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reboot.c revision 1.37
      1 /*	$NetBSD: reboot.c,v 1.37 2011/02/16 17:53:31 dyoung Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1980, 1986, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 
     34 #ifndef lint
     35 __COPYRIGHT("@(#) Copyright (c) 1980, 1986, 1993\
     36  The Regents of the University of California.  All rights reserved.");
     37 #endif /* not lint */
     38 
     39 #ifndef lint
     40 #if 0
     41 static char sccsid[] = "@(#)reboot.c	8.1 (Berkeley) 6/5/93";
     42 #else
     43 __RCSID("$NetBSD: reboot.c,v 1.37 2011/02/16 17:53:31 dyoung Exp $");
     44 #endif
     45 #endif /* not lint */
     46 
     47 #include <sys/reboot.h>
     48 
     49 #include <err.h>
     50 #include <errno.h>
     51 #include <pwd.h>
     52 #include <signal.h>
     53 #include <stdio.h>
     54 #include <stdlib.h>
     55 #include <string.h>
     56 #include <syslog.h>
     57 #include <unistd.h>
     58 #include <util.h>
     59 
     60 int main(int, char *[]);
     61 void usage(void);
     62 
     63 int dohalt;
     64 int dopoweroff;
     65 
     66 int
     67 main(int argc, char *argv[])
     68 {
     69 	const char *progname;
     70 	int i;
     71 	struct passwd *pw;
     72 	int ch, howto, lflag, nflag, qflag, sverrno, len;
     73 	const char *user;
     74 	char *bootstr, **av;
     75 
     76 	progname = getprogname();
     77 	if (progname[0] == '-')
     78 		progname++;
     79 	if (strcmp(progname, "halt") == 0) {
     80 		dohalt = 1;
     81 		howto = RB_HALT;
     82 	} else if (strcmp(progname, "poweroff") == 0) {
     83 		dopoweroff = 1;
     84 		howto = RB_HALT | RB_POWERDOWN;
     85 	} else
     86 		howto = 0;
     87 	lflag = nflag = qflag = 0;
     88 	while ((ch = getopt(argc, argv, "dlnpqvxz")) != -1)
     89 		switch(ch) {
     90 		case 'd':
     91 			howto |= RB_DUMP;
     92 			break;
     93 		case 'l':
     94 			lflag = 1;
     95 			break;
     96 		case 'n':
     97 			nflag = 1;
     98 			howto |= RB_NOSYNC;
     99 			break;
    100 		case 'p':
    101 			if (dohalt == 0)
    102 				usage();
    103 			howto |= RB_POWERDOWN;
    104 			break;
    105 		case 'q':
    106 			qflag = 1;
    107 			break;
    108 		case 'v':
    109 			howto |= AB_VERBOSE;
    110 			break;
    111 		case 'x':
    112 			howto |= AB_DEBUG;
    113 			break;
    114 		case 'z':
    115 			howto |= AB_SILENT;
    116 			break;
    117 		case '?':
    118 		default:
    119 			usage();
    120 		}
    121 	argc -= optind;
    122 	argv += optind;
    123 
    124 	if (argc) {
    125 		for (av = argv, len = 0; *av; av++)
    126 			len += strlen(*av) + 1;
    127 		bootstr = malloc(len + 1);
    128 		*bootstr = '\0';		/* for first strcat */
    129 		for (av = argv; *av; av++) {
    130 			strcat(bootstr, *av);
    131 			strcat(bootstr, " ");
    132 		}
    133 		bootstr[len - 1] = '\0';	/* to kill last space */
    134 		howto |= RB_STRING;
    135 	} else
    136 		bootstr = NULL;
    137 
    138 	if (geteuid())
    139 		errx(1, "%s", strerror(EPERM));
    140 
    141 	if (qflag) {
    142 		reboot(howto, bootstr);
    143 		err(1, "reboot");
    144 	}
    145 
    146 	/* Log the reboot. */
    147 	if (!lflag)  {
    148 		if ((user = getlogin()) == NULL)
    149 			user = (pw = getpwuid(getuid())) ?
