Move bundled copy of sqlite one level deeper to better separate it...

third_party/sqlite/src/vtab.c

Index: third_party/sqlite/src/vtab.c
===================================================================
--- third_party/sqlite/src/vtab.c	(revision 56608)
+++ third_party/sqlite/src/vtab.c	(working copy)
@@ -1,962 +0,0 @@
-/*
-** 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.
-**
-** $Id: vtab.c,v 1.94 2009/08/08 18:01:08 drh Exp $
-*/
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-#include "sqliteInt.h"
-
-/*
-** 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, nName;
-  Module *pMod;
-
-  sqlite3_mutex_enter(db->mutex);
-  nName = sqlite3Strlen30(zName);
-  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;
-    pDel = (Module *)sqlite3HashInsert(&db->aModule, zCopy, nName, (void*)pMod);
-    if( pDel && pDel->xDestroy ){
-      pDel->xDestroy(pDel->pAux);
-    }
-    sqlite3DbFree(db, pDel);
-    if( pDel==pMod ){
-      db->mallocFailed = 1;
-    }
-    sqlite3ResetInternalSchema(db, 0);
-  }else if( xDestroy ){
-    xDestroy(pAux);
-  }
-  rc = sqlite3ApiExit(db, SQLITE_OK);
-  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 */
-){
-  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 */
-){
-  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( sqlite3SafetyCheckOk(db) );
-
-  pVTab->nRef--;
-  if( pVTab->nRef==0 ){
-    sqlite3_vtab *p = pVTab->pVtab;
-    if( p ){
-#ifdef SQLITE_DEBUG
-      if( pVTab->db->magic==SQLITE_MAGIC_BUSY ){
-        (void)sqlite3SafetyOff(db);
-        p->pModule->xDisconnect(p);
-        (void)sqlite3SafetyOn(db);
-      } else
-#endif
-      {
-        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 ||
-    sqlite3BtreeHoldsMutex(db->aDb[sqlite3SchemaToIndex(db, p->pSchema)].pBt) 
-  );
-
-  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;
-}
-
-
-/*
-** 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(Table *p){
-  vtabDisconnectAll(0, p);
-  if( p->azModuleArg ){
-    int i;
-    for(i=0; i<p->nModuleArg; i++){
-      sqlite3DbFree(p->dbMem, p->azModuleArg[i]);
-    }
-    sqlite3DbFree(p->dbMem, 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 i = pTable->nModuleArg++;
-  int nBytes = sizeof(char *)*(1+pTable->nModuleArg);
-  char **azModuleArg;
-  azModuleArg = sqlite3DbRealloc(db, pTable->azModuleArg, nBytes);
-  if( azModuleArg==0 ){
-    int j;
-    for(j=0; j<i; j++){
-      sqlite3DbFree(db, pTable->azModuleArg[j]);
-    }
-    sqlite3DbFree(db, zArg);
-    sqlite3DbFree(db, pTable->azModuleArg);
-    pTable->nModuleArg = 0;
-  }else{
-    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 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, 0);
-  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, sqlite3DbStrDup(db, db->aDb[iDb].zName));
-  addModuleArgument(db, pTable, sqlite3DbStrDup(db, pTable->zName));
-  pParse->sNameToken.n = (int)(&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
-}
-
-/*
-** 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 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;
-    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'", pTab->zName);
-    sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 1, 0, zWhere, P4_DYNAMIC);
-    sqlite3VdbeAddOp4(v, OP_VCreate, iDb, 0, 0, 
-                         pTab->zName, sqlite3Strlen30(pTab->zName) + 1);
-  }
-
-  /* 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;
-    int nName = sqlite3Strlen30(zName);
-    pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
-    if( pOld ){
-      db->mallocFailed = 1;
-      assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
-      return;
-    }
-    pSchema->db = pParse->db;
-    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
-){
-  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 */
-  (void)sqlite3SafetyOff(db);
-  rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
-  (void)sqlite3SafetyOn(db);
-  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;
-}
-
-/*
-** 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, sqlite3Strlen30(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;
-}
-
-/*
-** Add the virtual table pVTab to the array sqlite3.aVTrans[].
-*/
-static int addToVTrans(sqlite3 *db, VTable *pVTab){
-  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;
-  }
-
-  /* Add pVtab to the end of sqlite3.aVTrans */
-  db->aVTrans[db->nVTrans++] = pVTab;
-  sqlite3VtabLock(pVTab);
-  return SQLITE_OK;
-}
-
-/*
-** 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, sqlite3Strlen30(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 ){
-    *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 = 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){
-  Parse *pParse;
-
-  int rc = SQLITE_OK;
-  Table *pTab;
-  char *zErr = 0;
-
-  sqlite3_mutex_enter(db->mutex);
-  pTab = db->pVTab;
-  if( !pTab ){
-    sqlite3Error(db, SQLITE_MISUSE, 0);
-    sqlite3_mutex_leave(db->mutex);
-    return SQLITE_MISUSE;
-  }
-  assert( (pTab->tabFlags & TF_Virtual)!=0 );
-
-  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
-  if( pParse==0 ){
-    rc = SQLITE_NOMEM;
-  }else{
-    pParse->declareVtab = 1;
-    pParse->db = db;
-  
-    if( 
-        SQLITE_OK == sqlite3RunParser(pParse, zCreateTable, &zErr) && 
-        pParse->pNewTable && 
-        !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;
-      }
-      db->pVTab = 0;
-    } else {
-      sqlite3Error(db, SQLITE_ERROR, zErr);
-      sqlite3DbFree(db, zErr);
-      rc = SQLITE_ERROR;
-    }
-    pParse->declareVtab = 0;
-  
-    if( pParse->pVdbe ){
-      sqlite3VdbeFinalize(pParse->pVdbe);
-    }
-    sqlite3DeleteTable(pParse->pNewTable);
-    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 = vtabDisconnectAll(db, pTab);
-
-    rc = sqlite3SafetyOff(db);
-    assert( rc==SQLITE_OK );
-    rc = p->pMod->pModule->xDestroy(p->pVtab);
-    (void)sqlite3SafetyOn(db);
-
-    /* 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 ){
-    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;
-  }
-}
-
-/*
-** 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.
-**
-** Set *pzErrmsg to point to a buffer that should be released using 
-** sqlite3DbFree() containing an error message, if one is available.
-*/
-int sqlite3VtabSync(sqlite3 *db, char **pzErrmsg){
-  int i;
-  int rc = SQLITE_OK;
-  int rcsafety;
-  VTable **aVTrans = db->aVTrans;
-
-  rc = sqlite3SafetyOff(db);
-  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);
-      sqlite3DbFree(db, *pzErrmsg);
-      *pzErrmsg = pVtab->zErrMsg;
-      pVtab->zErrMsg = 0;
-    }
-  }
-  db->aVTrans = aVTrans;
-  rcsafety = sqlite3SafetyOn(db);
-
-  if( rc==SQLITE_OK ){
-    rc = rcsafety;
-  }
-  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 */
-    rc = pModule->xBegin(pVTab->pVtab);
-    if( rc==SQLITE_OK ){
-      rc = addToVTrans(db, 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 (*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->flags |= 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_realloc(pToplevel->apVtabLock, n);
-  if( apVtabLock ){
-    pToplevel->apVtabLock = apVtabLock;
-    pToplevel->apVtabLock[pToplevel->nVtabLock++] = pTab;
-  }else{
-    pToplevel->db->mallocFailed = 1;
-  }
-}
-
-#endif /* SQLITE_OMIT_VIRTUALTABLE */