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diff --git a/ext/fts3/fts3_term.c b/ext/fts3/fts3_term.c
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+/*
+** 2011 Jan 27
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file is not part of the production FTS code. It is only used for
+** testing. It contains a virtual table implementation that provides direct
+** access to the full-text index of an FTS table.
+*/
+
+#include "fts3Int.h"
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+#ifdef SQLITE_TEST
+
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+
+typedef struct Fts3termTable Fts3termTable;
+typedef struct Fts3termCursor Fts3termCursor;
+
+struct Fts3termTable {
+ sqlite3_vtab base; /* Base class used by SQLite core */
+ int iIndex; /* Index for Fts3Table.aIndex[] */
+ Fts3Table *pFts3Tab;
+};
+
+struct Fts3termCursor {
+ sqlite3_vtab_cursor base; /* Base class used by SQLite core */
+ Fts3MultiSegReader csr; /* Must be right after "base" */
+ Fts3SegFilter filter;
+
+ int isEof; /* True if cursor is at EOF */
+ char *pNext;
+
+ sqlite3_int64 iRowid; /* Current 'rowid' value */
+ sqlite3_int64 iDocid; /* Current 'docid' value */
+ int iCol; /* Current 'col' value */
+ int iPos; /* Current 'pos' value */
+};
+
+/*
+** Schema of the terms table.
+*/
+#define FTS3_TERMS_SCHEMA "CREATE TABLE x(term, docid, col, pos)"
+
+/*
+** This function does all the work for both the xConnect and xCreate methods.
+** These tables have no persistent representation of their own, so xConnect
+** and xCreate are identical operations.
+*/
+static int fts3termConnectMethod(
+ sqlite3 *db, /* Database connection */
+ void *pCtx, /* Non-zero for an fts4prefix table */
+ int argc, /* Number of elements in argv array */
+ const char * const *argv, /* xCreate/xConnect argument array */
+ sqlite3_vtab **ppVtab, /* OUT: New sqlite3_vtab object */
+ char **pzErr /* OUT: sqlite3_malloc'd error message */
+){
+ char const *zDb; /* Name of database (e.g. "main") */
+ char const *zFts3; /* Name of fts3 table */
+ int nDb; /* Result of strlen(zDb) */
+ int nFts3; /* Result of strlen(zFts3) */
+ sqlite3_int64 nByte; /* Bytes of space to allocate here */
+ int rc; /* value returned by declare_vtab() */
+ Fts3termTable *p; /* Virtual table object to return */
+ int iIndex = 0;
+
+ UNUSED_PARAMETER(pCtx);
+ if( argc==5 ){
+ iIndex = atoi(argv[4]);
+ argc--;
+ }
+
+ /* The user should specify a single argument - the name of an fts3 table. */
+ if( argc!=4 ){
+ sqlite3Fts3ErrMsg(pzErr,
+ "wrong number of arguments to fts4term constructor"
+ );
+ return SQLITE_ERROR;
+ }
+
+ zDb = argv[1];
+ nDb = (int)strlen(zDb);
+ zFts3 = argv[3];
+ nFts3 = (int)strlen(zFts3);
+
+ rc = sqlite3_declare_vtab(db, FTS3_TERMS_SCHEMA);
+ if( rc!=SQLITE_OK ) return rc;
+
+ nByte = sizeof(Fts3termTable) + sizeof(Fts3Table) + nDb + nFts3 + 2;
+ p = (Fts3termTable *)sqlite3_malloc64(nByte);
+ if( !p ) return SQLITE_NOMEM;
+ memset(p, 0, (size_t)nByte);
+
+ p->pFts3Tab = (Fts3Table *)&p[1];
+ p->pFts3Tab->zDb = (char *)&p->pFts3Tab[1];
+ p->pFts3Tab->zName = &p->pFts3Tab->zDb[nDb+1];
+ p->pFts3Tab->db = db;
+ p->pFts3Tab->nIndex = iIndex+1;
+ p->iIndex = iIndex;
+
+ memcpy((char *)p->pFts3Tab->zDb, zDb, nDb);
+ memcpy((char *)p->pFts3Tab->zName, zFts3, nFts3);
+ sqlite3Fts3Dequote((char *)p->pFts3Tab->zName);
+
+ *ppVtab = (sqlite3_vtab *)p;
+ return SQLITE_OK;
+}
+
+/*
+** This function does the work for both the xDisconnect and xDestroy methods.
+** These tables have no persistent representation of their own, so xDisconnect
+** and xDestroy are identical operations.
