mdw@git.distorted.org.uk Git - tripe/blob - util.c

   1 /* -*-c-*-
   2  *
   3  * $Id: util.c,v 1.2 2001/02/22 09:07:08 mdw Exp $
   4  *
   5  * Utilities for the client and the server
   6  *
   7  * (c) 2001 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Trivial IP Encryption (TrIPE).
  13  *
  14  * TrIPE is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * TrIPE is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with TrIPE; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: util.c,v $
  32  * Revision 1.2  2001/02/22 09:07:08  mdw
  33  * Separate detach-from-terminal code into a separate function.
  34  *
  35  * Revision 1.1  2001/02/03 20:26:37  mdw
  36  * Initial checkin.
  37  *
  38  */
  39
  40 /*----- Header files ------------------------------------------------------*/
  41
  42 #include <errno.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46
  47 #include <sys/types.h>
  48 #include <unistd.h>
  49 #include <fcntl.h>
  50
  51 #include "util.h"
  52
  53 #include <sys/ioctl.h>
  54
  55 /*----- Main code ---------------------------------------------------------*/
  56
  57 /* --- @u_detach@ --- *
  58  *
  59  * Arguments:   ---
  60  *
  61  * Returns:     ---
  62  *
  63  * Use:         Detaches from the current terminal and ensures it can never
  64  *              acquire a new one.  Calls @fork@.
  65  */
  66
  67 void u_detach(void)
  68 {
  69 #ifdef TIOCNOTTY
  70   {
  71     int fd;
  72     if ((fd = open("/dev/tty", O_RDONLY)) >= 0) {
  73       ioctl(fd, TIOCNOTTY);
  74       close(fd);
  75     }
  76   }
  77 #endif
  78   setsid();
  79   if (fork() > 0)
  80     _exit(0);
  81 }
  82
  83 /* --- @u_daemon@ --- *
  84  *
  85  * Arguments:   ---
  86  *
  87  * Returns:     Zero if OK, nonzero on failure.
  88  *
  89  * Use:         Becomes a daemon.
  90  */
  91
  92 int u_daemon(void)
  93 {
  94   pid_t kid;
  95
  96   if ((kid = fork()) < 0)
  97     return (-1);
  98   if (kid)
  99     _exit(0);
 100   u_detach();
 101   return (0);
 102 }
 103
 104 /*----- That's all, folks -------------------------------------------------*/