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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1990, 1993 The Regents of the University of California.
* Copyright (c) 2017 Mariusz Zaborski <oshogbo@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "namespace.h"
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <stdlib.h>
#include <signal.h>
#include <unistd.h>
#include "un-namespace.h"
#include "libc_private.h"
int
daemonfd(int chdirfd, int nullfd)
{
struct sigaction osa, sa;
pid_t newgrp;
int oerrno;
int osa_ok;
/* A SIGHUP may be thrown when the parent exits below. */
sigemptyset(&sa.sa_mask);
sa.sa_handler = SIG_IGN;
sa.sa_flags = 0;
osa_ok = __libc_sigaction(SIGHUP, &sa, &osa);
switch (fork()) {
case -1:
return (-1);
case 0:
break;
default:
/*
* A fine point: _exit(0), not exit(0), to avoid triggering
* atexit(3) processing
*/
_exit(0);
}
newgrp = setsid();
oerrno = errno;
if (osa_ok != -1)
__libc_sigaction(SIGHUP, &osa, NULL);
if (newgrp == -1) {
errno = oerrno;
return (-1);
}
if (chdirfd != -1)
(void)fchdir(chdirfd);
if (nullfd != -1) {
(void)_dup2(nullfd, STDIN_FILENO);
(void)_dup2(nullfd, STDOUT_FILENO);
(void)_dup2(nullfd, STDERR_FILENO);
}
return (0);
}
int
daemon(int nochdir, int noclose)
{
int chdirfd, nullfd, ret;
if (!noclose)
nullfd = _open(_PATH_DEVNULL, O_RDWR, 0);
else
nullfd = -1;
if (!nochdir)
chdirfd = _open("/", O_EXEC);
else
chdirfd = -1;
ret = daemonfd(chdirfd, nullfd);
if (chdirfd != -1)
_close(chdirfd);
if (nullfd > 2)
_close(nullfd);
return (ret);
}
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