}
#endif
+
+/*
+** Allocate an Fts3MultiSegReader for each token in the expression headed
+** by pExpr.
+**
+** An Fts3SegReader object is a cursor that can seek or scan a range of
+** entries within a single segment b-tree. An Fts3MultiSegReader uses multiple
+** Fts3SegReader objects internally to provide an interface to seek or scan
+** within the union of all segments of a b-tree. Hence the name.
+**
+** If the allocated Fts3MultiSegReader just seeks to a single entry in a
+** segment b-tree (if the term is not a prefix or it is a prefix for which
+** there exists prefix b-tree of the right length) then it may be traversed
+** and merged incrementally. Otherwise, it has to be merged into an in-memory
+** doclist and then traversed.
+*/
+static void fts3EvalAllocateReaders(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pExpr,
+ int *pnToken, /* OUT: Total number of tokens in phrase. */
+ int *pnOr, /* OUT: Total number of OR nodes in expr. */
+ int *pRc
+){
+ if( pExpr && SQLITE_OK==*pRc ){
+ if( pExpr->eType==FTSQUERY_PHRASE ){
+ int i;
+ int nToken = pExpr->pPhrase->nToken;
+ *pnToken += nToken;
+ for(i=0; i<nToken; i++){
+ Fts3PhraseToken *pToken = &pExpr->pPhrase->aToken[i];
+ int rc = sqlite3Fts3TermSegReaderCursor(pCsr,
+ pToken->z, pToken->n, pToken->isPrefix, &pToken->pSegcsr
+ );
+ if( rc!=SQLITE_OK ){
+ *pRc = rc;
+ return;
+ }
+ }
+ }else{
+ *pnOr += (pExpr->eType==FTSQUERY_OR);
+ fts3EvalAllocateReaders(pCsr, pExpr->pLeft, pnToken, pnOr, pRc);
+ fts3EvalAllocateReaders(pCsr, pExpr->pRight, pnToken, pnOr, pRc);
+ }
+ }
+}
+
+static int fts3EvalPhraseLoad(
+ Fts3Cursor *pCsr,
+ Fts3Phrase *p
+){
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ int iToken;
+ int rc = SQLITE_OK;
+
+ char *aDoclist = 0;
+ int nDoclist = 0;
+ int iPrev = -1;
+
+ for(iToken=0; rc==SQLITE_OK && iToken<p->nToken; iToken++){
+ Fts3PhraseToken *pToken = &p->aToken[iToken];
+ assert( pToken->pSegcsr || pToken->pDeferred );
+
+ if( pToken->pDeferred==0 ){
+ int nThis = 0;
+ char *pThis = 0;
+ rc = fts3TermSelect(pTab, pToken, p->iColumn, 1, &nThis, &pThis);
+ if( rc==SQLITE_OK ){
+ if( pThis==0 ){
+ sqlite3_free(aDoclist);
+ aDoclist = 0;
+ nDoclist = 0;
+ break;
+ }else if( aDoclist==0 ){
+ aDoclist = pThis;
+ nDoclist = nThis;
+ }else{
+ assert( iPrev>=0 );
+ fts3DoclistPhraseMerge(pTab->bDescIdx,
+ iToken-iPrev, aDoclist, nDoclist, pThis, &nThis
+ );
+ sqlite3_free(aDoclist);
+ aDoclist = pThis;
+ nDoclist = nThis;
+ }
+ iPrev = iToken;
+ }
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ p->doclist.aAll = aDoclist;
+ p->doclist.nAll = nDoclist;
+ }else{
+ sqlite3_free(aDoclist);
+ }
+ return rc;
+}
+
+static int fts3EvalDeferredPhrase(Fts3Cursor *pCsr, Fts3Phrase *pPhrase){
+ int iToken;
+ int rc = SQLITE_OK;
+
+ int nMaxUndeferred = -1;
+ char *aPoslist = 0;
+ int nPoslist = 0;
+ int iPrev = -1;
+
+ assert( pPhrase->doclist.bFreeList==0 );
+
+ for(iToken=0; rc==SQLITE_OK && iToken<pPhrase->nToken; iToken++){
+ Fts3PhraseToken *pToken = &pPhrase->aToken[iToken];
+ Fts3DeferredToken *pDeferred = pToken->pDeferred;
+
+ if( pDeferred ){
+ char *pList;
+ int nList;
+ rc = sqlite3Fts3DeferredTokenList(pDeferred, &pList, &nList);
+ if( rc!=SQLITE_OK ) return rc;
+
+ if( pList==0 ){
+ sqlite3_free(aPoslist);
+ pPhrase->doclist.pList = 0;
+ pPhrase->doclist.nList = 0;
+ return SQLITE_OK;
+
+ }else if( aPoslist==0 ){
+ aPoslist = pList;
+ nPoslist = nList;
+
+ }else{
+ assert( iPrev>=0 );
+
+ char *aOut = pList;
+ char *p1 = aPoslist;
+ char *p2 = aOut;
+
+ fts3PoslistPhraseMerge(&aOut, iToken-iPrev, 0, 1, &p1, &p2);
+ sqlite3_free(aPoslist);
+ aPoslist = pList;
+ nPoslist = aOut - aPoslist;
+ if( nPoslist==0 ){
+ sqlite3_free(aPoslist);
+ pPhrase->doclist.pList = 0;
+ pPhrase->doclist.nList = 0;
+ return SQLITE_OK;
+ }
+ }
+ iPrev = iToken;
+ }else{
+ nMaxUndeferred = iToken;
+ }
+ }
+
+ if( iPrev>=0 ){
+ if( nMaxUndeferred<0 ){
+ pPhrase->doclist.pList = aPoslist;
+ pPhrase->doclist.nList = nPoslist;
+ pPhrase->doclist.iDocid = pCsr->iPrevId;
+ pPhrase->doclist.bFreeList = 1;
+ }else{
+ int nDistance;
+ char *p1;
+ char *p2;
+ char *aOut;
+
+ if( nMaxUndeferred>iPrev ){
+ p1 = aPoslist;
+ p2 = pPhrase->doclist.pList;
+ nDistance = nMaxUndeferred - iPrev;
+ }else{
+ p1 = pPhrase->doclist.pList;
+ p2 = aPoslist;
+ nDistance = iPrev - nMaxUndeferred;
+ }
+
+ aOut = (char *)sqlite3_malloc(nPoslist+8);
+ if( !aOut ){
+ sqlite3_free(aPoslist);
+ return SQLITE_NOMEM;
+ }
+
+ pPhrase->doclist.pList = aOut;
+ if( fts3PoslistPhraseMerge(&aOut, nDistance, 0, 1, &p1, &p2) ){
+ pPhrase->doclist.bFreeList = 1;
+ pPhrase->doclist.nList = (aOut - pPhrase->doclist.pList);
+ }else{
+ sqlite3_free(aOut);
+ pPhrase->doclist.pList = 0;
+ pPhrase->doclist.nList = 0;
+ }
+ sqlite3_free(aPoslist);
+ }
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** This function is called for each Fts3Phrase in a full-text query
+** expression to initialize the mechanism for returning rows. Once this
+** function has been called successfully on an Fts3Phrase, it may be
+** used with fts3EvalPhraseNext() to iterate through the matching docids.
