default branch, access list, locks,
+symbolic names, and suffix.
+.TP
+.B \-t
+Print the same as
+.BR \-h ,
+plus the descriptive text.
+.TP
+.B \-N
+Do not print the symbolic names.
+.TP
+.B \-b
+Print information about the revisions on the default branch, normally
+the highest branch on the trunk.
+.TP
+.BI \-d "dates"
+Print information about revisions with a checkin date/time in the ranges given by
+the semicolon-separated list of
+.IR dates .
+A range of the form
+.IB d1 < d2
+or
+.IB d2 > d1
+selects the revisions that were deposited between
+.I d1
+and
+.I d2
+exclusive.
+A range of the form
+.BI < d
+or
+.IB d >
+selects
+all revisions earlier than
+.IR d .
+A range of the form
+.IB d <
+or
+.BI > d
+selects
+all revisions dated later than
+.IR d .
+If
+.B <
+or
+.B >
+is followed by
+.B =
+then the ranges are inclusive, not exclusive.
+A range of the form
+.I d
+selects the single, latest revision dated
+.I d
+or earlier.
+The date/time strings
+.IR d ,
+.IR d1 ,
+and
+.I d2
+are in the free format explained in
+.BR co (1).
+Quoting is normally necessary, especially for
+.B <
+and
+.BR > .
+Note that the separator is
+a semicolon.
+.TP
+.BR \-l [\f2lockers\fP]
+Print information about locked revisions only.
+In addition, if the comma-separated list
+.I lockers
+of login names is given,
+ignore all locks other than those held by the
+.IR lockers .
+For example,
+.B "rlog\ \-L\ \-R\ \-lwft\ RCS/*"
+prints the name of \*r files locked by the user
+.BR wft .
+.TP
+.BR \-r [\f2revisions\fP]
+prints information about revisions given in the comma-separated list
+.I revisions
+of revisions and ranges.
+A range
+.IB rev1 : rev2
+means revisions
+.I rev1
+to
+.I rev2
+on the same branch,
+.BI : rev
+means revisions from the beginning of the branch up to and including
+.IR rev ,
+and
+.IB rev :
+means revisions starting with
+.I rev
+to the end of the branch containing
+.IR rev .
+An argument that is a branch means all
+revisions on that branch.
+A range of branches means all revisions
+on the branches in that range.
+A branch followed by a
+.B .\&
+means the latest revision in that branch.
+A bare
+.B \-r
+with no
+.I revisions
+means the latest revision on the default branch, normally the trunk.
+.TP
+.BI \-s states
+prints information about revisions whose state attributes match one of the
+states given in the comma-separated list
+.IR states .
+.TP
+.BR \-w [\f2logins\fP]
+prints information about revisions checked in by users with
+login names appearing in the comma-separated list
+.IR logins .
+If
+.I logins
+is omitted, the user's login is assumed.
+.TP
+.B \-T
+This option has no effect;
+it is present for compatibility with other \*r commands.
+.TP
+.BI \-V
+Print \*r's version number.
+.TP
+.BI \-V n
+Emulate \*r version
+.I n
+when generating logs.
+See
+.BR co (1)
+for more.
+.TP
+.BI \-x "suffixes"
+Use
+.I suffixes
+to characterize \*r files.
+See
+.BR ci (1)
+for details.
+.PP
+.B rlog
+prints the intersection of the revisions selected with
+the options
+.BR \-d ,
+.BR \-l ,
+.BR \-s ,
+and
+.BR \-w ,
+intersected
+with the union of the revisions selected by
+.B \-b
+and
+.BR \-r .
+.TP
+.BI \-z zone
+specifies the date output format,
+and specifies the default time zone for
+.I date
+in the
+.BI \-d dates
+option.
+The
+.I zone
+should be empty, a numeric \*u offset, or the special string
+.B LT
+for local time.
+The default is an empty
+.IR zone ,
+which uses the traditional \*r format of \*u without any time zone indication
+and with slashes separating the parts of the date;
+otherwise, times are output in \*i 8601 format with time zone indication.
+For example, if local time is January 11, 1990, 8pm Pacific Standard Time,
+eight hours west of \*u,
+then the time is output as follows:
+.RS
+.LP
+.RS
+.nf
+.ta \w'\f3\-z+05:30\fP  'u +\w'\f31990-01-11 09:30:00+05:30\fP  'u
+.ne 4
+\f2option\fP	\f2time output\fP
+\f3\-z\fP	\f31990/01/12 04:00:00\fP	\f2(default)\fP
+\f3\-zLT\fP	\f31990-01-11 20:00:00\-08\fP
+\f3\-z+05:30\fP	\f31990-01-12 09:30:00+05:30\fP
+.ta 4n +4n +4n +4n
+.fi
+.RE
+.SH EXAMPLES
+.LP
+.nf
+.B "    rlog  \-L  \-R  RCS/*"
+.B "    rlog  \-L  \-h  RCS/*"
+.B "    rlog  \-L  \-l  RCS/*"
+.B "    rlog  RCS/*"
+.fi
+.LP
+The first command prints the names of all \*r files in the subdirectory
+.B RCS
+that have locks.  The second command prints the headers of those files,
+and the third prints the headers plus the log messages of the locked revisions.
+The last command prints complete information.
+.SH ENVIRONMENT
+.TP
+.B \s-1RCSINIT\s0
+options prepended to the argument list, separated by spaces.
+See
+.BR ci (1)
+for details.
+.SH DIAGNOSTICS
+The exit status is zero if and only if all operations were successful.
+.SH IDENTIFICATION
+Author: Walter F. Tichy.
+.br
+Manual Page Revision: \*(Rv; Release Date: \*(Dt.
+.br
+Copyright \(co 1982, 1988, 1989 Walter F. Tichy.
+.br
+Copyright \(co 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert.
+.SH "SEE ALSO"
+ci(1), co(1), ident(1), rcs(1), rcsdiff(1), rcsintro(1), rcsmerge(1),
+rcsfile(5)
+.br
+Walter F. Tichy,
+\*r\*-A System for Version Control,
+.I "Software\*-Practice & Experience"
+.BR 15 ,
+7 (July 1985), 637-654.
+.SH BUGS
+The separator for revision ranges in the
+.B \-r
+option used to be
+.B \-
+instead of
+.BR : ,
+but this leads to confusion when symbolic names contain
+.BR \- .
+For backwards compatibility
+.B "rlog \-r"
+still supports the old
+.B \-
+separator, but it warns about this obsolete use.
