]>
Commit | Line | Data |
---|---|---|
2a1d943d KZ |
1 | /* |
2 | * mountpoint(1) - see if a directory is a mountpoint | |
3 | * | |
9e930041 | 4 | * This is libmount based reimplementation of the mountpoint(1) |
2a1d943d KZ |
5 | * from sysvinit project. |
6 | * | |
7 | * | |
8 | * Copyright (C) 2011 Red Hat, Inc. All rights reserved. | |
9 | * Written by Karel Zak <kzak@redhat.com> | |
10 | * | |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2 of the License, or | |
14 | * (at your option) any later version. | |
15 | * | |
16 | * This program is distributed in the hope that it would be useful, | |
17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | * GNU General Public License for more details. | |
20 | * | |
7cebf0bb SK |
21 | * You should have received a copy of the GNU General Public License along |
22 | * with this program; if not, write to the Free Software Foundation, Inc., | |
23 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
2a1d943d KZ |
24 | */ |
25 | ||
26 | #include <stdio.h> | |
27 | #include <stdlib.h> | |
28 | #include <errno.h> | |
29 | #include <string.h> | |
30 | #include <getopt.h> | |
31 | #include <unistd.h> | |
32 | #include <sys/types.h> | |
33 | #include <sys/stat.h> | |
2a1d943d KZ |
34 | |
35 | #include <libmount.h> | |
36 | ||
37 | #include "nls.h" | |
38 | #include "xalloc.h" | |
39 | #include "c.h" | |
efb8854f | 40 | #include "closestream.h" |
39edf681 | 41 | #include "pathnames.h" |
2a1d943d | 42 | |
f112f41e SK |
43 | struct mountpoint_control { |
44 | char *path; | |
45 | dev_t dev; | |
46 | struct stat st; | |
47 | unsigned int | |
48 | dev_devno:1, | |
49 | fs_devno:1, | |
50 | quiet:1; | |
51 | }; | |
2a1d943d | 52 | |
f112f41e | 53 | static int dir_to_device(struct mountpoint_control *ctl) |
2a1d943d | 54 | { |
39edf681 | 55 | struct libmnt_table *tb = mnt_new_table_from_file(_PATH_PROC_MOUNTINFO); |
2a1d943d | 56 | struct libmnt_fs *fs; |
eb9d3706 | 57 | struct libmnt_cache *cache; |
eac83fbc | 58 | int rc = -1; |
2a1d943d | 59 | |
dfd2c714 KZ |
60 | if (!tb) { |
61 | /* | |
62 | * Fallback. Traditional way to detect mountpoints. This way | |
63 | * is independent on /proc, but not able to detect bind mounts. | |
64 | */ | |
f112f41e | 65 | struct stat pst; |
eb9d3706 | 66 | char buf[PATH_MAX], *cn; |
dfd2c714 KZ |
67 | int len; |
68 | ||
f112f41e | 69 | cn = mnt_resolve_path(ctl->path, NULL); /* canonicalize */ |
eb9d3706 | 70 | |
f112f41e | 71 | len = snprintf(buf, sizeof(buf), "%s/..", cn ? cn : ctl->path); |
eb9d3706 KZ |
72 | free(cn); |
73 | ||
06fa5817 | 74 | if (len < 0 || (size_t) len >= sizeof(buf)) |
04f087ec | 75 | return -1; |
dfd2c714 | 76 | if (stat(buf, &pst) !=0) |
04f087ec | 77 | return -1; |
dfd2c714 | 78 | |
f112f41e SK |
79 | if ((ctl->st.st_dev != pst.st_dev) || |
80 | (ctl->st.st_dev == pst.st_dev && ctl->st.st_ino == pst.st_ino)) { | |
81 | ctl->dev = ctl->st.st_dev; | |
04f087ec ZL |
82 | return 0; |
83 | } | |
dfd2c714 | 84 | |
04f087ec | 85 | return -1; |
dfd2c714 | 86 | } |
2a1d943d | 87 | |
eb9d3706 KZ |
88 | /* to canonicalize all necessary paths */ |
89 | cache = mnt_new_cache(); | |
90 | mnt_table_set_cache(tb, cache); | |
6195f9e6 | 91 | mnt_unref_cache(cache); |
eb9d3706 | 92 | |
f112f41e | 93 | fs = mnt_table_find_target(tb, ctl->path, MNT_ITER_BACKWARD); |
eac83fbc | 94 | if (fs && mnt_fs_get_target(fs)) { |
f112f41e | 95 | ctl->dev = mnt_fs_get_devno(fs); |
eac83fbc DR |
96 | rc = 0; |
97 | } | |
2a1d943d | 98 | |
50fccba1 | 99 | mnt_unref_table(tb); |
eac83fbc | 100 | return rc; |
2a1d943d KZ |
101 | } |
102 | ||
