xref: /freebsd/contrib/pf/pflogd/pidfile.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
1 /*	$FreeBSD$ */
2 /*	$OpenBSD: pidfile.c,v 1.5 2002/05/26 09:29:02 deraadt Exp $	*/
3 /*	$NetBSD: pidfile.c,v 1.4 2001/02/19 22:43:42 cgd Exp $	*/
4 
5 /*-
6  * Copyright (c) 1999 The NetBSD Foundation, Inc.
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Jason R. Thorpe.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *        This product includes software developed by the NetBSD
23  *        Foundation, Inc. and its contributors.
24  * 4. Neither the name of The NetBSD Foundation nor the names of its
25  *    contributors may be used to endorse or promote products derived
26  *    from this software without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGE.
39  */
40 
41 #if defined(LIBC_SCCS) && !defined(lint)
42 static const char rcsid[] = "$OpenBSD: pidfile.c,v 1.5 2002/05/26 09:29:02 deraadt Exp $";
43 #endif /* LIBC_SCCS and not lint */
44 
45 #include <sys/param.h>
46 #include <errno.h>
47 #include <paths.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <unistd.h>
51 #ifdef __FreeBSD__
52 #include "pidfile.h"
53 #else
54 #include <util.h>
55 #endif
56 
57 static char *pidfile_path;
58 static pid_t pidfile_pid;
59 
60 static void pidfile_cleanup(void);
61 
62 extern char *__progname;
63 
64 int
65 pidfile(const char *basename)
66 {
67 	FILE *f;
68 	int save_errno;
69 	pid_t pid;
70 
71 	if (basename == NULL)
72 		basename = __progname;
73 
74 	if (pidfile_path != NULL) {
75 		free(pidfile_path);
76 		pidfile_path = NULL;
77 	}
78 
79 	/* _PATH_VARRUN includes trailing / */
80 	(void) asprintf(&pidfile_path, "%s%s.pid", _PATH_VARRUN, basename);
81 	if (pidfile_path == NULL)
82 		return (-1);
83 
84 	if ((f = fopen(pidfile_path, "w")) == NULL) {
85 		save_errno = errno;
86 		free(pidfile_path);
87 		pidfile_path = NULL;
88 		errno = save_errno;
89 		return (-1);
90 	}
91 
92 	pid = getpid();
93 	if (fprintf(f, "%ld\n", (long)pid) <= 0 || fclose(f) != 0) {
94 		save_errno = errno;
95 		(void) unlink(pidfile_path);
96 		free(pidfile_path);
97 		pidfile_path = NULL;
98 		errno = save_errno;
99 		return (-1);
100 	}
101 
102 	pidfile_pid = pid;
103 	if (atexit(pidfile_cleanup) < 0) {
104 		save_errno = errno;
105 		(void) unlink(pidfile_path);
106 		free(pidfile_path);
107 		pidfile_path = NULL;
108 		pidfile_pid = 0;
109 		errno = save_errno;
110 		return (-1);
111 	}
112 
113 	return (0);
114 }
115 
116 static void
117 pidfile_cleanup(void)
118 {
119 
120 	if (pidfile_path != NULL && pidfile_pid == getpid())
121 		(void) unlink(pidfile_path);
122 }
123