+.br
diff --git a/gnu/usr.bin/rcs/rlog/rlog.c b/gnu/usr.bin/rcs/rlog/rlog.c
new file mode 100644
index 0000000000000..f8872febb971d
--- /dev/null
+++ b/gnu/usr.bin/rcs/rlog/rlog.c
@@ -0,0 +1,1290 @@
+/* Print log messages and other information about RCS files.  */
+
+/* Copyright 1982, 1988, 1989 Walter Tichy
+   Copyright 1990, 1991, 1992, 1993, 1994, 1995 Paul Eggert
+   Distributed under license by the Free Software Foundation, Inc.
+
+This file is part of RCS.
+
+RCS is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+RCS is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with RCS; see the file COPYING.
+If not, write to the Free Software Foundation,
+59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+Report problems and direct all questions to:
+
+    rcs-bugs@cs.purdue.edu
+
+*/
+
+/*
+ * Revision 5.18  1995/06/16 06:19:24  eggert
+ * Update FSF address.
+ *
+ * Revision 5.17  1995/06/01 16:23:43  eggert
+ * (struct rcslockers): Renamed from `struct lockers'.
+ * (getnumericrev): Return error indication instead of ignoring errors.
+ * (main): Check it.  Don't use dateform.
+ * (recentdate, extdate): cmpnum -> cmpdate
+ *
+ * Revision 5.16  1994/04/13 16:30:34  eggert
+ * Fix bug; `rlog -lxxx' inverted the sense of -l.
+ *
+ * Revision 5.15  1994/03/17 14:05:48  eggert
+ * -d'<DATE' now excludes DATE; the new syntax -d'<=DATE' includes it.
+ * Emulate -V4's white space generation more precisely.
+ * Work around SVR4 stdio performance bug.  Remove lint.
+ *
+ * Revision 5.14  1993/11/09 17:40:15  eggert
+ * -V now prints version on stdout and exits.
+ *
+ * Revision 5.13  1993/11/03 17:42:27  eggert
+ * Add -N, -z.  Ignore -T.
+ *
+ * Revision 5.12  1992/07/28  16:12:44  eggert
+ * Don't miss B.0 when handling branch B.  Diagnose missing `,' in -r.
+ * Add -V.  Avoid `unsigned'.  Statement macro names now end in _.
+ *
+ * Revision 5.11  1992/01/24  18:44:19  eggert
+ * Don't duplicate unexpected_EOF's function.  lint -> RCS_lint
+ *
+ * Revision 5.10  1992/01/06  02:42:34  eggert
+ * Update usage string.
+ * while (E) ; -> while (E) continue;
+ *
+ * Revision 5.9  1991/09/17  19:07:40  eggert
+ * Getscript() didn't uncache partial lines.
+ *
+ * Revision 5.8  1991/08/19  03:13:55  eggert
+ * Revision separator is `:', not `-'.
+ * Check for missing and duplicate logs.  Tune.
+ * Permit log messages that do not end in newline (including empty logs).
+ *
+ * Revision 5.7  1991/04/21  11:58:31  eggert
+ * Add -x, RCSINIT, MS-DOS support.
+ *
+ * Revision 5.6  1991/02/26  17:07:17  eggert
+ * Survive RCS files with missing logs.
+ * strsave -> str_save (DG/UX name clash)
+ *
+ * Revision 5.5  1990/11/01  05:03:55  eggert
+ * Permit arbitrary data in logs and comment leaders.
+ *
+ * Revision 5.4  1990/10/04  06:30:22  eggert
+ * Accumulate exit status across files.
+ *
+ * Revision 5.3  1990/09/11  02:41:16  eggert
+ * Plug memory leak.
+ *
+ * Revision 5.2  1990/09/04  08:02:33  eggert
+ * Count RCS lines better.
+ *
+ * Revision 5.0  1990/08/22  08:13:48  eggert
+ * Remove compile-time limits; use malloc instead.  Add setuid support.
+ * Switch to GMT.
+ * Report dates in long form, to warn about dates past 1999/12/31.
+ * Change "added/del" message to make room for the longer dates.
+ * Don't generate trailing white space.  Add -V.  Ansify and Posixate.
+ *
+ * Revision 4.7  89/05/01  15:13:48  narten
+ * changed copyright header to reflect current distribution rules
+ *
+ * Revision 4.6  88/08/09  19:13:28  eggert
+ * Check for memory exhaustion; don't access freed storage.
+ * Shrink stdio code size; remove lint.
+ *
+ * Revision 4.5  87/12/18  11:46:38  narten
+ * more lint cleanups (Guy Harris)
+ *
+ * Revision 4.4  87/10/18  10:41:12  narten
+ * Updating version numbers
+ * Changes relative to 1.1 actually relative to 4.2
+ *
+ * Revision 1.3  87/09/24  14:01:10  narten
+ * Sources now pass through lint (if you ignore printf/sprintf/fprintf
+ * warnings)
+ *
+ * Revision 1.2  87/03/27  14:22:45  jenkins
+ * Port to suns
+ *
+ * Revision 4.2  83/12/05  09:18:09  wft
+ * changed rewriteflag to external.
+ *
+ * Revision 4.1  83/05/11  16:16:55  wft
+ * Added -b, updated getnumericrev() accordingly.
+ * Replaced getpwuid() with getcaller().
+ *
+ * Revision 3.7  83/05/11  14:24:13  wft
+ * Added options -L and -R;
+ * Fixed selection bug with -l on multiple files.
+ * Fixed error on dates of the form -d'>date' (rewrote getdatepair()).
+ *
+ * Revision 3.6  82/12/24  15:57:53  wft
+ * shortened output format.
+ *
+ * Revision 3.5  82/12/08  21:45:26  wft
+ * removed call to checkaccesslist(); used DATEFORM to format all dates;
+ * removed unused variables.
+ *
+ * Revision 3.4  82/12/04  13:26:25  wft
+ * Replaced getdelta() with gettree(); removed updating of field lockedby.
+ *
+ * Revision 3.3  82/12/03  14:08:20  wft
+ * Replaced getlogin with getpwuid(), %02d with %.2d, fancydate with PRINTDATE.
+ * Fixed printing of nil, removed printing of Suffix,
+ * added shortcut if no revisions are printed, disambiguated struct members.
+ *
+ * Revision 3.2  82/10/18  21:09:06  wft
+ * call to curdir replaced with getfullRCSname(),
+ * fixed call to getlogin(), cosmetic changes on output,
+ * changed conflicting long identifiers.
