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 * 4. 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
30#if 0
31#ifndef lint
32static const char copyright[] =
33"@(#) Copyright (c) 1980, 1993\n\
34	The Regents of the University of California.  All rights reserved.\n";
35#endif /* not lint */
36
37#ifndef lint
38static char sccsid[] = "From: @(#)swapon.c	8.1 (Berkeley) 6/5/93";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD$");
43
44#include <sys/param.h>
45#include <sys/disk.h>
46#include <sys/sysctl.h>
47
48#include <err.h>
49#include <errno.h>
50#include <fcntl.h>
51#include <paths.h>
52#include <stdint.h>
53#include <stdio.h>
54#include <stdlib.h>
55#include <string.h>
56#include <sysexits.h>
57#include <unistd.h>
58
59static int	verbose;
60
61static void
62usage(void)
63{
64	fprintf(stderr, "%s\n%s\n%s\n",
65	    "usage: dumpon [-v] special_file",
66	    "       dumpon [-v] off",
67	    "       dumpon [-v] -l");
68	exit(EX_USAGE);
69}
70
71static void
72check_size(int fd, const char *fn)
73{
74	int name[] = { CTL_HW, HW_PHYSMEM };
75	size_t namelen = sizeof(name) / sizeof(*name);
76	unsigned long physmem;
77	size_t len;
78	off_t mediasize;
79	int minidump;
80
81	len = sizeof(minidump);
82	if (sysctlbyname("debug.minidump", &minidump, &len, NULL, 0) == 0 &&
83	    minidump == 1)
84		return;
85	len = sizeof(physmem);
86	if (sysctl(name, namelen, &physmem, &len, NULL, 0) != 0)
87		err(EX_OSERR, "can't get memory size");
88	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) != 0)
89		err(EX_OSERR, "%s: can't get size", fn);
90	if ((uintmax_t)mediasize < (uintmax_t)physmem) {
91		if (verbose)
92			printf("%s is smaller than physical memory\n", fn);
93		exit(EX_IOERR);
94	}
95}
96
97static void
98listdumpdev(void)
99{
100	char dumpdev[PATH_MAX];
101	size_t len;
102	const char *sysctlname = "kern.shutdown.dumpdevname";
103
104	len = sizeof(dumpdev);
105	if (sysctlbyname(sysctlname, &dumpdev, &len, NULL, 0) != 0) {
106		if (errno == ENOMEM) {
107			err(EX_OSERR, "Kernel returned too large of a buffer for '%s'\n",
108				sysctlname);
109		} else {
110			err(EX_OSERR, "Sysctl get '%s'\n", sysctlname);
111		}
112	}
113	if (verbose) {
114		printf("kernel dumps on ");
115	}
116	if (strlen(dumpdev) == 0) {
117		printf("%s\n", _PATH_DEVNULL);
118	} else {
119		printf("%s\n", dumpdev);
120	}
121}
122
123int
124main(int argc, char *argv[])
125{
126	int ch;
127	int i, fd;
128	u_int u;
129	int do_listdumpdev = 0;
130
131	while ((ch = getopt(argc, argv, "lv")) != -1)
132		switch((char)ch) {
133		case 'l':
134			do_listdumpdev = 1;
135			break;
136		case 'v':
137			verbose = 1;
138			break;
139		default:
140			usage();
141		}
142
143	argc -= optind;
144	argv += optind;
145
146	if (do_listdumpdev) {
147		listdumpdev();
148		exit(EX_OK);
149	}
150
151	if (argc != 1)
152		usage();
153
154	if (strcmp(argv[0], "off") != 0) {
155		fd = open(argv[0], O_RDONLY);
156		if (fd < 0)
157			err(EX_OSFILE, "%s", argv[0]);
158		check_size(fd, argv[0]);
159		u = 0;
160		i = ioctl(fd, DIOCSKERNELDUMP, &u);
161		u = 1;
162		i = ioctl(fd, DIOCSKERNELDUMP, &u);
163		if (i == 0 && verbose)
164			printf("kernel dumps on %s\n", argv[0]);
165	} else {
166		fd = open(_PATH_DEVNULL, O_RDONLY);
167		if (fd < 0)
168			err(EX_OSFILE, "%s", _PATH_DEVNULL);
169		u = 0;
170		i = ioctl(fd, DIOCSKERNELDUMP, &u);
171		if (i == 0 && verbose)
172			printf("kernel dumps disabled\n");
173	}
174	if (i < 0)
175		err(EX_OSERR, "ioctl(DIOCSKERNELDUMP)");
176
177	exit (0);
178}
179