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-rw-r--r--mount-deprecated/fstab.c988
1 files changed, 0 insertions, 988 deletions
diff --git a/mount-deprecated/fstab.c b/mount-deprecated/fstab.c
deleted file mode 100644
index 176a16b31..000000000
--- a/mount-deprecated/fstab.c
+++ /dev/null
@@ -1,988 +0,0 @@
-/* 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
- * - added Native Language Support
- * Sun Mar 21 1999 - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
- * - fixed strerr(errno) in gettext calls
- */
-
-#include <unistd.h>
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/stat.h>
-#include <sys/time.h>
-#include <time.h>
-#include <mntent.h>
-
-#include "mount_mntent.h"
-#include "fstab.h"
-#include "sundries.h"
-#include "fsprobe.h"
-#include "pathnames.h"
-#include "nls.h"
-#include "strutils.h"
-#include "c.h"
-
-#define streq(s, t) (strcmp ((s), (t)) == 0)
-
-/* Information about mtab. ------------------------------------*/
-static int have_mtab_info = 0;
-static int var_mtab_does_not_exist = 0;
-static int var_mtab_is_a_symlink = 0;
-
-static void
-get_mtab_info(void) {
- if (!have_mtab_info) {
- struct stat mtab_stat;
-
- var_mtab_does_not_exist = 0;
- var_mtab_is_a_symlink = 0;
-
- if (lstat(_PATH_MOUNTED, &mtab_stat))
- var_mtab_does_not_exist = 1;
- else if (S_ISLNK(mtab_stat.st_mode))
- var_mtab_is_a_symlink = 1;
- have_mtab_info = 1;
- }
-}
-
-void
-reset_mtab_info(void) {
- have_mtab_info = 0;
-}
-
-int
-mtab_does_not_exist(void) {
- get_mtab_info();
- return var_mtab_does_not_exist;
-}
-
-int
-mtab_is_a_symlink(void) {
- get_mtab_info();
- return var_mtab_is_a_symlink;
-}
-
-int
-mtab_is_writable() {
- int fd;
-
- /* Should we write to /etc/mtab upon an update?
- Probably not if it is a symlink to /proc/mounts, since that
- would create a file /proc/mounts in case the proc filesystem
- is not mounted. */
- if (mtab_is_a_symlink())
- return 0;
-
- fd = open(_PATH_MOUNTED, O_RDWR | O_CREAT, 0644);
- if (fd >= 0) {
- close(fd);
- return 1;
- } else
- return 0;
-}
-
-/* Contents of mtab and fstab ---------------------------------*/
-
-struct mntentchn mounttable, fstab;
-static int got_mtab = 0;
-static int got_fstab = 0;
-
-static void read_mounttable(void), read_fstab(void);
-
-struct mntentchn *
-mtab_head() {
- if (!got_mtab)
- read_mounttable();
- return &mounttable;
-}
-
-struct mntentchn *
-fstab_head() {
- if (!got_fstab)
- read_fstab();
- return &fstab;
-}
-
-static void
-my_free_mc(struct mntentchn *mc) {
- if (mc) {
- my_free(mc->m.mnt_fsname);
- my_free(mc->m.mnt_dir);
- my_free(mc->m.mnt_type);
- my_free(mc->m.mnt_opts);
- free(mc);
- }
-}
-
-
-static void
-discard_mntentchn(struct mntentchn *mc0) {
- struct mntentchn *mc, *mc1;
-
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc1) {
- mc1 = mc->nxt;
- my_free_mc(mc);
- }
-}
-
-static void
-read_mntentchn(mntFILE *mfp, const char *fnam, struct mntentchn *mc0) {
- struct mntentchn *mc = mc0;
- struct my_mntent *mnt;
-
- while ((mnt = my_getmntent(mfp)) != NULL) {
- if (!streq(mnt->mnt_type, MNTTYPE_IGNORE)) {
- mc->nxt = (struct mntentchn *) xmalloc(sizeof(*mc));
- mc->nxt->prev = mc;
- mc = mc->nxt;
- mc->m = *mnt;
- mc->nxt = mc0;
- }
- }
- mc0->prev = mc;
- if (ferror(mfp->mntent_fp)) {
- int errsv = errno;
- error(_("warning: error reading %s: %s"),
- fnam, strerror (errsv));
- mc0->nxt = mc0->prev = NULL;
- }
- my_endmntent(mfp);
-}
-
-/*
- * Read /etc/mtab. If that fails, try /proc/mounts.
