/*
- * mountpoint(1) - see if a directory is a mountpoint
- *
- * This is libmount based reimplementation of the mountpoit(1)
- * from sysvinit project.
- *
+ * SPDX-License-Identifier: GPL-2.0-or-later
*
* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
* Written by Karel Zak <kzak@redhat.com>
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
- * This program is distributed in the hope that it would be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * mountpoint(1) - see if a directory is a mountpoint
*
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * This is libmount based reimplementation of the mountpoint(1)
+ * from sysvinit project.
*/
-
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include "xalloc.h"
#include "c.h"
#include "closestream.h"
+#include "pathnames.h"
-static int quiet;
+#define MOUNTPOINT_EXIT_NOMNT 32
-static int dir_to_device(const char *spec, dev_t *dev)
+struct mountpoint_control {
+ char *path;
+ dev_t dev;
+ struct stat st;
+ unsigned int
+ dev_devno:1,
+ fs_devno:1,
+ nofollow:1,
+ quiet:1;
+};
+
+static int dir_to_device(struct mountpoint_control *ctl)
{
- struct libmnt_table *tb = mnt_new_table_from_file("/proc/self/mountinfo");
+ struct libmnt_table *tb = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO);
struct libmnt_fs *fs;
struct libmnt_cache *cache;
int rc = -1;
* Fallback. Traditional way to detect mountpoints. This way
* is independent on /proc, but not able to detect bind mounts.
*/
- struct stat pst, st;
+ struct stat pst;
char buf[PATH_MAX], *cn;
int len;
- if (stat(spec, &st) != 0)
- return -1;
-
- cn = mnt_resolve_path(spec, NULL); /* canonicalize */
+ cn = mnt_resolve_path(ctl->path, NULL); /* canonicalize */
- len = snprintf(buf, sizeof(buf), "%s/..", cn ? cn : spec);
+ len = snprintf(buf, sizeof(buf), "%s/..", cn ? cn : ctl->path);
free(cn);
- if (len < 0 || (size_t) len + 1 > sizeof(buf))
+ if (len < 0 || (size_t) len >= sizeof(buf))
return -1;
if (stat(buf, &pst) !=0)
return -1;
- if ((st.st_dev != pst.st_dev) ||
- (st.st_dev == pst.st_dev && st.st_ino == pst.st_ino)) {
- *dev = st.st_dev;
+ if (ctl->st.st_dev != pst.st_dev || ctl->st.st_ino == pst.st_ino) {
+ ctl->dev = ctl->st.st_dev;
return 0;
}
/* to canonicalize all necessary paths */
cache = mnt_new_cache();
mnt_table_set_cache(tb, cache);
+ mnt_unref_cache(cache);
- fs = mnt_table_find_target(tb, spec, MNT_ITER_BACKWARD);
+ fs = mnt_table_find_target(tb, ctl->path, MNT_ITER_BACKWARD);
if (fs && mnt_fs_get_target(fs)) {
- *dev = mnt_fs_get_devno(fs);
+ ctl->dev = mnt_fs_get_devno(fs);
rc = 0;
}
- mnt_free_table(tb);
- mnt_free_cache(cache);
+ mnt_unref_table(tb);
return rc;
}
-static int print_devno(const char *devname, struct stat *st)
+static int print_devno(const struct mountpoint_control *ctl)
{
- struct stat stbuf;
-
- if (!st && stat(devname, &stbuf) == 0)
- st = &stbuf;
- if (!st)
- return -1;
- if (!S_ISBLK(st->st_mode)) {
- if (!quiet)
- warnx(_("%s: not a block device"), devname);
+ if (!S_ISBLK(ctl->st.st_mode)) {
+ if (!ctl->quiet)
+ warnx(_("%s: not a block device"), ctl->path);
return -1;
}
- printf("%u:%u\n", major(st->st_rdev), minor(st->st_rdev));
+ printf("%u:%u\n", major(ctl->st.st_rdev), minor(ctl->st.st_rdev));
return 0;
}
-static void __attribute__((__noreturn__)) usage(FILE *out)
+static void __attribute__((__noreturn__)) usage(void)
{
+ FILE *out = stdout;
fputs(USAGE_HEADER, out);
fprintf(out,
_(" %1$s [-qd] /path/to/directory\n"
