Function PAR_desc

src/jrd/par.cpp:403–575

Parse a BLR descriptor. Return the alignment requirements of the datatype.

// Parse a BLR descriptor. Return the alignment requirements of the datatype.
USHORT PAR_desc(thread_db* tdbb, CompilerScratch* csb, dsc* desc, ItemInfo* itemInfo)
{
	if (itemInfo)
	{
		itemInfo->nullable = true;
		itemInfo->explicitCollation = false;
		itemInfo->fullDomain = false;
	}

	desc->clear();

	const USHORT dtype = csb->csb_blr_reader.getByte();

	switch (dtype)
	{
		case blr_not_nullable:
			PAR_desc(tdbb, csb, desc, itemInfo);
			if (itemInfo)
				itemInfo->nullable = false;
			break;

		case blr_domain_name:
		case blr_domain_name2:
		{
			const bool fullDomain = (csb->csb_blr_reader.getByte() == blr_domain_full);
			MetaName* name = FB_NEW_POOL(csb->csb_pool) MetaName(csb->csb_pool);
			csb->csb_blr_reader.getMetaName(*name);

			MetaNamePair namePair(*name, "");

			FieldInfo fieldInfo;
			bool exist = csb->csb_map_field_info.get(namePair, fieldInfo);
			MET_get_domain(tdbb, csb->csb_pool, *name, desc, (exist ? NULL : &fieldInfo));

			if (!exist)
				csb->csb_map_field_info.put(namePair, fieldInfo);

			if (itemInfo)
			{
				itemInfo->field = namePair;

				if (fullDomain)
				{
					itemInfo->nullable = fieldInfo.nullable;
					itemInfo->fullDomain = true;
				}
				else
					itemInfo->nullable = true;
			}

			if (dtype == blr_domain_name2)
			{
				const USHORT ttype = csb->csb_blr_reader.getWord();

				switch (desc->dsc_dtype)
				{
					case dtype_cstring:
					case dtype_text: