Documentation/gitrepository-layout.txt - jrn/git - Git at Google

 gitrepository-layout(5)
 =======================

 NAME
 ----
 gitrepository-layout - Git Repository Layout

 SYNOPSIS
 --------
 $GIT_DIR/*

 DESCRIPTION
 -----------

 You may find these things in your git repository (`.git`
 directory for a repository associated with your working tree, or
 `<project>.git` directory for a public 'bare' repository. It is
 also possible to have a working tree where `.git` is a plain
 ascii file containing `gitdir: <path>`, i.e. the path to the
 real git repository).

 objects::
 	Object store associated with this repository.  Usually
 	an object store is self sufficient (i.e. all the objects
 	that are referred to by an object found in it are also
 	found in it), but there are couple of ways to violate
 	it.
 +
 . You could populate the repository by running a commit walker
 without `-a` option.  Depending on which options are given, you
 could have only commit objects without associated blobs and
 trees this way, for example.  A repository with this kind of
 incomplete object store is not suitable to be published to the
 outside world but sometimes useful for private repository.
 . You also could have an incomplete but locally usable repository
 by cloning shallowly.  See linkgit:git-clone[1].
 . You can be using `objects/info/alternates` mechanism, or
 `$GIT_ALTERNATE_OBJECT_DIRECTORIES` mechanism to 'borrow'
 objects from other object stores.  A repository with this kind
 of incomplete object store is not suitable to be published for
 use with dumb transports but otherwise is OK as long as
 `objects/info/alternates` points at the right object stores
 it borrows from.

 objects/[0-9a-f][0-9a-f]::
 	Traditionally, each object is stored in its own file.
 	They are split into 256 subdirectories using the first
 	two letters from its object name to keep the number of
 	directory entries `objects` directory itself needs to
 	hold.  Objects found here are often called 'unpacked'
 	(or 'loose') objects.

 objects/pack::
 	Packs (files that store many object in compressed form,
 	along with index files to allow them to be randomly
 	accessed) are found in this directory.

 objects/info::
 	Additional information about the object store is
 	recorded in this directory.

 objects/info/packs::
 	This file is to help dumb transports discover what packs
 	are available in this object store.  Whenever a pack is
 	added or removed, `git update-server-info` should be run
 	to keep this file up-to-date if the repository is
 	published for dumb transports.  `git repack` does this
 	by default.

 objects/info/alternates::
 	This file records paths to alternate object stores that
 	this object store borrows objects from, one pathname per
 	line. Note that not only native Git tools use it locally,
 	but the HTTP fetcher also tries to use it remotely; this
 	will usually work if you have relative paths (relative
 	to the object database, not to the repository!) in your
 	alternates file, but it will not work if you use absolute
 	paths unless the absolute path in filesystem and web URL
 	is the same. See also 'objects/info/http-alternates'.

 objects/info/http-alternates::
 	This file records URLs to alternate object stores that
 	this object store borrows objects from, to be used when
 	the repository is fetched over HTTP.

 refs::
 	References are stored in subdirectories of this
 	directory.  The `git prune` command knows to keep
 	objects reachable from refs found in this directory and
 	its subdirectories.

 refs/heads/`name`::
 	records tip-of-the-tree commit objects of branch `name`

 refs/tags/`name`::
 	records any object name (not necessarily a commit
 	object, or a tag object that points at a commit object).

 refs/remotes/`name`::
 	records tip-of-the-tree commit objects of branches copied
 	from a remote repository.

 packed-refs::
 	records the same information as refs/heads/, refs/tags/,
 	and friends record in a more efficient way.  See
 	linkgit:git-pack-refs[1].

 HEAD::
 	A symref (see glossary) to the `refs/heads/` namespace
 	describing the currently active branch.  It does not mean
 	much if the repository is not associated with any working tree
 	(i.e. a 'bare' repository), but a valid git repository
 	*must* have the HEAD file; some porcelains may use it to
 	guess the designated "default" branch of the repository
 	(usually 'master').  It is legal if the named branch
 	'name' does not (yet) exist.  In some legacy setups, it is
 	a symbolic link instead of a symref that points at the current
 	branch.
 +
 HEAD can also record a specific commit directly, instead of
 being a symref to point at the current branch.  Such a state
 is often called 'detached HEAD', and almost all commands work
 identically as normal.  See linkgit:git-checkout[1] for
 details.

 branches::
 	A slightly deprecated way to store shorthands to be used
 	to specify URL to `git fetch`, `git pull` and `git push`
 	commands is to store a file in `branches/<name>` and
 	give 'name' to these commands in place of 'repository'
 	argument.

