/*
** 2014 Jun 09
**
** 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 is an SQLite module implementing full-text search.
*/
#include "fts5Int.h"
typedef struct Fts5Table Fts5Table;
typedef struct Fts5Cursor Fts5Cursor;
typedef struct Fts5Global Fts5Global;
typedef struct Fts5Auxiliary Fts5Auxiliary;
typedef struct Fts5Auxdata Fts5Auxdata;
typedef struct Fts5TokenizerModule Fts5TokenizerModule;
/*
** NOTES ON TRANSACTIONS:
**
** SQLite invokes the following virtual table methods as transactions are
** opened and closed by the user:
**
** xBegin(): Start of a new transaction.
** xSync(): Initial part of two-phase commit.
** xCommit(): Final part of two-phase commit.
** xRollback(): Rollback the transaction.
**
** Anything that is required as part of a commit that may fail is performed
** in the xSync() callback. Current versions of SQLite ignore any errors
** returned by xCommit().
**
** And as sub-transactions are opened/closed:
**
** xSavepoint(int S): Open savepoint S.
** xRelease(int S): Commit and close savepoint S.
** xRollbackTo(int S): Rollback to start of savepoint S.
**
** During a write-transaction the fts5_index.c module may cache some data
** in-memory. It is flushed to disk whenever xSync(), xRelease() or
** xSavepoint() is called. And discarded whenever xRollback() or xRollbackTo()
** is called.
**
** Additionally, if SQLITE_DEBUG is defined, an instance of the following
** structure is used to record the current transaction state. This information
** is not required, but it is used in the assert() statements executed by
** function fts5CheckTransactionState() (see below).
*/
struct Fts5TransactionState {
int eState; /* 0==closed, 1==open, 2==synced */
int iSavepoint; /* Number of open savepoints (0 -> none) */
};
/*
** A single object of this type is allocated when the FTS5 module is
** registered with a database handle. It is used to store pointers to
** all registered FTS5 extensions - tokenizers and auxiliary functions.
*/
struct Fts5Global {
fts5_api api; /* User visible part of object (see fts5.h) */
sqlite3 *db; /* Associated database connection */
i64 iNextId; /* Used to allocate unique cursor ids */
Fts5Auxiliary *pAux; /* First in list of all aux. functions */
Fts5TokenizerModule *pTok; /* First in list of all tokenizer modules */
Fts5Cursor *pCsr; /* First in list of all open cursors */
};
/*
** Each auxiliary function registered with the FTS5 module is represented
** by an object of the following type. All such objects are stored as part
** of the Fts5Global.pAux list.
*/
struct Fts5Auxiliary {
Fts5Global *pGlobal; /* Global context for this function */
char *zFunc; /* Function name (nul-terminated) */
void *pUserData; /* User-data pointer */
fts5_extension_function xFunc; /* Callback function */
void (*xDestroy)(void*); /* Destructor function */
Fts5Auxiliary *pNext; /* Next registered auxiliary function */
};
/*
** Each tokenizer module registered with the FTS5 module is represented
** by an object of the following type. All such objects are stored as part
** of the Fts5Global.pTok list.
*/
struct Fts5TokenizerModule {
char *zName; /* Name of tokenizer */
void *pUserData; /* User pointer passed to xCreate() */
fts5_tokenizer x; /* Tokenizer functions */
void (*xDestroy)(void*); /* Destructor function */
Fts5TokenizerModule *pNext; /* Next registered tokenizer module */
};
/*
** Virtual-table object.
*/
struct Fts5Table {
sqlite3_vtab base; /* Base class used by SQLite core */
Fts5Config *pConfig; /* Virtual table configuration */
Fts5Index *pIndex; /* Full-text index */
Fts5Storage *pStorage; /* Document store */
Fts5Global *pGlobal; /* Global (connection wide) data */
Fts5Cursor *pSortCsr; /* Sort data from this cursor */
#ifdef SQLITE_DEBUG
struct Fts5TransactionState ts;
#endif
};
struct Fts5MatchPhrase {
Fts5Buffer *pPoslist; /* Pointer to current poslist */
int nTerm; /* Size of phrase in terms */
};
/*
** pStmt:
** SELECT rowid, <fts> FROM <fts> ORDER BY +rank;
**
** aIdx[]:
** There is one entry in the aIdx[] array for each phrase in the query,
** the value of which is the offset within aPoslist[] following the last
** byte of the position list for the corresponding phrase.
*/
struct Fts5Sorter {
sqlite3_stmt *pStmt;
i64 iRowid; /* Current rowid */
const u8 *aPoslist; /* Position lists for current row */
int nIdx; /* Number of entries in aIdx[] */
int aIdx[0]; /* Offsets into aPoslist for current row */
};
/*
** Virtual-table cursor object.
**
** zSpecial:
** If this is a 'special' query (refer to function fts5SpecialMatch()),
** then this variable points to a nul-terminated buffer containing the
** result to return through the table-name column. It is nul-terminated
** and should eventually be freed using sqlite3_free().
*/
struct Fts5Cursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
int idxNum; /* idxNum passed to xFilter() */
sqlite3_stmt *pStmt; /* Statement used to read %_content */
Fts5Expr *pExpr; /* Expression for MATCH queries */
Fts5Sorter *pSorter; /* Sorter for "ORDER BY rank" queries */
int csrflags; /* Mask of cursor flags (see below) */
Fts5Cursor *pNext; /* Next cursor in Fts5Cursor.pCsr list */
char *zSpecial; /* Result of special query */
/* "rank" function. Populated on demand from vtab.xColumn(). */
Fts5Auxiliary *pRank; /* Rank callback (or NULL) */
int nRankArg; /* Number of trailing arguments for rank() */
sqlite3_value **apRankArg; /* Array of trailing arguments */
sqlite3_stmt *pRankArgStmt; /* Origin of objects in apRankArg[] */
/* Variables used by auxiliary functions */
i64 iCsrId; /* Cursor id */
Fts5Auxiliary *pAux; /* Currently executing extension function */
Fts5Auxdata *pAuxdata; /* First in linked list of saved aux-data */
int *aColumnSize; /* Values for xColumnSize() */
int nInstCount; /* Number of phrase instances */
int *aInst; /* 3 integers per phrase instance */
};
