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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)daemon.c 8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33
34#include <errno.h>
35#include <fcntl.h>
36#include <paths.h>
37#include <unistd.h>
38#include <sys/stat.h>
39
40#include <device-nrs.h>
41#include <not-cancel.h>
42
43int
44daemon (int nochdir, int noclose)
45{
46 int fd;
47
48 switch (__fork ())
49 {
50 case -1:
51 return -1;
52
53 case 0:
54 break;
55
56 default:
57 _exit (0);
58 }
59
60 if (__setsid () == -1)
61 return -1;
62
63 if (!nochdir)
64 (void) __chdir ("/");
65
66 if (!noclose)
67 {
68 struct __stat64_t64 st;
69
70 fd = __open_nocancel (_PATH_DEVNULL, O_RDWR, 0);
71 if (fd != -1 && __glibc_likely (__fstat64_time64 (fd, &st) == 0))
72 {
73 if (__builtin_expect (S_ISCHR (st.st_mode), 1) != 0
74#if defined DEV_NULL_MAJOR && defined DEV_NULL_MINOR
75 && (st.st_rdev == makedev (DEV_NULL_MAJOR, DEV_NULL_MINOR))
76#endif
77 )
78 {
79 (void) __dup2 (fd, STDIN_FILENO);
80 (void) __dup2 (fd, STDOUT_FILENO);
81 (void) __dup2 (fd, STDERR_FILENO);
82 if (fd > 2)
83 (void) __close (fd);
84 }
85 else
86 {
87 /* We must set an errno value since no function call
88 actually failed. */
89 __close_nocancel_nostatus (fd);
90 __set_errno (ENODEV);
91 return -1;
92 }
93 }
94 else
95 {
96 __close_nocancel_nostatus (fd);
97 return -1;
98 }
99 }
100
101 return 0;
102}
103