[openal] [WIP] AL_EXT_MSADPCM in OpenAL Soft

[Chris Robinson]

On 03/05/2014 05:57 AM, Ethan Lee wrote:
> Looks great to me! It certainly looks a lot nicer than my solution...
>
> But, currently getting an odd segfault in Convert_ALshort_ALmsadpcm,
> seems to happen at the Conv_ALshort_ALshort line. Couldn't figure it
> out, so I've got a test case over here if anyone wants to look at it:
>
> http://www.flibitijibibo.com/testCaseMSADPCM.tar.bz2

Oops, I wasn't allocating enough temp space in the decoder and encoder 
functions, causing it to overrun the buffer. Fixed now. I also 
implemented optimized methods for ALshort<->ADPCM conversions to avoid 
the temp buffer.