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diff --git a/src/vtab.c b/src/vtab.c
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+/*
+** 2006 June 10
+**
+** 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 contains code used to help implement virtual tables.
+*/
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+#include "sqliteInt.h"
+
+/*
+** Before a virtual table xCreate() or xConnect() method is invoked, the
+** sqlite3.pVtabCtx member variable is set to point to an instance of
+** this struct allocated on the stack. It is used by the implementation of
+** the sqlite3_declare_vtab() and sqlite3_vtab_config() APIs, both of which
+** are invoked only from within xCreate and xConnect methods.
+*/
+struct VtabCtx {
+ VTable *pVTable; /* The virtual table being constructed */
+ Table *pTab; /* The Table object to which the virtual table belongs */
+ VtabCtx *pPrior; /* Parent context (if any) */
+ int bDeclared; /* True after sqlite3_declare_vtab() is called */
+};
+
+/*
+** Construct and install a Module object for a virtual table. When this
+** routine is called, it is guaranteed that all appropriate locks are held
+** and the module is not already part of the connection.
+**
+** If there already exists a module with zName, replace it with the new one.
+** If pModule==0, then delete the module zName if it exists.
+*/
+Module *sqlite3VtabCreateModule(
+ sqlite3 *db, /* Database in which module is registered */
+ const char *zName, /* Name assigned to this module */
+ const sqlite3_module *pModule, /* The definition of the module */
+ void *pAux, /* Context pointer for xCreate/xConnect */
+ void (*xDestroy)(void *) /* Module destructor function */
+){
+ Module *pMod;
+ Module *pDel;
+ char *zCopy;
+ if( pModule==0 ){
+ zCopy = (char*)zName;
+ pMod = 0;
+ }else{
+ int nName = sqlite3Strlen30(zName);
+ pMod = (Module *)sqlite3Malloc(sizeof(Module) + nName + 1);
+ if( pMod==0 ){
+ sqlite3OomFault(db);
+ return 0;
+ }
+ zCopy = (char *)(&pMod[1]);
+ memcpy(zCopy, zName, nName+1);
+ pMod->zName = zCopy;
+ pMod->pModule = pModule;
+ pMod->pAux = pAux;
+ pMod->xDestroy = xDestroy;
+ pMod->pEpoTab = 0;
+ pMod->nRefModule = 1;
+ }
+ pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod);
+ if( pDel ){
+ if( pDel==pMod ){
+ sqlite3OomFault(db);
+ sqlite3DbFree(db, pDel);
+ pMod = 0;
+ }else{
+ sqlite3VtabEponymousTableClear(db, pDel);
+ sqlite3VtabModuleUnref(db, pDel);
+ }
+ }
+ return pMod;
+}
+
+/*
+** The actual function that does the work of creating a new module.
+** This function implements the sqlite3_create_module() and
+** sqlite3_create_module_v2() interfaces.
+*/
+static int createModule(
+ sqlite3 *db, /* Database in which module is registered */
+ const char *zName, /* Name assigned to this module */
+ const sqlite3_module *pModule, /* The definition of the module */
+ void *pAux, /* Context pointer for xCreate/xConnect */
+ void (*xDestroy)(void *) /* Module destructor function */
+){
+ int rc = SQLITE_OK;
+
+ sqlite3_mutex_enter(db->mutex);
+ (void)sqlite3VtabCreateModule(db, zName, pModule, pAux, xDestroy);
+ rc = sqlite3ApiExit(db, rc);
+ if( rc!=SQLITE_OK && xDestroy ) xDestroy(pAux);
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+
+/*
+** External API function used to create a new virtual-table module.
+*/
+int sqlite3_create_module(
+ sqlite3 *db, /* Database in which module is registered */
+ const char *zName, /* Name assigned to this module */
+ const sqlite3_module *pModule, /* The definition of the module */
+ void *pAux /* Context pointer for xCreate/xConnect */
+){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+ return createModule(db, zName, pModule, pAux, 0);
+}
+
+/*
+** External API function used to create a new virtual-table module.
+*/
+int sqlite3_create_module_v2(
+ sqlite3 *db, /* Database in which module is registered */
+ const char *zName, /* Name assigned to this module */
+ const sqlite3_module *pModule, /* The definition of the module */
+ void *pAux, /* Context pointer for xCreate/xConnect */
+ void (*xDestroy)(void *) /* Module destructor function */
+){
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) || zName==0 ) return SQLITE_MISUSE_BKPT;
+#endif
+ return createModule(db, zName, pModule, pAux, xDestroy);
+}
+
+/*
+** External API to drop all virtual-table modules, except those named
+** on the azNames list.
+*/
+int sqlite3_drop_modules(sqlite3 *db, const char** azNames){
+ HashElem *pThis, *pNext;
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
+ for(pThis=sqliteHashFirst(&db->aModule); pThis; pThis=pNext){
+ Module *pMod = (Module*)sqliteHashData(pThis);
+ pNext = sqliteHashNext(pThis);
+ if( azNames ){
+ int ii;
+ for(ii=0; azNames[ii]!=0 && strcmp(azNames[ii],pMod->zName)!=0; ii++){}
+ if( azNames[ii]!=0 ) continue;
+ }
+ createModule(db, pMod->zName, 0, 0, 0);
+ }
+ return SQLITE_OK;
+}
+
+/*
+** Decrement the reference count on a Module object. Destroy the
+** module when the reference count reaches zero.
+*/
+void sqlite3VtabModuleUnref(sqlite3 *db, Module *pMod){
+ assert( pMod->nRefModule>0 );
+ pMod->nRefModule--;
+ if( pMod->nRefModule==0 ){
+ if( pMod->xDestroy ){
+ pMod->xDestroy(pMod->pAux);
+ }
+ assert( pMod->pEpoTab==0 );
+ sqlite3DbFree(db, pMod);
+ }
+}
+
+/*
+** Lock the virtual table so that it cannot be disconnected.
+** Locks nest. Every lock should have a corresponding unlock.
+** If an unlock is omitted, resources leaks will occur.
+**
+** If a disconnect is attempted while a virtual table is locked,
+** the disconnect is deferred until all locks have been removed.
+*/
+void sqlite3VtabLock(VTable *pVTab){
+ pVTab->nRef++;
+}
+
+
+/*
+** pTab is a pointer to a Table structure representing a virtual-table.
+** Return a pointer to the VTable object used by connection db to access
+** this virtual-table, if one has been created, or NULL otherwise.
