1 /* $NetBSD: mount_null.c,v 1.21 2020/07/26 08:20:22 mlelstv Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software donated to Berkeley by
8 * Jan-Simon Pendry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 #ifndef lint
37 __COPYRIGHT("@(#) Copyright (c) 1992, 1993, 1994\
38 The Regents of the University of California. All rights reserved.");
39 #endif /* not lint */
40
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)mount_null.c 8.6 (Berkeley) 4/26/95";
44 #else
45 __RCSID("$NetBSD: mount_null.c,v 1.21 2020/07/26 08:20:22 mlelstv Exp $");
46 #endif
47 #endif /* not lint */
48
49 #include <sys/param.h>
50 #include <sys/mount.h>
51 #include <miscfs/nullfs/null.h>
52
53 #include <err.h>
54 #include <stdio.h>
55 #include <unistd.h>
56 #include <stdlib.h>
57 #include <string.h>
58
59 #include <mntopts.h>
60
61 #include "mountprog.h"
62
63 static const struct mntopt mopts[] = {
64 MOPT_STDOPTS,
65 MOPT_GETARGS,
66 MOPT_NULL,
67 };
68
69 int mount_null(int argc, char **argv);
70 __dead static void usage(void);
71
72 #ifndef MOUNT_NOMAIN
73 int
main(int argc,char ** argv)74 main(int argc, char **argv)
75 {
76 return mount_null(argc, argv);
77 }
78 #endif
79
80 int
mount_null(int argc,char * argv[])81 mount_null(int argc, char *argv[])
82 {
83 struct null_args args;
84 int ch, mntflags;
85 char target[MAXPATHLEN], canon_dir[MAXPATHLEN];
86 mntoptparse_t mp;
87
88 mntflags = 0;
89 while ((ch = getopt(argc, argv, "o:")) != -1)
90 switch(ch) {
91 case 'o':
92 mp = getmntopts(optarg, mopts, &mntflags, 0);
93 if (mp == NULL)
94 err(1, "getmntopts");
95 freemntopts(mp);
96 break;
97 case '?':
98 default:
99 usage();
100 }
101 argc -= optind;
102 argv += optind;
103
104 if (argc != 2)
105 usage();
106
107 pathadj(argv[0], target);
108 pathadj(argv[1], canon_dir);
109
110 if (strcmp(target, canon_dir) == 0)
111 errx(1, "%s (%s) and %s (%s) are identical paths",
112 argv[0], target, argv[1], canon_dir);
113
114 args.la.target = target;
115
116 if (mount(MOUNT_NULL, canon_dir, mntflags, &args, sizeof args) == -1)
117 err(1, "%s on %s", target, canon_dir);
118 exit(0);
119 }
120
121 static void
usage(void)122 usage(void)
123 {
124 (void)fprintf(stderr,
125 "usage: mount_null [-o options] target_fs mount_point\n");
126 exit(1);
127 }
128