- * This produces a linked list. The list head mounttable is a dummy.
- */
-static void
-read_mounttable() {
- mntFILE *mfp;
- const char *fnam;
- struct mntentchn *mc = &mounttable;
-
- got_mtab = 1;
- mc->nxt = mc->prev = NULL;
-
- fnam = _PATH_MOUNTED;
- mfp = my_setmntent (fnam, "r");
- if (mfp == NULL || mfp->mntent_fp == NULL) {
- int errsv = errno;
- fnam = _PATH_PROC_MOUNTS;
- mfp = my_setmntent (fnam, "r");
- if (mfp == NULL || mfp->mntent_fp == NULL) {
- error(_("warning: can't open %s: %s"),
- _PATH_MOUNTED, strerror (errsv));
- return;
- }
- if (verbose)
- printf (_("mount: could not open %s - "
- "using %s instead\n"),
- _PATH_MOUNTED, _PATH_PROC_MOUNTS);
- }
- read_mntentchn(mfp, fnam, mc);
-}
-
-static void
-read_fstab() {
- mntFILE *mfp = NULL;
- const char *fnam;
- struct mntentchn *mc = &fstab;
-
- got_fstab = 1;
- mc->nxt = mc->prev = NULL;
-
- fnam = _PATH_MNTTAB;
- mfp = my_setmntent (fnam, "r");
- if (mfp == NULL || mfp->mntent_fp == NULL) {
- int errsv = errno;
- error(_("warning: can't open %s: %s"),
- _PATH_MNTTAB, strerror (errsv));
- return;
- }
- read_mntentchn(mfp, fnam, mc);
-}
-
-
-/* Given the name NAME, try to find it in mtab. */
-struct mntentchn *
-getmntfile (const char *name) {
- struct mntentchn *mc, *mc0;
-
- mc0 = mtab_head();
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if (streq(mc->m.mnt_dir, name) ||
- streq(mc->m.mnt_fsname, name))
- return mc;
- return NULL;
-}
-
-/*
- * Given the name NAME, and the place MCPREV we found it last time,
- * try to find it in mtab.
- */
-struct mntentchn *
-getmntfilebackward (const char *name, struct mntentchn *mcprev) {
- struct mntentchn *mc, *mc0;
-
- mc0 = mtab_head();
- if (!mcprev)
- mcprev = mc0;
-
- for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
- if (streq(mc->m.mnt_dir, name))
- return mc;
-
- for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
- if (streq(mc->m.mnt_fsname, name))
- return mc;
-
- return NULL;
-}
-
-/*
- * Given the directory name NAME, and the place MCPREV we found it last time,
- * try to find more occurrences.
- */
-struct mntentchn *
-getmntdirbackward (const char *name, struct mntentchn *mcprev) {
- struct mntentchn *mc, *mc0;
-
- mc0 = mtab_head();
- if (!mcprev)
- mcprev = mc0;
- for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev)
- if (streq(mc->m.mnt_dir, name))
- return mc;
- return NULL;
-}
-
-/*
- * Given the device name NAME, and the place MCPREV we found it last time,
- * try to find more occurrences.
- */
-struct mntentchn *
-getmntdevbackward (const char *name, struct mntentchn *mcprev) {
- struct mntentchn *mc, *mc0;
-
- mc0 = mtab_head();
- if (!mcprev)
- mcprev = mc0;
-
- /* canonical names in mtab */
- for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev) {
- if (streq(mc->m.mnt_fsname, name))
- return mc;
- }
-
- /* non-canonical names in mtab (this is BAD THING!) */
- for (mc = mcprev->prev; mc && mc != mc0; mc = mc->prev) {
- char *cn = canonicalize(mc->m.mnt_fsname);
- int res = cn ? streq(cn, name) : 0;
-
- free(cn);
- if (res)
- return mc;
- }
-
- return NULL;
-}
-
-/*
- * Given the name NAME, check that it occurs precisely once as dir or dev.