+*/
+static int fts3EvalPhraseStart(Fts3Cursor *pCsr, int bOptOk, Fts3Phrase *p){
+ int rc;
+ Fts3PhraseToken *pFirst = &p->aToken[0];
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+
+ assert( p->doclist.aAll==0 );
+ if( pCsr->bDesc==pTab->bDescIdx && bOptOk==1 && p->nToken==1
+ && pFirst->pSegcsr && pFirst->pSegcsr->bLookup
+ ){
+ /* Use the incremental approach. */
+ int iCol = (p->iColumn >= pTab->nColumn ? -1 : p->iColumn);
+ rc = sqlite3Fts3MsrIncrStart(
+ pTab, pFirst->pSegcsr, iCol, pFirst->z, pFirst->n);
+ p->bIncr = 1;
+
+ }else{
+ /* Load the full doclist for the phrase into memory. */
+ rc = fts3EvalPhraseLoad(pCsr, p);
+ p->bIncr = 0;
+ }
+
+ assert( rc!=SQLITE_OK || p->nToken<1 || p->aToken[0].pSegcsr==0 || p->bIncr );
+ return rc;
+}
+
+/*
+** This function is used to iterate backwards (from the end to start)
+** through doclists.
+*/
+void sqlite3Fts3DoclistPrev(
+ int bDescIdx, /* True if the doclist is desc */
+ char *aDoclist, /* Pointer to entire doclist */
+ int nDoclist, /* Length of aDoclist in bytes */
+ char **ppIter, /* IN/OUT: Iterator pointer */
+ sqlite3_int64 *piDocid, /* IN/OUT: Docid pointer */
+ int *pnList, /* IN/OUT: List length pointer */
+ u8 *pbEof /* OUT: End-of-file flag */
+){
+ char *p = *ppIter;
+ int iMul = (bDescIdx ? -1 : 1);
+
+ assert( nDoclist>0 );
+ assert( *pbEof==0 );
+ assert( p || *piDocid==0 );
+ assert( !p || (p>aDoclist && p<&aDoclist[nDoclist]) );
+
+ if( p==0 ){
+ sqlite3_int64 iDocid = 0;
+ char *pNext = 0;
+ char *pDocid = aDoclist;
+ char *pEnd = &aDoclist[nDoclist];
+
+ pDocid += sqlite3Fts3GetVarint(pDocid, &iDocid);
+ pNext = pDocid;
+ fts3PoslistCopy(0, &pDocid);
+ while( pDocid<pEnd ){
+ sqlite3_int64 iDelta;
+ pDocid += sqlite3Fts3GetVarint(pDocid, &iDelta);
+ iDocid += (iMul * iDelta);
+ pNext = pDocid;
+ fts3PoslistCopy(0, &pDocid);
+ while( pDocid<pEnd && *pDocid==0 ) pDocid++;
+ }
+
+ *pnList = pEnd - pNext;
+ *ppIter = pNext;
+ *piDocid = iDocid;
+ }else{
+ sqlite3_int64 iDelta;
+ fts3GetReverseVarint(&p, aDoclist, &iDelta);
+ *piDocid -= (iMul * iDelta);
+
+ if( p==aDoclist ){
+ *pbEof = 1;
+ }else{
+ char *pSave = p;
+ fts3ReversePoslist(aDoclist, &p);
+ *pnList = (pSave - p);
+ }
+ *ppIter = p;
+ }
+}
+
+/*
+** Attempt to move the phrase iterator to point to the next matching docid.
+** If an error occurs, return an SQLite error code. Otherwise, return
+** SQLITE_OK.
+**
+** If there is no "next" entry and no error occurs, then *pbEof is set to
+** 1 before returning. Otherwise, if no error occurs and the iterator is
+** successfully advanced, *pbEof is set to 0.
