Re: [PATCH][UPDATED] support for xz compression format

[Szymon Janc]

Dnia wtorek 16 luty 2010 o 22:11:50 address@hidden napisał(a):

> Since gzip format allows decompression in pipeline mode, it's a
> virtual certainty that nothing from the footer is required for
> processing.
> 
> And of course this is true of the xz format as well.  I quote from the
> documentation:

The only reason for checking footer is to get uncompressed data size to keep 
grub_file_read() happy.

Possible sollutions to avoid this:
- add size field in stream header and break compatibility with upstream xz/gz, 
will require forking upstream compression tools or create special tool for 
crafting upstream created files
  
- increase size while consuming blocks (possible with xz, don't know if with 
gz), this leaves possibility to get grub_file_read() unhappy

- try to guess uncompressed data size based on compressed size

-- 
Szymon K. Janc
address@hidden // GG: 1383435