dumpon.c revision 53958 
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 53958 1999-11-30 16:27:30Z ache $";
46#endif /* not lint */
47
48#include <err.h>
49#include <stdio.h>
50#include <unistd.h>
51#include <sys/param.h>
52#include <sys/types.h>
53#include <sys/sysctl.h>
54#include <sys/stat.h>
55#include <sysexits.h>
56
57void	usage __P((void)) __dead2;
58
59int
60main(int argc, char **argv)
61{
62	int ch, verbose, rv;
63	struct stat stab;
64	int mib[2];
65
66	verbose = rv = 0;
67	while ((ch = getopt(argc, argv, "v")) != -1)
68		switch((char)ch) {
69		case 'v':
70			verbose = 1;
71			break;
72		case '?':
73		default:
74			usage();
75		}
76	argv += optind;
77
78	if (!argv[0] || argv[1])
79		usage();
80
81	if (strcmp(argv[0], "off")) {
82		rv = stat(argv[0], &stab);
83		if (rv) {
84			err(EX_OSFILE, "%s", argv[0]);
85		}
86
87		if (!S_ISCHR(stab.st_mode) && !S_ISBLK(stab.st_mode)) {
88			errx(EX_USAGE, "%s: must specify a device",
89			     argv[0]);
90		}
91	} else {
92		stab.st_rdev = NODEV;
93	}
94
95	mib[0] = CTL_KERN;
96	mib[1] = KERN_DUMPDEV;
97
98	rv = sysctl(mib, 2, (void *)0, (size_t *)0, &stab.st_rdev,
99		    sizeof stab.st_rdev);
100	if (rv) {
101		err(EX_OSERR, "sysctl: kern.dumpdev");
102	}
103
104	if (verbose) {
105		if (stab.st_rdev == NODEV) {
106			printf("dumpon: crash dumps disabled\n");
107		} else {
108			printf("dumpon: crash dumps to %s (%lu, %lu)\n",
109			       argv[0],
110			       (unsigned long)major(stab.st_rdev),
111			       (unsigned long)minor(stab.st_rdev));
112		}
113	}
114
115	return 0;
116}
117
118void
119usage()
120{
121	fprintf(stderr,
122		"usage: dumpon [-v] special_file\n"
123		"       dumpon [-v] off\n");
124	exit(EX_USAGE);
125}
126