view include/SDL.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 4ed717f9e509
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
*/

/* Main include header for the SDL library */

#ifndef _SDL_H
#define _SDL_H

#include "SDL_main.h"
#include "SDL_stdinc.h"
#include "SDL_audio.h"
#include "SDL_cdrom.h"
#include "SDL_cpuinfo.h"
#include "SDL_endian.h"
#include "SDL_error.h"
#include "SDL_events.h"
#include "SDL_loadso.h"
#include "SDL_mutex.h"
#include "SDL_rwops.h"
#include "SDL_thread.h"
#include "SDL_timer.h"
#include "SDL_video.h"
#include "SDL_version.h"

#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif

/* As of version 0.5, SDL is loaded dynamically into the application */

/* These are the flags which may be passed to SDL_Init() -- you should
   specify the subsystems which you will be using in your application.
*/
#define	SDL_INIT_TIMER		0x00000001
#define SDL_INIT_AUDIO		0x00000010
#define SDL_INIT_VIDEO		0x00000020
#define SDL_INIT_CDROM		0x00000100
#define SDL_INIT_JOYSTICK	0x00000200
#define SDL_INIT_NOPARACHUTE	0x00100000	/* Don't catch fatal signals */
#define SDL_INIT_EVENTTHREAD	0x01000000	/* Not supported on all OS's */
#define SDL_INIT_EVERYTHING	0x0000FFFF

/* This function loads the SDL dynamically linked library and initializes 
 * the subsystems specified by 'flags' (and those satisfying dependencies)
 * Unless the SDL_INIT_NOPARACHUTE flag is set, it will install cleanup
 * signal handlers for some commonly ignored fatal signals (like SIGSEGV)
 */
extern DECLSPEC int SDLCALL SDL_Init(Uint32 flags);

/* This function initializes specific SDL subsystems */
extern DECLSPEC int SDLCALL SDL_InitSubSystem(Uint32 flags);

/* This function cleans up specific SDL subsystems */
extern DECLSPEC void SDLCALL SDL_QuitSubSystem(Uint32 flags);

/* This function returns mask of the specified subsystems which have
   been initialized.
   If 'flags' is 0, it returns a mask of all initialized subsystems.
*/
extern DECLSPEC Uint32 SDLCALL SDL_WasInit(Uint32 flags);

/* This function cleans up all initialized subsystems and unloads the
 * dynamically linked library.  You should call it upon all exit conditions.
 */
extern DECLSPEC void SDLCALL SDL_Quit(void);

/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"

#endif /* _SDL_H */