xref: /freebsd/usr.sbin/daemon/daemon.c (revision c6262cb601a0159637789563708f64368c30537c)
1bd06a3ecSMike Barcroft /*-
2bd06a3ecSMike Barcroft  * Copyright (c) 1999 Berkeley Software Design, Inc. All rights reserved.
3bd06a3ecSMike Barcroft  *
4bd06a3ecSMike Barcroft  * Redistribution and use in source and binary forms, with or without
5bd06a3ecSMike Barcroft  * modification, are permitted provided that the following conditions
6bd06a3ecSMike Barcroft  * are met:
7bd06a3ecSMike Barcroft  * 1. Redistributions of source code must retain the above copyright
8bd06a3ecSMike Barcroft  *    notice, this list of conditions and the following disclaimer.
9bd06a3ecSMike Barcroft  * 2. Redistributions in binary form must reproduce the above copyright
10bd06a3ecSMike Barcroft  *    notice, this list of conditions and the following disclaimer in the
11bd06a3ecSMike Barcroft  *    documentation and/or other materials provided with the distribution.
12bd06a3ecSMike Barcroft  * 3. Berkeley Software Design Inc's name may not be used to endorse or
13bd06a3ecSMike Barcroft  *    promote products derived from this software without specific prior
14bd06a3ecSMike Barcroft  *    written permission.
15bd06a3ecSMike Barcroft  *
16bd06a3ecSMike Barcroft  * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND
17bd06a3ecSMike Barcroft  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18bd06a3ecSMike Barcroft  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19bd06a3ecSMike Barcroft  * ARE DISCLAIMED.  IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE
20bd06a3ecSMike Barcroft  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21bd06a3ecSMike Barcroft  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22bd06a3ecSMike Barcroft  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23bd06a3ecSMike Barcroft  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24bd06a3ecSMike Barcroft  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25bd06a3ecSMike Barcroft  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26bd06a3ecSMike Barcroft  * SUCH DAMAGE.
27bd06a3ecSMike Barcroft  *
28bd06a3ecSMike Barcroft  *	From BSDI: daemon.c,v 1.2 1996/08/15 01:11:09 jch Exp
29bd06a3ecSMike Barcroft  */
30bd06a3ecSMike Barcroft 
3154ede02dSPhilippe Charnier #include <sys/cdefs.h>
3254ede02dSPhilippe Charnier __FBSDID("$FreeBSD$");
3354ede02dSPhilippe Charnier 
34c6262cb6SPawel Jakub Dawidek #include <sys/param.h>
35bd06a3ecSMike Barcroft 
36bd06a3ecSMike Barcroft #include <err.h>
37846be7bdSPoul-Henning Kamp #include <errno.h>
38c6262cb6SPawel Jakub Dawidek #include <libutil.h>
39bd06a3ecSMike Barcroft #include <stdio.h>
40bd06a3ecSMike Barcroft #include <stdlib.h>
41bd06a3ecSMike Barcroft #include <unistd.h>
42bd06a3ecSMike Barcroft 
43bd06a3ecSMike Barcroft static void usage(void);
44bd06a3ecSMike Barcroft 
45bd06a3ecSMike Barcroft int
46bd06a3ecSMike Barcroft main(int argc, char *argv[])
47bd06a3ecSMike Barcroft {
48c6262cb6SPawel Jakub Dawidek 	struct pidfh *pfh;
49846be7bdSPoul-Henning Kamp 	int ch, nochdir, noclose, errcode;
50846be7bdSPoul-Henning Kamp 	const char *pidfile;