+ *
+ * Revision 3.1  82/10/13  16:07:56  wft
+ * fixed type of variables receiving from getc() (char -> int).
+ */
+
+
+
+#include "rcsbase.h"
+
+struct rcslockers {                   /* lockers in locker option; stored   */
+     char const		* login;      /* lockerlist			    */
+     struct rcslockers  * lockerlink;
+     }  ;
+
+struct  stateattri {                  /* states in state option; stored in  */
+     char const		* status;     /* statelist			    */
+     struct  stateattri * nextstate;
+     }  ;
+
+struct  authors {                     /* login names in author option;      */
+     char const		* login;      /* stored in authorlist		    */
+     struct     authors * nextauthor;
+     }  ;
+
+struct Revpairs{                      /* revision or branch range in -r     */
+     int		  numfld;     /* option; stored in revlist	    */
+     char const		* strtrev;
+     char const		* endrev;
+     struct  Revpairs   * rnext;
+     } ;
+
+struct Datepairs{                     /* date range in -d option; stored in */
+     struct Datepairs *dnext;
+     char               strtdate[datesize];   /* duelst and datelist      */
+     char               enddate[datesize];
+     char ne_date; /* datelist only; distinguishes < from <= */
+     };
+
+static char extractdelta P((struct hshentry const*));
+static int checkrevpair P((char const*,char const*));
+static int extdate P((struct hshentry*));
+static int getnumericrev P((void));
+static struct hshentry const *readdeltalog P((void));
+static void cleanup P((void));
+static void exttree P((struct hshentry*));
+static void getauthor P((char*));
+static void getdatepair P((char*));
+static void getlocker P((char*));
+static void getrevpairs P((char*));
+static void getscript P((struct hshentry*));
+static void getstate P((char*));
+static void putabranch P((struct hshentry const*));
+static void putadelta P((struct hshentry const*,struct hshentry const*,int));
+static void putforest P((struct branchhead const*));
+static void putree P((struct hshentry const*));
+static void putrunk P((void));
+static void recentdate P((struct hshentry const*,struct Datepairs*));
+static void trunclocks P((void));
+
+static char const *insDelFormat;
+static int branchflag;	/*set on -b */
+static int exitstatus;
+static int lockflag;
+static struct Datepairs *datelist, *duelst;
+static struct Revpairs *revlist, *Revlst;
+static struct authors *authorlist;
+static struct rcslockers *lockerlist;
+static struct stateattri *statelist;
+
+
+mainProg(rlogId, "rlog", "$FreeBSD$")
+{
+	static char const cmdusage[] =
+		"\nrlog usage: rlog -{bhLNRt} -v[string] -ddates -l[lockers] -r[revs] -sstates -Vn -w[logins] -xsuff -zzone file ...";
+
+	register FILE *out;
+	char *a, **newargv;
+	struct Datepairs *currdate;
+	char const *accessListString, *accessFormat;
+	char const *headFormat, *symbolFormat;
+	struct access const *curaccess;
+	struct assoc const *curassoc;
+	struct hshentry const *delta;
+	struct rcslock const *currlock;
+	int descflag, selectflag;
+	int onlylockflag;  /* print only files with locks */
+	int onlyRCSflag;  /* print only RCS pathname */
+	int pre5;
+	int shownames;
+	int revno;
+	int versionlist;
+	char *vstring;
+
+        descflag = selectflag = shownames = true;
+	versionlist = onlylockflag = onlyRCSflag = false;
+	vstring=0;
+	out = stdout;
+	suffixes = X_DEFAULT;
+
+	argc = getRCSINIT(argc, argv, &newargv);
+	argv = newargv;
+	while (a = *++argv,  0<--argc && *a++=='-') {
+		switch (*a++) {
+
+		case 'L':
+			onlylockflag = true;
+			break;
+
+		case 'N':
+			shownames = false;
+			break;
+
+		case 'R':
+			onlyRCSflag =true;
+			break;
+
+                case 'l':
+                        lockflag = true;
+			getlocker(a);
+                        break;
+
+                case 'b':
+                        branchflag = true;
+                        break;
+
+                case 'r':
+			getrevpairs(a);
+                        break;
+
+                case 'd':
+			getdatepair(a);
+                        break;
+
+                case 's':
+			getstate(a);
+                        break;
+
+                case 'w':
+			getauthor(a);
+                        break;
+
+                case 'h':
+			descflag = false;
+                        break;
+
+                case 't':
+                        selectflag = false;
+                        break;
+
+		case 'q':
+			/* This has no effect; it's here for consistency.  */
+			quietflag = true;
+			break;
+
+		case 'x':
+			suffixes = a;
+			break;
+
+		case 'z':
+			zone_set(a);
+			break;
+
+		case 'T':
+			/* Ignore -T, so that RCSINIT can contain -T.  */
+			if (*a)
+				goto unknown;
+			break;
+
+		case 'V':
+			setRCSversion(*argv);
+			break;
+
+		case 'v':
+			versionlist = true;
+			vstring = a;
+			break;
+
+                default:
+		unknown:
+			error("unknown option: %s%s", *argv, cmdusage);
+
+                };
+        } /* end of option processing */
+
+	if (! (descflag|selectflag)) {
+		warn("-t overrides -h.");
+		descflag = true;
+	}
+
+	pre5 = RCSversion < VERSION(5);
+	if (pre5) {
+	    accessListString = "\naccess list:   ";
+	    accessFormat = "  %s";
+	    headFormat = "RCS file:        %s;   Working file:    %s\nhead:           %s%s\nbranch:         %s%s\nlocks:         ";
+	    insDelFormat = "  lines added/del: %ld/%ld";
+	    symbolFormat = "  %s: %s;";
+	} else {
+	    accessListString = "\naccess list:";
+	    accessFormat = "\n\t%s";
+	    headFormat = "RCS file: %s\nWorking file: %s\nhead:%s%s\nbranch:%s%s\nlocks:%s";
+	    insDelFormat = "  lines: +%ld -%ld";
+	    symbolFormat = "\n\t%s: %s";
+	}
+
+	/* Now handle all pathnames.  */
+	if (nerror)
+	  cleanup();
+	else if (argc < 1)
+	  faterror("no input file%s", cmdusage);
+	else
+	  for (;  0 < argc;  cleanup(), ++argv, --argc) {
+	    ffree();
+
+	    if (pairnames(argc, argv, rcsreadopen, true, false)  <=  0)
+		continue;
+
+	    /*
+	     * RCSname contains the name of the RCS file,
+	     * and finptr the file descriptor;
+	     * workname contains the name of the working file.
