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diff --git a/lib/libsqlite3/src/vtab.c b/lib/libsqlite3/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 */
-};
-
-/*
-** 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;
- int nName;
-
- sqlite3_mutex_enter(db->mutex);
- nName = sqlite3Strlen30(zName);
- if( sqlite3HashFind(&db->aModule, zName) ){
- rc = SQLITE_MISUSE_BKPT;
- }else{
- Module *pMod;
- pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
- if( pMod ){
- Module *pDel;
- char *zCopy = (char *)(&pMod[1]);
- memcpy(zCopy, zName, nName+1);
- pMod->zName = zCopy;
- pMod->pModule = pModule;
- pMod->pAux = pAux;
- pMod->xDestroy = xDestroy;
- pMod->pEpoTab = 0;
- pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod);
- assert( pDel==0 || pDel==pMod );
- if( pDel ){
- db->mallocFailed = 1;
- sqlite3DbFree(db, pDel);
- }
- }
- }
- 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);
-}
-
-/*
-** 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->pVTable; 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->magic==SQLITE_MAGIC_OPEN || db->magic==SQLITE_MAGIC_ZOMBIE );
-
- pVTab->nRef--;
- if( pVTab->nRef==0 ){
- sqlite3_vtab *p = pVTab->pVtab;
- if( p ){
- p->pModule->xDisconnect(p);
- }
- sqlite3DbFree(db, pVTab);
- }
-}
-
-/*
-** Table p is a virtual table. This function moves all elements in the
-** p->pVTable 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->pVTable list.
-*/
-static VTable *vtabDisconnectAll(sqlite3 *db, Table *p){
- VTable *pRet = 0;
- VTable *pVTable = p->pVTable;
- p->pVTable = 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->pVTable 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->pVTable = 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->pVTable; *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;
- 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 );
- }
-}
-
-/*
-** 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){
- if( !db || db->pnBytesFreed==0 ) vtabDisconnectAll(0, p);
- if( p->azModuleArg ){
- int i;
- for(i=0; i<p->nModuleArg; i++){
- if( i!=1 ) sqlite3DbFree(db, p->azModuleArg[i]);
- }
- sqlite3DbFree(db, p->azModuleArg);
- }
-}
-
-/*
-** Add a new module argument to pTable->azModuleArg[].
-** The string is not copied - the pointer is stored. The
-** string will be freed automatically when the table is
-** deleted.
-*/
-static void addModuleArgument(sqlite3 *db, Table *pTable, char *zArg){
- int nBytes = sizeof(char *)*(2+pTable->nModuleArg);
- char **azModuleArg;
- azModuleArg = sqlite3DbRealloc(db, pTable->azModuleArg, nBytes);
- if( azModuleArg==0 ){
- sqlite3DbFree(db, zArg);
- }else{
- int i = pTable->nModuleArg++;
- azModuleArg[i] = zArg;
- azModuleArg[i+1] = 0;
- pTable->azModuleArg = 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 */
-){
- int iDb; /* The database the table is being created in */
- 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 );
-
- db = pParse->db;
- iDb = sqlite3SchemaToIndex(db, pTable->pSchema);
- assert( iDb>=0 );
-
- pTable->tabFlags |= TF_Virtual;
- pTable->nModuleArg = 0;
- addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
- addModuleArgument(db, pTable, 0);
- addModuleArgument(db, 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_master table, has already been made by sqlite3StartTable().
- ** The second call, to obtain permission to create the table, is made now.
- */
- if( pTable->azModuleArg ){
- sqlite3AuthCheck(pParse, SQLITE_CREATE_VTABLE, pTable->zName,
- pTable->azModuleArg[0], pParse->db->aDb[iDb].zName);
- }
-#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(db, 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;
- addArgumentToVtab(pParse);
- pParse->sArg.z = 0;
- if( pTab->nModuleArg<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_master) then
- ** do additional initialization work and store the statement text
- ** in the sqlite_master table.
- */
- if( !db->init.busy ){
- char *zStmt;
- char *zWhere;
- int iDb;
- int iReg;
- Vdbe *v;
-
- /* 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
- ** SQLITE_MASTER 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_master table tht was created for this vtab
- ** by sqlite3StartTable().