+*/
+VTable *sqlite3GetVTable(sqlite3 *db, Table *pTab){
+ VTable *pVtab;
+ assert( IsVirtual(pTab) );
+ for(pVtab=pTab->u.vtab.p; pVtab && pVtab->db!=db; pVtab=pVtab->pNext);
+ return pVtab;
+}
+
+/*
+** Decrement the ref-count on a virtual table object. When the ref-count
+** reaches zero, call the xDisconnect() method to delete the object.
+*/
+void sqlite3VtabUnlock(VTable *pVTab){
+ sqlite3 *db = pVTab->db;
+
+ assert( db );
+ assert( pVTab->nRef>0 );
+ assert( db->eOpenState==SQLITE_STATE_OPEN
+ || db->eOpenState==SQLITE_STATE_ZOMBIE );
+
+ pVTab->nRef--;
+ if( pVTab->nRef==0 ){
+ sqlite3_vtab *p = pVTab->pVtab;
+ if( p ){
+ p->pModule->xDisconnect(p);
+ }
+ sqlite3VtabModuleUnref(pVTab->db, pVTab->pMod);
+ sqlite3DbFree(db, pVTab);
+ }
+}
+
+/*
+** Table p is a virtual table. This function moves all elements in the
+** p->u.vtab.p list to the sqlite3.pDisconnect lists of their associated
+** database connections to be disconnected at the next opportunity.
+** Except, if argument db is not NULL, then the entry associated with
+** connection db is left in the p->u.vtab.p list.
+*/
+static VTable *vtabDisconnectAll(sqlite3 *db, Table *p){
+ VTable *pRet = 0;
+ VTable *pVTable;
+
+ assert( IsVirtual(p) );
+ pVTable = p->u.vtab.p;
+ p->u.vtab.p = 0;
+
+ /* Assert that the mutex (if any) associated with the BtShared database
+ ** that contains table p is held by the caller. See header comments
+ ** above function sqlite3VtabUnlockList() for an explanation of why
+ ** this makes it safe to access the sqlite3.pDisconnect list of any
+ ** database connection that may have an entry in the p->u.vtab.p list.
+ */
+ assert( db==0 || sqlite3SchemaMutexHeld(db, 0, p->pSchema) );
+
+ while( pVTable ){
+ sqlite3 *db2 = pVTable->db;
+ VTable *pNext = pVTable->pNext;
+ assert( db2 );
+ if( db2==db ){
+ pRet = pVTable;
+ p->u.vtab.p = pRet;
+ pRet->pNext = 0;
+ }else{
+ pVTable->pNext = db2->pDisconnect;
+ db2->pDisconnect = pVTable;
+ }
+ pVTable = pNext;
+ }
+
+ assert( !db || pRet );
+ return pRet;
+}
+
+/*
+** Table *p is a virtual table. This function removes the VTable object
+** for table *p associated with database connection db from the linked
+** list in p->pVTab. It also decrements the VTable ref count. This is
+** used when closing database connection db to free all of its VTable
+** objects without disturbing the rest of the Schema object (which may
+** be being used by other shared-cache connections).
+*/
+void sqlite3VtabDisconnect(sqlite3 *db, Table *p){
+ VTable **ppVTab;
+
+ assert( IsVirtual(p) );
+ assert( sqlite3BtreeHoldsAllMutexes(db) );
+ assert( sqlite3_mutex_held(db->mutex) );
+
+ for(ppVTab=&p->u.vtab.p; *ppVTab; ppVTab=&(*ppVTab)->pNext){
+ if( (*ppVTab)->db==db ){
+ VTable *pVTab = *ppVTab;
+ *ppVTab = pVTab->pNext;
+ sqlite3VtabUnlock(pVTab);
+ break;
+ }
+ }
+}
+
+
+/*
+** Disconnect all the virtual table objects in the sqlite3.pDisconnect list.
+**
+** This function may only be called when the mutexes associated with all
+** shared b-tree databases opened using connection db are held by the
+** caller. This is done to protect the sqlite3.pDisconnect list. The
+** sqlite3.pDisconnect list is accessed only as follows:
+**
+** 1) By this function. In this case, all BtShared mutexes and the mutex
+** associated with the database handle itself must be held.
+**
+** 2) By function vtabDisconnectAll(), when it adds a VTable entry to
+** the sqlite3.pDisconnect list. In this case either the BtShared mutex
+** associated with the database the virtual table is stored in is held
+** or, if the virtual table is stored in a non-sharable database, then
+** the database handle mutex is held.
+**
+** As a result, a sqlite3.pDisconnect cannot be accessed simultaneously
+** by multiple threads. It is thread-safe.
+*/
+void sqlite3VtabUnlockList(sqlite3 *db){
+ VTable *p = db->pDisconnect;
+
+ assert( sqlite3BtreeHoldsAllMutexes(db) );
+ assert( sqlite3_mutex_held(db->mutex) );
+
+ if( p ){
+ db->pDisconnect = 0;
+ do {
+ VTable *pNext = p->pNext;
+ sqlite3VtabUnlock(p);
+ p = pNext;
+ }while( p );
+ }
+}
+
+/*
+** Clear any and all virtual-table information from the Table record.
+** This routine is called, for example, just before deleting the Table
+** record.
+**
+** Since it is a virtual-table, the Table structure contains a pointer
+** to the head of a linked list of VTable structures. Each VTable
+** structure is associated with a single sqlite3* user of the schema.
+** The reference count of the VTable structure associated with database
+** connection db is decremented immediately (which may lead to the
+** structure being xDisconnected and free). Any other VTable structures
+** in the list are moved to the sqlite3.pDisconnect list of the associated
+** database connection.
+*/
+void sqlite3VtabClear(sqlite3 *db, Table *p){
+ assert( IsVirtual(p) );
+ assert( db!=0 );
+ if( db->pnBytesFreed==0 ) vtabDisconnectAll(0, p);
+ if( p->u.vtab.azArg ){
+ int i;
+ for(i=0; i<p->u.vtab.nArg; i++){
+ if( i!=1 ) sqlite3DbFree(db, p->u.vtab.azArg[i]);
+ }
+ sqlite3DbFree(db, p->u.vtab.azArg);
+ }
+}
+
+/*
+** Add a new module argument to pTable->u.vtab.azArg[].
+** The string is not copied - the pointer is stored. The
+** string will be freed automatically when the table is
+** deleted.