 hooks::
 	Hooks are customization scripts used by various git
 	commands.  A handful of sample hooks are installed when
 	`git init` is run, but all of them are disabled by
 	default.  To enable, they need to be made executable.
 	Read linkgit:githooks[5][hooks] for more details about
 	each hook.

 index::
 	The current index file for the repository.  It is
 	usually not found in a bare repository.

 info::
 	Additional information about the repository is recorded
 	in this directory.

 info/refs::
 	This file helps dumb transports discover what refs are
 	available in this repository.  If the repository is
 	published for dumb transports, this file should be
 	regenerated by `git update-server-info` every time a tag
 	or branch is created or modified.  This is normally done
 	from the `hooks/update` hook, which is run by the
 	`git-receive-pack` command when you `git push` into the
 	repository.

 info/grafts::
 	This file records fake commit ancestry information, to
 	pretend the set of parents a commit has is different
 	from how the commit was actually created.  One record
 	per line describes a commit and its fake parents by
 	listing their 40-byte hexadecimal object names separated
 	by a space and terminated by a newline.

 info/exclude::
 	This file, by convention among Porcelains, stores the
 	exclude pattern list. `.gitignore` is the per-directory
 	ignore file.  `git status`, `git add`, `git rm` and `git
 	clean` look at it but the core git commands do not look
 	at it.  See also: linkgit:gitignore[5].

 remotes::
 	Stores shorthands to be used to give URL and default
 	refnames to interact with remote repository to `git
 	fetch`, `git pull` and `git push` commands.

 logs::
 	Records of changes made to refs are stored in this
 	directory.  See the documentation on git-update-ref
 	for more information.

 logs/refs/heads/`name`::
 	Records all changes made to the branch tip named `name`.

 logs/refs/tags/`name`::
 	Records all changes made to the tag named `name`.

 shallow::
 	This is similar to `info/grafts` but is internally used
 	and maintained by shallow clone mechanism.  See `--depth`
 	option to linkgit:git-clone[1] and linkgit:git-fetch[1].

 SEE ALSO
 --------
 linkgit:git-init[1],
 linkgit:git-clone[1],
 linkgit:git-fetch[1],
 linkgit:git-pack-refs[1],
 linkgit:git-gc[1],
 linkgit:git-checkout[1],
 linkgit:gitglossary[7],
 link:user-manual.html[The Git User's Manual]

 GIT
 ---
 Part of the linkgit:git[1] suite.
	gitrepository-layout(5)
	=======================

	NAME
	----
	gitrepository-layout - Git Repository Layout

	SYNOPSIS
	--------
	$GIT_DIR/*

	DESCRIPTION
	-----------

	You may find these things in your git repository (`.git`
	directory for a repository associated with your working tree, or
	`<project>.git` directory for a public 'bare' repository. It is
	also possible to have a working tree where `.git` is a plain
	ascii file containing `gitdir: <path>`, i.e. the path to the
	real git repository).

	objects::
	Object store associated with this repository. Usually
	an object store is self sufficient (i.e. all the objects
	that are referred to by an object found in it are also
	found in it), but there are couple of ways to violate
	it.
	+
	. You could populate the repository by running a commit walker
	without `-a` option. Depending on which options are given, you
	could have only commit objects without associated blobs and
	trees this way, for example. A repository with this kind of
	incomplete object store is not suitable to be published to the
	outside world but sometimes useful for private repository.
	. You also could have an incomplete but locally usable repository
	by cloning shallowly. See linkgit:git-clone[1].
	. You can be using `objects/info/alternates` mechanism, or
	`$GIT_ALTERNATE_OBJECT_DIRECTORIES` mechanism to 'borrow'
	objects from other object stores. A repository with this kind
	of incomplete object store is not suitable to be published for
	use with dumb transports but otherwise is OK as long as
	`objects/info/alternates` points at the right object stores
	it borrows from.

	objects/[0-9a-f][0-9a-f]::
	Traditionally, each object is stored in its own file.
	They are split into 256 subdirectories using the first
	two letters from its object name to keep the number of
	directory entries `objects` directory itself needs to
	hold. Objects found here are often called 'unpacked'
	(or 'loose') objects.

	objects/pack::
	Packs (files that store many object in compressed form,
	along with index files to allow them to be randomly
	accessed) are found in this directory.

	objects/info::
	Additional information about the object store is
	recorded in this directory.

	objects/info/packs::
	This file is to help dumb transports discover what packs
	are available in this object store. Whenever a pack is
	added or removed, `git update-server-info` should be run
	to keep this file up-to-date if the repository is
	published for dumb transports. `git repack` does this
	by default.

