/*-------------------------------------------------------------------------
*
* gist.c
* interface routines for the postgres GiST index access method.
*
*
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.118 2005/06/06 17:01:21 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/gist_private.h"
#include "access/gistscan.h"
#include "access/heapam.h"
#include "catalog/index.h"
#include "commands/vacuum.h"
#include "miscadmin.h"
#include "utils/memutils.h"
#undef GIST_PAGEADDITEM
#define ATTSIZE(datum, tupdesc, i, isnull) \
( \
(isnull) ? 0 : \
att_addlength(0, (tupdesc)->attrs[(i)-1]->attlen, (datum)) \
)
/* result's status */
#define INSERTED 0x01
#define SPLITED 0x02
/* group flags ( in gistSplit ) */
#define LEFT_ADDED 0x01
#define RIGHT_ADDED 0x02
#define BOTH_ADDED ( LEFT_ADDED | RIGHT_ADDED )
/*
* This defines only for shorter code, used in gistgetadjusted
* and gistadjsubkey only
*/
#define FILLITEM(evp, isnullkey, okey, okeyb, rkey, rkeyb) do { \
if (isnullkey) { \
gistentryinit((evp), rkey, r, NULL, \
(OffsetNumber) 0, rkeyb, FALSE); \
} else { \
gistentryinit((evp), okey, r, NULL, \
(OffsetNumber) 0, okeyb, FALSE); \
} \
} while(0)
#define FILLEV(isnull1, key1, key1b, isnull2, key2, key2b) do { \
FILLITEM(*ev0p, isnull1, key1, key1b, key2, key2b); \
FILLITEM(*ev1p, isnull2, key2, key2b, key1, key1b); \
} while(0);
/* Working state for gistbuild and its callback */
typedef struct
{
GISTSTATE giststate;
int numindexattrs;
double indtuples;
MemoryContext tmpCxt;
} GISTBuildState;
/* non-export function prototypes */
static void gistbuildCallback(Relation index,
HeapTuple htup,
Datum *values,
bool *isnull,
bool tupleIsAlive,
void *state);
static void gistdoinsert(Relation r,
IndexTuple itup,
GISTSTATE *GISTstate);
static int gistlayerinsert(Relation r, BlockNumber blkno,
IndexTuple **itup,
int *len,
GISTSTATE *giststate);
static OffsetNumber gistwritebuffer(Relation r,
Page page,
IndexTuple *itup,
int len,
OffsetNumber off);
static bool gistnospace(Page page, IndexTuple *itvec, int len);
static IndexTuple *gistreadbuffer(Buffer buffer, int *len);
static IndexTuple *gistjoinvector(
IndexTuple *itvec, int *len,
IndexTuple *additvec, int addlen);
static IndexTuple gistunion(Relation r, IndexTuple *itvec,
int len, GISTSTATE *giststate);
static IndexTuple gistgetadjusted(Relation r,
IndexTuple oldtup,
IndexTuple addtup,
GISTSTATE *giststate);
static int gistfindgroup(GISTSTATE *giststate,
GISTENTRY *valvec, GIST_SPLITVEC *spl);
static void gistadjsubkey(Relation r,
IndexTuple *itup, int *len,
GIST_SPLITVEC *v,
GISTSTATE *giststate);
static IndexTuple gistFormTuple(GISTSTATE *giststate,
Relation r, Datum *attdata, int *datumsize, bool *isnull);
static IndexTuple *gistSplit(Relation r,
Buffer buffer,
IndexTuple *itup,
int *len,
GISTSTATE *giststate);
static void gistnewroot(Relation r, IndexTuple *itup, int len);
static void GISTInitBuffer(Buffer b, uint32 f);
static OffsetNumber gistchoose(Relation r, Page p,
IndexTuple it,
GISTSTATE *giststate);
static void gistdelete(Relation r, ItemPointer tid);
#ifdef GIST_PAGEADDITEM
static IndexTuple gist_tuple_replacekey(Relation r,
GISTENTRY entry, IndexTuple t);
#endif
static void gistcentryinit(GISTSTATE *giststate, int nkey,
GISTENTRY *e, Datum k,
Relation r, Page pg,
OffsetNumber o, int b, bool l, bool isNull);
static void gistDeCompressAtt(GISTSTATE *giststate, Relation r,
IndexTuple tuple, Page p, OffsetNumber o,
GISTENTRY *attdata, bool *isnull);
static void gistpenalty(GISTSTATE *giststate, int attno,
GISTENTRY *key1, bool isNull1,
GISTENTRY *key2, bool isNull2,
float *penalty);
#undef GISTDEBUG
#ifdef GISTDEBUG
static void gist_dumptree(Relation r, int level, BlockNumber blk, OffsetNumber coff);
#endif
/*
* Create and return a temporary memory context for use by GiST. We
* _always_ invoke user-provided methods in a temporary memory
* context, so that memory leaks in those functions cannot cause
* problems. Also, we use some additional temporary contexts in the
* GiST code itself, to avoid the need to do some awkward manual
* memory management.
*/
MemoryContext
createTempGistContext(void)
{
return AllocSetContextCreate(CurrentMemoryContext,
"GiST temporary context",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
}
/*
* Routine to build an index. Basically calls insert over and over.
*
* XXX: it would be nice to implement some sort of bulk-loading
* algorithm, but it is not clear how to do that.
*/
Datum
gistbuild(PG_FUNCTION_ARGS)
{
Relation heap = (Relation) PG_GETARG_POINTER(0);
Relation index = (Relation) PG_GETARG_POINTER(1);
IndexInfo *indexInfo = (IndexInfo *) PG_GETARG_POINTER(2);
double reltuples;
GISTBuildState buildstate;
Buffer buffer;
/*
* We expect to be called exactly once for any index relation. If
* that's not the case, big trouble's what we have.
