def rootname_from_archive_olpath(node):
    """
    Find rootname from ARCHIVE_OLPATH property.
    Return None if not found.
    """
    olpath = node.get_property('ARCHIVE_OLPATH')
    if olpath:
        olpathlist = olpath.split('/', 1)
        if len(olpathlist) > 1:
            rootname, dummy = olpathlist
        else:
            rootname = olpath
        return rootname
    return None
