Teach the connection logic to tell a serve that it understands protocol
v1. This is done in 2 different ways for the builtin transports, both
of which ultimately set 'GIT_PROTOCOL' to 'version=1' on the server.
1. git://
A normal request to git-daemon is structured as
"command path/to/repo\0host=..\0" and due to a bug introduced in
49ba83fb6 (Add virtualization support to git-daemon, 2006-09-19) we
aren't able to place any extra arguments (separated by NULs) besides
the host otherwise the parsing of those arguments would enter an
infinite loop. This bug was fixed in 73bb33a94 (daemon: Strictly
parse the "extra arg" part of the command, 2009-06-04) but a check
was put in place to disallow extra arguments so that new clients
wouldn't trigger this bug in older servers.
In order to get around this limitation git-daemon was taught to
recognize additional request arguments hidden behind a second
NUL byte. Requests can then be structured like:
"command path/to/repo\0host=..\0\0version=1\0key=value\0".
git-daemon can then parse out the extra arguments and set
'GIT_PROTOCOL' accordingly.
By placing these extra arguments behind a second NUL byte we can
skirt around both the infinite loop bug in 49ba83fb6 (Add
virtualization support to git-daemon, 2006-09-19) as well as the
explicit disallowing of extra arguments introduced in 73bb33a94
(daemon: Strictly parse the "extra arg" part of the command,
2009-06-04) because both of these versions of git-daemon check for a
single NUL byte after the host argument before terminating the
argument parsing.
2. ssh://, file://
Set 'GIT_PROTOCOL' environment variable with the desired protocol
version. With the file:// transport, 'GIT_PROTOCOL' can be set
explicitly in the locally running git-upload-pack or git-receive-pack
processes. With the ssh:// transport and OpenSSH compliant ssh
programs, 'GIT_PROTOCOL' can be sent across ssh by using '-o
SendEnv=GIT_PROTOCOL' and having the server whitelist this
environment variable.
Signed-off-by: Brandon Williams <bmwill@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-.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 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