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-rw-r--r--src/backend/access/rtree/rtree.c955
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diff --git a/src/backend/access/rtree/rtree.c b/src/backend/access/rtree/rtree.c
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+/*-------------------------------------------------------------------------
+ *
+ * rtree.c--
+ * interface routines for the postgres rtree indexed access method.
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * $Header: /cvsroot/pgsql/src/backend/access/rtree/Attic/rtree.c,v 1.1.1.1 1996/07/09 06:21:13 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "storage/bufmgr.h"
+#include "storage/bufpage.h"
+
+#include "utils/elog.h"
+#include "utils/palloc.h"
+#include "utils/rel.h"
+#include "utils/excid.h"
+
+#include "access/heapam.h"
+#include "access/genam.h"
+#include "access/rtree.h"
+#include "access/rtscan.h"
+#include "access/funcindex.h"
+#include "access/tupdesc.h"
+
+#include "nodes/execnodes.h"
+#include "nodes/plannodes.h"
+
+#include "executor/executor.h"
+#include "executor/tuptable.h"
+
+#include "catalog/index.h"
+
+typedef struct SPLITVEC {
+ OffsetNumber *spl_left;
+ int spl_nleft;
+ char *spl_ldatum;
+ OffsetNumber *spl_right;
+ int spl_nright;
+ char *spl_rdatum;
+} SPLITVEC;
+
+typedef struct RTSTATE {
+ func_ptr unionFn; /* union function */
+ func_ptr sizeFn; /* size function */
+ func_ptr interFn; /* intersection function */
+} RTSTATE;
+
+/* non-export function prototypes */
+static InsertIndexResult rtdoinsert(Relation r, IndexTuple itup,
+ RTSTATE *rtstate);
+static void rttighten(Relation r, RTSTACK *stk, char *datum, int att_size,
+ RTSTATE *rtstate);
+static InsertIndexResult dosplit(Relation r, Buffer buffer, RTSTACK *stack,
+ IndexTuple itup, RTSTATE *rtstate);
+static void rtintinsert(Relation r, RTSTACK *stk, IndexTuple ltup,
+ IndexTuple rtup, RTSTATE *rtstate);
+static void rtnewroot(Relation r, IndexTuple lt, IndexTuple rt);
+static void picksplit(Relation r, Page page, SPLITVEC *v, IndexTuple itup,
+ RTSTATE *rtstate);
+static void RTInitBuffer(Buffer b, uint32 f);
+static OffsetNumber choose(Relation r, Page p, IndexTuple it,
+ RTSTATE *rtstate);
+static int nospace(Page p, IndexTuple it);
+static void initRtstate(RTSTATE *rtstate, Relation index);
+
+
+void
+rtbuild(Relation heap,
+ Relation index,
+ int natts,
+ AttrNumber *attnum,
+ IndexStrategy istrat,
+ uint16 pcount,
+ Datum *params,
+ FuncIndexInfo *finfo,
+ PredInfo *predInfo)
+{
+ HeapScanDesc scan;
+ Buffer buffer;
+ AttrNumber i;
+ HeapTuple htup;
+ IndexTuple itup;
+ TupleDesc hd, id;
+ InsertIndexResult res;
+ Datum *d;
+ bool *nulls;
+ int nb, nh, ni;
+ ExprContext *econtext;
+ TupleTable tupleTable;
+ TupleTableSlot *slot;
+ Oid hrelid, irelid;
+ Node *pred, *oldPred;
+ RTSTATE rtState;
+
+ initRtstate(&rtState, index);
+
+ /* rtrees only know how to do stupid locking now */
+ RelationSetLockForWrite(index);
+
+ pred = predInfo->pred;
+ oldPred = predInfo->oldPred;
+
+ /*
+ * We expect to be called exactly once for any index relation.
+ * If that's not the case, big trouble's what we have.
