| /* |
| * 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" |
| |
| struct mountpoint_control { |
| char *path; |
| dev_t dev; |
| struct stat st; |
| unsigned int |
| dev_devno:1, |
| fs_devno: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" |
| " -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 }; |
| |
| static const struct option longopts[] = { |
| { "quiet", no_argument, NULL, 'q' }, |
| { "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); |
| |
| mnt_init_debug(0); |
| |
| while ((c = getopt_long(argc, argv, "qdxhV", longopts, NULL)) != -1) { |
| |
| switch(c) { |
| case 'q': |
| ctl.quiet = 1; |
| break; |
| case 'd': |
| ctl.fs_devno = 1; |
| break; |
| case 'x': |
| ctl.dev_devno = 1; |
| break; |
| case 'h': |
| usage(); |
| break; |
| case 'V': |
| printf(UTIL_LINUX_VERSION); |
| return EXIT_SUCCESS; |
| default: |
| errtryhelp(EXIT_FAILURE); |
| } |
| } |
| |
| if (optind + 1 != argc) { |
| warnx(_("bad usage")); |
| errtryhelp(EXIT_FAILURE); |
| } |
| |
| ctl.path = argv[optind]; |
| |
| if (stat(ctl.path, &ctl.st)) { |
| if (!ctl.quiet) |
| err(EXIT_FAILURE, "%s", ctl.path); |
| return EXIT_FAILURE; |
| } |
| if (ctl.dev_devno) |
| return print_devno(&ctl) ? EXIT_FAILURE : EXIT_SUCCESS; |
| if (dir_to_device(&ctl)) { |
| if (!ctl.quiet) |
| printf(_("%s is not a mountpoint\n"), ctl.path); |
| return EXIT_FAILURE; |
| } |
| 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; |
| } |