/*
** Values for Fts5Cursor.csrflags
*/
#define FTS5CSR_REQUIRE_CONTENT 0x01
#define FTS5CSR_REQUIRE_DOCSIZE 0x02
#define FTS5CSR_EOF 0x04
/*
** Macros to Set(), Clear() and Test() cursor flags.
*/
#define CsrFlagSet(pCsr, flag) ((pCsr)->csrflags |= (flag))
#define CsrFlagClear(pCsr, flag) ((pCsr)->csrflags &= ~(flag))
#define CsrFlagTest(pCsr, flag) ((pCsr)->csrflags & (flag))
struct Fts5Auxdata {
Fts5Auxiliary *pAux; /* Extension to which this belongs */
void *pPtr; /* Pointer value */
void(*xDelete)(void*); /* Destructor */
Fts5Auxdata *pNext; /* Next object in linked list */
};
#ifdef SQLITE_DEBUG
#define FTS5_BEGIN 1
#define FTS5_SYNC 2
#define FTS5_COMMIT 3
#define FTS5_ROLLBACK 4
#define FTS5_SAVEPOINT 5
#define FTS5_RELEASE 6
#define FTS5_ROLLBACKTO 7
static void fts5CheckTransactionState(Fts5Table *p, int op, int iSavepoint){
switch( op ){
case FTS5_BEGIN:
assert( p->ts.eState==0 );
p->ts.eState = 1;
p->ts.iSavepoint = -1;
break;
case FTS5_SYNC:
assert( p->ts.eState==1 );
p->ts.eState = 2;
break;
case FTS5_COMMIT:
assert( p->ts.eState==2 );
p->ts.eState = 0;
break;
case FTS5_ROLLBACK:
assert( p->ts.eState==1 || p->ts.eState==2 );
p->ts.eState = 0;
break;
case FTS5_SAVEPOINT:
assert( p->ts.eState==1 );
assert( iSavepoint>=0 );
assert( iSavepoint>p->ts.iSavepoint );
p->ts.iSavepoint = iSavepoint;
break;
case FTS5_RELEASE:
assert( p->ts.eState==1 );
assert( iSavepoint>=0 );
assert( iSavepoint<=p->ts.iSavepoint );
p->ts.iSavepoint = iSavepoint-1;
break;
case FTS5_ROLLBACKTO:
assert( p->ts.eState==1 );
assert( iSavepoint>=0 );
assert( iSavepoint<=p->ts.iSavepoint );
p->ts.iSavepoint = iSavepoint;
break;
}
}
#else
# define fts5CheckTransactionState(x,y,z)
#endif
/*
** Close a virtual table handle opened by fts5InitVtab(). If the bDestroy
** argument is non-zero, attempt delete the shadow tables from teh database
*/
static int fts5FreeVtab(Fts5Table *pTab, int bDestroy){
int rc = SQLITE_OK;
if( pTab ){
int rc2;
rc2 = sqlite3Fts5IndexClose(pTab->pIndex, bDestroy);
if( rc==SQLITE_OK ) rc = rc2;
rc2 = sqlite3Fts5StorageClose(pTab->pStorage, bDestroy);
if( rc==SQLITE_OK ) rc = rc2;
sqlite3Fts5ConfigFree(pTab->pConfig);
sqlite3_free(pTab);
}
return rc;
}
/*
** The xDisconnect() virtual table method.
*/
static int fts5DisconnectMethod(sqlite3_vtab *pVtab){
return fts5FreeVtab((Fts5Table*)pVtab, 0);
}
/*
** The xDestroy() virtual table method.
*/
static int fts5DestroyMethod(sqlite3_vtab *pVtab){
return fts5FreeVtab((Fts5Table*)pVtab, 1);
}
/*
** This function is the implementation of both the xConnect and xCreate
** methods of the FTS3 virtual table.
**
** The argv[] array contains the following:
**
** argv[0] -> module name ("fts5")
** argv[1] -> database name
** argv[2] -> table name
** argv[...] -> "column name" and other module argument fields.
*/
static int fts5InitVtab(
int bCreate, /* True for xCreate, false for xConnect */
sqlite3 *db, /* The SQLite database connection */
void *pAux, /* Hash table containing tokenizers */
int argc, /* Number of elements in argv array */
const char * const *argv, /* xCreate/xConnect argument array */
sqlite3_vtab **ppVTab, /* Write the resulting vtab structure here */
char **pzErr /* Write any error message here */
){
Fts5Global *pGlobal = (Fts5Global*)pAux;
const char **azConfig = (const char**)argv;
int rc = SQLITE_OK; /* Return code */
Fts5Config *pConfig; /* Results of parsing argc/argv */
Fts5Table *pTab = 0; /* New virtual table object */
/* Allocate the new vtab object and parse the configuration */
pTab = (Fts5Table*)sqlite3Fts5MallocZero(&rc, sizeof(Fts5Table));
if( rc==SQLITE_OK ){
rc = sqlite3Fts5ConfigParse(pGlobal, db, argc, azConfig, &pConfig, pzErr);
assert( (rc==SQLITE_OK && *pzErr==0) || pConfig==0 );
}
if( rc==SQLITE_OK ){
pTab->pConfig = pConfig;
pTab->pGlobal = pGlobal;
}
/* Open the index sub-system */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5IndexOpen(pConfig, bCreate, &pTab->pIndex, pzErr);
}
/* Open the storage sub-system */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5StorageOpen(
pConfig, pTab->pIndex, bCreate, &pTab->pStorage, pzErr
);
}
/* Call sqlite3_declare_vtab() */
if( rc==SQLITE_OK ){
rc = sqlite3Fts5ConfigDeclareVtab(pConfig);
}
if( rc!=SQLITE_OK ){
fts5FreeVtab(pTab, 0);
pTab = 0;
}else if( bCreate ){
fts5CheckTransactionState(pTab, FTS5_BEGIN, 0);
}
*ppVTab = (sqlite3_vtab*)pTab;
return rc;
}
/*
** The xConnect() and xCreate() methods for the virtual table. All the
** work is done in function fts5InitVtab().
*/
static int fts5ConnectMethod(
sqlite3 *db, /* Database connection */
void *pAux, /* Pointer to tokenizer hash 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 */
){
return fts5InitVtab(0, db, pAux, argc, argv, ppVtab, pzErr);
}
static int fts5CreateMethod(
sqlite3 *db, /* Database connection */
void *pAux, /* Pointer to tokenizer hash 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 */
){
return fts5InitVtab(1, db, pAux, argc, argv, ppVtab, pzErr);
}
/*
** The three query plans xBestIndex may choose between.
*/
#define FTS5_PLAN_SCAN 1 /* No usable constraint */
#define FTS5_PLAN_MATCH 2 /* (<tbl> MATCH ?) */
#define FTS5_PLAN_SORTED_MATCH 3 /* (<tbl> MATCH ? ORDER BY rank) */
#define FTS5_PLAN_ROWID 4 /* (rowid = ?) */
#define FTS5_PLAN_SOURCE 5 /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL 6 /* An internal query */
#define FTS5_PLAN(idxNum) ((idxNum) & 0x7)
#define FTS5_ORDER_DESC 8 /* ORDER BY rowid DESC */
#define FTS5_ORDER_ASC 16 /* ORDER BY rowid ASC */
/*
** Search the object passed as the first argument for a usable constraint
** on column iCol using operator eOp. If one is found, return its index in
** the pInfo->aConstraint[] array. If no such constraint is found, return
** a negative value.
*/
static int fts5FindConstraint(sqlite3_index_info *pInfo, int eOp, int iCol){
int i;
for(i=0; i<pInfo->nConstraint; i++){
struct sqlite3_index_constraint *p = &pInfo->aConstraint[i];
if( p->usable && p->iColumn==iCol && p->op==eOp ) return i;
}
return -1;
}
/*
** Implementation of the xBestIndex method for FTS5 tables. There
** are three possible strategies, in order of preference:
**
** 1. Full-text search using a MATCH operator.
** 2. A by-rowid lookup.
** 3. A full-table scan.
*/
static int fts5BestIndexMethod(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
Fts5Table *pTab = (Fts5Table*)pVTab;
Fts5Config *pConfig = pTab->pConfig;
int iCons;
int ePlan = FTS5_PLAN_SCAN;
iCons = fts5FindConstraint(pInfo,SQLITE_INDEX_CONSTRAINT_MATCH,pConfig->nCol);
if( iCons>=0 ){
ePlan = FTS5_PLAN_MATCH;
pInfo->estimatedCost = 1.0;
}else{
iCons = fts5FindConstraint(pInfo, SQLITE_INDEX_CONSTRAINT_EQ, -1);
if( iCons>=0 ){
ePlan = FTS5_PLAN_ROWID;
pInfo->estimatedCost = 2.0;
}
}
if( iCons>=0 ){
pInfo->aConstraintUsage[iCons].argvIndex = 1;
pInfo->aConstraintUsage[iCons].omit = 1;
}else{
pInfo->estimatedCost = 10000000.0;
}
if( pInfo->nOrderBy==1 ){
int iSort = pInfo->aOrderBy[0].iColumn;
if( iSort<0 ){
/* ORDER BY rowid [ASC|DESC] */
pInfo->orderByConsumed = 1;
}else if( iSort==(pConfig->nCol+1) && ePlan==FTS5_PLAN_MATCH ){
/* ORDER BY rank [ASC|DESC] */
pInfo->orderByConsumed = 1;
ePlan = FTS5_PLAN_SORTED_MATCH;
}
if( pInfo->orderByConsumed ){
ePlan |= pInfo->aOrderBy[0].desc ? FTS5_ORDER_DESC : FTS5_ORDER_ASC;
}
}
pInfo->idxNum = ePlan;
return SQLITE_OK;