*/
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
/* no locking is needed */
initGISTstate(&buildstate.giststate, index);
/* initialize the root page */
buffer = ReadBuffer(index, P_NEW);
GISTInitBuffer(buffer, F_LEAF);
WriteBuffer(buffer);
/* build the index */
buildstate.numindexattrs = indexInfo->ii_NumIndexAttrs;
buildstate.indtuples = 0;
/*
* create a temporary memory context that is reset once for each
* tuple inserted into the index
*/
buildstate.tmpCxt = createTempGistContext();
/* do the heap scan */
reltuples = IndexBuildHeapScan(heap, index, indexInfo,
gistbuildCallback, (void *) &buildstate);
/* okay, all heap tuples are indexed */
MemoryContextDelete(buildstate.tmpCxt);
/* since we just counted the # of tuples, may as well update stats */
IndexCloseAndUpdateStats(heap, reltuples, index, buildstate.indtuples);
freeGISTstate(&buildstate.giststate);
#ifdef GISTDEBUG
gist_dumptree(index, 0, GIST_ROOT_BLKNO, 0);
#endif
PG_RETURN_VOID();
}
/*
* Per-tuple callback from IndexBuildHeapScan
*/
static void
gistbuildCallback(Relation index,
HeapTuple htup,
Datum *values,
bool *isnull,
bool tupleIsAlive,
void *state)
{
GISTBuildState *buildstate = (GISTBuildState *) state;
IndexTuple itup;
GISTENTRY tmpcentry;
int i;
MemoryContext oldCxt;
/* GiST cannot index tuples with leading NULLs */
if (isnull[0])
return;
oldCxt = MemoryContextSwitchTo(buildstate->tmpCxt);
/* immediately compress keys to normalize */
for (i = 0; i < buildstate->numindexattrs; i++)
{
if (isnull[i])
values[i] = (Datum) 0;
else
{
gistcentryinit(&buildstate->giststate, i, &tmpcentry, values[i],
NULL, NULL, (OffsetNumber) 0,
-1 /* size is currently bogus */, TRUE, FALSE);
values[i] = tmpcentry.key;
}
}
/* form an index tuple and point it at the heap tuple */
itup = index_form_tuple(buildstate->giststate.tupdesc, values, isnull);
itup->t_tid = htup->t_self;
/*
* Since we already have the index relation locked, we call
* gistdoinsert directly. Normal access method calls dispatch through
* gistinsert, 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.
*/
gistdoinsert(index, itup, &buildstate->giststate);
buildstate->indtuples += 1;
MemoryContextSwitchTo(oldCxt);
MemoryContextReset(buildstate->tmpCxt);
}
/*
* gistinsert -- wrapper for GiST tuple insertion.
*
* This is the public interface routine for tuple insertion in GiSTs.
* It doesn't do any work; just locks the relation and passes the buck.
*/
Datum
gistinsert(PG_FUNCTION_ARGS)
{
Relation r = (Relation) PG_GETARG_POINTER(0);
Datum *values = (Datum *) PG_GETARG_POINTER(1);
bool *isnull = (bool *) PG_GETARG_POINTER(2);
ItemPointer ht_ctid = (ItemPointer) PG_GETARG_POINTER(3);
#ifdef NOT_USED
Relation heapRel = (Relation) PG_GETARG_POINTER(4);
bool checkUnique = PG_GETARG_BOOL(5);
#endif
IndexTuple itup;
GISTSTATE giststate;
GISTENTRY tmpentry;
int i;
MemoryContext oldCxt;
MemoryContext insertCxt;
/*
* Since GIST is not marked "amconcurrent" in pg_am, caller should
* have acquired exclusive lock on index relation. We need no locking
* here.
*/
/* GiST cannot index tuples with leading NULLs */
if (isnull[0])
PG_RETURN_BOOL(false);
insertCxt = createTempGistContext();
oldCxt = MemoryContextSwitchTo(insertCxt);
initGISTstate(&giststate, r);
/* immediately compress keys to normalize */
for (i = 0; i < r->rd_att->natts; i++)
{
if (isnull[i])
values[i] = (Datum) 0;
else
{
gistcentryinit(&giststate, i, &tmpentry, values[i],
NULL, NULL, (OffsetNumber) 0,
-1 /* size is currently bogus */, TRUE, FALSE);
values[i] = tmpentry.key;
}
}
itup = index_form_tuple(giststate.tupdesc, values, isnull);
itup->t_tid = *ht_ctid;
gistdoinsert(r, itup, &giststate);
/* cleanup */
freeGISTstate(&giststate);
MemoryContextSwitchTo(oldCxt);
MemoryContextDelete(insertCxt);
PG_RETURN_BOOL(true);
}
#ifdef GIST_PAGEADDITEM
/*
* Take a compressed entry, and install it on a page. Since we now know
* where the entry will live, we decompress it and recompress it using
* that knowledge (some compression routines may want to fish around
* on the page, for example, or do something special for leaf nodes.)
*/
static OffsetNumber
gistPageAddItem(GISTSTATE *giststate,
Relation r,
Page page,
Item item,
Size size,
OffsetNumber offsetNumber,
ItemIdFlags flags,
GISTENTRY *dentry,
IndexTuple *newtup)
{
GISTENTRY tmpcentry;
IndexTuple itup = (IndexTuple) item;
OffsetNumber retval;
Datum datum;
bool IsNull;
/*
* recompress the item given that we now know the exact page and
* offset for insertion
*/
datum = index_getattr(itup, 1, r->rd_att, &IsNull);
gistdentryinit(giststate, 0, dentry, datum,
(Relation) 0, (Page) 0,
(OffsetNumber) InvalidOffsetNumber,
ATTSIZE(datum, r, 1, IsNull),
FALSE, IsNull);
gistcentryinit(giststate, 0, &tmpcentry, dentry->key, r, page,
offsetNumber, dentry->bytes, FALSE);
*newtup = gist_tuple_replacekey(r, tmpcentry, itup);
retval = PageAddItem(page, (Item) *newtup, IndexTupleSize(*newtup),
offsetNumber, flags);
if (retval == InvalidOffsetNumber)
elog(ERROR, "failed to add index item to \"%s\"",
RelationGetRelationName(r));
return retval;
}
#endif
/*
* Workhouse routine for doing insertion into a GiST index. Note that
* this routine assumes it is invoked in a short-lived memory context,
* so it does not bother releasing palloc'd allocations.