- */
-int
-is_mounted_once(const char *name) {
- struct mntentchn *mc, *mc0;
- int ct = 0;
-
- mc0 = mtab_head();
- for (mc = mc0->prev; mc && mc != mc0; mc = mc->prev)
- if (streq(mc->m.mnt_dir, name) ||
- streq(mc->m.mnt_fsname, name))
- ct++;
- return (ct == 1);
-}
-
-/* Given the name FILE, try to find the option "loop=FILE" in mtab. */
-struct mntentchn *
-getmntoptfile (const char *file) {
- struct mntentchn *mc, *mc0;
- const char *opts, *s;
- int l;
-
- if (!file)
- return NULL;
-
- l = strlen(file);
-
- mc0 = mtab_head();
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if ((opts = mc->m.mnt_opts) != NULL
- && (s = strstr(opts, "loop="))
- && !strncmp(s+5, file, l)
- && (s == opts || s[-1] == ',')
- && (s[l+5] == 0 || s[l+5] == ','))
- return mc;
- return NULL;
-}
-
-/* compares "quoted" or 'quoted' with unquoted */
-static int
-streq_quoted(const char *quoted, const char *unquoted)
-{
- if (*quoted == '"' || *quoted == '\'')
- return !strncmp(quoted + 1, unquoted, strlen(quoted) - 2);
-
- return streq(quoted, unquoted);
-}
-
-static int
-has_label(const char *device, const char *label) {
- const char *devlabel;
- int ret;
-
- devlabel = fsprobe_get_label_by_devname(device);
- if (!devlabel)
- return 0;
-
- ret = streq_quoted(label, devlabel);
- my_free(devlabel);
- return ret;
-}
-
-static int
-has_uuid(const char *device, const char *uuid){
- const char *devuuid;
- int ret;
-
- devuuid = fsprobe_get_uuid_by_devname(device);
- if (!devuuid)
- return 0;
-
- ret = streq_quoted(uuid, devuuid);
- my_free(devuuid);
- return ret;
-}
-
-/* Find the entry (DEV,DIR) in fstab -- spec and dir must be canonicalized! */
-struct mntentchn *
-getfs_by_devdir (const char *dev, const char *dir) {
- struct mntentchn *mc, *mc0;
-
- mc0 = fstab_head();
-
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
- int ok = 1;
-
- /* dir */
- if (!streq(mc->m.mnt_dir, dir)) {
- char *dr = canonicalize(mc->m.mnt_dir);
- ok = streq(dr, dir);
- my_free(dr);
- }
-
- /* spec */
- if (ok && !streq(mc->m.mnt_fsname, dev)) {
- const char *fs = mc->m.mnt_fsname;
-
- if (strncmp (fs, "LABEL=", 6) == 0) {
- ok = has_label(dev, fs + 6);
- } else if (strncmp (fs, "UUID=", 5) == 0) {
- ok = has_uuid(dev, fs + 5);
- } else {
- fs = canonicalize_spec(mc->m.mnt_fsname);
- ok = streq_except_trailing_slash(fs, dev);
- my_free(fs);
- }
- }
- if (ok)
- return mc;
- }
-
- return NULL;
-}
-
-/* Find the dir DIR in fstab. */
-struct mntentchn *
-getfs_by_dir (const char *dir) {
- struct mntentchn *mc, *mc0;
- char *cdir;
-
- mc0 = fstab_head();
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if (streq(mc->m.mnt_dir, dir))
- return mc;
-
- cdir = canonicalize(dir);
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
- int ok = streq(mc->m.mnt_dir, cdir);
- if (!ok) {
- char *dr = canonicalize(mc->m.mnt_dir);
- ok = dr ? streq(dr, cdir) : 0;
- free(dr);
- }
- if (ok) {
- free(cdir);
- return mc;
- }
- }
- free(cdir);
- return NULL;
-}
-
-/* Find the device SPEC in fstab. */
-struct mntentchn *
-getfs_by_spec (const char *spec) {
- char *name = NULL, *value = NULL, *cspec;
- struct mntentchn *mc = NULL;
-
- if (!spec)
- return NULL;
-
- if (fsprobe_parse_spec(spec, &name, &value) != 0)
- return NULL; /* parse error */
-
- if (name) {
- if (!strcmp(name,"LABEL"))
- mc = getfs_by_label (value);
- else if (!strcmp(name,"UUID"))
- mc = getfs_by_uuid (value);
-
- free(name);
- free(value);
- return mc;
- }
-
- cspec = canonicalize_spec(spec);
- mc = getfs_by_devname(cspec);
- free(cspec);
-
- if (!mc)
- /* noncanonical name like /dev/cdrom */
- mc = getfs_by_devname(spec);
-
- return mc;
-}
-
-/* Find the device in fstab. */
-struct mntentchn *
-getfs_by_devname (const char *devname) {
- struct mntentchn *mc, *mc0;
