Document the mntopts(3) functions.

The mntopts(3) functions support operations associated with a mount
point. The main purpose of this commit is to document the mntopts(3)
functions that now appear in 18 utilities in the base system. See
mntopts(3) for the documentation details.

The getmntopts() function appeared in 4.4BSD. The build_iovec(),
build_iovec_argf(), free_iovec(), checkpath(), and rmslashes()
functions were added with nmount(8) in FreeBSD 5.0. The getmntpoint()
and chkdoreload() functions are being added in this commit.

These functions should be in a library but for historic reasons are
in a file in the sources for the mount(8) program. Thus, to access
them the following lines need to be added to the Makefile of the
program wanting to use them:

SRCS+= getmntopts.c
MOUNT= ${SRCTOP}/sbin/mount
CFLAGS+= -I${MOUNT}
.PATH: ${MOUNT}

Once these changes have been MFC'ed to 13 they may be made into
a library.

Reviewed by:  kib, gbe
MFC after:    2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D37907

1 files changed, 4 insertions, 92 deletions

diff --git a/sbin/fsck_ffs/main.c b/sbin/fsck_ffs/main.c
index 7e4dcc3e1e32..14b5c1076d5e 100644
--- a/sbin/fsck_ffs/main.c
+++ b/sbin/fsck_ffs/main.c
@@ -76,8 +76,6 @@ static void usage(void) __dead2;
 static intmax_t argtoimax(int flag, const char *req, const char *str, int base);
 static int checkfilesys(char *filesys);
 static int setup_bkgrdchk(struct statfs *mntp, int sbrdfailed, char **filesys);
-static int chkdoreload(struct statfs *mntp);
-static struct statfs *getmntpt(const char *);
 
 int
 main(int argc, char *argv[])
@@ -258,7 +256,7 @@ checkfilesys(char *filesys)
 	 * if it is listed among the mounted file systems. Failing that
 	 * check to see if it is listed in /etc/fstab.
 	 */
-	mntp = getmntpt(filesys);
+	mntp = getmntpoint(filesys);
 	if (mntp != NULL)
 		filesys = mntp->f_mntfromname;
 	else
@@ -311,7 +309,7 @@ checkfilesys(char *filesys)
 			    (FS_UNCLEAN | FS_NEEDSFSCK)) == 0) {
 				bufinit();
 				gjournal_check(filesys);
-				if (chkdoreload(mntp) == 0)
+				if (chkdoreload(mntp, pwarn) == 0)
 					exit(0);
 				exit(4);
 			} else {
@@ -357,7 +355,7 @@ checkfilesys(char *filesys)
 			sujrecovery = 1;
 			if (suj_check(filesys) == 0) {
 				printf("\n***** FILE SYSTEM MARKED CLEAN *****\n");
-				if (chkdoreload(mntp) == 0)
+				if (chkdoreload(mntp, pwarn) == 0)
 					exit(0);
 				exit(4);
 			}
@@ -561,7 +559,7 @@ checkfilesys(char *filesys)
 			return (ERESTART);
 		printf("\n***** PLEASE RERUN FSCK *****\n");
 	}
-	if (chkdoreload(mntp) != 0) {
+	if (chkdoreload(mntp, pwarn) != 0) {
 		if (!fsmodified)
 			return (0);
 		if (!preen)
@@ -715,92 +713,6 @@ setup_bkgrdchk(struct statfs *mntp, int sbreadfailed, char **filesys)
 	return (1);
 }
 
-static int
-chkdoreload(struct statfs *mntp)
-{
-	struct iovec *iov;
-	int iovlen;
-	char errmsg[255];
-
-	if (mntp == NULL)
-		return (0);
-
-	iov = NULL;
-	iovlen = 0;
-	errmsg[0] = '\0';
-	/*
-	 * We modified a mounted file system.  Do a mount update on
-	 * it unless it is read-write, so we can continue using it
-	 * as safely as possible.
-	 */
-	if (mntp->f_flags & MNT_RDONLY) {
-		build_iovec(&iov, &iovlen, "fstype", "ffs", 4);
-		build_iovec(&iov, &iovlen, "from", mntp->f_mntfromname,
-		    (size_t)-1);
-		build_iovec(&iov, &iovlen, "fspath", mntp->f_mntonname,
-		    (size_t)-1);
-		build_iovec(&iov, &iovlen, "errmsg", errmsg,
-		    sizeof(errmsg));
-		build_iovec(&iov, &iovlen, "update", NULL, 0);
-		build_iovec(&iov, &iovlen, "reload", NULL, 0);
-		/*
-		 * XX: We need the following line until we clean up
-		 * nmount parsing of root mounts and NFS root mounts.
-		 */
-		build_iovec(&iov, &iovlen, "ro", NULL, 0);
-		if (nmount(iov, iovlen, mntp->f_flags) == 0) {
-			return (0);
-		}
-		pwarn("mount reload of '%s' failed: %s %s\n\n",
-		    mntp->f_mntonname, strerror(errno), errmsg);
-		return (1);
-	}
-	return (0);
-}
-
-/*
- * Get the mount point information for name.
- */
-static struct statfs *
-getmntpt(const char *name)
-{
-	struct stat devstat, mntdevstat;
-	char device[sizeof(_PATH_DEV) - 1 + MNAMELEN];
-	char *ddevname;
-	struct statfs *mntbuf, *statfsp;
-	int i, mntsize, isdev;
-
-	if (stat(name, &devstat) != 0)
-		return (NULL);
-	if (S_ISCHR(devstat.st_mode) || S_ISBLK(devstat.st_mode))
-		isdev = 1;
-	else
-		isdev = 0;
-	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
-	for (i = 0; i < mntsize; i++) {
-		statfsp = &mntbuf[i];
-		ddevname = statfsp->f_mntfromname;
-		if (*ddevname != '/') {
-			if (strlen(_PATH_DEV) + strlen(ddevname) + 1 >
-			    sizeof(statfsp->f_mntfromname))
-				continue;
-			strcpy(device, _PATH_DEV);
-			strcat(device, ddevname);
-			strcpy(statfsp->f_mntfromname, device);
-		}
-		if (isdev == 0) {
-			if (strcmp(name, statfsp->f_mntonname))
-				continue;
-			return (statfsp);
-		}
-		if (stat(ddevname, &mntdevstat) == 0 &&
-		    mntdevstat.st_rdev == devstat.st_rdev)
-			return (statfsp);
-	}
-	statfsp = NULL;
-	return (statfsp);
-}
-
 static void
 usage(void)
 {