dumpon.c revision 92542 
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. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1980, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "From: @(#)swapon.c	8.1 (Berkeley) 6/5/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/sbin/dumpon/dumpon.c 92542 2002-03-18 06:59:15Z imp $";
46#endif /* not lint */
47
48#include <err.h>
49#include <stdio.h>
50#include <stdlib.h>
51#include <string.h>
52#include <unistd.h>
53#include <sys/param.h>
54#include <sys/sysctl.h>
55#include <sys/stat.h>
56#include <sysexits.h>
57
58void	usage(void) __dead2;
59
60int
61main(int argc, char *argv[])
62{
63	int ch, verbose, rv;
64	struct stat stab;
65	int mib[2];
66
67	verbose = rv = 0;
68	while ((ch = getopt(argc, argv, "v")) != -1)
69		switch((char)ch) {
70		case 'v':
71			verbose = 1;
72			break;
73		case '?':
74		default:
75			usage();
76		}
77	argv += optind;
78
79	if (!argv[0] || argv[1])
80		usage();
81
82	if (strcmp(argv[0], "off")) {
83		rv = stat(argv[0], &stab);
84		if (rv) {
85			err(EX_OSFILE, "%s", argv[0]);
86		}
87
88		if (!S_ISCHR(stab.st_mode)) {
89			errx(EX_USAGE,
90			     "%s: must specify a character disk device",
91			     argv[0]);
92		}
93	} else {
94		stab.st_rdev = NODEV;
95	}
96
97	mib[0] = CTL_KERN;
98	mib[1] = KERN_DUMPDEV;
99
100	rv = sysctl(mib, 2, (void *)0, (size_t *)0, &stab.st_rdev,
101		    sizeof stab.st_rdev);
102	if (rv) {
103		err(EX_OSERR, "sysctl: kern.dumpdev");
104	}
105
106	if (verbose) {
107		if (stab.st_rdev == NODEV) {
108			printf("dumpon: crash dumps disabled\n");
109		} else {
110			printf("dumpon: crash dumps to %s (%lu, %lu)\n",
111			       argv[0],
112			       (unsigned long)major(stab.st_rdev),
113			       (unsigned long)minor(stab.st_rdev));
114		}
115	}
116
117	return (0);
118}
119
120void
121usage(void)
122{
123	fprintf(stderr,
124		"usage: dumpon [-v] special_file\n"
125		"       dumpon [-v] off\n");
126	exit(EX_USAGE);
127}
128