+ */
+
+ if (oldPred == NULL && (nb = RelationGetNumberOfBlocks(index)) != 0)
+ elog(WARN, "%s already contains data", index->rd_rel->relname.data);
+
+ /* initialize the root page (if this is a new index) */
+ if (oldPred == NULL) {
+ buffer = ReadBuffer(index, P_NEW);
+ RTInitBuffer(buffer, F_LEAF);
+ WriteBuffer(buffer);
+ }
+
+ /* init the tuple descriptors and get set for a heap scan */
+ hd = RelationGetTupleDescriptor(heap);
+ id = RelationGetTupleDescriptor(index);
+ d = (Datum *)palloc(natts * sizeof (*d));
+ nulls = (bool *)palloc(natts * sizeof (*nulls));
+
+ /*
+ * If this is a predicate (partial) index, we will need to evaluate the
+ * predicate using ExecQual, which requires the current tuple to be in a
+ * slot of a TupleTable. In addition, ExecQual must have an ExprContext
+ * referring to that slot. Here, we initialize dummy TupleTable and
+ * ExprContext objects for this purpose. --Nels, Feb '92
+ */
+#ifndef OMIT_PARTIAL_INDEX
+ if (pred != NULL || oldPred != NULL) {
+ tupleTable = ExecCreateTupleTable(1);
+ slot = ExecAllocTableSlot(tupleTable);
+ econtext = makeNode(ExprContext);
+ FillDummyExprContext(econtext, slot, hd, buffer);
+ }
+#endif /* OMIT_PARTIAL_INDEX */
+ scan = heap_beginscan(heap, 0, NowTimeQual, 0, (ScanKey) NULL);
+ htup = heap_getnext(scan, 0, &buffer);
+
+ /* count the tuples as we insert them */
+ nh = ni = 0;
+
+ for (; HeapTupleIsValid(htup); htup = heap_getnext(scan, 0, &buffer)) {
+
+ nh++;
+
+ /*
+ * If oldPred != NULL, this is an EXTEND INDEX command, so skip
+ * this tuple if it was already in the existing partial index
+ */
+ if (oldPred != NULL) {
+#ifndef OMIT_PARTIAL_INDEX
+ /*SetSlotContents(slot, htup); */
+ slot->val = htup;
+ if (ExecQual((List*)oldPred, econtext) == true) {
+ ni++;
+ continue;
+ }
+#endif /* OMIT_PARTIAL_INDEX */
+ }
+
+ /* Skip this tuple if it doesn't satisfy the partial-index predicate */
+ if (pred != NULL) {
+#ifndef OMIT_PARTIAL_INDEX
+ /*SetSlotContents(slot, htup); */
+ slot->val = htup;
+ if (ExecQual((List*)pred, econtext) == false)
+ continue;
+#endif /* OMIT_PARTIAL_INDEX */
+ }
+
+ ni++;
+
+ /*
+ * For the current heap tuple, extract all the attributes
+ * we use in this index, and note which are null.
+ */
+
+ for (i = 1; i <= natts; i++) {
+ int attoff;
+ bool attnull;
+
+ /*
+ * Offsets are from the start of the tuple, and are
+ * zero-based; indices are one-based. The next call
+ * returns i - 1. That's data hiding for you.
+ */
+
+ attoff = AttrNumberGetAttrOffset(i);
+ /*
+ d[attoff] = HeapTupleGetAttributeValue(htup, buffer,
+ */
+ d[attoff] = GetIndexValue(htup,
+ hd,
+ attoff,
+ attnum,
+ finfo,
+ &attnull,
+ buffer);
+ nulls[attoff] = (attnull ? 'n' : ' ');
+ }
+
+ /* form an index tuple and point it at the heap tuple */
+ itup = index_formtuple(id, &d[0], nulls);
+ itup->t_tid = htup->t_ctid;
+
+ /*
+ * Since we already have the index relation locked, we
+ * call rtdoinsert directly. Normal access method calls
+ * dispatch through rtinsert, which locks the relation
+ * for write. This is the right thing to do if you're
+ * inserting single tups, but not when you're initializing
+ * the whole index at once.
+ */
+
+ res = rtdoinsert(index, itup, &rtState);
+ pfree(itup);
+ pfree(res);
+ }
+
+ /* okay, all heap tuples are indexed */
+ heap_endscan(scan);
+ RelationUnsetLockForWrite(index);
+
+ if (pred != NULL || oldPred != NULL) {
+#ifndef OMIT_PARTIAL_INDEX
+ ExecDestroyTupleTable(tupleTable, true);
+ pfree(econtext);
+#endif /* OMIT_PARTIAL_INDEX */
+ }
+
+ /*
+ * Since we just counted the tuples in the heap, we update its
+ * stats in pg_relation to guarantee that the planner takes
+ * advantage of the index we just created. UpdateStats() does a
+ * CommandCounterIncrement(), which flushes changed entries from
+ * the system relcache. The act of constructing an index changes
+ * these heap and index tuples in the system catalogs, so they
+ * need to be flushed. We close them to guarantee that they
+ * will be.