-
- mc0 = fstab_head();
-
- /* canonical devname in fstab */
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if (streq(mc->m.mnt_fsname, devname))
- return mc;
-
- /* noncanonical devname in fstab */
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
- char *fs;
-
- if (strncmp(mc->m.mnt_fsname, "LABEL=", 6) == 0 ||
- strncmp(mc->m.mnt_fsname, "UUID=", 5) == 0)
- continue;
-
- fs = canonicalize_spec(mc->m.mnt_fsname);
- if (streq(fs, devname)) {
- free(fs);
- return mc;
- }
- free(fs);
- }
-
- return NULL;
-}
-
-
-/* Find the uuid UUID in fstab. */
-struct mntentchn *
-getfs_by_uuid (const char *uuid) {
- struct mntentchn *mc, *mc0;
-
- mc0 = fstab_head();
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if (strncmp (mc->m.mnt_fsname, "UUID=", 5) == 0
- && streq_quoted(mc->m.mnt_fsname + 5, uuid))
- return mc;
- return NULL;
-}
-
-/* Find the label LABEL in fstab. */
-struct mntentchn *
-getfs_by_label (const char *label) {
- struct mntentchn *mc, *mc0;
-
- mc0 = fstab_head();
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
- if (strncmp (mc->m.mnt_fsname, "LABEL=", 6) == 0
- && streq_quoted(mc->m.mnt_fsname + 6, label))
- return mc;
- return NULL;
-}
-
-/* Updating mtab ----------------------------------------------*/
-
-/* Flag for already existing lock file. */
-static int we_created_lockfile = 0;
-static int lockfile_fd = -1;
-
-/* Flag to indicate that signals have been set up. */
-static int signals_have_been_setup = 0;
-
-/* Ensure that the lock is released if we are interrupted. */
-#ifndef HAVE_STRSIGNAL_DECL
-extern char *strsignal(int sig); /* not always in <string.h> */
-#endif
-
-static void
-handler (int sig) {
- die(EX_USER, "%s", strsignal(sig));
-}
-
-static void
-setlkw_timeout (int sig __attribute__ ((__unused__))) {
- /* nothing, fcntl will fail anyway */
-}
-
-/* Remove lock file. */
-void
-unlock_mtab (void) {
- if (we_created_lockfile) {
- close(lockfile_fd);
- lockfile_fd = -1;
- unlink (_PATH_MOUNTED_LOCK);
- we_created_lockfile = 0;
- }
-}
-
-/* Create the lock file.
- The lock file will be removed if we catch a signal or when we exit. */
-/* The old code here used flock on a lock file /etc/mtab~ and deleted
- this lock file afterwards. However, as rgooch remarks, that has a
- race: a second mount may be waiting on the lock and proceed as
- soon as the lock file is deleted by the first mount, and immediately
- afterwards a third mount comes, creates a new /etc/mtab~, applies
- flock to that, and also proceeds, so that the second and third mount
- now both are scribbling in /etc/mtab.
- The new code uses a link() instead of a creat(), where we proceed
- only if it was us that created the lock, and hence we always have
- to delete the lock afterwards. Now the use of flock() is in principle
- superfluous, but avoids an arbitrary sleep(). */
-
-/* Where does the link point to? Obvious choices are mtab and mtab~~.
- HJLu points out that the latter leads to races. Right now we use
- mtab~.<pid> instead. Use 20 as upper bound for the length of %d. */
-#define MOUNTLOCK_LINKTARGET _PATH_MOUNTED_LOCK "%d"
-#define MOUNTLOCK_LINKTARGET_LTH (sizeof(_PATH_MOUNTED_LOCK)+20)
-
-/*
- * The original mount locking code has used sleep(1) between attempts and
- * maximal number of attemps has been 5.
- *
- * There was very small number of attempts and extremely long waiting (1s)
- * that is useless on machines with large number of concurret mount processes.
- *
- * Now we wait few thousand microseconds between attempts and we have global
- * time limit (30s) rather than limit for number of attempts. The advantage
- * is that this method also counts time which we spend in fcntl(F_SETLKW) and
- * number of attempts is not so much restricted.
