1 /* vi: set sw=4 ts=4: */
3 * Mini mount implementation for busybox
5 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 * 3/21/1999 Charles P. Wright <cpwright@cpwright.com>
22 * searches through fstab when -a is passed
23 * will try mounting stuff with all fses when passed -t auto
25 * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab.
27 * 1999-10-07 Erik Andersen <andersen@lineo.com>, <andersee@debian.org>.
28 * Rewrite of a lot of code. Removed mtab usage (I plan on
29 * putting it back as a compile-time option some time),
30 * major adjustments to option parsing, and some serious
33 * 1999-11-06 mtab suppport is back - andersee
35 * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
36 * mount to add loop support.
46 #include <sys/mount.h>
50 #if defined BB_FEATURE_MOUNT_LOOP
52 #include <sys/ioctl.h>
53 #include <linux/loop.h>
56 static int use_loop = 0;
59 extern const char mtab_file[]; /* Defined in utility.c */
61 static const char mount_usage[] = "\tmount [flags]\n"
62 "\tmount [flags] device directory [-o options,more-options]\n"
63 "\n" "Flags:\n" "\t-a:\tMount all file systems in fstab.\n"
65 "\t-f:\t\"Fake\" mount. Add entry to mount table but don't mount it.\n"
66 "\t-n:\tDon't write a mount table entry.\n"
68 "\t-o option:\tOne of many filesystem options, listed below.\n"
69 "\t-r:\tMount the filesystem read-only.\n"
70 "\t-t filesystem-type:\tSpecify the filesystem type.\n"
71 "\t-w:\tMount for reading and writing (default).\n"
73 "Options for use with the \"-o\" flag:\n"
74 "\tasync / sync:\tWrites are asynchronous / synchronous.\n"
75 "\tdev / nodev:\tAllow use of special device files / disallow them.\n"
76 "\texec / noexec:\tAllow use of executable files / disallow them.\n"
77 #if defined BB_FEATURE_MOUNT_LOOP
78 "\tloop: Mounts a file via loop device.\n"
80 "\tsuid / nosuid:\tAllow set-user-id-root programs / disallow them.\n"
81 "\tremount: Re-mount a currently-mounted filesystem, changing its flags.\n"
82 "\tro / rw: Mount for read-only / read-write.\n"
85 "There are EVEN MORE flags that are specific to each filesystem.\n"
86 "You'll have to see the written documentation for those.\n";
89 struct mount_options {
95 static const struct mount_options mount_options[] = {
96 {"async", ~MS_SYNCHRONOUS, 0},
98 {"dev", ~MS_NODEV, 0},
99 {"exec", ~MS_NOEXEC, 0},
100 {"nodev", ~0, MS_NODEV},
101 {"noexec", ~0, MS_NOEXEC},
102 {"nosuid", ~0, MS_NOSUID},
103 {"remount", ~0, MS_REMOUNT},
104 {"ro", ~0, MS_RDONLY},
105 {"rw", ~MS_RDONLY, 0},
106 {"suid", ~MS_NOSUID, 0},
107 {"sync", ~0, MS_SYNCHRONOUS},
112 do_mount(char *specialfile, char *dir, char *filesystemtype,
113 long flags, void *string_flags, int useMtab, int fakeIt,
122 #if defined BB_FEATURE_MOUNT_LOOP
124 int loro = flags & MS_RDONLY;
125 char *lofile = specialfile;
127 specialfile = find_unused_loop_device();
128 if (specialfile == NULL) {
129 fprintf(stderr, "Could not find a spare loop device\n");
132 if (set_loop(specialfile, lofile, 0, &loro)) {
133 fprintf(stderr, "Could not setup loop device\n");
136 if (!(flags & MS_RDONLY) && loro) { /* loop is ro, but wanted rw */
137 fprintf(stderr, "WARNING: loop device is read-only\n");
143 mount(specialfile, dir, filesystemtype, flags, string_flags);
147 /* If the mount was sucessful, do anything needed, then return TRUE */
151 if (useMtab == TRUE) {
152 write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
158 /* Bummer. mount failed. Clean up */
159 #if defined BB_FEATURE_MOUNT_LOOP
160 if (specialfile != NULL) {
161 del_loop(specialfile);