+ */
+
+ hrelid = heap->rd_id;
+ irelid = index->rd_id;
+ heap_close(heap);
+ index_close(index);
+
+ UpdateStats(hrelid, nh, true);
+ UpdateStats(irelid, ni, false);
+
+ if (oldPred != NULL) {
+ if (ni == nh) pred = NULL;
+ UpdateIndexPredicate(irelid, oldPred, pred);
+ }
+
+ /* be tidy */
+ pfree(nulls);
+ pfree(d);
+}
+
+/*
+ * rtinsert -- wrapper for rtree tuple insertion.
+ *
+ * This is the public interface routine for tuple insertion in rtrees.
+ * It doesn't do any work; just locks the relation and passes the buck.
+ */
+InsertIndexResult
+rtinsert(Relation r, IndexTuple itup)
+{
+ InsertIndexResult res;
+ RTSTATE rtState;
+
+ initRtstate(&rtState, r);
+
+ RelationSetLockForWrite(r);
+ res = rtdoinsert(r, itup, &rtState);
+
+ /* XXX two-phase locking -- don't unlock the relation until EOT */
+ return (res);
+}
+
+static InsertIndexResult
+rtdoinsert(Relation r, IndexTuple itup, RTSTATE *rtstate)
+{
+ Page page;
+ Buffer buffer;
+ BlockNumber blk;
+ IndexTuple which;
+ OffsetNumber l;
+ RTSTACK *stack;
+ InsertIndexResult res;
+ RTreePageOpaque opaque;
+ char *datum;
+
+ blk = P_ROOT;
+ buffer = InvalidBuffer;
+ stack = (RTSTACK *) NULL;
+
+ do {
+ /* let go of current buffer before getting next */
+ if (buffer != InvalidBuffer)
+ ReleaseBuffer(buffer);
+
+ /* get next buffer */
+ buffer = ReadBuffer(r, blk);
+ page = (Page) BufferGetPage(buffer);
+
+ opaque = (RTreePageOpaque) PageGetSpecialPointer(page);
+ if (!(opaque->flags & F_LEAF)) {
+ RTSTACK *n;
+ ItemId iid;
+
+ n = (RTSTACK *) palloc(sizeof(RTSTACK));
+ n->rts_parent = stack;
+ n->rts_blk = blk;
+ n->rts_child = choose(r, page, itup, rtstate);
+ stack = n;
+
+ iid = PageGetItemId(page, n->rts_child);
+ which = (IndexTuple) PageGetItem(page, iid);
+ blk = ItemPointerGetBlockNumber(&(which->t_tid));
+ }
+ } while (!(opaque->flags & F_LEAF));
+
+ if (nospace(page, itup)) {
+ /* need to do a split */
+ res = dosplit(r, buffer, stack, itup, rtstate);
+ freestack(stack);
+ WriteBuffer(buffer); /* don't forget to release buffer! */
+ return (res);
+ }
+
+ /* add the item and write the buffer */
+ if (PageIsEmpty(page)) {
+ l = PageAddItem(page, (Item) itup, IndexTupleSize(itup),
+ FirstOffsetNumber,
+ LP_USED);
+ } else {
+ l = PageAddItem(page, (Item) itup, IndexTupleSize(itup),
+ OffsetNumberNext(PageGetMaxOffsetNumber(page)),
+ LP_USED);
+ }
+
+ WriteBuffer(buffer);
+
+ datum = (((char *) itup) + sizeof(IndexTupleData));
+
+ /* now expand the page boundary in the parent to include the new child */
+ rttighten(r, stack, datum,
+ (IndexTupleSize(itup) - sizeof(IndexTupleData)), rtstate);
+ freestack(stack);
+
+ /* build and return an InsertIndexResult for this insertion */
+ res = (InsertIndexResult) palloc(sizeof(InsertIndexResultData));
+ ItemPointerSet(&(res->pointerData), blk, l);
+
+ return (res);
+}
+
+static void
+rttighten(Relation r,
+ RTSTACK *stk,
+ char *datum,
+ int att_size,
+ RTSTATE *rtstate)
+{
+ char *oldud;
+ char *tdatum;
+ Page p;
+ float old_size, newd_size;
+ Buffer b;
+
+ if (stk == (RTSTACK *) NULL)
+ return;
+
+ b = ReadBuffer(r, stk->rts_blk);
+ p = BufferGetPage(b);
+
+ oldud = (char *) PageGetItem(p, PageGetItemId(p, stk->rts_child));
+ oldud += sizeof(IndexTupleData);
+
+ (*rtstate->sizeFn)(oldud, &old_size);
+ datum = (char *) (*rtstate->unionFn)(oldud, datum);
+
+ (*rtstate->sizeFn)(datum, &newd_size);
+
+ if (newd_size != old_size) {
+ TupleDesc td = RelationGetTupleDescriptor(r);
+
+ if (td->attrs[0]->attlen < 0) {
+ /*
+ * This is an internal page, so 'oldud' had better be a
+ * union (constant-length) key, too. (See comment below.)