*/
static void
gistdoinsert(Relation r, IndexTuple itup, GISTSTATE *giststate)
{
IndexTuple *instup;
int ret,
len = 1;
instup = (IndexTuple *) palloc(sizeof(IndexTuple));
instup[0] = (IndexTuple) palloc(IndexTupleSize(itup));
memcpy(instup[0], itup, IndexTupleSize(itup));
ret = gistlayerinsert(r, GIST_ROOT_BLKNO, &instup, &len, giststate);
if (ret & SPLITED)
gistnewroot(r, instup, len);
}
static int
gistlayerinsert(Relation r, BlockNumber blkno,
IndexTuple **itup, /* in - out, has compressed entry */
int *len, /* in - out */
GISTSTATE *giststate)
{
Buffer buffer;
Page page;
int ret;
GISTPageOpaque opaque;
buffer = ReadBuffer(r, blkno);
page = (Page) BufferGetPage(buffer);
opaque = (GISTPageOpaque) PageGetSpecialPointer(page);
if (!(opaque->flags & F_LEAF))
{
/*
* This is an internal page, so continue to walk down the
* tree. We find the child node that has the minimum insertion
* penalty and recursively invoke ourselves to modify that
* node. Once the recursive call returns, we may need to
* adjust the parent node for two reasons: the child node
* split, or the key in this node needs to be adjusted for the
* newly inserted key below us.
*/
ItemId iid;
BlockNumber nblkno;
ItemPointerData oldtid;
IndexTuple oldtup;
OffsetNumber child;
child = gistchoose(r, page, *(*itup), giststate);
iid = PageGetItemId(page, child);
oldtup = (IndexTuple) PageGetItem(page, iid);
nblkno = ItemPointerGetBlockNumber(&(oldtup->t_tid));
/*
* After this call: 1. if child page was splited, then itup
* contains keys for each page 2. if child page wasn't splited,
* then itup contains additional for adjustment of current key
*/
ret = gistlayerinsert(r, nblkno, itup, len, giststate);
/* nothing inserted in child */
if (!(ret & INSERTED))
{
ReleaseBuffer(buffer);
return 0x00;
}
/* child did not split */
if (!(ret & SPLITED))
{
IndexTuple newtup = gistgetadjusted(r, oldtup, (*itup)[0], giststate);
if (!newtup)
{
/* not need to update key */
ReleaseBuffer(buffer);
return 0x00;
}
(*itup)[0] = newtup;
}
/*
* This node's key has been modified, either because a child
* split occurred or because we needed to adjust our key for
* an insert in a child node. Therefore, remove the old
* version of this node's key.
*/
ItemPointerSet(&oldtid, blkno, child);
gistdelete(r, &oldtid);
/*
* if child was splitted, new key for child will be inserted in
* the end list of child, so we must say to any scans that page is
* changed beginning from 'child' offset
*/
if (ret & SPLITED)
gistadjscans(r, GISTOP_SPLIT, blkno, child);
}
ret = INSERTED;
if (gistnospace(page, (*itup), *len))
{
/* no space for insertion */
IndexTuple *itvec,
*newitup;
int tlen,
oldlen;
ret |= SPLITED;
itvec = gistreadbuffer(buffer, &tlen);
itvec = gistjoinvector(itvec, &tlen, (*itup), *len);
oldlen = *len;
newitup = gistSplit(r, buffer, itvec, &tlen, giststate);
ReleaseBuffer(buffer);
*itup = newitup;
*len = tlen; /* now tlen >= 2 */
}
else
{
/* enough space */
OffsetNumber off,
l;
off = (PageIsEmpty(page)) ?
FirstOffsetNumber
:
OffsetNumberNext(PageGetMaxOffsetNumber(page));
l = gistwritebuffer(r, page, *itup, *len, off);
WriteBuffer(buffer);
if (*len > 1)
{ /* previous insert ret & SPLITED != 0 */
/*
* child was splited, so we must form union for insertion in
* parent
*/
IndexTuple newtup = gistunion(r, (*itup), *len, giststate);
ItemPointerSet(&(newtup->t_tid), blkno, 1);
(*itup)[0] = newtup;
*len = 1;
}
}
return ret;
}
/*
* Write itup vector to page, has no control of free space
*/
static OffsetNumber
gistwritebuffer(Relation r, Page page, IndexTuple *itup,
int len, OffsetNumber off)
{
OffsetNumber l = InvalidOffsetNumber;
int i;
for (i = 0; i < len; i++)
{
#ifdef GIST_PAGEADDITEM
GISTENTRY tmpdentry;
IndexTuple newtup;
bool IsNull;
l = gistPageAddItem(giststate, r, page,
(Item) itup[i], IndexTupleSize(itup[i]),
off, LP_USED, &tmpdentry, &newtup);
off = OffsetNumberNext(off);
#else
l = PageAddItem(page, (Item) itup[i], IndexTupleSize(itup[i]),
off, LP_USED);
if (l == InvalidOffsetNumber)
elog(ERROR, "failed to add index item to \"%s\"",
RelationGetRelationName(r));
#endif
}
return l;
}
/*
* Check space for itup vector on page
*/
static bool
gistnospace(Page page, IndexTuple *itvec, int len)
{
unsigned int size = 0;
int i;
for (i = 0; i < len; i++)
size += IndexTupleSize(itvec[i]) + sizeof(ItemIdData);
return (PageGetFreeSpace(page) < size);
}
/*
* Read buffer into itup vector
*/
static IndexTuple *
gistreadbuffer(Buffer buffer, int *len /* out */ )
{
OffsetNumber i,
maxoff;
IndexTuple *itvec;
Page p = (Page) BufferGetPage(buffer);
maxoff = PageGetMaxOffsetNumber(p);
*len = maxoff;
itvec = palloc(sizeof(IndexTuple) * maxoff);
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
itvec[i - 1] = (IndexTuple) PageGetItem(p, PageGetItemId(p, i));
return itvec;
}
/*
* join two vectors into one
*/
static IndexTuple *
gistjoinvector(IndexTuple *itvec, int *len, IndexTuple *additvec, int addlen)
{
itvec = (IndexTuple *) repalloc((void *) itvec, sizeof(IndexTuple) * ((*len) + addlen));
memmove(&itvec[*len], additvec, sizeof(IndexTuple) * addlen);
*len += addlen;
return itvec;
}
/*
* Return an IndexTuple containing the result of applying the "union"
* method to the specified IndexTuple vector.
