1 /*
2 * Copyright (c) 1980, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)swapon.c 8.1 (Berkeley) 6/5/93
30 * $FreeBSD: src/sbin/dumpon/dumpon.c,v 1.10.2.2 2001/07/30 10:30:05 dd Exp $
31 */
32
33 #include <err.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <stdbool.h>
37 #include <string.h>
38 #include <unistd.h>
39 #include <fstab.h>
40 #include <sys/param.h>
41 #include <sys/sysctl.h>
42 #include <sys/stat.h>
43 #include <sysexits.h>
44
45 static const char *sc_name = "kern.dumpdev";
46
47 static struct stat *get_dumpdev(void);
48 static void usage(void) __dead2;
49
50 int
main(int argc,char ** argv)51 main(int argc, char **argv)
52 {
53 int ch;
54 struct stat stab;
55 struct stat *stab_old;
56 char *path, *p;
57 bool is_dumpoff;
58
59 if (strstr((p = strrchr(argv[0], '/')) ? p+1 : argv[0],
60 "dumpoff") != 0) {
61 is_dumpoff = true;
62 } else {
63 is_dumpoff = false;
64 }
65
66 while ((ch = getopt(argc, argv, "v")) != -1) {
67 switch (ch) {
68 case 'v':
69 /* backward compatibility only */
70 break;
71 case '?':
72 default:
73 usage();
74 }
75 }
76 argc -= optind;
77 argv += optind;
78
79 if ((is_dumpoff && argc != 0) || (!is_dumpoff && argc != 1))
80 usage();
81
82 path = argv[0];
83 if (is_dumpoff || strcmp(path, "off") == 0) {
84 stab.st_rdev = NODEV;
85 } else {
86 path = getdevpath(path, 0);
87 if (stat(path, &stab) != 0)
88 err(EX_OSFILE, "%s", path);
89
90 if (!S_ISCHR(stab.st_mode)) {
91 errx(EX_USAGE,
92 "%s: must specify a character disk device",
93 path);
94 }
95 }
96
97 stab_old = get_dumpdev();
98
99 if (stab.st_rdev == stab_old->st_rdev) {
100 if (stab.st_rdev == NODEV) {
101 printf("dumpon: crash dumps already disabled.\n");
102 } else {
103 printf("dumpon: crash dumps already configured "
104 "to the given device.\n");
105 }
106 } else if (stab.st_rdev == NODEV || stab_old->st_rdev == NODEV) {
107 if (sysctlbyname(sc_name, NULL, NULL,
108 &stab.st_rdev, sizeof stab.st_rdev) != 0) {
109 err(EX_OSERR, "sysctl: %s", sc_name);
110 }
111 if (stab.st_rdev == NODEV) {
112 printf("dumpon: crash dumps disabled\n");
113 } else {
114 printf("dumpon: crash dumps to %s (%lu, %#lx)\n",
115 path,
116 (unsigned long)major(stab.st_rdev),
117 (unsigned long)minor(stab.st_rdev));
118 }
119 } else {
120 warnx("crash dumps already configured "
121 "to another device (%lu, %#lx)",
122 (unsigned long)major(stab.st_rdev),
123 (unsigned long)minor(stab.st_rdev));
124 errx(EX_USAGE, "you need to run 'dumpoff' first.");
125 }
126
127 return 0;
128 }
129
130
131 static struct stat *
get_dumpdev(void)132 get_dumpdev(void)
133 {
134 struct stat *stab;
135 size_t len;
136
137 if ((stab = malloc(sizeof(*stab))) == NULL)
138 err(EX_OSERR, "malloc");
139
140 memset(stab, 0, sizeof(*stab));
141 len = sizeof(stab->st_rdev);
142 if (sysctlbyname(sc_name, &stab->st_rdev, &len, NULL, 0) != 0)
143 err(EX_OSERR, "sysctl: %s", sc_name);
144
145 return stab;
146 }
147
148 static void
usage(void)149 usage(void)
150 {
151 fprintf(stderr,
152 "usage: dumpon [-v] special_file\n"
153 " dumpon [-v] off\n"
154 " dumpoff [-v]\n");
155 exit(EX_USAGE);
156 }
157