+ */
+ Assert(VARSIZE(datum) == VARSIZE(oldud));
+ memmove(oldud, datum, VARSIZE(datum));
+ } else {
+ memmove(oldud, datum, att_size);
+ }
+ WriteBuffer(b);
+
+ /*
+ * The user may be defining an index on variable-sized data (like
+ * polygons). If so, we need to get a constant-sized datum for
+ * insertion on the internal page. We do this by calling the union
+ * proc, which is guaranteed to return a rectangle.
+ */
+
+ tdatum = (char *) (*rtstate->unionFn)(datum, datum);
+ rttighten(r, stk->rts_parent, tdatum, att_size, rtstate);
+ pfree(tdatum);
+ } else {
+ ReleaseBuffer(b);
+ }
+ pfree(datum);
+}
+
+/*
+ * dosplit -- split a page in the tree.
+ *
+ * This is the quadratic-cost split algorithm Guttman describes in
+ * his paper. The reason we chose it is that you can implement this
+ * with less information about the data types on which you're operating.
+ */
+static InsertIndexResult
+dosplit(Relation r,
+ Buffer buffer,
+ RTSTACK *stack,
+ IndexTuple itup,
+ RTSTATE *rtstate)
+{
+ Page p;
+ Buffer leftbuf, rightbuf;
+ Page left, right;
+ ItemId itemid;
+ IndexTuple item;
+ IndexTuple ltup, rtup;
+ OffsetNumber maxoff;
+ OffsetNumber i;
+ OffsetNumber leftoff, rightoff;
+ BlockNumber lbknum, rbknum;
+ BlockNumber bufblock;
+ RTreePageOpaque opaque;
+ int blank;
+ InsertIndexResult res;
+ char *isnull;
+ SPLITVEC v;
+ TupleDesc tupDesc;
+
+ isnull = (char *) palloc(r->rd_rel->relnatts);
+ for (blank = 0; blank < r->rd_rel->relnatts; blank++)
+ isnull[blank] = ' ';
+ p = (Page) BufferGetPage(buffer);
+ opaque = (RTreePageOpaque) PageGetSpecialPointer(p);
+
+ /*
+ * The root of the tree is the first block in the relation. If
+ * we're about to split the root, we need to do some hocus-pocus
+ * to enforce this guarantee.