+*/
+static int fts3EvalPhraseNext(
+ Fts3Cursor *pCsr,
+ Fts3Phrase *p,
+ u8 *pbEof
+){
+ int rc = SQLITE_OK;
+ Fts3Doclist *pDL = &p->doclist;
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+
+ if( p->bIncr ){
+ assert( p->nToken==1 );
+ assert( pDL->pNextDocid==0 );
+ rc = sqlite3Fts3MsrIncrNext(pTab, p->aToken[0].pSegcsr,
+ &pDL->iDocid, &pDL->pList, &pDL->nList
+ );
+ if( rc==SQLITE_OK && !pDL->pList ){
+ *pbEof = 1;
+ }
+ }else if( pCsr->bDesc!=pTab->bDescIdx && pDL->nAll ){
+ sqlite3Fts3DoclistPrev(pTab->bDescIdx, pDL->aAll, pDL->nAll,
+ &pDL->pNextDocid, &pDL->iDocid, &pDL->nList, pbEof
+ );
+ pDL->pList = pDL->pNextDocid;
+ }else{
+ char *pIter; /* Used to iterate through aAll */
+ char *pEnd = &pDL->aAll[pDL->nAll]; /* 1 byte past end of aAll */
+ if( pDL->pNextDocid ){
+ pIter = pDL->pNextDocid;
+ }else{
+ pIter = pDL->aAll;
+ }
+
+ if( pIter>=pEnd ){
+ /* We have already reached the end of this doclist. EOF. */
+ *pbEof = 1;
+ }else{
+ sqlite3_int64 iDelta;
+ pIter += sqlite3Fts3GetVarint(pIter, &iDelta);
+ if( pTab->bDescIdx==0 || pDL->pNextDocid==0 ){
+ pDL->iDocid += iDelta;
+ }else{
+ pDL->iDocid -= iDelta;
+ }
+ pDL->pList = pIter;
+ fts3PoslistCopy(0, &pIter);
+ pDL->nList = (pIter - pDL->pList);
+
+ /* pIter now points just past the 0x00 that terminates the position-
+ ** list for document pDL->iDocid. However, if this position-list was
+ ** edited in place by fts3EvalNearTrim2(), then pIter may not actually
+ ** point to the start of the next docid value. The following line deals
+ ** with this case by advancing pIter past the zero-padding added by
+ ** fts3EvalNearTrim2(). */
+ while( pIter<pEnd && *pIter==0 ) pIter++;
+
+ pDL->pNextDocid = pIter;
+ assert( *pIter || pIter>=&pDL->aAll[pDL->nAll] );
+ *pbEof = 0;
+ }
+ }
+
+ return rc;
+}
+
+static void fts3EvalStartReaders(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pExpr,
+ int bOptOk,
+ int *pRc
+){
+ if( pExpr && SQLITE_OK==*pRc ){
+ if( pExpr->eType==FTSQUERY_PHRASE ){
+ int i;
+ int nToken = pExpr->pPhrase->nToken;
+ for(i=0; i<nToken; i++){
+ if( pExpr->pPhrase->aToken[i].pDeferred==0 ) break;
+ }
+ pExpr->bDeferred = (i==nToken);
+ *pRc = fts3EvalPhraseStart(pCsr, bOptOk, pExpr->pPhrase);
+ }else{
+ fts3EvalStartReaders(pCsr, pExpr->pLeft, bOptOk, pRc);
+ fts3EvalStartReaders(pCsr, pExpr->pRight, bOptOk, pRc);
+ pExpr->bDeferred = (pExpr->pLeft->bDeferred && pExpr->pRight->bDeferred);
+ }
+ }
+}
+
+
+typedef struct Fts3TokenAndCost Fts3TokenAndCost;
+struct Fts3TokenAndCost {
+ Fts3PhraseToken *pToken;
+ Fts3Expr *pRoot;
+ int nOvfl;
+ int iCol;
+};
+
+static void fts3EvalTokenCosts(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pRoot,
+ Fts3Expr *pExpr,
+ Fts3TokenAndCost **ppTC,
+ Fts3Expr ***ppOr,
+ int *pRc
+){
+ if( *pRc==SQLITE_OK && pExpr ){
+ if( pExpr->eType==FTSQUERY_PHRASE ){
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+ int i;
+ for(i=0; *pRc==SQLITE_OK && i<pPhrase->nToken; i++){
+ Fts3TokenAndCost *pTC = (*ppTC)++;
+ pTC->pRoot = pRoot;
+ pTC->pToken = &pPhrase->aToken[i];
+ pTC->iCol = pPhrase->iColumn;
+ *pRc = sqlite3Fts3MsrOvfl(pCsr, pTC->pToken->pSegcsr, &pTC->nOvfl);
+ }
+ }else if( pExpr->eType!=FTSQUERY_NOT ){
+ if( pExpr->eType==FTSQUERY_OR ){
+ pRoot = pExpr->pLeft;
+ **ppOr = pRoot;
+ (*ppOr)++;
+ }
+ fts3EvalTokenCosts(pCsr, pRoot, pExpr->pLeft, ppTC, ppOr, pRc);
+ if( pExpr->eType==FTSQUERY_OR ){
+ pRoot = pExpr->pRight;
+ **ppOr = pRoot;
+ (*ppOr)++;
+ }
+ fts3EvalTokenCosts(pCsr, pRoot, pExpr->pRight, ppTC, ppOr, pRc);
+ }
+ }
+}
+
+static int fts3EvalAverageDocsize(Fts3Cursor *pCsr, int *pnPage){
+ if( pCsr->nRowAvg==0 ){
+ /* The average document size, which is required to calculate the cost
+ ** of each doclist, has not yet been determined. Read the required
+ ** data from the %_stat table to calculate it.
+ **
+ ** Entry 0 of the %_stat table is a blob containing (nCol+1) FTS3
+ ** varints, where nCol is the number of columns in the FTS3 table.
+ ** The first varint is the number of documents currently stored in
+ ** the table. The following nCol varints contain the total amount of
+ ** data stored in all rows of each column of the table, from left
+ ** to right.