*/
static IndexTuple
gistunion(Relation r, IndexTuple *itvec, int len, GISTSTATE *giststate)
{
Datum attr[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
GistEntryVector *evec;
int i;
GISTENTRY centry[INDEX_MAX_KEYS];
evec = (GistEntryVector *) palloc(((len == 1) ? 2 : len) * sizeof(GISTENTRY) + GEVHDRSZ);
for (i = 0; i < r->rd_att->natts; i++)
{
Datum datum;
int j;
int real_len;
real_len = 0;
for (j = 0; j < len; j++)
{
bool IsNull;
datum = index_getattr(itvec[j], i + 1, giststate->tupdesc, &IsNull);
if (IsNull)
continue;
gistdentryinit(giststate, i,
&(evec->vector[real_len]),
datum,
NULL, NULL, (OffsetNumber) 0,
ATTSIZE(datum, giststate->tupdesc, i + 1, IsNull),
FALSE, IsNull);
real_len++;
}
/* If this tuple vector was all NULLs, the union is NULL */
if (real_len == 0)
{
attr[i] = (Datum) 0;
isnull[i] = TRUE;
}
else
{
int datumsize;
if (real_len == 1)
{
evec->n = 2;
gistentryinit(evec->vector[1],
evec->vector[0].key, r, NULL,
(OffsetNumber) 0, evec->vector[0].bytes, FALSE);
}
else
evec->n = real_len;
/* Compress the result of the union and store in attr array */
datum = FunctionCall2(&giststate->unionFn[i],
PointerGetDatum(evec),
PointerGetDatum(&datumsize));
gistcentryinit(giststate, i, ¢ry[i], datum,
NULL, NULL, (OffsetNumber) 0,
datumsize, FALSE, FALSE);
isnull[i] = FALSE;
attr[i] = centry[i].key;
}
}
return index_form_tuple(giststate->tupdesc, attr, isnull);
}
/*
* Forms union of oldtup and addtup, if union == oldtup then return NULL
*/
static IndexTuple
gistgetadjusted(Relation r, IndexTuple oldtup, IndexTuple addtup, GISTSTATE *giststate)
{
GistEntryVector *evec;
bool neednew = false;
bool isnull[INDEX_MAX_KEYS];
Datum attr[INDEX_MAX_KEYS];
GISTENTRY centry[INDEX_MAX_KEYS],
oldatt[INDEX_MAX_KEYS],
addatt[INDEX_MAX_KEYS],
*ev0p,
*ev1p;
bool oldisnull[INDEX_MAX_KEYS],
addisnull[INDEX_MAX_KEYS];
IndexTuple newtup = NULL;
int i;
evec = palloc(2 * sizeof(GISTENTRY) + GEVHDRSZ);
evec->n = 2;
ev0p = &(evec->vector[0]);
ev1p = &(evec->vector[1]);
gistDeCompressAtt(giststate, r, oldtup, NULL,
(OffsetNumber) 0, oldatt, oldisnull);
gistDeCompressAtt(giststate, r, addtup, NULL,
(OffsetNumber) 0, addatt, addisnull);
for (i = 0; i < r->rd_att->natts; i++)
{
if (oldisnull[i] && addisnull[i])
{
attr[i] = (Datum) 0;
isnull[i] = TRUE;
}
else
{
Datum datum;
int datumsize;
FILLEV(oldisnull[i], oldatt[i].key, oldatt[i].bytes,
addisnull[i], addatt[i].key, addatt[i].bytes);
datum = FunctionCall2(&giststate->unionFn[i],
PointerGetDatum(evec),
PointerGetDatum(&datumsize));
if (oldisnull[i] || addisnull[i])
{
if (oldisnull[i])
neednew = true;
}
else
{
bool result;
FunctionCall3(&giststate->equalFn[i],
ev0p->key,
datum,
PointerGetDatum(&result));
if (!result)
neednew = true;
}
gistcentryinit(giststate, i, ¢ry[i], datum,
NULL, NULL, (OffsetNumber) 0,
datumsize, FALSE, FALSE);
attr[i] = centry[i].key;
isnull[i] = FALSE;
}
}
if (neednew)
{
/* need to update key */
newtup = index_form_tuple(giststate->tupdesc, attr, isnull);
newtup->t_tid = oldtup->t_tid;
}
return newtup;
}
static void
gistunionsubkey(Relation r, GISTSTATE *giststate, IndexTuple *itvec, GIST_SPLITVEC *spl)
{
int lr;
for (lr = 0; lr < 2; lr++)
{
OffsetNumber *entries;
int i;
Datum *attr;
int len,
*attrsize;
bool *isnull;
GistEntryVector *evec;
if (lr)
{
attrsize = spl->spl_lattrsize;
attr = spl->spl_lattr;
len = spl->spl_nleft;
entries = spl->spl_left;
isnull = spl->spl_lisnull;
}
else
{
attrsize = spl->spl_rattrsize;
attr = spl->spl_rattr;
len = spl->spl_nright;
entries = spl->spl_right;
isnull = spl->spl_risnull;
}
evec = palloc(((len == 1) ? 2 : len) * sizeof(GISTENTRY) + GEVHDRSZ);
for (i = 1; i < r->rd_att->natts; i++)
{
int j;
Datum datum;
int datumsize;
int real_len;
real_len = 0;
for (j = 0; j < len; j++)
{
bool IsNull;
if (spl->spl_idgrp[entries[j]])
continue;
datum = index_getattr(itvec[entries[j] - 1], i + 1,
giststate->tupdesc, &IsNull);
if (IsNull)
continue;
gistdentryinit(giststate, i,
&(evec->vector[real_len]),
datum,
NULL, NULL, (OffsetNumber) 0,
ATTSIZE(datum, giststate->tupdesc, i + 1, IsNull),
FALSE, IsNull);
real_len++;
}
if (real_len == 0)
{
datum = (Datum) 0;
datumsize = 0;
isnull[i] = true;
}
else
{
/*
* evec->vector[0].bytes may be not defined, so form union
* with itself
*/
if (real_len == 1)
{
evec->n = 2;
memcpy(&(evec->vector[1]), &(evec->vector[0]),
sizeof(GISTENTRY));
}
else
evec->n = real_len;
datum = FunctionCall2(&giststate->unionFn[i],
PointerGetDatum(evec),