}
/*
** Implementation of xOpen method.
*/
static int fts5OpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
Fts5Table *pTab = (Fts5Table*)pVTab;
Fts5Config *pConfig = pTab->pConfig;
Fts5Cursor *pCsr; /* New cursor object */
int nByte; /* Bytes of space to allocate */
int rc = SQLITE_OK; /* Return code */
nByte = sizeof(Fts5Cursor) + pConfig->nCol * sizeof(int);
pCsr = (Fts5Cursor*)sqlite3_malloc(nByte);
if( pCsr ){
Fts5Global *pGlobal = pTab->pGlobal;
memset(pCsr, 0, nByte);
pCsr->aColumnSize = (int*)&pCsr[1];
pCsr->pNext = pGlobal->pCsr;
pGlobal->pCsr = pCsr;
pCsr->iCsrId = ++pGlobal->iNextId;
}else{
rc = SQLITE_NOMEM;
}
*ppCsr = (sqlite3_vtab_cursor*)pCsr;
return rc;
}
static int fts5StmtType(int idxNum){
if( FTS5_PLAN(idxNum)==FTS5_PLAN_SCAN ){
return (idxNum&FTS5_ORDER_ASC) ? FTS5_STMT_SCAN_ASC : FTS5_STMT_SCAN_DESC;
}
return FTS5_STMT_LOOKUP;
}
/*
** This function is called after the cursor passed as the only argument
** is moved to point at a different row. It clears all cached data
** specific to the previous row stored by the cursor object.
*/
static void fts5CsrNewrow(Fts5Cursor *pCsr){
CsrFlagSet(pCsr, FTS5CSR_REQUIRE_CONTENT | FTS5CSR_REQUIRE_DOCSIZE );
sqlite3_free(pCsr->aInst);
pCsr->aInst = 0;
pCsr->nInstCount = 0;
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5CloseMethod(sqlite3_vtab_cursor *pCursor){
Fts5Table *pTab = (Fts5Table*)(pCursor->pVtab);
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
Fts5Cursor **pp;
Fts5Auxdata *pData;
Fts5Auxdata *pNext;
fts5CsrNewrow(pCsr);
if( pCsr->pStmt ){
int eStmt = fts5StmtType(pCsr->idxNum);
sqlite3Fts5StorageStmtRelease(pTab->pStorage, eStmt, pCsr->pStmt);
}
if( pCsr->pSorter ){
Fts5Sorter *pSorter = pCsr->pSorter;
sqlite3_finalize(pSorter->pStmt);
sqlite3_free(pSorter);
}
if( pCsr->idxNum!=FTS5_PLAN_SOURCE ){
sqlite3Fts5ExprFree(pCsr->pExpr);
}
for(pData=pCsr->pAuxdata; pData; pData=pNext){
pNext = pData->pNext;
if( pData->xDelete ) pData->xDelete(pData->pPtr);
sqlite3_free(pData);
}
/* Remove the cursor from the Fts5Global.pCsr list */
for(pp=&pTab->pGlobal->pCsr; (*pp)!=pCsr; pp=&(*pp)->pNext);
*pp = pCsr->pNext;
sqlite3_finalize(pCsr->pRankArgStmt);
sqlite3_free(pCsr->apRankArg);
sqlite3_free(pCsr->zSpecial);
sqlite3_free(pCsr);
return SQLITE_OK;
}
static int fts5SorterNext(Fts5Cursor *pCsr){
Fts5Sorter *pSorter = pCsr->pSorter;
int rc;
rc = sqlite3_step(pSorter->pStmt);
if( rc==SQLITE_DONE ){
rc = SQLITE_OK;
CsrFlagSet(pCsr, FTS5CSR_EOF);
}else if( rc==SQLITE_ROW ){
const u8 *a;
const u8 *aBlob;
int nBlob;
int i;
int iOff = 0;
rc = SQLITE_OK;
pSorter->iRowid = sqlite3_column_int64(pSorter->pStmt, 0);
nBlob = sqlite3_column_bytes(pSorter->pStmt, 1);
aBlob = a = sqlite3_column_blob(pSorter->pStmt, 1);
for(i=0; i<(pSorter->nIdx-1); i++){
int iVal;
a += getVarint32(a, iVal);
iOff += iVal;
pSorter->aIdx[i] = iOff;
}
pSorter->aIdx[i] = &aBlob[nBlob] - a;
pSorter->aPoslist = a;
fts5CsrNewrow(pCsr);
}
return rc;
}
/*
** Advance the cursor to the next row in the table that matches the
** search criteria.
**
** Return SQLITE_OK if nothing goes wrong. SQLITE_OK is returned
** even if we reach end-of-file. The fts5EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts5NextMethod(sqlite3_vtab_cursor *pCursor){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int ePlan = FTS5_PLAN(pCsr->idxNum);
int rc = SQLITE_OK;
switch( ePlan ){
case FTS5_PLAN_MATCH:
case FTS5_PLAN_SOURCE:
rc = sqlite3Fts5ExprNext(pCsr->pExpr);
if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
}
fts5CsrNewrow(pCsr);
break;
case FTS5_PLAN_SPECIAL: {
CsrFlagSet(pCsr, FTS5CSR_EOF);
break;
}
case FTS5_PLAN_SORTED_MATCH: {
rc = fts5SorterNext(pCsr);
break;
}
default:
rc = sqlite3_step(pCsr->pStmt);
if( rc!=SQLITE_ROW ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
rc = sqlite3_reset(pCsr->pStmt);
}else{
rc = SQLITE_OK;
}
break;
}
return rc;
}
static int fts5CursorFirstSorted(Fts5Table *pTab, Fts5Cursor *pCsr, int bAsc){
Fts5Config *pConfig = pTab->pConfig;
Fts5Sorter *pSorter;
int nPhrase;
int nByte;
int rc = SQLITE_OK;
char *zSql;
const char *zRank = pConfig->zRank ? pConfig->zRank : FTS5_DEFAULT_RANK;
nPhrase = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
nByte = sizeof(Fts5Sorter) + sizeof(int) * nPhrase;
pSorter = (Fts5Sorter*)sqlite3_malloc(nByte);
if( pSorter==0 ) return SQLITE_NOMEM;
memset(pSorter, 0, nByte);
pSorter->nIdx = nPhrase;
/* TODO: It would be better to have some system for reusing statement
** handles here, rather than preparing a new one for each query. But that
** is not possible as SQLite reference counts the virtual table objects.
** And since the statement required here reads from this very virtual
** table, saving it creates a circular reference.
**
** If SQLite a built-in statement cache, this wouldn't be a problem. */
zSql = sqlite3_mprintf("SELECT rowid, rank FROM %Q.%Q ORDER BY %s(%s%s%s) %s",
pConfig->zDb, pConfig->zName, zRank, pConfig->zName,
(pConfig->zRankArgs ? ", " : ""),
(pConfig->zRankArgs ? pConfig->zRankArgs : ""),
bAsc ? "ASC" : "DESC"
);
if( zSql==0 ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_prepare_v2(pConfig->db, zSql, -1, &pSorter->pStmt, 0);
sqlite3_free(zSql);
}
pCsr->pSorter = pSorter;
if( rc==SQLITE_OK ){
assert( pTab->pSortCsr==0 );
pTab->pSortCsr = pCsr;
rc = fts5SorterNext(pCsr);
pTab->pSortCsr = 0;
}
if( rc!=SQLITE_OK ){
sqlite3_finalize(pSorter->pStmt);
sqlite3_free(pSorter);
pCsr->pSorter = 0;
}
return rc;
}
static int fts5CursorFirst(Fts5Table *pTab, Fts5Cursor *pCsr, int bAsc){
int rc;
rc = sqlite3Fts5ExprFirst(pCsr->pExpr, pTab->pIndex, bAsc);
if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
}
fts5CsrNewrow(pCsr);
return rc;