+ */
+ int rc;
+ Fts3Table *p = (Fts3Table*)pCsr->base.pVtab;
+ sqlite3_stmt *pStmt;
+ sqlite3_int64 nDoc = 0;
+ sqlite3_int64 nByte = 0;
+ const char *pEnd;
+ const char *a;
+
+ rc = sqlite3Fts3SelectDoctotal(p, &pStmt);
+ if( rc!=SQLITE_OK ) return rc;
+ a = sqlite3_column_blob(pStmt, 0);
+ assert( a );
+
+ pEnd = &a[sqlite3_column_bytes(pStmt, 0)];
+ a += sqlite3Fts3GetVarint(a, &nDoc);
+ while( a<pEnd ){
+ a += sqlite3Fts3GetVarint(a, &nByte);
+ }
+ if( nDoc==0 || nByte==0 ){
+ sqlite3_reset(pStmt);
+ return SQLITE_CORRUPT_VTAB;
+ }
+
+ pCsr->nDoc = nDoc;
+ pCsr->nRowAvg = (int)(((nByte / nDoc) + p->nPgsz) / p->nPgsz);
+ assert( pCsr->nRowAvg>0 );
+ rc = sqlite3_reset(pStmt);
+ if( rc!=SQLITE_OK ) return rc;
+ }
+
+ *pnPage = pCsr->nRowAvg;
+ return SQLITE_OK;
+}
+
+static int fts3EvalSelectDeferred(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pRoot,
+ Fts3TokenAndCost *aTC,
+ int nTC
+){
+ int nDocSize = 0;
+ int nDocEst = 0;
+ int rc = SQLITE_OK;
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ int ii;
+
+ int nOvfl = 0;
+ int nTerm = 0;
+
+ for(ii=0; ii<nTC; ii++){
+ if( aTC[ii].pRoot==pRoot ){
+ nOvfl += aTC[ii].nOvfl;
+ nTerm++;
+ }
+ }
+ if( nOvfl==0 || nTerm<2 ) return SQLITE_OK;
+
+ rc = fts3EvalAverageDocsize(pCsr, &nDocSize);
+
+ for(ii=0; ii<nTerm && rc==SQLITE_OK; ii++){
+ int jj;
+ Fts3TokenAndCost *pTC = 0;
+
+ for(jj=0; jj<nTC; jj++){
+ if( aTC[jj].pToken && aTC[jj].pRoot==pRoot
+ && (!pTC || aTC[jj].nOvfl<pTC->nOvfl)
+ ){
+ pTC = &aTC[jj];
+ }
+ }
+ assert( pTC );
+
+ /* At this point pTC points to the cheapest remaining token. */
+ if( ii==0 ){
+ if( pTC->nOvfl ){
+ nDocEst = (pTC->nOvfl * pTab->nPgsz + pTab->nPgsz) / 10;
+ }else{
+ /* TODO: Fix this so that the doclist need not be read twice. */
+ Fts3PhraseToken *pToken = pTC->pToken;
+ int nList = 0;
+ char *pList = 0;
+ rc = fts3TermSelect(pTab, pToken, pTC->iCol, 1, &nList, &pList);
+ if( rc==SQLITE_OK ){
+ nDocEst = fts3DoclistCountDocids(1, pList, nList);
+ }
+ sqlite3_free(pList);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3Fts3TermSegReaderCursor(pCsr,
+ pToken->z, pToken->n, pToken->isPrefix, &pToken->pSegcsr
+ );
+ }
+ }
+ }else{
+ if( pTC->nOvfl>=(nDocEst*nDocSize) ){
+ Fts3PhraseToken *pToken = pTC->pToken;
+ rc = sqlite3Fts3DeferToken(pCsr, pToken, pTC->iCol);
+ fts3SegReaderCursorFree(pToken->pSegcsr);
+ pToken->pSegcsr = 0;
+ }
+ nDocEst = 1 + (nDocEst/4);
+ }
+ pTC->pToken = 0;
+ }
+
+ return rc;
+}
+
+int sqlite3Fts3EvalStart(Fts3Cursor *pCsr, Fts3Expr *pExpr, int bOptOk){
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ int rc = SQLITE_OK;
+ int nToken = 0;
+ int nOr = 0;
+
+ /* Allocate a MultiSegReader for each token in the expression. */
+ fts3EvalAllocateReaders(pCsr, pExpr, &nToken, &nOr, &rc);
+
+ /* Call fts3EvalPhraseStart() on all phrases in the expression. TODO:
+ ** This call will eventually also be responsible for determining which
+ ** tokens are 'deferred' until the document text is loaded into memory.
+ **
+ ** Each token in each phrase is dealt with using one of the following
+ ** three strategies:
+ **
+ ** 1. Entire doclist loaded into memory as part of the
+ ** fts3EvalStartReaders() call.
+ **
+ ** 2. Doclist loaded into memory incrementally, as part of each
+ ** sqlite3Fts3EvalNext() call.
+ **
+ ** 3. Token doclist is never loaded. Instead, documents are loaded into
+ ** memory and scanned for the token as part of the sqlite3Fts3EvalNext()
+ ** call. This is known as a "deferred" token.
+ */
+
+ /* If bOptOk is true, check if there are any tokens that should be deferred.
+ */
+ if( rc==SQLITE_OK && bOptOk && nToken>1 && pTab->bHasStat ){
+ Fts3TokenAndCost *aTC;
+ Fts3Expr **apOr;
+ aTC = (Fts3TokenAndCost *)sqlite3_malloc(
+ sizeof(Fts3TokenAndCost) * nToken
+ + sizeof(Fts3Expr *) * nOr * 2
+ );
+ apOr = (Fts3Expr **)&aTC[nToken];
+
+ if( !aTC ){
+ rc = SQLITE_NOMEM;
+ }else{
+ int ii;
+ Fts3TokenAndCost *pTC = aTC;
+ Fts3Expr **ppOr = apOr;
+
+ fts3EvalTokenCosts(pCsr, 0, pExpr, &pTC, &ppOr, &rc);
+ nToken = pTC-aTC;
+ nOr = ppOr-apOr;
+
+ if( rc==SQLITE_OK ){
+ rc = fts3EvalSelectDeferred(pCsr, 0, aTC, nToken);
+ for(ii=0; rc==SQLITE_OK && ii<nOr; ii++){
+ rc = fts3EvalSelectDeferred(pCsr, apOr[ii], aTC, nToken);
+ }
+ }
+
+ sqlite3_free(aTC);
+ }
+ }
+
+ fts3EvalStartReaders(pCsr, pExpr, bOptOk, &rc);
+ return rc;
+}
+
+static void fts3EvalZeroPoslist(Fts3Phrase *pPhrase){
+ if( pPhrase->doclist.bFreeList ){
+ sqlite3_free(pPhrase->doclist.pList);
+ }
+ pPhrase->doclist.pList = 0;
+ pPhrase->doclist.nList = 0;
+ pPhrase->doclist.bFreeList = 0;
+}
+
+static int fts3EvalNearTrim2(
+ int nNear,
+ char *aTmp, /* Temporary space to use */
+ char **paPoslist, /* IN/OUT: Position list */
+ int *pnToken, /* IN/OUT: Tokens in phrase of *paPoslist */
+ Fts3Phrase *pPhrase /* The phrase object to trim the doclist of */
+){
+ int nParam1 = nNear + pPhrase->nToken;
+ int nParam2 = nNear + *pnToken;
+ int nNew;
+ char *p2;
+ char *pOut;
+ int res;
+
+ assert( pPhrase->doclist.pList );
+
+ p2 = pOut = pPhrase->doclist.pList;
+ res = fts3PoslistNearMerge(
+ &pOut, aTmp, nParam1, nParam2, paPoslist, &p2
+ );
+ if( res ){
+ nNew = (pOut - pPhrase->doclist.pList) - 1;
+ assert( pPhrase->doclist.pList[nNew]=='\0' );
+ assert( nNew<=pPhrase->doclist.nList && nNew>0 );
+ memset(&pPhrase->doclist.pList[nNew], 0, pPhrase->doclist.nList - nNew);
+ pPhrase->doclist.nList = nNew;
+ *paPoslist = pPhrase->doclist.pList;
+ *pnToken = pPhrase->nToken;
+ }
+
+ return res;
+}
+
+static int fts3EvalNearTest(Fts3Expr *pExpr, int *pRc){
+ int res = 1;
+
+ /* The following block runs if pExpr is the root of a NEAR query.