PointerGetDatum(&datumsize));
isnull[i] = false;
}
attr[i] = datum;
attrsize[i] = datumsize;
}
}
}
/*
* find group in vector with equal value
*/
static int
gistfindgroup(GISTSTATE *giststate, GISTENTRY *valvec, GIST_SPLITVEC *spl)
{
int i;
int curid = 1;
/*
* first key is always not null (see gistinsert), so we may not check
* for nulls
*/
for (i = 0; i < spl->spl_nleft; i++)
{
int j;
int len;
bool result;
if (spl->spl_idgrp[spl->spl_left[i]])
continue;
len = 0;
/* find all equal value in right part */
for (j = 0; j < spl->spl_nright; j++)
{
if (spl->spl_idgrp[spl->spl_right[j]])
continue;
FunctionCall3(&giststate->equalFn[0],
valvec[spl->spl_left[i]].key,
valvec[spl->spl_right[j]].key,
PointerGetDatum(&result));
if (result)
{
spl->spl_idgrp[spl->spl_right[j]] = curid;
len++;
}
}
/* find all other equal value in left part */
if (len)
{
/* add current val to list of equal values */
spl->spl_idgrp[spl->spl_left[i]] = curid;
/* searching .. */
for (j = i + 1; j < spl->spl_nleft; j++)
{
if (spl->spl_idgrp[spl->spl_left[j]])
continue;
FunctionCall3(&giststate->equalFn[0],
valvec[spl->spl_left[i]].key,
valvec[spl->spl_left[j]].key,
PointerGetDatum(&result));
if (result)
{
spl->spl_idgrp[spl->spl_left[j]] = curid;
len++;
}
}
spl->spl_ngrp[curid] = len + 1;
curid++;
}
}
return curid;
}
/*
* Insert equivalent tuples to left or right page with minimum
* penalty
*/
static void
gistadjsubkey(Relation r,
IndexTuple *itup, /* contains compressed entry */
int *len,
GIST_SPLITVEC *v,
GISTSTATE *giststate)
{
int curlen;
OffsetNumber *curwpos;
GISTENTRY entry,
identry[INDEX_MAX_KEYS],
*ev0p,
*ev1p;
float lpenalty,
rpenalty;
GistEntryVector *evec;
int datumsize;
bool isnull[INDEX_MAX_KEYS];
int i,
j;
/* clear vectors */
curlen = v->spl_nleft;
curwpos = v->spl_left;
for (i = 0; i < v->spl_nleft; i++)
{
if (v->spl_idgrp[v->spl_left[i]] == 0)
{
*curwpos = v->spl_left[i];
curwpos++;
}
else
curlen--;
}
v->spl_nleft = curlen;
curlen = v->spl_nright;
curwpos = v->spl_right;
for (i = 0; i < v->spl_nright; i++)
{
if (v->spl_idgrp[v->spl_right[i]] == 0)
{
*curwpos = v->spl_right[i];
curwpos++;
}
else
curlen--;
}
v->spl_nright = curlen;
evec = palloc(2 * sizeof(GISTENTRY) + GEVHDRSZ);
evec->n = 2;
ev0p = &(evec->vector[0]);
ev1p = &(evec->vector[1]);
/* add equivalent tuple */
for (i = 0; i < *len; i++)
{
Datum datum;
if (v->spl_idgrp[i + 1] == 0) /* already inserted */
continue;
gistDeCompressAtt(giststate, r, itup[i], NULL, (OffsetNumber) 0,
identry, isnull);
v->spl_ngrp[v->spl_idgrp[i + 1]]--;
if (v->spl_ngrp[v->spl_idgrp[i + 1]] == 0 &&
(v->spl_grpflag[v->spl_idgrp[i + 1]] & BOTH_ADDED) != BOTH_ADDED)
{
/* force last in group */
rpenalty = 1.0;
lpenalty = (v->spl_grpflag[v->spl_idgrp[i + 1]] & LEFT_ADDED) ? 2.0 : 0.0;
}
else
{
/* where? */
for (j = 1; j < r->rd_att->natts; j++)
{
gistentryinit(entry, v->spl_lattr[j], r, NULL,
(OffsetNumber) 0, v->spl_lattrsize[j], FALSE);
gistpenalty(giststate, j, &entry, v->spl_lisnull[j],
&identry[j], isnull[j], &lpenalty);
gistentryinit(entry, v->spl_rattr[j], r, NULL,
(OffsetNumber) 0, v->spl_rattrsize[j], FALSE);
gistpenalty(giststate, j, &entry, v->spl_risnull[j],
&identry[j], isnull[j], &rpenalty);
if (lpenalty != rpenalty)
break;
}
}
/*
* add
* XXX: refactor this to avoid duplicating code
*/
if (lpenalty < rpenalty)
{
v->spl_grpflag[v->spl_idgrp[i + 1]] |= LEFT_ADDED;
v->spl_left[v->spl_nleft] = i + 1;
v->spl_nleft++;
for (j = 1; j < r->rd_att->natts; j++)
{
if (isnull[j] && v->spl_lisnull[j])
{
v->spl_lattr[j] = (Datum) 0;
v->spl_lattrsize[j] = 0;
}
else
{
FILLEV(v->spl_lisnull[j], v->spl_lattr[j], v->spl_lattrsize[j],
isnull[j], identry[j].key, identry[j].bytes);
datum = FunctionCall2(&giststate->unionFn[j],
PointerGetDatum(evec),
PointerGetDatum(&datumsize));
v->spl_lattr[j] = datum;
v->spl_lattrsize[j] = datumsize;
v->spl_lisnull[j] = false;
}
}
}
else
{
v->spl_grpflag[v->spl_idgrp[i + 1]] |= RIGHT_ADDED;
v->spl_right[v->spl_nright] = i + 1;
v->spl_nright++;
for (j = 1; j < r->rd_att->natts; j++)
{
if (isnull[j] && v->spl_risnull[j])
{
v->spl_rattr[j] = (Datum) 0;
v->spl_rattrsize[j] = 0;
}
else
{
FILLEV(v->spl_risnull[j], v->spl_rattr[j], v->spl_rattrsize[j],
isnull[j], identry[j].key, identry[j].bytes);
datum = FunctionCall2(&giststate->unionFn[j],
PointerGetDatum(evec),
PointerGetDatum(&datumsize));
v->spl_rattr[j] = datum;
v->spl_rattrsize[j] = datumsize;
v->spl_risnull[j] = false;
}
}
}
}
}
/*
* gistSplit -- split a page in the tree.
