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)
35static 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
50static char *pidfile_path;
51static pid_t pidfile_pid;
52
53static void pidfile_cleanup(void);
54
55extern char *__progname;
56
57int
58pidfile(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
109static void
110pidfile_cleanup(void)
111{
112
113	if (pidfile_path != NULL && pidfile_pid == getpid())
114		(void) unlink(pidfile_path);
115}
116