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/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. 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.
* 4. 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)daemon.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <unistd.h>
#include <sys/stat.h>
#include <device-nrs.h>
#include <not-cancel.h>
int
daemon (int nochdir, int noclose)
{
int fd;
switch (__fork ())
{
case -1:
return -1;
case 0:
break;
default:
_exit (0);
}
if (__setsid () == -1)
return -1;
if (!nochdir)
(void) __chdir ("/");
if (!noclose)
{
struct __stat64_t64 st;
fd = __open_nocancel (_PATH_DEVNULL, O_RDWR, 0);
if (fd != -1 && __glibc_likely (__fstat64_time64 (fd, &st) == 0))
{
if (__builtin_expect (S_ISCHR (st.st_mode), 1) != 0
#if defined DEV_NULL_MAJOR && defined DEV_NULL_MINOR
&& (st.st_rdev == makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR))
#endif
)
{
(void) __dup2 (fd, STDIN_FILENO);
(void) __dup2 (fd, STDOUT_FILENO);
(void) __dup2 (fd, STDERR_FILENO);
if (fd > 2)
(void) __close (fd);
}
else
{
/* We must set an errno value since no function call
actually failed. */
__close_nocancel_nostatus (fd);
__set_errno (ENODEV);
return -1;
}
}
else
{
__close_nocancel_nostatus (fd);
return -1;
}
}
return 0;
}
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