Function PAR_procedure_parms

src/jrd/par.cpp:1171–1265

Parse some procedure parameters.

// Parse some procedure parameters.
void PAR_procedure_parms(thread_db* tdbb, CompilerScratch* csb, jrd_prc* procedure,
	MessageNode** message_ptr, ValueListNode** sourceList, ValueListNode** targetList, bool input_flag)
{
	SET_TDBB(tdbb);
	SLONG count = csb->csb_blr_reader.getWord();
	const SLONG inputCount = procedure->getInputFields().getCount();

	// Check to see if the parameter count matches
	if (input_flag ?
			(count < (inputCount - procedure->getDefaultCount()) || (count > inputCount) ) :
			(count != SLONG(procedure->getOutputFields().getCount())))
	{
		PAR_error(csb, Arg::Gds(input_flag ? isc_prcmismat : isc_prc_out_param_mismatch) <<
						Arg::Str(procedure->getName().toString()));
	}

	if (count || input_flag && procedure->getDefaultCount())
	{
		MemoryPool& pool = *tdbb->getDefaultPool();

		// We have a few parameters. Get on with creating the message block
		// Outer messages map may start with 2, but they are always in the routine start.
		USHORT n = ++csb->csb_msg_number;
		if (n < 2)
			csb->csb_msg_number = n = 2;
		CompilerScratch::csb_repeat* tail = CMP_csb_element(csb, n);

		MessageNode* message = tail->csb_message = *message_ptr = FB_NEW_POOL(pool) MessageNode(pool);
		message->messageNumber = n;

		const Format* format = input_flag ? procedure->getInputFormat() : procedure->getOutputFormat();
		/* dimitr: procedure (with its parameter formats) is allocated out of
				   its own pool (prc_request->req_pool) and can be freed during
				   the cache cleanup (MET_clear_cache). Since the current
				   tdbb default pool is different from the procedure's one,
				   it's dangerous to copy a pointer from one request to another.
				   As an experiment, I've decided to copy format by value
				   instead of copying the reference. Since Format structure
				   doesn't contain any pointers, it should be safe to use a
				   default assignment operator which does a simple byte copy.
				   This change fixes one serious bug in the current codebase.
				   I think that this situation can (and probably should) be
				   handled by the metadata cache (via incrementing prc_use_count)
				   to avoid unexpected cache cleanups, but that area is out of my
				   knowledge. So this fix should be considered a temporary solution.

		message->format = format;
		*/
		Format* fmt_copy = Format::newFormat(pool, format->fmt_count);
		*fmt_copy = *format;
		message->format = fmt_copy;
		// --- end of fix ---

		n = format->fmt_count / 2;

		ValueListNode* sourceValues = *sourceList = FB_NEW_POOL(pool) ValueListNode(pool, n);
		ValueListNode* targetValues = *targetList = FB_NEW_POOL(pool) ValueListNode(pool, n);