+ */
+
+ if (BufferGetBlockNumber(buffer) == P_ROOT) {
+ leftbuf = ReadBuffer(r, P_NEW);
+ RTInitBuffer(leftbuf, opaque->flags);
+ lbknum = BufferGetBlockNumber(leftbuf);
+ left = (Page) BufferGetPage(leftbuf);
+ } else {
+ leftbuf = buffer;
+ IncrBufferRefCount(buffer);
+ lbknum = BufferGetBlockNumber(buffer);
+ left = (Page) PageGetTempPage(p, sizeof(RTreePageOpaqueData));
+ }
+
+ rightbuf = ReadBuffer(r, P_NEW);
+ RTInitBuffer(rightbuf, opaque->flags);
+ rbknum = BufferGetBlockNumber(rightbuf);
+ right = (Page) BufferGetPage(rightbuf);
+
+ picksplit(r, p, &v, itup, rtstate);
+
+ leftoff = rightoff = FirstOffsetNumber;
+ maxoff = PageGetMaxOffsetNumber(p);
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i)) {
+ itemid = PageGetItemId(p, i);
+ item = (IndexTuple) PageGetItem(p, itemid);
+
+ if (i == *(v.spl_left)) {
+ (void) PageAddItem(left, (Item) item, IndexTupleSize(item),
+ leftoff, LP_USED);
+ leftoff = OffsetNumberNext(leftoff);
+ v.spl_left++; /* advance in left split vector */
+ } else {
+ (void) PageAddItem(right, (Item) item, IndexTupleSize(item),
+ rightoff, LP_USED);
+ rightoff = OffsetNumberNext(rightoff);
+ v.spl_right++; /* advance in right split vector */
+ }
+ }
+
+ /* build an InsertIndexResult for this insertion */
+ res = (InsertIndexResult) palloc(sizeof(InsertIndexResultData));
+
+ /* now insert the new index tuple */
+ if (*(v.spl_left) != FirstOffsetNumber) {
+ (void) PageAddItem(left, (Item) itup, IndexTupleSize(itup),
+ leftoff, LP_USED);
+ leftoff = OffsetNumberNext(leftoff);
+ ItemPointerSet(&(res->pointerData), lbknum, leftoff);
+ } else {
+ (void) PageAddItem(right, (Item) itup, IndexTupleSize(itup),
+ rightoff, LP_USED);
+ rightoff = OffsetNumberNext(rightoff);
+ ItemPointerSet(&(res->pointerData), rbknum, rightoff);
+ }
+
+ if ((bufblock = BufferGetBlockNumber(buffer)) != P_ROOT) {
+ PageRestoreTempPage(left, p);
+ }
+ WriteBuffer(leftbuf);
+ WriteBuffer(rightbuf);
+
+ /*
+ * Okay, the page is split. We have three things left to do:
+ *
+ * 1) Adjust any active scans on this index to cope with changes
+ * we introduced in its structure by splitting this page.
+ *
+ * 2) "Tighten" the bounding box of the pointer to the left
+ * page in the parent node in the tree, if any. Since we
+ * moved a bunch of stuff off the left page, we expect it
+ * to get smaller. This happens in the internal insertion
+ * routine.
+ *
+ * 3) Insert a pointer to the right page in the parent. This
+ * may cause the parent to split. If it does, we need to
+ * repeat steps one and two for each split node in the tree.
+ */
+
+ /* adjust active scans */
+ rtadjscans(r, RTOP_SPLIT, bufblock, FirstOffsetNumber);
+
+ tupDesc = r->rd_att;
+ ltup = (IndexTuple) index_formtuple(tupDesc,
+ (Datum *) &(v.spl_ldatum), isnull);
+ rtup = (IndexTuple) index_formtuple(tupDesc,
+ (Datum *) &(v.spl_rdatum), isnull);
+ pfree(isnull);
+
+ /* set pointers to new child pages in the internal index tuples */
+ ItemPointerSet(&(ltup->t_tid), lbknum, 1);
+ ItemPointerSet(&(rtup->t_tid), rbknum, 1);
+
+ rtintinsert(r, stack, ltup, rtup, rtstate);
+
+ pfree(ltup);
+ pfree(rtup);
+
+ return (res);
+}
+
+static void
+rtintinsert(Relation r,
+ RTSTACK *stk,
+ IndexTuple ltup,
+ IndexTuple rtup,
+ RTSTATE *rtstate)
+{
+ IndexTuple old;
+ Buffer b;
+ Page p;
+ char *ldatum, *rdatum, *newdatum;
+ InsertIndexResult res;
+
+ if (stk == (RTSTACK *) NULL) {
+ rtnewroot(r, ltup, rtup);
+ return;
+ }
+
+ b = ReadBuffer(r, stk->rts_blk);
+ p = BufferGetPage(b);
+ old = (IndexTuple) PageGetItem(p, PageGetItemId(p, stk->rts_child));
+
+ /*
+ * This is a hack. Right now, we force rtree keys to be constant size.
+ * To fix this, need delete the old key and add both left and right
+ * for the two new pages. The insertion of left may force a split if
+ * the new left key is bigger than the old key.
