xref: /netbsd/sbin/reboot/reboot.c (revision 6cdd6deb)
1 /*	$NetBSD: reboot.c,v 1.41 2019/08/08 21:14:12 roy 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 1.41 2019/08/08 21:14:12 roy 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 #ifdef SUPPORT_UTMPX
60 #include <utmpx.h>
61 #endif
62 
63 __dead static void usage(void);
64 
65 static int dohalt;
66 static int dopoweroff;
67 
68 int
main(int argc,char * argv[])69 main(int argc, char *argv[])
70 {
71 	const char *progname;
72 	int i;
73 	struct passwd *pw;
74 	int ch, howto, lflag, nflag, qflag, sverrno, len;
75 	const char *user;
76 	char *bootstr, **av;
77 
78 	progname = getprogname();
79 	if (progname[0] == '-')
80 		progname++;
81 	if (strcmp(progname, "halt") == 0) {
82 		dohalt = 1;
83 		howto = RB_HALT;
84 	} else if (strcmp(progname, "poweroff") == 0) {
85 		dopoweroff = 1;
86 		howto = RB_HALT | RB_POWERDOWN;
87 	} else
88 		howto = 0;
89 	lflag = nflag = qflag = 0;
90 	while ((ch = getopt(argc, argv, "dlnpqvxz")) != -1)
91 		switch(ch) {
92 		case 'd':
93 			howto |= RB_DUMP;
94 			break;
95 		case 'l':
96 			lflag = 1;
97 			break;
98 		case 'n':
99 			nflag = 1;
100 			howto |= RB_NOSYNC;
101 			break;
102 		case 'p':
103 			if (dohalt == 0)
104 				usage();
105 			howto |= RB_POWERDOWN;
106 			break;
107 		case 'q':
108 			qflag = 1;
109 			break;
110 		case 'v':
111 			howto |= AB_VERBOSE;
112 			break;
113 		case 'x':
114 			howto |= AB_DEBUG;
115 			break;
116 		case 'z':
117 			howto |= AB_SILENT;
118 			break;
119 		case '?':
120 		default:
121 			usage();
122 		}
123 	argc -= optind;
124 	argv += optind;
125 
126 	if (argc) {
127 		for (av = argv, len = 0; *av; av++)
128 			len += strlen(*av) + 1;
129 		bootstr = malloc(len + 1);
130 		*bootstr = '\0';		/* for first strcat */
131 		for (av = argv; *av; av++) {
132 			strcat(bootstr, *av);
133 			strcat(bootstr, " ");
134 		}
135 		bootstr[len - 1] = '\0';	/* to kill last space */
136 		howto |= RB_STRING;
137 	} else
138 		bootstr = NULL;
139 
140 	if (geteuid())
141 		errx(1, "%s", strerror(EPERM));
142 
143 	if (qflag) {
144 		reboot(howto, bootstr);
145 		err(1, "reboot");
146 	}
147 
148 	/* Log the reboot. */
149 	if (!lflag)  {
150 		if ((user = getlogin()) == NULL)
151 			user = (pw = getpwuid(getuid())) ?
152 			    pw->pw_name : "???";
153 		if (dohalt) {
154 			openlog("halt", LOG_CONS, LOG_AUTH);
155 			syslog(LOG_CRIT, "halted by %s", user);
156 		} else if (dopoweroff) {
157 			openlog("poweroff", LOG_CONS, LOG_AUTH);
158 			syslog(LOG_CRIT, "powered off by %s", user);
159 		} else {
160 			openlog("reboot", LOG_CONS, LOG_AUTH);
161 			if (bootstr)
162 				syslog(LOG_CRIT, "rebooted by %s: %s", user,
163 				    bootstr);
164 			else
165 				syslog(LOG_CRIT, "rebooted by %s", user);
166 		}
167 	}
168 #ifdef SUPPORT_UTMP
169 	logwtmp("~", "shutdown", "");
170 #endif
171 #ifdef SUPPORT_UTMPX
172 	logwtmpx("~", "shutdown", "", 0, INIT_PROCESS);
173 #endif
174 
175 	/*
176 	 * Do a sync early on, so disks start transfers while we're off
177 	 * killing processes.  Don't worry about writes done before the
178 	 * processes die, the reboot system call syncs the disks.
179 	 */
180 	if (!nflag)
181 		sync();
182 
183 	/*
184 	 * Ignore signals that we can get as a result of killing
185 	 * parents, group leaders, etc.
186 	 */
187 	(void)signal(SIGHUP,  SIG_IGN);
188 	(void)signal(SIGINT,  SIG_IGN);
189 	(void)signal(SIGQUIT, SIG_IGN);
190 	(void)signal(SIGTERM, SIG_IGN);
191 	(void)signal(SIGTSTP, SIG_IGN);
192 
193 	/*
194 	 * If we're running in a pipeline, we don't want to die
195 	 * after killing whatever we're writing to.
196 	 */
197 	(void)signal(SIGPIPE, SIG_IGN);
198 
199 	/* Just stop init -- if we fail, we'll restart it. */
200 	if (kill(1, SIGTSTP) == -1)
201 		err(1, "SIGTSTP init");
202 
203 	/* Send a SIGTERM first, a chance to save the buffers. */
204 	if (kill(-1, SIGTERM) == -1) {
205 		/*
206 		 * If ESRCH, everything's OK: we're the only non-system
207 		 * process!  That can happen e.g. via 'exec reboot' in
208 		 * single-user mode.
209 		 */
210 		if (errno != ESRCH) {
211 			warn("SIGTERM all processes");
212 			goto restart;
213 		}
214 	}
215 
216 	/*
217 	 * After the processes receive the signal, start the rest of the
218 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
219 	 * the SIGKILL to pretend to give everybody a chance.
220 	 */
221 	sleep(2);
222 	if (!nflag)
223 		sync();
224 	sleep(3);
225 
226 	for (i = 1;; ++i) {
227 		if (kill(-1, SIGKILL) == -1) {
228 			if (errno == ESRCH)
229 				break;
230 			warn("SIGKILL all processes");
231 			goto restart;
232 		}
233 		if (i > 5) {
234 			warnx("WARNING: some process(es) wouldn't die");
235 			break;
236 		}
237 		(void)sleep(2 * i);
238 	}
239 
240 	reboot(howto, bootstr);
241 	warn("reboot()");
242 	/* FALLTHROUGH */
243 
244 restart:
245 	sverrno = errno;
246 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
247 	    strerror(sverrno));
248 	/* NOTREACHED */
249 }
250 
251 static void
usage(void)252 usage(void)
253 {
254 	const char *pflag = dohalt ? "p" : "";
255 
256 	(void)fprintf(stderr, "usage: %s [-dln%sqvxz] [-- <boot string>]\n",
257 	    getprogname(), pflag);
258 	exit(1);
259 }
260