51c6262cb6SPawel Jakub Dawidek 	pid_t otherpid;
52bd06a3ecSMike Barcroft 
53bd06a3ecSMike Barcroft 	nochdir = noclose = 1;
54846be7bdSPoul-Henning Kamp 	pidfile = NULL;
55846be7bdSPoul-Henning Kamp 	while ((ch = getopt(argc, argv, "-cfp:")) != -1) {
56bd06a3ecSMike Barcroft 		switch (ch) {
57bd06a3ecSMike Barcroft 		case 'c':
58bd06a3ecSMike Barcroft 			nochdir = 0;
59bd06a3ecSMike Barcroft 			break;
60bd06a3ecSMike Barcroft 		case 'f':
61bd06a3ecSMike Barcroft 			noclose = 0;
62bd06a3ecSMike Barcroft 			break;
63846be7bdSPoul-Henning Kamp 		case 'p':
64846be7bdSPoul-Henning Kamp 			pidfile = optarg;
65846be7bdSPoul-Henning Kamp 			break;
66bd06a3ecSMike Barcroft 		default:
67bd06a3ecSMike Barcroft 			usage();
68bd06a3ecSMike Barcroft 		}
69bd06a3ecSMike Barcroft 	}
70bd06a3ecSMike Barcroft 	argc -= optind;
71bd06a3ecSMike Barcroft 	argv += optind;
72bd06a3ecSMike Barcroft 
73bd06a3ecSMike Barcroft 	if (argc == 0)
74bd06a3ecSMike Barcroft 		usage();
75846be7bdSPoul-Henning Kamp 	/*
76846be7bdSPoul-Henning Kamp 	 * Try to open the pidfile before calling daemon(3),
77846be7bdSPoul-Henning Kamp 	 * to be able to report the error intelligently
78846be7bdSPoul-Henning Kamp 	 */
79846be7bdSPoul-Henning Kamp 	if (pidfile) {
80c6262cb6SPawel Jakub Dawidek 		pfh = pidfile_open(pidfile, 0600, &otherpid);
81c6262cb6SPawel Jakub Dawidek 		if (pfh == NULL) {
82c6262cb6SPawel Jakub Dawidek 			if (errno == EEXIST) {
83c6262cb6SPawel Jakub Dawidek 				errx(3, "process already running, pid: %d",
84c6262cb6SPawel Jakub Dawidek 				    otherpid);
85c6262cb6SPawel Jakub Dawidek 			}
86846be7bdSPoul-Henning Kamp 			err(2, "pidfile ``%s''", pidfile);
87846be7bdSPoul-Henning Kamp 		}
88c6262cb6SPawel Jakub Dawidek 	}
89846be7bdSPoul-Henning Kamp 
90bd06a3ecSMike Barcroft 	if (daemon(nochdir, noclose) == -1)
91bd06a3ecSMike Barcroft 		err(1, NULL);
92846be7bdSPoul-Henning Kamp 
93846be7bdSPoul-Henning Kamp 	/* Now that we are the child, write out the pid */
94c6262cb6SPawel Jakub Dawidek 	if (pidfile)
95c6262cb6SPawel Jakub Dawidek 		pidfile_write(pfh);
96846be7bdSPoul-Henning Kamp 
97bd06a3ecSMike Barcroft 	execvp(argv[0], argv);
98bd06a3ecSMike Barcroft 
99846be7bdSPoul-Henning Kamp 	/*
100846be7bdSPoul-Henning Kamp 	 * execvp() failed -- unlink pidfile if any, and
101846be7bdSPoul-Henning Kamp 	 * report the error
102846be7bdSPoul-Henning Kamp 	 */
103846be7bdSPoul-Henning Kamp 	errcode = errno; /* Preserve errcode -- unlink may reset it */
104846be7bdSPoul-Henning Kamp 	if (pidfile)
105c6262cb6SPawel Jakub Dawidek 		pidfile_remove(pfh);
106846be7bdSPoul-Henning Kamp 
107bd06a3ecSMike Barcroft 	/* The child is now running, so the exit status doesn't matter. */
108846be7bdSPoul-Henning Kamp 	errc(1, errcode, "%s", argv[0]);
109bd06a3ecSMike Barcroft }
110bd06a3ecSMike Barcroft 
111bd06a3ecSMike Barcroft static void
112bd06a3ecSMike Barcroft usage(void)
113bd06a3ecSMike Barcroft {
114846be7bdSPoul-Henning Kamp 	(void)fprintf(stderr,
115846be7bdSPoul-Henning Kamp 	    "usage: daemon [-cf] [-p pidfile] command arguments ...\n");
116bd06a3ecSMike Barcroft 	exit(1);
117bd06a3ecSMike Barcroft }
118