	objects/info/alternates::
	This file records paths to alternate object stores that
	this object store borrows objects from, one pathname per
	line. Note that not only native Git tools use it locally,
	but the HTTP fetcher also tries to use it remotely; this
	will usually work if you have relative paths (relative
	to the object database, not to the repository!) in your
	alternates file, but it will not work if you use absolute
	paths unless the absolute path in filesystem and web URL
	is the same. See also 'objects/info/http-alternates'.

	objects/info/http-alternates::
	This file records URLs to alternate object stores that
	this object store borrows objects from, to be used when
	the repository is fetched over HTTP.

	refs::
	References are stored in subdirectories of this
	directory. The `git prune` command knows to keep
	objects reachable from refs found in this directory and
	its subdirectories.

	refs/heads/`name`::
	records tip-of-the-tree commit objects of branch `name`

	refs/tags/`name`::
	records any object name (not necessarily a commit
	object, or a tag object that points at a commit object).

	refs/remotes/`name`::
	records tip-of-the-tree commit objects of branches copied
	from a remote repository.

	packed-refs::
	records the same information as refs/heads/, refs/tags/,
	and friends record in a more efficient way. See
	linkgit:git-pack-refs[1].

	HEAD::
	A symref (see glossary) to the `refs/heads/` namespace
	describing the currently active branch. It does not mean
	much if the repository is not associated with any working tree
	(i.e. a 'bare' repository), but a valid git repository
	must have the HEAD file; some porcelains may use it to
	guess the designated "default" branch of the repository
	(usually 'master'). It is legal if the named branch
	'name' does not (yet) exist. In some legacy setups, it is
	a symbolic link instead of a symref that points at the current
	branch.
	+
	HEAD can also record a specific commit directly, instead of
	being a symref to point at the current branch. Such a state
	is often called 'detached HEAD', and almost all commands work
	identically as normal. See linkgit:git-checkout[1] for
	details.

	branches::
	A slightly deprecated way to store shorthands to be used
	to specify URL to `git fetch`, `git pull` and `git push`
	commands is to store a file in `branches/<name>` and
	give 'name' to these commands in place of 'repository'
	argument.

	hooks::
	Hooks are customization scripts used by various git
	commands. A handful of sample hooks are installed when
	`git init` is run, but all of them are disabled by
	default. To enable, they need to be made executable.
	Read linkgit:githooks[5][hooks] for more details about
	each hook.

	index::
	The current index file for the repository. It is
	usually not found in a bare repository.

	info::
	Additional information about the repository is recorded
	in this directory.

	info/refs::
	This file helps dumb transports discover what refs are
	available in this repository. If the repository is
	published for dumb transports, this file should be
	regenerated by `git update-server-info` every time a tag
	or branch is created or modified. This is normally done
	from the `hooks/update` hook, which is run by the
	`git-receive-pack` command when you `git push` into the
	repository.

	info/grafts::
	This file records fake commit ancestry information, to
	pretend the set of parents a commit has is different
	from how the commit was actually created. One record
	per line describes a commit and its fake parents by
	listing their 40-byte hexadecimal object names separated
	by a space and terminated by a newline.

	info/exclude::
	This file, by convention among Porcelains, stores the
	exclude pattern list. `.gitignore` is the per-directory
	ignore file. `git status`, `git add`, `git rm` and `git
	clean` look at it but the core git commands do not look
	at it. See also: linkgit:gitignore[5].

	remotes::
	Stores shorthands to be used to give URL and default
	refnames to interact with remote repository to `git
	fetch`, `git pull` and `git push` commands.

	logs::
	Records of changes made to refs are stored in this
	directory. See the documentation on git-update-ref
	for more information.

	logs/refs/heads/`name`::
	Records all changes made to the branch tip named `name`.

	logs/refs/tags/`name`::
	Records all changes made to the tag named `name`.

	shallow::
	This is similar to `info/grafts` but is internally used
	and maintained by shallow clone mechanism. See `--depth`
	option to linkgit:git-clone[1] and linkgit:git-fetch[1].

	SEE ALSO
	--------
	linkgit:git-init[1],
	linkgit:git-clone[1],
	linkgit:git-fetch[1],
	linkgit:git-pack-refs[1],
	linkgit:git-gc[1],
	linkgit:git-checkout[1],
	linkgit:gitglossary[7],
	link:user-manual.html[The Git User's Manual]

	GIT
	---
	Part of the linkgit:git[1] suite.