1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)daemon.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "namespace.h" 41 #include <errno.h> 42 #include <fcntl.h> 43 #include <paths.h> 44 #include <signal.h> 45 #include <unistd.h> 46 #include "un-namespace.h" 47 48 int 49 daemon(nochdir, noclose) 50 int nochdir, noclose; 51 { 52 struct sigaction osa, sa; 53 int fd; 54 pid_t newgrp; 55 int oerrno; 56 int osa_ok; 57 58 /* A SIGHUP may be thrown when the parent exits below. */ 59 sigemptyset(&sa.sa_mask); 60 sa.sa_handler = SIG_IGN; 61 sa.sa_flags = 0; 62 osa_ok = _sigaction(SIGHUP, &sa, &osa); 63 64 switch (fork()) { 65 case -1: 66 return (-1); 67 case 0: 68 break; 69 default: 70 _exit(0); 71 } 72 73 newgrp = setsid(); 74 oerrno = errno; 75 if (osa_ok != -1) 76 _sigaction(SIGHUP, &osa, NULL); 77 78 if (newgrp == -1) { 79 errno = oerrno; 80 return (-1); 81 } 82 83 if (!nochdir) 84 (void)chdir("/"); 85 86 if (!noclose && (fd = _open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { 87 (void)_dup2(fd, STDIN_FILENO); 88 (void)_dup2(fd, STDOUT_FILENO); 89 (void)_dup2(fd, STDERR_FILENO); 90 if (fd > 2) 91 (void)_close(fd); 92 } 93 return (0); 94 } 95