src-test2/sys/boot/forth/support.4th, branch release/8.2.0_cvs

Copy releng/8.2 to release/8.2.0 for 8.2-RELEASE.

2011-02-16T16:18:46Z

Approved by: re (implicit) This commit was manufactured to restore the state of the 8.2-RELEASE image.

comment out some debugging messages that slipped in by mistake.

2009-01-13T12:28:14Z

MFC after: 3 days

This patch introduces a number of simplifications to the Forth

2009-01-05T20:09:54Z

functions used in the bootloader. The goal is to make the code more readable and smaller (especially because we have size issues in the loader's environment). High level description of the changes: + define some string manipulation functions to improve readability; + create functions to manipulate module descriptors, removing some duplicated code; + rename the error codes to ESOMETHING; + consistently use set_environment_variable (which evaluates $variables) when interpreting variable=value assignments; I have tested the code, but there might be code paths that I have not traversed so please let me know of any issues. Details of this change: --- loader.4th --- + add some module operators, to remove duplicated code while parsing module-related commands: set-module-flag enable-module disable-module toggle-module show-module --- pnp.4th --- + move here the definition related to the pnp devices list, e.g. STAILQ_* , pnpident, pnpinfo --- support.4th --- + rename error codes to capital e.g. ENOMEM EFREE ... and do obvious changes related to the renaming; + remove unused structures (those relevant to pnp are moved to pnp.4th) + various string functions - strlen removed (it is an internal function) - strchr, defined as the C function - strtype -- type a string to output - strref -- assign a reference to the string on the stack - unquote -- remove quotes from a string + remove reset_line_buffer + move up the 'set_environment_variable' function (which now uses the interpreter, so $variables are evaluated). Use the function in various places + add a 'test_file function' for debugging purposes MFC after: 4 weeks

PROBLEM: putting in a loader config file a line of the form

2008-12-07T19:42:20Z

loader_conf_files="foo bar baz" should cause loading the files listed, and then resume with the remaining config files (from previous values of the variable). Unfortunately, sometimes the line was ignored -- actually even modifying the line in /boot/default/loader.conf sometimes doesn't work. ANALYSIS: After much investigation, turned out to be a bug in the logic. The existing code detected a new assignment by looking at the address of the the variable containing the string. This only worked by pure chance, i.e. if the new string is longer than the previous value then the memory allocator may return a different address to store the string hence triggering the detection. SOLUTION: This commit contains a minimal change to fix the problem, without altering too much the existing structure of the code. However, as a step towards improving the quality and reliability of this code, I have introduced a handful of one-line functions (strget, strset, strfree, string= ) that could be used in dozens of places in the existing code. HOWEVER: There is a much bigger problem here. Even though I am no Forth expert (as most fellow src committers) I can tell that much of the forth code (in support.4th at least) is in severe need of a review/refactoring: + pieces of code are replicated multiple times instead of writing functions (see e.g. set_module_*); + a lot of stale code (e.g. "structure" definitions for preloaded_files, kernel_module, pnp stuff) which is not used or at least belongs elsewhere. The code bload is extremely bad as the loader runs with very small memory constraints, and we already hit the limit once (see http://svn.freebsd.org/viewvc/base?view=revision&revision=185132 Reducing the footprint of the forth files is critical. + two different styles of coding, one using pure stack functions (maybe beautiful but surely highly unreadable), one using high level mechanisms to give names to arguments and local variables (which leads to readable code). Note that this code is used by default by all FreeBSD installations, so the fragility and the code bloat are extremely damaging. I will try to work fixing the three items above, but if others have time, please have a look at these issues. MFC after: 4 weeks

Allow negative values to be specified in the loader.

2007-12-19T17:06:32Z

Replace a rarely used "depuration" with "debugging".

2006-10-13T20:48:17Z

PR: docs/85127 Submitted by: Gary W. Swearingen (partially) MFC after: 3 days

Add support for reading an additional loader configuration file. By default,

2002-05-24T02:28:58Z

this is called /boot/nextboot.conf. This file is required to have it's first line be nextboot_enable="YES" for it to be read. Also, this file is rewritten by the loader to nextboot_enable="NO" after it is read. This makes it so the file is read exactly once. Finally, the nextboot.conf is removed shortly after the filesystems are mounted r/w. Caution should be taken as you can shoot yourself in the foot. This is only the loader piece. There will be a tool called nextboot(8) that will manage the nextboot.conf file for you. It is coming shortly. Reviewed by: dcs Approved by: jake (mentor)

- Add 'fwrite' and 'fseek' words for writing to and seeking on files.

2001-12-11T00:49:34Z

- Change the 'fopen' keyword to accept a mode parameter. Note that this will break existing 4th scripts that use fopen. Thus, the loader version has been bumped and loader.4th has been changed to check for a sufficient version on i386 and alpha. Be sure that you either do a full world build or install or full build and install of sys/boot after this since loader.old won't work with the new 4th files and vice versa. PR: kern/32389 Submitted by: Jonathan Mini Sponsored by: ClickArray, Inc.

Get rid of garbage left on the stack.

2000-09-25T11:36:55Z

Use _ instead or - where proper, according to the style I have been

2000-09-16T21:04:49Z

using. Overload "?" so it will also show loader.4th commands.