}
/*
** Process a "special" query. A special query is identified as one with a
** MATCH expression that begins with a '*' character. The remainder of
** the text passed to the MATCH operator are used as the special query
** parameters.
*/
static int fts5SpecialMatch(
Fts5Table *pTab,
Fts5Cursor *pCsr,
const char *zQuery
){
int rc = SQLITE_OK; /* Return code */
const char *z = zQuery; /* Special query text */
int n; /* Number of bytes in text at z */
while( z[0]==' ' ) z++;
for(n=0; z[n] && z[n]!=' '; n++);
assert( pTab->base.zErrMsg==0 );
assert( pCsr->zSpecial==0 );
if( 0==sqlite3_strnicmp("reads", z, n) ){
pCsr->zSpecial = sqlite3_mprintf("%d", sqlite3Fts5IndexReads(pTab->pIndex));
pCsr->idxNum = FTS5_PLAN_SPECIAL;
if( pCsr->zSpecial==0 ) rc = SQLITE_NOMEM;
}
else{
/* An unrecognized directive. Return an error message. */
pTab->base.zErrMsg = sqlite3_mprintf("unknown special query: %.*s", n, z);
rc = SQLITE_ERROR;
}
return rc;
}
/*
** Search for an auxiliary function named zName that can be used with table
** pTab. If one is found, return a pointer to the corresponding Fts5Auxiliary
** structure. Otherwise, if no such function exists, return NULL.
*/
static Fts5Auxiliary *fts5FindAuxiliary(Fts5Table *pTab, const char *zName){
Fts5Auxiliary *pAux;
for(pAux=pTab->pGlobal->pAux; pAux; pAux=pAux->pNext){
if( sqlite3_stricmp(zName, pAux->zFunc)==0 ) return pAux;
}
/* No function of the specified name was found. Return 0. */
return 0;
}
static int fts5FindRankFunction(Fts5Cursor *pCsr){
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
Fts5Config *pConfig = pTab->pConfig;
const char *zRank = pConfig->zRank;
int rc = SQLITE_OK;
Fts5Auxiliary *pAux;
if( zRank==0 ) zRank = FTS5_DEFAULT_RANK;
if( pTab->pConfig->zRankArgs ){
char *zSql = sqlite3_mprintf("SELECT %s", pTab->pConfig->zRankArgs);
if( zSql==0 ){
rc = SQLITE_NOMEM;
}else{
sqlite3_stmt *pStmt = 0;
rc = sqlite3_prepare_v2(pConfig->db, zSql, -1, &pStmt, 0);
sqlite3_free(zSql);
assert( rc==SQLITE_OK || pCsr->pRankArgStmt==0 );
if( rc==SQLITE_OK ){
if( SQLITE_ROW==sqlite3_step(pStmt) ){
int nByte;
pCsr->nRankArg = sqlite3_column_count(pStmt);
nByte = sizeof(sqlite3_value*)*pCsr->nRankArg;
pCsr->apRankArg = (sqlite3_value**)sqlite3Fts5MallocZero(&rc, nByte);
if( rc==SQLITE_OK ){
int i;
for(i=0; i<pCsr->nRankArg; i++){
pCsr->apRankArg[i] = sqlite3_column_value(pStmt, i);
}
}
pCsr->pRankArgStmt = pStmt;
}else{
rc = sqlite3_finalize(pStmt);
assert( rc!=SQLITE_OK );
}
}
}
}
if( rc==SQLITE_OK ){
pAux = fts5FindAuxiliary(pTab, zRank);
if( pAux==0 ){
assert( pTab->base.zErrMsg==0 );
pTab->base.zErrMsg = sqlite3_mprintf("no such function: %s", zRank);
rc = SQLITE_ERROR;
}
}
pCsr->pRank = pAux;
return rc;
}
/*
** This is the xFilter interface for the virtual table. See
** the virtual table xFilter method documentation for additional
** information.
*/
static int fts5FilterMethod(
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 */
){
Fts5Table *pTab = (Fts5Table*)(pCursor->pVtab);
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int bAsc = ((idxNum & FTS5_ORDER_ASC) ? 1 : 0);
int rc = SQLITE_OK;
assert( pCsr->pStmt==0 );
assert( pCsr->pExpr==0 );
assert( pCsr->csrflags==0 );
assert( pCsr->pRank==0 );
if( pTab->pSortCsr ){
/* If pSortCsr is non-NULL, then this call is being made as part of
** processing for a "... MATCH <expr> ORDER BY rank" query (ePlan is
** set to FTS5_PLAN_SORTED_MATCH). pSortCsr is the cursor that will
** return results to the user for this query. The current cursor
** (pCursor) is used to execute the query issued by function
** fts5CursorFirstSorted() above. */
assert( FTS5_PLAN(idxNum)==FTS5_PLAN_SCAN );
pCsr->idxNum = FTS5_PLAN_SOURCE;
pCsr->pExpr = pTab->pSortCsr->pExpr;
rc = fts5CursorFirst(pTab, pCsr, bAsc);
}else{
int ePlan = FTS5_PLAN(idxNum);
pCsr->idxNum = idxNum;
if( ePlan==FTS5_PLAN_MATCH || ePlan==FTS5_PLAN_SORTED_MATCH ){
const char *zExpr = (const char*)sqlite3_value_text(apVal[0]);
if( zExpr[0]=='*' ){
/* The user has issued a query of the form "MATCH '*...'". This
** indicates that the MATCH expression is not a full text query,
** but a request for an internal parameter. */
rc = fts5SpecialMatch(pTab, pCsr, &zExpr[1]);
}else{
char **pzErr = &pTab->base.zErrMsg;
rc = sqlite3Fts5ExprNew(pTab->pConfig, zExpr, &pCsr->pExpr, pzErr);
if( rc==SQLITE_OK ){
if( ePlan==FTS5_PLAN_MATCH ){
rc = fts5CursorFirst(pTab, pCsr, bAsc);
}else{
rc = fts5CursorFirstSorted(pTab, pCsr, bAsc);
}
}
}
}else{
/* This is either a full-table scan (ePlan==FTS5_PLAN_SCAN) or a lookup
** by rowid (ePlan==FTS5_PLAN_ROWID). */
int eStmt = fts5StmtType(idxNum);
rc = sqlite3Fts5StorageStmt(pTab->pStorage, eStmt, &pCsr->pStmt);
if( rc==SQLITE_OK ){
if( ePlan==FTS5_PLAN_ROWID ){
sqlite3_bind_value(pCsr->pStmt, 1, apVal[0]);
}
rc = fts5NextMethod(pCursor);
}
}
}
return rc;
}
/*
** This is the xEof method of the virtual table. SQLite calls this
** routine to find out if it has reached the end of a result set.
*/
static int fts5EofMethod(sqlite3_vtab_cursor *pCursor){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
return (CsrFlagTest(pCsr, FTS5CSR_EOF) ? 1 : 0);
}
/*
** Return the rowid that the cursor currently points to.
*/
static i64 fts5CursorRowid(Fts5Cursor *pCsr){
assert( FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_MATCH
|| FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_SORTED_MATCH
|| FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_SOURCE
);
if( pCsr->pSorter ){
return pCsr->pSorter->iRowid;
}else{
return sqlite3Fts5ExprRowid(pCsr->pExpr);
