ubase/mount.c
2014-06-30 19:04:47 +01:00

240 lines
5.1 KiB
C

/* See LICENSE file for copyright and license details. */
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <limits.h>
#include <mntent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "util.h"
struct {
const char *opt;
const char *notopt;
unsigned long v;
} optnames[] = {
{ "defaults", NULL, 0 },
{ "remount", NULL, MS_REMOUNT },
{ "ro", "rw", MS_RDONLY },
{ "sync", "async", MS_SYNCHRONOUS },
{ "dirsync", NULL, MS_DIRSYNC },
{ "nodev", "dev", MS_NODEV },
{ "noatime", "atime", MS_NOATIME },
{ "nodiratime", "diratime", MS_NODIRATIME },
{ "noexec", "exec", MS_NOEXEC },
{ "nosuid", "suid", MS_NOSUID },
{ "mand", "nomand", MS_MANDLOCK },
{ "relatime", "norelatime", MS_RELATIME },
{ "bind", NULL, MS_BIND },
{ NULL, NULL, 0 }
};
static void
parseopts(char *popts, unsigned long *flags, char *data, size_t datasiz)
{
unsigned int i, validopt;
size_t optlen, dlen = 0;
char *name;
data[0] = '\0';
for(name = strtok(popts, ","); name; name = strtok(NULL, ",")) {
validopt = 0;
for(i = 0; optnames[i].opt; i++) {
if(optnames[i].opt && strcmp(name, optnames[i].opt) == 0) {
*flags |= optnames[i].v;
validopt = 1;
break;
}
if(optnames[i].notopt && strcmp(name, optnames[i].notopt) == 0) {
*flags &= ~optnames[i].v;
validopt = 1;
break;
}
}
if(!validopt) {
/* unknown option, pass as data option to mount() */
if((optlen = strlen(name))) {
if(dlen + optlen + 2 >= datasiz)
return; /* prevent overflow */
if(dlen)
data[dlen++] = ',';
memcpy(&data[dlen], name, optlen);
dlen += optlen;
data[dlen] = '\0';
}
}
}
}
static int
mounted(const char *dir)
{
FILE *fp;
struct mntent *me;
struct stat st1, st2;
if (stat(dir, &st1) < 0) {
weprintf("stat %s:", dir);
return 0;
}
fp = setmntent("/proc/mounts", "r");
if (!fp)
eprintf("setmntent %s:", "/proc/mounts");
while ((me = getmntent(fp)) != NULL) {
if (stat(me->mnt_dir, &st2) < 0) {
weprintf("stat %s:", me->mnt_dir);
continue;
}
if (st1.st_dev == st2.st_dev &&
st1.st_ino == st2.st_ino)
return 1;
}
endmntent(fp);
return 0;
}
static void
usage(void)
{
eprintf("usage: %s [-BMRan] [-t fstype] [-o options] [source] [target]\n",
argv0);
}
static int
catfile(FILE *in, FILE *out)
{
char buf[BUFSIZ];
size_t bytesread;
while(!feof(in)) {
bytesread = fread(buf, 1, sizeof(buf), in);
if(ferror(in))
return 0;
fwrite(buf, 1, bytesread, out);
}
return 1;
}
int
main(int argc, char *argv[])
{
int aflag = 0, oflag = 0, status = EXIT_SUCCESS, i;
unsigned long flags = 0;
char *types = NULL, data[512] = "", *resolvpath = NULL;
char *files[] = { "/proc/mounts", "/etc/fstab", NULL };
size_t datasiz = sizeof(data);
const char *source, *target;
struct mntent *me = NULL;
FILE *fp;
ARGBEGIN {
case 'B':
flags |= MS_BIND;
break;
case 'M':
flags |= MS_MOVE;
break;
case 'R':
flags |= MS_REC;
break;
case 'a':
aflag = 1;
break;
case 'o':
oflag = 1;
parseopts(EARGF(usage()), &flags, data, datasiz);
break;
case 't':
types = EARGF(usage());
break;
case 'n':
break;
default:
usage();
} ARGEND;
if(argc < 1 && aflag == 0) {
if(!(fp = fopen(files[0], "r")))
eprintf("fopen %s:", files[0]);
if(catfile(fp, stdout) != 1) {
weprintf("error while reading %s:", files[0]);
status = EXIT_FAILURE;
}
fclose(fp);
return status;
}
if(aflag == 1)
goto mountall;
source = argv[0];
target = argv[1];
if(!target) {
target = argv[0];
source = NULL;
if(!(resolvpath = realpath(target, NULL)))
eprintf("realpath %s:", target);
target = resolvpath;
}
for(i = 0; files[i]; i++) {
if(!(fp = setmntent(files[i], "r"))) {
if (strcmp(files[i], "/proc/mounts") != 0)
weprintf("setmntent %s:", files[i]);
continue;
}
while((me = getmntent(fp))) {
if(strcmp(me->mnt_dir, target) == 0 ||
strcmp(me->mnt_fsname, target) == 0 ||
(source && strcmp(me->mnt_dir, source) == 0) ||
(source && strcmp(me->mnt_fsname, source) == 0)) {
if(!source) {
target = me->mnt_dir;
source = me->mnt_fsname;
}
if(!oflag)
parseopts(me->mnt_opts, &flags, data, datasiz);
if(!types)
types = me->mnt_type;
goto mountsingle;
}
}
endmntent(fp);
fp = NULL;
}
if(!source)
eprintf("can't find %s in /etc/fstab\n", target);
mountsingle:
if(mount(source, target, types, flags, data) < 0) {
weprintf("mount: %s:", source);
status = EXIT_FAILURE;
}
if(fp)
endmntent(fp);
free(resolvpath);
return status;
mountall:
if(!(fp = setmntent("/etc/fstab", "r")))
eprintf("setmntent %s:", "/etc/fstab");
while((me = getmntent(fp))) {
flags = 0;
parseopts(me->mnt_opts, &flags, data, datasiz);
if(mount(me->mnt_fsname, me->mnt_dir, me->mnt_type, flags, data) < 0) {
if(mounted(me->mnt_dir) == 0) {
weprintf("mount: %s:", me->mnt_fsname);
status = EXIT_FAILURE;
}
}
}
endmntent(fp);
return status;
}