ginentrypage.c File Reference

#include "postgres.h"
#include "access/gin_private.h"
#include "access/ginxlog.h"
#include "access/xloginsert.h"
#include "utils/rel.h"

Include dependency graph for ginentrypage.c:

Go to the source code of this file.

Functions
static void	entrySplitPage (GinBtree btree, Buffer origbuf, GinBtreeStack *stack, GinBtreeEntryInsertData *insertData, BlockNumber updateblkno, Page *newlpage, Page *newrpage)
IndexTuple	GinFormTuple (GinState *ginstate, OffsetNumber attnum, Datum key, GinNullCategory category, Pointer data, Size dataSize, int nipd, bool errorTooBig)
ItemPointer	ginReadTuple (GinState *ginstate, OffsetNumber attnum, IndexTuple itup, int *nitems)
static IndexTuple	GinFormInteriorTuple (IndexTuple itup, Page page, BlockNumber childblk)
static IndexTuple	getRightMostTuple (Page page)
static bool	entryIsMoveRight (GinBtree btree, Page page)
static BlockNumber	entryLocateEntry (GinBtree btree, GinBtreeStack *stack)
static bool	entryLocateLeafEntry (GinBtree btree, GinBtreeStack *stack)
static OffsetNumber	entryFindChildPtr (GinBtree btree, Page page, BlockNumber blkno, OffsetNumber storedOff)
static BlockNumber	entryGetLeftMostPage (GinBtree btree, Page page)
static bool	entryIsEnoughSpace (GinBtree btree, Buffer buf, OffsetNumber off, GinBtreeEntryInsertData *insertData)
static void	entryPreparePage (GinBtree btree, Page page, OffsetNumber off, GinBtreeEntryInsertData *insertData, BlockNumber updateblkno)
static GinPlaceToPageRC	entryBeginPlaceToPage (GinBtree btree, Buffer buf, GinBtreeStack *stack, void *insertPayload, BlockNumber updateblkno, void **ptp_workspace, Page *newlpage, Page *newrpage)
static void	entryExecPlaceToPage (GinBtree btree, Buffer buf, GinBtreeStack *stack, void *insertPayload, BlockNumber updateblkno, void *ptp_workspace)
static void *	entryPrepareDownlink (GinBtree btree, Buffer lbuf)
void	ginEntryFillRoot (GinBtree btree, Page root, BlockNumber lblkno, Page lpage, BlockNumber rblkno, Page rpage)
void	ginPrepareEntryScan (GinBtree btree, OffsetNumber attnum, Datum key, GinNullCategory category, GinState *ginstate)

Function Documentation

entryBeginPlaceToPage()

static GinPlaceToPageRC entryBeginPlaceToPage ( GinBtree  btree, Buffer  buf, GinBtreeStack *  stack, void *  insertPayload, BlockNumber  updateblkno, void **  ptp_workspace, Page *  newlpage, Page *  newrpage  )

static

Definition at line 527 of file ginentrypage.c.

{
    GinBtreeEntryInsertData *insertData = insertPayload;
    OffsetNumber off = stack->off;
 
    /* If it doesn't fit, deal with split case */
    if (!entryIsEnoughSpace(btree, buf, off, insertData))
    {
        entrySplitPage(btree, buf, stack, insertData, updateblkno,
                       newlpage, newrpage);
        return GPTP_SPLIT;
    }
 
    /* Else, we're ready to proceed with insertion */
    return GPTP_INSERT;
}

References buf, entryIsEnoughSpace(), entrySplitPage(), GPTP_INSERT, GPTP_SPLIT, and GinBtreeStack::off.

Referenced by ginPrepareEntryScan().

entryExecPlaceToPage()

static void entryExecPlaceToPage ( GinBtree  btree, Buffer  buf, GinBtreeStack *  stack, void *  insertPayload, BlockNumber  updateblkno, void *  ptp_workspace  )

static

Definition at line 554 of file ginentrypage.c.