}
}
/*
** This is the xRowid method. The SQLite core calls this routine to
** retrieve the rowid for the current row of the result set. fts5
** exposes %_content.docid as the rowid for the virtual table. The
** rowid should be written to *pRowid.
*/
static int fts5RowidMethod(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int ePlan = FTS5_PLAN(pCsr->idxNum);
assert( CsrFlagTest(pCsr, FTS5CSR_EOF)==0 );
switch( ePlan ){
case FTS5_PLAN_SPECIAL:
*pRowid = 0;
break;
case FTS5_PLAN_SOURCE:
case FTS5_PLAN_MATCH:
case FTS5_PLAN_SORTED_MATCH:
*pRowid = fts5CursorRowid(pCsr);
break;
default:
*pRowid = sqlite3_column_int64(pCsr->pStmt, 0);
break;
}
return SQLITE_OK;
}
/*
** If the cursor requires seeking (bSeekRequired flag is set), seek it.
** Return SQLITE_OK if no error occurs, or an SQLite error code otherwise.
*/
static int fts5SeekCursor(Fts5Cursor *pCsr){
int rc = SQLITE_OK;
/* If the cursor does not yet have a statement handle, obtain one now. */
if( pCsr->pStmt==0 ){
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
int eStmt = fts5StmtType(pCsr->idxNum);
rc = sqlite3Fts5StorageStmt(pTab->pStorage, eStmt, &pCsr->pStmt);
assert( CsrFlagTest(pCsr, FTS5CSR_REQUIRE_CONTENT) );
}
if( rc==SQLITE_OK && CsrFlagTest(pCsr, FTS5CSR_REQUIRE_CONTENT) ){
assert( pCsr->pExpr );
sqlite3_reset(pCsr->pStmt);
sqlite3_bind_int64(pCsr->pStmt, 1, fts5CursorRowid(pCsr));
rc = sqlite3_step(pCsr->pStmt);
if( rc==SQLITE_ROW ){
rc = SQLITE_OK;
CsrFlagClear(pCsr, FTS5CSR_REQUIRE_CONTENT);
}else{
rc = sqlite3_reset(pCsr->pStmt);
if( rc==SQLITE_OK ){
rc = SQLITE_CORRUPT_VTAB;
}
}
}
return rc;
}
/*
** This function is called to handle an FTS INSERT command. In other words,
** an INSERT statement of the form:
**
** INSERT INTO fts(fts) VALUES($pCmd)
** INSERT INTO fts(fts, rank) VALUES($pCmd, $pVal)
**
** Argument pVal is the value assigned to column "fts" by the INSERT
** statement. This function returns SQLITE_OK if successful, or an SQLite
** error code if an error occurs.
**
** The commands implemented by this function are documented in the "Special
** INSERT Directives" section of the documentation. It should be updated if
** more commands are added to this function.
*/
static int fts5SpecialInsert(
Fts5Table *pTab, /* Fts5 table object */
sqlite3_value *pCmd, /* Value inserted into special column */
sqlite3_value *pVal /* Value inserted into rowid column */
){
const char *z = (const char*)sqlite3_value_text(pCmd);
int rc = SQLITE_OK;
int bError = 0;
if( 0==sqlite3_stricmp("integrity-check", z) ){
rc = sqlite3Fts5StorageIntegrity(pTab->pStorage);
}else{
rc = sqlite3Fts5ConfigSetValue(pTab->pConfig, z, pVal, &bError);
if( rc==SQLITE_OK ){
if( bError ){
rc = SQLITE_ERROR;
}else{
rc = sqlite3Fts5StorageConfigValue(pTab->pStorage, z, pVal);
}
}
}
return rc;
}
/*
** This function is the implementation of the xUpdate callback used by
** FTS3 virtual tables. It is invoked by SQLite each time a row is to be
** inserted, updated or deleted.
*/
static int fts5UpdateMethod(
sqlite3_vtab *pVtab, /* Virtual table handle */
int nArg, /* Size of argument array */
sqlite3_value **apVal, /* Array of arguments */
sqlite_int64 *pRowid /* OUT: The affected (or effected) rowid */
){
Fts5Table *pTab = (Fts5Table*)pVtab;
Fts5Config *pConfig = pTab->pConfig;
int eType0; /* value_type() of apVal[0] */
int eConflict; /* ON CONFLICT for this DML */
int rc = SQLITE_OK; /* Return code */
/* A transaction must be open when this is called. */
assert( pTab->ts.eState==1 );
/* A delete specifies a single argument - the rowid of the row to remove.
** Update and insert operations pass:
**
** 1. The "old" rowid, or NULL.
** 2. The "new" rowid.
** 3. Values for each of the nCol matchable columns.
** 4. Values for the two hidden columns (<tablename> and "rank").
*/
assert( nArg==1 || nArg==(2 + pConfig->nCol + 2) );
if( nArg>1 && SQLITE_NULL!=sqlite3_value_type(apVal[2 + pConfig->nCol]) ){
return fts5SpecialInsert(pTab,
apVal[2 + pConfig->nCol], apVal[2 + pConfig->nCol + 1]
);
}
eType0 = sqlite3_value_type(apVal[0]);
eConflict = sqlite3_vtab_on_conflict(pConfig->db);
assert( eType0==SQLITE_INTEGER || eType0==SQLITE_NULL );
if( eType0==SQLITE_INTEGER ){
i64 iDel = sqlite3_value_int64(apVal[0]); /* Rowid to delete */
rc = sqlite3Fts5StorageDelete(pTab->pStorage, iDel);
}
if( rc==SQLITE_OK && nArg>1 ){
rc = sqlite3Fts5StorageInsert(pTab->pStorage, apVal, eConflict, pRowid);
}
return rc;
}
/*
** Implementation of xSync() method.
*/
static int fts5SyncMethod(sqlite3_vtab *pVtab){
int rc;
Fts5Table *pTab = (Fts5Table*)pVtab;
fts5CheckTransactionState(pTab, FTS5_SYNC, 0);
rc = sqlite3Fts5StorageSync(pTab->pStorage, 1);
return rc;
}
/*
** Implementation of xBegin() method.
*/
static int fts5BeginMethod(sqlite3_vtab *pVtab){
fts5CheckTransactionState((Fts5Table*)pVtab, FTS5_BEGIN, 0);
return SQLITE_OK;
}
/*
** Implementation of xCommit() method. This is a no-op. The contents of
** the pending-terms hash-table have already been flushed into the database
** by fts5SyncMethod().
*/
static int fts5CommitMethod(sqlite3_vtab *pVtab){
fts5CheckTransactionState((Fts5Table*)pVtab, FTS5_COMMIT, 0);
return SQLITE_OK;
}
/*
** Implementation of xRollback(). Discard the contents of the pending-terms
** hash-table. Any changes made to the database are reverted by SQLite.
*/
static int fts5RollbackMethod(sqlite3_vtab *pVtab){
int rc;
Fts5Table *pTab = (Fts5Table*)pVtab;
fts5CheckTransactionState(pTab, FTS5_ROLLBACK, 0);
rc = sqlite3Fts5StorageRollback(pTab->pStorage);
return rc;
}
static void *fts5ApiUserData(Fts5Context *pCtx){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
return pCsr->pAux->pUserData;
}
static int fts5ApiColumnCount(Fts5Context *pCtx){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
return ((Fts5Table*)(pCsr->base.pVtab))->pConfig->nCol;
}
static int fts5ApiColumnTotalSize(
Fts5Context *pCtx,
int iCol,
sqlite3_int64 *pnToken
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
return sqlite3Fts5StorageSize(pTab->pStorage, iCol, pnToken);
}
static int fts5ApiRowCount(Fts5Context *pCtx, i64 *pnRow){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
return sqlite3Fts5StorageRowCount(pTab->pStorage, pnRow);
}
static int fts5ApiTokenize(
Fts5Context *pCtx,
const char *pText, int nText,
void *pUserData,
int (*xToken)(void*, const char*, int, int, int, int)
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
return sqlite3Fts5Tokenize(pTab->pConfig, pText, nText, pUserData, xToken);
}
static int fts5ApiPhraseCount(Fts5Context *pCtx){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
return sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
}
static int fts5ApiPhraseSize(Fts5Context *pCtx, int iPhrase){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
return sqlite3Fts5ExprPhraseSize(pCsr->pExpr, iPhrase);
}
static int fts5CsrPoslist(Fts5Cursor *pCsr, int iPhrase, const u8 **pa){
int n;
if( pCsr->pSorter ){
Fts5Sorter *pSorter = pCsr->pSorter;
int i1 = (iPhrase==0 ? 0 : pSorter->aIdx[iPhrase-1]);
n = pSorter->aIdx[iPhrase] - i1;
*pa = &pSorter->aPoslist[i1];
}else{
n = sqlite3Fts5ExprPoslist(pCsr->pExpr, iPhrase, pa);
}
return n;
