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-rw-r--r--src/backend/access/rtree/rtget.c283
1 files changed, 0 insertions, 283 deletions
diff --git a/src/backend/access/rtree/rtget.c b/src/backend/access/rtree/rtget.c
deleted file mode 100644
index 87ebb60559c..00000000000
--- a/src/backend/access/rtree/rtget.c
+++ /dev/null
@@ -1,283 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * rtget.c
- * fetch tuples from an rtree scan.
- *
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *
- * IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/rtree/Attic/rtget.c,v 1.27 2002/06/20 20:29:25 momjian Exp $
- *
- *-------------------------------------------------------------------------
- */
-
-#include "postgres.h"
-
-#include "access/iqual.h"
-#include "access/relscan.h"
-#include "access/rtree.h"
-
-static OffsetNumber findnext(IndexScanDesc s, Page p, OffsetNumber n,
- ScanDirection dir);
-static bool rtscancache(IndexScanDesc s, ScanDirection dir);
-static bool rtfirst(IndexScanDesc s, ScanDirection dir);
-static bool rtnext(IndexScanDesc s, ScanDirection dir);
-
-
-Datum
-rtgettuple(PG_FUNCTION_ARGS)
-{
- IndexScanDesc s = (IndexScanDesc) PG_GETARG_POINTER(0);
- ScanDirection dir = (ScanDirection) PG_GETARG_INT32(1);
- bool res;
-
- /* if we have it cached in the scan desc, just return the value */
- if (rtscancache(s, dir))
- PG_RETURN_BOOL(true);
-
- /* not cached, so we'll have to do some work */
- if (ItemPointerIsValid(&(s->currentItemData)))
- res = rtnext(s, dir);
- else
- res = rtfirst(s, dir);
- PG_RETURN_BOOL(res);
-}
-
-static bool
-rtfirst(IndexScanDesc s, ScanDirection dir)
-{
- Buffer b;
- Page p;
- OffsetNumber n;
- OffsetNumber maxoff;
- RTreePageOpaque po;
- RTreeScanOpaque so;
- RTSTACK *stk;
- BlockNumber blk;
- IndexTuple it;
-
- b = ReadBuffer(s->indexRelation, P_ROOT);
- p = BufferGetPage(b);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
- so = (RTreeScanOpaque) s->opaque;
-
- for (;;)
- {
- maxoff = PageGetMaxOffsetNumber(p);
- if (ScanDirectionIsBackward(dir))
- n = findnext(s, p, maxoff, dir);
- else
- n = findnext(s, p, FirstOffsetNumber, dir);
-
- while (n < FirstOffsetNumber || n > maxoff)
- {
- ReleaseBuffer(b);
- if (so->s_stack == (RTSTACK *) NULL)
- return false;
-
- stk = so->s_stack;
- b = ReadBuffer(s->indexRelation, stk->rts_blk);
- p = BufferGetPage(b);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
- maxoff = PageGetMaxOffsetNumber(p);
-
- if (ScanDirectionIsBackward(dir))
- n = OffsetNumberPrev(stk->rts_child);
- else
- n = OffsetNumberNext(stk->rts_child);
- so->s_stack = stk->rts_parent;
- pfree(stk);
-
- n = findnext(s, p, n, dir);
- }
- if (po->flags & F_LEAF)
- {
- ItemPointerSet(&(s->currentItemData), BufferGetBlockNumber(b), n);
-
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
-
- s->xs_ctup.t_self = it->t_tid;
-
- ReleaseBuffer(b);
- return true;
- }
- else
- {
- stk = (RTSTACK *) palloc(sizeof(RTSTACK));
- stk->rts_child = n;
- stk->rts_blk = BufferGetBlockNumber(b);
- stk->rts_parent = so->s_stack;
- so->s_stack = stk;
-
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
- blk = ItemPointerGetBlockNumber(&(it->t_tid));
-
- ReleaseBuffer(b);
- b = ReadBuffer(s->indexRelation, blk);
- p = BufferGetPage(b);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
- }
- }
-}
-
-static bool
-rtnext(IndexScanDesc s, ScanDirection dir)
-{
- Buffer b;
- Page p;
- OffsetNumber n;
- OffsetNumber maxoff;
- RTreePageOpaque po;