{
    GinBtreeEntryInsertData *insertData = insertPayload;
    Page        page = BufferGetPage(buf);
    OffsetNumber off = stack->off;
    OffsetNumber placed;
 
    entryPreparePage(btree, page, off, insertData, updateblkno);
 
    placed = PageAddItem(page,
                         (Item) insertData->entry,
                         IndexTupleSize(insertData->entry),
                         off, false, false);
    if (placed != off)
        elog(ERROR, "failed to add item to index page in \"%s\"",
             RelationGetRelationName(btree->index));
 
    MarkBufferDirty(buf);
 
    if (RelationNeedsWAL(btree->index) && !btree->isBuild)
    {
        /*
         * This must be static, because it has to survive until XLogInsert,
         * and we can't palloc here.  Ugly, but the XLogInsert infrastructure
         * isn't reentrant anyway.
         */
        static ginxlogInsertEntry data;
 
        data.isDelete = insertData->isDelete;
        data.offset = off;
 
        XLogRegisterBuffer(0, buf, REGBUF_STANDARD);
        XLogRegisterBufData(0, &data,
                            offsetof(ginxlogInsertEntry, tuple));
        XLogRegisterBufData(0, insertData->entry,
                            IndexTupleSize(insertData->entry));
    }
}

References buf, BufferGetPage(), data, elog, GinBtreeEntryInsertData::entry, entryPreparePage(), ERROR, GinBtreeData::index, IndexTupleSize(), GinBtreeData::isBuild, GinBtreeEntryInsertData::isDelete, MarkBufferDirty(), GinBtreeStack::off, PageAddItem, REGBUF_STANDARD, RelationGetRelationName, RelationNeedsWAL, XLogRegisterBufData(), and XLogRegisterBuffer().

Referenced by ginPrepareEntryScan().

entryFindChildPtr()

static OffsetNumber entryFindChildPtr ( GinBtree  btree, Page  page, BlockNumber  blkno, OffsetNumber  storedOff  )

static

Definition at line 405 of file ginentrypage.c.

{
    OffsetNumber i,
                maxoff = PageGetMaxOffsetNumber(page);
    IndexTuple  itup;
 
    Assert(!GinPageIsLeaf(page));
    Assert(!GinPageIsData(page));
 
    /* if page isn't changed, we returns storedOff */
    if (storedOff >= FirstOffsetNumber && storedOff <= maxoff)
    {
        itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, storedOff));
        if (GinGetDownlink(itup) == blkno)
            return storedOff;
 
        /*
         * we hope, that needed pointer goes to right. It's true if there
         * wasn't a deletion
         */
        for (i = storedOff + 1; i <= maxoff; i++)
        {
            itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, i));
            if (GinGetDownlink(itup) == blkno)
                return i;
        }
        maxoff = storedOff - 1;
    }
 
    /* last chance */
    for (i = FirstOffsetNumber; i <= maxoff; i++)
    {
        itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, i));
        if (GinGetDownlink(itup) == blkno)
            return i;
    }
 
    return InvalidOffsetNumber;
}

References Assert(), FirstOffsetNumber, GinGetDownlink, GinPageIsData, GinPageIsLeaf, i, InvalidOffsetNumber, PageGetItem(), PageGetItemId(), and PageGetMaxOffsetNumber().

Referenced by ginPrepareEntryScan().

entryGetLeftMostPage()

static BlockNumber entryGetLeftMostPage ( GinBtree  btree, Page  page  )

static

Definition at line 446 of file ginentrypage.c.

{
    IndexTuple  itup;
 
    Assert(!GinPageIsLeaf(page));
    Assert(!GinPageIsData(page));
    Assert(PageGetMaxOffsetNumber(page) >= FirstOffsetNumber);
 
    itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, FirstOffsetNumber));
    return GinGetDownlink(itup);
}

References Assert(), FirstOffsetNumber, GinGetDownlink, GinPageIsData, GinPageIsLeaf, PageGetItem(), PageGetItemId(), and PageGetMaxOffsetNumber().

