/*
** 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;
for(i=0; i<db->nVTrans && db->aVTrans[i]; i++){
sqlite3_vtab *pVtab = db->aVTrans[i];
int (*x)(sqlite3_vtab *);
x = *(int (**)(sqlite3_vtab *))((char *)pVtab->pModule + offset);
if( x ) x(pVtab);
sqlite3VtabUnlock(pVtab);
}
sqliteFree(db->aVTrans);
db->nVTrans = 0;
db->aVTrans = 0;
}
/*
** Clear any and all virtual-table information from the Table record.
** This routine is called, for example, just before deleting the Table
** record.
*/
void sqlite3VtabClear(Table *p){
sqlite3_vtab *pVtab = p->pVtab;
if( pVtab ){
assert( p->pMod && p->pMod->pModule );
sqlite3VtabUnlock(p->pSchema->db, pVtab);
p->pVtab = 0;
}
if( p->azModuleArg ){
int i;
for(i=0; i<p->nModuleArg; i++){
sqliteFree(p->azModuleArg[i]);
}
sqliteFree(p->azModuleArg);
}
}
/*
** 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;
db->pDisconnect = 0;
assert( sqlite3BtreeHoldsAllMutexes(db) );
assert( sqlite3_mutex_held(db->mutex) );
if( p ){
sqlite3ExpirePreparedStatements(db);
do {
VTable *pNext = p->pNext;
sqlite3VtabUnlock(p);
p = pNext;
}while( p );
}
}
/*
** 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->pVTable; *ppVTab; ppVTab=&(*ppVTab)->pNext){
if( (*ppVTab)->db==db ){
VTable *pVTab = *ppVTab;
*ppVTab = pVTab->pNext;
sqlite3VtabUnlock(pVTab);
break;
}
}
}
/*
** 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 ){
for(i=0; i<db->nVTrans; i++){
VTable *pVTab = db->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);
}
sqlite3VtabUnlock(pVTab);
}
sqlite3DbFree(db, db->aVTrans);
db->nVTrans = 0;
db->aVTrans = 0;
}
}
/*
** 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].zName);
if( ALWAYS(pTab!=0 && pTab->pVTable!=0) ){
VTable *p = vtabDisconnectAll(db, pTab);
assert( rc==SQLITE_OK );
rc = p->pMod->pModule->xDestroy(p->pVtab);
/* Remove the sqlite3_vtab* from the aVTrans[] array, if applicable */
if( rc==SQLITE_OK ){
assert( pTab->pVTable==p && p->pNext==0 );
p->pVtab = 0;
pTab->pVTable = 0;
sqlite3VtabUnlock(p);
}
}
return rc;
}
/*
** 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 = (const char *const*)pTab->azModuleArg;
int nArg = pTab->nModuleArg;
char *zErr = 0;
char *zModuleName;
int iDb;
VtabCtx *pCtx;
/* 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 = sqlite3MPrintf(db, "%s", pTab->zName);
if( !zModuleName ){
return SQLITE_NOMEM_BKPT;
}
pVTable = sqlite3DbMallocZero(db, sizeof(VTable));
if( !pVTable ){
sqlite3DbFree(db, zModuleName);
return SQLITE_NOMEM_BKPT;
}
pVTable->db = db;
pVTable->pMod = pMod;
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
pTab->azModuleArg[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;
rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
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;
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;
u8 oooHidden = 0;
/* If everything went according to plan, link the new VTable structure
** into the linked list headed by pTab->pVTable. 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->pVTable;
pTab->pVTable = 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;
oooHidden = TF_OOOHidden;
}else{
pTab->tabFlags |= oooHidden;
}
}
}
}
sqlite3DbFree(db, zModuleName);
return rc;
}
/*
** 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
){
VTable *pVTable;
int rc;
const char *const*azArg = (const char *const*)pTab->azModuleArg;
int nArg = pTab->nModuleArg;
char *zErr = 0;
char *zModuleName = sqlite3MPrintf(db, "%s", pTab->zName);
if( !zModuleName ){
return SQLITE_NOMEM;
}
pVTable = sqlite3DbMallocZero(db, sizeof(VTable));
if( !pVTable ){
sqlite3DbFree(db, zModuleName);
return SQLITE_NOMEM;
}
pVTable->db = db;
pVTable->pMod = pMod;
assert( !db->pVTab );
assert( xConstruct );
db->pVTab = pTab;
/* Invoke the virtual table constructor */
rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
if( SQLITE_OK!=rc ){
if( zErr==0 ){
*pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
}else {
*pzErr = sqlite3MPrintf(db, "%s", zErr);
sqlite3DbFree(db, zErr);
}
sqlite3DbFree(db, pVTable);
}else if( ALWAYS(pVTable->pVtab) ){
/* Justification of ALWAYS(): A correct vtab constructor must allocate
** the sqlite3_vtab object if successful. */
pVTable->pVtab->pModule = pMod->pModule;
pVTable->nRef = 1;
if( db->pVTab ){
const char *zFormat = "vtable constructor did not declare schema: %s";
*pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
sqlite3VtabUnlock(pVTable);
rc = SQLITE_ERROR;
}else{
int iCol;
/* If everything went according to plan, link the new VTable structure
** into the linked list headed by pTab->pVTable. Then loop through the
** columns of the table to see if any of them contain the token "hidden".
** If so, set the Column.isHidden flag and remove the token from
** the type string. */
pVTable->pNext = pTab->pVTable;
pTab->pVTable = pVTable;
for(iCol=0; iCol<pTab->nCol; iCol++){
char *zType = pTab->aCol[iCol].zType;
int nType;
int i = 0;
if( !zType ) continue;
nType = sqlite3Strlen30(zType);
if( sqlite3StrNICmp("hidden", zType, 6)||(zType[6] && zType[6]!=' ') ){
for(i=0; i<nType; i++){
if( (0==sqlite3StrNICmp(" hidden", &zType[i], 7))
&& (zType[i+7]=='\0' || zType[i+7]==' ')
){
i++;
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].isHidden = 1;
}
}
}
}
sqlite3DbFree(db, zModuleName);
db->pVTab = 0;
return rc;
}