+             */
+
+	    /* Keep only those locks given by -l.  */
+	    if (lockflag)
+		trunclocks();
+
+            /* do nothing if -L is given and there are no locks*/
+	    if (onlylockflag && !Locks)
+		continue;
+
+	    if ( versionlist ) {
+		gettree();
+		aprintf(out, "%s%s %s\n", vstring, workname, tiprev());
+		continue;
+	    }
+
+	    if ( onlyRCSflag ) {
+		aprintf(out, "%s\n", RCSname);
+		continue;
+	    }
+
+	    gettree();
+
+	    if (!getnumericrev())
+		continue;
+
+	    /*
+	    * Output the first character with putc, not printf.
+	    * Otherwise, an SVR4 stdio bug buffers output inefficiently.
+	    */
+	    aputc_('\n', out)
+
+	    /*   print RCS pathname, working pathname and optional
+                 administrative information                         */
+            /* could use getfullRCSname() here, but that is very slow */
+	    aprintf(out, headFormat, RCSname, workname,
+		    Head ? " " : "",  Head ? Head->num : "",
+		    Dbranch ? " " : "",  Dbranch ? Dbranch : "",
+		    StrictLocks ? " strict" : ""
+	    );
+            currlock = Locks;
+            while( currlock ) {
+		aprintf(out, symbolFormat, currlock->login,
+                                currlock->delta->num);
+                currlock = currlock->nextlock;
+            }
+            if (StrictLocks && pre5)
+                aputs("  ;  strict" + (Locks?3:0), out);
+
+	    aputs(accessListString, out);      /*  print access list  */
+            curaccess = AccessList;
+            while(curaccess) {
+		aprintf(out, accessFormat, curaccess->login);
+                curaccess = curaccess->nextaccess;
+            }
+
+	    if (shownames) {
+		aputs("\nsymbolic names:", out);   /*  print symbolic names   */
+		for (curassoc=Symbols; curassoc; curassoc=curassoc->nextassoc)
+		    aprintf(out, symbolFormat, curassoc->symbol, curassoc->num);
+	    }
+	    if (pre5) {
+		aputs("\ncomment leader:  \"", out);
+		awrite(Comment.string, Comment.size, out);
+		afputc('\"', out);
+	    }
+	    if (!pre5  ||  Expand != KEYVAL_EXPAND)
+		aprintf(out, "\nkeyword substitution: %s",
+			expand_names[Expand]
+		);
+
+	    aprintf(out, "\ntotal revisions: %d", TotalDeltas);
+
+	    revno = 0;
+
+	    if (Head  &&  selectflag & descflag) {
+
+		exttree(Head);
+
+		/*  get most recently date of the dates pointed by duelst  */
+		currdate = duelst;
+		while( currdate) {
+		    VOID strcpy(currdate->strtdate, "0.0.0.0.0.0");
+		    recentdate(Head, currdate);
+		    currdate = currdate->dnext;
+		}
+
+		revno = extdate(Head);
+
+		aprintf(out, ";\tselected revisions: %d", revno);
+	    }
+
+	    afputc('\n',out);
+	    if (descflag) {
+		aputs("description:\n", out);
+		getdesc(true);
+	    }
+	    if (revno) {
+		while (! (delta = readdeltalog())->selector  ||  --revno)
+		    continue;
+		if (delta->next && countnumflds(delta->num)==2)
+		    /* Read through delta->next to get its insertlns.  */
+		    while (readdeltalog() != delta->next)
+			continue;
+		putrunk();
+		putree(Head);
+	    }
+	    aputs("----------------------------\n", out);
+	    aputs("=============================================================================\n",out);
+	  }
+	Ofclose(out);
+	exitmain(exitstatus);
+}
+
+	static void
+cleanup()
+{
+	if (nerror) exitstatus = EXIT_FAILURE;
+	Izclose(&finptr);
+}
+
+#if RCS_lint
+#	define exiterr rlogExit
+#endif
+	void
+exiterr()
+{
+	_exit(EXIT_FAILURE);
+}
+
+
+
+	static void
+putrunk()
+/*  function:  print revisions chosen, which are in trunk      */
+
+{
+	register struct hshentry const *ptr;
+
+	for (ptr = Head;  ptr;  ptr = ptr->next)
+		putadelta(ptr, ptr->next, true);
+}
+
+
+
+	static void
+putree(root)
+	struct hshentry const *root;
+/*   function: print delta tree (not including trunk) in reverse
+               order on each branch                                        */
+
+{
+	if (!root) return;
+
+        putree(root->next);
+
+        putforest(root->branches);
+}
+
+
+
+
+	static void
+putforest(branchroot)
+	struct branchhead const *branchroot;
+/*   function:  print branches that has the same direct ancestor    */
+{
+	if (!branchroot) return;
+
+        putforest(branchroot->nextbranch);
+
+        putabranch(branchroot->hsh);
+        putree(branchroot->hsh);
+}
+
+
+
+
+	static void
+putabranch(root)
+	struct hshentry const *root;
+/*   function  :  print one branch     */
+
+{
+	if (!root) return;
+
+        putabranch(root->next);
+
+        putadelta(root, root, false);
+}
+
+
+
+
+
+	static void
+putadelta(node,editscript,trunk)
+	register struct hshentry const *node, *editscript;
+	int trunk;
+/*  function: Print delta node if node->selector is set.        */
+/*      editscript indicates where the editscript is stored     */
+/*      trunk indicated whether this node is in trunk           */
+{
+	static char emptych[] = EMPTYLOG;
+
+	register FILE *out;
+	char const *s;
+	size_t n;
+	struct branchhead const *newbranch;
+	struct buf branchnum;
+	char datebuf[datesize + zonelenmax];
+	int pre5 = RCSversion < VERSION(5);
+
+	if (!node->selector)
+            return;
+
+	out = stdout;
+	aprintf(out,
+		"----------------------------\nrevision %s%s",
+		node->num,  pre5 ? "        " : ""
+	);
+        if ( node->lockedby )
+	    aprintf(out, pre5+"\tlocked by: %s;", node->lockedby);
+
+	aprintf(out, "\ndate: %s;  author: %s;  state: %s;",
+		date2str(node->date, datebuf),
+		node->author, node->state
+	);
+
+        if ( editscript )
+           if(trunk)
+	      aprintf(out, insDelFormat,
+                             editscript->deletelns, editscript->insertlns);
+           else
+	      aprintf(out, insDelFormat,
+                             editscript->insertlns, editscript->deletelns);
+
+        newbranch = node->branches;
+        if ( newbranch ) {
+	   bufautobegin(&branchnum);
+	   aputs("\nbranches:", out);
+           while( newbranch ) {
+		getbranchno(newbranch->hsh->num, &branchnum);
+		aprintf(out, "  %s;", branchnum.string);
+                newbranch = newbranch->nextbranch;
+           }
+	   bufautoend(&branchnum);
+        }
+
+	afputc('\n', out);
+	s = node->log.string;
+	if (!(n = node->log.size)) {
+		s = emptych;
+		n = sizeof(emptych)-1;
+	}
+	awrite(s, n, out);
+	if (s[n-1] != '\n')
+		afputc('\n', out);
+}
+
+
+	static struct hshentry const *
+readdeltalog()
+/*  Function : get the log message and skip the text of a deltatext node.
