#!/bin/rc

flag e +

repo=$1
branch=$2
tag=$3
out=$4

fn checkstatus {}

if(git -C $repo show-ref -q --verify refs/heads/$branch)
	parent=(-p $branch)
if not parent=()

message='oasis built by '`{id -un}
commit=`{echo $message | git -C $repo commit-tree $tag $parent} ; checkstatus
git -C $repo update-ref refs/heads/$branch $commit
echo $commit > $out.tmp && mv $out.tmp $out