/*
** 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 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 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->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;
}
/*
** 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;
addModuleArgument(pParse->pNewTable, sqliteStrNDup(z, n));
}
}
/*
** 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 && ALWAYS(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 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].zDbSName);
}
#endif
}
/*
** 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 iDb; /* The database the table is being created in */
Table *pTable; /* The new virtual table */
#ifndef SQLITE_OMIT_SHARED_CACHE
if( sqlite3ThreadDataReadOnly()->useSharedData ){
sqlite3ErrorMsg(pParse, "Cannot use virtual tables in shared-cache mode");
return;
}
#endif
sqlite3StartTable(pParse, pName1, pName2, 0, 0, 1, 0);
pTable = pParse->pNewTable;
if( pTable==0 || pParse->nErr ) return;
assert( 0==pTable->pIndex );
iDb = sqlite3SchemaToIndex(pParse->db, pTable->pSchema);
assert( iDb>=0 );
pTable->isVirtual = 1;
pTable->nModuleArg = 0;
addModuleArgument(pTable, sqlite3NameFromToken(pModuleName));
addModuleArgument(pTable, sqlite3StrDup(pParse->db->aDb[iDb].zName));
addModuleArgument(pTable, sqlite3StrDup(pTable->zName));
pParse->sNameToken.n = pModuleName->z + pModuleName->n - pName1->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
}
