Function CVT2_blob_compare

src/jrd/cvt2.cpp:731–914

int CVT2_blob_compare(const dsc* arg1, const dsc* arg2, DecimalStatus decSt)
{
/**************************************
 *
 *	C V T 2 _ b l o b _ c o m p a r e
 *
 **************************************
 *
 * Functional description
 *	Compare two blobs.  Return (-1, 0, 1) if a<b, a=b, or a>b.
 *  Alternatively, it will try to compare a blob against a string;
 *	in this case, the string should be the second argument.
 * CVC: Ann Harrison asked for this function to make comparisons more
 * complete in the engine.
 *
 **************************************/

	SLONG l1, l2;
	USHORT ttype2;
	int ret_val = 0;

	thread_db* tdbb = NULL;
	SET_TDBB(tdbb);

	// DEV_BLKCHK (node, type_nod);

	if (arg1->dsc_dtype != dtype_blob)
		ERR_post(Arg::Gds(isc_wish_list) << Arg::Gds(isc_datnotsup));

	USHORT ttype1;
	if (arg1->dsc_sub_type == isc_blob_text)
		ttype1 = arg1->dsc_blob_ttype();       // Load blob character set and collation
	else
		ttype1 = ttype_binary;

	TextType* obj1 = INTL_texttype_lookup(tdbb, ttype1);
	ttype1 = obj1->getType();

	// Is arg2 a blob?
	if (arg2->dsc_dtype == dtype_blob)
	{
	    // Same blob id address?
		if (arg1->dsc_address == arg2->dsc_address)
			return 0;

		// Second test for blob id, checking relation and slot.
		const bid* bid1 = (bid*) arg1->dsc_address;
		const bid* bid2 = (bid*) arg2->dsc_address;
		if (*bid1 == *bid2)
		{
			return 0;
		}

		if (arg2->dsc_sub_type == isc_blob_text)
			ttype2 = arg2->dsc_blob_ttype();       // Load blob character set and collation
		else
			ttype2 = ttype_binary;