202 lines
4.5 KiB
C
202 lines
4.5 KiB
C
/*
|
|
* mountpoint(1) - see if a directory is a mountpoint
|
|
*
|
|
* This is libmount based reimplementation of the mountpoit(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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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"
|
|
|
|
static int quiet;
|
|
|
|
static dev_t dir_to_device(const char *spec)
|
|
{
|
|
struct libmnt_table *tb = mnt_new_table_from_file("/proc/self/mountinfo");
|
|
struct libmnt_fs *fs;
|
|
struct libmnt_cache *cache;
|
|
dev_t res = 0;
|
|
|
|
if (!tb) {
|
|
/*
|
|
* Fallback. Traditional way to detect mountpoints. This way
|
|
* is independent on /proc, but not able to detect bind mounts.
|
|
*/
|
|
struct stat pst, st;
|
|
char buf[PATH_MAX], *cn;
|
|
int len;
|
|
|
|
if (stat(spec, &st) != 0)
|
|
return 0;
|
|
|
|
cn = mnt_resolve_path(spec, NULL); /* canonicalize */
|
|
|
|
len = snprintf(buf, sizeof(buf), "%s/..", cn ? cn : spec);
|
|
free(cn);
|
|
|
|
if (len < 0 || (size_t) len + 1 > sizeof(buf))
|
|
return 0;
|
|
if (stat(buf, &pst) !=0)
|
|
return 0;
|
|
|
|
if ((st.st_dev != pst.st_dev) ||
|
|
(st.st_dev == pst.st_dev && st.st_ino == pst.st_ino))
|
|
return st.st_dev;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* to canonicalize all necessary paths */
|
|
cache = mnt_new_cache();
|
|
mnt_table_set_cache(tb, cache);
|
|
|
|
fs = mnt_table_find_target(tb, spec, MNT_ITER_BACKWARD);
|
|
if (fs && mnt_fs_get_target(fs))
|
|
res = mnt_fs_get_devno(fs);
|
|
|
|
mnt_free_table(tb);
|
|
mnt_free_cache(cache);
|
|
return res;
|
|
}
|
|
|
|
static int print_devno(const char *devname, struct stat *st)
|
|
{
|
|
struct stat stbuf;
|
|
|
|
if (!st && stat(devname, &stbuf) == 0)
|
|
st = &stbuf;
|
|
if (!st)
|
|
return -1;
|
|
if (!S_ISBLK(st->st_mode)) {
|
|
if (!quiet)
|
|
warnx(_("%s: not a block device"), devname);
|
|
return -1;
|
|
}
|
|
printf("%u:%u\n", major(st->st_rdev), minor(st->st_rdev));
|
|
return 0;
|
|
}
|
|
|
|
static void __attribute__((__noreturn__)) usage(FILE *out)
|
|
{
|
|
fputs(_("\nUsage:\n"), out);
|
|
fprintf(out,
|
|
_(" %1$s [-qd] /path/to/directory\n"
|
|
" %1$s -x /dev/device\n"), program_invocation_short_name);
|
|
|
|
fputs(_("\nOptions:\n"), 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"
|
|
" -h, --help this help\n"), out);
|
|
|
|
fprintf(out, _("\nFor more information see mountpoint(1).\n"));
|
|
|
|
exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
int c, fs_devno = 0, dev_devno = 0, rc = 0;
|
|
char *spec;
|
|
struct stat st;
|
|
|
|
static const struct option longopts[] = {
|
|
{ "quiet", 0, 0, 'q' },
|
|
{ "fs-devno", 0, 0, 'd' },
|
|
{ "devno", 0, 0, 'x' },
|
|
{ "help", 0, 0, 'h' },
|
|
{ NULL, 0, 0, 0 }
|
|
};
|
|
|
|
setlocale(LC_ALL, "");
|
|
bindtextdomain(PACKAGE, LOCALEDIR);
|
|
textdomain(PACKAGE);
|
|
|
|
mnt_init_debug(0);
|
|
|
|
while ((c = getopt_long(argc, argv, "qdxh", longopts, NULL)) != -1) {
|
|
|
|
switch(c) {
|
|
case 'q':
|
|
quiet = 1;
|
|
break;
|
|
case 'd':
|
|
fs_devno = 1;
|
|
break;
|
|
case 'x':
|
|
dev_devno = 1;
|
|
break;
|
|
case 'h':
|
|
usage(stdout);
|
|
break;
|
|
default:
|
|
usage(stderr);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (optind + 1 != argc)
|
|
usage(stderr);
|
|
|
|
spec = argv[optind++];
|
|
|
|
if (stat(spec, &st)) {
|
|
if (!quiet)
|
|
err(EXIT_FAILURE, "%s", spec);
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (dev_devno)
|
|
rc = print_devno(spec, &st);
|
|
else {
|
|
dev_t src;
|
|
|
|
if (!S_ISDIR(st.st_mode)) {
|
|
if (!quiet)
|
|
errx(EXIT_FAILURE, _("%s: not a directory"), spec);
|
|
return EXIT_FAILURE;
|
|
}
|
|
src = dir_to_device(spec);
|
|
if (!src) {
|
|
if (!quiet)
|
|
printf(_("%s is not a mountpoint\n"), spec);
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (fs_devno)
|
|
printf("%u:%u\n", major(src), minor(src));
|
|
else if (!quiet)
|
|
printf(_("%s is a mountpoint\n"), spec);
|
|
}
|
|
|
|
return rc ? EXIT_FAILURE : EXIT_SUCCESS;
|
|
}
|