connection.py 文件源码

def _recv_tcp_full(self):
        """
        Receives a message from the network,
        internally encoded using the TCP full protocol.

        May raise InvalidChecksumError if the received data doesn't
        match its valid checksum.

        :return: the read message payload.
        """
        packet_len_seq = self.read(8)  # 4 and 4
        packet_len, seq = struct.unpack('<ii', packet_len_seq)

        body = self.read(packet_len - 12)
        checksum = struct.unpack('<I', self.read(4))[0]

        valid_checksum = crc32(packet_len_seq + body)
        if checksum != valid_checksum:
            raise InvalidChecksumError(checksum, valid_checksum)

        return body