- *
- * -- kzak@redhat.com [2007-Mar-2007]
- */
-
-/* maximum seconds between first and last attempt */
-#define MOUNTLOCK_MAXTIME 30
-
-/* sleep time (in microseconds, max=999999) between attempts */
-#define MOUNTLOCK_WAITTIME 5000
-
-void
-lock_mtab (void) {
- int i;
- struct timespec waittime;
- struct timeval maxtime;
- char linktargetfile[MOUNTLOCK_LINKTARGET_LTH];
-
- if (!signals_have_been_setup) {
- int sig = 0;
- struct sigaction sa;
-
- sa.sa_handler = handler;
- sa.sa_flags = 0;
- sigfillset (&sa.sa_mask);
-
- while (sigismember (&sa.sa_mask, ++sig) != -1
- && sig != SIGCHLD) {
- if (sig == SIGALRM)
- sa.sa_handler = setlkw_timeout;
- else
- sa.sa_handler = handler;
- sigaction (sig, &sa, (struct sigaction *) 0);
- }
- signals_have_been_setup = 1;
- }
-
- sprintf(linktargetfile, MOUNTLOCK_LINKTARGET, getpid ());
-
- i = open (linktargetfile, O_WRONLY|O_CREAT, S_IRUSR|S_IWUSR);
- if (i < 0) {
- int errsv = errno;
- /* linktargetfile does not exist (as a file)
- and we cannot create it. Read-only filesystem?
- Too many files open in the system?
- Filesystem full? */
- die (EX_FILEIO, _("can't create lock file %s: %s "
- "(use -n flag to override)"),
- linktargetfile, strerror (errsv));
- }
- close(i);
-
- gettimeofday(&maxtime, NULL);
- maxtime.tv_sec += MOUNTLOCK_MAXTIME;
-
- waittime.tv_sec = 0;
- waittime.tv_nsec = (1000 * MOUNTLOCK_WAITTIME);
-
- /* Repeat until it was us who made the link */
- while (!we_created_lockfile) {
- struct timeval now;
- struct flock flock;
- int errsv, j;
-
- j = link(linktargetfile, _PATH_MOUNTED_LOCK);
- errsv = errno;
-
- if (j == 0)
- we_created_lockfile = 1;
-
- if (j < 0 && errsv != EEXIST) {
- (void) unlink(linktargetfile);
- die (EX_FILEIO, _("can't link lock file %s: %s "
- "(use -n flag to override)"),
- _PATH_MOUNTED_LOCK, strerror (errsv));
- }
-
- lockfile_fd = open (_PATH_MOUNTED_LOCK, O_WRONLY);
-
- if (lockfile_fd < 0) {
- /* Strange... Maybe the file was just deleted? */
- int errsv = errno;
- gettimeofday(&now, NULL);
- if (errno == ENOENT && now.tv_sec < maxtime.tv_sec) {
- we_created_lockfile = 0;
- continue;
- }
- (void) unlink(linktargetfile);
- die (EX_FILEIO, _("can't open lock file %s: %s "
- "(use -n flag to override)"),
- _PATH_MOUNTED_LOCK, strerror (errsv));
- }
-
- flock.l_type = F_WRLCK;
- flock.l_whence = SEEK_SET;
- flock.l_start = 0;
- flock.l_len = 0;
-
- if (j == 0) {
- /* We made the link. Now claim the lock. */
- if (fcntl (lockfile_fd, F_SETLK, &flock) == -1) {
- if (verbose) {
- int errsv = errno;
- printf(_("Can't lock lock file %s: %s\n"),
- _PATH_MOUNTED_LOCK, strerror (errsv));
- }
- /* proceed, since it was us who created the lockfile anyway */
- }
- (void) unlink(linktargetfile);
- } else {
- /* Someone else made the link. Wait. */
- gettimeofday(&now, NULL);
- if (now.tv_sec < maxtime.tv_sec) {
- alarm(maxtime.tv_sec - now.tv_sec);
- if (fcntl (lockfile_fd, F_SETLKW, &flock) == -1) {
- int errsv = errno;
- (void) unlink(linktargetfile);
- die (EX_FILEIO, _("can't lock lock file %s: %s"),
- _PATH_MOUNTED_LOCK, (errno == EINTR) ?
