c++boostbeast

How to see raw tcp data on async_accept failure?


I am using boost::beast library for both WebSocket and TCP server.

Because of requirement, I have to use same port. Thus I implemented server following it.

        void on_run() {
            // Set suggested timeout settings for the websocket
            m_ws.set_option(...);
            m_ws.async_accept(
                beast::bind_front_handler(
                    &WsSessionNoSSL::on_accept,
                    shared_from_this()));
        }

        virtual void on_accept(beast::error_code ec) {
            if(ec) {
                std::string msg = ec.message();
                CONSOLE_INFO("err: {}", msg);
                if(msg != "bad method") {
                    return fail(ec, "accept"); 
                } else {
                    doReadTcp();
                    return;
                }
            }          
            doReadWs();
        }
        void doReadTcp() {   
 m_ws.next_layer().async_read_some(boost::asio::buffer(m_recvData, 15),
                            [this, self = shared_from_this()](const boost::system::error_code &error,
                                                              size_t bytes_transferred) {
                                if(error) {
                                    return fail(error, "tcp read fail");
                                }
                                CONSOLE_INFO("recvs: {}", bytes_transferred);
                                doReadTcp();
                            });
        }
        void doReadWs() {
            m_ws.async_read(...);
        }

After accept function is failed, I try to read raw tcp data, however I wasn't able to know passed data. I can only know failure reason via ec.message(). When accept function is failed, can I know passed data?

If It is impossible what I thought, how to solve this problem?


Solution

  • I found solution.

                m_ws.async_accept(net::buffer(m_untilStr),
                    beast::bind_front_handler(
                        &WsSessionNoSSL::on_accept,
                        shared_from_this()));
    

    websocket::stream supports buffered accept function.

    Thus firstly tcp socket fill handshake data, call the async_accept(buffer, handler).