src/events/SDL_quit.c
author Sam Lantinga <slouken@libsdl.org>
Tue, 30 Jan 2018 18:12:25 -0800
changeset 11840 4d52395a8dba
parent 11839 971881e55d61
child 12503 806492103856
permissions -rw-r--r--
Fixed building on platforms without __sighandler_t
     1 /*
     2   Simple DirectMedia Layer
     3   Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
     4 
     5   This software is provided 'as-is', without any express or implied
     6   warranty.  In no event will the authors be held liable for any damages
     7   arising from the use of this software.
     8 
     9   Permission is granted to anyone to use this software for any purpose,
    10   including commercial applications, and to alter it and redistribute it
    11   freely, subject to the following restrictions:
    12 
    13   1. The origin of this software must not be misrepresented; you must not
    14      claim that you wrote the original software. If you use this software
    15      in a product, an acknowledgment in the product documentation would be
    16      appreciated but is not required.
    17   2. Altered source versions must be plainly marked as such, and must not be
    18      misrepresented as being the original software.
    19   3. This notice may not be removed or altered from any source distribution.
    20 */
    21 #include "../SDL_internal.h"
    22 #include "SDL_hints.h"
    23 #include "SDL_assert.h"
    24 
    25 /* General quit handling code for SDL */
    26 
    27 #ifdef HAVE_SIGNAL_H
    28 #include <signal.h>
    29 #endif
    30 
    31 #include "SDL_events.h"
    32 #include "SDL_events_c.h"
    33 
    34 static SDL_bool disable_signals = SDL_FALSE;
    35 static SDL_bool send_quit_pending = SDL_FALSE;
    36 
    37 #ifdef HAVE_SIGNAL_H
    38 static void
    39 SDL_HandleSIG(int sig)
    40 {
    41     /* Reset the signal handler */
    42     signal(sig, SDL_HandleSIG);
    43 
    44     /* Send a quit event next time the event loop pumps. */
    45     /* We can't send it in signal handler; malloc() might be interrupted! */
    46     send_quit_pending = SDL_TRUE;
    47 }
    48 #endif /* HAVE_SIGNAL_H */
    49 
    50 /* Public functions */
    51 static int
    52 SDL_QuitInit_Internal(void)
    53 {
    54 #ifdef HAVE_SIGACTION
    55     struct sigaction action;
    56     sigaction(SIGINT, NULL, &action);
    57 #ifdef HAVE_SA_SIGACTION
    58     if ( action.sa_handler == SIG_DFL && (void (*)(int))action.sa_sigaction == SIG_DFL ) {
    59 #else
    60     if ( action.sa_handler == SIG_DFL ) {
    61 #endif
    62         action.sa_handler = SDL_HandleSIG;
    63         sigaction(SIGINT, &action, NULL);
    64     }
    65     sigaction(SIGTERM, NULL, &action);
    66 
    67 #ifdef HAVE_SA_SIGACTION
    68     if ( action.sa_handler == SIG_DFL && (void (*)(int))action.sa_sigaction == SIG_DFL ) {
    69 #else
    70     if ( action.sa_handler == SIG_DFL ) {
    71 #endif
    72         action.sa_handler = SDL_HandleSIG;
    73         sigaction(SIGTERM, &action, NULL);
    74     }
    75 #elif HAVE_SIGNAL_H
    76     void (*ohandler) (int);
    77 
    78     /* Both SIGINT and SIGTERM are translated into quit interrupts */
    79     ohandler = signal(SIGINT, SDL_HandleSIG);
    80     if (ohandler != SIG_DFL)
    81         signal(SIGINT, ohandler);
    82     ohandler = signal(SIGTERM, SDL_HandleSIG);
    83     if (ohandler != SIG_DFL)
    84         signal(SIGTERM, ohandler);
    85 #endif /* HAVE_SIGNAL_H */
    86 
    87     /* That's it! */
    88     return 0;
    89 }
    90 
    91 int
    92 SDL_QuitInit(void)
    93 {
    94     if (!SDL_GetHintBoolean(SDL_HINT_NO_SIGNAL_HANDLERS, SDL_FALSE)) {
    95         return SDL_QuitInit_Internal();
    96     }
    97     return 0;
    98 }
    99 
   100 static void
   101 SDL_QuitQuit_Internal(void)
   102 {
   103 #ifdef HAVE_SIGACTION
   104     struct sigaction action;
   105     sigaction(SIGINT, NULL, &action);
   106     if ( action.sa_handler == SDL_HandleSIG ) {
   107         action.sa_handler = SIG_DFL;
   108         sigaction(SIGINT, &action, NULL);
   109     }
   110     sigaction(SIGTERM, NULL, &action);
   111     if ( action.sa_handler == SDL_HandleSIG ) {
   112         action.sa_handler = SIG_DFL;
   113         sigaction(SIGTERM, &action, NULL);
   114     }
   115 #elif HAVE_SIGNAL_H
   116     void (*ohandler) (int);
   117 
   118     ohandler = signal(SIGINT, SIG_DFL);
   119     if (ohandler != SDL_HandleSIG)
   120         signal(SIGINT, ohandler);
   121     ohandler = signal(SIGTERM, SIG_DFL);
   122     if (ohandler != SDL_HandleSIG)
   123         signal(SIGTERM, ohandler);
   124 #endif /* HAVE_SIGNAL_H */
   125 }
   126 
   127 void
   128 SDL_QuitQuit(void)
   129 {
   130     if (!disable_signals) {
   131         SDL_QuitQuit_Internal();
   132     }
   133 }
   134 
   135 /* This function returns 1 if it's okay to close the application window */
   136 int
   137 SDL_SendQuit(void)
   138 {
   139     send_quit_pending = SDL_FALSE;
   140     return SDL_SendAppEvent(SDL_QUIT);
   141 }
   142 
   143 void
   144 SDL_SendPendingQuit(void)
   145 {
   146     if (send_quit_pending) {
   147         SDL_SendQuit();
   148         SDL_assert(!send_quit_pending);
   149     }
   150 }
   151 
   152 /* vi: set ts=4 sw=4 expandtab: */