Re: [Lzip-bug] lzlib: Question/Remarks about some API Signatures

[Antonio Diaz Diaz]

Hello Tino,

Tino Lange wrote:
> 1) shouldn't
> Function: int LZ_compress_write   ( void * const encoder, uint8_t * const 
> buffer, const int size )
> Function: int LZ_decompress_write ( void * const decoder, uint8_t * const 
> buffer, const int size )
> be changed to use a const buffer (as it's really only read from it), i.e:

Done. Thanks for reporting this.


> 2) Why does the function family
> long long LZ_compress_data_position ( void * const encoder )
> return a signed value? Wouldn't ~0ULL for the error be enough?

A signed value is consistent with the rest of the library functions. All 
of them return -1 on error.


> Also there should IMHO be some remark in the documentation that at least
> for the compress functions all the numbers are correct only after flush
> (if it would be working :-) ) or finish has been called. Before there
> can be even 0 or 6 as result although quite large amounts of data have
> already been sucessfully compressed with write/read. This might be
> confusing (at least it was for me yesterday ... :-) )

Lzlib compresses on read, so you can write a lot of data and 
LZ_compress_data_position will still return 0. 
(LZ_compress_member_position returns 6, the size of the member header). 
I'll explain this in the documentation.

BTW, I have already fixed the flush problem. I'll release a corrected 
version tomorrow or so. (Sorry, but there is no repository for lzlib). 
In the meantime you can try calling LZ_compress_sync_flush 4 consecutive 
times.


Regards,
Antonio.