+ ** For example, the query:
+ **
+ ** "w" NEAR "x" NEAR "y" NEAR "z"
+ **
+ ** which is represented in tree form as:
+ **
+ ** |
+ ** +--NEAR--+ <-- root of NEAR query
+ ** | |
+ ** +--NEAR--+ "z"
+ ** | |
+ ** +--NEAR--+ "y"
+ ** | |
+ ** "w" "x"
+ **
+ ** The right-hand child of a NEAR node is always a phrase. The
+ ** left-hand child may be either a phrase or a NEAR node. There are
+ ** no exceptions to this.
+ */
+ if( *pRc==SQLITE_OK
+ && pExpr->eType==FTSQUERY_NEAR
+ && pExpr->bEof==0
+ && (pExpr->pParent==0 || pExpr->pParent->eType!=FTSQUERY_NEAR)
+ ){
+ Fts3Expr *p;
+ int nTmp = 0; /* Bytes of temp space */
+ char *aTmp; /* Temp space for PoslistNearMerge() */
+
+ /* Allocate temporary working space. */
+ for(p=pExpr; p->pLeft; p=p->pLeft){
+ nTmp += p->pRight->pPhrase->doclist.nList;
+ }
+ nTmp += p->pPhrase->doclist.nList;
+ aTmp = sqlite3_malloc(nTmp*2);
+ if( !aTmp ){
+ *pRc = SQLITE_NOMEM;
+ res = 0;
+ }else{
+ char *aPoslist = p->pPhrase->doclist.pList;
+ int nToken = p->pPhrase->nToken;
+
+ for(p=p->pParent;res && p && p->eType==FTSQUERY_NEAR; p=p->pParent){
+ Fts3Phrase *pPhrase = p->pRight->pPhrase;
+ int nNear = p->nNear;
+ res = fts3EvalNearTrim2(nNear, aTmp, &aPoslist, &nToken, pPhrase);
+ }
+
+ aPoslist = pExpr->pRight->pPhrase->doclist.pList;
+ nToken = pExpr->pRight->pPhrase->nToken;
+ for(p=pExpr->pLeft; p && res; p=p->pLeft){
+ int nNear = p->pParent->nNear;
+ Fts3Phrase *pPhrase = (
+ p->eType==FTSQUERY_NEAR ? p->pRight->pPhrase : p->pPhrase
+ );
+ res = fts3EvalNearTrim2(nNear, aTmp, &aPoslist, &nToken, pPhrase);
+ }
+ }
+
+ sqlite3_free(aTmp);
+ }
+
+ return res;
+}
+
+/*
+** This macro is used by the fts3EvalNext() function. The two arguments are
+** 64-bit docid values. If the current query is "ORDER BY docid ASC", then
+** the macro returns (i1 - i2). Or if it is "ORDER BY docid DESC", then
+** it returns (i2 - i1). This allows the same code to be used for merging
+** doclists in ascending or descending order.
+*/
+#define DOCID_CMP(i1, i2) ((pCsr->bDesc?-1:1) * (i1-i2))
+
+static void fts3EvalNext(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pExpr,
+ int *pRc
+){
+ if( *pRc==SQLITE_OK ){
+ assert( pExpr->bEof==0 );
+ pExpr->bStart = 1;
+
+ switch( pExpr->eType ){
+ case FTSQUERY_NEAR:
+ case FTSQUERY_AND: {
+ Fts3Expr *pLeft = pExpr->pLeft;
+ Fts3Expr *pRight = pExpr->pRight;
+ assert( !pLeft->bDeferred || !pRight->bDeferred );
+ if( pLeft->bDeferred ){
+ fts3EvalNext(pCsr, pRight, pRc);
+ pExpr->iDocid = pRight->iDocid;
+ pExpr->bEof = pRight->bEof;
+ }else if( pRight->bDeferred ){
+ fts3EvalNext(pCsr, pLeft, pRc);
+ pExpr->iDocid = pLeft->iDocid;
+ pExpr->bEof = pLeft->bEof;
+ }else{
+ fts3EvalNext(pCsr, pLeft, pRc);
+ fts3EvalNext(pCsr, pRight, pRc);
+
+ while( !pLeft->bEof && !pRight->bEof && *pRc==SQLITE_OK ){
+ sqlite3_int64 iDiff = DOCID_CMP(pLeft->iDocid, pRight->iDocid);
+ if( iDiff==0 ) break;
+ if( iDiff<0 ){
+ fts3EvalNext(pCsr, pLeft, pRc);
+ }else{
+ fts3EvalNext(pCsr, pRight, pRc);
+ }
+ }
+
+ pExpr->iDocid = pLeft->iDocid;
+ pExpr->bEof = (pLeft->bEof || pRight->bEof);
+ }
+ break;
+ }
+
+ case FTSQUERY_OR: {
+ Fts3Expr *pLeft = pExpr->pLeft;
+ Fts3Expr *pRight = pExpr->pRight;
+ sqlite3_int64 iCmp = DOCID_CMP(pLeft->iDocid, pRight->iDocid);
+
+ assert( pLeft->bStart || pLeft->iDocid==pRight->iDocid );
+ assert( pRight->bStart || pLeft->iDocid==pRight->iDocid );
+
+ if( pRight->bEof || (pLeft->bEof==0 && iCmp<0) ){
+ fts3EvalNext(pCsr, pLeft, pRc);
+ }else if( pLeft->bEof || (pRight->bEof==0 && iCmp>0) ){
+ fts3EvalNext(pCsr, pRight, pRc);
+ }else{
+ fts3EvalNext(pCsr, pLeft, pRc);
+ fts3EvalNext(pCsr, pRight, pRc);
+ }
+
+ pExpr->bEof = (pLeft->bEof && pRight->bEof);
+ iCmp = DOCID_CMP(pLeft->iDocid, pRight->iDocid);
+ if( pRight->bEof || (pLeft->bEof==0 && iCmp<0) ){
+ pExpr->iDocid = pLeft->iDocid;
+ }else{
+ pExpr->iDocid = pRight->iDocid;
+ }
+
+ break;
+ }
+
+ case FTSQUERY_NOT: {
+ Fts3Expr *pLeft = pExpr->pLeft;
+ Fts3Expr *pRight = pExpr->pRight;
+
+ if( pRight->bStart==0 ){
+ fts3EvalNext(pCsr, pRight, pRc);
+ assert( *pRc!=SQLITE_OK || pRight->bStart );
+ }
+
+ fts3EvalNext(pCsr, pLeft, pRc);
+ if( pLeft->bEof==0 ){
+ while( !*pRc