- RTreeScanOpaque so;
- RTSTACK *stk;
- BlockNumber blk;
- IndexTuple it;
-
- blk = ItemPointerGetBlockNumber(&(s->currentItemData));
- n = ItemPointerGetOffsetNumber(&(s->currentItemData));
-
- if (ScanDirectionIsForward(dir))
- n = OffsetNumberNext(n);
- else
- n = OffsetNumberPrev(n);
-
- b = ReadBuffer(s->indexRelation, blk);
- p = BufferGetPage(b);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
- so = (RTreeScanOpaque) s->opaque;
-
- for (;;)
- {
- maxoff = PageGetMaxOffsetNumber(p);
- n = findnext(s, p, n, dir);
-
- while (n < FirstOffsetNumber || n > maxoff)
- {
- ReleaseBuffer(b);
- if (so->s_stack == (RTSTACK *) NULL)
- return false;
-
- stk = so->s_stack;
- b = ReadBuffer(s->indexRelation, stk->rts_blk);
- p = BufferGetPage(b);
- maxoff = PageGetMaxOffsetNumber(p);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
-
- if (ScanDirectionIsBackward(dir))
- n = OffsetNumberPrev(stk->rts_child);
- else
- n = OffsetNumberNext(stk->rts_child);
- so->s_stack = stk->rts_parent;
- pfree(stk);
-
- n = findnext(s, p, n, dir);
- }
- if (po->flags & F_LEAF)
- {
- ItemPointerSet(&(s->currentItemData), BufferGetBlockNumber(b), n);
-
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
-
- s->xs_ctup.t_self = it->t_tid;
-
- ReleaseBuffer(b);
- return true;
- }
- else
- {
- stk = (RTSTACK *) palloc(sizeof(RTSTACK));
- stk->rts_child = n;
- stk->rts_blk = BufferGetBlockNumber(b);
- stk->rts_parent = so->s_stack;
- so->s_stack = stk;
-
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
- blk = ItemPointerGetBlockNumber(&(it->t_tid));
-
- ReleaseBuffer(b);
- b = ReadBuffer(s->indexRelation, blk);
- p = BufferGetPage(b);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
-
- if (ScanDirectionIsBackward(dir))
- n = PageGetMaxOffsetNumber(p);
- else
- n = FirstOffsetNumber;
- }
- }
-}
-
-static OffsetNumber
-findnext(IndexScanDesc s, Page p, OffsetNumber n, ScanDirection dir)
-{
- OffsetNumber maxoff;
- IndexTuple it;
- RTreePageOpaque po;
- RTreeScanOpaque so;
-
- maxoff = PageGetMaxOffsetNumber(p);
- po = (RTreePageOpaque) PageGetSpecialPointer(p);
- so = (RTreeScanOpaque) s->opaque;
-
- /*
- * If we modified the index during the scan, we may have a pointer to
- * a ghost tuple, before the scan. If this is the case, back up one.
- */
-
- if (so->s_flags & RTS_CURBEFORE)
- {
- so->s_flags &= ~RTS_CURBEFORE;
- n = OffsetNumberPrev(n);
- }
-
- while (n >= FirstOffsetNumber && n <= maxoff)
- {
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
- if (po->flags & F_LEAF)
- {
- if (index_keytest(it,
- RelationGetDescr(s->indexRelation),
- s->numberOfKeys, s->keyData))
- break;
- }
- else
- {
- if (index_keytest(it,
- RelationGetDescr(s->indexRelation),
- so->s_internalNKey, so->s_internalKey))
- break;
- }
-
- if (ScanDirectionIsBackward(dir))
- n = OffsetNumberPrev(n);
- else
- n = OffsetNumberNext(n);
- }
-
- return n;
-}
-
-static bool
-rtscancache(IndexScanDesc s, ScanDirection dir)
-{
- Buffer b;
- Page p;
- OffsetNumber n;
- IndexTuple it;
-
- if (!(ScanDirectionIsNoMovement(dir)
- && ItemPointerIsValid(&(s->currentItemData))))
- return false;
-
- b = ReadBuffer(s->indexRelation,
- ItemPointerGetBlockNumber(&(s->currentItemData)));
- p = BufferGetPage(b);
- n = ItemPointerGetOffsetNumber(&(s->currentItemData));
- it = (IndexTuple) PageGetItem(p, PageGetItemId(p, n));
- s->xs_ctup.t_self = it->t_tid;
- ReleaseBuffer(b);
-
- return true;
-}
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