reboot.c revision 1558 
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. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char copyright[] =
36"@(#) Copyright (c) 1980, 1986, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)reboot.c	8.1 (Berkeley) 6/5/93";
42#endif /* not lint */
43
44#include <sys/reboot.h>
45#include <signal.h>
46#include <pwd.h>
47#include <errno.h>
48#include <syslog.h>
49#include <unistd.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53
54void err __P((const char *fmt, ...));
55void usage __P((void));
56
57int dohalt;
58
59int
60main(argc, argv)
61	int argc;
62	char *argv[];
63{
64	register int i;
65	struct passwd *pw;
66	int ch, howto, lflag, nflag, qflag, sverrno;
67	char *p, *user;
68
69	if (!strcmp((p = rindex(*argv, '/')) ? p + 1 : *argv, "halt")) {
70		dohalt = 1;
71		howto = RB_HALT;
72	} else
73		howto = 0;
74	lflag = nflag = qflag = 0;
75	while ((ch = getopt(argc, argv, "lnq")) != EOF)
76		switch(ch) {
77		case 'l':		/* Undocumented; used by shutdown. */
78			lflag = 1;
79			break;
80		case 'n':
81			nflag = 1;
82			howto |= RB_NOSYNC;
83			break;
84		case 'q':
85			qflag = 1;
86			break;
87		case '?':
88		default:
89			usage();
90		}
91	argc -= optind;
92	argv += optind;
93
94	if (geteuid())
95		err("%s", strerror(EPERM));
96
97	if (qflag) {
98		reboot(howto);
99		err("%s", strerror(errno));
100	}
101
102	/* Log the reboot. */
103	if (!lflag)  {
104		if ((user = getlogin()) == NULL)
105			user = (pw = getpwuid(getuid())) ?
106			    pw->pw_name : "???";
107		if (dohalt) {
108			openlog("halt", 0, LOG_AUTH | LOG_CONS);
109			syslog(LOG_CRIT, "halted by %s", user);
110		} else {
111			openlog("reboot", 0, LOG_AUTH | LOG_CONS);
112			syslog(LOG_CRIT, "rebooted by %s", user);
113		}
114	}
115	logwtmp("~", "shutdown", "");
116
117	/*
118	 * Do a sync early on, so disks start transfers while we're off
119	 * killing processes.  Don't worry about writes done before the
120	 * processes die, the reboot system call syncs the disks.
121	 */
122	if (!nflag)
123		sync();
124
125	/* Just stop init -- if we fail, we'll restart it. */
126	if (kill(1, SIGTSTP) == -1)
127		err("SIGTSTP init: %s", strerror(errno));
128
129	/* Ignore the SIGHUP we get when our parent shell dies. */
130	(void)signal(SIGHUP, SIG_IGN);
131
132	/* Send a SIGTERM first, a chance to save the buffers. */
133	if (kill(-1, SIGTERM) == -1)
134		err("SIGTERM processes: %s", strerror(errno));
135
136	/*
137	 * After the processes receive the signal, start the rest of the
138	 * buffers on their way.  Wait 5 seconds between the SIGTERM and
139	 * the SIGKILL to give everybody a chance.
140	 */
141	sleep(2);
142	if (!nflag)
143		sync();
144	sleep(3);
145
146	for (i = 1;; ++i) {
147		if (kill(-1, SIGKILL) == -1) {
148			if (errno == ESRCH)
149				break;
150			goto restart;
151		}
152		if (i > 5) {
153			(void)fprintf(stderr,
154			    "WARNING: some process(es) wouldn't die\n");
155			break;
156		}
157		(void)sleep(2 * i);
158	}
159
160	reboot(howto);
161	/* FALLTHROUGH */
162
163restart:
164	sverrno = errno;
165	err("%s%s", kill(1, SIGHUP) == -1 ? "(can't restart init): " : "",
166	    strerror(sverrno));
167	/* NOTREACHED */
168}
169
170void
171usage()
172{
173	(void)fprintf(stderr, "usage: %s [-nq]\n", dohalt ? "halt" : "reboot");
174	exit(1);
175}
176
177#if __STDC__
178#include <stdarg.h>
179#else
180#include <varargs.h>
181#endif
182
183void
184#if __STDC__
185err(const char *fmt, ...)
186#else
187err(fmt, va_alist)
188	char *fmt;
189        va_dcl
190#endif
191{
192	va_list ap;
193#if __STDC__
194	va_start(ap, fmt);
195#else
196	va_start(ap);
197#endif
198	(void)fprintf(stderr, "%s: ", dohalt ? "halt" : "reboot");
199	(void)vfprintf(stderr, fmt, ap);
200	va_end(ap);
201	(void)fprintf(stderr, "\n");
202	exit(1);
203	/* NOTREACHED */
204}
205