view src/events/SDL_events_c.h @ 4158:96ce26f24b01 SDL-1.2

Date: Sun, 7 Sep 2008 15:17:00 +0200 From: c2woody@gmx.net Subject: [SDL] SDL 1.2 doube free/pointer zeroing missing Hello, this is about a crash/debug breakage for the current SDL 1.2 source tree (today's svn checkout, same problem in 1.2.13 and before as far as relevant). In some places memory is free()d but the associated pointer is not zeroed, leading to for example double free()s. For me this happened because SDL_StopEventThread() was executed twice (during restart of the subsystems), once for the close down in SDL_VideoQuit() and once at the startup, right at the beginning of SDL_StartEventLoop(). Thus the code SDL_DestroyMutex(SDL_EventQ.lock); (see SDL_events.c) was called twice and executed the SDL_free(mutex); twice as well, leading to a crash (msvc 64bit for which it was noticed). I've tried to check all other occurrences of SDL_free and similar code in msvc, see the attached patch (udiff against revision 4082). Non-windows only codepaths have neither been checked nor touched. Comments/ideas welcome. Attached patch: NULLifies some pointers after they have been free()d.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 12 Nov 2008 17:23:40 +0000
parents 97d0966f4bf7
children 782fd950bd46 c121d94672cb a1b03ba2fcd0
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Useful functions and variables from SDL_events.c */
#include "SDL_events.h"

/* Start and stop the event processing loop */
extern int SDL_StartEventLoop(Uint32 flags);
extern void SDL_StopEventLoop(void);
extern void SDL_QuitInterrupt(void);

extern void SDL_Lock_EventThread(void);
extern void SDL_Unlock_EventThread(void);
extern Uint32 SDL_EventThreadID(void);

/* Event handler init routines */
extern int  SDL_AppActiveInit(void);
extern int  SDL_KeyboardInit(void);
extern int  SDL_MouseInit(void);
extern int  SDL_QuitInit(void);

/* Event handler quit routines */
extern void SDL_AppActiveQuit(void);
extern void SDL_KeyboardQuit(void);
extern void SDL_MouseQuit(void);
extern void SDL_QuitQuit(void);

/* The event filter function */
extern SDL_EventFilter SDL_EventOK;

/* The array of event processing states */
extern Uint8 SDL_ProcessEvents[SDL_NUMEVENTS];

/* Internal event queueing functions
   (from SDL_active.c, SDL_mouse.c, SDL_keyboard.c, SDL_quit.c, SDL_events.c)
 */
extern int SDL_PrivateAppActive(Uint8 gain, Uint8 state);
extern int SDL_PrivateMouseMotion(Uint8 buttonstate, int relative,
						Sint16 x, Sint16 y);
extern int SDL_PrivateMouseButton(Uint8 state, Uint8 button,Sint16 x,Sint16 y);
extern int SDL_PrivateKeyboard(Uint8 state, SDL_keysym *key);
extern int SDL_PrivateResize(int w, int h);
extern int SDL_PrivateExpose(void);
extern int SDL_PrivateQuit(void);
extern int SDL_PrivateSysWMEvent(SDL_SysWMmsg *message);

/* Used by the activity event handler to remove mouse focus */
extern void SDL_ResetMouse(void);

/* Used by the activity event handler to remove keyboard focus */
extern void SDL_ResetKeyboard(void);

/* Used by the event loop to queue pending keyboard repeat events */
extern void SDL_CheckKeyRepeat(void);

/* Used by the OS keyboard code to detect whether or not to do UNICODE */
#ifndef DEFAULT_UNICODE_TRANSLATION
#define DEFAULT_UNICODE_TRANSLATION 0	/* Default off because of overhead */
#endif
extern int SDL_TranslateUNICODE;