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Date: Wed, 23 Jun 2004 17:05:33 -0400 From: Chris Nelson Subject: [SDL] [Patch] WiseGroup MP-8800 / MP-8866 (PS2 Joystick) In the current cvs version, SDL doesn't handle these Playstation2 controller => USB adapters correctly, in linux. It will always assume that the maximum number of joysticks (2 in the case of the MP-8866, 4 in the case of the 8800) are plugged in. This is bad not only because it allows SDL to exaggerate the number of logical joysticks, but primarily because the joystick axes are mapped incorrectly, all over the place, such that the devices are effectively unusable unless you have the maximum number of joysticks plugged in. My changes to src/joystick/linux/SDL_sysjoystick.c build on another's previous work (which was a special case for this very joystick, actually), and fix both of these problems, as well as making the current code a little more general, to allow for others to more easily drop in code for quirky joysticks such as these. I've tested this code under 2.6.7 as well as 2.4.24... Both work as advertised (provided you load the JOYDEV linux code as a module, otherwise they won't work at all, new code or old, but that's another issue entirely). Though this sounds horribly formal, you have my permission to distribute all of my work on this issue under the LGPL. So there.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 25 Jul 2004 18:31:50 +0000
parents 355632dca928
children f12379c41042
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>Chapter 12. Multi-threaded Programming</H1
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>Table of Contents</B
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><DT
><A
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>SDL_CreateThread</A
>&nbsp;--&nbsp;Creates a new thread of execution that shares its parent's properties.</DT
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>SDL_ThreadID</A
>&nbsp;--&nbsp;Get the 32-bit thread identifier for the current thread.</DT
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>SDL_GetThreadID</A
>&nbsp;--&nbsp;Get the SDL thread ID of a SDL_Thread</DT
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>SDL_WaitThread</A
>&nbsp;--&nbsp;Wait for a thread to finish.</DT
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>SDL_KillThread</A
>&nbsp;--&nbsp;Gracelessly terminates the thread.</DT
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>SDL_CreateMutex</A
>&nbsp;--&nbsp;Create a mutex</DT
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>&nbsp;--&nbsp;Destroy a mutex</DT
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>&nbsp;--&nbsp;Lock a mutex</DT
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>&nbsp;--&nbsp;Creates a new semaphore and assigns an initial value to it.</DT
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>SDL_DestroySemaphore</A
>&nbsp;--&nbsp;Destroys a semaphore that was created by <A
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>&nbsp;--&nbsp;Lock a semaphore and suspend the thread if the semaphore value is zero.</DT
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>&nbsp;--&nbsp;Attempt to lock a semaphore but don't suspend the thread.</DT
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>&nbsp;--&nbsp;Lock a semaphore, but only wait up to a specified maximum time.</DT
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>&nbsp;--&nbsp;Unlock a semaphore.</DT
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>&nbsp;--&nbsp;Return the current value of a semaphore.</DT
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>&nbsp;--&nbsp;Create a condition variable</DT
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>&nbsp;--&nbsp;Destroy a condition variable</DT
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>&nbsp;--&nbsp;Restart a thread wait on a condition variable</DT
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>&nbsp;--&nbsp;Restart all threads waiting on a condition variable</DT
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>SDL_CondWait</A
>&nbsp;--&nbsp;Wait on a condition variable</DT
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>&nbsp;--&nbsp;Wait on a condition variable, with timeout</DT
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>Don't call SDL video/event functions from separate threads</P
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>Don't use any library functions in separate threads</P
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>Don't perform any memory management in separate threads</P
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>Lock global variables which may be accessed by multiple threads</P
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>Never terminate threads, always set a flag and wait for them to quit</P
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>Think very carefully about all possible ways your code may interact</P
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>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
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