Fw: wavread.m does not parse Wave files correctly

[John W. Eaton]

On  5-Feb-2009, Frederick_Umminger at playstation.sony.com wrote:

| FYI, a reference to the Wave file spec can be found at 
| 
| http://www-mmsp.ece.mcgill.ca/Documents/AudioFormats/WAVE/Docs/riffmci.pdf
| 
| 
| ----- Forwarded by Frederick Umminger/R&D/SCEA on 02/05/2009 03:12 PM 
| -----
| 
| Frederick Umminger/R&D/SCEA 
| 02/05/2009 03:11 PM
| 
| To
| bug at octave.org
| cc
| 
| Subject
| wavread.m does not parse Wave files correctly
| 
| 
| 
| 
| 
| Bug: wavread.m does not parse Wave files correctly.
| 
| wavread.m incorrectly bounds the search for format and data chunks to 
| search only the nearest 256 bytes after the current file position. This is 
| not guaranteed by the RIFF spec and can easily be false if the Wave file 
| contains extra chunks beyond the format and data chunks. 
| 
| wavread.m also ignores the chunk structure and incorrectly looks for chunk 
| ids in illegal positions.
| 
| Sincerely,
|    Frederick Umminger
| 
| 
| Here is an improved version. 

Please post a context diff relative to the version you started with.
We don't generally replace functions with completely new versions, as
that could wipe out other changes that have been made.

It would also be helpful if you would follow the coding style of the
rest of Octave.

Thanks,

jwe