Function internal_enqueue

src/jrd/lck.cpp:1355–1456

static bool internal_enqueue(thread_db* tdbb, CheckStatusWrapper* statusVector, Lock* lock,
	USHORT level, SSHORT wait, bool convert_flg)
{
/**************************************
 *
 *	i n t e r n a l _ e n q u e u e
 *
 **************************************
 *
 * Functional description
 *	See if there is a compatible lock already held
 *	by this process; if not, go ahead and submit the
 *	lock to the real lock manager.
 *	NOTE: This routine handles both enqueueing
 *	and converting existing locks, since the convert
 *	will find itself in the hash table and convert
 *	itself upward.
 *
 **************************************/
	SET_TDBB(tdbb);
	Database* const dbb = tdbb->getDatabase();

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

	// look for an identical lock

	Lock* match = hash_get_lock(lock, 0, 0);
	if (match)
	{
		// if there are incompatible locks for which there are no blocking asts defined, give up

		if (!internal_compatible(match, lock, level))
		{
			// for now return a lock conflict; it would be better if we were to
			// do a wait on the other lock by setting some flag bit or some such

			(Arg::StatusVector(statusVector) << Arg::Gds(isc_lock_conflict)).copyTo(statusVector);
			return false;
		}

		// if there is still an identical lock, convert the lock, otherwise fall
		// through and enqueue a new one

		if ( (match = hash_get_lock(lock, 0, 0)) )
		{
			// if a conversion is necessary, update all identical
			// locks to reflect the new physical lock level

			if (level > match->lck_physical)
			{
				if (!dbb->lockManager()->convert(tdbb, statusVector, match->lck_id, level, wait,
						external_ast, lock))
				{
					return false;
				}

				for (Lock* update = match; update; update = update->lck_identical)