Referenced by ginPrepareEntryScan().

entryIsEnoughSpace()

static bool entryIsEnoughSpace ( GinBtree  btree, Buffer  buf, OffsetNumber  off, GinBtreeEntryInsertData *  insertData  )

static

Definition at line 459 of file ginentrypage.c.

{
    Size        releasedsz = 0;
    Size        addedsz;
    Page        page = BufferGetPage(buf);
 
    Assert(insertData->entry);
    Assert(!GinPageIsData(page));
 
    if (insertData->isDelete)
    {
        IndexTuple  itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, off));
 
        releasedsz = MAXALIGN(IndexTupleSize(itup)) + sizeof(ItemIdData);
    }
 
    addedsz = MAXALIGN(IndexTupleSize(insertData->entry)) + sizeof(ItemIdData);
 
    if (PageGetFreeSpace(page) + releasedsz >= addedsz)
        return true;
 
    return false;
}

References Assert(), buf, BufferGetPage(), GinBtreeEntryInsertData::entry, GinPageIsData, IndexTupleSize(), GinBtreeEntryInsertData::isDelete, MAXALIGN, PageGetFreeSpace(), PageGetItem(), and PageGetItemId().

Referenced by entryBeginPlaceToPage().

entryIsMoveRight()

static bool entryIsMoveRight ( GinBtree  btree, Page  page  )

static

Definition at line 243 of file ginentrypage.c.

{
    IndexTuple  itup;
    OffsetNumber attnum;
    Datum       key;
    GinNullCategory category;
 
    if (GinPageRightMost(page))
        return false;
 
    itup = getRightMostTuple(page);
    attnum = gintuple_get_attrnum(btree->ginstate, itup);
    key = gintuple_get_key(btree->ginstate, itup, &category);
 
    if (ginCompareAttEntries(btree->ginstate,
                             btree->entryAttnum, btree->entryKey, btree->entryCategory,
                             attnum, key, category) > 0)
        return true;
 
    return false;
}

References attnum, GinBtreeData::entryAttnum, GinBtreeData::entryCategory, GinBtreeData::entryKey, getRightMostTuple(), ginCompareAttEntries(), GinPageRightMost, GinBtreeData::ginstate, gintuple_get_attrnum(), gintuple_get_key(), and sort-test::key.

Referenced by ginPrepareEntryScan().

entryLocateEntry()

static BlockNumber entryLocateEntry ( GinBtree  btree, GinBtreeStack *  stack  )

static

Definition at line 270 of file ginentrypage.c.

{
    OffsetNumber low,
                high,
                maxoff;
    IndexTuple  itup = NULL;
    int         result;
    Page        page = BufferGetPage(stack->buffer);
 
    Assert(!GinPageIsLeaf(page));
    Assert(!GinPageIsData(page));
 
    if (btree->fullScan)
    {
        stack->off = FirstOffsetNumber;
        stack->predictNumber *= PageGetMaxOffsetNumber(page);
        return btree->getLeftMostChild(btree, page);
    }
 
    low = FirstOffsetNumber;
    maxoff = high = PageGetMaxOffsetNumber(page);
    Assert(high >= low);
 
    high++;
 
    while (high > low)
    {
        OffsetNumber mid = low + ((high - low) / 2);
 
        if (mid == maxoff && GinPageRightMost(page))
        {
            /* Right infinity */
            result = -1;
        }
        else
        {
            OffsetNumber attnum;
            Datum       key;
            GinNullCategory category;
 
            itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, mid));
            attnum = gintuple_get_attrnum(btree->ginstate, itup);
            key = gintuple_get_key(btree->ginstate, itup, &category);
            result = ginCompareAttEntries(btree->ginstate,
                                          btree->entryAttnum,
                                          btree->entryKey,
                                          btree->entryCategory,
                                          attnum, key, category);
        }
 
        if (result == 0)
        {
            stack->off = mid;
            Assert(GinGetDownlink(itup) != GIN_ROOT_BLKNO);
            return GinGetDownlink(itup);
        }
        else if (result > 0)
            low = mid + 1;
        else
            high = mid;
    }
 
