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. 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  * @(#) Copyright (c) 1980, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)swapon.c 8.1 (Berkeley) 6/5/93
  31  * $FreeBSD: src/sbin/dumpon/dumpon.c,v 1.10.2.2 2001/07/30 10:30:05 dd Exp $
  32  * $DragonFly: src/sbin/dumpon/dumpon.c,v 1.5 2006/03/25 07:44:14 dillon Exp $
  33  */
  34
  35 #include <err.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40 #include <fstab.h>
  41 #include <sys/param.h>
  42 #include <sys/sysctl.h>
  43 #include <sys/stat.h>
  44 #include <sysexits.h>
  45
  46 void    usage(void) __dead2;
  47
  48 int
  49 main(int argc, char **argv)
  50 {
  51         int ch, verbose, rv;
  52         struct stat stab;
  53         int mib[2];
  54         char *path;
  55
  56         verbose = rv = 0;
  57         while ((ch = getopt(argc, argv, "v")) != -1) {
  58                 switch((char)ch) {
  59                 case 'v':
  60                         verbose = 1;
  61                         break;
  62                 case '?':
  63                 default:
  64                         usage();
  65                 }
  66         }
  67         argv += optind;
  68
  69         if (argv[0] == NULL || argv[1])
  70                 usage();
  71
  72         path = argv[0];
  73         if (strcmp(path, "off") == 0) {
  74                 stab.st_rdev = NODEV;
  75         } else {
  76                 path = getdevpath(path, 0);
  77                 rv = stat(path, &stab);
  78                 if (rv)
  79                         err(EX_OSFILE, "%s", path);
  80
  81                 if (!S_ISCHR(stab.st_mode)) {
  82                         errx(EX_USAGE,
  83                              "%s: must specify a character disk device",
  84                              path);
  85                 }
  86         }
  87
  88         mib[0] = CTL_KERN;
  89         mib[1] = KERN_DUMPDEV;
  90
  91         rv = sysctl(mib, 2, NULL, NULL, &stab.st_rdev, sizeof stab.st_rdev);
  92         if (rv) {
  93                 err(EX_OSERR, "sysctl: kern.dumpdev");
  94         }
  95
  96         if (verbose) {
  97                 if (stab.st_rdev == NODEV) {
  98                         printf("dumpon: crash dumps disabled\n");
  99                 } else {
 100                         printf("dumpon: crash dumps to %s (%lu, %#lx)\n",
 101                                path,
 102                                (unsigned long)major(stab.st_rdev),
 103                                (unsigned long)minor(stab.st_rdev));
 104                 }
 105         }
 106
 107         return 0;
 108 }
 109
 110 void
 111 usage(void)
 112 {
 113         fprintf(stderr,
 114                 "usage: dumpon [-v] special_file\n"
 115                 "       dumpon [-v] off\n");
 116         exit(EX_USAGE);
 117 }