+*/
+static void addModuleArgument(Parse *pParse, Table *pTable, char *zArg){
+ sqlite3_int64 nBytes;
+ char **azModuleArg;
+ sqlite3 *db = pParse->db;
+
+ assert( IsVirtual(pTable) );
+ nBytes = sizeof(char *)*(2+pTable->u.vtab.nArg);
+ if( pTable->u.vtab.nArg+3>=db->aLimit[SQLITE_LIMIT_COLUMN] ){
+ sqlite3ErrorMsg(pParse, "too many columns on %s", pTable->zName);
+ }
+ azModuleArg = sqlite3DbRealloc(db, pTable->u.vtab.azArg, nBytes);
+ if( azModuleArg==0 ){
+ sqlite3DbFree(db, zArg);
+ }else{
+ int i = pTable->u.vtab.nArg++;
+ azModuleArg[i] = zArg;
+ azModuleArg[i+1] = 0;
+ pTable->u.vtab.azArg = azModuleArg;
+ }
+}
+
+/*
+** The parser calls this routine when it first sees a CREATE VIRTUAL TABLE
+** statement. The module name has been parsed, but the optional list
+** of parameters that follow the module name are still pending.
+*/
+void sqlite3VtabBeginParse(
+ Parse *pParse, /* Parsing context */
+ Token *pName1, /* Name of new table, or database name */
+ Token *pName2, /* Name of new table or NULL */
+ Token *pModuleName, /* Name of the module for the virtual table */
+ int ifNotExists /* No error if the table already exists */
+){
+ Table *pTable; /* The new virtual table */
+ sqlite3 *db; /* Database connection */
+
+ sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, ifNotExists);
+ pTable = pParse->pNewTable;
+ if( pTable==0 ) return;
+ assert( 0==pTable->pIndex );
+ pTable->eTabType = TABTYP_VTAB;
+
+ db = pParse->db;
+
+ assert( pTable->u.vtab.nArg==0 );
+ addModuleArgument(pParse, pTable, sqlite3NameFromToken(db, pModuleName));
+ addModuleArgument(pParse, pTable, 0);
+ addModuleArgument(pParse, pTable, sqlite3DbStrDup(db, pTable->zName));
+ assert( (pParse->sNameToken.z==pName2->z && pName2->z!=0)
+ || (pParse->sNameToken.z==pName1->z && pName2->z==0)
+ );
+ pParse->sNameToken.n = (int)(
+ &pModuleName->z[pModuleName->n] - pParse->sNameToken.z
+ );
+
+#ifndef SQLITE_OMIT_AUTHORIZATION
+ /* Creating a virtual table invokes the authorization callback twice.
+ ** The first invocation, to obtain permission to INSERT a row into the
+ ** sqlite_schema table, has already been made by sqlite3StartTable().
+ ** The second call, to obtain permission to create the table, is made now.
+ */
+ if( pTable->u.vtab.azArg ){
+ int iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
+ assert( iDb>=0 ); /* The database the table is being created in */
+ sqlite3AuthCheck(pParse, SQLITE_CREATE_VTABLE, pTable->zName,
+ pTable->u.vtab.azArg[0], pParse->db->aDb[iDb].zDbSName);
+ }
+#endif
+}
+
+/*
+** This routine takes the module argument that has been accumulating
+** in pParse->zArg[] and appends it to the list of arguments on the
+** virtual table currently under construction in pParse->pTable.
+*/
+static void addArgumentToVtab(Parse *pParse){
+ if( pParse->sArg.z && pParse->pNewTable ){
+ const char *z = (const char*)pParse->sArg.z;
+ int n = pParse->sArg.n;
+ sqlite3 *db = pParse->db;
+ addModuleArgument(pParse, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
+ }
+}
+
+/*
+** The parser calls this routine after the CREATE VIRTUAL TABLE statement
+** has been completely parsed.
+*/
+void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
+ Table *pTab = pParse->pNewTable; /* The table being constructed */
+ sqlite3 *db = pParse->db; /* The database connection */
+
+ if( pTab==0 ) return;
+ assert( IsVirtual(pTab) );
+ addArgumentToVtab(pParse);
+ pParse->sArg.z = 0;
+ if( pTab->u.vtab.nArg<1 ) return;
+
+ /* If the CREATE VIRTUAL TABLE statement is being entered for the
+ ** first time (in other words if the virtual table is actually being
+ ** created now instead of just being read out of sqlite_schema) then
+ ** do additional initialization work and store the statement text
+ ** in the sqlite_schema table.
+ */
+ if( !db->init.busy ){
+ char *zStmt;
+ char *zWhere;
+ int iDb;
+ int iReg;
+ Vdbe *v;
+
+ sqlite3MayAbort(pParse);
+
+ /* Compute the complete text of the CREATE VIRTUAL TABLE statement */
+ if( pEnd ){
+ pParse->sNameToken.n = (int)(pEnd->z - pParse->sNameToken.z) + pEnd->n;
+ }
+ zStmt = sqlite3MPrintf(db, "CREATE VIRTUAL TABLE %T", &pParse->sNameToken);
+
+ /* A slot for the record has already been allocated in the
+ ** schema table. We just need to update that slot with all
+ ** the information we've collected.
+ **
+ ** The VM register number pParse->regRowid holds the rowid of an
+ ** entry in the sqlite_schema table that was created for this vtab
+ ** by sqlite3StartTable().
+ */
+ iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+ sqlite3NestedParse(pParse,
+ "UPDATE %Q." LEGACY_SCHEMA_TABLE " "
+ "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
+ "WHERE rowid=#%d",
+ db->aDb[iDb].zDbSName,
+ pTab->zName,
+ pTab->zName,
+ zStmt,
+ pParse->regRowid
+ );
+ v = sqlite3GetVdbe(pParse);
+ sqlite3ChangeCookie(pParse, iDb);
+
+ sqlite3VdbeAddOp0(v, OP_Expire);
+ zWhere = sqlite3MPrintf(db, "name=%Q AND sql=%Q", pTab->zName, zStmt);
+ sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere, 0);
+ sqlite3DbFree(db, zStmt);
+
+ iReg = ++pParse->nMem;
+ sqlite3VdbeLoadString(v, iReg, pTab->zName);
+ sqlite3VdbeAddOp2(v, OP_VCreate, iDb, iReg);
+ }else{
+ /* If we are rereading the sqlite_schema table create the in-memory
+ ** record of the table. */
+ Table *pOld;
+ Schema *pSchema = pTab->pSchema;
+ const char *zName = pTab->zName;
+ assert( zName!=0 );
+ sqlite3MarkAllShadowTablesOf(db, pTab);
+ pOld = sqlite3HashInsert(&pSchema->tblHash, zName, pTab);
+ if( pOld ){
+ sqlite3OomFault(db);
+ assert( pTab==pOld ); /* Malloc must have failed inside HashInsert() */
+ return;
+ }
+ pParse->pNewTable = 0;
+ }
+}
+
+/*
+** The parser calls this routine when it sees the first token
+** of an argument to the module name in a CREATE VIRTUAL TABLE statement.
