view src/video/os2fslib/SDL_os2fslib.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 e3242177fe4a
children 782fd950bd46 c121d94672cb a1b03ba2fcd0
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

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

#ifndef _SDL_os2fslib_h
#define _SDL_os2fslib_h


// OS2 specific includes
#define INCL_TYPES
#define INCL_DOS
#define INCL_DOSERRORS
#define INCL_DOSPROCESS
#define INCL_WIN
#define INCL_GPI
#include <os2.h>

#include <FSLib.h>

/* Hidden "this" pointer for the video functions */
#define _THIS	SDL_VideoDevice *_this

/* Private display data */
struct SDL_PrivateVideoData
{
  FSLib_VideoMode_p   pAvailableFSLibVideoModes;
  SDL_Rect          **pListModesResult; // Allocated memory to return list of modes for os2fslib_ListModes() API

  FSLib_VideoMode     SrcBufferDesc;    // Description of current source image buffer
  char               *pchSrcBuffer;     // The source image buffer itself
  SDL_Surface        *pSDLSurface;      // The SDL surface describing the buffer
  HMTX                hmtxUseSrcBuffer; // Mutex semaphore to manipulate src buffer
  HWND                hwndFrame, hwndClient;  // Window handle of frame and client
  int                 iPMThreadStatus;  // 0: Not running
                                        // 1: Running
                                        // Other: Not running, had an error
  int                 tidPMThread;      // Thread ID of PM Thread
  int                 fInFocus;         // True if we're in focus!
  int                 iSkipWMMOUSEMOVE; // Number of WM_MOUSEMOVE messages to skip!
  int                 iMouseVisible;    //

  PFNWP               pfnOldFrameProc;  // Old window frame procedure
  int                 bProportionalResize; // 0: No proportional resizing
                                           // 1: Do proportional resizing
  ULONG               ulResizingFlag;   // First resizing flag value
};

/* OS/2 specific backdoor function to be able to set FrameControlFlags of */
/* the SDL window before creating it. */
extern DECLSPEC void SDLCALL SDL_OS2FSLIB_SetFCFToUse(ULONG ulFCF);

#endif /* _SDL_os2fslib_h */