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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 19:10:49 +0000
commitcfe5e3905201349e9cf3f95d52ff4bd100bde37d (patch)
treed0baf160cbee3195249d095f85e52d20c21acf02 /sys-utils/mountpoint.c
parentInitial commit. (diff)
downloadutil-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.tar.xz
util-linux-cfe5e3905201349e9cf3f95d52ff4bd100bde37d.zip
Adding upstream version 2.39.3.upstream/2.39.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sys-utils/mountpoint.c')
-rw-r--r--sys-utils/mountpoint.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/sys-utils/mountpoint.c b/sys-utils/mountpoint.c
new file mode 100644
index 0000000..b9904f3
--- /dev/null
+++ b/sys-utils/mountpoint.c
@@ -0,0 +1,219 @@
+/*
+ * mountpoint(1) - see if a directory is a mountpoint
+ *
+ * This is libmount based reimplementation of the mountpoint(1)
+ * from sysvinit project.
+ *
+ *
+ * Copyright (C) 2011 Red Hat, Inc. All rights reserved.
+ * Written by Karel Zak <kzak@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * 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.
+ *
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <getopt.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <libmount.h>
+
+#include "nls.h"
+#include "xalloc.h"
+#include "c.h"
+#include "closestream.h"
+#include "pathnames.h"
+
+#define MOUNTPOINT_EXIT_NOMNT 32
+
+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(_PATH_PROC_MOUNTINFO);
+ struct libmnt_fs *fs;
+ struct libmnt_cache *cache;
+ int rc = -1;
+
+ if (!tb) {
+ /*
+ * Fallback. Traditional way to detect mountpoints. This way
+ * is independent on /proc, but not able to detect bind mounts.
+ */
+ struct stat pst;
+ char buf[PATH_MAX], *cn;
+ int len;
+
+ cn = mnt_resolve_path(ctl->path, NULL); /* canonicalize */
+
+ len = snprintf(buf, sizeof(buf), "%s/..", cn ? cn : ctl->path);
+ free(cn);
+
+ if (len < 0 || (size_t) len >= sizeof(buf))
+ return -1;
+ if (stat(buf, &pst) !=0)
+ return -1;
+
+ if (ctl->st.st_dev != pst.st_dev || ctl->st.st_ino == pst.st_ino) {
+ ctl->dev = ctl->st.st_dev;
+ return 0;
+ }
+
+ return -1;
+ }
+
+ /* 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, ctl->path, MNT_ITER_BACKWARD);
+ if (fs && mnt_fs_get_target(fs)) {
+ ctl->dev = mnt_fs_get_devno(fs);
+ rc = 0;
+ }
+
+ mnt_unref_table(tb);
+ return rc;
+}
+
+static int print_devno(const struct mountpoint_control *ctl)
+{
+ 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(ctl->st.st_rdev), minor(ctl->st.st_rdev));
+ return 0;
+}
+
+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);
+ printf(USAGE_HELP_OPTIONS(20));
+ printf(USAGE_MAN_TAIL("mountpoint(1)"));
+
+ exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char **argv)
+{
+ int c;
+ struct mountpoint_control ctl = { NULL };
+
+ enum {
+ OPT_NOFOLLOW = CHAR_MAX + 1
+ };
+
+ static const struct option longopts[] = {
+ { "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);
+ close_stdout_atexit();
+
+ mnt_init_debug(0);
+
+ while ((c = getopt_long(argc, argv, "qdxhV", longopts, NULL)) != -1) {
+
+ switch(c) {
+ case 'q':
+ ctl.quiet = 1;
+ break;
+ case OPT_NOFOLLOW:
+ ctl.nofollow = 1;
+ break;
+ case 'd':
+ ctl.fs_devno = 1;
+ break;
+ case 'x':
+ ctl.dev_devno = 1;
+ break;
+
+ case 'h':
+ usage();
+ case 'V':
+ print_version(EXIT_SUCCESS);
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ 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 (ctl.dev_devno)
+ return print_devno(&ctl) ? MOUNTPOINT_EXIT_NOMNT : EXIT_SUCCESS;
+
+ 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 EXIT_SUCCESS;
+}