C++ (Cpp) mask_lp_flags Examples

Example #1

File: nbtxlog.c Project: gustavocolombelli/postgres

/*
 * Mask a btree page before performing consistency checks on it.
 */
void
btree_mask(char *pagedata, BlockNumber blkno)
{
	Page		page = (Page) pagedata;
	BTPageOpaque maskopaq;

	mask_page_lsn_and_checksum(page);

	mask_page_hint_bits(page);
	mask_unused_space(page);

	maskopaq = (BTPageOpaque) PageGetSpecialPointer(page);

	if (P_ISDELETED(maskopaq))
	{
		/*
		 * Mask page content on a DELETED page since it will be re-initialized
		 * during replay. See btree_xlog_unlink_page() for details.
		 */
		mask_page_content(page);
	}
	else if (P_ISLEAF(maskopaq))
	{
		/*
		 * In btree leaf pages, it is possible to modify the LP_FLAGS without
		 * emitting any WAL record. Hence, mask the line pointer flags. See
		 * _bt_killitems(), _bt_check_unique() for details.
		 */
		mask_lp_flags(page);
	}

	/*
	 * BTP_HAS_GARBAGE is just an un-logged hint bit. So, mask it. See
	 * _bt_killitems(), _bt_check_unique() for details.
	 */
	maskopaq->btpo_flags &= ~BTP_HAS_GARBAGE;

	/*
	 * During replay of a btree page split, we don't set the BTP_SPLIT_END
	 * flag of the right sibling and initialize the cycle_id to 0 for the same
	 * page. See btree_xlog_split() for details.
	 */
	maskopaq->btpo_flags &= ~BTP_SPLIT_END;
	maskopaq->btpo_cycleid = 0;
}

Example #2

File: gistxlog.c Project: AmiGanguli/postgres

/*
 * Mask a Gist page before running consistency checks on it.
 */
void
gist_mask(char *pagedata, BlockNumber blkno)
{
	Page		page = (Page) pagedata;

	mask_page_lsn_and_checksum(page);

	mask_page_hint_bits(page);
	mask_unused_space(page);

	/*
	 * NSN is nothing but a special purpose LSN. Hence, mask it for the same
	 * reason as mask_page_lsn_and_checksum.
	 */
	GistPageSetNSN(page, (uint64) MASK_MARKER);

	/*
	 * We update F_FOLLOW_RIGHT flag on the left child after writing WAL
	 * record. Hence, mask this flag. See gistplacetopage() for details.
	 */
	GistMarkFollowRight(page);

	if (GistPageIsLeaf(page))
	{
		/*
		 * In gist leaf pages, it is possible to modify the LP_FLAGS without
		 * emitting any WAL record. Hence, mask the line pointer flags. See
		 * gistkillitems() for details.
		 */
		mask_lp_flags(page);
	}

	/*
	 * During gist redo, we never mark a page as garbage. Hence, mask it to
	 * ignore any differences.
	 */
	GistClearPageHasGarbage(page);
}

Example #3

File: hash_xlog.c Project: dreamsxin/postgresql-1

/*
 * Mask a hash page before performing consistency checks on it.
 */
void
hash_mask(char *pagedata, BlockNumber blkno)
{
	Page		page = (Page) pagedata;
	HashPageOpaque opaque;

	mask_page_lsn(page);

	mask_page_hint_bits(page);
	mask_unused_space(page);

	opaque = (HashPageOpaque) PageGetSpecialPointer(page);

	if (opaque->hasho_flag & LH_UNUSED_PAGE)
	{
		/*
		 * Mask everything on a UNUSED page.
		 */
		mask_page_content(page);
	}
	else if ((opaque->hasho_flag & LH_BUCKET_PAGE) ||
			 (opaque->hasho_flag & LH_OVERFLOW_PAGE))
	{
		/*
		 * In hash bucket and overflow pages, it is possible to modify the
		 * LP_FLAGS without emitting any WAL record. Hence, mask the line
		 * pointer flags. See hashgettuple(), _hash_kill_items() for details.
		 */
		mask_lp_flags(page);
	}

	/*
	 * It is possible that the hint bit LH_PAGE_HAS_DEAD_TUPLES may remain
	 * unlogged. So, mask it. See _hash_kill_items() for details.
	 */
	opaque->hasho_flag &= ~LH_PAGE_HAS_DEAD_TUPLES;
}