- _("timed out") : strerror (errsv));
- }
- alarm(0);
-
- nanosleep(&waittime, NULL);
- } else {
- (void) unlink(linktargetfile);
- die (EX_FILEIO, _("Cannot create link %s\n"
- "Perhaps there is a stale lock file?\n"),
- _PATH_MOUNTED_LOCK);
- }
- close(lockfile_fd);
- }
- }
-}
-
-/* returns whole option with name @optname from @src list */
-char *
-get_option(const char *optname, const char *src, size_t *len)
-{
- char *opt, *end;
- size_t sz;
-
- if (!src)
- return NULL;
-
- opt = strstr(src, optname);
- if (!opt)
- return NULL;
-
- end = strchr(opt, ',');
- sz = end && end > opt ? (size_t) (end - opt) : strlen(opt);
-
- if (len)
- *len = sz;
-
- if ((opt == src || *(opt - 1) == ',') &&
- (*(opt + sz) == '\0' || *(opt + sz) == ','))
- return opt;
-
- return NULL;
-}
-
- /* If @list contains "user=peter" and @s is "user=", return "peter" */
-char *
-get_option_value(const char *list, const char *s)
-{
- const char *t;
- size_t n = strlen(s);
-
- while (list && *list) {
- if (strncmp(list, s, n) == 0) {
- s = t = list + n;
- while (*s && *s != ',')
- s++;
- return xstrndup(t, s-t);
- }
- while (*list && *list++ != ',') ;
- }
- return NULL;
-}
-
-static int
-cpy_option(const char *optname, char *dest, const char *src)
-{
- char *opt;
- size_t sz;
-
- opt = get_option(optname, src, &sz);
- if (!opt)
- /* the option doesn't exist */
- return 0;
-
- if (get_option(optname, dest, NULL))
- /* the options is already in dest */
- return 0;
-
- if (*dest) {
- dest = dest + strlen(dest);
- *dest++ = ','; /* separator */
- }
- memcpy(dest, opt, sz); /* copy option */
- *(dest + sz) = '\0'; /* terminator */
-
- return 1;
-}
-
-/* Generates (and allocates) new options for remount
- *
- * We cannot blindly replace the old options, otherwise we will lost some
- * internally generated stuff (e.g loop=).
- */
-static char *
-mk_remount_opts(const char *old, const char *instead)
-{
- char *new;
- size_t sz;
-
- if (old == NULL && instead == NULL)
- return NULL;
- if (!old)
- return xstrdup(instead);
-
- /* max size of new options is:
- * old + new + '\0' + separator (for each copied option)
- */
- sz = strlen(old) + (instead ? strlen(instead) : 0) + 2;
- new = xmalloc(sz);
- if (instead && *instead)
- strncpy(new, instead, sz);
- else
- *new = '\0';
-
- cpy_option("loop=", new, old);
-
- return new;
-}
-
-/*
- * Update the mtab.
- * Used by umount with null INSTEAD: remove the last DIR entry.
- * Used by mount upon a remount: update option part,
- * and complain if a wrong device or type was given.
- * [Note that often a remount will be a rw remount of /
- * where there was no entry before, and we'll have to believe
- * the values given in INSTEAD.]