+*/
+void sqlite3VtabArgInit(Parse *pParse){
+ addArgumentToVtab(pParse);
+ pParse->sArg.z = 0;
+ pParse->sArg.n = 0;
+}
+
+/*
+** The parser calls this routine for each token after the first token
+** in an argument to the module name in a CREATE VIRTUAL TABLE statement.
+*/
+void sqlite3VtabArgExtend(Parse *pParse, Token *p){
+ Token *pArg = &pParse->sArg;
+ if( pArg->z==0 ){
+ pArg->z = p->z;
+ pArg->n = p->n;
+ }else{
+ assert(pArg->z <= p->z);
+ pArg->n = (int)(&p->z[p->n] - pArg->z);
+ }
+}
+
+/*
+** Invoke a virtual table constructor (either xCreate or xConnect). The
+** pointer to the function to invoke is passed as the fourth parameter
+** to this procedure.
+*/
+static int vtabCallConstructor(
+ sqlite3 *db,
+ Table *pTab,
+ Module *pMod,
+ int (*xConstruct)(sqlite3*,void*,int,const char*const*,sqlite3_vtab**,char**),
+ char **pzErr
+){
+ VtabCtx sCtx;
+ VTable *pVTable;
+ int rc;
+ const char *const*azArg;
+ int nArg = pTab->u.vtab.nArg;
+ char *zErr = 0;
+ char *zModuleName;
+ int iDb;
+ VtabCtx *pCtx;
+
+ assert( IsVirtual(pTab) );
+ azArg = (const char *const*)pTab->u.vtab.azArg;
+
+ /* Check that the virtual-table is not already being initialized */
+ for(pCtx=db->pVtabCtx; pCtx; pCtx=pCtx->pPrior){
+ if( pCtx->pTab==pTab ){
+ *pzErr = sqlite3MPrintf(db,
+ "vtable constructor called recursively: %s", pTab->zName
+ );
+ return SQLITE_LOCKED;
+ }
+ }
+
+ zModuleName = sqlite3DbStrDup(db, pTab->zName);
+ if( !zModuleName ){
+ return SQLITE_NOMEM_BKPT;
+ }
+
+ pVTable = sqlite3MallocZero(sizeof(VTable));
+ if( !pVTable ){
+ sqlite3OomFault(db);
+ sqlite3DbFree(db, zModuleName);
+ return SQLITE_NOMEM_BKPT;
+ }
+ pVTable->db = db;
+ pVTable->pMod = pMod;
+ pVTable->eVtabRisk = SQLITE_VTABRISK_Normal;
+
+ iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+ pTab->u.vtab.azArg[1] = db->aDb[iDb].zDbSName;
+
+ /* Invoke the virtual table constructor */
+ assert( &db->pVtabCtx );
+ assert( xConstruct );
+ sCtx.pTab = pTab;
+ sCtx.pVTable = pVTable;
+ sCtx.pPrior = db->pVtabCtx;
+ sCtx.bDeclared = 0;
+ db->pVtabCtx = &sCtx;
+ pTab->nTabRef++;
+ rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
+ sqlite3DeleteTable(db, pTab);
+ db->pVtabCtx = sCtx.pPrior;
+ if( rc==SQLITE_NOMEM ) sqlite3OomFault(db);
+ assert( sCtx.pTab==pTab );
+
+ if( SQLITE_OK!=rc ){
+ if( zErr==0 ){
+ *pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
+ }else {
+ *pzErr = sqlite3MPrintf(db, "%s", zErr);
+ sqlite3_free(zErr);
+ }
+ sqlite3DbFree(db, pVTable);
+ }else if( ALWAYS(pVTable->pVtab) ){
+ /* Justification of ALWAYS(): A correct vtab constructor must allocate
+ ** the sqlite3_vtab object if successful. */
+ memset(pVTable->pVtab, 0, sizeof(pVTable->pVtab[0]));
+ pVTable->pVtab->pModule = pMod->pModule;
+ pMod->nRefModule++;
+ pVTable->nRef = 1;
+ if( sCtx.bDeclared==0 ){
+ const char *zFormat = "vtable constructor did not declare schema: %s";
+ *pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
+ sqlite3VtabUnlock(pVTable);
+ rc = SQLITE_ERROR;
+ }else{
+ int iCol;
+ u16 oooHidden = 0;
+ /* If everything went according to plan, link the new VTable structure
+ ** into the linked list headed by pTab->u.vtab.p. Then loop through the
+ ** columns of the table to see if any of them contain the token "hidden".
+ ** If so, set the Column COLFLAG_HIDDEN flag and remove the token from
+ ** the type string. */
+ pVTable->pNext = pTab->u.vtab.p;
+ pTab->u.vtab.p = pVTable;
+
+ for(iCol=0; iCol<pTab->nCol; iCol++){
+ char *zType = sqlite3ColumnType(&pTab->aCol[iCol], "");
+ int nType;
+ int i = 0;
+ nType = sqlite3Strlen30(zType);
+ for(i=0; i<nType; i++){
+ if( 0==sqlite3StrNICmp("hidden", &zType[i], 6)
+ && (i==0 || zType[i-1]==' ')
+ && (zType[i+6]=='\0' || zType[i+6]==' ')
+ ){
+ break;
+ }
+ }
+ if( i<nType ){
+ int j;
+ int nDel = 6 + (zType[i+6] ? 1 : 0);
+ for(j=i; (j+nDel)<=nType; j++){
+ zType[j] = zType[j+nDel];
+ }
+ if( zType[i]=='\0' && i>0 ){
+ assert(zType[i-1]==' ');
+ zType[i-1] = '\0';
+ }
+ pTab->aCol[iCol].colFlags |= COLFLAG_HIDDEN;
+ pTab->tabFlags |= TF_HasHidden;
+ oooHidden = TF_OOOHidden;
+ }else{
+ pTab->tabFlags |= oooHidden;
+ }
+ }
+ }
+ }
+
+ sqlite3DbFree(db, zModuleName);
+ return rc;
+}
+
+/*
+** This function is invoked by the parser to call the xConnect() method
+** of the virtual table pTab. If an error occurs, an error code is returned
+** and an error left in pParse.
+**
+** This call is a no-op if table pTab is not a virtual table.
