signal.cxx

   1 /*
   2  * inoclam - Inotify+ClamAV virus scanner
   3  * Copyright (C) 2007 Vermont Department of Taxes
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  * Contributor(s):
  20  *   Tom Cort <tom.cort@state.vt.us>
  21  */
  22
  23 #include <libdaemon/dlog.h>
  24 #include <signal.h>
  25
  26 #include "signal.hxx"
  27
  28 /**
  29  * Global variable used to determine if the program should halt. Will it ever halt? Only Alan Turing knows.
  30  * @see handle_signal()
  31  */
  32 int exit_now;
  33
  34 /**
  35  * Signal handler for SIGKILL
  36  * @param sig signal to handle.
  37  */
  38 void handle_sigkill(int sig)
  39 {
  40         if (sig == SIGKILL) {
  41                 exit_now = 1;
  42                 daemon_log(LOG_INFO, "(%s:%u) SIGKILL Caught ; preparing to exit", __FILE__, __LINE__);
  43         }
  44 }
  45
  46 /**
  47  * Signal handler for SIGQUIT
  48  * @param sig signal to handle.
  49  */
  50 void handle_sigquit(int sig)
  51 {
  52         if (sig == SIGQUIT) {
  53                 exit_now = 1;
  54                 daemon_log(LOG_INFO, "(%s:%u) SIGQUIT Caught ; preparing to exit", __FILE__, __LINE__);
  55         }
  56 }
  57
  58 /**
  59  * Signal handler for SIGINT
  60  * @param sig signal to handle.
  61  */
  62 void handle_sigint(int sig)
  63 {
  64         if (sig == SIGINT) {
  65                 exit_now = 1;
  66                 daemon_log(LOG_INFO, "(%s:%u) SIGINT Caught ; preparing to exit", __FILE__, __LINE__);
  67         }
  68 }
  69
  70 /**
  71  *  installs signal handlers (mostly SIG_IGN)
  72  */
  73 void install_signal_handlers()
  74 {
  75
  76         int i;
  77
  78         for (i = 0; i < 32; i++) {
  79                 if (i != SIGCHLD && i != SIGQUIT && i != SIGINT && i != SIGKILL) {
  80                         signal(i, SIG_IGN);
  81                 }
  82         }
  83
  84         signal(SIGKILL, handle_sigkill);
  85         signal(SIGQUIT, handle_sigquit);
  86         signal(SIGINT, handle_sigint);
  87 }