    150 			    pw->pw_name : "???";
    151 		if (dohalt) {
    152 			openlog("halt", LOG_CONS, LOG_AUTH);
    153 			syslog(LOG_CRIT, "halted by %s", user);
    154 		} else if (dopoweroff) {
    155 			openlog("poweroff", LOG_CONS, LOG_AUTH);
    156 			syslog(LOG_CRIT, "powered off by %s", user);
    157 		} else {
    158 			openlog("reboot", LOG_CONS, LOG_AUTH);
    159 			if (bootstr)
    160 				syslog(LOG_CRIT, "rebooted by %s: %s", user,
    161 				    bootstr);
    162 			else
    163 				syslog(LOG_CRIT, "rebooted by %s", user);
    164 		}
    165 	}
    166 #ifdef SUPPORT_UTMP
    167 	logwtmp("~", "shutdown", "");
    168 #endif
    169 #ifdef SUPPORT_UTMPX
    170 	logwtmpx("~", "shutdown", "", INIT_PROCESS, 0);
    171 #endif
    172 
    173 	/*
    174 	 * Do a sync early on, so disks start transfers while we're off
    175 	 * killing processes.  Don't worry about writes done before the
    176 	 * processes die, the reboot system call syncs the disks.
    177 	 */
    178 	if (!nflag)
    179 		sync();
    180 
    181 	/*
    182 	 * Ignore signals that we can get as a result of killing
    183 	 * parents, group leaders, etc.
    184 	 */
    185 	(void)signal(SIGHUP,  SIG_IGN);
    186 	(void)signal(SIGINT,  SIG_IGN);
    187 	(void)signal(SIGQUIT, SIG_IGN);
    188 	(void)signal(SIGTERM, SIG_IGN);
    189 	(void)signal(SIGTSTP, SIG_IGN);
    190 
    191 	/*
    192 	 * If we're running in a pipeline, we don't want to die
    193 	 * after killing whatever we're writing to.
    194 	 */
    195 	(void)signal(SIGPIPE, SIG_IGN);
    196 
    197 	/* Just stop init -- if we fail, we'll restart it. */
    198 	if (kill(1, SIGTSTP) == -1)
    199 		err(1, "SIGTSTP init");
    200 
    201 	/* Send a SIGTERM first, a chance to save the buffers. */
    202 	if (kill(-1, SIGTERM) == -1) {
    203 		/*
    204 		 * If ESRCH, everything's OK: we're the only non-system
    205 		 * process!  That can happen e.g. via 'exec reboot' in
    206 		 * single-user mode.
    207 		 */
    208 		if (errno != ESRCH) {
    209 			warn("SIGTERM all processes");
    210 			goto restart;
    211 		}
    212 	}
    213 
    214 	/*
    215 	 * After the processes receive the signal, start the rest of the
    216 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
    217 	 * the SIGKILL to pretend to give everybody a chance.
    218 	 */
    219 	sleep(2);
    220 	if (!nflag)
    221 		sync();
    222 	sleep(3);
    223 
    224 	for (i = 1;; ++i) {
    225 		if (kill(-1, SIGKILL) == -1) {
    226 			if (errno == ESRCH)
    227 				break;
    228 			warn("SIGKILL all processes");
    229 			goto restart;
    230 		}
    231 		if (i > 5) {
    232 			warnx("WARNING: some process(es) wouldn't die");
    233 			break;
    234 		}
    235 		(void)sleep(2 * i);
    236 	}
    237 
    238 	reboot(howto, bootstr);
    239 	warn("reboot()");
    240 	/* FALLTHROUGH */
    241 
    242 restart:
    243 	sverrno = errno;
    244 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
    245 	    strerror(sverrno));
    246 	/* NOTREACHED */
    247 }
    248 
    249 void
    250 usage(void)
    251 {
    252 	const char *pflag = dohalt ? "p" : "";
    253 
    254 	(void)fprintf(stderr, "usage: %s [-dln%sq] [-- <boot string>]\n",
    255 	    getprogname(), pflag);
    256 	exit(1);
    257 }
    258