/**
* mnt_table_parse_stream:
* @tb: tab pointer
* @f: file stream
* @filename: filename used for debug and error messages
*
* Returns: 0 on success, negative number in case of error.
*/
int mnt_table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename)
{
int nlines = 0;
int rc = -1;
int flags = 0;
pid_t tid = -1;
assert(tb);
assert(f);
assert(filename);
DBG(TAB, mnt_debug_h(tb, "%s: start parsing [entries=%d, filter=%s]",
filename, mnt_table_get_nents(tb),
tb->fltrcb ? "yes" : "not"));
/* necessary for /proc/mounts only, the /proc/self/mountinfo
* parser sets the flag properly
*/
if (filename && strcmp(filename, _PATH_PROC_MOUNTS) == 0)
flags = MNT_FS_KERNEL;
while (!feof(f)) {
struct libmnt_fs *fs = mnt_new_fs();
if (!fs)
goto err;
rc = mnt_table_parse_next(tb, f, fs, filename, &nlines);
if (!rc && tb->fltrcb && tb->fltrcb(fs, tb->fltrcb_data))
rc = 1; /* filtered out by callback... */
if (!rc) {
rc = mnt_table_add_fs(tb, fs);
fs->flags |= flags;
if (rc == 0 && tb->fmt == MNT_FMT_MOUNTINFO)
rc = kernel_fs_postparse(tb, fs, &tid, filename);
}
mnt_unref_fs(fs);
if (rc) {
if (rc == 1)
continue; /* recoverable error */
if (feof(f))
break;
goto err; /* fatal error */
}
}
DBG(TAB, mnt_debug_h(tb, "%s: stop parsing (%d entries)",
filename, mnt_table_get_nents(tb)));
return 0;
err:
DBG(TAB, mnt_debug_h(tb, "%s: parse error (rc=%d)", filename, rc));
return rc;
}
/**
* mnt_table_parse_stream:
* @tb: tab pointer
* @f: file stream
* @filename: filename used for debug and error messages
*
* Returns: 0 on success, negative number in case of error.
*/
int mnt_table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename)
{
int nlines = 0;
int rc = -1;
int flags = 0;
pid_t tid = -1;
assert(tb);
assert(f);
assert(filename);
DBG(TAB, mnt_debug_h(tb, "%s: start parsing (%d entries)",
filename, mnt_table_get_nents(tb)));
/* necessary for /proc/mounts only, the /proc/self/mountinfo
* parser sets the flag properly
*/
if (filename && strcmp(filename, _PATH_PROC_MOUNTS) == 0)
flags = MNT_FS_KERNEL;
while (!feof(f)) {
struct libmnt_fs *fs = mnt_new_fs();
if (!fs)
goto err;
rc = mnt_table_parse_next(tb, f, fs, filename, &nlines);
if (!rc) {
rc = mnt_table_add_fs(tb, fs);
fs->flags |= flags;
if (tb->fmt == MNT_FMT_MOUNTINFO && filename) {
if (tid == -1)
tid = path_to_tid(filename);
fs->tid = tid;
}
}
if (rc) {
mnt_free_fs(fs);
if (rc == 1)
continue; /* recoverable error */
if (feof(f))
break;
goto err; /* fatal error */
}
}
DBG(TAB, mnt_debug_h(tb, "%s: stop parsing (%d entries)",
filename, mnt_table_get_nents(tb)));
return 0;
err:
DBG(TAB, mnt_debug_h(tb, "%s: parse error (rc=%d)", filename, rc));
return rc;
}
static int append_comment(struct libmnt_table *tb,
struct libmnt_fs *fs,
const char *comm,
int eof)
{
int rc, intro = mnt_table_get_nents(tb) == 0;
if (intro && is_terminated_by_blank(mnt_table_get_intro_comment(tb)))
intro = 0;
DBG(TAB, mnt_debug_h(tb, "appending %s comment",
intro ? "intro" :
eof ? "trailing" : "fs"));
if (intro)
rc = mnt_table_append_intro_comment(tb, comm);
else if (eof) {
rc = mnt_table_set_trailing_comment(tb,
mnt_fs_get_comment(fs));
if (!rc)
rc = mnt_table_append_trailing_comment(tb, comm);
if (!rc)
rc = mnt_fs_set_comment(fs, NULL);
} else
rc = mnt_fs_append_comment(fs, comm);
return rc;
}
/**
* mnt_table_parse_mtab:
* @tb: table
* @filename: overwrites default (/etc/mtab or $LIBMOUNT_MTAB) or NULL
*
* This function parses /etc/mtab or /proc/self/mountinfo +
* /run/mount/utabs or /proc/mounts.
