class WEBrick::HTTPServlet::FileHandler

def shift_path_info(req, res, path_info, base=nil)
  tmp = path_info.shift
  base = base || set_filesystem_encoding(tmp)
  req.path_info = path_info.join
  req.script_name << base
  res.filename = File.expand_path(res.filename + base)
  check_filename(req, res, File.basename(res.filename))
end