Documentation / repository-layout.txton commit Merge branch 'master-for-junio' of git://repo.or.cz/git/fastimport; branch 'maint' (99e6ac5)
   1git repository layout
   2=====================
   3
   4You may find these things in your git repository (`.git`
   5directory for a repository associated with your working tree, or
   6`'project'.git` directory for a public 'bare' repository).
   7
   8objects::
   9        Object store associated with this repository.  Usually
  10        an object store is self sufficient (i.e. all the objects
  11        that are referred to by an object found in it are also
  12        found in it), but there are couple of ways to violate
  13        it.
  14+
  15. You could populate the repository by running a commit walker
  16without `-a` option.  Depending on which options are given, you
  17could have only commit objects without associated blobs and
  18trees this way, for example.  A repository with this kind of
  19incomplete object store is not suitable to be published to the
  20outside world but sometimes useful for private repository.
  21. You also could have an incomplete but locally usable repository
  22by cloning shallowly.  See gitlink:git-clone[1].
  23. You can be using `objects/info/alternates` mechanism, or
  24`$GIT_ALTERNATE_OBJECT_DIRECTORIES` mechanism to 'borrow'
  25objects from other object stores.  A repository with this kind
  26of incomplete object store is not suitable to be published for
  27use with dumb transports but otherwise is OK as long as
  28`objects/info/alternates` points at the right object stores
  29it borrows from.
  30
  31objects/[0-9a-f][0-9a-f]::
  32        Traditionally, each object is stored in its own file.
  33        They are split into 256 subdirectories using the first
  34        two letters from its object name to keep the number of
  35        directory entries `objects` directory itself needs to
  36        hold.  Objects found here are often called 'unpacked'
  37        (or 'loose') objects.
  38
  39objects/pack::
  40        Packs (files that store many object in compressed form,
  41        along with index files to allow them to be randomly
  42        accessed) are found in this directory.
  43
  44objects/info::
  45        Additional information about the object store is
  46        recorded in this directory.
  47
  48objects/info/packs::
  49        This file is to help dumb transports discover what packs
  50        are available in this object store.  Whenever a pack is
  51        added or removed, `git update-server-info` should be run
  52        to keep this file up-to-date if the repository is
  53        published for dumb transports.  `git repack` does this
  54        by default.
  55
  56objects/info/alternates::
  57        This file records paths to alternate object stores that
  58        this object store borrows objects from, one pathname per
  59        line. Note that not only native Git tools use it locally,
  60        but the HTTP fetcher also tries to use it remotely; this
  61        will usually work if you have relative paths (relative
  62        to the object database, not to the repository!) in your
  63        alternates file, but it will not work if you use absolute
  64        paths unless the absolute path in filesystem and web URL
  65        is the same. See also 'objects/info/http-alternates'.
  66
  67objects/info/http-alternates::
  68        This file records URLs to alternate object stores that
  69        this object store borrows objects from, to be used when
  70        the repository is fetched over HTTP.
  71
  72refs::
  73        References are stored in subdirectories of this
  74        directory.  The `git prune` command knows to keep
  75        objects reachable from refs found in this directory and
  76        its subdirectories.
  77
  78refs/heads/`name`::
  79        records tip-of-the-tree commit objects of branch `name`
  80
  81refs/tags/`name`::
  82        records any object name (not necessarily a commit
  83        object, or a tag object that points at a commit object).
  84
  85refs/remotes/`name`::
  86        records tip-of-the-tree commit objects of branches copied
  87        from a remote repository.
  88
  89packed-refs::
  90        records the same information as refs/heads/, refs/tags/,
  91        and friends record in a more efficient way.  See
  92        gitlink:git-pack-refs[1].
  93
  94HEAD::
  95        A symref (see glossary) to the `refs/heads/` namespace
  96        describing the currently active branch.  It does not mean
  97        much if the repository is not associated with any working tree
  98        (i.e. a 'bare' repository), but a valid git repository
  99        *must* have the HEAD file; some porcelains may use it to
 100        guess the designated "default" branch of the repository
 101        (usually 'master').  It is legal if the named branch
 102        'name' does not (yet) exist.  In some legacy setups, it is
 103        a symbolic link instead of a symref that points at the current
 104        branch.
 105+
 106HEAD can also record a specific commit directly, instead of
 107being a symref to point at the current branch.  Such a state
 108is often called 'detached HEAD', and almost all commands work
 109identically as normal.  See gitlink:git-checkout[1] for
 110details.
 111
 112branches::
 113        A slightly deprecated way to store shorthands to be used
 114        to specify URL to `git fetch`, `git pull` and `git push`
 115        commands is to store a file in `branches/'name'` and
 116        give 'name' to these commands in place of 'repository'
 117        argument.
 118
 119hooks::
 120        Hooks are customization scripts used by various git
 121        commands.  A handful of sample hooks are installed when
 122        `git init` is run, but all of them are disabled by
 123        default.  To enable, they need to be made executable.
 124        Read link:hooks.html[hooks] for more details about
 125        each hook.
 126
 127index::
 128        The current index file for the repository.  It is
 129        usually not found in a bare repository.
 130
 131info::
 132        Additional information about the repository is recorded
 133        in this directory.
 134
 135info/refs::
 136        This file helps dumb transports discover what refs are
 137        available in this repository.  If the repository is
 138        published for dumb transports, this file should be
 139        regenerated by `git update-server-info` every time a tag
 140        or branch is created or modified.  This is normally done
 141        from the `hooks/update` hook, which is run by the
 142        `git-receive-pack` command when you `git push` into the
 143        repository.
 144
 145info/grafts::
 146        This file records fake commit ancestry information, to
 147        pretend the set of parents a commit has is different
 148        from how the commit was actually created.  One record
 149        per line describes a commit and its fake parents by
 150        listing their 40-byte hexadecimal object names separated
 151        by a space and terminated by a newline.
 152
 153info/exclude::
 154        This file, by convention among Porcelains, stores the
 155        exclude pattern list. `.gitignore` is the per-directory
 156        ignore file.  `git status`, `git add`, `git rm` and `git
 157        clean` look at it but the core git commands do not look
 158        at it.  See also: gitlink:git-ls-files[1] `--exclude-from`
 159        and `--exclude-per-directory`.
 160
 161remotes::
 162        Stores shorthands to be used to give URL and default
 163        refnames to interact with remote repository to `git
 164        fetch`, `git pull` and `git push` commands.
 165
 166logs::
 167        Records of changes made to refs are stored in this
 168        directory.  See the documentation on git-update-ref
 169        for more information.
 170
 171logs/refs/heads/`name`::
 172        Records all changes made to the branch tip named `name`.
 173
 174logs/refs/tags/`name`::
 175        Records all changes made to the tag named `name`.
 176
 177shallow::
 178        This is similar to `info/grafts` but is internally used
 179        and maintained by shallow clone mechanism.  See `--depth`
 180        option to gitlink:git-clone[1] and gitlink:git-fetch[1].
 181