sbin/dumpon/dumpon.c

   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  * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)swapon.c 8.1 (Berkeley) 6/5/93
  35  * $FreeBSD: src/sbin/dumpon/dumpon.c,v 1.10.2.2 2001/07/30 10:30:05 dd Exp $
  36  * $DragonFly: src/sbin/dumpon/dumpon.c,v 1.5 2006/03/25 07:44:14 dillon Exp $
  37  */
  38
  39 #include <err.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44 #include <fstab.h>
  45 #include <sys/param.h>
  46 #include <sys/sysctl.h>
  47 #include <sys/stat.h>
  48 #include <sysexits.h>
  49
  50 void    usage(void) __dead2;
  51
  52 int
  53 main(int argc, char **argv)
  54 {
  55         int ch, verbose, rv;
  56         struct stat stab;
  57         int mib[2];
  58         char *path;
  59
  60         verbose = rv = 0;
  61         while ((ch = getopt(argc, argv, "v")) != -1) {
  62                 switch((char)ch) {
  63                 case 'v':
  64                         verbose = 1;
  65                         break;
  66                 case '?':
  67                 default:
  68                         usage();
  69                 }
  70         }
  71         argv += optind;
  72
  73         if (argv[0] == NULL || argv[1])
  74                 usage();
  75
  76         path = argv[0];
  77         if (strcmp(path, "off") == 0) {
  78                 stab.st_rdev = NODEV;
  79         } else {
  80                 path = getdevpath(path, 0);
  81                 rv = stat(path, &stab);
  82                 if (rv)
  83                         err(EX_OSFILE, "%s", path);
  84
  85                 if (!S_ISCHR(stab.st_mode)) {
  86                         errx(EX_USAGE,
  87                              "%s: must specify a character disk device",
  88                              path);
  89                 }
  90         }
  91
  92         mib[0] = CTL_KERN;
  93         mib[1] = KERN_DUMPDEV;
  94
  95         rv = sysctl(mib, 2, NULL, NULL, &stab.st_rdev, sizeof stab.st_rdev);
  96         if (rv) {
  97                 err(EX_OSERR, "sysctl: kern.dumpdev");
  98         }
  99
 100         if (verbose) {
 101                 if (stab.st_rdev == NODEV) {
 102                         printf("dumpon: crash dumps disabled\n");
 103                 } else {
 104                         printf("dumpon: crash dumps to %s (%lu, %#lx)\n",
 105                                path,
 106                                (unsigned long)major(stab.st_rdev),
 107                                (unsigned long)minor(stab.st_rdev));
 108                 }
 109         }
 110
 111         return 0;
 112 }
 113
 114 void
 115 usage(void)
 116 {
 117         fprintf(stderr,
 118                 "usage: dumpon [-v] special_file\n"
 119                 "       dumpon [-v] off\n");
 120         exit(EX_USAGE);
 121 }