+ && !pRight->bEof
+ && DOCID_CMP(pLeft->iDocid, pRight->iDocid)>0
+ ){
+ fts3EvalNext(pCsr, pRight, pRc);
+ }
+ }
+ pExpr->iDocid = pLeft->iDocid;
+ pExpr->bEof = pLeft->bEof;
+ break;
+ }
+
+ default: {
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+ fts3EvalZeroPoslist(pPhrase);
+ *pRc = fts3EvalPhraseNext(pCsr, pPhrase, &pExpr->bEof);
+ pExpr->iDocid = pPhrase->doclist.iDocid;
+ break;
+ }
+ }
+ }
+}
+
+static int fts3EvalDeferredTest(Fts3Cursor *pCsr, Fts3Expr *pExpr, int *pRc){
+ int bHit = 1;
+ if( *pRc==SQLITE_OK ){
+ switch( pExpr->eType ){
+ case FTSQUERY_NEAR:
+ case FTSQUERY_AND:
+ bHit = (
+ fts3EvalDeferredTest(pCsr, pExpr->pLeft, pRc)
+ && fts3EvalDeferredTest(pCsr, pExpr->pRight, pRc)
+ && fts3EvalNearTest(pExpr, pRc)
+ );
+
+ /* If the NEAR expression does not match any rows, zero the doclist for
+ ** all phrases involved in the NEAR. This is because the snippet(),
+ ** offsets() and matchinfo() functions are not supposed to recognize
+ ** any instances of phrases that are part of unmatched NEAR queries.
+ ** For example if this expression:
+ **
+ ** ... MATCH 'a OR (b NEAR c)'
+ **
+ ** is matched against a row containing:
+ **
+ ** 'a b d e'
+ **
+ ** then any snippet() should ony highlight the "a" term, not the "b"
+ ** (as "b" is part of a non-matching NEAR clause).
+ */
+ if( bHit==0
+ && pExpr->eType==FTSQUERY_NEAR
+ && (pExpr->pParent==0 || pExpr->pParent->eType!=FTSQUERY_NEAR)
+ ){
+ Fts3Expr *p;
+ for(p=pExpr; p->pPhrase==0; p=p->pLeft){
+ if( p->pRight->iDocid==pCsr->iPrevId ){
+ fts3EvalZeroPoslist(p->pRight->pPhrase);
+ }
+ }
+ if( p->iDocid==pCsr->iPrevId ){
+ fts3EvalZeroPoslist(p->pPhrase);
+ }
+ }
+
+ break;
+
+ case FTSQUERY_OR: {
+ int bHit1 = fts3EvalDeferredTest(pCsr, pExpr->pLeft, pRc);
+ int bHit2 = fts3EvalDeferredTest(pCsr, pExpr->pRight, pRc);
+ bHit = bHit1 || bHit2;
+ break;
+ }
+
+ case FTSQUERY_NOT:
+ bHit = (
+ fts3EvalDeferredTest(pCsr, pExpr->pLeft, pRc)
+ && !fts3EvalDeferredTest(pCsr, pExpr->pRight, pRc)
+ );
+ break;
+
+ default: {
+ if( pCsr->pDeferred
+ && (pExpr->iDocid==pCsr->iPrevId || pExpr->bDeferred)
+ ){
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+ assert( pExpr->bDeferred || pPhrase->doclist.bFreeList==0 );
+ if( pExpr->bDeferred ){
+ fts3EvalZeroPoslist(pPhrase);
+ }
+ *pRc = fts3EvalDeferredPhrase(pCsr, pPhrase);
+ bHit = (pPhrase->doclist.pList!=0);
+ pExpr->iDocid = pCsr->iPrevId;
+ }else{
+ bHit = (pExpr->bEof==0 && pExpr->iDocid==pCsr->iPrevId);
+ }
+ break;
+ }
+ }
+ }
+ return bHit;
+}
+
+/*
+** Return 1 if both of the following are true:
+**
+** 1. *pRc is SQLITE_OK when this function returns, and
+**
+** 2. After scanning the current FTS table row for the deferred tokens,
+** it is determined that the row does not match the query.
+**
+** Or, if no error occurs and it seems the current row does match the FTS
+** query, return 0.
+*/
+static int fts3EvalLoadDeferred(Fts3Cursor *pCsr, int *pRc){
+ int rc = *pRc;
+ int bMiss = 0;
+ if( rc==SQLITE_OK ){
+ if( pCsr->pDeferred ){
+ rc = fts3CursorSeek(0, pCsr);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3Fts3CacheDeferredDoclists(pCsr);
+ }
+ }
+ bMiss = (0==fts3EvalDeferredTest(pCsr, pCsr->pExpr, &rc));
+ sqlite3Fts3FreeDeferredDoclists(pCsr);
+ *pRc = rc;
+ }
+ return (rc==SQLITE_OK && bMiss);
+}
+
+/*
+** Advance to the next document that matches the FTS expression in
+** Fts3Cursor.pExpr.
+*/
+int sqlite3Fts3EvalNext(Fts3Cursor *pCsr){
+ int rc = SQLITE_OK; /* Return Code */
+ Fts3Expr *pExpr = pCsr->pExpr;
+ assert( pCsr->isEof==0 );
+ if( pExpr==0 ){
+ pCsr->isEof = 1;
+ }else{
+ do {
+ if( pCsr->isRequireSeek==0 ){
+ sqlite3_reset(pCsr->pStmt);
+ }
+ assert( sqlite3_data_count(pCsr->pStmt)==0 );
+ fts3EvalNext(pCsr, pExpr, &rc);
+ pCsr->isEof = pExpr->bEof;
+ pCsr->isRequireSeek = 1;
+ pCsr->isMatchinfoNeeded = 1;
+ pCsr->iPrevId = pExpr->iDocid;
+ }while( pCsr->isEof==0 && fts3EvalLoadDeferred(pCsr, &rc) );
+ }
+ return rc;
+}
+
++/*
++** Restart interation for expression pExpr so that the next call to
++** sqlite3Fts3EvalNext() visits the first row. Do not allow incremental
++** loading or merging of phrase doclists for this iteration.