*/
static IndexTuple *
gistSplit(Relation r,
Buffer buffer,
IndexTuple *itup, /* contains compressed entry */
int *len,
GISTSTATE *giststate)
{
Page p;
Buffer leftbuf,
rightbuf;
Page left,
right;
IndexTuple *lvectup,
*rvectup,
*newtup;
BlockNumber lbknum,
rbknum;
GISTPageOpaque opaque;
GIST_SPLITVEC v;
GistEntryVector *entryvec;
int i,
nlen;
p = (Page) BufferGetPage(buffer);
opaque = (GISTPageOpaque) 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) == GIST_ROOT_BLKNO)
{
leftbuf = ReadBuffer(r, P_NEW);
GISTInitBuffer(leftbuf, opaque->flags);
lbknum = BufferGetBlockNumber(leftbuf);
left = (Page) BufferGetPage(leftbuf);
}
else
{
leftbuf = buffer;
IncrBufferRefCount(buffer);
lbknum = BufferGetBlockNumber(buffer);
left = (Page) PageGetTempPage(p, sizeof(GISTPageOpaqueData));
}
rightbuf = ReadBuffer(r, P_NEW);
GISTInitBuffer(rightbuf, opaque->flags);
rbknum = BufferGetBlockNumber(rightbuf);
right = (Page) BufferGetPage(rightbuf);
/* generate the item array */
entryvec = palloc(GEVHDRSZ + (*len + 1) * sizeof(GISTENTRY));
entryvec->n = *len + 1;
for (i = 1; i <= *len; i++)
{
Datum datum;
bool IsNull;
datum = index_getattr(itup[i - 1], 1, giststate->tupdesc, &IsNull);
gistdentryinit(giststate, 0, &(entryvec->vector[i]),
datum, r, p, i,
ATTSIZE(datum, giststate->tupdesc, 1, IsNull),
FALSE, IsNull);
}
/*
* now let the user-defined picksplit function set up the split
* vector; in entryvec have no null value!!
*/
FunctionCall2(&giststate->picksplitFn[0],
PointerGetDatum(entryvec),
PointerGetDatum(&v));
/* compatibility with old code */
if (v.spl_left[v.spl_nleft - 1] == InvalidOffsetNumber)
v.spl_left[v.spl_nleft - 1] = (OffsetNumber) *len;
if (v.spl_right[v.spl_nright - 1] == InvalidOffsetNumber)
v.spl_right[v.spl_nright - 1] = (OffsetNumber) *len;
v.spl_lattr[0] = v.spl_ldatum;
v.spl_rattr[0] = v.spl_rdatum;
v.spl_lisnull[0] = false;
v.spl_risnull[0] = false;
/*
* if index is multikey, then we must to try get smaller bounding box
* for subkey(s)
*/
if (r->rd_att->natts > 1)
{
int MaxGrpId;
v.spl_idgrp = (int *) palloc0(sizeof(int) * (*len + 1));
v.spl_grpflag = (char *) palloc0(sizeof(char) * (*len + 1));
v.spl_ngrp = (int *) palloc(sizeof(int) * (*len + 1));
MaxGrpId = gistfindgroup(giststate, entryvec->vector, &v);
/* form union of sub keys for each page (l,p) */
gistunionsubkey(r, giststate, itup, &v);
/*
* if possible, we insert equivalent tuples with control by
* penalty for a subkey(s)
*/
if (MaxGrpId > 1)
gistadjsubkey(r, itup, len, &v, giststate);
}
/* form left and right vector */
lvectup = (IndexTuple *) palloc(sizeof(IndexTuple) * v.spl_nleft);
rvectup = (IndexTuple *) palloc(sizeof(IndexTuple) * v.spl_nright);
for (i = 0; i < v.spl_nleft; i++)
lvectup[i] = itup[v.spl_left[i] - 1];
for (i = 0; i < v.spl_nright; i++)
rvectup[i] = itup[v.spl_right[i] - 1];
/* write on disk (may need another split) */
if (gistnospace(right, rvectup, v.spl_nright))
{
nlen = v.spl_nright;
newtup = gistSplit(r, rightbuf, rvectup, &nlen, giststate);
ReleaseBuffer(rightbuf);
}
else
{
OffsetNumber l;
l = gistwritebuffer(r, right, rvectup, v.spl_nright, FirstOffsetNumber);
WriteBuffer(rightbuf);
nlen = 1;
newtup = (IndexTuple *) palloc(sizeof(IndexTuple) * 1);
newtup[0] = gistFormTuple(giststate, r, v.spl_rattr, v.spl_rattrsize, v.spl_risnull);
ItemPointerSet(&(newtup[0]->t_tid), rbknum, 1);
}
if (gistnospace(left, lvectup, v.spl_nleft))
{
int llen = v.spl_nleft;
IndexTuple *lntup;
lntup = gistSplit(r, leftbuf, lvectup, &llen, giststate);
ReleaseBuffer(leftbuf);
newtup = gistjoinvector(newtup, &nlen, lntup, llen);
}
else
{
OffsetNumber l;
l = gistwritebuffer(r, left, lvectup, v.spl_nleft, FirstOffsetNumber);
if (BufferGetBlockNumber(buffer) != GIST_ROOT_BLKNO)
PageRestoreTempPage(left, p);
WriteBuffer(leftbuf);
nlen += 1;
newtup = (IndexTuple *) repalloc(newtup, sizeof(IndexTuple) * nlen);
newtup[nlen - 1] = gistFormTuple(giststate, r, v.spl_lattr, v.spl_lattrsize, v.spl_lisnull);
ItemPointerSet(&(newtup[nlen - 1]->t_tid), lbknum, 1);
}
*len = nlen;
return newtup;
}
static void
gistnewroot(Relation r, IndexTuple *itup, int len)
{
Buffer b;
Page p;
b = ReadBuffer(r, GIST_ROOT_BLKNO);
GISTInitBuffer(b, 0);
p = BufferGetPage(b);
gistwritebuffer(r, p, itup, len, FirstOffsetNumber);
WriteBuffer(b);
}
static void
GISTInitBuffer(Buffer b, uint32 f)
{
GISTPageOpaque opaque;
Page page;
Size pageSize;
pageSize = BufferGetPageSize(b);
page = BufferGetPage(b);
PageInit(page, pageSize, sizeof(GISTPageOpaqueData));
opaque = (GISTPageOpaque) PageGetSpecialPointer(page);
opaque->flags = f;
}
/*
* find entry with lowest penalty
*/
static OffsetNumber
gistchoose(Relation r, Page p, IndexTuple it, /* it has compressed entry */
GISTSTATE *giststate)
{
OffsetNumber maxoff;
OffsetNumber i;
OffsetNumber which;
float sum_grow,
which_grow[INDEX_MAX_KEYS];
GISTENTRY entry,
identry[INDEX_MAX_KEYS];
bool isnull[INDEX_MAX_KEYS];
maxoff = PageGetMaxOffsetNumber(p);
*which_grow = -1.0;
which = -1;
sum_grow = 1;
gistDeCompressAtt(giststate, r,
it, NULL, (OffsetNumber) 0,
identry, isnull);
for (i = FirstOffsetNumber; i <= maxoff && sum_grow; i = OffsetNumberNext(i))
{
int j;
IndexTuple itup = (IndexTuple) PageGetItem(p, PageGetItemId(p, i));
sum_grow = 0;
for (j = 0; j < r->rd_att->natts; j++)
{
Datum datum;
float usize;
bool IsNull;
datum = index_getattr(itup, j + 1, giststate->tupdesc, &IsNull);
gistdentryinit(giststate, j, &entry, datum, r, p, i,
ATTSIZE(datum, giststate->tupdesc, j + 1, IsNull),
FALSE, IsNull);
gistpenalty(giststate, j, &entry, IsNull,
&identry[j], isnull[j], &usize);
if (which_grow[j] < 0 || usize < which_grow[j])
{
which = i;
which_grow[j] = usize;
if (j < r->rd_att->natts - 1 && i == FirstOffsetNumber)
which_grow[j + 1] = -1;
sum_grow += which_grow[j];
}
else if (which_grow[j] == usize)
sum_grow += usize;
else
{
sum_grow = 1;
break;
}
}
}
return which;
}
/*
* Retail deletion of a single tuple.
