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 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 110 pidfile_cleanup(void) 111 { 112 113 if (pidfile_path != NULL && pidfile_pid == getpid()) 114 (void) unlink(pidfile_path); 115 } 116