+*/
+int sqlite3VtabCallConnect(Parse *pParse, Table *pTab){
+ sqlite3 *db = pParse->db;
+ const char *zMod;
+ Module *pMod;
+ int rc;
+
+ assert( pTab );
+ assert( IsVirtual(pTab) );
+ if( sqlite3GetVTable(db, pTab) ){
+ return SQLITE_OK;
+ }
+
+ /* Locate the required virtual table module */
+ zMod = pTab->u.vtab.azArg[0];
+ pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);
+
+ if( !pMod ){
+ const char *zModule = pTab->u.vtab.azArg[0];
+ sqlite3ErrorMsg(pParse, "no such module: %s", zModule);
+ rc = SQLITE_ERROR;
+ }else{
+ char *zErr = 0;
+ rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xConnect, &zErr);
+ if( rc!=SQLITE_OK ){
+ sqlite3ErrorMsg(pParse, "%s", zErr);
+ pParse->rc = rc;
+ }
+ sqlite3DbFree(db, zErr);
+ }
+
+ return rc;
+}
+/*
+** Grow the db->aVTrans[] array so that there is room for at least one
+** more v-table. Return SQLITE_NOMEM if a malloc fails, or SQLITE_OK otherwise.
+*/
+static int growVTrans(sqlite3 *db){
+ const int ARRAY_INCR = 5;
+
+ /* Grow the sqlite3.aVTrans array if required */
+ if( (db->nVTrans%ARRAY_INCR)==0 ){
+ VTable **aVTrans;
+ sqlite3_int64 nBytes = sizeof(sqlite3_vtab*)*
+ ((sqlite3_int64)db->nVTrans + ARRAY_INCR);
+ aVTrans = sqlite3DbRealloc(db, (void *)db->aVTrans, nBytes);
+ if( !aVTrans ){
+ return SQLITE_NOMEM_BKPT;
+ }
+ memset(&aVTrans[db->nVTrans], 0, sizeof(sqlite3_vtab *)*ARRAY_INCR);
+ db->aVTrans = aVTrans;
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** Add the virtual table pVTab to the array sqlite3.aVTrans[]. Space should
+** have already been reserved using growVTrans().
+*/
+static void addToVTrans(sqlite3 *db, VTable *pVTab){
+ /* Add pVtab to the end of sqlite3.aVTrans */
+ db->aVTrans[db->nVTrans++] = pVTab;
+ sqlite3VtabLock(pVTab);
+}
+
+/*
+** This function is invoked by the vdbe to call the xCreate method
+** of the virtual table named zTab in database iDb.
+**
+** If an error occurs, *pzErr is set to point to an English language
+** description of the error and an SQLITE_XXX error code is returned.
+** In this case the caller must call sqlite3DbFree(db, ) on *pzErr.
+*/
+int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
+ int rc = SQLITE_OK;
+ Table *pTab;
+ Module *pMod;
+ const char *zMod;
+
+ pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zDbSName);
+ assert( pTab && IsVirtual(pTab) && !pTab->u.vtab.p );
+
+ /* Locate the required virtual table module */
+ zMod = pTab->u.vtab.azArg[0];
+ pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);
+
+ /* If the module has been registered and includes a Create method,
+ ** invoke it now. If the module has not been registered, return an
+ ** error. Otherwise, do nothing.
+ */
+ if( pMod==0 || pMod->pModule->xCreate==0 || pMod->pModule->xDestroy==0 ){
+ *pzErr = sqlite3MPrintf(db, "no such module: %s", zMod);
+ rc = SQLITE_ERROR;
+ }else{
+ rc = vtabCallConstructor(db, pTab, pMod, pMod->pModule->xCreate, pzErr);
+ }
+
+ /* Justification of ALWAYS(): The xConstructor method is required to
+ ** create a valid sqlite3_vtab if it returns SQLITE_OK. */
+ if( rc==SQLITE_OK && ALWAYS(sqlite3GetVTable(db, pTab)) ){
+ rc = growVTrans(db);
+ if( rc==SQLITE_OK ){
+ addToVTrans(db, sqlite3GetVTable(db, pTab));
+ }
+ }
+
+ return rc;
+}
+
+/*
+** This function is used to set the schema of a virtual table. It is only
+** valid to call this function from within the xCreate() or xConnect() of a
+** virtual table module.
+*/
+int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
+ VtabCtx *pCtx;
+ int rc = SQLITE_OK;
+ Table *pTab;
+ Parse sParse;
+ int initBusy;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) || zCreateTable==0 ){
+ return SQLITE_MISUSE_BKPT;
+ }
+#endif
+ sqlite3_mutex_enter(db->mutex);
+ pCtx = db->pVtabCtx;
+ if( !pCtx || pCtx->bDeclared ){
+ sqlite3Error(db, SQLITE_MISUSE_BKPT);
+ sqlite3_mutex_leave(db->mutex);
+ return SQLITE_MISUSE_BKPT;
+ }
+ pTab = pCtx->pTab;
+ assert( IsVirtual(pTab) );
+
+ sqlite3ParseObjectInit(&sParse, db);
+ sParse.eParseMode = PARSE_MODE_DECLARE_VTAB;
+ sParse.disableTriggers = 1;
+ /* We should never be able to reach this point while loading the
+ ** schema. Nevertheless, defend against that (turn off db->init.busy)
+ ** in case a bug arises. */
+ assert( db->init.busy==0 );
+ initBusy = db->init.busy;
+ db->init.busy = 0;
+ sParse.nQueryLoop = 1;
+ if( SQLITE_OK==sqlite3RunParser(&sParse, zCreateTable)
+ && ALWAYS(sParse.pNewTable!=0)
+ && ALWAYS(!db->mallocFailed)
+ && IsOrdinaryTable(sParse.pNewTable)
+ ){
+ assert( sParse.zErrMsg==0 );
+ if( !pTab->aCol ){
+ Table *pNew = sParse.pNewTable;
+ Index *pIdx;
+ pTab->aCol = pNew->aCol;
+ sqlite3ExprListDelete(db, pNew->u.tab.pDfltList);
+ pTab->nNVCol = pTab->nCol = pNew->nCol;
+ pTab->tabFlags |= pNew->tabFlags & (TF_WithoutRowid|TF_NoVisibleRowid);
+ pNew->nCol = 0;
+ pNew->aCol = 0;
+ assert( pTab->pIndex==0 );
+ assert( HasRowid(pNew) || sqlite3PrimaryKeyIndex(pNew)!=0 );
+ if( !HasRowid(pNew)
+ && pCtx->pVTable->pMod->pModule->xUpdate!=0
+ && sqlite3PrimaryKeyIndex(pNew)->nKeyCol!=1
+ ){
+ /* WITHOUT ROWID virtual tables must either be read-only (xUpdate==0)
+ ** or else must have a single-column PRIMARY KEY */
+ rc = SQLITE_ERROR;
+ }
+ pIdx = pNew->pIndex;
+ if( pIdx ){
+ assert( pIdx->pNext==0 );
+ pTab->pIndex = pIdx;
+ pNew->pIndex = 0;
+ pIdx->pTable = pTab;
+ }
+ }
+ pCtx->bDeclared = 1;
+ }else{
+ sqlite3ErrorWithMsg(db, SQLITE_ERROR,
+ (sParse.zErrMsg ? "%s" : 0), sParse.zErrMsg);
+ sqlite3DbFree(db, sParse.zErrMsg);
+ rc = SQLITE_ERROR;
+ }
+ sParse.eParseMode = PARSE_MODE_NORMAL;
+
+ if( sParse.pVdbe ){
+ sqlite3VdbeFinalize(sParse.pVdbe);
+ }
+ sqlite3DeleteTable(db, sParse.pNewTable);
+ sqlite3ParseObjectReset(&sParse);
+ db->init.busy = initBusy;
+
+ assert( (rc&0xff)==rc );
+ rc = sqlite3ApiExit(db, rc);
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+/*
+** This function is invoked by the vdbe to call the xDestroy method
+** of the virtual table named zTab in database iDb. This occurs
+** when a DROP TABLE is mentioned.