*
* NB: this is no longer called externally, but is still needed by
* gistlayerinsert(). That dependency will have to be fixed if GIST
* is ever going to allow concurrent insertions.
*/
static void
gistdelete(Relation r, ItemPointer tid)
{
BlockNumber blkno;
OffsetNumber offnum;
Buffer buf;
Page page;
/*
* Since GIST is not marked "amconcurrent" in pg_am, caller should
* have acquired exclusive lock on index relation. We need no locking
* here.
*/
blkno = ItemPointerGetBlockNumber(tid);
offnum = ItemPointerGetOffsetNumber(tid);
/* adjust any scans that will be affected by this deletion */
/* NB: this works only for scans in *this* backend! */
gistadjscans(r, GISTOP_DEL, blkno, offnum);
/* delete the index tuple */
buf = ReadBuffer(r, blkno);
page = BufferGetPage(buf);
PageIndexTupleDelete(page, offnum);
WriteBuffer(buf);
}
/*
* Bulk deletion of all index entries pointing to a set of heap tuples.
* The set of target tuples is specified via a callback routine that tells
* whether any given heap tuple (identified by ItemPointer) is being deleted.
*
* Result: a palloc'd struct containing statistical info for VACUUM displays.
*/
Datum
gistbulkdelete(PG_FUNCTION_ARGS)
{
Relation rel = (Relation) PG_GETARG_POINTER(0);
IndexBulkDeleteCallback callback = (IndexBulkDeleteCallback) PG_GETARG_POINTER(1);
void *callback_state = (void *) PG_GETARG_POINTER(2);
IndexBulkDeleteResult *result;
BlockNumber num_pages;
double tuples_removed;
double num_index_tuples;
IndexScanDesc iscan;
tuples_removed = 0;
num_index_tuples = 0;
/*
* Since GIST is not marked "amconcurrent" in pg_am, caller should
* have acquired exclusive lock on index relation. We need no locking
* here.
*/
/*
* XXX generic implementation --- should be improved!
*/
/* walk through the entire index */
iscan = index_beginscan(NULL, rel, SnapshotAny, 0, NULL);
/* including killed tuples */
iscan->ignore_killed_tuples = false;
while (index_getnext_indexitem(iscan, ForwardScanDirection))
{
vacuum_delay_point();
if (callback(&iscan->xs_ctup.t_self, callback_state))
{
ItemPointerData indextup = iscan->currentItemData;
BlockNumber blkno;
OffsetNumber offnum;
Buffer buf;
Page page;
blkno = ItemPointerGetBlockNumber(&indextup);
offnum = ItemPointerGetOffsetNumber(&indextup);
/* adjust any scans that will be affected by this deletion */
gistadjscans(rel, GISTOP_DEL, blkno, offnum);
/* delete the index tuple */
buf = ReadBuffer(rel, blkno);
page = BufferGetPage(buf);
PageIndexTupleDelete(page, offnum);
WriteBuffer(buf);
tuples_removed += 1;
}
else
num_index_tuples += 1;
}
index_endscan(iscan);
/* return statistics */
num_pages = RelationGetNumberOfBlocks(rel);
result = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
result->num_pages = num_pages;
result->num_index_tuples = num_index_tuples;
result->tuples_removed = tuples_removed;
PG_RETURN_POINTER(result);
}
void
initGISTstate(GISTSTATE *giststate, Relation index)
{
int i;
if (index->rd_att->natts > INDEX_MAX_KEYS)
elog(ERROR, "numberOfAttributes %d > %d",
index->rd_att->natts, INDEX_MAX_KEYS);
giststate->tupdesc = index->rd_att;
for (i = 0; i < index->rd_att->natts; i++)
{
fmgr_info_copy(&(giststate->consistentFn[i]),
index_getprocinfo(index, i + 1, GIST_CONSISTENT_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->unionFn[i]),
index_getprocinfo(index, i + 1, GIST_UNION_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->compressFn[i]),
index_getprocinfo(index, i + 1, GIST_COMPRESS_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->decompressFn[i]),
index_getprocinfo(index, i + 1, GIST_DECOMPRESS_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->penaltyFn[i]),
index_getprocinfo(index, i + 1, GIST_PENALTY_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->picksplitFn[i]),
index_getprocinfo(index, i + 1, GIST_PICKSPLIT_PROC),
CurrentMemoryContext);
fmgr_info_copy(&(giststate->equalFn[i]),
index_getprocinfo(index, i + 1, GIST_EQUAL_PROC),
CurrentMemoryContext);
}
}
void
freeGISTstate(GISTSTATE *giststate)
{
/* no work */
}
#ifdef GIST_PAGEADDITEM
/*
* Given an IndexTuple to be inserted on a page, this routine replaces
* the key with another key, which may involve generating a new IndexTuple
* if the sizes don't match or if the null status changes.
