Function find_filter

src/jrd/blb.cpp:2333–2368

static BlobFilter* find_filter(thread_db* tdbb, SSHORT from, SSHORT to)
{
/**************************************
 *
 *      f i n d _ f i l t e r
 *
 **************************************
 *
 * Functional description
 *      Find blob filter.
 *
 **************************************/
	SET_TDBB(tdbb);
	Database* dbb = tdbb->getDatabase();
	CHECK_DBB(dbb);

	BlobFilter* cache = dbb->dbb_blob_filters;
	for (; cache; cache = cache->blf_next)
	{
		if (cache->blf_from == from && cache->blf_to == to)
			return cache;
	}

	cache = BLF_lookup_internal_filter(tdbb, from, to);
	if (!cache) {
		cache = MET_lookup_filter(tdbb, from, to);
	}

	if (cache)
	{
		cache->blf_next = dbb->dbb_blob_filters;
		dbb->dbb_blob_filters = cache;
	}

	return cache;
}


blob_page* blb::get_next_page(thread_db* tdbb, WIN* window)