Function get_auth_flags

src/brpc/socket.cpp:340–342

        return _pc_and_udmsg.extra() & 0x3FFF;
    }
    uint32_t get_auth_flags() const {
       return (_pc_and_udmsg.extra() >> 14) & 0x03;
    }
    void clear_pipelined_count_and_auth_flags() {
        _pc_and_udmsg.reset_extra();
    }