sysvinit/src/mountpoint.c

129 lines
2.8 KiB
C

/*
* mountpoint See if a directory is a mountpoint.
*
* Author: Miquel van Smoorenburg.
*
* Version: @(#)mountpoint 2.85-12 17-Mar-2004 miquels@cistron.nl
*
* This file is part of the sysvinit suite,
* Copyright (C) 1991-2004 Miquel van Smoorenburg.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include <getopt.h>
#include <stdio.h>
int dostat(char *path, struct stat *st, int do_lstat, int quiet)
{
int n;
if (do_lstat)
n = lstat(path, st);
else
n = stat(path, st);
if (n != 0) {
if (!quiet)
fprintf(stderr, "mountpoint: %s: %s\n", path,
strerror(errno));
return -1;
}
return 0;
}
void usage(void) {
fprintf(stderr, "Usage: mountpoint [-q] [-d] [-x] path\n");
exit(1);
}
int main(int argc, char **argv)
{
struct stat st, st2;
char buf[256];
char *path;
int quiet = 0;
int showdev = 0;
int xdev = 0;
int c, r;
while ((c = getopt(argc, argv, "dqx")) != EOF) switch(c) {
case 'd':
showdev = 1;
break;
case 'q':
quiet = 1;
break;
case 'x':
xdev = 1;
break;
default:
usage();
break;
}
if (optind != argc - 1) usage();
path = argv[optind];
if (dostat(path, &st, !xdev, quiet) < 0)
return 1;
if (xdev) {
#ifdef __linux__
if (!S_ISBLK(st.st_mode))
#else
if (!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode))
#endif
{
if (quiet)
printf("\n");
else
fprintf(stderr, "mountpoint: %s: not a block device\n",
path);
return 1;
}
printf("%u:%u\n", major(st.st_rdev), minor(st.st_rdev));
return 0;
}
if (!S_ISDIR(st.st_mode)) {
if (!quiet)
fprintf(stderr, "mountpoint: %s: not a directory\n",
path);
return 1;
}
memset(buf, 0, sizeof(buf));
strncpy(buf, path, sizeof(buf) - 4);
strcat(buf, "/..");
if (dostat(buf, &st2, 0, quiet) < 0)
return 1;
r = (st.st_dev != st2.st_dev) ||
(st.st_dev == st2.st_dev && st.st_ino == st2.st_ino);
if (!quiet && !showdev)
printf("%s is %sa mountpoint\n", path, r ? "" : "not ");
if (showdev)
printf("%u:%u\n", major(st.st_dev), minor(st.st_dev));
return r ? 0 : 1;
}