Mercurial > sdl-ios-xcode
view docs/index.html @ 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 | c6a447c98584 |
children |
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<!DOCTYPE HTML PUBLIC "-//Norman Walsh//DTD DocBook HTML 1.0//EN"> <HTML> <HEAD><TITLE>Simple DirectMedia Layer Introduction</TITLE></HEAD> <BODY BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000"> <DIV CLASS="NAVHEADER"> <HR ALIGN="LEFT" WIDTH="100%"> </DIV> <DIV CLASS="PREFACE"> <H2><A NAME="AEN8">Simple DirectMedia Layer Introduction</A></H2> <P> This library is designed to make it easy to write games that run on many different platforms using the various native high-performance media interfaces, (for video, audio, etc) and presenting a single source-code level API to your application. This is a fairly low level API, but using this, completely portable applications can be written with a great deal of flexibility. </P><P> An introduction to SDL can be found online at: <A HREF="http://www.libsdl.org/intro.php" TARGET="_top"> http://www.libsdl.org/intro.php</A> </P><P> Tutorials on a variety of topics can be found online at: <A HREF="http://www.libsdl.org/tutorials.php" TARGET="_top"> http://www.libsdl.org/tutorials.php</A> </P><P> Documentation in Wiki form can be found online at: <A HREF="http://www.libsdl.org/cgi/docwiki.cgi/" TARGET="_top"> http://www.libsdl.org/cgi/docwiki.cgi/</A> </P><P> Enjoy! </P><P> Sam Lantinga <TT CLASS="EMAIL"><<A HREF="mailto:slouken@libsdl.org"><A HREF="mailto:slouken@libsdl.org" TARGET="_top" >slouken@libsdl.org</A></A>></TT> </P> <P> <br><br><HR> <H1>Table of Contents</H1> <UL> <LI><A HREF="html/index.html">Full Table of Contents</A></LI> <LI><A HREF="html/guide.html">The SDL Guide</A></LI> <LI><A HREF="html/reference.html">The SDL Reference</A></LI> <UL> <LI><A HREF="html/general.html">Initialization</A></LI> <LI><A HREF="html/video.html">Video</A></LI> <LI><A HREF="html/wm.html">Window Manager</A></LI> <LI><A HREF="html/event.html">Event Handling</A></LI> <LI><A HREF="html/joystick.html">Joystick</A></LI> <LI><A HREF="html/audio.html">Audio</A></LI> <LI><A HREF="html/cdrom.html">CDROM</A></LI> <LI><A HREF="html/thread.html">Threads</A></LI> <LI><A HREF="html/time.html">Timers</A></LI> </UL> </UL> </DIV ></BODY ></HTML >