Function VIO_get_current

src/jrd/vio.cpp:2988–3216

bool VIO_get_current(thread_db* tdbb,
					record_param* rpb,
					jrd_tra* transaction,
					MemoryPool* pool,
					bool foreign_key,
					bool& rec_tx_active)
{
/**************************************
 *
 *	V I O _ g e t _ c u r r e n t
 *
 **************************************
 *
 * Functional description
 *	Get the current (most recent) version of a record.  This is
 *	called by IDX to determine whether a unique index has been
 *	duplicated.  If the target record's transaction is active,
 *	wait for it.  If the record is deleted or disappeared, return
 *	false.  If the record is committed, return true.
 *	If foreign_key is true, we are checking for a foreign key,
 *	looking to see if a primary key/unique key exists.  For a
 *	no wait transaction, if state of transaction inserting primary key
 *	record is tra_active, we should not see the uncommitted record
 *
 **************************************/
	SET_TDBB(tdbb);

#ifdef VIO_DEBUG
	jrd_rel* relation = rpb->rpb_relation;
	VIO_trace(DEBUG_TRACE,
		"VIO_get_current (rel_id %u, record_param %" QUADFORMAT"d, transaction %" SQUADFORMAT", pool %p)\n",
		relation->rel_id, rpb->rpb_number.getValue(), transaction ? transaction->tra_number : 0,
		(void*) pool);
#endif

	rec_tx_active = false;

	bool counted = false;

	while (true)
	{
		// If the record doesn't exist, no problem.

		if (!DPM_get(tdbb, rpb, LCK_read))
			return false;

#ifdef VIO_DEBUG
		VIO_trace(DEBUG_TRACE_INFO,
			"   record  %" SLONGFORMAT":%d, rpb_trans %" SQUADFORMAT
			", flags %d, back %" SLONGFORMAT":%d, fragment %" SLONGFORMAT":%d\n",
			rpb->rpb_page, rpb->rpb_line, rpb->rpb_transaction_nr,
			rpb->rpb_flags, rpb->rpb_b_page, rpb->rpb_b_line,
			rpb->rpb_f_page, rpb->rpb_f_line);
#endif

		// Get data if there is data.

		if (rpb->rpb_flags & rpb_damaged)