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 *
21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static const char rcsid[] = "$OpenBSD: pidfile.c,v 1.5 2002/05/26 09:29:02 deraadt Exp $";
36 #endif /* LIBC_SCCS and not lint */
37
38 #include <sys/param.h>
39 #include <errno.h>
40 #include <paths.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <unistd.h>
44 #ifdef __FreeBSD__
45 #include "pidfile.h"
46 #else
47 #include <util.h>
48 #endif
49
50 static char *pidfile_path;
51 static pid_t pidfile_pid;
52
53 static void pidfile_cleanup(void);
54
55 extern char *__progname;
56
57 int
pidfile(const char * basename)58 pidfile(const char *basename)
59 {
60 FILE *f;
61 int save_errno;
62 pid_t pid;
63
64 if (basename == NULL)
65 basename = __progname;
66
67 if (pidfile_path != NULL) {
68 free(pidfile_path);
69 pidfile_path = NULL;
70 }
71
72 /* _PATH_VARRUN includes trailing / */
73 (void) asprintf(&pidfile_path, "%s%s.pid", _PATH_VARRUN, basename);
74 if (pidfile_path == NULL)
75 return (-1);
76
77 if ((f = fopen(pidfile_path, "w")) == NULL) {
78 save_errno = errno;
79 free(pidfile_path);
80 pidfile_path = NULL;
81 errno = save_errno;
82 return (-1);
83 }
84
85 pid = getpid();
86 if (fprintf(f, "%ld\n", (long)pid) <= 0 || fclose(f) != 0) {
87 save_errno = errno;
88 (void) unlink(pidfile_path);
89 free(pidfile_path);
90 pidfile_path = NULL;
91 errno = save_errno;
92 return (-1);
93 }
94
95 pidfile_pid = pid;
96 if (atexit(pidfile_cleanup) < 0) {
97 save_errno = errno;
98 (void) unlink(pidfile_path);
99 free(pidfile_path);
100 pidfile_path = NULL;
101 pidfile_pid = 0;
102 errno = save_errno;
103 return (-1);
104 }
105
106 return (0);
107 }
108
109 static void
pidfile_cleanup(void)110 pidfile_cleanup(void)
111 {
112
113 if (pidfile_path != NULL && pidfile_pid == getpid())
114 (void) unlink(pidfile_path);
115 }
116