+ *	       Return the delta found.
+ *             Assumes the current lexeme is not yet in nexttok; does not
+ *             advance nexttok.
+ */
+{
+        register struct  hshentry  * Delta;
+	struct buf logbuf;
+	struct cbuf cb;
+
+	if (eoflex())
+		fatserror("missing delta log");
+        nextlex();
+	if (!(Delta = getnum()))
+		fatserror("delta number corrupted");
+	getkeystring(Klog);
+	if (Delta->log.string)
+		fatserror("duplicate delta log");
+	bufautobegin(&logbuf);
+	cb = savestring(&logbuf);
+	Delta->log = bufremember(&logbuf, cb.size);
+
+	ignorephrases(Ktext);
+	getkeystring(Ktext);
+        Delta->insertlns = Delta->deletelns = 0;
+        if ( Delta != Head)
+                getscript(Delta);
+        else
+                readstring();
+	return Delta;
+}
+
+
+	static void
+getscript(Delta)
+struct    hshentry   * Delta;
+/*   function:  read edit script of Delta and count how many lines added  */
+/*              and deleted in the script                                 */
+
+{
+        int ed;   /*  editor command  */
+	declarecache;
+	register RILE *fin;
+        register  int   c;
+	register long i;
+	struct diffcmd dc;
+
+	fin = finptr;
+	setupcache(fin);
+	initdiffcmd(&dc);
+	while (0  <=  (ed = getdiffcmd(fin,true,(FILE *)0,&dc)))
+	    if (!ed)
+                 Delta->deletelns += dc.nlines;
+	    else {
+                 /*  skip scripted lines  */
+		 i = dc.nlines;
+		 Delta->insertlns += i;
+		 cache(fin);
+		 do {
+		     for (;;) {
+			cacheget_(c)
+			switch (c) {
+			    default:
+				continue;
+			    case SDELIM:
+				cacheget_(c)
+				if (c == SDELIM)
+				    continue;
+				if (--i)
+					unexpected_EOF();
+				nextc = c;
+				uncache(fin);
+				return;
+			    case '\n':
+				break;
+			}
+			break;
+		     }
+		     ++rcsline;
+		 } while (--i);
+		 uncache(fin);
+            }
+}
+
+
+
+
+
+
+
+	static void
+exttree(root)
+struct hshentry  *root;
+/*  function: select revisions , starting with root             */
+
+{
+	struct branchhead const *newbranch;
+
+	if (!root) return;
+
+	root->selector = extractdelta(root);
+	root->log.string = 0;
+        exttree(root->next);
+
+        newbranch = root->branches;
+        while( newbranch ) {
+            exttree(newbranch->hsh);
+            newbranch = newbranch->nextbranch;
+        }
+}
+
+
+
+
+	static void
+getlocker(argv)
+char    * argv;
+/*   function : get the login names of lockers from command line   */
+/*              and store in lockerlist.                           */
+
+{
+        register char c;
+	struct rcslockers *newlocker;
+        argv--;
+	while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+	    continue;
+        if (  c == '\0') {
+	    lockerlist = 0;
+            return;
+        }
+
+        while( c != '\0' ) {
+	    newlocker = talloc(struct rcslockers);
+            newlocker->lockerlink = lockerlist;
+            newlocker->login = argv;
+            lockerlist = newlocker;
+	    while ((c = *++argv) && c!=',' && c!=' ' && c!='\t' && c!='\n' && c!=';')
+		continue;
+            *argv = '\0';
+            if ( c == '\0' ) return;
+	    while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+		continue;
+        }
+}
+
+
+
+	static void
+getauthor(argv)
+char   *argv;
+/*   function:  get the author's name from command line   */
+/*              and store in authorlist                   */
+
+{
+        register    c;
+        struct     authors  * newauthor;
+
+        argv--;
+	while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+	    continue;
+        if ( c == '\0' ) {
+	    authorlist = talloc(struct authors);
+	    authorlist->login = getusername(false);
+	    authorlist->nextauthor = 0;
+            return;
+        }
+
+        while( c != '\0' ) {
+	    newauthor = talloc(struct authors);
+            newauthor->nextauthor = authorlist;
+            newauthor->login = argv;
+            authorlist = newauthor;
+	    while ((c = *++argv) && c!=',' && c!=' ' && c!='\t' && c!='\n' && c!=';')
+		continue;
+            * argv = '\0';
+            if ( c == '\0') return;
+	    while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+		continue;
+        }
+}
+
+
+
+
+	static void
+getstate(argv)
+char   * argv;
+/*   function :  get the states of revisions from command line  */
+/*               and store in statelist                         */
+
+{
+        register  char  c;
+        struct    stateattri    *newstate;
+
+        argv--;
+	while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+	    continue;
+        if ( c == '\0'){
+	    error("missing state attributes after -s options");
+            return;
+        }
+
+        while( c != '\0' ) {
+	    newstate = talloc(struct stateattri);
+            newstate->nextstate = statelist;
+            newstate->status = argv;
+            statelist = newstate;
+	    while ((c = *++argv) && c!=',' && c!=' ' && c!='\t' && c!='\n' && c!=';')
+		continue;
+            *argv = '\0';
+            if ( c == '\0' ) return;
+	    while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+		continue;
+        }
+}
+
+
+
+	static void
+trunclocks()
