sdl

SDL_quit.c (5132B)

---

 /*
   Simple DirectMedia Layer
   Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
 
   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
   arising from the use of this software.
 
   Permission is granted to anyone to use this software for any purpose,
   including commercial applications, and to alter it and redistribute it
   freely, subject to the following restrictions:
 
   1. The origin of this software must not be misrepresented; you must not
      claim that you wrote the original software. If you use this software
      in a product, an acknowledgment in the product documentation would be
      appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must not be
      misrepresented as being the original software.
   3. This notice may not be removed or altered from any source distribution.
 */
 #include "../SDL_internal.h"
 
 #include "SDL_hints.h"
 
 /* General quit handling code for SDL */
 
 #ifdef HAVE_SIGNAL_H
 #include <signal.h>
 #endif
 
 #include "SDL_events.h"
 #include "SDL_events_c.h"
 
 #if defined(HAVE_SIGNAL_H) || defined(HAVE_SIGACTION)
 #define HAVE_SIGNAL_SUPPORT 1
 #endif
 
 #ifdef HAVE_SIGNAL_SUPPORT
 static SDL_bool disable_signals = SDL_FALSE;
 static SDL_bool send_quit_pending = SDL_FALSE;
 
 #ifdef SDL_BACKGROUNDING_SIGNAL
 static SDL_bool send_backgrounding_pending = SDL_FALSE;
 #endif
 
 #ifdef SDL_FOREGROUNDING_SIGNAL
 static SDL_bool send_foregrounding_pending = SDL_FALSE;
 #endif
 
 static void
 SDL_HandleSIG(int sig)
 {
     /* Reset the signal handler */
     signal(sig, SDL_HandleSIG);
 
     /* Send a quit event next time the event loop pumps. */
     /* We can't send it in signal handler; malloc() might be interrupted! */
     if ((sig == SIGINT) || (sig == SIGTERM)) {
         send_quit_pending = SDL_TRUE;
     }
 
     #ifdef SDL_BACKGROUNDING_SIGNAL
     else if (sig == SDL_BACKGROUNDING_SIGNAL) {
         send_backgrounding_pending = SDL_TRUE;
     }
     #endif
 
     #ifdef SDL_FOREGROUNDING_SIGNAL
     else if (sig == SDL_FOREGROUNDING_SIGNAL) {
         send_foregrounding_pending = SDL_TRUE;
     }
     #endif
 }
 
 static void
 SDL_EventSignal_Init(const int sig)
 {
 #ifdef HAVE_SIGACTION
     struct sigaction action;
 
     sigaction(sig, NULL, &action);
 #ifdef HAVE_SA_SIGACTION
     if ( action.sa_handler == SIG_DFL && (void (*)(int))action.sa_sigaction == SIG_DFL ) {
 #else
     if ( action.sa_handler == SIG_DFL ) {
 #endif
         action.sa_handler = SDL_HandleSIG;
         sigaction(sig, &action, NULL);
     }
 #elif HAVE_SIGNAL_H
     void (*ohandler) (int) = signal(sig, SDL_HandleSIG);
     if (ohandler != SIG_DFL) {
         signal(sig, ohandler);
     }
 #endif
 }
 
 static void
 SDL_EventSignal_Quit(const int sig)
 {
 #ifdef HAVE_SIGACTION
     struct sigaction action;
     sigaction(sig, NULL, &action);
     if ( action.sa_handler == SDL_HandleSIG ) {
         action.sa_handler = SIG_DFL;
         sigaction(sig, &action, NULL);
     }
 #elif HAVE_SIGNAL_H
     void (*ohandler) (int) = signal(sig, SIG_DFL);
     if (ohandler != SDL_HandleSIG) {
         signal(sig, ohandler);
     }
 #endif /* HAVE_SIGNAL_H */
 }
 
 /* Public functions */
 static int
 SDL_QuitInit_Internal(void)
 {
     /* Both SIGINT and SIGTERM are translated into quit interrupts */
     /* and SDL can be built to simulate iOS/Android semantics with arbitrary signals. */
     SDL_EventSignal_Init(SIGINT);
     SDL_EventSignal_Init(SIGTERM);
 
     #ifdef SDL_BACKGROUNDING_SIGNAL
     SDL_EventSignal_Init(SDL_BACKGROUNDING_SIGNAL);
     #endif
 
     #ifdef SDL_FOREGROUNDING_SIGNAL
     SDL_EventSignal_Init(SDL_FOREGROUNDING_SIGNAL);
     #endif
 
     /* That's it! */
     return 0;
 }
 
 static void
 SDL_QuitQuit_Internal(void)
 {
     SDL_EventSignal_Quit(SIGINT);
     SDL_EventSignal_Quit(SIGTERM);
 
     #ifdef SDL_BACKGROUNDING_SIGNAL
     SDL_EventSignal_Quit(SDL_BACKGROUNDING_SIGNAL);
     #endif
 
     #ifdef SDL_FOREGROUNDING_SIGNAL
     SDL_EventSignal_Quit(SDL_FOREGROUNDING_SIGNAL);
     #endif
 }
 #endif
 
 int
 SDL_QuitInit(void)
 {
 #ifdef HAVE_SIGNAL_SUPPORT
     if (!SDL_GetHintBoolean(SDL_HINT_NO_SIGNAL_HANDLERS, SDL_FALSE)) {
         return SDL_QuitInit_Internal();
     }
 #endif
     return 0;
 }
 
 void
 SDL_QuitQuit(void)
 {
 #ifdef HAVE_SIGNAL_SUPPORT
     if (!disable_signals) {
         SDL_QuitQuit_Internal();
     }
 #endif
 }
 
 void
 SDL_SendPendingSignalEvents(void)
 {
 #ifdef HAVE_SIGNAL_SUPPORT
     if (send_quit_pending) {
         SDL_SendQuit();
         SDL_assert(!send_quit_pending);
     }
 
     #ifdef SDL_BACKGROUNDING_SIGNAL
     if (send_backgrounding_pending) {
         send_backgrounding_pending = SDL_FALSE;
         SDL_OnApplicationWillResignActive();
     }
     #endif
 
     #ifdef SDL_FOREGROUNDING_SIGNAL
     if (send_foregrounding_pending) {
         send_foregrounding_pending = SDL_FALSE;
         SDL_OnApplicationDidBecomeActive();
     }
     #endif
 #endif
 }
 
 /* This function returns 1 if it's okay to close the application window */
 int
 SDL_SendQuit(void)
 {
 #ifdef HAVE_SIGNAL_SUPPORT
     send_quit_pending = SDL_FALSE;
 #endif
     return SDL_SendAppEvent(SDL_QUIT);
 }
 
 /* vi: set ts=4 sw=4 expandtab: */