    Assert(high >= FirstOffsetNumber && high <= maxoff);
 
    stack->off = high;
    itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, high));
    Assert(GinGetDownlink(itup) != GIN_ROOT_BLKNO);
    return GinGetDownlink(itup);
}

References Assert(), attnum, GinBtreeStack::buffer, BufferGetPage(), GinBtreeData::entryAttnum, GinBtreeData::entryCategory, GinBtreeData::entryKey, FirstOffsetNumber, GinBtreeData::fullScan, GinBtreeData::getLeftMostChild, GIN_ROOT_BLKNO, ginCompareAttEntries(), GinGetDownlink, GinPageIsData, GinPageIsLeaf, GinPageRightMost, GinBtreeData::ginstate, gintuple_get_attrnum(), gintuple_get_key(), sort-test::key, GinBtreeStack::off, PageGetItem(), PageGetItemId(), PageGetMaxOffsetNumber(), and GinBtreeStack::predictNumber.

Referenced by ginPrepareEntryScan().

entryLocateLeafEntry()

static bool entryLocateLeafEntry ( GinBtree  btree, GinBtreeStack *  stack  )

static

Definition at line 346 of file ginentrypage.c.

{
    Page        page = BufferGetPage(stack->buffer);
    OffsetNumber low,
                high;
 
    Assert(GinPageIsLeaf(page));
    Assert(!GinPageIsData(page));
 
    if (btree->fullScan)
    {
        stack->off = FirstOffsetNumber;
        return true;
    }
 
    low = FirstOffsetNumber;
    high = PageGetMaxOffsetNumber(page);
 
    if (high < low)
    {
        stack->off = FirstOffsetNumber;
        return false;
    }
 
    high++;
 
    while (high > low)
    {
        OffsetNumber mid = low + ((high - low) / 2);
        IndexTuple  itup;
        OffsetNumber attnum;
        Datum       key;
        GinNullCategory category;
        int         result;
 
        itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, mid));
        attnum = gintuple_get_attrnum(btree->ginstate, itup);
        key = gintuple_get_key(btree->ginstate, itup, &category);
        result = ginCompareAttEntries(btree->ginstate,
                                      btree->entryAttnum,
                                      btree->entryKey,
                                      btree->entryCategory,
                                      attnum, key, category);
        if (result == 0)
        {
            stack->off = mid;
            return true;
        }
        else if (result > 0)
            low = mid + 1;
        else
            high = mid;
    }
 
    stack->off = high;
    return false;
}

References Assert(), attnum, GinBtreeStack::buffer, BufferGetPage(), GinBtreeData::entryAttnum, GinBtreeData::entryCategory, GinBtreeData::entryKey, FirstOffsetNumber, GinBtreeData::fullScan, ginCompareAttEntries(), GinPageIsData, GinPageIsLeaf, GinBtreeData::ginstate, gintuple_get_attrnum(), gintuple_get_key(), sort-test::key, GinBtreeStack::off, PageGetItem(), PageGetItemId(), and PageGetMaxOffsetNumber().

Referenced by ginPrepareEntryScan().

entryPrepareDownlink()

static void * entryPrepareDownlink ( GinBtree  btree, Buffer  lbuf  )

static

Definition at line 702 of file ginentrypage.c.

{
    GinBtreeEntryInsertData *insertData;
    Page        lpage = BufferGetPage(lbuf);
    BlockNumber lblkno = BufferGetBlockNumber(lbuf);
    IndexTuple  itup;
 
    itup = getRightMostTuple(lpage);
 
    insertData = palloc(sizeof(GinBtreeEntryInsertData));
    insertData->entry = GinFormInteriorTuple(itup, lpage, lblkno);
    insertData->isDelete = false;
 
    return insertData;
}

References BufferGetBlockNumber(), BufferGetPage(), GinBtreeEntryInsertData::entry, getRightMostTuple(), GinFormInteriorTuple(), GinBtreeEntryInsertData::isDelete, and palloc().