+/*  Function:  Truncate the list of locks to those that are held by the  */
+/*             id's on lockerlist. Do not truncate if lockerlist empty.  */
+
+{
+	struct rcslockers const *plocker;
+	struct rcslock *p, **pp;
+
+	if (!lockerlist) return;
+
+        /* shorten Locks to those contained in lockerlist */
+	for (pp = &Locks;  (p = *pp);  )
+	    for (plocker = lockerlist;  ;  )
+		if (strcmp(plocker->login, p->login) == 0) {
+		    pp = &p->nextlock;
+		    break;
+		} else if (!(plocker = plocker->lockerlink)) {
+		    *pp = p->nextlock;
+		    break;
+		}
+}
+
+
+
+	static void
+recentdate(root, pd)
+	struct hshentry const *root;
+	struct Datepairs *pd;
+/*  function:  Finds the delta that is closest to the cutoff date given by   */
+/*             pd among the revisions selected by exttree.                   */
+/*             Successively narrows down the interval given by pd,           */
+/*             and sets the strtdate of pd to the date of the selected delta */
+{
+	struct branchhead const *newbranch;
+
+	if (!root) return;
+	if (root->selector) {
+	     if ( cmpdate(root->date, pd->strtdate) >= 0 &&
+		  cmpdate(root->date, pd->enddate) <= 0)
+		VOID strcpy(pd->strtdate, root->date);
+        }
+
+        recentdate(root->next, pd);
+        newbranch = root->branches;
+        while( newbranch) {
+           recentdate(newbranch->hsh, pd);
+           newbranch = newbranch->nextbranch;
+	}
+}
+
+
+
+
+
+
+	static int
+extdate(root)
+struct  hshentry        * root;
+/*  function:  select revisions which are in the date range specified     */
+/*             in duelst  and datelist, start at root                     */
+/* Yield number of revisions selected, including those already selected.  */
+{
+	struct branchhead const *newbranch;
+	struct Datepairs const *pdate;
+	int revno, ne;
+
+	if (!root)
+	    return 0;
+
+        if ( datelist || duelst) {
+            pdate = datelist;
+            while( pdate ) {
+		ne = pdate->ne_date;
+		if (
+			(!pdate->strtdate[0]
+			|| ne <= cmpdate(root->date, pdate->strtdate))
+		    &&
+			(!pdate->enddate[0]
+			|| ne <= cmpdate(pdate->enddate, root->date))
+		)
+                        break;
+                pdate = pdate->dnext;
+            }
+	    if (!pdate) {
+                pdate = duelst;
+		for (;;) {
+		   if (!pdate) {
+			root->selector = false;
+			break;
+		   }
+		   if (cmpdate(root->date, pdate->strtdate) == 0)
+                      break;
+                   pdate = pdate->dnext;
+                }
+            }
+        }
+	revno = root->selector + extdate(root->next);
+
+        newbranch = root->branches;
+        while( newbranch ) {
+	   revno += extdate(newbranch->hsh);
+           newbranch = newbranch->nextbranch;
+        }
+	return revno;
+}
+
+
+
+	static char
+extractdelta(pdelta)
+	struct hshentry const *pdelta;
+/*  function:  compare information of pdelta to the authorlist, lockerlist,*/
+/*             statelist, revlist and yield true if pdelta is selected.    */
+
+{
+	struct rcslock const *plock;
+	struct stateattri const *pstate;
+	struct authors const *pauthor;
+	struct Revpairs const *prevision;
+	int length;
+
+	if ((pauthor = authorlist)) /* only certain authors wanted */
+	    while (strcmp(pauthor->login, pdelta->author) != 0)
+		if (!(pauthor = pauthor->nextauthor))
+		    return false;
+	if ((pstate = statelist)) /* only certain states wanted */
+	    while (strcmp(pstate->status, pdelta->state) != 0)
+		if (!(pstate = pstate->nextstate))
+		    return false;
+	if (lockflag) /* only locked revisions wanted */
+	    for (plock = Locks;  ;  plock = plock->nextlock)
+		if (!plock)
+		    return false;
+		else if (plock->delta == pdelta)
+		    break;
+	if ((prevision = Revlst)) /* only certain revs or branches wanted */
+	    for (;;) {
+                length = prevision->numfld;
+		if (
+		    countnumflds(pdelta->num) == length+(length&1) &&
+		    0 <= compartial(pdelta->num, prevision->strtrev, length) &&
+		    0 <= compartial(prevision->endrev, pdelta->num, length)
+		)
+		     break;
+		if (!(prevision = prevision->rnext))
+		    return false;
+            }
+	return true;
+}
+
+
+
+	static void
+getdatepair(argv)
+   char   * argv;
+/*  function:  get time range from command line and store in datelist if    */
+/*             a time range specified or in duelst if a time spot specified */
+
+{
+        register   char         c;
+        struct     Datepairs    * nextdate;
+	char const		* rawdate;
+	int                     switchflag;
+
+        argv--;
+	while ((c = *++argv)==',' || c==' ' || c=='\t' || c=='\n' || c==';')
+	    continue;
+        if ( c == '\0' ) {
+	    error("missing date/time after -d");
+            return;
+        }
+
+        while( c != '\0' )  {
+	    switchflag = false;
+	    nextdate = talloc(struct Datepairs);
+            if ( c == '<' ) {   /*   case: -d <date   */
+                c = *++argv;
+		if (!(nextdate->ne_date = c!='='))
+		    c = *++argv;
+                (nextdate->strtdate)[0] = '\0';
+	    } else if (c == '>') { /* case: -d'>date' */
+		c = *++argv;