*
* See also mnt_table_set_parser_errcb().
*
* Returns: 0 on success or negative number in case of error.
*/
int mnt_table_parse_mtab(struct libmnt_table *tb, const char *filename)
{
int rc;
const char *utab = NULL;
struct libmnt_table *u_tb;
assert(tb);
if (mnt_has_regular_mtab(&filename, NULL)) {
DBG(TAB, mnt_debug_h(tb, "force %s usage", filename));
rc = mnt_table_parse_file(tb, filename);
if (!rc)
return 0;
filename = NULL; /* failed */
}
/*
* useless /etc/mtab
* -- read kernel information from /proc/self/mountinfo
*/
tb->fmt = MNT_FMT_MOUNTINFO;
rc = mnt_table_parse_file(tb, _PATH_PROC_MOUNTINFO);
if (rc) {
/* hmm, old kernel? ...try /proc/mounts */
tb->fmt = MNT_FMT_MTAB;
return mnt_table_parse_file(tb, _PATH_PROC_MOUNTS);
}
if (mnt_table_get_nents(tb) == 0)
return 0; /* empty, ignore utab */
/*
* try to read the user specific information from /run/mount/utabs
*/
utab = mnt_get_utab_path();
if (!utab || is_file_empty(utab))
return 0;
u_tb = mnt_new_table();
if (!u_tb)
return -ENOMEM;
u_tb->fmt = MNT_FMT_UTAB;
mnt_table_set_parser_fltrcb(u_tb, tb->fltrcb, tb->fltrcb_data);
if (mnt_table_parse_file(u_tb, utab) == 0) {
struct libmnt_fs *u_fs;
struct libmnt_iter itr;
mnt_reset_iter(&itr, MNT_ITER_BACKWARD);
/* merge user options into mountinfo from the kernel */
while(mnt_table_next_fs(u_tb, &itr, &u_fs) == 0)
mnt_table_merge_user_fs(tb, u_fs);
}
mnt_unref_table(u_tb);
return 0;
}
/**
* mnt_context_find_umount_fs:
* @cxt: mount context
* @tgt: mountpoint, device, ...
* @pfs: returns point to filesystem
*
* Returns: 0 on success, <0 on error, 1 if target filesystem not found
*/
int mnt_context_find_umount_fs(struct libmnt_context *cxt,
const char *tgt,
struct libmnt_fs **pfs)
{
int rc;
struct libmnt_table *mtab = NULL;
struct libmnt_fs *fs;
char *loopdev = NULL;
if (pfs)
*pfs = NULL;
if (!cxt || !tgt || !pfs)
return -EINVAL;
DBG(CXT, ul_debugobj(cxt, "umount: lookup FS for '%s'", tgt));
if (!*tgt)
return 1; /* empty string is not an error */
/*
* The mount table may be huge, and on systems with utab we have to merge
* userspace mount options into /proc/self/mountinfo. This all is
* expensive. The tab filter allows to filter out entries, then
* a mount table and utab are very tiny files.
*
* *but*... the filter uses mnt_fs_streq_{target,srcpath} functions
* where LABEL, UUID or symlinks are canonicalized. It means that
* it's usable only for canonicalized stuff (e.g. kernel mountinfo).