Referenced by ginPrepareEntryScan().

entryPreparePage()

static void entryPreparePage ( GinBtree  btree, Page  page, OffsetNumber  off, GinBtreeEntryInsertData *  insertData, BlockNumber  updateblkno  )

static

Definition at line 490 of file ginentrypage.c.

{
    Assert(insertData->entry);
    Assert(!GinPageIsData(page));
 
    if (insertData->isDelete)
    {
        Assert(GinPageIsLeaf(page));
        PageIndexTupleDelete(page, off);
    }
 
    if (!GinPageIsLeaf(page) && updateblkno != InvalidBlockNumber)
    {
        IndexTuple  itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, off));
 
        GinSetDownlink(itup, updateblkno);
    }
}

References Assert(), GinBtreeEntryInsertData::entry, GinPageIsData, GinPageIsLeaf, GinSetDownlink, InvalidBlockNumber, GinBtreeEntryInsertData::isDelete, PageGetItem(), PageGetItemId(), and PageIndexTupleDelete().

Referenced by entryExecPlaceToPage(), and entrySplitPage().

entrySplitPage()

static void entrySplitPage ( GinBtree  btree, Buffer  origbuf, GinBtreeStack *  stack, GinBtreeEntryInsertData *  insertData, BlockNumber  updateblkno, Page *  newlpage, Page *  newrpage  )

static

Definition at line 602 of file ginentrypage.c.

{
    OffsetNumber off = stack->off;
    OffsetNumber i,
                maxoff,
                separator = InvalidOffsetNumber;
    Size        totalsize = 0;
    Size        lsize = 0,
                size;
    char       *ptr;
    IndexTuple  itup;
    Page        page;
    Page        lpage = PageGetTempPageCopy(BufferGetPage(origbuf));
    Page        rpage = PageGetTempPageCopy(BufferGetPage(origbuf));
    Size        pageSize = PageGetPageSize(lpage);
    PGAlignedBlock tupstore[2]; /* could need 2 pages' worth of tuples */
 
    entryPreparePage(btree, lpage, off, insertData, updateblkno);
 
    /*
     * First, append all the existing tuples and the new tuple we're inserting
     * one after another in a temporary workspace.
     */
    maxoff = PageGetMaxOffsetNumber(lpage);
    ptr = tupstore[0].data;
    for (i = FirstOffsetNumber; i <= maxoff; i++)
    {
        if (i == off)
        {
            size = MAXALIGN(IndexTupleSize(insertData->entry));
            memcpy(ptr, insertData->entry, size);
            ptr += size;
            totalsize += size + sizeof(ItemIdData);
        }
 
        itup = (IndexTuple) PageGetItem(lpage, PageGetItemId(lpage, i));
        size = MAXALIGN(IndexTupleSize(itup));
        memcpy(ptr, itup, size);
        ptr += size;
        totalsize += size + sizeof(ItemIdData);
    }
 
    if (off == maxoff + 1)
    {
        size = MAXALIGN(IndexTupleSize(insertData->entry));
        memcpy(ptr, insertData->entry, size);
        ptr += size;
        totalsize += size + sizeof(ItemIdData);
    }
 
    /*
     * Initialize the left and right pages, and copy all the tuples back to
     * them.
     */
    GinInitPage(rpage, GinPageGetOpaque(lpage)->flags, pageSize);
    GinInitPage(lpage, GinPageGetOpaque(rpage)->flags, pageSize);
 
    ptr = tupstore[0].data;
    maxoff++;
    lsize = 0;
 
    page = lpage;
    for (i = FirstOffsetNumber; i <= maxoff; i++)
    {
        itup = (IndexTuple) ptr;
 
