void update_mtab(const char *dir, struct mntent *instead)
{
struct mntent *mnt;
struct mntent *next;
struct mntent remnt;
int added = 0;
mntFILE *mfp, *mftmp;
if (mtab_does_not_exist() || mtab_is_a_symlink())
return;
lock_mtab();
mfp = my_setmntent(MOUNTED, "r");
if (mfp == NULL || mfp->mntent_fp == NULL) {
error("cannot open %s (%s) - mtab not updated", MOUNTED, strerror(errno));
goto leave;
}
mftmp = my_setmntent(MOUNTED_TEMP, "w");
if (mftmp == NULL || mftmp->mntent_fp == NULL) {
error("can't open %s (%s) - mtab not updated", MOUNTED_TEMP, strerror(errno));
goto leave;
}
while ((mnt = my_getmntent(mfp))) {
if (streq(mnt->mnt_dir, dir)) {
added++;
if (instead) { /* a remount */
remnt = *instead;
next = &remnt;
remnt.mnt_fsname = mnt->mnt_fsname;
remnt.mnt_type = mnt->mnt_type;
if (instead->mnt_fsname && !streq(mnt->mnt_fsname, instead->mnt_fsname))
printf("mount: warning: cannot change " "mounted device with a remount\n");
else if (instead->mnt_type && !streq(instead->mnt_type, "unknown")
&& !streq(mnt->mnt_type, instead->mnt_type))
printf("mount: warning: cannot change " "filesystem type with a remount\n");
} else
next = NULL;
} else
next = mnt;
if (next && my_addmntent(mftmp, next) == 1)
die(EX_FILEIO, "error writing %s: %s", MOUNTED_TEMP, strerror(errno));
}
if (instead && !added && my_addmntent(mftmp, instead) == 1)
die(EX_FILEIO, "error writing %s: %s", MOUNTED_TEMP, strerror(errno));
my_endmntent(mfp);
if (fchmod(fileno(mftmp->mntent_fp), S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH) < 0)
fprintf(stderr, "error changing mode of %s: %s\n", MOUNTED_TEMP, strerror(errno));
my_endmntent(mftmp);
if (rename(MOUNTED_TEMP, MOUNTED) < 0)
fprintf(stderr, "can't rename %s to %s: %s\n", MOUNTED_TEMP, MOUNTED, strerror(errno));
leave:
unlock_mtab();
}
/*
* based on similar function in util-linux-2.12r/mount/mount.c
*/
static void
update_mtab_entry(const char *spec, const char *node, const char *type,
const char *opts, int freq, int pass, int addnew)
{
struct my_mntent mnt;
mnt.mnt_fsname = canonicalize (spec);
mnt.mnt_dir = canonicalize (node);
mnt.mnt_type = xstrdup(type);
mnt.mnt_opts = xstrdup(opts);
mnt.mnt_freq = freq;
mnt.mnt_passno = pass;
/* We get chatty now rather than after the update to mtab since the
mount succeeded, even if the write to /etc/mtab should fail. */
if (verbose)
print_one (&mnt);
if (!addnew)
update_mtab (mnt.mnt_dir, &mnt);
else {
mntFILE *mfp;
lock_mtab();
mfp = my_setmntent(MOUNTED, "a+");
if (mfp == NULL || mfp->mntent_fp == NULL) {
int errsv = errno;
error(_("%s: can't open %s, %s"),
progname, MOUNTED, strerror(errsv));
} else {
if ((my_addmntent (mfp, &mnt)) == 1) {
int errsv = errno;
error(_("%s: error writing %s, %s"),
progname, MOUNTED, strerror(errsv));
}
}
my_endmntent(mfp);
unlock_mtab();
}
my_free(mnt.mnt_fsname);
my_free(mnt.mnt_dir);
my_free(mnt.mnt_type);
my_free(mnt.mnt_opts);
}
/*
* Code based on similar function in util-linux-2.12p/mount/mount.c
*
*/