*/
if (!mnt_context_mtab_writable(cxt) && *tgt == '/' &&
!mnt_context_is_force(cxt) && !mnt_context_is_lazy(cxt))
rc = mnt_context_get_mtab_for_target(cxt, &mtab, tgt);
else
rc = mnt_context_get_mtab(cxt, &mtab);
if (rc) {
DBG(CXT, ul_debugobj(cxt, "umount: failed to read mtab"));
return rc;
}
if (mnt_table_get_nents(mtab) == 0) {
DBG(CXT, ul_debugobj(cxt, "umount: mtab empty"));
return 1;
}
try_loopdev:
fs = mnt_table_find_target(mtab, tgt, MNT_ITER_BACKWARD);
if (!fs && mnt_context_is_swapmatch(cxt)) {
/*
* Maybe the option is source rather than target (sometimes
* people use e.g. "umount /dev/sda1")
*/
fs = mnt_table_find_source(mtab, tgt, MNT_ITER_BACKWARD);
if (fs) {
struct libmnt_fs *fs1 = mnt_table_find_target(mtab,
mnt_fs_get_target(fs),
MNT_ITER_BACKWARD);
if (!fs1) {
DBG(CXT, ul_debugobj(cxt, "mtab is broken?!?!"));
rc = -EINVAL;
goto err;
}
if (fs != fs1) {
/* Something was stacked over `file' on the
* same mount point. */
DBG(CXT, ul_debugobj(cxt,
"umount: %s: %s is mounted "
"over it on the same point",
tgt, mnt_fs_get_source(fs1)));
rc = -EINVAL;
goto err;
}
}
}
if (!fs && !loopdev && mnt_context_is_swapmatch(cxt)) {
/*
* Maybe the option is /path/file.img, try to convert to /dev/loopN
*/
struct stat st;
if (mnt_stat_mountpoint(tgt, &st) == 0 && S_ISREG(st.st_mode)) {
int count;
struct libmnt_cache *cache = mnt_context_get_cache(cxt);
const char *bf = cache ? mnt_resolve_path(tgt, cache) : tgt;
count = loopdev_count_by_backing_file(bf, &loopdev);
if (count == 1) {
DBG(CXT, ul_debugobj(cxt,
"umount: %s --> %s (retry)", tgt, loopdev));
tgt = loopdev;
goto try_loopdev;
} else if (count > 1)
DBG(CXT, ul_debugobj(cxt,
"umount: warning: %s is associated "
"with more than one loopdev", tgt));
}
}
if (pfs)
*pfs = fs;
free(loopdev);
DBG(CXT, ul_debugobj(cxt, "umount fs: %s", fs ? mnt_fs_get_target(fs) :
"<not found>"));
return fs ? 0 : 1;
err:
free(loopdev);
return rc;
}
/**
* mnt_table_parse_stream:
* @tb: tab pointer
* @f: file stream
* @filename: filename used for debug and error messages
*
* Returns: 0 on success, negative number in case of error.
*/
int mnt_table_parse_stream(struct libmnt_table *tb, FILE *f, const char *filename)
{
int rc = -1;
int flags = 0;
pid_t tid = -1;
struct libmnt_fs *fs = NULL;
struct libmnt_parser pa = { .line = 0 };
assert(tb);
assert(f);
assert(filename);
DBG(TAB, ul_debugobj(tb, "%s: start parsing [entries=%d, filter=%s]",
filename, mnt_table_get_nents(tb),
tb->fltrcb ? "yes" : "not"));
pa.filename = filename;
pa.f = f;
/* necessary for /proc/mounts only, the /proc/self/mountinfo
* parser sets the flag properly
*/
if (filename && strcmp(filename, _PATH_PROC_MOUNTS) == 0)
flags = MNT_FS_KERNEL;
while (!feof(f)) {
if (!fs) {
fs = mnt_new_fs();
if (!fs)
goto err;
}
rc = mnt_table_parse_next(&pa, tb, fs);
if (!rc && tb->fltrcb && tb->fltrcb(fs, tb->fltrcb_data))
rc = 1; /* filtered out by callback... */
if (!rc) {
rc = mnt_table_add_fs(tb, fs);
fs->flags |= flags;
if (rc == 0 && tb->fmt == MNT_FMT_MOUNTINFO) {
rc = kernel_fs_postparse(tb, fs, &tid, filename);
if (rc)
mnt_table_remove_fs(tb, fs);
}
}
if (rc) {
if (rc > 0) {
mnt_reset_fs(fs);
assert(fs->refcount == 1);
continue; /* recoverable error, reuse fs*/
}
mnt_unref_fs(fs);
if (feof(f))
break;
goto err; /* fatal error */
}
mnt_unref_fs(fs);
fs = NULL;
}
DBG(TAB, ul_debugobj(tb, "%s: stop parsing (%d entries)",
filename, mnt_table_get_nents(tb)));
parser_cleanup(&pa);
return 0;
err:
DBG(TAB, ul_debugobj(tb, "%s: parse error (rc=%d)", filename, rc));
parser_cleanup(&pa);
return rc;
}
/**
* mnt_table_parse_file:
* @tb: tab pointer
* @filename: file
*
* Parses the whole table (e.g. /etc/fstab) and appends new records to the @tab.
