[Zlib-devel] stored-block size limit?

[Mark Adler]

On Tuesday, April 9, 2002, at 10:13  AM, Jean-loup Gailly wrote:
> Ok. Can you suggest specific patches, to both the text and the code?

I have sent you patches to add two functions, deflateBound() and 
compressBound(), and to correct the comments in zlib.h.

> That's indeed a bug. I'll look into it unless you can send patches for 
> this one too.

My recommendation for now is to document the behavior, thereby 
transforming the bug into a feature.  :-)

If you want to fix it, my other suggestion was to force memLevel to be 
no greater than windowBits - 6 in deflateInit2().  This circumvents the 
bug, though it would have some impact on compression compared to the 
unforced settings.

	if (memLevel > windowBits - 6)
		memLevel = windowBits - 6;

It would be harder to fix this without forcing memLevel.  An alternative 
might be to force windowBits instead, but keep two different 
windowBits.  One to define a window memory that's large enough to keep 
the data around to decide on a stored block, and the other to limit the 
distances to the windowBits provided by the user.

mark