When checking how git-clone behaves when it fails, we stimulate some failures by trying to do a clone from a local repository whose objects have been removed. Because these clones use local optimizations, there's a subtle dependency in how the corruption is handled on the sending side. If upload-pack does not show us the broken refs (which it does not currently), then we see only HEAD (which is itself broken), and clone that as a detached HEAD. When we try to write the ref, we notice that we never got the object and bail. But if upload-pack _does_ show us the broken refs (which it may in a future patch), then we'll realize that HEAD is a symref and just write that. You'd think we'd fail when writing out the refs themselves, but we don't; we do a bulk write and skip the connectivity check because of our --local optimizations. For the non-bare case, we do notice the problem when we try to checkout. But for a bare repository, we unexpectedly complete the clone successfully! At first glance this may seem like a bug. But the whole point of those local optimizations is to give up some safety for speed. If you want to be careful, you should be using "--no-local", which would notice that the pack did not transfer sufficient objects. We could do that in these tests, but part of the point is for them to fail at specific moments (and indeed, we have a later test that checks for transport failure). However, we can make this less subtle and future-proof it against changes on the upload-pack side by just having an explicit detached HEAD in the corrupted repo. Now we'll fail as expected during the ref write if any ref _or_ HEAD is corrupt, whether we're --bare or not. Signed-off-by: Jeff King <peff@peff.net> Reviewed-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
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 version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
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 (read Documentation/SubmittingPatches for instructions on patch submission). 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 https://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (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