class WebSocket::Driver::Hybi

def handshake_response
  begin
    extensions = @extensions.generate_response(@socket.env['HTTP_SEC_WEBSOCKET_EXTENSIONS'])
  rescue => error
    fail(:protocol_error, error.message)
    return nil
  end
  @headers['Sec-WebSocket-Extensions'] = extensions if extensions
  start   = 'HTTP/1.1 101 Switching Protocols'
  headers = [start, @headers.to_s, '']
  headers.join("\r\n")
end