+ */
+
+ if (IndexTupleSize(old) != IndexTupleSize(ltup))
+ elog(WARN, "Variable-length rtree keys are not supported.");
+
+ /* install pointer to left child */
+ memmove(old, ltup,IndexTupleSize(ltup));
+
+ if (nospace(p, rtup)) {
+ newdatum = (((char *) ltup) + sizeof(IndexTupleData));
+ rttighten(r, stk->rts_parent, newdatum,
+ (IndexTupleSize(ltup) - sizeof(IndexTupleData)), rtstate);
+ res = dosplit(r, b, stk->rts_parent, rtup, rtstate);
+ WriteBuffer(b); /* don't forget to release buffer! - 01/31/94 */
+ pfree(res);
+ } else {
+ (void) PageAddItem(p, (Item) rtup, IndexTupleSize(rtup),
+ PageGetMaxOffsetNumber(p), LP_USED);
+ WriteBuffer(b);
+ ldatum = (((char *) ltup) + sizeof(IndexTupleData));
+ rdatum = (((char *) rtup) + sizeof(IndexTupleData));
+ newdatum = (char *) (*rtstate->unionFn)(ldatum, rdatum);
+
+ rttighten(r, stk->rts_parent, newdatum,
+ (IndexTupleSize(rtup) - sizeof(IndexTupleData)), rtstate);
+
+ pfree(newdatum);
+ }
+}
+
+static void
+rtnewroot(Relation r, IndexTuple lt, IndexTuple rt)
+{
+ Buffer b;
+ Page p;
+
+ b = ReadBuffer(r, P_ROOT);
+ RTInitBuffer(b, 0);
+ p = BufferGetPage(b);
+ (void) PageAddItem(p, (Item) lt, IndexTupleSize(lt),
+ FirstOffsetNumber, LP_USED);
+ (void) PageAddItem(p, (Item) rt, IndexTupleSize(rt),
+ OffsetNumberNext(FirstOffsetNumber), LP_USED);
+ WriteBuffer(b);
+}
+
+static void
+picksplit(Relation r,
+ Page page,
+ SPLITVEC *v,
+ IndexTuple itup,
+ RTSTATE *rtstate)
+{
+ OffsetNumber maxoff;
+ OffsetNumber i, j;
+ IndexTuple item_1, item_2;
+ char *datum_alpha, *datum_beta;
+ char *datum_l, *datum_r;
+ char *union_d, *union_dl, *union_dr;
+ char *inter_d;
+ bool firsttime;
+ float size_alpha, size_beta, size_union, size_inter;
+ float size_waste, waste;
+ float size_l, size_r;
+ int nbytes;
+ OffsetNumber seed_1 = 0, seed_2 = 0;
+ OffsetNumber *left, *right;
+
+ maxoff = PageGetMaxOffsetNumber(page);
+
+ nbytes = (maxoff + 2) * sizeof(OffsetNumber);
+ v->spl_left = (OffsetNumber *) palloc(nbytes);
+ v->spl_right = (OffsetNumber *) palloc(nbytes);
+
+ firsttime = true;
+ waste = 0.0;
+
+ for (i = FirstOffsetNumber; i < maxoff; i = OffsetNumberNext(i)) {
+ item_1 = (IndexTuple) PageGetItem(page, PageGetItemId(page, i));
+ datum_alpha = ((char *) item_1) + sizeof(IndexTupleData);
+ for (j = OffsetNumberNext(i); j <= maxoff; j = OffsetNumberNext(j)) {
+ item_2 = (IndexTuple) PageGetItem(page, PageGetItemId(page, j));
+ datum_beta = ((char *) item_2) + sizeof(IndexTupleData);
+
+ /* compute the wasted space by unioning these guys */
+ union_d = (char *)(rtstate->unionFn)(datum_alpha, datum_beta);
+ (rtstate->sizeFn)(union_d, &size_union);
+ inter_d = (char *)(rtstate->interFn)(datum_alpha, datum_beta);
+ (rtstate->sizeFn)(inter_d, &size_inter);
+ size_waste = size_union - size_inter;
+
+ pfree(union_d);
+
+ if (inter_d != (char *) NULL)
+ pfree(inter_d);
+
+ /*
+ * are these a more promising split that what we've
+ * already seen?
