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/*
* Copyright (c) 1992, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software donated to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1992, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)mount_null.c 8.6 (Berkeley) 4/26/95";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/mount.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include "mntopts.h"
struct mntopt mopts[] = {
MOPT_STDOPTS,
{ NULL }
};
int subdir(const char *, const char *);
static void usage(void) __dead2;
int
main(argc, argv)
int argc;
char *argv[];
{
struct iovec iov[6];
int ch, mntflags;
char source[MAXPATHLEN];
char target[MAXPATHLEN];
int error;
mntflags = 0;
while ((ch = getopt(argc, argv, "o:")) != -1)
switch(ch) {
case 'o':
getmntopts(optarg, mopts, &mntflags, 0);
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 2)
usage();
/* resolve target and source with realpath(3) */
(void)checkpath(argv[0], target);
(void)checkpath(argv[1], source);
if (subdir(target, source) || subdir(source, target))
errx(EX_USAGE, "%s (%s) and %s are not distinct paths",
argv[0], target, argv[1]);
iov[0].iov_base = "fstype";
iov[0].iov_len = sizeof("fstype");
iov[1].iov_base = "nullfs";
iov[1].iov_len = strlen("nullfs") + 1;
iov[2].iov_base = "fspath";
iov[2].iov_len = sizeof("fspath");
iov[3].iov_base = source;
iov[3].iov_len = strlen(source) + 1;
iov[4].iov_base = "target";
iov[4].iov_len = sizeof("target");
iov[5].iov_base = target;
iov[5].iov_len = strlen(target) + 1;
if (nmount(iov, 6, mntflags))
err(1, NULL);
exit(0);
}
int
subdir(p, dir)
const char *p;
const char *dir;
{
int l;
l = strlen(dir);
if (l <= 1)
return (1);
if ((strncmp(p, dir, l) == 0) && (p[l] == '/' || p[l] == '\0'))
return (1);
return (0);
}
static void
usage()
{
(void)fprintf(stderr,
"usage: mount_nullfs [-o options] target_fs mount_point\n");
exit(1);
}
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