f112f41e | 103 | static int print_devno(const struct mountpoint_control *ctl) |
2a1d943d | 104 | { |
f112f41e SK |
105 | if (!S_ISBLK(ctl->st.st_mode)) { |
106 | if (!ctl->quiet) | |
107 | warnx(_("%s: not a block device"), ctl->path); | |
2a1d943d KZ |
108 | return -1; |
109 | } | |
f112f41e | 110 | printf("%u:%u\n", major(ctl->st.st_rdev), minor(ctl->st.st_rdev)); |
2a1d943d KZ |
111 | return 0; |
112 | } | |
113 | ||
114 | static void __attribute__((__noreturn__)) usage(FILE *out) | |
115 | { | |
30b61b7b | 116 | fputs(USAGE_HEADER, out); |
4f92adb6 KZ |
117 | fprintf(out, |
118 | _(" %1$s [-qd] /path/to/directory\n" | |
119 | " %1$s -x /dev/device\n"), program_invocation_short_name); | |
120 | ||
451dbcfa BS |
121 | fputs(USAGE_SEPARATOR, out); |
122 | fputs(_("Check whether a directory or file is a mountpoint.\n"), out); | |
123 | ||
30b61b7b | 124 | fputs(USAGE_OPTIONS, out); |
4f92adb6 KZ |
125 | fputs(_(" -q, --quiet quiet mode - don't print anything\n" |
126 | " -d, --fs-devno print maj:min device number of the filesystem\n" | |
30b61b7b SK |
127 | " -x, --devno print maj:min device number of the block device\n"), out); |
128 | fputs(USAGE_SEPARATOR, out); | |
129 | fputs(USAGE_HELP, out); | |
130 | fputs(USAGE_VERSION, out); | |
131 | fprintf(out, USAGE_MAN_TAIL("mountpoint(1)")); | |
2a1d943d KZ |
132 | |
133 | exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS); | |
134 | } | |
135 | ||
136 | int main(int argc, char **argv) | |
137 | { | |
ee5de88c | 138 | int c; |
f112f41e | 139 | struct mountpoint_control ctl = { 0 }; |
2a1d943d KZ |
140 | |
141 | static const struct option longopts[] = { | |
142 | { "quiet", 0, 0, 'q' }, | |
143 | { "fs-devno", 0, 0, 'd' }, | |
144 | { "devno", 0, 0, 'x' }, | |
145 | { "help", 0, 0, 'h' }, | |
30b61b7b | 146 | { "version", 0, 0, 'V' }, |
2a1d943d KZ |
147 | { NULL, 0, 0, 0 } |
148 | }; | |
149 | ||
150 | setlocale(LC_ALL, ""); | |
151 | bindtextdomain(PACKAGE, LOCALEDIR); | |
152 | textdomain(PACKAGE); | |
efb8854f | 153 | atexit(close_stdout); |
2a1d943d KZ |
154 | |
155 | mnt_init_debug(0); | |
156 | ||
30b61b7b | 157 | while ((c = getopt_long(argc, argv, "qdxhV", longopts, NULL)) != -1) { |
2a1d943d KZ |
158 | |
159 | switch(c) { | |
160 | case 'q': | |
f112f41e | 161 | ctl.quiet = 1; |
2a1d943d KZ |
162 | break; |
163 | case 'd': | |
f112f41e | 164 | ctl.fs_devno = 1; |
2a1d943d KZ |
165 | break; |
166 | case 'x': | |
f112f41e | 167 | ctl.dev_devno = 1; |
2a1d943d KZ |
168 | break; |
169 | case 'h': | |
170 | usage(stdout); | |
171 | break; | |
30b61b7b SK |
172 | case 'V': |
173 | printf(UTIL_LINUX_VERSION); | |
174 | return EXIT_SUCCESS; | |
2a1d943d KZ |
175 | default: |
176 | usage(stderr); | |
177 | break; | |
178 | } | |
179 | } | |
180 | ||
181 | if (optind + 1 != argc) | |
182 | usage(stderr); | |
183 | ||
f112f41e | 184 | ctl.path = argv[optind]; |
2a1d943d | 185 | |
f112f41e SK |
186 | if (stat(ctl.path, &ctl.st)) { |
187 | if (!ctl.quiet) | |
188 | err(EXIT_FAILURE, "%s", ctl.path); | |
b031befc | 189 | return EXIT_FAILURE; |
2a1d943d | 190 | } |
f112f41e | 191 | if (ctl.dev_devno) |
ee5de88c SK |
192 | return print_devno(&ctl) ? EXIT_FAILURE : EXIT_SUCCESS; |
193 | if (dir_to_device(&ctl)) { | |
194 | if (!ctl.quiet) | |
195 | printf(_("%s is not a mountpoint\n"), ctl.path); | |
196 | return EXIT_FAILURE; | |
2a1d943d | 197 | } |
ee5de88c SK |
198 | if (ctl.fs_devno) |
199 | printf("%u:%u\n", major(ctl.dev), minor(ctl.dev)); | |
200 | else if (!ctl.quiet) | |
201 | printf(_("%s is a mountpoint\n"), ctl.path); | |
202 | return EXIT_SUCCESS; | |
2a1d943d | 203 | } |