Moved from backend/access to include/access

src/include/access/rtree.h

@@ -0,0 +1,98 @@
+/*-------------------------------------------------------------------------
+ *
+ * rtree.h--
+ *    common declarations for the rtree access method code.
+ *
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ * $Id: rtree.h,v 1.1 1996/08/27 21:50:21 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef RTREE_H
+#define RTREE_H
+
+/* see rtstrat.c for what all this is about */
+#define RTNStrategies			8
+#define RTLeftStrategyNumber		1
+#define RTOverLeftStrategyNumber	2
+#define RTOverlapStrategyNumber		3
+#define RTOverRightStrategyNumber	4
+#define RTRightStrategyNumber		5
+#define RTSameStrategyNumber		6
+#define RTContainsStrategyNumber	7
+#define RTContainedByStrategyNumber	8
+
+#define RTNProcs			3
+#define RT_UNION_PROC			1
+#define RT_INTER_PROC			2
+#define RT_SIZE_PROC			3
+
+#define F_LEAF		(1 << 0)
+
+typedef struct RTreePageOpaqueData {
+	uint32		flags;
+} RTreePageOpaqueData;
+
+typedef RTreePageOpaqueData	*RTreePageOpaque;
+
+/*
+ *  When we descend a tree, we keep a stack of parent pointers.
+ */
+
+typedef struct RTSTACK {
+	struct RTSTACK	*rts_parent;
+	OffsetNumber	rts_child;
+	BlockNumber	rts_blk;
+} RTSTACK;
+
+/*
+ *  When we're doing a scan, we need to keep track of the parent stack
+ *  for the marked and current items.  Also, rtrees have the following
+ *  property:  if you're looking for the box (1,1,2,2), on the internal
+ *  nodes you have to search for all boxes that *contain* (1,1,2,2), and
+ *  not the ones that match it.  We have a private scan key for internal
+ *  nodes in the opaque structure for rtrees for this reason.  See
+ *  access/index-rtree/rtscan.c and rtstrat.c for how it gets initialized.
+ */
+
+typedef struct RTreeScanOpaqueData {
+	struct RTSTACK	*s_stack;
+	struct RTSTACK	*s_markstk;
+	uint16		s_flags;
+	uint16		s_internalNKey;
+	ScanKey		s_internalKey;
+} RTreeScanOpaqueData;
+
+typedef RTreeScanOpaqueData	*RTreeScanOpaque;
+
+/*
+ *  When we're doing a scan and updating a tree at the same time, the
+ *  updates may affect the scan.  We use the flags entry of the scan's
+ *  opaque space to record our actual position in response to updates
+ *  that we can't handle simply by adjusting pointers.
+ */
+
+#define RTS_CURBEFORE	((uint16) (1 << 0))
+#define RTS_MRKBEFORE	((uint16) (1 << 1))
+
+/* root page of an rtree */
+#define P_ROOT		0
+
+/*
+ *  When we update a relation on which we're doing a scan, we need to
+ *  check the scan and fix it if the update affected any of the pages it
+ *  touches.  Otherwise, we can miss records that we should see.  The only
+ *  times we need to do this are for deletions and splits.  See the code in
+ *  rtscan.c for how the scan is fixed.  These two contants tell us what sort
+ *  of operation changed the index.
+ */
+
+#define	RTOP_DEL	0
+#define	RTOP_SPLIT	1
+
+/* defined in rtree.c */
+extern void freestack(RTSTACK *s);
+
+#endif /* RTREE_H */