++**
++** If *pRc is other than SQLITE_OK when this function is called, it is
++** a no-op. If an error occurs within this function, *pRc is set to an
++** SQLite error code before returning.
++*/
+static void fts3EvalRestart(
+ Fts3Cursor *pCsr,
+ Fts3Expr *pExpr,
+ int *pRc
+){
+ if( pExpr && *pRc==SQLITE_OK ){
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+
+ if( pPhrase ){
+ fts3EvalZeroPoslist(pPhrase);
+ if( pPhrase->bIncr ){
+ sqlite3Fts3EvalPhraseCleanup(pPhrase);
+ memset(&pPhrase->doclist, 0, sizeof(Fts3Doclist));
+ *pRc = sqlite3Fts3EvalStart(pCsr, pExpr, 0);
+ }else{
+ pPhrase->doclist.pNextDocid = 0;
+ pPhrase->doclist.iDocid = 0;
+ }
+ }
+
+ pExpr->iDocid = 0;
+ pExpr->bEof = 0;
+ pExpr->bStart = 0;
+
+ fts3EvalRestart(pCsr, pExpr->pLeft, pRc);
+ fts3EvalRestart(pCsr, pExpr->pRight, pRc);
+ }
+}
+
+/*
+** After allocating the Fts3Expr.aMI[] array for each phrase in the
+** expression rooted at pExpr, the cursor iterates through all rows matched
+** by pExpr, calling this function for each row. This function increments
+** the values in Fts3Expr.aMI[] according to the position-list currently
+** found in Fts3Expr.pPhrase->doclist.pList for each of the phrase
+** expression nodes.
+*/
+static void fts3EvalUpdateCounts(Fts3Expr *pExpr){
+ if( pExpr ){
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+ if( pPhrase && pPhrase->doclist.pList ){
+ int iCol = 0;
+ char *p = pPhrase->doclist.pList;
+
+ assert( *p );
+ while( 1 ){
+ u8 c = 0;
+ int iCnt = 0;
+ while( 0xFE & (*p | c) ){
+ if( (c&0x80)==0 ) iCnt++;
+ c = *p++ & 0x80;
+ }
+
+ /* aMI[iCol*3 + 1] = Number of occurrences
+ ** aMI[iCol*3 + 2] = Number of rows containing at least one instance
+ */
+ pExpr->aMI[iCol*3 + 1] += iCnt;
+ pExpr->aMI[iCol*3 + 2] += (iCnt>0);
+ if( *p==0x00 ) break;
+ p++;
+ p += sqlite3Fts3GetVarint32(p, &iCol);
+ }
+ }
+
+ fts3EvalUpdateCounts(pExpr->pLeft);
+ fts3EvalUpdateCounts(pExpr->pRight);
+ }
+}
+
+/*
+** Expression pExpr must be of type FTSQUERY_PHRASE.
+**
+** If it is not already allocated and populated, this function allocates and
+** populates the Fts3Expr.aMI[] array for expression pExpr. If pExpr is part
+** of a NEAR expression, then it also allocates and populates the same array
+** for all other phrases that are part of the NEAR expression.
+**
+** SQLITE_OK is returned if the aMI[] array is successfully allocated and
+** populated. Otherwise, if an error occurs, an SQLite error code is returned.
+*/
+static int fts3EvalGatherStats(
+ Fts3Cursor *pCsr, /* Cursor object */
+ Fts3Expr *pExpr /* FTSQUERY_PHRASE expression */
+){
+ int rc = SQLITE_OK; /* Return code */
+
+ assert( pExpr->eType==FTSQUERY_PHRASE );
+ if( pExpr->aMI==0 ){
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ Fts3Expr *pRoot; /* Root of NEAR expression */
+ Fts3Expr *p; /* Iterator used for several purposes */
+
+ sqlite3_int64 iPrevId = pCsr->iPrevId;
+ sqlite3_int64 iDocid;
+ u8 bEof;
+
+ /* Find the root of the NEAR expression */
+ pRoot = pExpr;
+ while( pRoot->pParent && pRoot->pParent->eType==FTSQUERY_NEAR ){
+ pRoot = pRoot->pParent;
+ }
+ iDocid = pRoot->iDocid;
+ bEof = pRoot->bEof;
+ assert( pRoot->bStart );
+
+ /* Allocate space for the aMSI[] array of each FTSQUERY_PHRASE node */
+ for(p=pRoot; p; p=p->pLeft){
+ Fts3Expr *pE = (p->eType==FTSQUERY_PHRASE?p:p->pRight);
+ assert( pE->aMI==0 );
+ pE->aMI = (u32 *)sqlite3_malloc(pTab->nColumn * 3 * sizeof(u32));
+ if( !pE->aMI ) return SQLITE_NOMEM;
+ memset(pE->aMI, 0, pTab->nColumn * 3 * sizeof(u32));
+ }
+
+ fts3EvalRestart(pCsr, pRoot, &rc);
+
+ while( pCsr->isEof==0 && rc==SQLITE_OK ){
+
+ do {
+ /* Ensure the %_content statement is reset. */
+ if( pCsr->isRequireSeek==0 ) sqlite3_reset(pCsr->pStmt);
+ assert( sqlite3_data_count(pCsr->pStmt)==0 );
+
+ /* Advance to the next document */
+ fts3EvalNext(pCsr, pRoot, &rc);
+ pCsr->isEof = pRoot->bEof;
+ pCsr->isRequireSeek = 1;
+ pCsr->isMatchinfoNeeded = 1;
+ pCsr->iPrevId = pRoot->iDocid;
+ }while( pCsr->isEof==0
+ && pRoot->eType==FTSQUERY_NEAR
+ && fts3EvalLoadDeferred(pCsr, &rc)
+ );
+
+ if( rc==SQLITE_OK && pCsr->isEof==0 ){
+ fts3EvalUpdateCounts(pRoot);
+ }
+ }
+
+ pCsr->isEof = 0;
+ pCsr->iPrevId = iPrevId;
+
+ if( bEof ){
+ pRoot->bEof = bEof;
+ }else{
+ /* Caution: pRoot may iterate through docids in ascending or descending
+ ** order. For this reason, even though it seems more defensive, the
+ ** do loop can not be written:
+ **
+ ** do {...} while( pRoot->iDocid<iDocid && rc==SQLITE_OK );
+ */
+ fts3EvalRestart(pCsr, pRoot, &rc);
+ do {
+ fts3EvalNext(pCsr, pRoot, &rc);
+ assert( pRoot->bEof==0 );
+ }while( pRoot->iDocid!=iDocid && rc==SQLITE_OK );
+ fts3EvalLoadDeferred(pCsr, &rc);
+ }
+ }
+ return rc;
+}
+
+/*
+** This function is used by the matchinfo() module to query a phrase
+** expression node for the following information:
+**
+** 1. The total number of occurrences of the phrase in each column of
+** the FTS table (considering all rows), and
+**
+** 2. For each column, the number of rows in the table for which the
+** column contains at least one instance of the phrase.
