view src/SDL_error_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 e25445333ccf
children 782fd950bd46 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"

/* This file defines a structure that carries language-independent
   error messages
*/

#ifndef _SDL_error_c_h
#define _SDL_error_c_h

#define ERR_MAX_STRLEN	128
#define ERR_MAX_ARGS	5

typedef struct SDL_error {
	/* This is a numeric value corresponding to the current error */
	int error;

	/* This is a key used to index into a language hashtable containing
	   internationalized versions of the SDL error messages.  If the key
	   is not in the hashtable, or no hashtable is available, the key is
	   used directly as an error message format string.
	*/
	char key[ERR_MAX_STRLEN];

	/* These are the arguments for the error functions */
	int argc;
	union {
		void *value_ptr;
#if 0	/* What is a character anyway?  (UNICODE issues) */
		unsigned char value_c;
#endif
		int value_i;
		double value_f;
		char buf[ERR_MAX_STRLEN];
	} args[ERR_MAX_ARGS];
} SDL_error;

#endif /* _SDL_error_c_h */