+**
+** This call is a no-op if zTab is not a virtual table.
+*/
+int sqlite3VtabCallDestroy(sqlite3 *db, int iDb, const char *zTab){
+ int rc = SQLITE_OK;
+ Table *pTab;
+
+ pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zDbSName);
+ if( ALWAYS(pTab!=0)
+ && ALWAYS(IsVirtual(pTab))
+ && ALWAYS(pTab->u.vtab.p!=0)
+ ){
+ VTable *p;
+ int (*xDestroy)(sqlite3_vtab *);
+ for(p=pTab->u.vtab.p; p; p=p->pNext){
+ assert( p->pVtab );
+ if( p->pVtab->nRef>0 ){
+ return SQLITE_LOCKED;
+ }
+ }
+ p = vtabDisconnectAll(db, pTab);
+ xDestroy = p->pMod->pModule->xDestroy;
+ if( xDestroy==0 ) xDestroy = p->pMod->pModule->xDisconnect;
+ assert( xDestroy!=0 );
+ pTab->nTabRef++;
+ rc = xDestroy(p->pVtab);
+ /* Remove the sqlite3_vtab* from the aVTrans[] array, if applicable */
+ if( rc==SQLITE_OK ){
+ assert( pTab->u.vtab.p==p && p->pNext==0 );
+ p->pVtab = 0;
+ pTab->u.vtab.p = 0;
+ sqlite3VtabUnlock(p);
+ }
+ sqlite3DeleteTable(db, pTab);
+ }
+
+ return rc;
+}
+
+/*
+** This function invokes either the xRollback or xCommit method
+** of each of the virtual tables in the sqlite3.aVTrans array. The method
+** called is identified by the second argument, "offset", which is
+** the offset of the method to call in the sqlite3_module structure.
+**
+** The array is cleared after invoking the callbacks.
+*/
+static void callFinaliser(sqlite3 *db, int offset){
+ int i;
+ if( db->aVTrans ){
+ VTable **aVTrans = db->aVTrans;
+ db->aVTrans = 0;
+ for(i=0; i<db->nVTrans; i++){
+ VTable *pVTab = aVTrans[i];
+ sqlite3_vtab *p = pVTab->pVtab;
+ if( p ){
+ int (*x)(sqlite3_vtab *);
+ x = *(int (**)(sqlite3_vtab *))((char *)p->pModule + offset);
+ if( x ) x(p);
+ }
+ pVTab->iSavepoint = 0;
+ sqlite3VtabUnlock(pVTab);
+ }
+ sqlite3DbFree(db, aVTrans);
+ db->nVTrans = 0;
+ }
+}
+
+/*
+** Invoke the xSync method of all virtual tables in the sqlite3.aVTrans
+** array. Return the error code for the first error that occurs, or
+** SQLITE_OK if all xSync operations are successful.
+**
+** If an error message is available, leave it in p->zErrMsg.
+*/
+int sqlite3VtabSync(sqlite3 *db, Vdbe *p){
+ int i;
+ int rc = SQLITE_OK;
+ VTable **aVTrans = db->aVTrans;
+
+ db->aVTrans = 0;
+ for(i=0; rc==SQLITE_OK && i<db->nVTrans; i++){
+ int (*x)(sqlite3_vtab *);
+ sqlite3_vtab *pVtab = aVTrans[i]->pVtab;
+ if( pVtab && (x = pVtab->pModule->xSync)!=0 ){
+ rc = x(pVtab);
+ sqlite3VtabImportErrmsg(p, pVtab);
+ }
+ }
+ db->aVTrans = aVTrans;
+ return rc;
+}
+
+/*
+** Invoke the xRollback method of all virtual tables in the
+** sqlite3.aVTrans array. Then clear the array itself.
+*/
+int sqlite3VtabRollback(sqlite3 *db){
+ callFinaliser(db, offsetof(sqlite3_module,xRollback));
+ return SQLITE_OK;
+}
+
+/*
+** Invoke the xCommit method of all virtual tables in the
+** sqlite3.aVTrans array. Then clear the array itself.
+*/
+int sqlite3VtabCommit(sqlite3 *db){
+ callFinaliser(db, offsetof(sqlite3_module,xCommit));
+ return SQLITE_OK;
+}
+
+/*
+** If the virtual table pVtab supports the transaction interface
+** (xBegin/xRollback/xCommit and optionally xSync) and a transaction is
+** not currently open, invoke the xBegin method now.
+**
+** If the xBegin call is successful, place the sqlite3_vtab pointer
+** in the sqlite3.aVTrans array.
+*/
+int sqlite3VtabBegin(sqlite3 *db, VTable *pVTab){
+ int rc = SQLITE_OK;
+ const sqlite3_module *pModule;
+
+ /* Special case: If db->aVTrans is NULL and db->nVTrans is greater
+ ** than zero, then this function is being called from within a
+ ** virtual module xSync() callback. It is illegal to write to
+ ** virtual module tables in this case, so return SQLITE_LOCKED.
