sbin/reboot/reboot.c

   1 /*
   2  * Copyright (c) 1980, 1986, 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, 1986, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)reboot.c 8.1 (Berkeley) 6/5/93
  35  * $FreeBSD: src/sbin/reboot/reboot.c,v 1.9.2.4 2002/04/28 22:50:00 wes Exp $
  36  * $DragonFly: src/sbin/reboot/reboot.c,v 1.7 2005/03/21 17:57:54 joerg Exp $
  37  */
  38
  39 #include <sys/reboot.h>
  40 #include <sys/types.h>
  41 #include <sys/sysctl.h>
  42 #include <signal.h>
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <fcntl.h>
  46 #include <libutil.h>
  47 #include <pwd.h>
  48 #include <syslog.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53
  54 void usage(void);
  55 u_int get_pageins(void);
  56
  57 int dohalt;
  58
  59 int
  60 main(int argc, char *argv[])
  61 {
  62         struct passwd *pw;
  63         int ch, howto, i, fd, kflag, lflag, nflag, qflag, pflag, sverrno;
  64         u_int pageins;
  65         char *kernel = NULL, *p;
  66         const char *user;
  67
  68         if (strstr((p = strrchr(*argv, '/')) ? p + 1 : *argv, "halt")) {
  69                 dohalt = 1;
  70                 howto = RB_HALT;
  71         } else
  72                 howto = 0;
  73         kflag = lflag = nflag = qflag = 0;
  74         while ((ch = getopt(argc, argv, "dk:lnpq")) != -1)
  75                 switch(ch) {
  76                 case 'd':
  77                         howto |= RB_DUMP;
  78                         break;
  79                 case 'k':
  80                         kflag = 1;
  81                         kernel = optarg;
  82                         break;
  83                 case 'l':
  84                         lflag = 1;
  85                         break;
  86                 case 'n':
  87                         nflag = 1;
  88                         howto |= RB_NOSYNC;
  89                         break;
  90                 case 'p':
  91                         pflag = 1;
  92                         howto |= (RB_POWEROFF | RB_HALT);
  93                         break;
  94                 case 'q':
  95                         qflag = 1;
  96                         break;
  97                 case '?':
  98                 default:
  99                         usage();
 100                 }
 101         argc -= optind;
 102         argv += optind;
 103
 104         if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
 105                 errx(1, "cannot dump (-d) when halting; must reboot instead");
 106         if (geteuid()) {
 107                 errno = EPERM;
 108                 err(1, NULL);
 109         }
 110
 111         if (qflag) {
 112                 reboot(howto);
 113                 err(1, NULL);
 114         }
 115
 116         if (kflag) {
 117                 fd = open("/boot/nextboot.conf",
 118                           O_WRONLY | O_CREAT | O_TRUNC, 0444);
 119                 if (fd != -1) {
 120                         write(fd, "kernel=\"", 8L);
 121                         write(fd, kernel, strlen(kernel));
 122                         write(fd, "\"\n", 2);
 123                         close(fd);
 124                 }
 125         }
 126
 127         /* Log the reboot. */
 128         if (!lflag)  {
 129                 if ((user = getlogin()) == NULL)
 130                         user = (pw = getpwuid(getuid())) ?
 131                             pw->pw_name : "???";
 132                 if (dohalt) {
 133                         openlog("halt", 0, LOG_AUTH | LOG_CONS);
 134                         syslog(LOG_CRIT, "halted by %s", user);
 135                 } else {
 136                         openlog("reboot", 0, LOG_AUTH | LOG_CONS);
 137                         syslog(LOG_CRIT, "rebooted by %s", user);
 138                 }
 139         }
 140         logwtmp("~", "shutdown", "");
 141
 142         /*
 143          * Do a sync early on, so disks start transfers while we're off
 144          * killing processes.  Don't worry about writes done before the
 145          * processes die, the reboot system call syncs the disks.
 146          */
 147         if (!nflag)
 148                 sync();
 149
 150         /* Just stop init -- if we fail, we'll restart it. */
 151         if (kill(1, SIGTSTP) == -1)
 152                 err(1, "SIGTSTP init");
 153
 154         /* Ignore the SIGHUP we get when our parent shell dies. */
 155         signal(SIGHUP, SIG_IGN);
 156
 157         /* Send a SIGTERM first, a chance to save the buffers. */
 158         if (kill(-1, SIGTERM) == -1)
 159                 err(1, "SIGTERM processes");
 160
 161         /*
 162          * After the processes receive the signal, start the rest of the
 163          * buffers on their way.  Wait 5 seconds between the SIGTERM and
 164          * the SIGKILL to give everybody a chance. If there is a lot of
 165          * paging activity then wait longer, up to a maximum of approx
 166          * 60 seconds.
 167          */
 168         sleep(2);
 169         for (i = 0; i < 20; i++) {
 170                 pageins = get_pageins();
 171                 if (!nflag)
 172                         sync();
 173                 sleep(3);
 174                 if (get_pageins() == pageins)
 175                         break;
 176         }
 177
 178         for (i = 1;; ++i) {
 179                 if (kill(-1, SIGKILL) == -1) {
 180                         if (errno == ESRCH)
 181                                 break;
 182                         goto restart;
 183                 }
 184                 if (i > 5) {
 185                         fprintf(stderr,
 186                             "WARNING: some process(es) wouldn't die\n");
 187                         break;
 188                 }
 189                 sleep(2 * i);
 190         }
 191
 192         reboot(howto);
 193         /* FALLTHROUGH */
 194
 195 restart:
 196         sverrno = errno;
 197         errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
 198             strerror(sverrno));
 199         /* NOTREACHED */
 200 }
 201
 202 void
 203 usage(void)
 204 {
 205         fprintf(stderr, "usage: %s [-dnpq] [-k kernel]\n",
 206             dohalt ? "halt" : "reboot");
 207         exit(1);
 208 }
 209
 210 u_int
 211 get_pageins(void)
 212 {
 213         u_int pageins;
 214         size_t len;
 215
 216         len = sizeof(pageins);
 217         if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
 218             != 0) {
 219                 warnx("v_swappgsin");
 220                 return (0);
 221         }
 222         return pageins;
 223 }