+ */
+
+ if (size_waste > waste || firsttime) {
+ waste = size_waste;
+ seed_1 = i;
+ seed_2 = j;
+ firsttime = false;
+ }
+ }
+ }
+
+ left = v->spl_left;
+ v->spl_nleft = 0;
+ right = v->spl_right;
+ v->spl_nright = 0;
+
+ item_1 = (IndexTuple) PageGetItem(page, PageGetItemId(page, seed_1));
+ datum_alpha = ((char *) item_1) + sizeof(IndexTupleData);
+ datum_l = (char *)(*rtstate->unionFn)(datum_alpha, datum_alpha);
+ (*rtstate->sizeFn)(datum_l, &size_l);
+ item_2 = (IndexTuple) PageGetItem(page, PageGetItemId(page, seed_2));
+ datum_beta = ((char *) item_2) + sizeof(IndexTupleData);
+ datum_r = (char *)(*rtstate->unionFn)(datum_beta, datum_beta);
+ (*rtstate->sizeFn)(datum_r, &size_r);
+
+ /*
+ * Now split up the regions between the two seeds. An important
+ * property of this split algorithm is that the split vector v
+ * has the indices of items to be split in order in its left and
+ * right vectors. We exploit this property by doing a merge in
+ * the code that actually splits the page.
+ *
+ * For efficiency, we also place the new index tuple in this loop.
+ * This is handled at the very end, when we have placed all the
+ * existing tuples and i == maxoff + 1.
+ */
+
+ maxoff = OffsetNumberNext(maxoff);
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i)) {
+
+ /*
+ * If we've already decided where to place this item, just
+ * put it on the right list. Otherwise, we need to figure
+ * out which page needs the least enlargement in order to
+ * store the item.
+ */
+
+ if (i == seed_1) {
+ *left++ = i;
+ v->spl_nleft++;
+ continue;
+ } else if (i == seed_2) {
+ *right++ = i;
+ v->spl_nright++;
+ continue;
+ }
+
+ /* okay, which page needs least enlargement? */
+ if (i == maxoff) {
+ item_1 = itup;
+ } else {
+ item_1 = (IndexTuple) PageGetItem(page, PageGetItemId(page, i));
+ }
+
+ datum_alpha = ((char *) item_1) + sizeof(IndexTupleData);
+ union_dl = (char *)(*rtstate->unionFn)(datum_l, datum_alpha);
+ union_dr = (char *)(*rtstate->unionFn)(datum_r, datum_alpha);
+ (*rtstate->sizeFn)(union_dl, &size_alpha);
+ (*rtstate->sizeFn)(union_dr, &size_beta);
+
+ /* pick which page to add it to */
+ if (size_alpha - size_l < size_beta - size_r) {
+ pfree(datum_l);
+ pfree(union_dr);
+ datum_l = union_dl;
+ size_l = size_alpha;
+ *left++ = i;
+ v->spl_nleft++;
+ } else {
+ pfree(datum_r);
+ pfree(union_dl);
+ datum_r = union_dr;
+ size_r = size_alpha;
+ *right++ = i;
+ v->spl_nright++;
+ }
+ }
+ *left = *right = FirstOffsetNumber; /* sentinel value, see dosplit() */
+
+ v->spl_ldatum = datum_l;
+ v->spl_rdatum = datum_r;
+}
+
+static void
+RTInitBuffer(Buffer b, uint32 f)
+{
+ RTreePageOpaque opaque;
+ Page page;
+ Size pageSize;
+
+ pageSize = BufferGetPageSize(b);
+
+ page = BufferGetPage(b);
+ memset(page, 0, (int) pageSize);
+ PageInit(page, pageSize, sizeof(RTreePageOpaqueData));
+
+ opaque = (RTreePageOpaque) PageGetSpecialPointer(page);
+ opaque->flags = f;
+}
+
+static OffsetNumber
+choose(Relation r, Page p, IndexTuple it, RTSTATE *rtstate)
+{
+ OffsetNumber maxoff;
+ OffsetNumber i;
+ char *ud, *id;
+ char *datum;
+ float usize, dsize;
+ OffsetNumber which;
+ float which_grow;
+
+ id = ((char *) it) + sizeof(IndexTupleData);
+ maxoff = PageGetMaxOffsetNumber(p);
+ which_grow = -1.0;