*
* The libmount parser ignores broken (syntax error) lines, these lines are
* reported to the caller by the errcb() function (see mnt_table_set_parser_errcb()).
*
* Returns: 0 on success, negative number in case of error.
*/
int mnt_table_parse_file(struct libmnt_table *tb, const char *filename)
{
FILE *f;
int rc;
if (!filename || !tb)
return -EINVAL;
f = fopen(filename, "r" UL_CLOEXECSTR);
if (f) {
rc = mnt_table_parse_stream(tb, f, filename);
fclose(f);
} else
rc = -errno;
DBG(TAB, ul_debugobj(tb, "parsing done [filename=%s, rc=%d]", filename, rc));
return rc;
}
/* default filename is /proc/self/mountinfo
*/
int __mnt_table_parse_mtab(struct libmnt_table *tb, const char *filename,
struct libmnt_table *u_tb)
{
int rc = 0, priv_utab = 0;
assert(tb);
if (filename)
DBG(TAB, ul_debugobj(tb, "%s reuested as mtab", filename));
#ifdef USE_LIBMOUNT_SUPPORT_MTAB
if (mnt_has_regular_mtab(&filename, NULL)) {
DBG(TAB, ul_debugobj(tb, "force mtab usage [filename=%s]", filename));
rc = mnt_table_parse_file(tb, filename);
/*
* If @filename forces us to read from /proc then also read
* utab file to merge userspace mount options.
*/
if (rc == 0 && is_mountinfo(tb))
goto read_utab;
if (!rc)
return 0;
filename = NULL; /* failed */
} else
filename = NULL; /* mtab useless */
#endif
if (!filename || strcmp(filename, _PATH_PROC_MOUNTINFO) == 0) {
filename = _PATH_PROC_MOUNTINFO;
tb->fmt = MNT_FMT_MOUNTINFO;
DBG(TAB, ul_debugobj(tb, "mtab parse: #1 read mountinfo"));
} else
tb->fmt = MNT_FMT_GUESS;
rc = mnt_table_parse_file(tb, filename);
if (rc) {
/* hmm, old kernel? ...try /proc/mounts */
tb->fmt = MNT_FMT_MTAB;
return mnt_table_parse_file(tb, _PATH_PROC_MOUNTS);
}
if (!is_mountinfo(tb))
return 0;
#ifdef USE_LIBMOUNT_SUPPORT_MTAB
read_utab:
#endif
DBG(TAB, ul_debugobj(tb, "mtab parse: #2 read utab"));
if (mnt_table_get_nents(tb) == 0)
return 0; /* empty, ignore utab */
/*
* try to read the user specific information from /run/mount/utabs
*/
if (!u_tb) {
const char *utab = mnt_get_utab_path();
if (!utab || is_file_empty(utab))
return 0;
u_tb = mnt_new_table();
if (!u_tb)
return -ENOMEM;
u_tb->fmt = MNT_FMT_UTAB;
mnt_table_set_parser_fltrcb(u_tb, tb->fltrcb, tb->fltrcb_data);
rc = mnt_table_parse_file(u_tb, utab);
priv_utab = 1;
}
DBG(TAB, ul_debugobj(tb, "mtab parse: #3 merge utab"));
if (rc == 0) {
struct libmnt_fs *u_fs;
struct libmnt_iter itr;
mnt_reset_iter(&itr, MNT_ITER_BACKWARD);
/* merge user options into mountinfo from the kernel */
while(mnt_table_next_fs(u_tb, &itr, &u_fs) == 0)
mnt_table_merge_user_fs(tb, u_fs);
}
if (priv_utab)
mnt_unref_table(u_tb);
return 0;
}
