Function internal_downgrade

src/jrd/lck.cpp:1309–1352

static USHORT internal_downgrade(thread_db* tdbb, CheckStatusWrapper* statusVector, Lock* first)
{
/**************************************
 *
 *	i n t e r n a l _ d o w n g r a d e
 *
 **************************************
 *
 * Functional description
 *	Set the physical lock value of all locks identical
 *	to the passed lock.  It should be the same as the
 *	highest logical level.
 *
 **************************************/
	SET_TDBB(tdbb);
	Database* const dbb = tdbb->getDatabase();

	fb_assert(LCK_CHECK_LOCK(first));
	fb_assert(first->lck_compatible);

	// find the highest required lock level

	USHORT level = LCK_none;
	for (const Lock* lock = first; lock; lock = lock->lck_identical)
		level = MAX(level, lock->lck_logical);

	// if we can convert to that level, set all identical locks as having that level

	if (level < first->lck_physical)
	{
		if (dbb->lockManager()->convert(tdbb, statusVector, first->lck_id, level, LCK_NO_WAIT,
				external_ast, first))
		{
			for (Lock* lock = first; lock; lock = lock->lck_identical)
			{
				lock->lck_physical = level;
			}

			return level;
		}
	}

	return first->lck_physical;
}


static bool internal_enqueue(thread_db* tdbb, CheckStatusWrapper* statusVector, Lock* lock,