Since 633a53179e (fetch test: avoid use of "VAR= cmd" with a shell function, 2019-12-26), t5552.5 (do not send "have" with ancestors of commits that server ACKed) fails when run with GIT_TEST_PROTOCOL_VERSION=2. The cause: The progression of "have"s sent in negotiation depends on whether we are using a stateless RPC based transport or a stateful bidirectional one (see for example 44d8dc54e7, "Fix potential local deadlock during fetch-pack", 2011-03-29). In protocol v2, all transports are stateless transports, while in protocol v0, transports such as local access and ssh are stateful. In stateful transports, the number of "have"s to send multiplies by two each round until we reach PIPESAFE_FLUSH (that is, 32), and then it increases by PIPESAFE_FLUSH each round. In stateless transport, the count multiplies by two each round until we reach LARGE_FLUSH (which is 16384) and then multiplies by 1.1 each round after that. Moreover, in stateful transports, as fetch-pack.c explains: We keep one window "ahead" of the other side, and will wait for an ACK only on the next one. This affects t5552.5 because it looks for "have"s from the negotiator that appear in that second window. With protocol version 2, the second window never arrives, and the test fails. Until 633a53179e (2019-12-26), a previous test in the same file contained GIT_TEST_PROTOCOL_VERSION= trace_fetch client origin to_fetch In many common shells (e.g. bash when run as "sh"), the setting of GIT_TEST_PROTOCOL_VERSION to the empty string lasts beyond the intended duration of the trace_fetch invocation. This causes it to override the GIT_TEST_PROTOCOL_VERSION setting that was passed in to the test during the remainder of the test script, so t5552.5 never got run using protocol v2 on those shells, regardless of the GIT_TEST_PROTOCOL_VERSION setting from the environment. 633a53179e fixed that, revealing the failing test. Signed-off-by: Jonathan Nieder <jrnieder@gmail.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