2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1990, 1993 The Regents of the University of California.
5 * Copyright (c) 2017 Mariusz Zaborski <oshogbo@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 #include <sys/cdefs.h>
34 __SCCSID("@(#)daemon.c 8.1 (Berkeley) 6/4/93");
35 #include "namespace.h"
42 #include "un-namespace.h"
43 #include "libc_private.h"
46 daemonfd(int chdirfd, int nullfd)
48 struct sigaction osa, sa;
53 /* A SIGHUP may be thrown when the parent exits below. */
54 sigemptyset(&sa.sa_mask);
55 sa.sa_handler = SIG_IGN;
57 osa_ok = __libc_sigaction(SIGHUP, &sa, &osa);
66 * A fine point: _exit(0), not exit(0), to avoid triggering
67 * atexit(3) processing
75 __libc_sigaction(SIGHUP, &osa, NULL);
83 (void)fchdir(chdirfd);
86 (void)_dup2(nullfd, STDIN_FILENO);
87 (void)_dup2(nullfd, STDOUT_FILENO);
88 (void)_dup2(nullfd, STDERR_FILENO);
94 daemon(int nochdir, int noclose)
96 int chdirfd, nullfd, ret;
99 nullfd = _open(_PATH_DEVNULL, O_RDWR, 0);
104 chdirfd = _open("/", O_EXEC);
108 ret = daemonfd(chdirfd, nullfd);