*
* XXX this only works for a single-column index tuple!
*/
static IndexTuple
gist_tuple_replacekey(Relation r, GISTENTRY entry, IndexTuple t)
{
bool IsNull;
Datum datum = index_getattr(t, 1, r->rd_att, &IsNull);
/*
* If new entry fits in index tuple, copy it in. To avoid worrying
* about null-value bitmask, pass it off to the general
* index_form_tuple routine if either the previous or new value is
* NULL.
*/
if (!IsNull && DatumGetPointer(entry.key) != NULL &&
(Size) entry.bytes <= ATTSIZE(datum, r, 1, IsNull))
{
memcpy(DatumGetPointer(datum),
DatumGetPointer(entry.key),
entry.bytes);
/* clear out old size */
t->t_info &= ~INDEX_SIZE_MASK;
/* or in new size */
t->t_info |= MAXALIGN(entry.bytes + sizeof(IndexTupleData));
return t;
}
else
{
/* generate a new index tuple for the compressed entry */
TupleDesc tupDesc = r->rd_att;
IndexTuple newtup;
bool isnull;
isnull = (DatumGetPointer(entry.key) == NULL);
newtup = index_form_tuple(tupDesc, &(entry.key), &isnull);
newtup->t_tid = t->t_tid;
return newtup;
}
}
#endif
/*
* initialize a GiST entry with a decompressed version of key
*/
void
gistdentryinit(GISTSTATE *giststate, int nkey, GISTENTRY *e,
Datum k, Relation r, Page pg, OffsetNumber o,
int b, bool l, bool isNull)
{
if (b && !isNull)
{
GISTENTRY *dep;
gistentryinit(*e, k, r, pg, o, b, l);
dep = (GISTENTRY *)
DatumGetPointer(FunctionCall1(&giststate->decompressFn[nkey],
PointerGetDatum(e)));
/* decompressFn may just return the given pointer */
if (dep != e)
gistentryinit(*e, dep->key, dep->rel, dep->page, dep->offset,
dep->bytes, dep->leafkey);
}
else
gistentryinit(*e, (Datum) 0, r, pg, o, 0, l);
}
/*
* initialize a GiST entry with a compressed version of key
*/
static void
gistcentryinit(GISTSTATE *giststate, int nkey,
GISTENTRY *e, Datum k, Relation r,
Page pg, OffsetNumber o, int b, bool l, bool isNull)
{
if (!isNull)
{
GISTENTRY *cep;
gistentryinit(*e, k, r, pg, o, b, l);
cep = (GISTENTRY *)
DatumGetPointer(FunctionCall1(&giststate->compressFn[nkey],
PointerGetDatum(e)));
/* compressFn may just return the given pointer */
if (cep != e)
gistentryinit(*e, cep->key, cep->rel, cep->page, cep->offset,
cep->bytes, cep->leafkey);
}
else
gistentryinit(*e, (Datum) 0, r, pg, o, 0, l);
}
static IndexTuple
gistFormTuple(GISTSTATE *giststate, Relation r,
Datum attdata[], int datumsize[], bool isnull[])
{
GISTENTRY centry[INDEX_MAX_KEYS];
Datum compatt[INDEX_MAX_KEYS];
int i;
for (i = 0; i < r->rd_att->natts; i++)
{
if (isnull[i])
compatt[i] = (Datum) 0;
else
{
gistcentryinit(giststate, i, ¢ry[i], attdata[i],
NULL, NULL, (OffsetNumber) 0,
datumsize[i], FALSE, FALSE);
compatt[i] = centry[i].key;
}
}
return index_form_tuple(giststate->tupdesc, compatt, isnull);
}
static void
gistDeCompressAtt(GISTSTATE *giststate, Relation r, IndexTuple tuple, Page p,
OffsetNumber o, GISTENTRY *attdata, bool *isnull)
{
int i;
for (i = 0; i < r->rd_att->natts; i++)
{
Datum datum = index_getattr(tuple, i + 1, giststate->tupdesc, &isnull[i]);
gistdentryinit(giststate, i, &attdata[i],
datum, r, p, o,
ATTSIZE(datum, giststate->tupdesc, i + 1, isnull[i]),
FALSE, isnull[i]);
}
}
static void
gistpenalty(GISTSTATE *giststate, int attno,
GISTENTRY *key1, bool isNull1,
GISTENTRY *key2, bool isNull2, float *penalty)
{
if (giststate->penaltyFn[attno].fn_strict && (isNull1 || isNull2))
*penalty = 0.0;
else
FunctionCall3(&giststate->penaltyFn[attno],
PointerGetDatum(key1),
PointerGetDatum(key2),
PointerGetDatum(penalty));
}
#ifdef GISTDEBUG
static void
gist_dumptree(Relation r, int level, BlockNumber blk, OffsetNumber coff)
{
Buffer buffer;
Page page;
GISTPageOpaque opaque;
IndexTuple which;
ItemId iid;
OffsetNumber i,
maxoff;
BlockNumber cblk;
char *pred;
pred = (char *) palloc(sizeof(char) * level + 1);
MemSet(pred, '\t', level);
pred[level] = '\0';
buffer = ReadBuffer(r, blk);
page = (Page) BufferGetPage(buffer);
opaque = (GISTPageOpaque) PageGetSpecialPointer(page);
maxoff = PageGetMaxOffsetNumber(page);
elog(DEBUG4, "%sPage: %d %s blk: %d maxoff: %d free: %d", pred,
coff, (opaque->flags & F_LEAF) ? "LEAF" : "INTE", (int) blk,
(int) maxoff, PageGetFreeSpace(page));
for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
{
iid = PageGetItemId(page, i);
which = (IndexTuple) PageGetItem(page, iid);
cblk = ItemPointerGetBlockNumber(&(which->t_tid));
#ifdef PRINTTUPLE
elog(DEBUG4, "%s Tuple. blk: %d size: %d", pred, (int) cblk,
IndexTupleSize(which));
#endif
if (!(opaque->flags & F_LEAF))
gist_dumptree(r, level + 1, cblk, i);
}
ReleaseBuffer(buffer);
pfree(pred);
}
#endif /* defined GISTDEBUG */
void
gist_redo(XLogRecPtr lsn, XLogRecord *record)
{
elog(PANIC, "gist_redo: unimplemented");
}
void
gist_desc(char *buf, uint8 xl_info, char *rec)
{
}