- */
- iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
- sqlite3NestedParse(pParse,
- "UPDATE %Q.%s "
- "SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
- "WHERE rowid=#%d",
- db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
- pTab->zName,
- pTab->zName,
- zStmt,
- pParse->regRowid
- );
- sqlite3DbFree(db, zStmt);
- v = sqlite3GetVdbe(pParse);
- sqlite3ChangeCookie(pParse, iDb);
-
- sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
- zWhere = sqlite3MPrintf(db, "name='%q' AND type='table'", pTab->zName);
- sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere);
-
- iReg = ++pParse->nMem;
- sqlite3VdbeLoadString(v, iReg, pTab->zName);
- sqlite3VdbeAddOp2(v, OP_VCreate, iDb, iReg);
- }
-
- /* If we are rereading the sqlite_master table create the in-memory
- ** record of the table. The xConnect() method is not called until
- ** the first time the virtual table is used in an SQL statement. This
- ** allows a schema that contains virtual tables to be loaded before
- ** the required virtual table implementations are registered. */
- else {
- Table *pOld;
- Schema *pSchema = pTab->pSchema;
- const char *zName = pTab->zName;
- assert( sqlite3SchemaMutexHeld(db, 0, pSchema) );
- pOld = sqlite3HashInsert(&pSchema->tblHash, zName, pTab);
- if( pOld ){
- db->mallocFailed = 1;
- 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 = (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;
- }
-
- pVTable = sqlite3DbMallocZero(db, sizeof(VTable));
- if( !pVTable ){
- sqlite3DbFree(db, zModuleName);
- return SQLITE_NOMEM;
- }
- pVTable->db = db;
- pVTable->pMod = pMod;
-
- iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
- pTab->azModuleArg[1] = db->aDb[iDb].zName;
-
- /* 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 ) db->mallocFailed = 1;
- 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 = pTab->aCol[iCol].zType;
- int nType;
- int i = 0;
- if( !zType ){
- pTab->tabFlags |= oooHidden;
- 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].colFlags |= COLFLAG_HIDDEN;
- 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 );
- if( (pTab->tabFlags & TF_Virtual)==0 || sqlite3GetVTable(db, pTab) ){
- return SQLITE_OK;
- }
-
- /* Locate the required virtual table module */
- zMod = pTab->azModuleArg[0];
- pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);
-
- if( !pMod ){
- const char *zModule = pTab->azModuleArg[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);
- }
- 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;
- int nBytes = sizeof(sqlite3_vtab *) * (db->nVTrans + ARRAY_INCR);
- aVTrans = sqlite3DbRealloc(db, (void *)db->aVTrans, nBytes);
- if( !aVTrans ){
- return SQLITE_NOMEM;
- }
- 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 an 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].zName);
- assert( pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVTable );
-
- /* Locate the required virtual table module */
- zMod = pTab->azModuleArg[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;
- Parse *pParse;
- int rc = SQLITE_OK;
- Table *pTab;
- char *zErr = 0;
-
-#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);
- sqlite3_mutex_leave(db->mutex);
- return SQLITE_MISUSE_BKPT;
- }
- pTab = pCtx->pTab;
- assert( (pTab->tabFlags & TF_Virtual)!=0 );
-
- pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
- if( pParse==0 ){
- rc = SQLITE_NOMEM;
- }else{
- pParse->declareVtab = 1;
- pParse->db = db;
- pParse->nQueryLoop = 1;
-
- if( SQLITE_OK==sqlite3RunParser(pParse, zCreateTable, &zErr)
- && pParse->pNewTable
- && !db->mallocFailed
- && !pParse->pNewTable->pSelect
- && (pParse->pNewTable->tabFlags & TF_Virtual)==0
- ){
- if( !pTab->aCol ){
- pTab->aCol = pParse->pNewTable->aCol;
- pTab->nCol = pParse->pNewTable->nCol;
- pParse->pNewTable->nCol = 0;
- pParse->pNewTable->aCol = 0;
- }
- pCtx->bDeclared = 1;
- }else{
- sqlite3ErrorWithMsg(db, SQLITE_ERROR, (zErr ? "%s" : 0), zErr);