+ */
+ if( sqlite3VtabInSync(db) ){
+ return SQLITE_LOCKED;
+ }
+ if( !pVTab ){
+ return SQLITE_OK;
+ }
+ pModule = pVTab->pVtab->pModule;
+
+ if( pModule->xBegin ){
+ int i;
+
+ /* If pVtab is already in the aVTrans array, return early */
+ for(i=0; i<db->nVTrans; i++){
+ if( db->aVTrans[i]==pVTab ){
+ return SQLITE_OK;
+ }
+ }
+
+ /* Invoke the xBegin method. If successful, add the vtab to the
+ ** sqlite3.aVTrans[] array. */
+ rc = growVTrans(db);
+ if( rc==SQLITE_OK ){
+ rc = pModule->xBegin(pVTab->pVtab);
+ if( rc==SQLITE_OK ){
+ int iSvpt = db->nStatement + db->nSavepoint;
+ addToVTrans(db, pVTab);
+ if( iSvpt && pModule->xSavepoint ){
+ pVTab->iSavepoint = iSvpt;
+ rc = pModule->xSavepoint(pVTab->pVtab, iSvpt-1);
+ }
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** Invoke either the xSavepoint, xRollbackTo or xRelease method of all
+** virtual tables that currently have an open transaction. Pass iSavepoint
+** as the second argument to the virtual table method invoked.
+**
+** If op is SAVEPOINT_BEGIN, the xSavepoint method is invoked. If it is
+** SAVEPOINT_ROLLBACK, the xRollbackTo method. Otherwise, if op is
+** SAVEPOINT_RELEASE, then the xRelease method of each virtual table with
+** an open transaction is invoked.
+**
+** If any virtual table method returns an error code other than SQLITE_OK,
+** processing is abandoned and the error returned to the caller of this
+** function immediately. If all calls to virtual table methods are successful,
+** SQLITE_OK is returned.
+*/
+int sqlite3VtabSavepoint(sqlite3 *db, int op, int iSavepoint){
+ int rc = SQLITE_OK;
+
+ assert( op==SAVEPOINT_RELEASE||op==SAVEPOINT_ROLLBACK||op==SAVEPOINT_BEGIN );
+ assert( iSavepoint>=-1 );
+ if( db->aVTrans ){
+ int i;
+ for(i=0; rc==SQLITE_OK && i<db->nVTrans; i++){
+ VTable *pVTab = db->aVTrans[i];
+ const sqlite3_module *pMod = pVTab->pMod->pModule;
+ if( pVTab->pVtab && pMod->iVersion>=2 ){
+ int (*xMethod)(sqlite3_vtab *, int);
+ sqlite3VtabLock(pVTab);
+ switch( op ){
+ case SAVEPOINT_BEGIN:
+ xMethod = pMod->xSavepoint;
+ pVTab->iSavepoint = iSavepoint+1;
+ break;
+ case SAVEPOINT_ROLLBACK:
+ xMethod = pMod->xRollbackTo;
+ break;
+ default:
+ xMethod = pMod->xRelease;
+ break;
+ }
+ if( xMethod && pVTab->iSavepoint>iSavepoint ){
+ u64 savedFlags = (db->flags & SQLITE_Defensive);
+ db->flags &= ~(u64)SQLITE_Defensive;
+ rc = xMethod(pVTab->pVtab, iSavepoint);
+ db->flags |= savedFlags;
+ }
+ sqlite3VtabUnlock(pVTab);
+ }
+ }
+ }
+ return rc;
+}
+
+/*
+** The first parameter (pDef) is a function implementation. The
+** second parameter (pExpr) is the first argument to this function.
+** If pExpr is a column in a virtual table, then let the virtual
+** table implementation have an opportunity to overload the function.
+**
+** This routine is used to allow virtual table implementations to
+** overload MATCH, LIKE, GLOB, and REGEXP operators.
+**
+** Return either the pDef argument (indicating no change) or a
+** new FuncDef structure that is marked as ephemeral using the
+** SQLITE_FUNC_EPHEM flag.
+*/
+FuncDef *sqlite3VtabOverloadFunction(
+ sqlite3 *db, /* Database connection for reporting malloc problems */
+ FuncDef *pDef, /* Function to possibly overload */
+ int nArg, /* Number of arguments to the function */
+ Expr *pExpr /* First argument to the function */
+){
+ Table *pTab;
+ sqlite3_vtab *pVtab;
+ sqlite3_module *pMod;
+ void (*xSFunc)(sqlite3_context*,int,sqlite3_value**) = 0;
+ void *pArg = 0;
+ FuncDef *pNew;
+ int rc = 0;
+
+ /* Check to see the left operand is a column in a virtual table */
+ if( NEVER(pExpr==0) ) return pDef;
+ if( pExpr->op!=TK_COLUMN ) return pDef;
+ assert( ExprUseYTab(pExpr) );
+ pTab = pExpr->y.pTab;
+ if( NEVER(pTab==0) ) return pDef;
+ if( !IsVirtual(pTab) ) return pDef;
+ pVtab = sqlite3GetVTable(db, pTab)->pVtab;
+ assert( pVtab!=0 );
+ assert( pVtab->pModule!=0 );
+ pMod = (sqlite3_module *)pVtab->pModule;
+ if( pMod->xFindFunction==0 ) return pDef;
+
+ /* Call the xFindFunction method on the virtual table implementation
+ ** to see if the implementation wants to overload this function.
+ **
+ ** Though undocumented, we have historically always invoked xFindFunction
+ ** with an all lower-case function name. Continue in this tradition to
+ ** avoid any chance of an incompatibility.
+ */
+#ifdef SQLITE_DEBUG
+ {
+ int i;
+ for(i=0; pDef->zName[i]; i++){
+ unsigned char x = (unsigned char)pDef->zName[i];
+ assert( x==sqlite3UpperToLower[x] );
+ }
+ }
+#endif
+ rc = pMod->xFindFunction(pVtab, nArg, pDef->zName, &xSFunc, &pArg);
+ if( rc==0 ){
+ return pDef;
+ }
+
+ /* Create a new ephemeral function definition for the overloaded
+ ** function */
+ pNew = sqlite3DbMallocZero(db, sizeof(*pNew)
+ + sqlite3Strlen30(pDef->zName) + 1);
+ if( pNew==0 ){
+ return pDef;
+ }
+ *pNew = *pDef;
+ pNew->zName = (const char*)&pNew[1];
+ memcpy((char*)&pNew[1], pDef->zName, sqlite3Strlen30(pDef->zName)+1);
+ pNew->xSFunc = xSFunc;
+ pNew->pUserData = pArg;
+ pNew->funcFlags |= SQLITE_FUNC_EPHEM;
+ return pNew;
+}
+
+/*
+** Make sure virtual table pTab is contained in the pParse->apVirtualLock[]
+** array so that an OP_VBegin will get generated for it. Add pTab to the
+** array if it is missing. If pTab is already in the array, this routine
+** is a no-op.
