src/SDL_fatal.c

   1 /*
   2     SDL - Simple DirectMedia Layer
   3     Copyright (C) 1997-2006 Sam Lantinga
   4
   5     This library is free software; you can redistribute it and/or
   6     modify it under the terms of the GNU Lesser General Public
   7     License as published by the Free Software Foundation; either
   8     version 2.1 of the License, or (at your option) any later version.
   9
  10     This library 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 GNU
  13     Lesser General Public License for more details.
  14
  15     You should have received a copy of the GNU Lesser General Public
  16     License along with this library; if not, write to the Free Software
  17     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18
  19     Sam Lantinga
  20     slouken@libsdl.org
  21 */
  22 #include "SDL_config.h"
  23
  24 /* General fatal signal handling code for SDL */
  25
  26 #ifdef HAVE_SIGNAL_H
  27
  28 #include <signal.h>
  29
  30 #include "SDL.h"
  31 #include "SDL_fatal.h"
  32
  33 /* This installs some signal handlers for the more common fatal signals,
  34    so that if the programmer is lazy, the app doesn't die so horribly if
  35    the program crashes.
  36 */
  37
  38 static void SDL_Parachute(int sig)
  39 {
  40         signal(sig, SIG_DFL);
  41         SDL_Quit();
  42         raise(sig);
  43 }
  44
  45 static int SDL_fatal_signals[] = {
  46         SIGSEGV,
  47 #ifdef SIGBUS
  48         SIGBUS,
  49 #endif
  50 #ifdef SIGFPE
  51         SIGFPE,
  52 #endif
  53 #ifdef SIGQUIT
  54         SIGQUIT,
  55 #endif
  56         0
  57 };
  58
  59 void SDL_InstallParachute(void)
  60 {
  61         /* Set a handler for any fatal signal not already handled */
  62         int i;
  63 #ifdef HAVE_SIGACTION
  64         struct sigaction action;
  65
  66         for ( i=0; SDL_fatal_signals[i]; ++i ) {
  67                 sigaction(SDL_fatal_signals[i], NULL, &action);
  68                 if ( action.sa_handler == SIG_DFL ) {
  69                         action.sa_handler = SDL_Parachute;
  70                         sigaction(SDL_fatal_signals[i], &action, NULL);
  71                 }
  72         }
  73 #ifdef SIGALRM
  74         /* Set SIGALRM to be ignored -- necessary on Solaris */
  75         sigaction(SIGALRM, NULL, &action);
  76         if ( action.sa_handler == SIG_DFL ) {
  77                 action.sa_handler = SIG_IGN;
  78                 sigaction(SIGALRM, &action, NULL);
  79         }
  80 #endif
  81 #else
  82         void (*ohandler)(int);
  83
  84         for ( i=0; SDL_fatal_signals[i]; ++i ) {
  85                 ohandler = signal(SDL_fatal_signals[i], SDL_Parachute);
  86                 if ( ohandler != SIG_DFL ) {
  87                         signal(SDL_fatal_signals[i], ohandler);
  88                 }
  89         }
  90 #endif /* HAVE_SIGACTION */
  91         return;
  92 }
  93
  94 void SDL_UninstallParachute(void)
  95 {
  96         /* Remove a handler for any fatal signal handled */
  97         int i;
  98 #ifdef HAVE_SIGACTION
  99         struct sigaction action;
 100
 101         for ( i=0; SDL_fatal_signals[i]; ++i ) {
 102                 sigaction(SDL_fatal_signals[i], NULL, &action);
 103                 if ( action.sa_handler == SDL_Parachute ) {
 104                         action.sa_handler = SIG_DFL;
 105                         sigaction(SDL_fatal_signals[i], &action, NULL);
 106                 }
 107         }
 108 #else
 109         void (*ohandler)(int);
 110
 111         for ( i=0; SDL_fatal_signals[i]; ++i ) {
 112                 ohandler = signal(SDL_fatal_signals[i], SIG_DFL);
 113                 if ( ohandler != SDL_Parachute ) {
 114                         signal(SDL_fatal_signals[i], ohandler);
 115                 }
 116         }
 117 #endif /* HAVE_SIGACTION */
 118 }
 119
 120 #else
 121
 122 /* No signals on this platform, nothing to do.. */
 123
 124 void SDL_InstallParachute(void)
 125 {
 126         return;
 127 }
 128
 129 void SDL_UninstallParachute(void)
 130 {
 131         return;
 132 }
 133
 134 #endif /* HAVE_SIGNAL_H */