Yum-presto (deltarpms) ready for testing.

Michael Schroeder mls at suse.de
Tue Mar 27 10:05:43 UTC 2007


On Mon, Mar 26, 2007 at 04:34:21PM -0400, seth vidal wrote:
> 1. why are you using md5sum and not sha1sums?

It checks if the md5sum of the file matches the sum from the rpm
header.

It works basically like this: The "sequence" tells applydeltarpm
which of the files from the rpm header were used to create the
deltarpm and the order of those files (thus the name "sequence"
in case you wondered). makedeltarpm doesn't use all files to
create the delta, config files and files that have the "verify"
bit off get excluded. If you ask applydeltarpm to check if a
deltarpm can be applied it uses this sequence to verify that all
used files are unchanged, either by just checking the size (the
fast method) or by checking the md5sum (like rpm does).
The fast method makes sense if the updater has a fallback to
fetch the complete rpm if applydeltarpm failes, as in most cases
files are unchanged if the size is the same.

Cheers,
  Michael.

-- 
Michael Schroeder                                   mls at suse.de
SUSE LINUX Products GmbH, GF Markus Rex, HRB 16746 AG Nuernberg
main(_){while(_=~getchar())putchar(~_-1/(~(_|32)/13*2-11)*13);}




More information about the fedora-devel-list mailing list