[PATCH] git-unbundle - unbundle objects and references for disconnected transfer.

[Mark Levedahl <mdl123@verizon.net>]

Some workflows require coordinated development between repositories on
machines that can never be connected. This utility unpacks a bundle
containing objects and associated references (heads or tags) into the
current repository, effectively supporting git-push like operations
between disconnected systems.

Signed-off-by: Mark Levedahl <mdl123@verizon.net>
---
 git-unbundle |   75 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 75 insertions(+), 0 deletions(-)
 create mode 100755 git-unbundle

diff --git a/git-unbundle b/git-unbundle
new file mode 100755
index 0000000..5ea4ae6
--- /dev/null
+++ b/git-unbundle
@@ -0,0 +1,75 @@
+#!/bin/sh
+# unpack a git-bundle file into current repository
+#
+# See git-bundle.
+
+die() {
+	echo >&2 "$@"
+	exit 1
+}
+
+bfile=bundle.zip
+force=
+shallow=
+while case "$#" in 0) break ;; esac
+do
+	case "$1" in
+	--bare)
+		export GIT_DIR=.;;
+	-f|--f|--fo|--for|--forc|--force)
+		force=1;;
+	-h|--h|--he|--hel|--help)
+		echo "usage: git-unbundle [--bare] [-f|--force] [--shallow] [bundle (default is bundle.zip)]"
+		exit;;
+	-s|--s|--sh|--sha|--shal|--shall|--shallo|--shallow)
+		shallow=1;;
+	-*)
+		die "unknown option: $1";;
+	*)
+		bfile="$1";;
+	esac
+	shift
+done
+
+[ -e "$bfile" ] || die "cannot find $bfile"
+GIT_DIR=$(git-rev-parse --git-dir) || die "Not in a git directory"
+
+# get the objects
+unzip -p "$bfile" .gitBundlePack | git-unpack-objects
+
+# check each reference, assure that the result would be valid before updating local ref
+unzip -p "$bfile" .gitBundleReferences | while read sha1 ref ; do
+	if [ -z "$shallow" ] ; then
+		result=$(git fsck $sha1)
+		havemissing=$(echo "$result" | grep '^missing')
+	else
+		# accept a shallow transfer
+		havemissing=
+	fi
+	ok=
+	if [ ! -z "$havemissing" ] ; then
+		echo "Not updating: $ref to $sha1"
+		echo "Bundle does not contain all required objects. (possibly partial) errors:"
+		echo "$result" | head
+	elif [ -z "$force" ] ; then
+		# update only if non-fastforward
+		local=$(git-rev-parse --verify "$ref^0" 2>/dev/null)
+		if [ ! -z "$local" ] ; then
+			mb=$(git-merge-base $local $sha1)
+			if [ "$mb" != "$local" ] ; then
+				echo "Not applying non-fast forward update: $ref"
+			else
+				ok=1
+			fi
+		else
+			ok=1
+		fi
+	else
+		#forced, accept non-fast forward update
+		ok=1
+	fi
+	if [ ! -z "$ok" ] ; then
+		echo "updating: $ref to $sha1"
+		git-update-ref -m "git-unbundle update" $ref $sha1
+	fi
+done
-- 
1.5.0.rc3.24.g0c5e