int pgno = pSeg->iLeafPgno;
int pgnoSave = 0;
- /* This function does notmwork with detail=none databases. */
+ /* This function does not work with detail=none databases. */
assert( p->pConfig->eDetail!=FTS5_DETAIL_NONE );
if( (pSeg->flags & FTS5_SEGITER_REVERSE)==0 ){
fts5DataRelease(pData);
if( nRem<=0 ){
break;
+ }else if( pSeg->pSeg==0 ){
+ p->rc = FTS5_CORRUPT;
+ return;
}else{
pgno++;
pData = fts5LeafRead(p, FTS5_SEGMENT_ROWID(pSeg->pSeg->iSegid, pgno));
static void fts5DoclistIterNext(Fts5DoclistIter *pIter){
u8 *p = pIter->aPoslist + pIter->nSize + pIter->nPoslist;
- assert( pIter->aPoslist );
+ assert( pIter->aPoslist || (p==0 && pIter->aPoslist==0) );
if( p>=pIter->aEof ){
pIter->aPoslist = 0;
}else{
static void fts5MergeRowidLists(
Fts5Index *p, /* FTS5 backend object */
Fts5Buffer *p1, /* First list to merge */
- Fts5Buffer *p2 /* Second list to merge */
+ int nBuf, /* Number of entries in apBuf[] */
+ Fts5Buffer *aBuf /* Array of other lists to merge into p1 */
){
int i1 = 0;
int i2 = 0;
i64 iRowid1 = 0;
i64 iRowid2 = 0;
i64 iOut = 0;
+ Fts5Buffer *p2 = &aBuf[0];
Fts5Buffer out;
memset(&out, 0, sizeof(out));
+ assert( nBuf==1 );
sqlite3Fts5BufferSize(&p->rc, &out, p1->n + p2->n);
if( p->rc ) return;
fts5BufferFree(&out);
}
+typedef struct PrefixMerger PrefixMerger;
+struct PrefixMerger {
+ Fts5DoclistIter iter; /* Doclist iterator */
+ i64 iPos; /* For iterating through a position list */
+ int iOff;
+ u8 *aPos;
+ PrefixMerger *pNext; /* Next in docid/poslist order */
+};
+
+static void fts5PrefixMergerInsertByRowid(
+ PrefixMerger **ppHead,
+ PrefixMerger *p
+){
+ if( p->iter.aPoslist ){
+ PrefixMerger **pp = ppHead;
+ while( *pp && p->iter.iRowid>(*pp)->iter.iRowid ){
+ pp = &(*pp)->pNext;
+ }
+ p->pNext = *pp;
+ *pp = p;
+ }
+}
+
+static void fts5PrefixMergerInsertByPosition(
+ PrefixMerger **ppHead,
+ PrefixMerger *p
+){
+ if( p->iPos>=0 ){
+ PrefixMerger **pp = ppHead;
+ while( *pp && p->iPos>(*pp)->iPos ){
+ pp = &(*pp)->pNext;
+ }
+ p->pNext = *pp;
+ *pp = p;
+ }
+}
+
+
/*
-** Buffers p1 and p2 contain doclists. This function merges the content
-** of the two doclists together and sets buffer p1 to the result before
-** returning.
-**
-** If an error occurs, an error code is left in p->rc. If an error has
-** already occurred, this function is a no-op.
+** Array aBuf[] contains nBuf doclists. These are all merged in with the
+** doclist in buffer p1.
*/
static void fts5MergePrefixLists(
Fts5Index *p, /* FTS5 backend object */
Fts5Buffer *p1, /* First list to merge */
- Fts5Buffer *p2 /* Second list to merge */
+ int nBuf, /* Number of buffers in array aBuf[] */
+ Fts5Buffer *aBuf /* Other lists to merge in */
){
- if( p2->n ){
- i64 iLastRowid = 0;
- Fts5DoclistIter i1;
- Fts5DoclistIter i2;
- Fts5Buffer out = {0, 0, 0};
- Fts5Buffer tmp = {0, 0, 0};
-
- /* The maximum size of the output is equal to the sum of the two
- ** input sizes + 1 varint (9 bytes). The extra varint is because if the
- ** first rowid in one input is a large negative number, and the first in
- ** the other a non-negative number, the delta for the non-negative
- ** number will be larger on disk than the literal integer value
- ** was.