static void update_mtab_entry(char *spec, char *node, char *type, char *opts,
int flags, int freq, int pass)
{
struct my_mntent mnt;
mnt.mnt_fsname = canonicalize (spec);
mnt.mnt_dir = canonicalize (node);
mnt.mnt_type = type;
mnt.mnt_opts = opts;
mnt.mnt_freq = freq;
mnt.mnt_passno = pass;
/* We get chatty now rather than after the update to mtab since the
mount succeeded, even if the write to /etc/mtab should fail. */
if (verbose)
print_one (&mnt);
if (!nomtab && mtab_is_writable()) {
if (flags & MS_REMOUNT)
update_mtab (mnt.mnt_dir, &mnt);
else {
mntFILE *mfp;
lock_mtab();
mfp = my_setmntent(MOUNTED, "a+");
if (mfp == NULL || mfp->mntent_fp == NULL) {
com_err(progname, OCFS2_ET_IO, "%s, %s",
MOUNTED, strerror(errno));
} else {
if ((my_addmntent (mfp, &mnt)) == 1) {
com_err(progname, OCFS2_ET_IO, "%s, %s",
MOUNTED, strerror(errno));
}
}
my_endmntent(mfp);
unlock_mtab();
}
}
my_free(mnt.mnt_fsname);
my_free(mnt.mnt_dir);
}
void
update_mtab (const char *dir, struct my_mntent *instead) {
mntFILE *mfp, *mftmp;
const char *fnam = MOUNTED;
struct mntentchn mtabhead; /* dummy */
struct mntentchn *mc, *mc0, *absent = NULL;
if (mtab_does_not_exist() || mtab_is_a_symlink())
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 */
for (mc = mc0->prev; mc && mc != mc0; mc = mc->prev)
if (streq(mc->m.mnt_dir, dir))
break;
if (mc && mc != mc0) {
if (instead == NULL) {
/* An umount - remove entry */
if (mc && mc != mc0) {
mc->prev->nxt = mc->nxt;
mc->nxt->prev = mc->prev;
free(mc);
}
} else {
/* A remount */
mc->m.mnt_opts = instead->mnt_opts;
}
} else if (instead) {
/* not found, add a new entry */
absent = xmalloc(sizeof(*absent));
absent->m = *instead;
absent->nxt = mc0;
absent->prev = mc0->prev;
mc0->prev = absent;
if (mc0->nxt == NULL)
mc0->nxt = absent;
}
/* write chain to mtemp */
mftmp = my_setmntent (MOUNTED_TEMP, "w");
if (mftmp == NULL || mftmp->mntent_fp == NULL) {
int errsv = errno;
error (_("cannot open %s (%s) - mtab not updated"),
MOUNTED_TEMP, strerror (errsv));
goto leave;
}
for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
if (my_addmntent(mftmp, &(mc->m)) == 1) {
int errsv = errno;
die (EX_FILEIO, _("error writing %s: %s"),
MOUNTED_TEMP, strerror (errsv));
}
}
discard_mntentchn(mc0);
if (fchmod (fileno (mftmp->mntent_fp),
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH) < 0) {
int errsv = errno;
fprintf(stderr, _("error changing mode of %s: %s\n"),
MOUNTED_TEMP, strerror (errsv));
}
my_endmntent (mftmp);
{ /*
* 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.
*/
struct stat sbuf;
if (stat (MOUNTED, &sbuf) == 0)
if (chown (MOUNTED_TEMP, sbuf.st_uid, sbuf.st_gid) < 0) {
int errsv = errno;
fprintf(stderr, _("error changing ownership of %s: %s\n"),
MOUNTED_TEMP, strerror (errsv));
}
}
/* rename mtemp to mtab */
if (rename (MOUNTED_TEMP, MOUNTED) < 0) {
int errsv = errno;
fprintf(stderr, _("can't rename %s to %s: %s\n"),
MOUNTED_TEMP, MOUNTED, strerror(errsv));
}
leave:
unlock_mtab();
}
