1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * 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 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28#include <stdlib.h>
29#include <unistd.h>
30#include <fcntl.h>
31
32int  daemon( int  nochdir, int  noclose )
33{
34   pid_t  pid;
35
36   if ( !nochdir && chdir("/") != 0 )
37       return -1;
38
39   if ( !noclose )
40   {
41     int  fd = open("/dev/null", O_RDWR);
42
43     if ( fd < 0 )
44      return -1;
45
46     if ( dup2( fd, 0 ) < 0 ||
47	  dup2( fd, 1 ) < 0 ||
48          dup2( fd, 2 ) < 0 )
49     {
50       close(fd);
51      return -1;
52     }
53     close(fd);
54  }
55
56   pid = fork();
57   if (pid < 0)
58    return -1;
59
60   if (pid > 0)
61    _exit(0);
62
63   if ( setsid() < 0 )
64     return -1;
65
66   return 0;
67}
68
69