+		if (!(nextdate->ne_date = c!='='))
+		    c = *++argv;
+		(nextdate->enddate)[0] = '\0';
+		switchflag = true;
+	    } else {
+                rawdate = argv;
+		while( c != '<' && c != '>' && c != ';' && c != '\0')
+		     c = *++argv;
+                *argv = '\0';
+		if ( c == '>' ) switchflag=true;
+		str2date(rawdate,
+			 switchflag ? nextdate->enddate : nextdate->strtdate);
+		if ( c == ';' || c == '\0') {  /*  case: -d date  */
+		    VOID strcpy(nextdate->enddate,nextdate->strtdate);
+                    nextdate->dnext = duelst;
+                    duelst = nextdate;
+		    goto end;
+		} else {
+		    /*   case:   -d date<  or -d  date>; see switchflag */
+		    int eq = argv[1]=='=';
+		    nextdate->ne_date = !eq;
+		    argv += eq;
+		    while ((c = *++argv) == ' ' || c=='\t' || c=='\n')
+			continue;
+		    if ( c == ';' || c == '\0') {
+			/* second date missing */
+			if (switchflag)
+			    *nextdate->strtdate= '\0';
+			else
+			    *nextdate->enddate= '\0';
+			nextdate->dnext = datelist;
+			datelist = nextdate;
+			goto end;
+		    }
+                }
+            }
+            rawdate = argv;
+	    while( c != '>' && c != '<' && c != ';' && c != '\0')
+ 		c = *++argv;
+            *argv = '\0';
+	    str2date(rawdate,
+		     switchflag ? nextdate->strtdate : nextdate->enddate);
+            nextdate->dnext = datelist;
+	    datelist = nextdate;
+     end:
+	    if (RCSversion < VERSION(5))
+		nextdate->ne_date = 0;
+	    if ( c == '\0')  return;
+	    while ((c = *++argv) == ';' || c == ' ' || c == '\t' || c =='\n')
+		continue;
+        }
+}
+
+
+
+	static int
+getnumericrev()
+/*  function:  get the numeric name of revisions which stored in revlist  */
+/*             and then stored the numeric names in Revlst                */
+/*             if branchflag, also add default branch                     */
+
+{
+        struct  Revpairs        * ptr, *pt;
+	int n;
+	struct buf s, e;
+	char const *lrev;
+	struct buf const *rstart, *rend;
+
+	Revlst = 0;
+        ptr = revlist;
+	bufautobegin(&s);
+	bufautobegin(&e);
+        while( ptr ) {
+	    n = 0;
+	    rstart = &s;
+	    rend = &e;
+
+	    switch (ptr->numfld) {
+
+	      case 1: /* -rREV */
+		if (!expandsym(ptr->strtrev, &s))
+		    goto freebufs;
+		rend = &s;
+		n = countnumflds(s.string);
+		if (!n  &&  (lrev = tiprev())) {
+		    bufscpy(&s, lrev);
+		    n = countnumflds(lrev);
+		}
+		break;
+
+	      case 2: /* -rREV: */
+		if (!expandsym(ptr->strtrev, &s))
+		    goto freebufs;
+		bufscpy(&e, s.string);
+		n = countnumflds(s.string);
+		(n<2 ? e.string : strrchr(e.string,'.'))[0]  =  0;
+		break;
+
+	      case 3: /* -r:REV */
+		if (!expandsym(ptr->endrev, &e))
+		    goto freebufs;
+		if ((n = countnumflds(e.string)) < 2)
+		    bufscpy(&s, ".0");
+		else {
+		    bufscpy(&s, e.string);
+		    VOID strcpy(strrchr(s.string,'.'), ".0");
+		}
+		break;
+
+	      default: /* -rREV1:REV2 */
+		if (!(
+			expandsym(ptr->strtrev, &s)
+		    &&	expandsym(ptr->endrev, &e)
+		    &&	checkrevpair(s.string, e.string)
+		))
+		    goto freebufs;
+		n = countnumflds(s.string);
+		/* Swap if out of order.  */
+		if (compartial(s.string,e.string,n) > 0) {
+		    rstart = &e;
+		    rend = &s;
+		}
+		break;
+	    }
+
+	    if (n) {
+		pt = ftalloc(struct Revpairs);
+		pt->numfld = n;
+		pt->strtrev = fstr_save(rstart->string);
+		pt->endrev = fstr_save(rend->string);
+                pt->rnext = Revlst;
+                Revlst = pt;
+	    }
+	    ptr = ptr->rnext;
+        }
+        /* Now take care of branchflag */
+	if (branchflag && (Dbranch||Head)) {
+	    pt = ftalloc(struct Revpairs);
+	    pt->strtrev = pt->endrev =
+		Dbranch ? Dbranch : fstr_save(partialno(&s,Head->num,1));
+	    pt->rnext=Revlst; Revlst=pt;
+	    pt->numfld = countnumflds(pt->strtrev);
+        }
+
+      freebufs:
+	bufautoend(&s);
+	bufautoend(&e);
+	return !ptr;
+}
+
+
+
+	static int
+checkrevpair(num1,num2)
+	char const *num1, *num2;
+/*  function:  check whether num1, num2 are legal pair,i.e.
+    only the last field are different and have same number of
+    fields( if length <= 2, may be different if first field)   */
+
+{
+	int length = countnumflds(num1);
+
+	if (
+			countnumflds(num2) != length
+		||	(2 < length  &&  compartial(num1, num2, length-1) != 0)
+	) {
+	    rcserror("invalid branch or revision pair %s : %s", num1, num2);
+            return false;
+        }
+
+        return true;
+}
+
+
+
+	static void
+getrevpairs(argv)
+register     char    * argv;
+/*  function:  get revision or branch range from command line, and   */
+/*             store in revlist                                      */
+
+{
+        register    char    c;
+        struct      Revpairs  * nextrevpair;
+	int separator;
+
+	c = *argv;
+
+	/* Support old ambiguous '-' syntax; this will go away.  */
+	if (strchr(argv,':'))
+	    separator = ':';
+	else {
+	    if (strchr(argv,'-')  &&  VERSION(5) <= RCSversion)
+		warn("`-' is obsolete in `-r%s'; use `:' instead", argv);
+	    separator = '-';
+	}
+
+	for (;;) {
+	    while (c==' ' || c=='\t' || c=='\n')
+		c = *++argv;
+	    nextrevpair = talloc(struct Revpairs);
