File Directive PDU data length field is off by 1

[avan989]

From the code, it looks like the "PDU data length" for the File Directive does not include the directive code. From CCSDS 727.0-B-5 Section 5.2.1.1

The data field of File Directives shall consist of a Directive Code octet followed by a Directive Parameter field

Example from cfdp_pdu_eof.rb:

openc3-cosmos-cfdp/microservices/CFDP/lib/cfdp_pdu/cfdp_pdu_eof.rb

Lines 41 to 47 in fa4b65f

	pdu = build_initial_pdu(type: "FILE_DIRECTIVE", destination_entity: destination_entity, transmission_mode: transmission_mode, file_size: file_size, segmentation_control: segmentation_control)
	pdu_header_part_1_length = pdu.length # Measured here before writing variable data
	pdu_header = pdu.build_variable_header(source_entity_id: source_entity['id'], transaction_seq_num: transaction_seq_num, destination_entity_id: destination_entity['id'], directive_code: "EOF")
	pdu_header_part_2_length = pdu_header.length
	pdu_contents = pdu.build_eof_pdu_contents(condition_code: condition_code, file_checksum: file_checksum, file_size: file_size, canceling_entity_id: canceling_entity_id)
	pdu.write("VARIABLE_DATA", pdu_header + pdu_contents)
	pdu.write("PDU_DATA_LENGTH", pdu.length - pdu_header_part_1_length - pdu_header_part_2_length)

[ryanmelt]

You are correct. Fill fix.