- sqlite3DbFree(db, zErr);
- rc = SQLITE_ERROR;
- }
- pParse->declareVtab = 0;
-
- if( pParse->pVdbe ){
- sqlite3VdbeFinalize(pParse->pVdbe);
- }
- sqlite3DeleteTable(db, pParse->pNewTable);
- sqlite3ParserReset(pParse);
- sqlite3StackFree(db, pParse);
- }
-
- 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].zName);
- if( ALWAYS(pTab!=0 && pTab->pVTable!=0) ){
- VTable *p;
- int (*xDestroy)(sqlite3_vtab *);
- for(p=pTab->pVTable; p; p=p->pNext){
- assert( p->pVtab );
- if( p->pVtab->nRef>0 ){
- return SQLITE_LOCKED;
- }
- }
- p = vtabDisconnectAll(db, pTab);
- xDestroy = p->pMod->pModule->xDestroy;
- assert( xDestroy!=0 ); /* Checked before the virtual table is created */
- rc = 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;
-}
-
-/*
-** 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 ) rc = sqlite3VtabSavepoint(db, SAVEPOINT_BEGIN, 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);
- 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 ){
- rc = xMethod(pVTab->pVtab, iSavepoint);
- }
- }
- }
- }
- 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 (*xFunc)(sqlite3_context*,int,sqlite3_value**) = 0;
- void *pArg = 0;
- FuncDef *pNew;
- int rc = 0;
- char *zLowerName;
- unsigned char *z;
-
-
- /* 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;
- pTab = pExpr->pTab;
- if( NEVER(pTab==0) ) return pDef;
- if( (pTab->tabFlags & TF_Virtual)==0 ) 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
- */
- zLowerName = sqlite3DbStrDup(db, pDef->zName);
- if( zLowerName ){
- for(z=(unsigned char*)zLowerName; *z; z++){
- *z = sqlite3UpperToLower[*z];
- }
- rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xFunc, &pArg);
- sqlite3DbFree(db, zLowerName);
- }
- 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 = (char *)&pNew[1];
- memcpy(pNew->zName, pDef->zName, sqlite3Strlen30(pDef->zName)+1);
- pNew->xFunc = xFunc;
- 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 = sqlite3_realloc64(pToplevel->apVtabLock, n);
- if( apVtabLock ){
- pToplevel->apVtabLock = apVtabLock;
- pToplevel->apVtabLock[pToplevel->nVtabLock++] = pTab;
- }else{
- pToplevel->db->mallocFailed = 1;
- }
-}
-
-/*
-** Check to see if virtual tale 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 the eponymous virtual table instance exists
-** when this routine returns, and return zero if it does not exist.
-**
-** 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 existance. 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 nName;
- int rc;
- sqlite3 *db = pParse->db;
- if( pMod->pEpoTab ) return 1;
- if( pModule->xCreate!=0 && pModule->xCreate!=pModule->xConnect ) return 0;
- nName = sqlite3Strlen30(pMod->zName) + 1;
- pTab = sqlite3DbMallocZero(db, sizeof(Table) + nName);
- if( pTab==0 ) return 0;
- pMod->pEpoTab = pTab;
- pTab->zName = (char*)&pTab[1];
- memcpy(pTab->zName, pMod->zName, nName);
- pTab->nRef = 1;
- pTab->pSchema = db->aDb[0].pSchema;
- pTab->tabFlags |= TF_Virtual;
- pTab->nModuleArg = 0;
- pTab->iPKey = -1;
- addModuleArgument(db, pTab, sqlite3DbStrDup(db, pTab->zName));
- addModuleArgument(db, pTab, 0);
- addModuleArgument(db, 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 0;
- }
- 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 ){
- sqlite3DeleteColumnNames(db, pTab);
- sqlite3VtabClear(db, pTab);
- sqlite3DbFree(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;
-
-#ifdef SQLITE_ENABLE_API_ARMOR
- if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
-#endif
- sqlite3_mutex_enter(db->mutex);
- va_start(ap, op);
- switch( op ){
- case SQLITE_VTAB_CONSTRAINT_SUPPORT: {
- VtabCtx *p = db->pVtabCtx;
- if( !p ){
- rc = SQLITE_MISUSE_BKPT;
- }else{
- assert( p->pTab==0 || (p->pTab->tabFlags & TF_Virtual)!=0 );
- p->pVTable->bConstraint = (u8)va_arg(ap, int);
- }
- 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 */
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.