Method walk_pointer_page

src/jrd/validation.cpp:2567–2724

}

Validation::RTN Validation::walk_pointer_page(jrd_rel* relation, ULONG sequence)
{
/**************************************
 *
 *	w a l k _ p o i n t e r _ p a g e
 *
 **************************************
 *
 * Functional description
 *	Walk a pointer page for a relation.  Return rtn_ok if there are more to go.
 *
 **************************************/
	Database* dbb = vdr_tdbb->getDatabase();

	const vcl* vector = relation->getBasePages()->rel_pages;

	if (!vector || sequence >= vector->count())
		return corrupt(VAL_P_PAGE_LOST, relation, sequence);

	pointer_page* page = 0;
	WIN window(DB_PAGE_SPACE, -1);
	window.win_flags = WIN_garbage_collector;

	fetch_page(true, (*vector)[sequence], pag_pointer, &window, &page);

#ifdef DEBUG_VAL_VERBOSE
	if (VAL_debug_level)
	{
		fprintf(stdout, "walk_pointer_page: page %d relation %d sequence %d\n",
				   (*vector)[sequence], relation->rel_id, sequence);
	}
#endif

	// Give the page a quick once over

	if (page->ppg_relation != relation->rel_id || page->ppg_sequence != sequence)
	{
		release_page(&window);
		return corrupt(VAL_P_PAGE_INCONSISTENT, relation, (*vector)[sequence], sequence);
	}

	// Walk the data pages (someday we may optionally walk pages with "large objects"

	ULONG seq = sequence * dbb->dbb_dp_per_pp;
	UCHAR* bits = (UCHAR*) (page->ppg_page + dbb->dbb_dp_per_pp);
	bool marked = false;
	USHORT slot = 0;
	for (ULONG* pages = page->ppg_page; slot < page->ppg_count; slot++, pages++, seq++)
	{
		if (*pages)
		{
			UCHAR new_pp_bits = 0;

			// If walk_data_page() below going to evaluate conditions expressions,
			// pointer page should be released to avoid deadlocks.

			const bool releasePP = vdr_cond_idx.hasData();
			if (releasePP)