+ which = -1;
+
+ for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i)) {
+ datum = (char *) PageGetItem(p, PageGetItemId(p, i));
+ datum += sizeof(IndexTupleData);
+ (*rtstate->sizeFn)(datum, &dsize);
+ ud = (char *) (*rtstate->unionFn)(datum, id);
+ (*rtstate->sizeFn)(ud, &usize);
+ pfree(ud);
+ if (which_grow < 0 || usize - dsize < which_grow) {
+ which = i;
+ which_grow = usize - dsize;
+ if (which_grow == 0)
+ break;
+ }
+ }
+
+ return (which);
+}
+
+static int
+nospace(Page p, IndexTuple it)
+{
+ return (PageGetFreeSpace(p) < IndexTupleSize(it));
+}
+
+void
+freestack(RTSTACK *s)
+{
+ RTSTACK *p;
+
+ while (s != (RTSTACK *) NULL) {
+ p = s->rts_parent;
+ pfree(s);
+ s = p;
+ }
+}
+
+char *
+rtdelete(Relation r, ItemPointer tid)
+{
+ BlockNumber blkno;
+ OffsetNumber offnum;
+ Buffer buf;
+ Page page;
+
+ /* must write-lock on delete */
+ RelationSetLockForWrite(r);
+
+ blkno = ItemPointerGetBlockNumber(tid);
+ offnum = ItemPointerGetOffsetNumber(tid);
+
+ /* adjust any scans that will be affected by this deletion */
+ rtadjscans(r, RTOP_DEL, blkno, offnum);
+
+ /* delete the index tuple */
+ buf = ReadBuffer(r, blkno);
+ page = BufferGetPage(buf);
+
+ PageIndexTupleDelete(page, offnum);
+
+ WriteBuffer(buf);
+
+ /* XXX -- two-phase locking, don't release the write lock */
+ return ((char *) NULL);
+}
+
+static void initRtstate(RTSTATE *rtstate, Relation index)
+{
+ RegProcedure union_proc, size_proc, inter_proc;
+ func_ptr user_fn;
+ int pronargs;
+
+ union_proc = index_getprocid(index, 1, RT_UNION_PROC);
+ size_proc = index_getprocid(index, 1, RT_SIZE_PROC);
+ inter_proc = index_getprocid(index, 1, RT_INTER_PROC);
+ fmgr_info(union_proc, &user_fn, &pronargs);
+ rtstate->unionFn = user_fn;
+ fmgr_info(size_proc, &user_fn, &pronargs);
+ rtstate->sizeFn = user_fn;
+ fmgr_info(inter_proc, &user_fn, &pronargs);
+ rtstate->interFn = user_fn;
+ return;
+}
+
+#define RTDEBUG
+#ifdef RTDEBUG
+#include "utils/geo-decls.h"
+
+void
+_rtdump(Relation r)
+{
+ Buffer buf;
+ Page page;
+ OffsetNumber offnum, maxoff;
+ BlockNumber blkno;
+ BlockNumber nblocks;
+ RTreePageOpaque po;
+ IndexTuple itup;
+ BlockNumber itblkno;
+ OffsetNumber itoffno;
+ char *datum;
+ char *itkey;
+
+ nblocks = RelationGetNumberOfBlocks(r);
+ for (blkno = 0; blkno < nblocks; blkno++) {
+ buf = ReadBuffer(r, blkno);
+ page = BufferGetPage(buf);
+ po = (RTreePageOpaque) PageGetSpecialPointer(page);
+ maxoff = PageGetMaxOffsetNumber(page);
+ printf("Page %d maxoff %d <%s>\n", blkno, maxoff,
+ (po->flags & F_LEAF ? "LEAF" : "INTERNAL"));
+
+ if (PageIsEmpty(page)) {
+ ReleaseBuffer(buf);
+ continue;
+ }
+
+ for (offnum = FirstOffsetNumber;
+ offnum <= maxoff;
+ offnum = OffsetNumberNext(offnum)) {
+ itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, offnum));
+ itblkno = ItemPointerGetBlockNumber(&(itup->t_tid));
+ itoffno = ItemPointerGetOffsetNumber(&(itup->t_tid));
+ datum = ((char *) itup);
+ datum += sizeof(IndexTupleData);
+ itkey = (char *) box_out((BOX *) datum);
+ printf("\t[%d] size %d heap <%d,%d> key:%s\n",
+ offnum, IndexTupleSize(itup), itblkno, itoffno, itkey);
+ pfree(itkey);
+ }
+
+ ReleaseBuffer(buf);
+ }
+}
+#endif /* defined RTDEBUG */
+
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-19 15:04:16 +0000