xref: /freebsd/sbin/reboot/reboot.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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/types.h>
46 #include <sys/sysctl.h>
47 #include <signal.h>
48 #include <err.h>
49 #include <errno.h>
50 #include <fcntl.h>
51 #include <libutil.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 
59 static void usage(void);
60 static u_int get_pageins(void);
61 
62 int dohalt;
63 
64 int
65 main(int argc, char *argv[])
66 {
67 	const struct passwd *pw;
68 	int ch, howto, i, fd, lflag, nflag, qflag, pflag, sverrno;
69 	u_int pageins;
70 	const char *p, *user, *kernel = NULL;
71 
72 	if (strstr((p = rindex(*argv, '/')) ? p + 1 : *argv, "halt")) {
73 		dohalt = 1;
74 		howto = RB_HALT;
75 	} else
76 		howto = 0;
77 	lflag = nflag = qflag = 0;
78 	while ((ch = getopt(argc, argv, "dk:lnpq")) != -1)
79 		switch(ch) {
80 		case 'd':
81 			howto |= RB_DUMP;
82 			break;
83 		case 'k':
84 			kernel = optarg;
85 			break;
86 		case 'l':
87 			lflag = 1;
88 			break;
89 		case 'n':
90 			nflag = 1;
91 			howto |= RB_NOSYNC;
92 			break;
93 		case 'p':
94 			pflag = 1;
95 			howto |= RB_POWEROFF;
96 			break;
97 		case 'q':
98 			qflag = 1;
99 			break;
100 		case '?':
101 		default:
102 			usage();
103 		}
104 	argc -= optind;
105 	argv += optind;
106 
107 	if ((howto & (RB_DUMP | RB_HALT)) == (RB_DUMP | RB_HALT))
108 		errx(1, "cannot dump (-d) when halting; must reboot instead");
109 	if (geteuid()) {
110 		errno = EPERM;
111 		err(1, NULL);
112 	}
113 
114 	if (qflag) {
115 		reboot(howto);
116 		err(1, NULL);
117 	}
118 
119 	if (kernel != NULL) {
120 		fd = open("/boot/nextboot.conf", O_WRONLY | O_CREAT | O_TRUNC,
121 		    0444);
122 		if (fd > -1) {
123 			(void)write(fd, "nextboot_enable=\"YES\"\n", 22);
124 			(void)write(fd, "kernel=\"", 8L);
125 			(void)write(fd, kernel, strlen(kernel));
126 			(void)write(fd, "\"\n", 2);
127 			close(fd);
128 		}
129 	}
130 
131 	/* Log the reboot. */
132 	if (!lflag)  {
133 		if ((user = getlogin()) == NULL)
134 			user = (pw = getpwuid(getuid())) ?
135 			    pw->pw_name : "???";
136 		if (dohalt) {
137 			openlog("halt", 0, LOG_AUTH | LOG_CONS);
138 			syslog(LOG_CRIT, "halted by %s", user);
139 		} else {
140 			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
141 			syslog(LOG_CRIT, "rebooted by %s", user);
142 		}
143 	}
144 	logwtmp("~", "shutdown", "");
145 
146 	/*
147 	 * Do a sync early on, so disks start transfers while we're off
148 	 * killing processes.  Don't worry about writes done before the
149 	 * processes die, the reboot system call syncs the disks.
150 	 */
151 	if (!nflag)
152 		sync();
153 
154 	/*
155 	 * Ignore signals that we can get as a result of killing
156 	 * parents, group leaders, etc.
157 	 */
158 	(void)signal(SIGHUP,  SIG_IGN);
159 	(void)signal(SIGINT,  SIG_IGN);
160 	(void)signal(SIGQUIT, SIG_IGN);
161 	(void)signal(SIGTERM, SIG_IGN);
162 	(void)signal(SIGTSTP, SIG_IGN);
163 
164 	/*
165 	 * If we're running in a pipeline, we don't want to die
166 	 * after killing whatever we're writing to.
167 	 */
168 	(void)signal(SIGPIPE, SIG_IGN);
169 
170 	/* Just stop init -- if we fail, we'll restart it. */
171 	if (kill(1, SIGTSTP) == -1)
172 		err(1, "SIGTSTP init");
173 
174 	/* Send a SIGTERM first, a chance to save the buffers. */
175 	if (kill(-1, SIGTERM) == -1 && errno != ESRCH)
176 		err(1, "SIGTERM processes");
177 
178 	/*
179 	 * After the processes receive the signal, start the rest of the
180 	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
181 	 * the SIGKILL to give everybody a chance. If there is a lot of
182 	 * paging activity then wait longer, up to a maximum of approx
183 	 * 60 seconds.
184 	 */
185 	sleep(2);
186 	for (i = 0; i < 20; i++) {
187 		pageins = get_pageins();
188 		if (!nflag)
189 			sync();
190 		sleep(3);
191 		if (get_pageins() == pageins)
192 			break;
193 	}
194 
195 	for (i = 1;; ++i) {
196 		if (kill(-1, SIGKILL) == -1) {
197 			if (errno == ESRCH)
198 				break;
199 			goto restart;
200 		}
201 		if (i > 5) {
202 			(void)fprintf(stderr,
203 			    "WARNING: some process(es) wouldn't die\n");
204 			break;
205 		}
206 		(void)sleep(2 * i);
207 	}
208 
209 	reboot(howto);
210 	/* FALLTHROUGH */
211 
212 restart:
213 	sverrno = errno;
214 	errx(1, "%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
215 	    strerror(sverrno));
216 	/* NOTREACHED */
217 }
218 
219 static void
220 usage()
221 {
222 	(void)fprintf(stderr, "usage: %s [-%slnpq] [-k kernel]\n",
223 	    getprogname(), dohalt ? "" : "d");
224 	exit(1);
225 }
226 
227 static u_int
228 get_pageins()
229 {
230 	u_int pageins;
231 	size_t len;
232 
233 	len = sizeof(pageins);
234 	if (sysctlbyname("vm.stats.vm.v_swappgsin", &pageins, &len, NULL, 0)
235 	    != 0) {
236 		warnx("v_swappgsin");
237 		return (0);
238 	}
239 	return pageins;
240 }
241