class Rackup::Handler::WEBrick

def service(req, res)
  env = req.meta_vars
  env.delete_if { |k, v| v.nil? }
  input = Input.new(req)
  env.update(
    ::Rack::RACK_INPUT => input,
    ::Rack::RACK_ERRORS => $stderr,
    ::Rack::RACK_URL_SCHEME => ["yes", "on", "1"].include?(env[::Rack::HTTPS]) ? "https" : "http",
    ::Rack::RACK_IS_HIJACK => true,
  )
  env[::Rack::QUERY_STRING] ||= ""
  unless env[::Rack::PATH_INFO] == ""
    path, n = req.request_uri.path, env[::Rack::SCRIPT_NAME].length
    env[::Rack::PATH_INFO] = path[n, path.length - n]
  end
  env[::Rack::REQUEST_PATH] ||= [env[::Rack::SCRIPT_NAME], env[::Rack::PATH_INFO]].join
  status, headers, body = @app.call(env)
  begin
    res.status = status
    if value = headers[::Rack::RACK_HIJACK]
      io_lambda = value
      body = nil
    elsif !body.respond_to?(:to_path) && !body.respond_to?(:each)
      io_lambda = body
      body = nil
    end
    if value = headers.delete('set-cookie')
      res.cookies.concat(Array(value))
    end
    headers.each do |key, value|
      # Skip keys starting with rack., per Rack SPEC
      next if key.start_with?('rack.')
      # Since WEBrick won't accept repeated headers,
      # merge the values per RFC 1945 section 4.2.
      value = value.join(", ") if Array === value
      res[key] = value
    end
    if io_lambda
      protocol = headers['rack.protocol'] || headers['upgrade']
      if protocol
        # Set all the headers correctly for an upgrade response:
        res.upgrade!(protocol)
      end
      res.body = io_lambda
    elsif body.respond_to?(:to_path)
      res.body = ::File.open(body.to_path, 'rb')
    else
      buffer = String.new
      body.each do |part|
        buffer << part
      end
      res.body = buffer
    end
  ensure
    body.close if body.respond_to?(:close)
  end
end