xref: /freebsd/sbin/reboot/reboot.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
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  * 4. 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;
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 = 0;
80 	while ((ch = getopt(argc, argv, "dk:lnpq")) != -1)
81 		switch(ch) {
82 		case 'd':
83 			howto |= RB_DUMP;
84 			break;
85 		case 'k':
86 			kernel = optarg;
87 			break;
88 		case 'l':
89 			lflag = 1;
90 			break;
91 		case 'n':
92 			nflag = 1;
93 			howto |= RB_NOSYNC;
94 			break;
95 		case 'p':
96 			howto |= RB_POWEROFF;
97 			break;
98 		case 'q':
99 			qflag = 1;
100 			break;
101 		case '?':
102 		default:
103 			usage();
104 		}
105 	argc -= optind;
106 	argv += optind;
107 
108 	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
109 		errx(1, "cannot dump (-d) when halting; must reboot instead");
110 	if (geteuid()) {
111 		errno = EPERM;
112 		err(1, NULL);
113 	}
114 
115 	if (qflag) {
116 		reboot(howto);
117 		err(1, NULL);
118 	}
119 
120 	if (kernel != NULL) {
121 		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
122 		    0444);
123 		if (fd > -1) {
124 			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
125 			(void)write(fd, "kernel=\"", 8L);
126 			(void)write(fd, kernel, strlen(kernel));
127 			(void)write(fd, "\"\n", 2);
128 			close(fd);
129 		}
130 	}
131 
132 	/* Log the reboot. */
133 	if (!lflag)  {
134 		if ((user = getlogin()) == NULL)
135 			user = (pw = getpwuid(getuid())) ?
136 			    pw->pw_name : "???";
137 		if (dohalt) {
138 			openlog("halt", 0, LOG_AUTH | LOG_CONS);
139 			syslog(LOG_CRIT, "halted by %s", user);
140 		} else {
141 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
142 			syslog(LOG_CRIT, "rebooted by %s", user);
143 		}
144 	}
145 	utx.ut_type = SHUTDOWN_TIME;
146 	gettimeofday(&utx.ut_tv, NULL);
147 	pututxline(&utx);
148 
149 	/*
150 	 * Do a sync early on, so disks start transfers while we're off
151 	 * killing processes.  Don't worry about writes done before the
152 	 * processes die, the reboot system call syncs the disks.
153 	 */
154 	if (!nflag)
155 		sync();
156 
157 	/*
158 	 * Ignore signals that we can get as a result of killing
159 	 * parents, group leaders, etc.
160 	 */
161 	(void)signal(SIGHUP,  SIG_IGN);
162 	(void)signal(SIGINT,  SIG_IGN);
163 	(void)signal(SIGQUIT, SIG_IGN);
164 	(void)signal(SIGTERM, SIG_IGN);
165 	(void)signal(SIGTSTP, SIG_IGN);
166 
167 	/*
168 	 * If we're running in a pipeline, we don't want to die
169 	 * after killing whatever we're writing to.
170 	 */
171 	(void)signal(SIGPIPE, SIG_IGN);
172 
173 	/* Just stop init -- if we fail, we'll restart it. */
174 	if (kill(1, SIGTSTP) == -1)
175 		err(1, "SIGTSTP init");
176 
177 	/* Send a SIGTERM first, a chance to save the buffers. */
178 	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
179 		err(1, "SIGTERM processes");
180 
181 	/*
182 	 * After the processes receive the signal, start the rest of the
183 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
184 	 * the SIGKILL to give everybody a chance. If there is a lot of
185 	 * paging activity then wait longer, up to a maximum of approx
186 	 * 60 seconds.
187 	 */
188 	sleep(2);
189 	for (i = 0; i < 20; i++) {
190 		pageins = get_pageins();
191 		if (!nflag)
192 			sync();
193 		sleep(3);
194 		if (get_pageins() == pageins)
195 			break;
196 	}
197 
198 	for (i = 1;; ++i) {
199 		if (kill(-1, SIGKILL) == -1) {
200 			if (errno == ESRCH)
201 				break;
202 			goto restart;
203 		}
204 		if (i > 5) {
205 			(void)fprintf(stderr,
206 			    "WARNING: some process(es) wouldn't die\n");
207 			break;
208 		}
209 		(void)sleep(2 * i);
210 	}
211 
212 	reboot(howto);
213 	/* FALLTHROUGH */
214 
215 restart:
216 	sverrno = errno;
217 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
218 	    strerror(sverrno));
219 	/* NOTREACHED */
220 }
221 
222 static void
223 usage(void)
224 {
225 
226 	(void)fprintf(stderr, dohalt ?
227 	    "usage: halt [-lnpq] [-k kernel]\n" :
228 	    "usage: reboot [-dlnpq] [-k kernel]\n");
229 	exit(1);
230 }
231 
232 static u_int
233 get_pageins(void)
234 {
235 	u_int pageins;
236 	size_t len;
237 
238 	len = sizeof(pageins);
239 	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
240 	    != 0) {
241 		warnx("v_swappgsin");
242 		return (0);
243 	}
244 	return pageins;
245 }
246