+*/
+void sqlite3VtabMakeWritable(Parse *pParse, Table *pTab){
+ Parse *pToplevel = sqlite3ParseToplevel(pParse);
+ int i, n;
+ Table **apVtabLock;
+
+ assert( IsVirtual(pTab) );
+ for(i=0; i<pToplevel->nVtabLock; i++){
+ if( pTab==pToplevel->apVtabLock[i] ) return;
+ }
+ n = (pToplevel->nVtabLock+1)*sizeof(pToplevel->apVtabLock[0]);
+ apVtabLock = sqlite3Realloc(pToplevel->apVtabLock, n);
+ if( apVtabLock ){
+ pToplevel->apVtabLock = apVtabLock;
+ pToplevel->apVtabLock[pToplevel->nVtabLock++] = pTab;
+ }else{
+ sqlite3OomFault(pToplevel->db);
+ }
+}
+
+/*
+** Check to see if virtual table module pMod can be have an eponymous
+** virtual table instance. If it can, create one if one does not already
+** exist. Return non-zero if either the eponymous virtual table instance
+** exists when this routine returns or if an attempt to create it failed
+** and an error message was left in pParse.
+**
+** An eponymous virtual table instance is one that is named after its
+** module, and more importantly, does not require a CREATE VIRTUAL TABLE
+** statement in order to come into existence. Eponymous virtual table
+** instances always exist. They cannot be DROP-ed.
+**
+** Any virtual table module for which xConnect and xCreate are the same
+** method can have an eponymous virtual table instance.
+*/
+int sqlite3VtabEponymousTableInit(Parse *pParse, Module *pMod){
+ const sqlite3_module *pModule = pMod->pModule;
+ Table *pTab;
+ char *zErr = 0;
+ int rc;
+ sqlite3 *db = pParse->db;
+ if( pMod->pEpoTab ) return 1;
+ if( pModule->xCreate!=0 && pModule->xCreate!=pModule->xConnect ) return 0;
+ pTab = sqlite3DbMallocZero(db, sizeof(Table));
+ if( pTab==0 ) return 0;
+ pTab->zName = sqlite3DbStrDup(db, pMod->zName);
+ if( pTab->zName==0 ){
+ sqlite3DbFree(db, pTab);
+ return 0;
+ }
+ pMod->pEpoTab = pTab;
+ pTab->nTabRef = 1;
+ pTab->eTabType = TABTYP_VTAB;
+ pTab->pSchema = db->aDb[0].pSchema;
+ assert( pTab->u.vtab.nArg==0 );
+ pTab->iPKey = -1;
+ pTab->tabFlags |= TF_Eponymous;
+ addModuleArgument(pParse, pTab, sqlite3DbStrDup(db, pTab->zName));
+ addModuleArgument(pParse, pTab, 0);
+ addModuleArgument(pParse, pTab, sqlite3DbStrDup(db, pTab->zName));
+ rc = vtabCallConstructor(db, pTab, pMod, pModule->xConnect, &zErr);
+ if( rc ){
+ sqlite3ErrorMsg(pParse, "%s", zErr);
+ sqlite3DbFree(db, zErr);
+ sqlite3VtabEponymousTableClear(db, pMod);
+ }
+ return 1;
+}
+
+/*
+** Erase the eponymous virtual table instance associated with
+** virtual table module pMod, if it exists.
+*/
+void sqlite3VtabEponymousTableClear(sqlite3 *db, Module *pMod){
+ Table *pTab = pMod->pEpoTab;
+ if( pTab!=0 ){
+ /* Mark the table as Ephemeral prior to deleting it, so that the
+ ** sqlite3DeleteTable() routine will know that it is not stored in
+ ** the schema. */
+ pTab->tabFlags |= TF_Ephemeral;
+ sqlite3DeleteTable(db, pTab);
+ pMod->pEpoTab = 0;
+ }
+}
+
+/*
+** Return the ON CONFLICT resolution mode in effect for the virtual
+** table update operation currently in progress.
+**
+** The results of this routine are undefined unless it is called from
+** within an xUpdate method.
+*/
+int sqlite3_vtab_on_conflict(sqlite3 *db){
+ static const unsigned char aMap[] = {
+ SQLITE_ROLLBACK, SQLITE_ABORT, SQLITE_FAIL, SQLITE_IGNORE, SQLITE_REPLACE
+ };
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
+ assert( OE_Rollback==1 && OE_Abort==2 && OE_Fail==3 );
+ assert( OE_Ignore==4 && OE_Replace==5 );
+ assert( db->vtabOnConflict>=1 && db->vtabOnConflict<=5 );
+ return (int)aMap[db->vtabOnConflict-1];
+}
+
+/*
+** Call from within the xCreate() or xConnect() methods to provide
+** the SQLite core with additional information about the behavior
+** of the virtual table being implemented.
+*/
+int sqlite3_vtab_config(sqlite3 *db, int op, ...){
+ va_list ap;
+ int rc = SQLITE_OK;
+ VtabCtx *p;
+
+#ifdef SQLITE_ENABLE_API_ARMOR
+ if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
+#endif
+ sqlite3_mutex_enter(db->mutex);
+ p = db->pVtabCtx;
+ if( !p ){
+ rc = SQLITE_MISUSE_BKPT;
+ }else{
+ assert( p->pTab==0 || IsVirtual(p->pTab) );
+ va_start(ap, op);
+ switch( op ){
+ case SQLITE_VTAB_CONSTRAINT_SUPPORT: {
+ p->pVTable->bConstraint = (u8)va_arg(ap, int);
+ break;
+ }
+ case SQLITE_VTAB_INNOCUOUS: {
+ p->pVTable->eVtabRisk = SQLITE_VTABRISK_Low;
+ break;
+ }
+ case SQLITE_VTAB_DIRECTONLY: {
+ p->pVTable->eVtabRisk = SQLITE_VTABRISK_High;
+ break;
+ }
+ case SQLITE_VTAB_USES_ALL_SCHEMAS: {
+ p->pVTable->bAllSchemas = 1;
+ break;
+ }
+ default: {
+ rc = SQLITE_MISUSE_BKPT;
+ break;
+ }
+ }
+ va_end(ap);
+ }
+
+ if( rc!=SQLITE_OK ) sqlite3Error(db, rc);
+ sqlite3_mutex_leave(db->mutex);
+ return rc;
+}
+
+#endif /* SQLITE_OMIT_VIRTUALTABLE */