/*
* Return an IndexTuple containing the result of applying the "union"
* method to the specified IndexTuple vector.
*/
IndexTuple
gistunion(Relation r, IndexTuple *itvec, int len, GISTSTATE *giststate)
{
memset(isnullS, TRUE, sizeof(bool) * giststate->tupdesc->natts);
if (!gistMakeUnionItVec(giststate, itvec, len, 0, attrS, isnullS))
return gist_form_invalid_tuple(InvalidBlockNumber);
return gistFormTuple(giststate, r, attrS, isnullS, false);
}
/*
* Forms union of oldtup and addtup, if union == oldtup then return NULL
*/
IndexTuple
gistgetadjusted(Relation r, IndexTuple oldtup, IndexTuple addtup, GISTSTATE *giststate)
{
bool neednew = FALSE;
GISTENTRY oldentries[INDEX_MAX_KEYS],
addentries[INDEX_MAX_KEYS];
bool oldisnull[INDEX_MAX_KEYS],
addisnull[INDEX_MAX_KEYS];
IndexTuple newtup = NULL;
int i;
if (GistTupleIsInvalid(oldtup) || GistTupleIsInvalid(addtup))
return gist_form_invalid_tuple(ItemPointerGetBlockNumber(&(oldtup->t_tid)));
gistDeCompressAtt(giststate, r, oldtup, NULL,
(OffsetNumber) 0, oldentries, oldisnull);
gistDeCompressAtt(giststate, r, addtup, NULL,
(OffsetNumber) 0, addentries, addisnull);
for (i = 0; i < r->rd_att->natts; i++)
{
gistMakeUnionKey(giststate, i,
oldentries + i, oldisnull[i],
addentries + i, addisnull[i],
attrS + i, isnullS + i);
if (neednew)
/* we already need new key, so we can skip check */
continue;
if (isnullS[i])
/* union of key may be NULL if and only if both keys are NULL */
continue;
if (!addisnull[i])
{
if (oldisnull[i] || gistKeyIsEQ(giststate, i, oldentries[i].key, attrS[i]) == false)
neednew = true;
}
}
if (neednew)
{
/* need to update key */
newtup = gistFormTuple(giststate, r, attrS, isnullS, false);
newtup->t_tid = oldtup->t_tid;
}
return newtup;
}
/*
* gistSplit -- split a page in the tree and fill struct
* used for XLOG and real writes buffers. Function is recursive, ie
* it will split page until keys will fit in every page.
*/
SplitedPageLayout *
gistSplit(Relation r,
Page page,
IndexTuple *itup, /* contains compressed entry */
int len,
GISTSTATE *giststate)
{
IndexTuple *lvectup,
*rvectup;
GistSplitVector v;
GistEntryVector *entryvec;
int i;
SplitedPageLayout *res = NULL;
/* generate the item array */
entryvec = palloc(GEVHDRSZ + (len + 1) * sizeof(GISTENTRY));
entryvec->n = len + 1;
memset(v.spl_lisnull, TRUE, sizeof(bool) * giststate->tupdesc->natts);
memset(v.spl_risnull, TRUE, sizeof(bool) * giststate->tupdesc->natts);
gistSplitByKey(r, page, itup, len, giststate,
&v, entryvec, 0);
/* form left and right vector */
lvectup = (IndexTuple *) palloc(sizeof(IndexTuple) * (len + 1));
rvectup = (IndexTuple *) palloc(sizeof(IndexTuple) * (len + 1));
for (i = 0; i < v.splitVector.spl_nleft; i++)
lvectup[i] = itup[v.splitVector.spl_left[i] - 1];
for (i = 0; i < v.splitVector.spl_nright; i++)
rvectup[i] = itup[v.splitVector.spl_right[i] - 1];
/* finalize splitting (may need another split) */
if (!gistfitpage(rvectup, v.splitVector.spl_nright))
{
res = gistSplit(r, page, rvectup, v.splitVector.spl_nright, giststate);
}
else
{
ROTATEDIST(res);
res->block.num = v.splitVector.spl_nright;
res->list = gistfillitupvec(rvectup, v.splitVector.spl_nright, &(res->lenlist));
res->itup = (v.spl_rightvalid) ? gistFormTuple(giststate, r, v.spl_rattr, v.spl_risnull, false)
: gist_form_invalid_tuple(GIST_ROOT_BLKNO);
}
if (!gistfitpage(lvectup, v.splitVector.spl_nleft))
{
SplitedPageLayout *resptr,
*subres;
resptr = subres = gistSplit(r, page, lvectup, v.splitVector.spl_nleft, giststate);
/* install on list's tail */
while (resptr->next)
resptr = resptr->next;
resptr->next = res;
res = subres;
}
else
{
ROTATEDIST(res);
res->block.num = v.splitVector.spl_nleft;
res->list = gistfillitupvec(lvectup, v.splitVector.spl_nleft, &(res->lenlist));
res->itup = (v.spl_leftvalid) ? gistFormTuple(giststate, r, v.spl_lattr, v.spl_lisnull, false)
: gist_form_invalid_tuple(GIST_ROOT_BLKNO);
}
return res;
}