}
/*
** Ensure that the Fts5Cursor.nInstCount and aInst[] variables are populated
** correctly for the current view. Return SQLITE_OK if successful, or an
** SQLite error code otherwise.
*/
static int fts5CacheInstArray(Fts5Cursor *pCsr){
int rc = SQLITE_OK;
if( pCsr->aInst==0 ){
Fts5PoslistReader *aIter; /* One iterator for each phrase */
int nIter; /* Number of iterators/phrases */
int nByte;
nIter = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
nByte = sizeof(Fts5PoslistReader) * nIter;
aIter = (Fts5PoslistReader*)sqlite3Fts5MallocZero(&rc, nByte);
if( aIter ){
Fts5Buffer buf = {0, 0, 0}; /* Build up aInst[] here */
int nInst = 0; /* Number instances seen so far */
int i;
/* Initialize all iterators */
for(i=0; i<nIter; i++){
const u8 *a;
int n = fts5CsrPoslist(pCsr, i, &a);
sqlite3Fts5PoslistReaderInit(-1, a, n, &aIter[i]);
}
while( 1 ){
int *aInst;
int iBest = -1;
for(i=0; i<nIter; i++){
if( (aIter[i].bEof==0)
&& (iBest<0 || aIter[i].iPos<aIter[iBest].iPos)
){
iBest = i;
}
}
if( iBest<0 ) break;
nInst++;
if( sqlite3Fts5BufferGrow(&rc, &buf, nInst * sizeof(int) * 3) ) break;
aInst = &((int*)buf.p)[3 * (nInst-1)];
aInst[0] = iBest;
aInst[1] = FTS5_POS2COLUMN(aIter[iBest].iPos);
aInst[2] = FTS5_POS2OFFSET(aIter[iBest].iPos);
sqlite3Fts5PoslistReaderNext(&aIter[iBest]);
}
pCsr->aInst = (int*)buf.p;
pCsr->nInstCount = nInst;
sqlite3_free(aIter);
}
}
return rc;
}
static int fts5ApiInstCount(Fts5Context *pCtx, int *pnInst){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
int rc;
if( SQLITE_OK==(rc = fts5CacheInstArray(pCsr)) ){
*pnInst = pCsr->nInstCount;
}
return rc;
}
static int fts5ApiInst(
Fts5Context *pCtx,
int iIdx,
int *piPhrase,
int *piCol,
int *piOff
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
int rc;
if( SQLITE_OK==(rc = fts5CacheInstArray(pCsr)) ){
if( iIdx<0 || iIdx>=pCsr->nInstCount ){
rc = SQLITE_RANGE;
}else{
*piPhrase = pCsr->aInst[iIdx*3];
*piCol = pCsr->aInst[iIdx*3 + 1];
*piOff = pCsr->aInst[iIdx*3 + 2];
}
}
return rc;
}
static sqlite3_int64 fts5ApiRowid(Fts5Context *pCtx){
return fts5CursorRowid((Fts5Cursor*)pCtx);
}
static int fts5ApiColumnText(
Fts5Context *pCtx,
int iCol,
const char **pz,
int *pn
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
int rc = fts5SeekCursor(pCsr);
if( rc==SQLITE_OK ){
*pz = (const char*)sqlite3_column_text(pCsr->pStmt, iCol+1);
*pn = sqlite3_column_bytes(pCsr->pStmt, iCol+1);
}
return rc;
}
static int fts5ApiColumnSize(Fts5Context *pCtx, int iCol, int *pnToken){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
int rc = SQLITE_OK;
if( CsrFlagTest(pCsr, FTS5CSR_REQUIRE_DOCSIZE) ){
i64 iRowid = fts5CursorRowid(pCsr);
rc = sqlite3Fts5StorageDocsize(pTab->pStorage, iRowid, pCsr->aColumnSize);
}
if( iCol>=0 && iCol<pTab->pConfig->nCol ){
*pnToken = pCsr->aColumnSize[iCol];
}else{
*pnToken = 0;
}
return rc;
}
static int fts5ApiPoslist(
Fts5Context *pCtx,
int iPhrase,
int *pi,
i64 *piPos
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
const u8 *a; int n; /* Poslist for phrase iPhrase */
n = fts5CsrPoslist(pCsr, iPhrase, &a);
return sqlite3Fts5PoslistNext64(a, n, pi, piPos);
}
static int fts5ApiSetAuxdata(
Fts5Context *pCtx, /* Fts5 context */
void *pPtr, /* Pointer to save as auxdata */
void(*xDelete)(void*) /* Destructor for pPtr (or NULL) */
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Auxdata *pData;
for(pData=pCsr->pAuxdata; pData; pData=pData->pNext){
if( pData->pAux==pCsr->pAux ) break;
}
if( pData ){
if( pData->xDelete ){
pData->xDelete(pData->pPtr);
}
}else{
pData = (Fts5Auxdata*)sqlite3_malloc(sizeof(Fts5Auxdata));
if( pData==0 ) return SQLITE_NOMEM;
memset(pData, 0, sizeof(Fts5Auxdata));
pData->pAux = pCsr->pAux;
pData->pNext = pCsr->pAuxdata;
pCsr->pAuxdata = pData;
}
pData->xDelete = xDelete;
pData->pPtr = pPtr;
return SQLITE_OK;
}
static void *fts5ApiGetAuxdata(Fts5Context *pCtx, int bClear){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Auxdata *pData;
void *pRet = 0;
for(pData=pCsr->pAuxdata; pData; pData=pData->pNext){
if( pData->pAux==pCsr->pAux ) break;
}
if( pData ){
pRet = pData->pPtr;
if( bClear ){
pData->pPtr = 0;
pData->xDelete = 0;
}
}
return pRet;
}
static int fts5ApiQueryPhrase(Fts5Context*, int, void*,
int(*)(const Fts5ExtensionApi*, Fts5Context*, void*)
);
static const Fts5ExtensionApi sFts5Api = {
1, /* iVersion */
fts5ApiUserData,
fts5ApiColumnCount,
fts5ApiRowCount,
fts5ApiColumnTotalSize,
fts5ApiTokenize,
fts5ApiPhraseCount,
fts5ApiPhraseSize,
fts5ApiInstCount,
fts5ApiInst,
fts5ApiRowid,
fts5ApiColumnText,
fts5ApiColumnSize,
fts5ApiPoslist,
fts5ApiQueryPhrase,
fts5ApiSetAuxdata,
fts5ApiGetAuxdata,
};
