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.

Wish list for the 1.3 development branch:
http://bugzilla.libsdl.org/

 * Add mousewheel events (new unified event architecture?)
 * DirectInput joystick support needs to be implemented
 * Be able to enumerate and select available audio and video drivers
 * Fullscreen video mode support for Mac OS X
 * Explicit vertical retrace wait (maybe separate from SDL_Flip?)
 * Shaped windows, windows without borders
 * Multiple windows, multiple display support
 * SDL_INIT_EVENTTHREAD on Windows and MacOS?
 * Add a timestamp to events
 * Add audio input API
 * Add hardware accelerated scaled blit
 * Add hardware accelerated alpha blits
 * Redesign blitting architecture to allow blit plugins

In the jump from 1.2 to 1.3, we should change the SDL_Rect members to
int and evaluate all the rest of the datatypes.  This is the only place
we should do it though, since the 1.2 series should not break binary
compatibility in this way.

Requests:
 * PCM and CDROM volume control (deprecated, but possible)