$GIT_COMMON_DIR: a new environment variable

This variable is intended to support multiple working directories
attached to a repository. Such a repository may have a main working
directory, created by either "git init" or "git clone" and one or more
linked working directories. These working directories and the main
repository share the same repository directory.

In linked working directories, $GIT_COMMON_DIR must be defined to point
to the real repository directory and $GIT_DIR points to an unused
subdirectory inside $GIT_COMMON_DIR. File locations inside the
repository are reorganized from the linked worktree view point:

 - worktree-specific such as HEAD, logs/HEAD, index, other top-level
   refs and unrecognized files are from $GIT_DIR.

 - the rest like objects, refs, info, hooks, packed-refs, shallow...
   are from $GIT_COMMON_DIR (except info/sparse-checkout, but that's
   a separate patch)

Scripts are supposed to retrieve paths in $GIT_DIR with "git rev-parse
--git-path", which will take care of "$GIT_DIR vs $GIT_COMMON_DIR"
business.

The redirection is done by git_path(), git_pathdup() and
strbuf_git_path(). The selected list of paths goes to $GIT_COMMON_DIR,
not the other way around in case a developer adds a new
worktree-specific file and it's accidentally promoted to be shared
across repositories (this includes unknown files added by third party
commands)

The list of known files that belong to $GIT_DIR are:

ADD_EDIT.patch BISECT_ANCESTORS_OK BISECT_EXPECTED_REV BISECT_LOG
BISECT_NAMES CHERRY_PICK_HEAD COMMIT_MSG FETCH_HEAD HEAD MERGE_HEAD
MERGE_MODE MERGE_RR NOTES_EDITMSG NOTES_MERGE_WORKTREE ORIG_HEAD
REVERT_HEAD SQUASH_MSG TAG_EDITMSG fast_import_crash_* logs/HEAD
next-index-* rebase-apply rebase-merge rsync-refs-* sequencer/*
shallow_*

Path mapping is NOT done for git_path_submodule(). Multi-checkouts are
not supported as submodules.

Helped-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Nguyễn Thái Ngọc Duy
2014-11-30 15:24:36 +07:00
committed by Junio C Hamano
parent af07b20d51
commit c7b3a3d2fe
6 changed files with 117 additions and 19 deletions

View File

@ -262,5 +262,21 @@ test_expect_success 'setup fake objects directory foo' 'mkdir foo'
test_git_path GIT_OBJECT_DIRECTORY=foo objects foo
test_git_path GIT_OBJECT_DIRECTORY=foo objects/foo foo/foo
test_git_path GIT_OBJECT_DIRECTORY=foo objects2 .git/objects2
test_expect_success 'setup common repository' 'git --git-dir=bar init'
test_git_path GIT_COMMON_DIR=bar index .git/index
test_git_path GIT_COMMON_DIR=bar HEAD .git/HEAD
test_git_path GIT_COMMON_DIR=bar logs/HEAD .git/logs/HEAD
test_git_path GIT_COMMON_DIR=bar objects bar/objects
test_git_path GIT_COMMON_DIR=bar objects/bar bar/objects/bar
test_git_path GIT_COMMON_DIR=bar info/exclude bar/info/exclude
test_git_path GIT_COMMON_DIR=bar info/grafts bar/info/grafts
test_git_path GIT_COMMON_DIR=bar remotes/bar bar/remotes/bar
test_git_path GIT_COMMON_DIR=bar branches/bar bar/branches/bar
test_git_path GIT_COMMON_DIR=bar logs/refs/heads/master bar/logs/refs/heads/master
test_git_path GIT_COMMON_DIR=bar refs/heads/master bar/refs/heads/master
test_git_path GIT_COMMON_DIR=bar hooks/me bar/hooks/me
test_git_path GIT_COMMON_DIR=bar config bar/config
test_git_path GIT_COMMON_DIR=bar packed-refs bar/packed-refs
test_git_path GIT_COMMON_DIR=bar shallow bar/shallow
test_done