Mercurial > sdl-ios-xcode
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Date: Wed, 29 Mar 2006 17:26:55 +0200 CEST
From: "Fran���is Revol"
Subject: [SDL] BeOS port fix: PrintScreen key crashing
It seems the latest SDL crashes when someone hits the PrtScrn key in
ZETA (BeOS R6), somewhere it gets a negative value as key code (or a
big unsigned maybe ?), and uses it as an index in the keysym table...
I'll investigate the cause for the negative value, but it's always
better to check for bounds correctly when indexing a table. The
attached diff fixes it.
Fran���is Revol
--
Software Architect
yellowTAB GmbH
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 31 Mar 2006 06:16:20 +0000 |
parents | 355632dca928 |
children | f12379c41042 |
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<HTML ><HEAD ><TITLE >Multi-threaded Programming</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="SDL Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_CDtrack" HREF="sdlcdtrack.html"><LINK REL="NEXT" TITLE="SDL_CreateThread" HREF="sdlcreatethread.html"><META NAME="KEYWORD" CONTENT="threads"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="sdlcdtrack.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlcreatethread.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="THREAD" ></A >Chapter 12. Multi-threaded Programming</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT ><A HREF="sdlcreatethread.html" >SDL_CreateThread</A > -- Creates a new thread of execution that shares its parent's properties.</DT ><DT ><A HREF="sdlthreadid.html" >SDL_ThreadID</A > -- Get the 32-bit thread identifier for the current thread.</DT ><DT ><A HREF="sdlgetthreadid.html" >SDL_GetThreadID</A > -- Get the SDL thread ID of a SDL_Thread</DT ><DT ><A HREF="sdlwaitthread.html" >SDL_WaitThread</A > -- Wait for a thread to finish.</DT ><DT ><A HREF="sdlkillthread.html" >SDL_KillThread</A > -- Gracelessly terminates the thread.</DT ><DT ><A HREF="sdlcreatemutex.html" >SDL_CreateMutex</A > -- Create a mutex</DT ><DT ><A HREF="sdldestroymutex.html" >SDL_DestroyMutex</A > -- Destroy a mutex</DT ><DT ><A HREF="sdlmutexp.html" >SDL_mutexP</A > -- Lock a mutex</DT ><DT ><A HREF="sdlmutexv.html" >SDL_mutexV</A > -- Unlock a mutex</DT ><DT ><A HREF="sdlcreatesemaphore.html" >SDL_CreateSemaphore</A > -- Creates a new semaphore and assigns an initial value to it.</DT ><DT ><A HREF="sdldestroysemaphore.html" >SDL_DestroySemaphore</A > -- Destroys a semaphore that was created by <A HREF="sdlcreatesemaphore.html" >SDL_CreateSemaphore</A >.</DT ><DT ><A HREF="sdlsemwait.html" >SDL_SemWait</A > -- Lock a semaphore and suspend the thread if the semaphore value is zero.</DT ><DT ><A HREF="sdlsemtrywait.html" >SDL_SemTryWait</A > -- Attempt to lock a semaphore but don't suspend the thread.</DT ><DT ><A HREF="sdlsemwaittimeout.html" >SDL_SemWaitTimeout</A > -- Lock a semaphore, but only wait up to a specified maximum time.</DT ><DT ><A HREF="sdlsempost.html" >SDL_SemPost</A > -- Unlock a semaphore.</DT ><DT ><A HREF="sdlsemvalue.html" >SDL_SemValue</A > -- Return the current value of a semaphore.</DT ><DT ><A HREF="sdlcreatecond.html" >SDL_CreateCond</A > -- Create a condition variable</DT ><DT ><A HREF="sdldestroycond.html" >SDL_DestroyCond</A > -- Destroy a condition variable</DT ><DT ><A HREF="sdlcondsignal.html" >SDL_CondSignal</A > -- Restart a thread wait on a condition variable</DT ><DT ><A HREF="sdlcondbroadcast.html" >SDL_CondBroadcast</A > -- Restart all threads waiting on a condition variable</DT ><DT ><A HREF="sdlcondwait.html" >SDL_CondWait</A > -- Wait on a condition variable</DT ><DT ><A HREF="sdlcondwaittimeout.html" >SDL_CondWaitTimeout</A > -- Wait on a condition variable, with timeout</DT ></DL ></DIV ><P >SDL provides functions for creating threads, mutexes, semphores and condition variables.</P ><P >In general, you must be very aware of concurrency and data integrity issues when writing multi-threaded programs. Some good guidelines include: <P ></P ><UL ><LI ><P >Don't call SDL video/event functions from separate threads</P ></LI ><LI ><P >Don't use any library functions in separate threads</P ></LI ><LI ><P >Don't perform any memory management in separate threads</P ></LI ><LI ><P >Lock global variables which may be accessed by multiple threads</P ></LI ><LI ><P >Never terminate threads, always set a flag and wait for them to quit</P ></LI ><LI ><P >Think very carefully about all possible ways your code may interact</P ></LI ></UL ></P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B >SDL's threading is not implemented on MacOS, due to that lack of preemptive thread support (MacOS X dos nt suffer from this problem)</P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdlcdtrack.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlcreatethread.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_CDtrack</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_CreateThread</TD ></TR ></TABLE ></DIV ></BODY ></HTML >