- **
- ** Or, if the input position-lists are corrupt, then the output might
- ** include up to 2 extra 10-byte positions created by interpreting -1
- ** (the value PoslistNext64() uses for EOF) as a position and appending
- ** it to the output. This can happen at most once for each input
- ** position-list, hence two 10 byte paddings. */
- if( sqlite3Fts5BufferSize(&p->rc, &out, p1->n + p2->n + 9+10+10) ) return;
- fts5DoclistIterInit(p1, &i1);
- fts5DoclistIterInit(p2, &i2);
-
- while( 1 ){
- if( i1.iRowid<i2.iRowid ){
- /* Copy entry from i1 */
- fts5MergeAppendDocid(&out, iLastRowid, i1.iRowid);
- fts5BufferSafeAppendBlob(&out, i1.aPoslist, i1.nPoslist+i1.nSize);
- fts5DoclistIterNext(&i1);
- if( i1.aPoslist==0 ) break;
- assert( out.n<=((i1.aPoslist-p1->p) + (i2.aPoslist-p2->p)+9+10+10) );
- }
- else if( i2.iRowid!=i1.iRowid ){
- /* Copy entry from i2 */
- fts5MergeAppendDocid(&out, iLastRowid, i2.iRowid);
- fts5BufferSafeAppendBlob(&out, i2.aPoslist, i2.nPoslist+i2.nSize);
- fts5DoclistIterNext(&i2);
- if( i2.aPoslist==0 ) break;
- assert( out.n<=((i1.aPoslist-p1->p) + (i2.aPoslist-p2->p)+9+10+10) );
+#define fts5PrefixMergerNextPosition(p) \
+ sqlite3Fts5PoslistNext64((p)->aPos,(p)->iter.nPoslist,&(p)->iOff,&(p)->iPos);
+#define FTS5_MERGE_NLIST 16
+ PrefixMerger aMerger[FTS5_MERGE_NLIST];
+ PrefixMerger *pHead = 0;
+ int i;
+ int nOut = 0;
+ Fts5Buffer out = {0, 0, 0};
+ Fts5Buffer tmp = {0, 0, 0};
+ i64 iLastRowid = 0;
+
+ /* Initialize a doclist-iterator for each input buffer. Arrange them in
+ ** a linked-list starting at pHead in ascending order of rowid. Avoid
+ ** linking any iterators already at EOF into the linked list at all. */
+ assert( nBuf+1<=sizeof(aMerger)/sizeof(aMerger[0]) );
+ memset(aMerger, 0, sizeof(PrefixMerger)*(nBuf+1));
+ pHead = &aMerger[nBuf];
+ fts5DoclistIterInit(p1, &pHead->iter);
+ for(i=0; i<nBuf; i++){
+ fts5DoclistIterInit(&aBuf[i], &aMerger[i].iter);
+ fts5PrefixMergerInsertByRowid(&pHead, &aMerger[i]);
+ nOut += aBuf[i].n;
+ }
+ if( nOut==0 ) return;
+ nOut += p1->n + 9 + 10*nBuf;
+
+ /* The maximum size of the output is equal to the sum of the
+ ** input sizes + 1 varint (9 bytes). The extra varint is because if the
+ ** first rowid in one input is a large negative number, and the first in
+ ** the other a non-negative number, the delta for the non-negative
+ ** number will be larger on disk than the literal integer value
+ ** was.
+ **
+ ** Or, if the input position-lists are corrupt, then the output might
+ ** include up to (nBuf+1) extra 10-byte positions created by interpreting -1
+ ** (the value PoslistNext64() uses for EOF) as a position and appending
+ ** it to the output. This can happen at most once for each input
+ ** position-list, hence (nBuf+1) 10 byte paddings. */
+ if( sqlite3Fts5BufferSize(&p->rc, &out, nOut) ) return;
+
+ while( pHead ){
+ fts5MergeAppendDocid(&out, iLastRowid, pHead->iter.iRowid);
+
+ if( pHead->pNext && iLastRowid==pHead->pNext->iter.iRowid ){
+ /* Merge data from two or more poslists */
+ i64 iPrev = 0;
+ int nTmp = FTS5_DATA_ZERO_PADDING;
+ int nMerge = 0;
+ PrefixMerger *pSave = pHead;
+ PrefixMerger *pThis = 0;
+ int nTail = 0;
+
+ pHead = 0;
+ while( pSave && pSave->iter.iRowid==iLastRowid ){
+ PrefixMerger *pNext = pSave->pNext;
+ pSave->iOff = 0;
+ pSave->iPos = 0;
+ pSave->aPos = &pSave->iter.aPoslist[pSave->iter.nSize];