+*/
+static int fts3termDisconnectMethod(sqlite3_vtab *pVtab){
+ Fts3termTable *p = (Fts3termTable *)pVtab;
+ Fts3Table *pFts3 = p->pFts3Tab;
+ int i;
+
+ /* Free any prepared statements held */
+ for(i=0; i<SizeofArray(pFts3->aStmt); i++){
+ sqlite3_finalize(pFts3->aStmt[i]);
+ }
+ sqlite3_free(pFts3->zSegmentsTbl);
+ sqlite3_free(p);
+ return SQLITE_OK;
+}
+
+#define FTS4AUX_EQ_CONSTRAINT 1
+#define FTS4AUX_GE_CONSTRAINT 2
+#define FTS4AUX_LE_CONSTRAINT 4
+
+/*
+** xBestIndex - Analyze a WHERE and ORDER BY clause.
+*/
+static int fts3termBestIndexMethod(
+ sqlite3_vtab *pVTab,
+ sqlite3_index_info *pInfo
+){
+ UNUSED_PARAMETER(pVTab);
+
+ /* This vtab naturally does "ORDER BY term, docid, col, pos". */
+ if( pInfo->nOrderBy ){
+ int i;
+ for(i=0; i<pInfo->nOrderBy; i++){
+ if( pInfo->aOrderBy[i].iColumn!=i || pInfo->aOrderBy[i].desc ) break;
+ }
+ if( i==pInfo->nOrderBy ){
+ pInfo->orderByConsumed = 1;
+ }
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** xOpen - Open a cursor.
+*/
+static int fts3termOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
+ Fts3termCursor *pCsr; /* Pointer to cursor object to return */
+
+ UNUSED_PARAMETER(pVTab);
+
+ pCsr = (Fts3termCursor *)sqlite3_malloc(sizeof(Fts3termCursor));
+ if( !pCsr ) return SQLITE_NOMEM;
+ memset(pCsr, 0, sizeof(Fts3termCursor));
+
+ *ppCsr = (sqlite3_vtab_cursor *)pCsr;
+ return SQLITE_OK;
+}
+
+/*
+** xClose - Close a cursor.
+*/
+static int fts3termCloseMethod(sqlite3_vtab_cursor *pCursor){
+ Fts3Table *pFts3 = ((Fts3termTable *)pCursor->pVtab)->pFts3Tab;
+ Fts3termCursor *pCsr = (Fts3termCursor *)pCursor;
+
+ sqlite3Fts3SegmentsClose(pFts3);
+ sqlite3Fts3SegReaderFinish(&pCsr->csr);
+ sqlite3_free(pCsr);
+ return SQLITE_OK;
+}
+
+/*
+** xNext - Advance the cursor to the next row, if any.
+*/
+static int fts3termNextMethod(sqlite3_vtab_cursor *pCursor){
+ Fts3termCursor *pCsr = (Fts3termCursor *)pCursor;
+ Fts3Table *pFts3 = ((Fts3termTable *)pCursor->pVtab)->pFts3Tab;
+ int rc;
+ sqlite3_int64 v;
+
+ /* Increment our pretend rowid value. */
+ pCsr->iRowid++;
+
+ /* Advance to the next term in the full-text index. */
+ if( pCsr->csr.aDoclist==0
+ || pCsr->pNext>=&pCsr->csr.aDoclist[pCsr->csr.nDoclist-1]
+ ){
+ rc = sqlite3Fts3SegReaderStep(pFts3, &pCsr->csr);
+ if( rc!=SQLITE_ROW ){
+ pCsr->isEof = 1;
+ return rc;
+ }
+
+ pCsr->iCol = 0;
+ pCsr->iPos = 0;
+ pCsr->iDocid = 0;
+ pCsr->pNext = pCsr->csr.aDoclist;
+
+ /* Read docid */
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &pCsr->iDocid);
+ }
+
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &v);
+ if( v==0 ){
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &v);
+ pCsr->iDocid += v;
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &v);
+ pCsr->iCol = 0;
+ pCsr->iPos = 0;
+ }
+
+ if( v==1 ){
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &v);
+ pCsr->iCol += (int)v;
+ pCsr->iPos = 0;
+ pCsr->pNext += sqlite3Fts3GetVarint(pCsr->pNext, &v);
+ }
+
+ pCsr->iPos += (int)(v - 2);
+
+ return SQLITE_OK;
+}
+
+/*
+** xFilter - Initialize a cursor to point at the start of its data.