- */
-
-void
-update_mtab (const char *dir, struct my_mntent *instead) {
- mntFILE *mfp, *mftmp;
- const char *fnam = _PATH_MOUNTED;
- struct mntentchn mtabhead; /* dummy */
- struct mntentchn *mc, *mc0 = NULL, *absent = NULL;
- struct stat sbuf;
- int fd;
-
- if (mtab_does_not_exist() || !mtab_is_writable())
- return;
-
- lock_mtab();
-
- /* having locked mtab, read it again */
- mc0 = mc = &mtabhead;
- mc->nxt = mc->prev = NULL;
-
- mfp = my_setmntent(fnam, "r");
- if (mfp == NULL || mfp->mntent_fp == NULL) {
- int errsv = errno;
- error (_("cannot open %s (%s) - mtab not updated"),
- fnam, strerror (errsv));
- goto leave;
- }
-
- read_mntentchn(mfp, fnam, mc);
-
- /* find last occurrence of dir */
- if (dir) {
- for (mc = mc0->prev; mc && mc != mc0; mc = mc->prev)
- if (streq(mc->m.mnt_dir, dir))
- break;
- }
- if (dir && mc && mc != mc0) {
- if (instead == NULL) {
- /* An umount - remove entry */
- if (mc && mc != mc0) {
- mc->prev->nxt = mc->nxt;
- mc->nxt->prev = mc->prev;
- my_free_mc(mc);
- }
- } else if (!strcmp(mc->m.mnt_dir, instead->mnt_dir)) {
- /* A remount */
- char *opts = mk_remount_opts(mc->m.mnt_opts,
- instead->mnt_opts);
- my_free(mc->m.mnt_opts);
- mc->m.mnt_opts = opts;
- } else {
- /* A move */
- my_free(mc->m.mnt_dir);
- mc->m.mnt_dir = xstrdup(instead->mnt_dir);
- }
- } else if (instead) {
- /* not found, add a new entry */
- absent = xmalloc(sizeof(*absent));
- absent->m.mnt_fsname = xstrdup(instead->mnt_fsname);
- absent->m.mnt_dir = xstrdup(instead->mnt_dir);
- absent->m.mnt_type = xstrdup(instead->mnt_type);
- absent->m.mnt_opts = xstrdup(instead->mnt_opts);
- absent->m.mnt_freq = instead->mnt_freq;
- absent->m.mnt_passno = instead->mnt_passno;
- absent->nxt = mc0;
- if (mc0->prev != NULL) {
- absent->prev = mc0->prev;
- mc0->prev->nxt = absent;
- } else {
- absent->prev = mc0;
- }
- mc0->prev = absent;
- if (mc0->nxt == NULL)
- mc0->nxt = absent;
- }
-
- /* write chain to mtemp */
- mftmp = my_setmntent (_PATH_MOUNTED_TMP, "w");
- if (mftmp == NULL || mftmp->mntent_fp == NULL) {
- int errsv = errno;
- error (_("cannot open %s (%s) - mtab not updated"),
- _PATH_MOUNTED_TMP, strerror (errsv));
- goto leave;
- }
-
- for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
- if (my_addmntent(mftmp, &(mc->m)) == 1) {
- int errsv = errno;
- error(_("error writing %s: %s"),
- _PATH_MOUNTED_TMP, strerror (errsv));
- goto leave;
- }
- }
-
- discard_mntentchn(mc0);
- mc0 = NULL;
-
- /*
- * We have to be paranoid with write() to avoid incomplete
- * /etc/mtab. Users are able to control writing by RLIMIT_FSIZE.
- */
- if (fflush(mftmp->mntent_fp) != 0) {
- int errsv = errno;
- error (_("%s: cannot fflush changes: %s"),
- _PATH_MOUNTED_TMP, strerror (errsv));
- goto leave;
- }
-
- fd = fileno(mftmp->mntent_fp);
-
- /*
- * It seems that better is incomplete and broken /etc/mtab that
- * /etc/mtab that is writeable for non-root users.
- *
- * We always skip rename() when chown() and chmod() failed.
- * -- kzak, 11-Oct-2007
- */
-
- if (fchmod(fd, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH) < 0) {
- int errsv = errno;
- fprintf(stderr, _("error changing mode of %s: %s\n"),
- _PATH_MOUNTED_TMP, strerror (errsv));
- goto leave;
- }
-
- /*
- * If mount is setuid and some non-root user mounts sth,
- * then mtab.tmp might get the group of this user. Copy uid/gid
- * from the present mtab before renaming.
- */
- if (stat(_PATH_MOUNTED, &sbuf) == 0) {
- if (fchown(fd, sbuf.st_uid, sbuf.st_gid) < 0) {
- int errsv = errno;
- fprintf (stderr, _("error changing owner of %s: %s\n"),
- _PATH_MOUNTED_TMP, strerror(errsv));
- goto leave;
- }
- }
-
- my_endmntent (mftmp);
-
- /* rename mtemp to mtab */
- if (rename (_PATH_MOUNTED_TMP, _PATH_MOUNTED) < 0) {
- int errsv = errno;
- fprintf(stderr, _("can't rename %s to %s: %s\n"),
- _PATH_MOUNTED_TMP, _PATH_MOUNTED, strerror(errsv));
- }
-
- leave:
- if (mc0)
- discard_mntentchn(mc0);
- unlink(_PATH_MOUNTED_TMP);
- unlock_mtab();
-}
-
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-06-07 02:32:39 +0200