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. 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, 1986, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)reboot.c 8.1 (Berkeley) 6/5/93
  31  * $FreeBSD: src/sbin/reboot/reboot.c,v 1.9.2.4 2002/04/28 22:50:00 wes Exp $
  32  */
  33
  34 #include <sys/reboot.h>
  35 #include <sys/types.h>
  36 #include <sys/sysctl.h>
  37 #include <signal.h>
  38 #include <err.h>
  39 #include <errno.h>
  40 #include <fcntl.h>
  41 #include <libutil.h>
  42 #include <pwd.h>
  43 #include <syslog.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48
  49 void usage(void);
  50 u_int get_pageins(void);
  51
  52 int dohalt;
  53
  54 int
  55 main(int argc, char *argv[])
  56 {
  57         struct passwd *pw;
  58         int ch, howto, i, fd, kflag, lflag, nflag, qflag, sverrno;
  59         u_int pageins;
  60         char *kernel = NULL, *p;
  61         const char *user;
  62
  63         if (strstr((p = strrchr(*argv, '/')) ? p + 1 : *argv, "halt")) {
  64                 dohalt = 1;
  65                 howto = RB_HALT;
  66         } else
  67                 howto = 0;
  68         kflag = lflag = nflag = qflag = 0;
  69         while ((ch = getopt(argc, argv, "dk:lnpq")) != -1)
  70                 switch(ch) {
  71                 case 'd':
  72                         howto |= RB_DUMP;
  73                         break;
  74                 case 'k':
  75                         kflag = 1;
  76                         kernel = optarg;
  77                         break;
  78                 case 'l':
  79                         lflag = 1;
  80                         break;
  81                 case 'n':
  82                         nflag = 1;
  83                         howto |= RB_NOSYNC;
  84                         break;
  85                 case 'p':
  86                         howto |= (RB_POWEROFF | RB_HALT);
  87                         break;
  88                 case 'q':
  89                         qflag = 1;
  90                         break;
  91                 case '?':
  92                 default:
  93                         usage();
  94                 }
  95         argc -= optind;
  96         argv += optind;
  97
  98         if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
  99                 errx(1, "cannot dump (-d) when halting; must reboot instead");
 100         if (geteuid()) {
 101                 errno = EPERM;
 102                 err(1, NULL);
 103         }
 104
 105         if (qflag) {
 106                 reboot(howto);
 107                 err(1, NULL);
 108         }
 109
 110         if (kflag) {
 111                 fd = open("/boot/nextboot.conf",
 112                           O_WRONLY | O_CREAT | O_TRUNC, 0444);
 113                 if (fd != -1) {
 114                         write(fd, "kernel=\"", 8L);
 115                         write(fd, kernel, strlen(kernel));
 116                         write(fd, "\"\n", 2);
 117                         close(fd);
 118                 }
 119         }
 120
 121         /* Log the reboot. */
 122         if (!lflag)  {
 123                 if ((user = getlogin()) == NULL)
 124                         user = (pw = getpwuid(getuid())) ?
 125                             pw->pw_name : "???";
 126                 if (dohalt) {
 127                         openlog("halt", 0, LOG_AUTH | LOG_CONS);
 128                         syslog(LOG_CRIT, "halted by %s", user);
 129                 } else {
 130                         openlog("reboot", 0, LOG_AUTH | LOG_CONS);
 131                         syslog(LOG_CRIT, "rebooted by %s", user);
 132                 }
 133         }
 134         logwtmp("~", "shutdown", "");
 135
 136         /*
 137          * Do a sync early on, so disks start transfers while we're off
 138          * killing processes.  Don't worry about writes done before the
 139          * processes die, the reboot system call syncs the disks.
 140          */
 141         if (!nflag)
 142                 sync();
 143
 144         /* Just stop init -- if we fail, we'll restart it. */
 145         if (kill(1, SIGTSTP) == -1)
 146                 err(1, "SIGTSTP init");
 147
 148         /* Ignore the SIGHUP we get when our parent shell dies. */
 149         signal(SIGHUP, SIG_IGN);
 150         /* parent shell might also send a SIGTERM?  Best to ignore as well */
 151         signal(SIGTERM, SIG_IGN);
 152
 153         /* Send a SIGTERM first, a chance to save the buffers. */
 154         if (kill(-1, SIGTERM) == -1)
 155                 err(1, "SIGTERM processes");
 156
 157         /*
 158          * After the processes receive the signal, start the rest of the
 159          * buffers on their way.  Wait 5 seconds between the SIGTERM and
 160          * the SIGKILL to give everybody a chance. If there is a lot of
 161          * paging activity then wait longer, up to a maximum of approx
 162          * 60 seconds.
 163          */
 164         sleep(2);
 165         for (i = 0; i < 20; i++) {
 166                 pageins = get_pageins();
 167                 if (!nflag)
 168                         sync();
 169                 sleep(3);
 170                 if (get_pageins() == pageins)
 171                         break;
 172         }
 173
 174         for (i = 1;; ++i) {
 175                 if (kill(-1, SIGKILL) == -1) {
 176                         if (errno == ESRCH)
 177                                 break;
 178                         goto restart;
 179                 }
 180                 if (i > 5) {
 181                         fprintf(stderr,
 182                             "WARNING: some process(es) wouldn't die\n");
 183                         break;
 184                 }
 185                 sleep(2 * i);
 186         }
 187
 188         reboot(howto);
 189         /* FALLTHROUGH */
 190
 191 restart:
 192         sverrno = errno;
 193         errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
 194             strerror(sverrno));
 195         /* NOTREACHED */
 196 }
 197
 198 void
 199 usage(void)
 200 {
 201         fprintf(stderr, "usage: %s [-dnpq] [-k kernel]\n",
 202             dohalt ? "halt" : "reboot");
 203         exit(1);
 204 }
 205
 206 u_int
 207 get_pageins(void)
 208 {
 209         u_int pageins;
 210         size_t len;
 211
 212         len = sizeof(pageins);
 213         if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
 214             != 0) {
 215                 warnx("v_swappgsin");
 216                 return (0);
 217         }
 218         return pageins;
 219 }