src/signal.cxx

   1 /*
   2  * inoclam - Inotify+ClamAV virus scanner
   3  * Copyright (C) 2007, 2008, 2009 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 version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19 #include <libdaemon/dlog.h>
  20 #include <signal.h>
  21
  22 #include "signal.hxx"
  23
  24 /**
  25  * Global variable used to determine if the program should halt. Will it ever halt? Only Alan Turing knows.
  26  * @see handle_signal()
  27  */
  28 int exit_now;
  29
  30 /**
  31  * Signal handler for SIGKILL
  32  * @param sig signal to handle.
  33  */
  34 void handle_sigkill(int sig)
  35 {
  36         if (sig == SIGKILL) {
  37                 exit_now = 1;
  38                 daemon_log(LOG_INFO, "SIGKILL Caught ; preparing to exit");
  39         }
  40 }
  41
  42 /**
  43  * Signal handler for SIGQUIT
  44  * @param sig signal to handle.
  45  */
  46 void handle_sigquit(int sig)
  47 {
  48         if (sig == SIGQUIT) {
  49                 exit_now = 1;
  50                 daemon_log(LOG_INFO, "SIGQUIT Caught ; preparing to exit");
  51         }
  52 }
  53
  54 /**
  55  * Signal handler for SIGINT
  56  * @param sig signal to handle.
  57  */
  58 void handle_sigint(int sig)
  59 {
  60         if (sig == SIGINT) {
  61                 exit_now = 1;
  62                 daemon_log(LOG_INFO, "SIGINT Caught ; preparing to exit");
  63         }
  64 }
  65
  66 /**
  67  *  installs signal handlers (mostly SIG_IGN)
  68  */
  69 void install_signal_handlers()
  70 {
  71
  72         int i;
  73
  74         for (i = 0; i < 32; i++) {
  75                 if (i != SIGCHLD && i != SIGQUIT && i != SIGINT && i != SIGKILL) {
  76                         signal(i, SIG_IGN);
  77                 }
  78         }
  79
  80         signal(SIGKILL, handle_sigkill);
  81         signal(SIGQUIT, handle_sigquit);
  82         signal(SIGINT, handle_sigint);
  83 }