        /*
         * Decide where to split.  We try to equalize the pages' total data
         * size, not number of tuples.
         */
        if (lsize > totalsize / 2)
        {
            if (separator == InvalidOffsetNumber)
                separator = i - 1;
            page = rpage;
        }
        else
        {
            lsize += MAXALIGN(IndexTupleSize(itup)) + sizeof(ItemIdData);
        }
 
        if (PageAddItem(page, (Item) itup, IndexTupleSize(itup), InvalidOffsetNumber, false, false) == InvalidOffsetNumber)
            elog(ERROR, "failed to add item to index page in \"%s\"",
                 RelationGetRelationName(btree->index));
        ptr += MAXALIGN(IndexTupleSize(itup));
    }
 
    /* return temp pages to caller */
    *newlpage = lpage;
    *newrpage = rpage;
}

References BufferGetPage(), PGAlignedBlock::data, elog, GinBtreeEntryInsertData::entry, entryPreparePage(), ERROR, FirstOffsetNumber, GinInitPage(), GinPageGetOpaque, i, GinBtreeData::index, IndexTupleSize(), InvalidOffsetNumber, MAXALIGN, GinBtreeStack::off, PageAddItem, PageGetItem(), PageGetItemId(), PageGetMaxOffsetNumber(), PageGetPageSize(), PageGetTempPageCopy(), and RelationGetRelationName.

Referenced by entryBeginPlaceToPage().

getRightMostTuple()

static IndexTuple getRightMostTuple ( Page  page )

static

Definition at line 235 of file ginentrypage.c.

{
    OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
 
    return (IndexTuple) PageGetItem(page, PageGetItemId(page, maxoff));
}

References PageGetItem(), PageGetItemId(), and PageGetMaxOffsetNumber().

Referenced by entryIsMoveRight(), entryPrepareDownlink(), and ginEntryFillRoot().

ginEntryFillRoot()

void ginEntryFillRoot	(	GinBtree	btree,
		Page	root,
		BlockNumber	lblkno,
		Page	lpage,
		BlockNumber	rblkno,
		Page	rpage
	)

Definition at line 723 of file ginentrypage.c.

{
    IndexTuple  itup;
 
    itup = GinFormInteriorTuple(getRightMostTuple(lpage), lpage, lblkno);
    if (PageAddItem(root, (Item) itup, IndexTupleSize(itup), InvalidOffsetNumber, false, false) == InvalidOffsetNumber)
        elog(ERROR, "failed to add item to index root page");
    pfree(itup);
 
    itup = GinFormInteriorTuple(getRightMostTuple(rpage), rpage, rblkno);
    if (PageAddItem(root, (Item) itup, IndexTupleSize(itup), InvalidOffsetNumber, false, false) == InvalidOffsetNumber)
        elog(ERROR, "failed to add item to index root page");
    pfree(itup);
}

References elog, ERROR, getRightMostTuple(), GinFormInteriorTuple(), IndexTupleSize(), InvalidOffsetNumber, PageAddItem, pfree(), and root.

Referenced by ginPrepareEntryScan().

GinFormInteriorTuple()

static IndexTuple GinFormInteriorTuple ( IndexTuple  itup, Page  page, BlockNumber  childblk  )

static

Definition at line 201 of file ginentrypage.c.

{
    IndexTuple  nitup;
 
    if (GinPageIsLeaf(page) && !GinIsPostingTree(itup))
    {
        /* Tuple contains a posting list, just copy stuff before that */
        uint32      origsize = GinGetPostingOffset(itup);
 
        origsize = MAXALIGN(origsize);
        nitup = (IndexTuple) palloc(origsize);
        memcpy(nitup, itup, origsize);
        /* ... be sure to fix the size header field ... */
        nitup->t_info &= ~INDEX_SIZE_MASK;
        nitup->t_info |= origsize;
    }
    else
    {
        /* Copy the tuple as-is */
        nitup = (IndexTuple) palloc(IndexTupleSize(itup));
        memcpy(nitup, itup, IndexTupleSize(itup));
    }
 
    /* Now insert the correct downlink */
    GinSetDownlink(nitup, childblk);
 
    return nitup;
}

References GinGetPostingOffset, GinIsPostingTree, GinPageIsLeaf, GinSetDownlink, IndexTupleSize(), MAXALIGN, palloc(), and IndexTupleData::t_info.