/*
** Implementation of API function xQueryPhrase().
*/
static int fts5ApiQueryPhrase(
Fts5Context *pCtx,
int iPhrase,
void *pUserData,
int(*xCallback)(const Fts5ExtensionApi*, Fts5Context*, void*)
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Table *pTab = (Fts5Table*)(pCsr->base.pVtab);
int rc;
Fts5Cursor *pNew = 0;
rc = fts5OpenMethod(pCsr->base.pVtab, (sqlite3_vtab_cursor**)&pNew);
if( rc==SQLITE_OK ){
Fts5Config *pConf = pTab->pConfig;
pNew->idxNum = FTS5_PLAN_MATCH;
pNew->base.pVtab = (sqlite3_vtab*)pTab;
rc = sqlite3Fts5ExprPhraseExpr(pConf, pCsr->pExpr, iPhrase, &pNew->pExpr);
}
if( rc==SQLITE_OK ){
for(rc = fts5CursorFirst(pTab, pNew, 0);
rc==SQLITE_OK && CsrFlagTest(pNew, FTS5CSR_EOF)==0;
rc = fts5NextMethod((sqlite3_vtab_cursor*)pNew)
){
rc = xCallback(&sFts5Api, (Fts5Context*)pNew, pUserData);
if( rc!=SQLITE_OK ){
if( rc==SQLITE_DONE ) rc = SQLITE_OK;
break;
}
}
}
fts5CloseMethod((sqlite3_vtab_cursor*)pNew);
return rc;
}
static void fts5ApiInvoke(
Fts5Auxiliary *pAux,
Fts5Cursor *pCsr,
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
assert( pCsr->pAux==0 );
pCsr->pAux = pAux;
pAux->xFunc(&sFts5Api, (Fts5Context*)pCsr, context, argc, argv);
pCsr->pAux = 0;
}
static void fts5ApiCallback(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
Fts5Auxiliary *pAux;
Fts5Cursor *pCsr;
i64 iCsrId;
assert( argc>=1 );
pAux = (Fts5Auxiliary*)sqlite3_user_data(context);
iCsrId = sqlite3_value_int64(argv[0]);
for(pCsr=pAux->pGlobal->pCsr; pCsr; pCsr=pCsr->pNext){
if( pCsr->iCsrId==iCsrId ) break;
}
if( pCsr==0 ){
char *zErr = sqlite3_mprintf("no such cursor: %lld", iCsrId);
sqlite3_result_error(context, zErr, -1);
}else{
fts5ApiInvoke(pAux, pCsr, context, argc-1, &argv[1]);
}
}
/*
** Return a "position-list blob" corresponding to the current position of
** cursor pCsr via sqlite3_result_blob(). A position-list blob contains
** the current position-list for each phrase in the query associated with
** cursor pCsr.
**
** A position-list blob begins with (nPhrase-1) varints, where nPhrase is
** the number of phrases in the query. Following the varints are the
** concatenated position lists for each phrase, in order.
**
** The first varint (if it exists) contains the size of the position list
** for phrase 0. The second (same disclaimer) contains the size of position
** list 1. And so on. There is no size field for the final position list,
** as it can be derived from the total size of the blob.
*/
static int fts5PoslistBlob(sqlite3_context *pCtx, Fts5Cursor *pCsr){
int i;
int rc = SQLITE_OK;
int nPhrase = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
Fts5Buffer val;
memset(&val, 0, sizeof(Fts5Buffer));
/* Append the varints */
for(i=0; i<(nPhrase-1); i++){
const u8 *dummy;
int nByte = sqlite3Fts5ExprPoslist(pCsr->pExpr, i, &dummy);
sqlite3Fts5BufferAppendVarint(&rc, &val, nByte);
}
/* Append the position lists */
for(i=0; i<nPhrase; i++){
const u8 *pPoslist;
int nPoslist;
nPoslist = sqlite3Fts5ExprPoslist(pCsr->pExpr, i, &pPoslist);
sqlite3Fts5BufferAppendBlob(&rc, &val, nPoslist, pPoslist);
}
sqlite3_result_blob(pCtx, val.p, val.n, sqlite3_free);
return rc;
}
/*
** This is the xColumn method, called by SQLite to request a value from
** the row that the supplied cursor currently points to.
*/
static int fts5ColumnMethod(
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 */
){
Fts5Config *pConfig = ((Fts5Table*)(pCursor->pVtab))->pConfig;
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int rc = SQLITE_OK;
assert( CsrFlagTest(pCsr, FTS5CSR_EOF)==0 );
if( pCsr->idxNum==FTS5_PLAN_SPECIAL ){
if( iCol==pConfig->nCol ){
sqlite3_result_text(pCtx, pCsr->zSpecial, -1, SQLITE_TRANSIENT);
}
}else
if( iCol==pConfig->nCol ){
/* User is requesting the value of the special column with the same name
** as the table. Return the cursor integer id number. This value is only
** useful in that it may be passed as the first argument to an FTS5
** auxiliary function. */
sqlite3_result_int64(pCtx, pCsr->iCsrId);
}else if( iCol==pConfig->nCol+1 ){
/* The value of the "rank" column. */
if( FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_SOURCE ){
fts5PoslistBlob(pCtx, pCsr);
}else if(
FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_MATCH
|| FTS5_PLAN(pCsr->idxNum)==FTS5_PLAN_SORTED_MATCH
){
if( pCsr->pRank || SQLITE_OK==(rc = fts5FindRankFunction(pCsr)) ){
fts5ApiInvoke(pCsr->pRank, pCsr, pCtx, pCsr->nRankArg, pCsr->apRankArg);
}
}
}else{
rc = fts5SeekCursor(pCsr);
if( rc==SQLITE_OK ){
sqlite3_result_value(pCtx, sqlite3_column_value(pCsr->pStmt, iCol+1));
}
}
return rc;
}
/*
** This routine implements the xFindFunction method for the FTS3
** virtual table.
*/
static int fts5FindFunctionMethod(
sqlite3_vtab *pVtab, /* Virtual table handle */
int nArg, /* Number of SQL function arguments */
const char *zName, /* Name of SQL function */
void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), /* OUT: Result */
void **ppArg /* OUT: User data for *pxFunc */
){
Fts5Table *pTab = (Fts5Table*)pVtab;
Fts5Auxiliary *pAux;
pAux = fts5FindAuxiliary(pTab, zName);
if( pAux ){
*pxFunc = fts5ApiCallback;
*ppArg = (void*)pAux;
return 1;
}
/* No function of the specified name was found. Return 0. */
return 0;
}
/*
** Implementation of FTS3 xRename method. Rename an fts5 table.
*/
static int fts5RenameMethod(
sqlite3_vtab *pVtab, /* Virtual table handle */
const char *zName /* New name of table */
){
int rc = SQLITE_OK;
return rc;
}
/*
** The xSavepoint() method.
**
** Flush the contents of the pending-terms table to disk.
*/
static int fts5SavepointMethod(sqlite3_vtab *pVtab, int iSavepoint){
Fts5Table *pTab = (Fts5Table*)pVtab;
fts5CheckTransactionState(pTab, FTS5_SAVEPOINT, iSavepoint);
return sqlite3Fts5StorageSync(pTab->pStorage, 0);
}
/*
** The xRelease() method.
**
** This is a no-op.
*/
static int fts5ReleaseMethod(sqlite3_vtab *pVtab, int iSavepoint){
Fts5Table *pTab = (Fts5Table*)pVtab;
fts5CheckTransactionState(pTab, FTS5_RELEASE, iSavepoint);
return sqlite3Fts5StorageSync(pTab->pStorage, 0);
}
/*
** The xRollbackTo() method.
**
** Discard the contents of the pending terms table.
*/
static int fts5RollbackToMethod(sqlite3_vtab *pVtab, int iSavepoint){
Fts5Table *pTab = (Fts5Table*)pVtab;
fts5CheckTransactionState(pTab, FTS5_ROLLBACKTO, iSavepoint);
return sqlite3Fts5StorageRollback(pTab->pStorage);
