| /* |
| ** 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--; |
| } |
| |
| *ppVtab = 0; |
| |
| /* 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); |
| p = (Fts3termTable *)sqlite3Fts3MallocZero(nByte); |
| if( !p ) return SQLITE_NOMEM; |
| |
| p->pFts3Tab = (Fts3Table*)sqlite3Fts3MallocZero( |
| sizeof(Fts3Table) + nDb + nFts3 + 2 |
| ); |
| if( p->pFts3Tab==0 ){ |
| sqlite3_free(p); |
| return SQLITE_NOMEM; |
| } |
| 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(pFts3); |
| 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 */ |
| 0 /* xIntegrity */ |
| }; |
| int rc; /* Return code */ |
| |
| rc = sqlite3_create_module(db, "fts4term", &fts3term_module, 0); |
| return rc; |
| } |
| |
| #endif |
| #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */ |