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busybox/util-linux/mount.c
Glenn L McGrath 9fef17dec3 Run through indent, fix comments
2002-08-22 18:41:20 +00:00

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/* vi: set sw=4 ts=4: */
/*
* Mini mount implementation for busybox
*
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
* Copyright (C) 1999-2002 by Erik Andersen <andersee@debian.org>
*
* 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 will 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* 3/21/1999 Charles P. Wright <cpwright@cpwright.com>
* searches through fstab when -a is passed
* will try mounting stuff with all fses when passed -t auto
*
* 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab.
*
* 1999-10-07 Erik Andersen <andersee@debian.org>.
* Rewrite of a lot of code. Removed mtab usage (I plan on
* putting it back as a compile-time option some time),
* major adjustments to option parsing, and some serious
* dieting all around.
*
* 1999-11-06 mtab suppport is back - andersee
*
* 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
* mount to add loop support.
*
* 2000-04-30 Dave Cinege <dcinege@psychosis.com>
* Rewrote fstab while loop and lower mount section. Can now do
* single mounts from fstab. Can override fstab options for single
* mount. Common mount_one call for single mounts and 'all'. Fixed
* mtab updating and stale entries. Removed 'remount' default.
*
*/
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <mntent.h>
#include <ctype.h>
#include "busybox.h"
#if defined CONFIG_FEATURE_USE_DEVPS_PATCH
# include <linux/devmtab.h> /* For Erik's nifty devmtab device driver */
#endif
enum {
MS_MGC_VAL = 0xc0ed0000, /* Magic number indicatng "new" flags */
MS_RDONLY = 1, /* Mount read-only */
MS_NOSUID = 2, /* Ignore suid and sgid bits */
MS_NODEV = 4, /* Disallow access to device special files */
MS_NOEXEC = 8, /* Disallow program execution */
MS_SYNCHRONOUS = 16, /* Writes are synced at once */
MS_REMOUNT = 32, /* Alter flags of a mounted FS */
MS_MANDLOCK = 64, /* Allow mandatory locks on an FS */
S_QUOTA = 128, /* Quota initialized for file/directory/symlink */
S_APPEND = 256, /* Append-only file */
S_IMMUTABLE = 512, /* Immutable file */
MS_NOATIME = 1024, /* Do not update access times. */
MS_NODIRATIME = 2048, /* Do not update directory access times */
MS_BIND = 4096, /* Use the new linux 2.4.x "mount --bind" feature */
};
#if defined CONFIG_FEATURE_MOUNT_LOOP
#include <fcntl.h>
#include <sys/ioctl.h>
static int use_loop = FALSE;
#endif
extern int mount(__const char *__special_file, __const char *__dir,
__const char *__fstype, unsigned long int __rwflag,
__const void *__data);
extern int umount(__const char *__special_file);
extern int umount2(__const char *__special_file, int __flags);
extern int sysfs(int option, unsigned int fs_index, char *buf);
extern const char mtab_file[]; /* Defined in utility.c */
struct mount_options {
const char *name;
unsigned long and;
unsigned long or;
};
static const struct mount_options mount_options[] = {
{"async", ~MS_SYNCHRONOUS, 0},
{"atime", ~0, ~MS_NOATIME},
{"defaults", ~0, 0},
{"noauto", ~0, 0},
{"dev", ~MS_NODEV, 0},
{"diratime", ~0, ~MS_NODIRATIME},
{"exec", ~MS_NOEXEC, 0},
{"noatime", ~0, MS_NOATIME},
{"nodev", ~0, MS_NODEV},
{"nodiratime", ~0, MS_NODIRATIME},
{"noexec", ~0, MS_NOEXEC},
{"nosuid", ~0, MS_NOSUID},
{"remount", ~0, MS_REMOUNT},
{"ro", ~0, MS_RDONLY},
{"rw", ~MS_RDONLY, 0},
{"suid", ~MS_NOSUID, 0},
{"sync", ~0, MS_SYNCHRONOUS},
{"bind", ~0, MS_BIND},
{0, 0, 0}
};
static int
do_mount(char *specialfile, char *dir, char *filesystemtype,
long flags, void *string_flags, int useMtab, int fakeIt,
char *mtab_opts, int mount_all)
{
int status = 0;
#if defined CONFIG_FEATURE_MOUNT_LOOP
char *lofile = NULL;
#endif
if (!fakeIt) {
#if defined CONFIG_FEATURE_MOUNT_LOOP
if (use_loop == TRUE) {
int loro = flags & MS_RDONLY;
lofile = specialfile;
specialfile = find_unused_loop_device();
if (specialfile == NULL) {
error_msg_and_die("Could not find a spare loop device");
}
if (set_loop(specialfile, lofile, 0, &loro)) {
error_msg_and_die("Could not setup loop device");
}
if (!(flags & MS_RDONLY) && loro) { /* loop is ro, but wanted rw */
error_msg("WARNING: loop device is read-only");
flags |= MS_RDONLY;
}
}
#endif
status = mount(specialfile, dir, filesystemtype, flags, string_flags);
if (status < 0 && errno == EROFS) {
error_msg("%s is write-protected, mounting read-only",
specialfile);
status = mount(specialfile, dir, filesystemtype, flags |=
MS_RDONLY, string_flags);
}
/* Don't whine about already mounted filesystems when mounting all. */
if (status < 0 && errno == EBUSY && mount_all)
return TRUE;
}
/* If the mount was sucessful, do anything needed, then return TRUE */
if (status == 0 || fakeIt == TRUE) {
#if defined CONFIG_FEATURE_MTAB_SUPPORT
if (useMtab) {
erase_mtab(specialfile); /* Clean any stale entries */
write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
}
#endif
return (TRUE);
}
/* Bummer. mount failed. Clean up */
#if defined CONFIG_FEATURE_MOUNT_LOOP
if (lofile != NULL) {
del_loop(specialfile);
}
#endif
if (errno == EPERM) {
error_msg_and_die("permission denied. Are you root?");
}
return (FALSE);
}
static void paste_str(char **s1, const char *s2)
{
*s1 = xrealloc(*s1, strlen(*s1) + strlen(s2) + 1);
strcat(*s1, s2);
}
/* Seperate standard mount options from the nonstandard string options */
static void parse_mount_options(char *options, int *flags, char **strflags)
{
while (options) {
int gotone = FALSE;
char *comma = strchr(options, ',');
const struct mount_options *f = mount_options;
if (comma)
*comma = '\0';
while (f->name != 0) {
if (strcasecmp(f->name, options) == 0) {
*flags &= f->and;
*flags |= f->or;
gotone = TRUE;
break;
}
f++;
}
#if defined CONFIG_FEATURE_MOUNT_LOOP
if (!strcasecmp("loop", options)) { /* loop device support */
use_loop = TRUE;
gotone = TRUE;
}
#endif
if (!gotone) {
if (**strflags) /* have previous parsed options */
paste_str(strflags, ",");
paste_str(strflags, options);
}
if (comma) {
*comma = ',';
options = ++comma;
} else {
break;
}
}
}
static int
mount_one(char *blockDevice, char *directory, char *filesystemType,
unsigned long flags, char *string_flags, int useMtab, int fakeIt,
char *mtab_opts, int whineOnErrors, int mount_all)
{
int status = 0;
#if defined CONFIG_FEATURE_USE_DEVPS_PATCH
if (strcmp(filesystemType, "auto") == 0) {
static const char *noauto_array[] =
