Add git-submodule command

This command can be used to initialize, update and inspect submodules. It
uses a .gitmodules file, readable by git-config, in the top level directory
of the 'superproject' to specify a mapping between submodule paths and
repository url.

Example .gitmodules layout:

[module "git"]
	url = git://git.kernel.org/pub/scm/git/git.git

With this entry in .gitmodules (and a commit reference in the index entry for
the path "git"), the command 'git submodule init' will clone the repository
at kernel.org into the directory "git".

Known issues
============
There is currently no way to override the url found in the .gitmodules file,
except by manually creating the subproject repository. The place to fix this
in the script has a rather long comment about a possible plan.

Funny paths will be quoted in the output from git-ls-files, but git-submodule
does not attempt to unquote (or even detect the presence of) such paths.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/.gitignore b/.gitignore
index 4dc0c395fa7d6e7cff7588ee66c928c954cc014d..8fc492379242facc11bb863699f7aa7b2d52f75e 100644 (file)
--- a/.gitignore
+++ b/.gitignore
@@ -126,6 +126,7 @@ git-ssh-push
 git-ssh-upload
 git-status
 git-stripspace
+git-submodule
 git-svn
 git-svnimport
 git-symbolic-ref

diff --git a/Documentation/cmd-list.perl b/Documentation/cmd-list.perl
index 443802a9a3e4982c33f831217602ea600f0f2775..51dc6b4105e04e199f02d137f827c9ac14dfbdf7 100755 (executable)
--- a/Documentation/cmd-list.perl
+++ b/Documentation/cmd-list.perl
@@ -180,6 +180,7 @@ git-ssh-fetch                           synchingrepositories
 git-ssh-upload                          synchingrepositories
 git-status                              mainporcelain
 git-stripspace                          purehelpers
+git-submodule                           mainporcelain
 git-svn                                 foreignscminterface
 git-svnimport                           foreignscminterface
 git-symbolic-ref                        plumbingmanipulators

diff --git a/Documentation/git-submodule.txt b/Documentation/git-submodule.txt
new file mode 100644 (file)
index 0000000..cb0424f
--- /dev/null
+++ b/Documentation/git-submodule.txt
@@ -0,0 +1,65 @@
+git-submodule(1)
+================
+
+NAME
+----
+git-submodule - Initialize, update or inspect submodules
+
+
+SYNOPSIS
+--------
+'git-submodule' [--quiet] [--cached] [status|init|update] [--] [<path>...]
+
+
+COMMANDS
+--------
+status::
+       Show the status of the submodules. This will print the SHA-1 of the
+       currently checked out commit for each submodule, along with the
+       submodule path and the output of gitlink:git-describe[1] for the
+       SHA-1. Each SHA-1 will be prefixed with `-` if the submodule is not
+       initialized and `+` if the currently checked out submodule commit
+       does not match the SHA-1 found in the index of the containing
+       repository. This command is the default command for git-submodule.
+
+init::
+       Initialize the submodules, i.e. clone the git repositories specified
+       in the .gitmodules file and checkout the submodule commits specified
+       in the index of the containing repository. This will make the
+       submodules HEAD be detached.
+
+update::
+       Update the initialized submodules, i.e. checkout the submodule commits
+       specified in the index of the containing repository. This will make
+       the submodules HEAD be detached.
+
+
+OPTIONS
+-------
+-q, --quiet::
+       Only print error messages.
+
+--cached::
+       Display the SHA-1 stored in the index, not the SHA-1 of the currently
+       checked out submodule commit. This option is only valid for the
+       status command.
+
+<path>::
+       Path to submodule(s). When specified this will restrict the command
+       to only operate on the submodules found at the specified paths.
+
+FILES
+-----
+When cloning submodules, a .gitmodules file in the top-level directory
+of the containing repository is used to find the url of each submodule.
+This file should be formatted in the same way as $GIR_DIR/config. The key
+to each submodule url is "module.$path.url".
+
+
+AUTHOR
+------
+Written by Lars Hjemli <hjemli@gmail.com>
+
+GIT
+---
+Part of the gitlink:git[7] suite

diff --git a/Makefile b/Makefile
index 29243c6e8b49958ddcb08df0eb4223b14fd3e19f..5cf2169ef06ebae1c54aff61fba07cb3b0a684d3 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -209,7 +209,7 @@ SCRIPT_SH = \
        git-applymbox.sh git-applypatch.sh git-am.sh \
        git-merge.sh git-merge-stupid.sh git-merge-octopus.sh \
        git-merge-resolve.sh git-merge-ours.sh \
-       git-lost-found.sh git-quiltimport.sh
+       git-lost-found.sh git-quiltimport.sh git-submodule.sh
 