" %1$s -x /dev/device\n"), program_invocation_short_name);
+ fputs(USAGE_SEPARATOR, out);
+ fputs(_("Check whether a directory or file is a mountpoint.\n"), out);
+
fputs(USAGE_OPTIONS, out);
fputs(_(" -q, --quiet quiet mode - don't print anything\n"
+ " --nofollow do not follow symlink\n"
" -d, --fs-devno print maj:min device number of the filesystem\n"
" -x, --devno print maj:min device number of the block device\n"), out);
fputs(USAGE_SEPARATOR, out);
- fputs(USAGE_HELP, out);
- fputs(USAGE_VERSION, out);
+ fprintf(out, USAGE_HELP_OPTIONS(20));
fprintf(out, USAGE_MAN_TAIL("mountpoint(1)"));
- exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+ exit(EXIT_SUCCESS);
}
int main(int argc, char **argv)
{
- int c, fs_devno = 0, dev_devno = 0, rc = 0;
- char *spec;
- struct stat st;
+ int c;
+ struct mountpoint_control ctl = { NULL };
+
+ enum {
+ OPT_NOFOLLOW = CHAR_MAX + 1
+ };
static const struct option longopts[] = {
- { "quiet", 0, 0, 'q' },
- { "fs-devno", 0, 0, 'd' },
- { "devno", 0, 0, 'x' },
- { "help", 0, 0, 'h' },
- { "version", 0, 0, 'V' },
- { NULL, 0, 0, 0 }
+ { "quiet", no_argument, NULL, 'q' },
+ { "nofollow", no_argument, NULL, OPT_NOFOLLOW },
+ { "fs-devno", no_argument, NULL, 'd' },
+ { "devno", no_argument, NULL, 'x' },
+ { "help", no_argument, NULL, 'h' },
+ { "version", no_argument, NULL, 'V' },
+ { NULL, 0, NULL, 0 }
};
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
- atexit(close_stdout);
+ close_stdout_atexit();
mnt_init_debug(0);
switch(c) {
case 'q':
- quiet = 1;
+ ctl.quiet = 1;
+ break;
+ case OPT_NOFOLLOW:
+ ctl.nofollow = 1;
break;
case 'd':
- fs_devno = 1;
+ ctl.fs_devno = 1;
break;
case 'x':
- dev_devno = 1;
+ ctl.dev_devno = 1;
break;
+
case 'h':
- usage(stdout);
- break;
+ usage();
case 'V':
- printf(UTIL_LINUX_VERSION);
- return EXIT_SUCCESS;
+ print_version(EXIT_SUCCESS);
default:
- usage(stderr);
- break;
+ errtryhelp(EXIT_FAILURE);
}
}
- if (optind + 1 != argc)
- usage(stderr);
-
- spec = argv[optind++];
-
- if (stat(spec, &st)) {
- if (!quiet)
- err(EXIT_FAILURE, "%s", spec);
+ if (optind + 1 != argc) {
+ warnx(_("bad usage"));
+ errtryhelp(EXIT_FAILURE);
+ }
+ if (ctl.nofollow && ctl.dev_devno)
+ errx(EXIT_FAILURE, _("%s and %s are mutually exclusive"),
+ "--devno", "--nofollow");
+
+ ctl.path = argv[optind];
+ c = ctl.nofollow ? lstat(ctl.path, &ctl.st) : stat(ctl.path, &ctl.st);
+ if (c) {
+ if (!ctl.quiet)
+ err(EXIT_FAILURE, "%s", ctl.path);
return EXIT_FAILURE;
}
- if (dev_devno)
- rc = print_devno(spec, &st);
- else {
- dev_t src;
-
- if (!S_ISDIR(st.st_mode)) {
- if (!quiet)
- errx(EXIT_FAILURE, _("%s: not a directory"), spec);
- return EXIT_FAILURE;
- }
+ if (ctl.dev_devno)
+ return print_devno(&ctl) ? MOUNTPOINT_EXIT_NOMNT : EXIT_SUCCESS;
- if ( dir_to_device(spec, &src)) {
- if (!quiet)
- printf(_("%s is not a mountpoint\n"), spec);
- return EXIT_FAILURE;
- }
- if (fs_devno)
- printf("%u:%u\n", major(src), minor(src));
- else if (!quiet)
- printf(_("%s is a mountpoint\n"), spec);
+ if ((ctl.nofollow && S_ISLNK(ctl.st.st_mode)) || dir_to_device(&ctl)) {
+ if (!ctl.quiet)
+ printf(_("%s is not a mountpoint\n"), ctl.path);
+ return MOUNTPOINT_EXIT_NOMNT;
}
+ if (ctl.fs_devno)
+ printf("%u:%u\n", major(ctl.dev), minor(ctl.dev));
+ else if (!ctl.quiet)
+ printf(_("%s is a mountpoint\n"), ctl.path);
- return rc ? EXIT_FAILURE : EXIT_SUCCESS;
+ return EXIT_SUCCESS;
}
projects / thirdparty / util-linux.git / blobdiff