40c155ff14
"git push" enhancement allows the receiving end to report not only its own refs but refs in repositories it borrows from via the alternate object store mechanism. By telling the sender that objects reachable from these extra refs are already complete in the receiving end, the number of objects that need to be transfered can be cut down. These entries are sent over the wire with string ".have", instead of the actual names of the refs. This string was chosen so that they are ignored by older programs at the sending end. If we sent some random but valid looking refnames for these entries, "matching refs" rule (triggered when running "git push" without explicit refspecs, where the sender learns what refs the receiver has, and updates only the ones with the names of the refs the sender also has) and "delete missing" rule (triggered when "git push --mirror" is used, where the sender tells the receiver to delete the refs it itself does not have) would try to update/delete them, which is not what we want. This prepares the send-pack (and "push" that runs native protocol) to accept extended existing ref information and make use of it. The ".have" entries are excluded from ref matching rules, and are exempt from deletion rule while pushing with --mirror option, but are still used for pack generation purposes by providing more "bottom" range commits. Signed-off-by: Junio C Hamano <gitster@pobox.com>
//////////////////////////////////////////////////////////////// GIT - the stupid content tracker //////////////////////////////////////////////////////////////// "git" can mean anything, depending on your mood. - random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant. - stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang. - "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room. - "goddamn idiotic truckload of sh*t": when it breaks Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals. Git is an Open Source project covered by the GNU General Public License. It was originally written by Linus Torvalds with help of a group of hackers around the net. It is currently maintained by Junio C Hamano. Please read the file INSTALL for installation instructions. See Documentation/tutorial.txt to get started, then see Documentation/everyday.txt for a useful minimum set of commands, and "man git-commandname" for documentation of each command. CVS users may also want to read Documentation/cvs-migration.txt. Many Git online resources are accessible from http://git.or.cz/ including full documentation and Git related tools. The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org. To subscribe to the list, send an email with just "subscribe git" in the body to majordomo@vger.kernel.org. The mailing list archives are available at http://marc.theaimsgroup.com/?l=git and other archival sites. The messages titled "A note from the maintainer", "What's in git.git (stable)" and "What's cooking in git.git (topics)" and the discussion following them on the mailing list give a good reference for project status, development direction and remaining tasks.