[pacman-dev] xdelta status

Xavier shiningxc at gmail.com
Thu Feb 7 08:03:29 EST 2008

I was also wondering about the status of xdelta itself.

 From http://code.google.com/p/xdelta/ :
> Xdelta is a tool and library for differential compression.
> Xdelta release version 3 supports VCDIFF encoding and decoding.
 > This is a BETA release, but almost stable.
 > Supports compressing 64 bit files on Windows, Linux, etc.
> Xdelta 1.1.4 is the last stable release. Xdelta 1.1.0 was released in 1999.

So, the arch package will be updated to xdelta 3 only when it is marked 
stable, right? Since it's almost stable, maybe this could happen in the 
near future. Will this cause any problems on pacman side?

There was also a comparison of both there :
"The only advantages of xdelta3 I see right now is its reduced 
disk-space usage during delta creation, and the possibility of 
completely closing the rather unimportant md5 hole without extra 
patching time/disc-space. That and it seems to be generally a bit 
quicker in patching."

This benchmark was made 8 months ago though, so xdelta3 might be even 
better now.

Also when xdelta 3 is stable, we will have the alternative to use the 
API. It looks like we could simply do a copy / paste of the code() 
function there which is ~100 lines :

Then it's just a matter of using fopen, calling that code function, and 
then fclose.

But while using the API looks cleaner, Dan had several arguments against 
doing it:

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