+**
+** If no error occurs, SQLITE_OK is returned and the values for each column
+** written into the array aiOut as follows:
+**
+** aiOut[iCol*3 + 1] = Number of occurrences
+** aiOut[iCol*3 + 2] = Number of rows containing at least one instance
+**
+** Caveats:
+**
+** * If a phrase consists entirely of deferred tokens, then all output
+** values are set to the number of documents in the table. In other
+** words we assume that very common tokens occur exactly once in each
+** column of each row of the table.
+**
+** * If a phrase contains some deferred tokens (and some non-deferred
+** tokens), count the potential occurrence identified by considering
+** the non-deferred tokens instead of actual phrase occurrences.
+**
+** * If the phrase is part of a NEAR expression, then only phrase instances
+** that meet the NEAR constraint are included in the counts.
+*/
+int sqlite3Fts3EvalPhraseStats(
+ Fts3Cursor *pCsr, /* FTS cursor handle */
+ Fts3Expr *pExpr, /* Phrase expression */
+ u32 *aiOut /* Array to write results into (see above) */
+){
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ int rc = SQLITE_OK;
+ int iCol;
+
+ if( pExpr->bDeferred && pExpr->pParent->eType!=FTSQUERY_NEAR ){
+ assert( pCsr->nDoc>0 );
+ for(iCol=0; iCol<pTab->nColumn; iCol++){
+ aiOut[iCol*3 + 1] = pCsr->nDoc;
+ aiOut[iCol*3 + 2] = pCsr->nDoc;
+ }
+ }else{
+ rc = fts3EvalGatherStats(pCsr, pExpr);
+ if( rc==SQLITE_OK ){
+ assert( pExpr->aMI );
+ for(iCol=0; iCol<pTab->nColumn; iCol++){
+ aiOut[iCol*3 + 1] = pExpr->aMI[iCol*3 + 1];
+ aiOut[iCol*3 + 2] = pExpr->aMI[iCol*3 + 2];
+ }
+ }
+ }
+
+ return rc;
+}
+
+/*
+** The expression pExpr passed as the second argument to this function
+** must be of type FTSQUERY_PHRASE.
+**
+** The returned value is either NULL or a pointer to a buffer containing
+** a position-list indicating the occurrences of the phrase in column iCol
+** of the current row.
+**
+** More specifically, the returned buffer contains 1 varint for each
+** occurence of the phrase in the column, stored using the normal (delta+2)
+** compression and is terminated by either an 0x01 or 0x00 byte. For example,
+** if the requested column contains "a b X c d X X" and the position-list
+** for 'X' is requested, the buffer returned may contain:
+**
+** 0x04 0x05 0x03 0x01 or 0x04 0x05 0x03 0x00
+**
+** This function works regardless of whether or not the phrase is deferred,
+** incremental, or neither.
+*/
+char *sqlite3Fts3EvalPhrasePoslist(
+ Fts3Cursor *pCsr, /* FTS3 cursor object */
+ Fts3Expr *pExpr, /* Phrase to return doclist for */
+ int iCol /* Column to return position list for */
+){
+ Fts3Phrase *pPhrase = pExpr->pPhrase;
+ Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
+ char *pIter = pPhrase->doclist.pList;
+ int iThis;
+
+ assert( iCol>=0 && iCol<pTab->nColumn );
+ if( !pIter
+ || pExpr->bEof
+ || pExpr->iDocid!=pCsr->iPrevId
+ || (pPhrase->iColumn<pTab->nColumn && pPhrase->iColumn!=iCol)
+ ){
+ return 0;
+ }
+
+ assert( pPhrase->doclist.nList>0 );
+ if( *pIter==0x01 ){
+ pIter++;
+ pIter += sqlite3Fts3GetVarint32(pIter, &iThis);
+ }else{
+ iThis = 0;
+ }
+ while( iThis<iCol ){
+ fts3ColumnlistCopy(0, &pIter);
+ if( *pIter==0x00 ) return 0;
+ pIter++;
+ pIter += sqlite3Fts3GetVarint32(pIter, &iThis);
+ }
+
+ return ((iCol==iThis)?pIter:0);
+}
+
+/*
+** Free all components of the Fts3Phrase structure that were allocated by
+** the eval module. Specifically, this means to free:
+**
+** * the contents of pPhrase->doclist, and
+** * any Fts3MultiSegReader objects held by phrase tokens.
+*/
+void sqlite3Fts3EvalPhraseCleanup(Fts3Phrase *pPhrase){
+ if( pPhrase ){
+ int i;
+ sqlite3_free(pPhrase->doclist.aAll);
+ fts3EvalZeroPoslist(pPhrase);
+ memset(&pPhrase->doclist, 0, sizeof(Fts3Doclist));
+ for(i=0; i<pPhrase->nToken; i++){
+ fts3SegReaderCursorFree(pPhrase->aToken[i].pSegcsr);
+ pPhrase->aToken[i].pSegcsr = 0;
+ }
+ }
+}
+
#endif
projects / thirdparty / sqlite.git / commitdiff