+ fts5PrefixMergerNextPosition(pSave);
+ nTmp += pSave->iter.nPoslist + 10;
+ nMerge++;
+ fts5PrefixMergerInsertByPosition(&pHead, pSave);
+ pSave = pNext;
}
- else{
- /* Merge the two position lists. */
- i64 iPos1 = 0;
- i64 iPos2 = 0;
- int iOff1 = 0;
- int iOff2 = 0;
- u8 *a1 = &i1.aPoslist[i1.nSize];
- u8 *a2 = &i2.aPoslist[i2.nSize];
- int nCopy;
- u8 *aCopy;
-
- i64 iPrev = 0;
- Fts5PoslistWriter writer;
- memset(&writer, 0, sizeof(writer));
-
- /* See the earlier comment in this function for an explanation of why
- ** corrupt input position lists might cause the output to consume
- ** at most 20 bytes of unexpected space. */
- fts5MergeAppendDocid(&out, iLastRowid, i2.iRowid);
- fts5BufferZero(&tmp);
- sqlite3Fts5BufferSize(&p->rc, &tmp,
- i1.nPoslist + i2.nPoslist + 10 + 10 + FTS5_DATA_ZERO_PADDING
- );
- if( p->rc ) break;
- sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1, &iPos1);
- sqlite3Fts5PoslistNext64(a2, i2.nPoslist, &iOff2, &iPos2);
- assert_nc( iPos1>=0 && iPos2>=0 );
+ if( pHead==0 || pHead->pNext==0 ){
+ p->rc = FTS5_CORRUPT;
+ break;
+ }
- if( iPos1<iPos2 ){
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos1);
- sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1, &iPos1);
- }else{
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos2);
- sqlite3Fts5PoslistNext64(a2, i2.nPoslist, &iOff2, &iPos2);
- }
- if( iPos1>=0 && iPos2>=0 ){
- while( 1 ){
- if( iPos1<iPos2 ){
- if( iPos1!=iPrev ){
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos1);
- }
- sqlite3Fts5PoslistNext64(a1, i1.nPoslist, &iOff1, &iPos1);
- if( iPos1<0 ) break;
- }else{
- assert_nc( iPos2!=iPrev );
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos2);
- sqlite3Fts5PoslistNext64(a2, i2.nPoslist, &iOff2, &iPos2);
- if( iPos2<0 ) break;
- }
- }
+ /* See the earlier comment in this function for an explanation of why
+ ** corrupt input position lists might cause the output to consume
+ ** at most nMerge*10 bytes of unexpected space. */
+ if( sqlite3Fts5BufferSize(&p->rc, &tmp, nTmp+nMerge*10) ){
+ break;
+ }
+ fts5BufferZero(&tmp);
+
+ pThis = pHead;
+ pHead = pThis->pNext;
+ sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, pThis->iPos);
+ fts5PrefixMergerNextPosition(pThis);
+ fts5PrefixMergerInsertByPosition(&pHead, pThis);
+
+ while( pHead->pNext ){
+ pThis = pHead;
+ if( pThis->iPos!=iPrev ){
+ sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, pThis->iPos);
}
+ fts5PrefixMergerNextPosition(pThis);
+ pHead = pThis->pNext;
+ fts5PrefixMergerInsertByPosition(&pHead, pThis);
+ }
- if( iPos1>=0 ){
- if( iPos1!=iPrev ){
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos1);
- }
- aCopy = &a1[iOff1];
- nCopy = i1.nPoslist - iOff1;
- }else{
- assert_nc( iPos2>=0 && iPos2!=iPrev );
- sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, iPos2);
- aCopy = &a2[iOff2];
- nCopy = i2.nPoslist - iOff2;
- }
- if( nCopy>0 ){
- fts5BufferSafeAppendBlob(&tmp, aCopy, nCopy);
- }
+ if( pHead->iPos!=iPrev ){
+ sqlite3Fts5PoslistSafeAppend(&tmp, &iPrev, pHead->iPos);
+ }
+ nTail = pHead->iter.nPoslist - pHead->iOff;
- /* WRITEPOSLISTSIZE */
- assert_nc( tmp.n<=i1.nPoslist+i2.nPoslist );
- assert( tmp.n<=i1.nPoslist+i2.nPoslist+10+10 );
- if( tmp.n>i1.nPoslist+i2.nPoslist ){
- if( p->rc==SQLITE_OK ) p->rc = FTS5_CORRUPT;
- break;
+ /* WRITEPOSLISTSIZE */
+ assert( tmp.n+nTail<=nTmp );