170 #define whine_if_fstab_is_missing() {}
172 extern void whine_if_fstab_is_missing()
176 if (stat("/etc/fstab", &statBuf) < 0)
178 "/etc/fstab file missing -- install one to name /dev/root.\n\n");
183 /* Seperate standard mount options from the nonstandard string options */
185 parse_mount_options(char *options, unsigned long *flags, char *strflags)
189 char *comma = strchr(options, ',');
190 const struct mount_options *f = mount_options;
195 while (f->name != 0) {
196 if (strcasecmp(f->name, options) == 0) {
205 #if defined BB_FEATURE_MOUNT_LOOP
206 if (gotone == FALSE && !strcasecmp("loop", options)) { /* loop device support */
211 if (*strflags && strflags != '\0' && gotone == FALSE) {
212 char *temp = strflags;
214 temp += strlen(strflags);
219 strcat(strflags, options);
230 mount_one(char *blockDevice, char *directory, char *filesystemType,
231 unsigned long flags, char *string_flags, int useMtab, int fakeIt,
238 #if defined BB_FEATURE_USE_PROCFS
239 if (strcmp(filesystemType, "auto") == 0) {
240 FILE *f = fopen("/proc/filesystems", "r");
245 while (fgets(buf, sizeof(buf), f) != NULL) {
246 filesystemType = buf;
247 if (*filesystemType == '\t') { // Not a nodev filesystem
249 // Add NULL termination to each line
250 while (*filesystemType && *filesystemType != '\n')
252 *filesystemType = '\0';
254 filesystemType = buf;
255 filesystemType++; // hop past tab
257 status = do_mount(blockDevice, directory, filesystemType,
258 flags | MS_MGC_VAL, string_flags,
259 useMtab, fakeIt, mtab_opts);
268 status = do_mount(blockDevice, directory, filesystemType,
269 flags | MS_MGC_VAL, string_flags, useMtab,
273 if (status == FALSE) {
274 fprintf(stderr, "Mounting %s on %s failed: %s\n",
275 blockDevice, directory, strerror(errno));
281 extern int mount_main(int argc, char **argv)
283 char string_flags_buf[1024] = "";
284 char *string_flags = string_flags_buf;
285 char *extra_opts = string_flags_buf;
286 unsigned long flags = 0;
287 char *filesystemType = "auto";
289 char *directory = NULL;
295 /* Only compiled in if BB_MTAB is not defined */
296 whine_if_fstab_is_missing();
299 FILE *mountTable = setmntent(mtab_file, "r");
304 while ((m = getmntent(mountTable)) != 0) {
305 struct fstab *fstabItem;
306 char *blockDevice = m->mnt_fsname;
308 /* Note that if /etc/fstab is missing, libc can't fix up /dev/root for us */
309 if (strcmp(blockDevice, "/dev/root") == 0) {
310 fstabItem = getfsfile("/");
311 if (fstabItem != NULL)
312 blockDevice = fstabItem->fs_spec;
314 printf("%s on %s type %s (%s)\n", blockDevice, m->mnt_dir,
315 m->mnt_type, m->mnt_opts);
317 endmntent(mountTable);
328 while (i > 0 && **argv) {
332 while (i > 0 && *++opt)
338 parse_mount_options(*(++argv), &flags, string_flags);
347 filesystemType = *(++argv);
371 else if (directory == NULL)
383 FILE *f = setmntent("/etc/fstab", "r");
386 perror("/etc/fstab");
389 while ((m = getmntent(f)) != NULL) {
390 // If the file system isn't noauto, and isn't mounted on /,
391 // and isn't swap or nfs, then mount it
392 if ((!strstr(m->mnt_opts, "noauto")) &&
393 (m->mnt_dir[1] != '\0') &&
394 (!strstr(m->mnt_type, "swap")) &&
395 (!strstr(m->mnt_type, "nfs"))) {
397 *string_flags = '\0';
398 parse_mount_options(m->mnt_opts, &flags, string_flags);
399 mount_one(m->mnt_fsname, m->mnt_dir, m->mnt_type,
400 flags, string_flags, useMtab, fakeIt,
406 if (device && directory) {
408 if (strcmp(filesystemType, "nfs") == 0) {
410 (device, directory, &flags, &extra_opts, &string_flags,
415 exit(mount_one(device, directory, filesystemType,
416 flags, string_flags, useMtab, fakeIt,