{ "tmpfs", "shm", "proc", "ramfs", "devpts", "devfs", "usbdevfs",
0 };
const char **noauto_fstype;
const int num_of_filesystems = sysfs(3, 0, 0);
char buf[255];
int i = 0;
filesystemType = buf;
while (i < num_of_filesystems) {
sysfs(2, i++, filesystemType);
for (noauto_fstype = noauto_array; *noauto_fstype;
noauto_fstype++) {
if (!strcmp(filesystemType, *noauto_fstype)) {
break;
}
}
if (!*noauto_fstype) {
status = do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags,
useMtab, fakeIt, mtab_opts, mount_all);
if (status)
break;
}
}
}
#else
if (strcmp(filesystemType, "auto") == 0) {
char buf[255];
FILE *f;
int read_proc = 0;
f = fopen("/etc/filesystems", "r");
if (f) {
while (fgets(buf, sizeof(buf), f)) {
if (*buf == '*')
read_proc = 1;
else if (*buf == '#')
continue;
else {
filesystemType = buf;
/* Add NULL termination to each line */
while (*filesystemType && !isspace(*filesystemType))
filesystemType++;
*filesystemType = '\0';
filesystemType = buf;
if (xstrlen(filesystemType)) {
status =
do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags,
useMtab, fakeIt, mtab_opts, mount_all);
if (status)
break;
}
}
}
fclose(f);
}
if ((!f || read_proc) && !status) {
f = xfopen("/proc/filesystems", "r");
while (fgets(buf, sizeof(buf), f) != NULL) {
filesystemType = buf;
if (*filesystemType == '\t') { /* Not a nodev filesystem */
/* Add NULL termination to each line */
while (*filesystemType && *filesystemType != '\n')
filesystemType++;
*filesystemType = '\0';
filesystemType = buf;
filesystemType++; /* hop past tab */
status = do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags,
useMtab, fakeIt, mtab_opts, mount_all);
if (status)
break;
}
}
}
fclose(f);
}
#endif
else {
status = do_mount(blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags, useMtab,
fakeIt, mtab_opts, mount_all);
}
if (!status) {
if (whineOnErrors) {
perror_msg("Mounting %s on %s failed", blockDevice, directory);
}
return (FALSE);
}
return (TRUE);
}
static void show_mounts(char *onlytype)
{
#if defined CONFIG_FEATURE_USE_DEVPS_PATCH
int fd, i, numfilesystems;
char device[] = "/dev/mtab";
struct k_mntent *mntentlist;
/* open device */
fd = open(device, O_RDONLY);
if (fd < 0)
perror_msg_and_die("open failed for `%s'", device);
/* How many mounted filesystems? We need to know to
* allocate enough space for later... */
numfilesystems = ioctl(fd, DEVMTAB_COUNT_MOUNTS);
if (numfilesystems < 0)
perror_msg_and_die("\nDEVMTAB_COUNT_MOUNTS");
mntentlist =
(struct k_mntent *) xcalloc(numfilesystems, sizeof(struct k_mntent));
/* Grab the list of mounted filesystems */
if (ioctl(fd, DEVMTAB_GET_MOUNTS, mntentlist) < 0)
perror_msg_and_die("\nDEVMTAB_GET_MOUNTS");
for (i = 0; i < numfilesystems; i++) {
if (!onlytype || (strcmp(mntentlist[i].mnt_type, onlytype) == 0)) {
printf("%s %s %s %s %d %d\n", mntentlist[i].mnt_fsname,
mntentlist[i].mnt_dir, mntentlist[i].mnt_type,
mntentlist[i].mnt_opts, mntentlist[i].mnt_freq,
mntentlist[i].mnt_passno);
}
}
#ifdef CONFIG_FEATURE_CLEAN_UP
/* Don't bother to close files or free memory. Exit
* does that automagically, so we can save a few bytes */
free(mntentlist);
close(fd);
#endif
exit(EXIT_SUCCESS);
#else
FILE *mountTable = setmntent(mtab_file, "r");
if (mountTable) {
