Merge branch 'ml/submodule-foreach'

* ml/submodule-foreach:
  git-submodule - Add 'foreach' subcommand

Documentation/git-submodule.txt

@@ -14,6 +14,7 @@ SYNOPSIS
 'git submodule' [--quiet] init [--] [<path>...]
 'git submodule' [--quiet] update [--init] [--] [<path>...]
 'git submodule' [--quiet] summary [--summary-limit <n>] [commit] [--] [<path>...]
+'git submodule' [--quiet] foreach <command>
 
 
 DESCRIPTION
@@ -123,6 +124,22 @@ summary::
 	in the submodule between the given super project commit and the
 	index or working tree (switched by --cached) are shown.
 
+foreach::
+	Evaluates an arbitrary shell command in each checked out submodule.
+	The command has access to the variables $path and $sha1:
+	$path is the name of the submodule directory relative to the
+	superproject, and $sha1 is the commit as recorded in the superproject.
+	Any submodules defined in the superproject but not checked out are
+	ignored by this command. Unless given --quiet, foreach prints the name
+	of each submodule before evaluating the command.
+	A non-zero return from the command in any submodule causes
+	the processing to terminate. This can be overridden by adding '|| :'
+	to the end of the command.
++
+As an example, "git submodule foreach 'echo $path `git rev-parse HEAD`' will
+show the path and currently checked out commit for each submodule.
+
+
 OPTIONS
 -------
 -q::

git-submodule.sh

@@ -6,7 +6,7 @@
 
 USAGE="[--quiet] [--cached] \
 [add <repo> [-b branch] <path>]|[status|init|update [-i|--init]|summary [-n|--summary-limit <n>] [<commit>]] \
-[--] [<path>...]"
+[--] [<path>...]|[foreach <command>]"
 OPTIONS_SPEC=
 . git-sh-setup
 require_work_tree
@@ -198,6 +198,26 @@ cmd_add()
 	die "Failed to register submodule '$path'"
 }
 
+#
+# Execute an arbitrary command sequence in each checked out
+# submodule
+#
+# $@ = command to execute
+#
+cmd_foreach()
+{
+	git ls-files --stage | grep '^160000 ' |
+	while read mode sha1 stage path
+	do
+		if test -e "$path"/.git
+		then
+			say "Entering '$path'"
+			(cd "$path" && eval "$@") ||
+			die "Stopping at '$path'; script returned non-zero status."
+		fi
+	done
+}
+
 #
 # Register submodules in .git/config
 #
@@ -583,7 +603,7 @@ cmd_status()
 while test $# != 0 && test -z "$command"
 do
 	case "$1" in
-	add | init | update | status | summary)
+	add | foreach | init | update | status | summary)
 		command=$1
 		;;
 	-q|--quiet)