Referenced by entryPrepareDownlink(), and ginEntryFillRoot().

GinFormTuple()

IndexTuple GinFormTuple	(	GinState *	ginstate,
		OffsetNumber	attnum,
		Datum	key,
		GinNullCategory	category,
		Pointer	data,
		Size	dataSize,
		int	nipd,
		bool	errorTooBig
	)

Definition at line 44 of file ginentrypage.c.

{
    Datum       datums[2];
    bool        isnull[2];
    IndexTuple  itup;
    uint32      newsize;
 
    /* Build the basic tuple: optional column number, plus key datum */
    if (ginstate->oneCol)
    {
        datums[0] = key;
        isnull[0] = (category != GIN_CAT_NORM_KEY);
    }
    else
    {
        datums[0] = UInt16GetDatum(attnum);
        isnull[0] = false;
        datums[1] = key;
        isnull[1] = (category != GIN_CAT_NORM_KEY);
    }
 
    itup = index_form_tuple(ginstate->tupdesc[attnum - 1], datums, isnull);
 
    /*
     * Determine and store offset to the posting list, making sure there is
     * room for the category byte if needed.
     *
     * Note: because index_form_tuple MAXALIGNs the tuple size, there may well
     * be some wasted pad space.  Is it worth recomputing the data length to
     * prevent that?  That would also allow us to Assert that the real data
     * doesn't overlap the GinNullCategory byte, which this code currently
     * takes on faith.
     */
    newsize = IndexTupleSize(itup);
 
    if (IndexTupleHasNulls(itup))
    {
        uint32      minsize;
 
        Assert(category != GIN_CAT_NORM_KEY);
        minsize = GinCategoryOffset(itup, ginstate) + sizeof(GinNullCategory);
        newsize = Max(newsize, minsize);
    }
 
    newsize = SHORTALIGN(newsize);
 
    GinSetPostingOffset(itup, newsize);
    GinSetNPosting(itup, nipd);
 
    /*
     * Add space needed for posting list, if any.  Then check that the tuple
     * won't be too big to store.
     */
    newsize += dataSize;
 
    newsize = MAXALIGN(newsize);
 
    if (newsize > GinMaxItemSize)
    {
        if (errorTooBig)
            ereport(ERROR,
                    (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                     errmsg("index row size %zu exceeds maximum %zu for index \"%s\"",
                            (Size) newsize, (Size) GinMaxItemSize,
                            RelationGetRelationName(ginstate->index))));
        pfree(itup);
        return NULL;
    }
 
    /*
     * Resize tuple if needed
     */
    if (newsize != IndexTupleSize(itup))
    {
        itup = repalloc(itup, newsize);
 
        /*
         * PostgreSQL 9.3 and earlier did not clear this new space, so we
         * might find uninitialized padding when reading tuples from disk.
         */
        memset((char *) itup + IndexTupleSize(itup),
               0, newsize - IndexTupleSize(itup));
        /* set new size in tuple header */
        itup->t_info &= ~INDEX_SIZE_MASK;
        itup->t_info |= newsize;
    }
 
    /*
     * Copy in the posting list, if provided
     */
    if (data)
    {
        char       *ptr = GinGetPosting(itup);
 
        memcpy(ptr, data, dataSize);
    }
 
    /*
     * Insert category byte, if needed
     */
    if (category != GIN_CAT_NORM_KEY)
    {
        Assert(IndexTupleHasNulls(itup));
        GinSetNullCategory(itup, ginstate, category);
    }
    return itup;
}

References Assert(), attnum, data, ereport, errcode(), errmsg(), ERROR, GIN_CAT_NORM_KEY, GinCategoryOffset, GinGetPosting, GinMaxItemSize, GinSetNPosting, GinSetNullCategory, GinSetPostingOffset, GinState::index, index_form_tuple(), IndexTupleHasNulls(), IndexTupleSize(), sort-test::key, Max, MAXALIGN, GinState::oneCol, pfree(), RelationGetRelationName, repalloc(), SHORTALIGN, IndexTupleData::t_info, GinState::tupdesc, and UInt16GetDatum().

