Buffer Overrun response may not be sent on expedited download requests

[msftrncs]

CANopen_SDOSVR_ST/SDO SVR Protocol Processor.ST

Lines 374 to 384 in 30893d8

	i := 0;
	WHILE i < Request_LEN DO
	IF i >= Response_BUFFER_LEN THEN
	EXIT;
	END_IF
	Response_BUFFER_PTR^[i] := CANSDO_DATA[i + 4]; (* copy data *)
	i := i + 1;
	END_WHILE
	Request_LEN := i; (* length of data downloaded *)
	(* if request length was known, then its a problem if there was more data than buffer, but not if length was not known *)
	Request_BUFFEROVERRUN := SEL( Request_LEN_KNOWN, FALSE, i > Response_BUFFER_LEN );

The expression for Request_BUFFEROVERRUN may never be set because i will not exceed Response_BUFFER_LEN when the WHILE loop exits upon detecting that the supplied buffer has been filled to capacity.

The correction requires rearranging lines (382-384):

		(* if request length was known, then its a problem if there was more data than buffer, but not if length was not known *)
		Request_BUFFEROVERRUN := SEL( Request_LEN_KNOWN, FALSE, Request_LEN > Response_BUFFER_LEN );
		IF Request_BUFFEROVERRUN THEN
			Request_LEN := i; (* length of data downloaded *)
		END_IF