+*/
+static int fts3termFilterMethod(
+ sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
+ int idxNum, /* Strategy index */
+ const char *idxStr, /* Unused */
+ int nVal, /* Number of elements in apVal */
+ sqlite3_value **apVal /* Arguments for the indexing scheme */
+){
+ Fts3termCursor *pCsr = (Fts3termCursor *)pCursor;
+ Fts3termTable *p = (Fts3termTable *)pCursor->pVtab;
+ Fts3Table *pFts3 = p->pFts3Tab;
+ int rc;
+
+ UNUSED_PARAMETER(nVal);
+ UNUSED_PARAMETER(idxNum);
+ UNUSED_PARAMETER(idxStr);
+ UNUSED_PARAMETER(apVal);
+
+ assert( idxStr==0 && idxNum==0 );
+
+ /* In case this cursor is being reused, close and zero it. */
+ testcase(pCsr->filter.zTerm);
+ sqlite3Fts3SegReaderFinish(&pCsr->csr);
+ memset(&pCsr->csr, 0, ((u8*)&pCsr[1]) - (u8*)&pCsr->csr);
+
+ pCsr->filter.flags = FTS3_SEGMENT_REQUIRE_POS|FTS3_SEGMENT_IGNORE_EMPTY;
+ pCsr->filter.flags |= FTS3_SEGMENT_SCAN;
+
+ rc = sqlite3Fts3SegReaderCursor(pFts3, 0, p->iIndex, FTS3_SEGCURSOR_ALL,
+ pCsr->filter.zTerm, pCsr->filter.nTerm, 0, 1, &pCsr->csr
+ );
+ if( rc==SQLITE_OK ){
+ rc = sqlite3Fts3SegReaderStart(pFts3, &pCsr->csr, &pCsr->filter);
+ }
+ if( rc==SQLITE_OK ){
+ rc = fts3termNextMethod(pCursor);
+ }
+ return rc;
+}
+
+/*
+** xEof - Return true if the cursor is at EOF, or false otherwise.
+*/
+static int fts3termEofMethod(sqlite3_vtab_cursor *pCursor){
+ Fts3termCursor *pCsr = (Fts3termCursor *)pCursor;
+ return pCsr->isEof;
+}
+
+/*
+** xColumn - Return a column value.
+*/
+static int fts3termColumnMethod(
+ sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
+ sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
+ int iCol /* Index of column to read value from */
+){
+ Fts3termCursor *p = (Fts3termCursor *)pCursor;
+
+ assert( iCol>=0 && iCol<=3 );
+ switch( iCol ){
+ case 0:
+ sqlite3_result_text(pCtx, p->csr.zTerm, p->csr.nTerm, SQLITE_TRANSIENT);
+ break;
+ case 1:
+ sqlite3_result_int64(pCtx, p->iDocid);
+ break;
+ case 2:
+ sqlite3_result_int64(pCtx, p->iCol);
+ break;
+ default:
+ sqlite3_result_int64(pCtx, p->iPos);
+ break;
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** xRowid - Return the current rowid for the cursor.
+*/
+static int fts3termRowidMethod(
+ sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
+ sqlite_int64 *pRowid /* OUT: Rowid value */
+){
+ Fts3termCursor *pCsr = (Fts3termCursor *)pCursor;
+ *pRowid = pCsr->iRowid;
+ return SQLITE_OK;
+}
+
+/*
+** Register the fts3term module with database connection db. Return SQLITE_OK
+** if successful or an error code if sqlite3_create_module() fails.
+*/
+int sqlite3Fts3InitTerm(sqlite3 *db){
+ static const sqlite3_module fts3term_module = {
+ 0, /* iVersion */
+ fts3termConnectMethod, /* xCreate */
+ fts3termConnectMethod, /* xConnect */
+ fts3termBestIndexMethod, /* xBestIndex */
+ fts3termDisconnectMethod, /* xDisconnect */
+ fts3termDisconnectMethod, /* xDestroy */
+ fts3termOpenMethod, /* xOpen */
+ fts3termCloseMethod, /* xClose */
+ fts3termFilterMethod, /* xFilter */
+ fts3termNextMethod, /* xNext */
+ fts3termEofMethod, /* xEof */
+ fts3termColumnMethod, /* xColumn */
+ fts3termRowidMethod, /* xRowid */
+ 0, /* xUpdate */
+ 0, /* xBegin */
+ 0, /* xSync */
+ 0, /* xCommit */
+ 0, /* xRollback */
+ 0, /* xFindFunction */
+ 0, /* xRename */
+ 0, /* xSavepoint */
+ 0, /* xRelease */
+ 0, /* xRollbackTo */
+ 0 /* xShadowName */
+ };
+ int rc; /* Return code */
+
+ rc = sqlite3_create_module(db, "fts4term", &fts3term_module, 0);
+ return rc;
+}
+
+#endif
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
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