Referenced by addItemPointersToLeafTuple(), buildFreshLeafTuple(), ginHeapTupleFastCollect(), and ginVacuumEntryPage().

ginPrepareEntryScan()

void ginPrepareEntryScan	(	GinBtree	btree,
		OffsetNumber	attnum,
		Datum	key,
		GinNullCategory	category,
		GinState *	ginstate
	)

Definition at line 747 of file ginentrypage.c.

{
    memset(btree, 0, sizeof(GinBtreeData));
 
    btree->index = ginstate->index;
    btree->rootBlkno = GIN_ROOT_BLKNO;
    btree->ginstate = ginstate;
 
    btree->findChildPage = entryLocateEntry;
    btree->getLeftMostChild = entryGetLeftMostPage;
    btree->isMoveRight = entryIsMoveRight;
    btree->findItem = entryLocateLeafEntry;
    btree->findChildPtr = entryFindChildPtr;
    btree->beginPlaceToPage = entryBeginPlaceToPage;
    btree->execPlaceToPage = entryExecPlaceToPage;
    btree->fillRoot = ginEntryFillRoot;
    btree->prepareDownlink = entryPrepareDownlink;
 
    btree->isData = false;
    btree->fullScan = false;
    btree->isBuild = false;
 
    btree->entryAttnum = attnum;
    btree->entryKey = key;
    btree->entryCategory = category;
}

References attnum, GinBtreeData::beginPlaceToPage, GinBtreeData::entryAttnum, entryBeginPlaceToPage(), GinBtreeData::entryCategory, entryExecPlaceToPage(), entryFindChildPtr(), entryGetLeftMostPage(), entryIsMoveRight(), GinBtreeData::entryKey, entryLocateEntry(), entryLocateLeafEntry(), entryPrepareDownlink(), GinBtreeData::execPlaceToPage, GinBtreeData::fillRoot, GinBtreeData::findChildPage, GinBtreeData::findChildPtr, GinBtreeData::findItem, GinBtreeData::fullScan, GinBtreeData::getLeftMostChild, GIN_ROOT_BLKNO, ginEntryFillRoot(), GinBtreeData::ginstate, GinState::index, GinBtreeData::index, GinBtreeData::isBuild, GinBtreeData::isData, GinBtreeData::isMoveRight, sort-test::key, GinBtreeData::prepareDownlink, and GinBtreeData::rootBlkno.

Referenced by ginEntryInsert(), and startScanEntry().

ginReadTuple()

ItemPointer ginReadTuple	(	GinState *	ginstate,
		OffsetNumber	attnum,
		IndexTuple	itup,
		int *	nitems
	)

Definition at line 162 of file ginentrypage.c.

{
    Pointer     ptr = GinGetPosting(itup);
    int         nipd = GinGetNPosting(itup);
    ItemPointer ipd;
    int         ndecoded;
 
    if (GinItupIsCompressed(itup))
    {
        if (nipd > 0)
        {
            ipd = ginPostingListDecode((GinPostingList *) ptr, &ndecoded);
            if (nipd != ndecoded)
                elog(ERROR, "number of items mismatch in GIN entry tuple, %d in tuple header, %d decoded",
                     nipd, ndecoded);
        }
        else
        {
            ipd = palloc(0);
        }
    }
    else
    {
        ipd = (ItemPointer) palloc(sizeof(ItemPointerData) * nipd);
        memcpy(ipd, ptr, sizeof(ItemPointerData) * nipd);
    }
    *nitems = nipd;
    return ipd;
}

References elog, ERROR, GinGetNPosting, GinGetPosting, GinItupIsCompressed, ginPostingListDecode(), nitems, and palloc().

Referenced by addItemPointersToLeafTuple(), collectMatchBitmap(), and startScanEntry().