}
/*
** Register a new auxiliary function with global context pGlobal.
*/
static int fts5CreateAux(
fts5_api *pApi, /* Global context (one per db handle) */
const char *zName, /* Name of new function */
void *pUserData, /* User data for aux. function */
fts5_extension_function xFunc, /* Aux. function implementation */
void(*xDestroy)(void*) /* Destructor for pUserData */
){
Fts5Global *pGlobal = (Fts5Global*)pApi;
int rc = sqlite3_overload_function(pGlobal->db, zName, -1);
if( rc==SQLITE_OK ){
Fts5Auxiliary *pAux;
int nByte; /* Bytes of space to allocate */
nByte = sizeof(Fts5Auxiliary) + strlen(zName) + 1;
pAux = (Fts5Auxiliary*)sqlite3_malloc(nByte);
if( pAux ){
memset(pAux, 0, nByte);
pAux->zFunc = (char*)&pAux[1];
strcpy(pAux->zFunc, zName);
pAux->pGlobal = pGlobal;
pAux->pUserData = pUserData;
pAux->xFunc = xFunc;
pAux->xDestroy = xDestroy;
pAux->pNext = pGlobal->pAux;
pGlobal->pAux = pAux;
}else{
rc = SQLITE_NOMEM;
}
}
return rc;
}
/*
** Register a new tokenizer. This is the implementation of the
** fts5_api.xCreateTokenizer() method.
*/
static int fts5CreateTokenizer(
fts5_api *pApi, /* Global context (one per db handle) */
const char *zName, /* Name of new function */
void *pUserData, /* User data for aux. function */
fts5_tokenizer *pTokenizer, /* Tokenizer implementation */
void(*xDestroy)(void*) /* Destructor for pUserData */
){
Fts5Global *pGlobal = (Fts5Global*)pApi;
Fts5TokenizerModule *pNew;
int nByte; /* Bytes of space to allocate */
int rc = SQLITE_OK;
nByte = sizeof(Fts5TokenizerModule) + strlen(zName) + 1;
pNew = (Fts5TokenizerModule*)sqlite3_malloc(nByte);
if( pNew ){
memset(pNew, 0, nByte);
pNew->zName = (char*)&pNew[1];
strcpy(pNew->zName, zName);
pNew->pUserData = pUserData;
pNew->x = *pTokenizer;
pNew->xDestroy = xDestroy;
pNew->pNext = pGlobal->pTok;
pGlobal->pTok = pNew;
}else{
rc = SQLITE_NOMEM;
}
return rc;
}
/*
** Find a tokenizer. This is the implementation of the
** fts5_api.xFindTokenizer() method.
*/
static int fts5FindTokenizer(
fts5_api *pApi, /* Global context (one per db handle) */
const char *zName, /* Name of new function */
fts5_tokenizer *pTokenizer /* Populate this object */
){
Fts5Global *pGlobal = (Fts5Global*)pApi;
int rc = SQLITE_OK;
Fts5TokenizerModule *pTok;
for(pTok=pGlobal->pTok; pTok; pTok=pTok->pNext){
if( sqlite3_stricmp(zName, pTok->zName)==0 ) break;
}
if( pTok ){
*pTokenizer = pTok->x;
}else{
memset(pTokenizer, 0, sizeof(fts5_tokenizer));
rc = SQLITE_ERROR;
}
return rc;
}
int sqlite3Fts5GetTokenizer(
Fts5Global *pGlobal,
const char **azArg,
int nArg,
Fts5Tokenizer **ppTok,
fts5_tokenizer **ppTokApi
){
Fts5TokenizerModule *pMod = 0;
int rc = SQLITE_OK;
if( nArg==0 ){
pMod = pGlobal->pTok;
}else{
for(pMod=pGlobal->pTok; pMod; pMod=pMod->pNext){
if( sqlite3_stricmp(azArg[0], pMod->zName)==0 ) break;
}
}
if( pMod==0 ){
rc = SQLITE_ERROR;
}else{
rc = pMod->x.xCreate(pMod->pUserData, &azArg[1], (nArg?nArg-1:0), ppTok);
*ppTokApi = &pMod->x;
}
if( rc!=SQLITE_OK ){
*ppTokApi = 0;
*ppTok = 0;
}
return rc;
}
static void fts5ModuleDestroy(void *pCtx){
Fts5TokenizerModule *pTok, *pNextTok;
Fts5Auxiliary *pAux, *pNextAux;
Fts5Global *pGlobal = (Fts5Global*)pCtx;
for(pAux=pGlobal->pAux; pAux; pAux=pNextAux){
pNextAux = pAux->pNext;
if( pAux->xDestroy ) pAux->xDestroy(pAux->pUserData);
sqlite3_free(pAux);
}
for(pTok=pGlobal->pTok; pTok; pTok=pNextTok){
pNextTok = pTok->pNext;
if( pTok->xDestroy ) pTok->xDestroy(pTok->pUserData);
sqlite3_free(pTok);
}
sqlite3_free(pGlobal);
}
static void fts5Fts5Func(
sqlite3_context *pCtx, /* Function call context */
int nArg, /* Number of args */
sqlite3_value **apVal /* Function arguments */
){
Fts5Global *pGlobal = (Fts5Global*)sqlite3_user_data(pCtx);
char buf[8];
assert( nArg==0 );
assert( sizeof(buf)>=sizeof(pGlobal) );
memcpy(buf, (void*)&pGlobal, sizeof(pGlobal));
sqlite3_result_blob(pCtx, buf, sizeof(pGlobal), SQLITE_TRANSIENT);
}
int sqlite3Fts5Init(sqlite3 *db){
static const sqlite3_module fts5Mod = {
/* iVersion */ 2,
/* xCreate */ fts5CreateMethod,
/* xConnect */ fts5ConnectMethod,
/* xBestIndex */ fts5BestIndexMethod,
/* xDisconnect */ fts5DisconnectMethod,
/* xDestroy */ fts5DestroyMethod,
/* xOpen */ fts5OpenMethod,
/* xClose */ fts5CloseMethod,
/* xFilter */ fts5FilterMethod,
/* xNext */ fts5NextMethod,
/* xEof */ fts5EofMethod,
/* xColumn */ fts5ColumnMethod,
/* xRowid */ fts5RowidMethod,
/* xUpdate */ fts5UpdateMethod,
/* xBegin */ fts5BeginMethod,
/* xSync */ fts5SyncMethod,
/* xCommit */ fts5CommitMethod,
/* xRollback */ fts5RollbackMethod,
/* xFindFunction */ fts5FindFunctionMethod,
/* xRename */ fts5RenameMethod,
/* xSavepoint */ fts5SavepointMethod,
/* xRelease */ fts5ReleaseMethod,
/* xRollbackTo */ fts5RollbackToMethod,
};
int rc;
Fts5Global *pGlobal = 0;
pGlobal = (Fts5Global*)sqlite3_malloc(sizeof(Fts5Global));
if( pGlobal==0 ){
rc = SQLITE_NOMEM;
}else{
void *p = (void*)pGlobal;
memset(pGlobal, 0, sizeof(Fts5Global));
pGlobal->db = db;
pGlobal->api.iVersion = 1;
pGlobal->api.xCreateFunction = fts5CreateAux;
pGlobal->api.xCreateTokenizer = fts5CreateTokenizer;
pGlobal->api.xFindTokenizer = fts5FindTokenizer;
rc = sqlite3_create_module_v2(db, "fts5", &fts5Mod, p, fts5ModuleDestroy);
if( rc==SQLITE_OK ) rc = sqlite3Fts5IndexInit(db);
if( rc==SQLITE_OK ) rc = sqlite3Fts5ExprInit(pGlobal, db);
if( rc==SQLITE_OK ) rc = sqlite3Fts5AuxInit(&pGlobal->api);
if( rc==SQLITE_OK ) rc = sqlite3Fts5TokenizerInit(&pGlobal->api);
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(
db, "fts5", 0, SQLITE_UTF8, p, fts5Fts5Func, 0, 0
);
}
}
return rc;
}