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 1.3 2003/09/28 14:39:21 hmp 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, *p;
  66         const char *user;
  67
  68         if (strstr((p = rindex(*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", O_WRONLY | O_CREAT, 0444);
 118                 if (fd > -1) {
 119                         (void)write(fd, "kernel=\"", 8L);
 120                         (void)write(fd, kernel, strlen(kernel));
 121                         (void)write(fd, "\"\n", 2);
 122                         close(fd);
 123                 }
 124         }
 125
 126         /* Log the reboot. */
 127         if (!lflag)  {
 128                 if ((user = getlogin()) == NULL)
 129                         user = (pw = getpwuid(getuid())) ?
 130                             pw->pw_name : "???";
 131                 if (dohalt) {
 132                         openlog("halt", 0, LOG_AUTH | LOG_CONS);
 133                         syslog(LOG_CRIT, "halted by %s", user);
 134                 } else {
 135                         openlog("reboot", 0, LOG_AUTH | LOG_CONS);
 136                         syslog(LOG_CRIT, "rebooted by %s", user);
 137                 }
 138         }
 139         logwtmp("~", "shutdown", "");
 140
 141         /*
 142          * Do a sync early on, so disks start transfers while we're off
 143          * killing processes.  Don't worry about writes done before the
 144          * processes die, the reboot system call syncs the disks.
 145          */
 146         if (!nflag)
 147                 sync();
 148
 149         /* Just stop init -- if we fail, we'll restart it. */
 150         if (kill(1, SIGTSTP) == -1)
 151                 err(1, "SIGTSTP init");
 152
 153         /* Ignore the SIGHUP we get when our parent shell dies. */
 154         (void)signal(SIGHUP, SIG_IGN);
 155
 156         /* Send a SIGTERM first, a chance to save the buffers. */
 157         if (kill(-1, SIGTERM) == -1)
 158                 err(1, "SIGTERM processes");
 159
 160         /*
 161          * After the processes receive the signal, start the rest of the
 162          * buffers on their way.  Wait 5 seconds between the SIGTERM and
 163          * the SIGKILL to give everybody a chance. If there is a lot of
 164          * paging activity then wait longer, up to a maximum of approx
 165          * 60 seconds.
 166          */
 167         sleep(2);
 168         for (i = 0; i < 20; i++) {
 169                 pageins = get_pageins();
 170                 if (!nflag)
 171                         sync();
 172                 sleep(3);
 173                 if (get_pageins() == pageins)
 174                         break;
 175         }
 176
 177         for (i = 1;; ++i) {
 178                 if (kill(-1, SIGKILL) == -1) {
 179                         if (errno == ESRCH)
 180                                 break;
 181                         goto restart;
 182                 }
 183                 if (i > 5) {
 184                         (void)fprintf(stderr,
 185                             "WARNING: some process(es) wouldn't die\n");
 186                         break;
 187                 }
 188                 (void)sleep(2 * i);
 189         }
 190
 191         reboot(howto);
 192         /* FALLTHROUGH */
 193
 194 restart:
 195         sverrno = errno;
 196         errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
 197             strerror(sverrno));
 198         /* NOTREACHED */
 199 }
 200
 201 void
 202 usage(void)
 203 {
 204         (void)fprintf(stderr, "usage: %s [-dnpq] [-k kernel]\n",
 205             dohalt ? "halt" : "reboot");
 206         exit(1);
 207 }
 208
 209 u_int
 210 get_pageins(void)
 211 {
 212         u_int pageins;
 213         size_t len;
 214
 215         len = sizeof(pageins);
 216         if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
 217             != 0) {
 218                 warnx("v_swappgsin");
 219                 return (0);
 220         }
 221         return pageins;
 222 }