struct mntent *m;
while ((m = getmntent(mountTable)) != 0) {
char *blockDevice = m->mnt_fsname;
if (strcmp(blockDevice, "/dev/root") == 0) {
blockDevice = find_real_root_device_name(blockDevice);
}
if (!onlytype || (strcmp(m->mnt_type, onlytype) == 0)) {
printf("%s on %s type %s (%s)\n", blockDevice, m->mnt_dir,
m->mnt_type, m->mnt_opts);
}
#ifdef CONFIG_FEATURE_CLEAN_UP
if (blockDevice != m->mnt_fsname)
free(blockDevice);
#endif
}
endmntent(mountTable);
} else {
perror_msg_and_die("%s", mtab_file);
}
exit(EXIT_SUCCESS);
#endif
}
extern int mount_main(int argc, char **argv)
{
struct stat statbuf;
char *string_flags = xstrdup("");
char *extra_opts;
int flags = 0;
char *filesystemType = "auto";
int got_filesystemType = 0;
char *device = xmalloc(PATH_MAX);
char *directory = xmalloc(PATH_MAX);
struct mntent *m = NULL;
int all = FALSE;
int fakeIt = FALSE;
int useMtab = TRUE;
int rc = EXIT_FAILURE;
FILE *f = 0;
int opt;
/* Parse options */
while ((opt = getopt(argc, argv, "o:rt:wafnv")) > 0) {
switch (opt) {
case 'o':
parse_mount_options(optarg, &flags, &string_flags);
break;
case 'r':
flags |= MS_RDONLY;
break;
case 't':
filesystemType = optarg;
got_filesystemType = 1;
break;
case 'w':
flags &= ~MS_RDONLY;
break;
case 'a':
all = TRUE;
break;
case 'f':
fakeIt = TRUE;
break;
#ifdef CONFIG_FEATURE_MTAB_SUPPORT
case 'n':
useMtab = FALSE;
break;
#endif
case 'v':
break; /* ignore -v */
}
}
if (!all && optind == argc)
show_mounts(got_filesystemType ? filesystemType : 0);
if (optind < argc) {
/* if device is a filename get its real path */
if (stat(argv[optind], &statbuf) == 0) {
char *tmp = simplify_path(argv[optind]);
safe_strncpy(device, tmp, PATH_MAX);
} else {
safe_strncpy(device, argv[optind], PATH_MAX);
}
}
if (optind + 1 < argc)
directory = simplify_path(argv[optind + 1]);
if (all || optind + 1 == argc) {
f = setmntent("/etc/fstab", "r");
if (f == NULL)
perror_msg_and_die("\nCannot read /etc/fstab");
while ((m = getmntent(f)) != NULL) {
if (!all && optind + 1 == argc && ((strcmp(device, m->mnt_fsname)
!= 0)
&& (strcmp(device, m->mnt_dir)
!= 0))) {
continue;
}
if (all && ( /* If we're mounting 'all' */
(strstr(m->mnt_opts, "noauto")) || /* and the file system isn't noauto, */
(strstr(m->mnt_type, "swap")) || /* and isn't swap or nfs, then mount it */
(strstr(m->mnt_type, "nfs")))) {
continue;
}
if (all || flags == 0) { /* Allow single mount to override fstab flags */
flags = 0;
string_flags[0] = 0;
parse_mount_options(m->mnt_opts, &flags, &string_flags);
}
strcpy(device, m->mnt_fsname);
strcpy(directory, m->mnt_dir);
filesystemType = xstrdup(m->mnt_type);
singlemount:
extra_opts = string_flags;
rc = EXIT_SUCCESS;
#ifdef CONFIG_NFSMOUNT
if (strchr(device, ':') != NULL) {
filesystemType = "nfs";
if (nfsmount(device, directory, &flags, &extra_opts,
&string_flags, 1)) {
perror_msg("nfsmount failed");
rc = EXIT_FAILURE;
}
}
#endif
if (!mount_one(device, directory, filesystemType, flags,
string_flags, useMtab, fakeIt, extra_opts, TRUE,
all))
rc = EXIT_FAILURE;
if (!all)
break;
}
if (f)
endmntent(f);
if (!all && f && m == NULL)
fprintf(stderr, "Can't find %s in /etc/fstab\n", device);
return rc;
}
goto singlemount;
}
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