Assuming one message that gets split into multiple TCP packets of length 10 bytes. Foo format contains the type of message but there is no length field. Foo contains a text field which could be variable. The end of the message is marked. { return MAX_MESSAGE_LEN }
dissect_foo(...) { tcp_dissect_pdus(...get_foo_pdu_length...) }
Please provide an example where the user needs to determine the length of the PDU and there is no length field. All your examples have a length field in the protocol.