[MERGE] readv access to pack files

[Robert Collins]

This patch adds enough API support to do readv style access to pack
files. Needless to say this is a requirement for a pack based
repository :).

I think this is safe to come in as it does not change any of the
existing pack API's in an incompatible way, nor the reader code at all.

-Rob
-- 
GPG key available at: <http://www.robertcollins.net/keys.txt>.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: pack-readv.patch
Type: text/x-patch
Size: 16141 bytes
Desc: not available
Url : https://lists.ubuntu.com/archives/bazaar/attachments/20070802/6c288771/attachment-0001.bin 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
Url : https://lists.ubuntu.com/archives/bazaar/attachments/20070802/6c288771/attachment-0001.pgp