+dryrun=
+while case "$#" in 0) break ;; esac
+do
+ case "$1" in
+ -n) dryrun=echo ;;
+ --) break ;;
+ -*) echo >&2 "usage: git-prune-script [ -n ] [ heads... ]"; exit 1 ;;
+ *) break ;;
+ esac
+ shift;
+done
+
+: ${GIT_DIR=.git}
+: ${GIT_OBJECT_DIRECTORY="${SHA1_FILE_DIRECTORY-"$GIT_DIR/objects"}"}
+
+# Defaulting to include .git/refs/*/* may be debatable from the
+# purist POV but power users can always give explicit parameters
+# to the script anyway.
+
+case "$#" in
+0)
+ x_40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
+ x_40="$x_40$x_40$x_40$x_40$x_40$x_40$x_40$x_40"
+ set x $(sed -ne "/^$x_40\$/p" \
+ "$GIT_DIR"/HEAD "$GIT_DIR"/refs/*/* /dev/null 2>/dev/null)
+ shift ;;
+esac
+
+git-fsck-cache --cache --unreachable "$@" |
+sed -ne '/unreachable /{
+ s/unreachable [^ ][^ ]* //
+ s|\(..\)|\1/|p
+}' | {
+ cd "$GIT_OBJECT_DIRECTORY" || exit
+ xargs -r $dryrun rm -f
+}
+