/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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. 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 <sys/stat.h>
#include <sys/uio.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include "mntopts.h"
static void usage(void) __dead2;
static int
stat_realpath(const char *path, char *resolved, struct stat *sbp)
{
if (realpath(path, resolved) == NULL || stat(resolved, sbp) != 0)
return (1);
return (0);
}
int
main(int argc, char *argv[])
{
struct iovec *iov;
char *p, *val;
char mountpoint[MAXPATHLEN];
char target[MAXPATHLEN];
char errmsg[255];
int ch, iovlen;
char nullfs[] = "nullfs";
struct stat target_stat;
struct stat mountpoint_stat;
iov = NULL;
iovlen = 0;
errmsg[0] = '\0';
while ((ch = getopt(argc, argv, "o:")) != -1)
switch(ch) {
case 'o':
val = strdup("");
p = strchr(optarg, '=');
if (p != NULL) {
free(val);
*p = '\0';
val = p + 1;
}
build_iovec(&iov, &iovlen, optarg, val, (size_t)-1);
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 2)
usage();
/* resolve target and mountpoint with realpath(3) */
if (stat_realpath(argv[0], target, &target_stat) != 0)
err(EX_USAGE, "%s", target);
if (stat_realpath(argv[1], mountpoint, &mountpoint_stat) != 0)
err(EX_USAGE, "%s", mountpoint);
if (!S_ISDIR(target_stat.st_mode) && !S_ISREG(target_stat.st_mode))
errx(EX_USAGE, "%s: must be either a file or directory",
target);
if ((target_stat.st_mode & S_IFMT) !=
(mountpoint_stat.st_mode & S_IFMT))
errx(EX_USAGE,
"%s: must be same type as %s (file or directory)",
mountpoint, target);
build_iovec(&iov, &iovlen, "fstype", nullfs, (size_t)-1);
build_iovec(&iov, &iovlen, "fspath", mountpoint, (size_t)-1);
build_iovec(&iov, &iovlen, "target", target, (size_t)-1);
build_iovec(&iov, &iovlen, "errmsg", errmsg, sizeof(errmsg));
if (nmount(iov, iovlen, 0) < 0) {
if (errmsg[0] != 0)
err(1, "%s: %s", mountpoint, errmsg);
else
err(1, "%s", mountpoint);
}
exit(0);
}
static void
usage(void)
{
(void)fprintf(stderr,
"usage: mount_nullfs [-o options] target mount-point\n");
exit(1);
}
