src/sig.c

   1 /*======================================================================*
   2  * Copyright (C) 2008 Light Weight Event System                         *
   3  * All rights reserved.                                                 *
   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., 51 Franklin Street, Fifth Floor,                   *
  18  * Boston, MA 02110-1301 USA.                                           *
  19  *======================================================================*/
  20
  21 #include "config.h"
  22
  23 #include "sig.h"
  24
  25 #include "log.h"
  26 #include "perror.h"
  27
  28 #include <signal.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31
  32 volatile int gbl_done = 0;
  33 volatile int gbl_rotate = 0;
  34 volatile int gbl_rotate_log = 0;
  35
  36 static void terminate_signal_handler(int signo)
  37 {
  38   gbl_done = signo;
  39 }
  40
  41 static void rotate_signal_handler(int signo)
  42 {
  43   (void)signo; /* appease -Wall -Werror */
  44   gbl_rotate = 1;
  45 }
  46
  47 static void rotate_log_signal_handler(int signo)
  48 {
  49   (void)signo; /* appease -Wall -Werror */
  50   gbl_rotate_log = 1;
  51 }
  52
  53 static void install(int signo, void (*handler)(int signo))
  54 {
  55   struct sigaction sigact;
  56
  57   memset(&sigact, 0, sizeof(sigact));
  58
  59   sigact.sa_handler = handler;
  60
  61   sigemptyset(&sigact.sa_mask);
  62   sigact.sa_flags = 0;
  63
  64   if ( sigaction(signo, &sigact, NULL) < 0 )
  65     {
  66       PERROR("sigaction");
  67       exit(EXIT_FAILURE);
  68     }
  69 }
  70
  71 void install_signal_handlers()
  72 {
  73   struct sigaction sigact;
  74
  75   /* Any of these signals shuts us down. */
  76   LOG_PROG("Installing termination signal handlers.\n");
  77
  78   install(SIGINT, terminate_signal_handler);
  79   install(SIGQUIT, terminate_signal_handler);
  80   install(SIGTERM, terminate_signal_handler);
  81
  82   memset(&sigact, 0, sizeof(sigact));
  83   sigact.sa_handler = SIG_IGN;
  84
  85   sigemptyset(&sigact.sa_mask);
  86   sigact.sa_flags = 0;
  87
  88   if ( sigaction(SIGPIPE, &sigact, NULL) < 0 )
  89     {
  90       PERROR("sigaction");
  91       exit(EXIT_FAILURE);
  92     }
  93 }
  94
  95 void install_rotate_signal_handlers()
  96 {
  97   LOG_PROG("Installing rotate signal handlers.\n");
  98
  99   /* This one triggers a journal rotate. */
 100   install(SIGHUP, rotate_signal_handler);
 101
 102   /* This one triggers a log rotate. */
 103   install(SIGUSR1, rotate_log_signal_handler);
 104 }