mirror of
https://github.com/git/git.git
synced 2026-01-22 14:57:18 +09:00
09c9957cf7
Send-pack deadlocks in two ways when pack-object dies early (for example, because there is some repo corruption). The first deadlock happens with the smart push protocol (--stateless-rpc). After the initial rev-exchange, the remote is waiting for the pack data to arrive, and the sideband demuxer at the local side continues trying to stream data from the remote repository until it gets EOF. Meanwhile, send-pack (in function pack_objects()) has noticed that pack-objects did not produce output and died. Back in send_pack(), it now tries to clean up the sideband demuxer using finish_async(). The demuxer, however, waits for the remote end to close down, the remote waits for pack data, and the reason that it still waits is that send-pack forgot to close the outgoing channel. Add the missing close() in pack_objects(). The second deadlock happens in a similar constellation when the sideband demuxer runs in a forked process (rather than in a thread). Again, the remote end waits for pack data to arrive, the sideband demuxer waits for the remote to shut down, and send-pack (in the regular clean-up) waits for the demuxer to terminate. This time, the send-pack parent process closes the writable end of the outgoing channel (in start_command() that spawned pack-objects) so that after the death of the pack-objects process all writable ends should have been closed and the remote repo should see EOF. This does not happen, however, because when the sideband demuxer was forked earlier, it also inherited a writable end; it remains open and keeps the remote repo from seeing EOF. To break this deadlock, close the writable end in the demuxer. Analyzed-by: Jeff King <peff@peff.net> Signed-off-by: Johannes Sixt <j6t@kdbg.org> 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/gittutorial.txt to get started, then see
Documentation/everyday.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).
Many Git online resources are accessible from http://git-scm.com/
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.