 SCRIPT_PERL = \
        git-add--interactive.perl \

diff --git a/git-submodule.sh b/git-submodule.sh
new file mode 100755 (executable)
index 0000000..6ed5a6c
--- /dev/null
+++ b/git-submodule.sh
@@ -0,0 +1,194 @@
+#!/bin/sh
+#
+# git-submodules.sh: init, update or list git submodules
+#
+# Copyright (c) 2007 Lars Hjemli
+
+USAGE='[--quiet] [--cached] [status|init|update] [--] [<path>...]'
+. git-sh-setup
+require_work_tree
+
+init=
+update=
+status=
+quiet=
+cached=
+
+#
+# print stuff on stdout unless -q was specified
+#
+say()
+{
+       if test -z "$quiet"
+       then
+               echo "$@"
+       fi
+}
+
+#
+# Run clone + checkout on missing submodules
+#
+# $@ = requested paths (default to all)
+#
+modules_init()
+{
+       git ls-files --stage -- "$@" | grep -e '^160000 ' |
+       while read mode sha1 stage path
+       do
+               # Skip submodule paths that already contain a .git directory.
+               # This will also trigger if $path is a symlink to a git
+               # repository
+               test -d "$path"/.git && continue
+
+               # If there already is a directory at the submodule path,
+               # expect it to be empty (since that is the default checkout
+               # action) and try to remove it.
+               # Note: if $path is a symlink to a directory the test will
+               # succeed but the rmdir will fail. We might want to fix this.
+               if test -d "$path"
+               then
+                       rmdir "$path" 2>/dev/null ||
+                       die "Directory '$path' exist, but is neither empty nor a git repository"
+               fi
+
+               test -e "$path" &&
+               die "A file already exist at path '$path'"
+
+               url=$(GIT_CONFIG=.gitmodules git-config module."$path".url)
+               test -z "$url" &&
+               die "No url found for submodule '$path' in .gitmodules"
+
+               # MAYBE FIXME: this would be the place to check GIT_CONFIG
+               # for a preferred url for this submodule, possibly like this:
+               #
+               # modname=$(GIT_CONFIG=.gitmodules git-config module."$path".name)
+               # alturl=$(git-config module."$modname".url)
+               #
+               # This would let the versioned .gitmodules file use the submodule
+               # path as key, while the unversioned GIT_CONFIG would use the
+               # logical modulename (if present) as key. But this would need
+               # another fallback mechanism if the module wasn't named.
+
+               git-clone -n "$url" "$path" ||
+               die "Clone of submodule '$path' failed"
+
+               (unset GIT_DIR && cd "$path" && git-checkout -q "$sha1") ||
+               die "Checkout of submodule '$path' failed"
+
+               say "Submodule '$path' initialized"
+       done
+}
+
+#
+# Checkout correct revision of each initialized submodule
+#
+# $@ = requested paths (default to all)
+#
+modules_update()
+{
+       git ls-files --stage -- "$@" | grep -e '^160000 ' |
+       while read mode sha1 stage path
+       do
+               if ! test -d "$path"/.git
+               then
+                       # Only mention uninitialized submodules when its
+                       # path have been specified
+                       test "$#" != "0" &&
+                       say "Submodule '$path' not initialized"
+                       continue;
+               fi
+               subsha1=$(unset GIT_DIR && cd "$path" &&
+                       git-rev-parse --verify HEAD) ||
+               die "Unable to find current revision of submodule '$path'"
+
+               if test "$subsha1" != "$sha1"
+               then
+                       (unset GIT_DIR && cd "$path" && git-fetch &&
+                               git-checkout -q "$sha1") ||
+                       die "Unable to checkout '$sha1' in submodule '$path'"
+
+                       say "Submodule '$path': checked out '$sha1'"
+               fi
+       done
+}
+
+#
+# List all registered submodules, prefixed with:
+#  - submodule not initialized
+#  + different revision checked out
+#
+# If --cached was specified the revision in the index will be printed
+# instead of the currently checked out revision.
+#
+# $@ = requested paths (default to all)
+#
+modules_list()
+{
+       git ls-files --stage -- "$@" | grep -e '^160000 ' |
+       while read mode sha1 stage path
+       do
+               if ! test -d "$path"/.git
+               then
+                       say "-$sha1 $path"
+                       continue;
+               fi
+               revname=$(unset GIT_DIR && cd "$path" && git-describe $sha1)
+               if git diff-files --quiet -- "$path"
+               then
+                       say " $sha1 $path ($revname)"
+               else
+                       if test -z "$cached"
+                       then
+                               sha1=$(unset GIT_DIR && cd "$path" && git-rev-parse --verify HEAD)
+                               revname=$(unset GIT_DIR && cd "$path" && git-describe $sha1)
+                       fi
+                       say "+$sha1 $path ($revname)"
+               fi
+       done
+}
+
+while case "$#" in 0) break ;; esac
+do
+       case "$1" in
+       init)
+               init=1
+               ;;
+       update)
+               update=1
+               ;;
+       status)
+               status=1
+               ;;
+       -q|--quiet)
+               quiet=1
+               ;;
+       --cached)
+               cached=1
+               ;;
+       --)
+               break
+               ;;
+       -*)
+               usage
+               ;;
+       *)
+               break
+               ;;
+       esac
+       shift
+done
+
+case "$init,$update,$status,$cached" in
+1,,,)
+       modules_init "$@"
+       ;;
+,1,,)
+       modules_update "$@"
+       ;;
+,,*,*)
+       modules_list "$@"
+       ;;
+*)
+       usage
+       ;;
+esac