xref: /freebsd/sbin/reboot/reboot.c (revision a2aef24aa3c8458e4036735dd6928b4ef77294e5)
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 
30 #if 0
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1980, 1986, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #ifndef lint
38 static char sccsid[] = "@(#)reboot.c	8.1 (Berkeley) 6/5/93";
39 #endif /* not lint */
40 #endif
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <sys/reboot.h>
45 #include <sys/time.h>
46 #include <sys/types.h>
47 #include <sys/sysctl.h>
48 #include <signal.h>
49 #include <err.h>
50 #include <errno.h>
51 #include <fcntl.h>
52 #include <pwd.h>
53 #include <syslog.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 #include <utmpx.h>
59 
60 static void usage(void);
61 static u_int get_pageins(void);
62 
63 static int dohalt;
64 
65 int
66 main(int argc, char *argv[])
67 {
68 	struct utmpx utx;
69 	const struct passwd *pw;
70 	int ch, howto, i, fd, lflag, nflag, qflag, sverrno, Nflag;
71 	u_int pageins;
72 	const char *user, *kernel = NULL;
73 
74 	if (strcmp(getprogname(), "halt") == 0) {
75 		dohalt = 1;
76 		howto = RB_HALT;
77 	} else
78 		howto = 0;
79 	lflag = nflag = qflag = Nflag = 0;
80 	while ((ch = getopt(argc, argv, "cdk:lNnpqr")) != -1)
81 		switch(ch) {
82 		case 'c':
83 			howto |= RB_POWERCYCLE;
84 			break;
85 		case 'd':
86 			howto |= RB_DUMP;
87 			break;
88 		case 'k':
89 			kernel = optarg;
90 			break;
91 		case 'l':
92 			lflag = 1;
93 			break;
94 		case 'n':
95 			nflag = 1;
96 			howto |= RB_NOSYNC;
97 			break;
98 		case 'N':
99 			nflag = 1;
100 			Nflag = 1;
101 			break;
102 		case 'p':
103 			howto |= RB_POWEROFF;
104 			break;
105 		case 'q':
106 			qflag = 1;
107 			break;
108 		case 'r':
109 			howto |= RB_REROOT;
110 			break;
111 		case '?':
112 		default:
113 			usage();
114 		}
115 	argc -= optind;
116 	argv += optind;
117 
118 	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
119 		errx(1, "cannot dump (-d) when halting; must reboot instead");
120 	if (Nflag && (howto & RB_NOSYNC) != 0)
121 		errx(1, "-N cannot be used with -n");
122 	if ((howto & RB_POWEROFF) && (howto & RB_POWERCYCLE))
123 		errx(1, "-c and -p cannot be used together");
124 	if ((howto & RB_REROOT) != 0 && howto != RB_REROOT)
125 		errx(1, "-r cannot be used with -c, -d, -n, or -p");
126 	if (geteuid()) {
127 		errno = EPERM;
128 		err(1, NULL);
129 	}
130 
131 	if (qflag) {
132 		reboot(howto);
133 		err(1, NULL);
134 	}
135 
136 	if (kernel != NULL) {
137 		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
138 		    0444);
139 		if (fd > -1) {
140 			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
141 			(void)write(fd, "kernel=\"", 8L);
142 			(void)write(fd, kernel, strlen(kernel));
143 			(void)write(fd, "\"\n", 2);
144 			close(fd);
145 		}
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", 0, LOG_AUTH | LOG_CONS);
155 			syslog(LOG_CRIT, "halted by %s", user);
156 		} else if (howto & RB_REROOT) {
157 			openlog("reroot", 0, LOG_AUTH | LOG_CONS);
158 			syslog(LOG_CRIT, "rerooted by %s", user);
159 		} else if (howto & RB_POWEROFF) {
160 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
161 			syslog(LOG_CRIT, "powered off by %s", user);
162 		} else if (howto & RB_POWERCYCLE) {
163 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
164 			syslog(LOG_CRIT, "power cycled by %s", user);
165 		} else {
166 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
167 			syslog(LOG_CRIT, "rebooted by %s", user);
168 		}
169 	}
170 	utx.ut_type = SHUTDOWN_TIME;
171 	gettimeofday(&utx.ut_tv, NULL);
172 	pututxline(&utx);
173 
174 	/*
175 	 * Do a sync early on, so disks start transfers while we're off
176 	 * killing processes.  Don't worry about writes done before the
177 	 * processes die, the reboot system call syncs the disks.
178 	 */
179 	if (!nflag)
180 		sync();
181 
182 	/*
183 	 * Ignore signals that we can get as a result of killing
184 	 * parents, group leaders, etc.
185 	 */
186 	(void)signal(SIGHUP,  SIG_IGN);
187 	(void)signal(SIGINT,  SIG_IGN);
188 	(void)signal(SIGQUIT, SIG_IGN);
189 	(void)signal(SIGTERM, SIG_IGN);
190 	(void)signal(SIGTSTP, SIG_IGN);
191 
192 	/*
193 	 * If we're running in a pipeline, we don't want to die
194 	 * after killing whatever we're writing to.
195 	 */
196 	(void)signal(SIGPIPE, SIG_IGN);
197 
198 	/*
199 	 * Only init(8) can perform rerooting.
200 	 */
201 	if (howto & RB_REROOT) {
202 		if (kill(1, SIGEMT) == -1)
203 			err(1, "SIGEMT init");
204 
205 		return (0);
206 	}
207 
208 	/* Just stop init -- if we fail, we'll restart it. */
209 	if (kill(1, SIGTSTP) == -1)
210 		err(1, "SIGTSTP init");
211 
212 	/* Send a SIGTERM first, a chance to save the buffers. */
213 	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
214 		err(1, "SIGTERM processes");
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 give everybody a chance. If there is a lot of
220 	 * paging activity then wait longer, up to a maximum of approx
221 	 * 60 seconds.
222 	 */
223 	sleep(2);
224 	for (i = 0; i < 20; i++) {
225 		pageins = get_pageins();
226 		if (!nflag)
227 			sync();
228 		sleep(3);
229 		if (get_pageins() == pageins)
230 			break;
231 	}
232 
233 	for (i = 1;; ++i) {
234 		if (kill(-1, SIGKILL) == -1) {
235 			if (errno == ESRCH)
236 				break;
237 			goto restart;
238 		}
239 		if (i > 5) {
240 			(void)fprintf(stderr,
241 			    "WARNING: some process(es) wouldn't die\n");
242 			break;
243 		}
244 		(void)sleep(2 * i);
245 	}
246 
247 	reboot(howto);
248 	/* FALLTHROUGH */
249 
250 restart:
251 	sverrno = errno;
252 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
253 	    strerror(sverrno));
254 	/* NOTREACHED */
255 }
256 
257 static void
258 usage(void)
259 {
260 
261 	(void)fprintf(stderr, dohalt ?
262 	    "usage: halt [-lNnpq] [-k kernel]\n" :
263 	    "usage: reboot [-dlNnpqr] [-k kernel]\n");
264 	exit(1);
265 }
266 
267 static u_int
268 get_pageins(void)
269 {
270 	u_int pageins;
271 	size_t len;
272 
273 	len = sizeof(pageins);
274 	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
275 	    != 0) {
276 		warnx("v_swappgsin");
277 		return (0);
278 	}
279 	return pageins;
280 }
281