lib/roken/daemon.c

   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  * 3. 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)
  31 static char sccsid[] = "@(#)daemon.c    8.1 (Berkeley) 6/4/93";
  32 #endif /* LIBC_SCCS and not lint */
  33
  34 #include <config.h>
  35
  36 #ifndef HAVE_DAEMON
  37
  38 #ifdef HAVE_FCNTL_H
  39 #include <fcntl.h>
  40 #endif
  41 #ifdef HAVE_PATHS_H
  42 #include <paths.h>
  43 #endif
  44 #ifdef HAVE_UNISTD_H
  45 #include <unistd.h>
  46 #endif
  47
  48 #include "roken.h"
  49
  50 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
  51 daemon(int nochdir, int noclose)
  52 {
  53     int fd;
  54
  55     switch (fork()) {
  56     case -1:
  57         return (-1);
  58     case 0:
  59         break;
  60     default:
  61         _exit(0);
  62     }
  63
  64     if (setsid() == -1)
  65         return (-1);
  66
  67     if (!nochdir)
  68         chdir("/");
  69
  70     if (!noclose && (fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
  71         dup2(fd, STDIN_FILENO);
  72         dup2(fd, STDOUT_FILENO);
  73         dup2(fd, STDERR_FILENO);
  74         if (fd > 2)
  75             close (fd);
  76     }
  77     return (0);
  78 }
  79
  80 #endif /* HAVE_DAEMON */