+            nextrevpair->rnext = revlist;
+            revlist = nextrevpair;
+	    nextrevpair->numfld = 1;
+	    nextrevpair->strtrev = argv;
+	    for (;;  c = *++argv) {
+		switch (c) {
+		    default:
+			continue;
+		    case '\0': case ' ': case '\t': case '\n':
+		    case ',': case ';':
+			break;
+		    case ':': case '-':
+			if (c == separator)
+			    break;
+			continue;
+		}
+		break;
+	    }
+	    *argv = '\0';
+	    while (c==' ' || c=='\t' || c=='\n')
+		c = *++argv;
+	    if (c == separator) {
+		while ((c = *++argv) == ' ' || c == '\t' || c =='\n')
+		    continue;
+		nextrevpair->endrev = argv;
+		for (;;  c = *++argv) {
+		    switch (c) {
+			default:
+			    continue;
+			case '\0': case ' ': case '\t': case '\n':
+			case ',': case ';':
+			    break;
+			case ':': case '-':
+			    if (c == separator)
+				break;
+			    continue;
+		    }
+		    break;
+		}
+		*argv = '\0';
+		while (c==' ' || c=='\t' || c =='\n')
+		    c = *++argv;
+		nextrevpair->numfld =
+		    !nextrevpair->endrev[0] ? 2 /* -rREV: */ :
+		    !nextrevpair->strtrev[0] ? 3 /* -r:REV */ :
+		    4 /* -rREV1:REV2 */;
+            }
+	    if (!c)
+		break;
+	    else if (c==',' || c==';')
+		c = *++argv;
+	    else
+		error("missing `,' near `%c%s'", c, argv+1);
+	}
+}
diff --git a/share/doc/psd/13.rcs/Makefile b/share/doc/psd/13.rcs/Makefile
new file mode 100644
index 0000000000000..ed497da4d8db0
--- /dev/null
+++ b/share/doc/psd/13.rcs/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+SUBDIR=	rcs rcs_func
+
+.include <bsd.subdir.mk>
+
diff --git a/share/doc/psd/13.rcs/Makefile.inc b/share/doc/psd/13.rcs/Makefile.inc
new file mode 100644
index 0000000000000..666dbd862ff25
--- /dev/null
+++ b/share/doc/psd/13.rcs/Makefile.inc
@@ -0,0 +1,5 @@
+# $FreeBSD$
+
+VOLUME=	psd/13.rcs
+MACROS=	-ms
+SRCDIR=	${.CURDIR}/../../../../../gnu/usr.bin/rcs/doc
diff --git a/share/doc/psd/13.rcs/rcs/Makefile b/share/doc/psd/13.rcs/rcs/Makefile
new file mode 100644
index 0000000000000..6d94aed2bb445
--- /dev/null
+++ b/share/doc/psd/13.rcs/rcs/Makefile
@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+SRCS=		rcs.ms
+USE_PIC=
+USE_TBL=
+
+.include <bsd.doc.mk>
diff --git a/share/doc/psd/13.rcs/rcs_func/Makefile b/share/doc/psd/13.rcs/rcs_func/Makefile
new file mode 100644
index 0000000000000..09e5a9b226c2b
--- /dev/null
+++ b/share/doc/psd/13.rcs/rcs_func/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+DOC=	rcs_func
+SRCS=	rcs_func.ms
+
+.include <bsd.doc.mk>
diff --git a/share/doc/psd/Makefile b/share/doc/psd/Makefile
index 0222c64ea68bb..243ba9992e217 100644
--- a/share/doc/psd/Makefile
+++ b/share/doc/psd/Makefile
@@ -20,6 +20,7 @@ SUBDIR=	title \
 	05.sysman \
 	06.Clang \
 	12.make \
+	13.rcs \
 	15.yacc \
 	16.lex \
 	17.m4 \
diff --git a/share/man/man5/src.conf.5 b/share/man/man5/src.conf.5
index a176bb75b6486..aad4004f5a624 100644
--- a/share/man/man5/src.conf.5
+++ b/share/man/man5/src.conf.5
@@ -909,6 +909,11 @@ This includes
 .Xr rlogin 1 ,
 .Xr rsh 1 ,
 etc.
+.It Va WITHOUT_RCS
+.\" from FreeBSD: head/tools/build/options/WITHOUT_RCS 156932 2006-03-21 07:50:50Z ru
+Set to not build
+.Xr rcs 1
+and related utilities.
 .It Va WITHOUT_RESCUE
 .\" from FreeBSD: head/tools/build/options/WITHOUT_RESCUE 156932 2006-03-21 07:50:50Z ru
 Set to not build
diff --git a/share/mk/bsd.own.mk b/share/mk/bsd.own.mk
index 5642c6edad7e0..a1b6c4412c8eb 100644
--- a/share/mk/bsd.own.mk
+++ b/share/mk/bsd.own.mk
@@ -334,6 +334,7 @@ __DEFAULT_YES_OPTIONS = \
     PROFILE \
     QUOTAS \
     RCMDS \
+    RCS \
     RESCUE \
     ROUTED \
     SENDMAIL \
diff --git a/tools/build/mk/OptionalObsoleteFiles.inc b/tools/build/mk/OptionalObsoleteFiles.inc
index 1c9fce0e8139d..dada14d115b69 100644
--- a/tools/build/mk/OptionalObsoleteFiles.inc
+++ b/tools/build/mk/OptionalObsoleteFiles.inc
@@ -3859,6 +3859,31 @@ OLD_FILES+=usr/share/man/man8/rshd.8.gz
 OLD_FILES+=usr/share/man/man8/rwhod.8.gz
 .endif
 
+.if ${MK_RCS} == no
+OLD_FILES+=usr/bin/ci
+OLD_FILES+=usr/bin/co
+OLD_FILES+=usr/bin/ident
+OLD_FILES+=usr/bin/merge
+OLD_FILES+=usr/bin/rcs
+OLD_FILES+=usr/bin/rcsclean
+OLD_FILES+=usr/bin/rcsdiff
+OLD_FILES+=usr/bin/rcsfreeze
+OLD_FILES+=usr/bin/rcsmerge
+OLD_FILES+=usr/bin/rlog
+OLD_FILES+=usr/share/man/man1/ci.1.gz
+OLD_FILES+=usr/share/man/man1/co.1.gz
+OLD_FILES+=usr/share/man/man1/ident.1.gz
+OLD_FILES+=usr/share/man/man1/merge.1.gz
+OLD_FILES+=usr/share/man/man1/rcs.1.gz
+OLD_FILES+=usr/share/man/man1/rcsclean.1.gz
+OLD_FILES+=usr/share/man/man1/rcsdiff.1.gz
+OLD_FILES+=usr/share/man/man1/rcsfreeze.1.gz
+OLD_FILES+=usr/share/man/man1/rcsintro.1.gz
+OLD_FILES+=usr/share/man/man1/rcsmerge.1.gz
+OLD_FILES+=usr/share/man/man1/rlog.1.gz
+OLD_FILES+=usr/share/man/man5/rcsfile.5.gz
+.endif
+
 #.if ${MK_RESCUE} == no
 # to be filled in or replaced with a special target
 #.endif
diff --git a/tools/build/options/WITHOUT_RCS b/tools/build/options/WITHOUT_RCS
new file mode 100644
index 0000000000000..2a4ddecab4409
--- /dev/null
+++ b/tools/build/options/WITHOUT_RCS
@@ -0,0 +1,4 @@
+.\" $FreeBSD$
+Set to not build
+.Xr rcs 1
+and related utilities.