+ if( tmp.n+nTail>nTmp-FTS5_DATA_ZERO_PADDING ){
+ if( p->rc==SQLITE_OK ) p->rc = FTS5_CORRUPT;
+ break;
+ }
+ fts5BufferSafeAppendVarint(&out, (tmp.n+nTail) * 2);
+ fts5BufferSafeAppendBlob(&out, tmp.p, tmp.n);
+ if( nTail>0 ){
+ fts5BufferSafeAppendBlob(&out, &pHead->aPos[pHead->iOff], nTail);
+ }
+
+ pHead = pSave;
+ for(i=0; i<nBuf+1; i++){
+ PrefixMerger *pThis = &aMerger[i];
+ if( pThis->iter.aPoslist && pThis->iter.iRowid==iLastRowid ){
+ fts5DoclistIterNext(&pThis->iter);
+ fts5PrefixMergerInsertByRowid(&pHead, pThis);
}
- fts5BufferSafeAppendVarint(&out, tmp.n * 2);
- fts5BufferSafeAppendBlob(&out, tmp.p, tmp.n);
- fts5DoclistIterNext(&i1);
- fts5DoclistIterNext(&i2);
- assert_nc( out.n<=(p1->n+p2->n+9) );
- if( i1.aPoslist==0 || i2.aPoslist==0 ) break;
- assert( out.n<=((i1.aPoslist-p1->p) + (i2.aPoslist-p2->p)+9+10+10) );
}
- }
- if( i1.aPoslist ){
- fts5MergeAppendDocid(&out, iLastRowid, i1.iRowid);
- fts5BufferSafeAppendBlob(&out, i1.aPoslist, i1.aEof - i1.aPoslist);
- }
- else if( i2.aPoslist ){
- fts5MergeAppendDocid(&out, iLastRowid, i2.iRowid);
- fts5BufferSafeAppendBlob(&out, i2.aPoslist, i2.aEof - i2.aPoslist);
+ }else{
+ /* Copy poslist from pHead to output */
+ PrefixMerger *pThis = pHead;
+ Fts5DoclistIter *pI = &pThis->iter;
+ fts5BufferSafeAppendBlob(&out, pI->aPoslist, pI->nPoslist+pI->nSize);
+ fts5DoclistIterNext(pI);
+ pHead = pThis->pNext;
+ fts5PrefixMergerInsertByRowid(&pHead, pThis);
}
- assert_nc( out.n<=(p1->n+p2->n+9) );
-
- fts5BufferFree(p1);
- fts5BufferFree(&tmp);
- memset(&out.p[out.n], 0, FTS5_DATA_ZERO_PADDING);
- *p1 = out;
}
+
+ fts5BufferFree(p1);
+ fts5BufferFree(&tmp);
+ memset(&out.p[out.n], 0, FTS5_DATA_ZERO_PADDING);
+ *p1 = out;
}
static void fts5SetupPrefixIter(
){
Fts5Structure *pStruct;
Fts5Buffer *aBuf;
- const int nBuf = 32;
+ int nBuf = 32;
+ int nMerge = 1;
- void (*xMerge)(Fts5Index*, Fts5Buffer*, Fts5Buffer*);
+ void (*xMerge)(Fts5Index*, Fts5Buffer*, int, Fts5Buffer*);
void (*xAppend)(Fts5Index*, i64, Fts5Iter*, Fts5Buffer*);
if( p->pConfig->eDetail==FTS5_DETAIL_NONE ){
xMerge = fts5MergeRowidLists;
xAppend = fts5AppendRowid;
}else{
+ nMerge = FTS5_MERGE_NLIST-1;
+ nBuf = nMerge*8; /* Sufficient to merge (16^8)==(2^32) lists */
xMerge = fts5MergePrefixLists;
xAppend = fts5AppendPoslist;
}
if( p1->base.iRowid<=iLastRowid && doclist.n>0 ){
for(i=0; p->rc==SQLITE_OK && doclist.n; i++){
- assert( i<nBuf );
- if( aBuf[i].n==0 ){
- fts5BufferSwap(&doclist, &aBuf[i]);
- fts5BufferZero(&doclist);
- }else{
- xMerge(p, &doclist, &aBuf[i]);
- fts5BufferZero(&aBuf[i]);
+ int i1 = i*nMerge;
+ int iStore;
+ assert( i1+nMerge<=nBuf );
+ for(iStore=i1; iStore<i1+nMerge; iStore++){
+ if( aBuf[iStore].n==0 ){
+ fts5BufferSwap(&doclist, &aBuf[iStore]);
+ fts5BufferZero(&doclist);
+ break;
+ }
+ }
+ if( iStore==i1+nMerge ){
+ xMerge(p, &doclist, nMerge, &aBuf[i1]);
+ for(iStore=i1; iStore<i1+nMerge; iStore++){
+ fts5BufferZero(&aBuf[iStore]);
+ }
}
}
iLastRowid = 0;
iLastRowid = p1->base.iRowid;
}
- for(i=0; i<nBuf; i++){
+ assert( (nBuf%nMerge)==0 );
+ for(i=0; i<nBuf; i+=nMerge){
+ int iFree;
if( p->rc==SQLITE_OK ){
- xMerge(p, &doclist, &aBuf[i]);
+ xMerge(p, &doclist, nMerge, &aBuf[i]);
+ }
+ for(iFree=i; iFree<i+nMerge; iFree++){
+ fts5BufferFree(&aBuf[iFree]);
}
- fts5BufferFree(&aBuf[i]);
}
fts5MultiIterFree(p1);
projects / thirdparty / sqlite.git / commitdiff
