SQLite

    }
    sqlite3DbFree(db, pColl);
  }
  sqlite3HashClear(&db->aCollSeq);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
    Module *pMod = (Module *)sqliteHashData(i);



    sqlite3VtabEponymousTableClear(db, pMod);
    sqlite3VtabModuleUnref(db, pMod);
  }
  sqlite3HashClear(&db->aModule);
#endif

  sqlite3Error(db, SQLITE_OK); /* Deallocates any cached error strings. */
  sqlite3ValueFree(db->pErr);
  sqlite3CloseExtensions(db);

#endif
  "    --plain                 Show SQL as it is input",
  "    --stmt                  Trace statement execution (SQLITE_TRACE_STMT)",
  "    --profile               Profile statements (SQLITE_TRACE_PROFILE)",
  "    --row                   Trace each row (SQLITE_TRACE_ROW)",
  "    --close                 Trace connection close (SQLITE_TRACE_CLOSE)",
#endif /* SQLITE_OMIT_TRACE */
#ifdef SQLITE_DEBUG
  ".unmodule NAME ...       Unregister virtual table modules",
#endif
  ".vfsinfo ?AUX?           Information about the top-level VFS",
  ".vfslist                 List all available VFSes",
  ".vfsname ?AUX?           Print the name of the VFS stack",
  ".width NUM1 NUM2 ...     Set column widths for \"column\" mode",
  "     Negative values right-justify",
};

      sqlite3_trace_v2(p->db, 0, 0, 0);
    }else{
      if( mType==0 ) mType = SQLITE_TRACE_STMT;
      sqlite3_trace_v2(p->db, mType, sql_trace_callback, p);
    }
  }else
#endif /* !defined(SQLITE_OMIT_TRACE) */

#ifdef SQLITE_DEBUG
  if( c=='u' && strncmp(azArg[0], "unmodule", n)==0 ){
    int ii;
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .unmodule NAME ...\n");
      rc = 1;
      goto meta_command_exit;
    }
    open_db(p, 0);
    for(ii=1; ii<nArg; ii++){
      sqlite3_create_module(p->db, azArg[ii], 0, 0);
    }
  }else
#endif

#if SQLITE_USER_AUTHENTICATION
  if( c=='u' && strncmp(azArg[0], "user", n)==0 ){
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .user SUBCOMMAND ...\n");
      rc = 1;
      goto meta_command_exit;

** is a pointer to a destructor for the pClientData.  ^SQLite will
** invoke the destructor function (if it is not NULL) when SQLite
** no longer needs the pClientData pointer.  ^The destructor will also
** be invoked if the call to sqlite3_create_module_v2() fails.
** ^The sqlite3_create_module()
** interface is equivalent to sqlite3_create_module_v2() with a NULL
** destructor.
**
** ^If the third parameter (the pointer to the sqlite3_module object) is
** NULL then no new module is create and any existing modules with the
** same name are dropped.
*/
int sqlite3_create_module(
  sqlite3 *db,               /* SQLite connection to register module with */
  const char *zName,         /* Name of the module */
  const sqlite3_module *p,   /* Methods for the module */
  void *pClientData          /* Client data for xCreate/xConnect */
);

** Each SQLite module (virtual table definition) is defined by an
** instance of the following structure, stored in the sqlite3.aModule
** hash table.
*/
struct Module {
  const sqlite3_module *pModule;       /* Callback pointers */
  const char *zName;                   /* Name passed to create_module() */
  int nRefModule;                      /* Number of pointers to this object */
  void *pAux;                          /* pAux passed to create_module() */
  void (*xDestroy)(void *);            /* Module destructor function */
  Table *pEpoTab;                      /* Eponymous table for this module */
};

/*
** information about each column of an SQL table is held in an instance

#  define sqlite3VtabClear(Y)
#  define sqlite3VtabSync(X,Y) SQLITE_OK
#  define sqlite3VtabRollback(X)
#  define sqlite3VtabCommit(X)
#  define sqlite3VtabInSync(db) 0
#  define sqlite3VtabLock(X)
#  define sqlite3VtabUnlock(X)
#  define sqlite3VtabModuleUnref(D,X)
#  define sqlite3VtabUnlockList(X)
#  define sqlite3VtabSavepoint(X, Y, Z) SQLITE_OK
#  define sqlite3GetVTable(X,Y)  ((VTable*)0)
#else
   void sqlite3VtabClear(sqlite3 *db, Table*);
   void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
   int sqlite3VtabSync(sqlite3 *db, Vdbe*);
   int sqlite3VtabRollback(sqlite3 *db);
   int sqlite3VtabCommit(sqlite3 *db);
   void sqlite3VtabLock(VTable *);
   void sqlite3VtabUnlock(VTable *);
   void sqlite3VtabModuleUnref(sqlite3*,Module*);
   void sqlite3VtabUnlockList(sqlite3*);
   int sqlite3VtabSavepoint(sqlite3 *, int, int);
   void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
   VTable *sqlite3GetVTable(sqlite3*, Table*);
   Module *sqlite3VtabCreateModule(
     sqlite3*,
     const char*,

  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{
      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;
}

  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);
}

/*
** 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,

  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;
    sqlite3VtabModuleUnref(pVTab->db, pVTab->pMod);
    if( p ){
      p->pModule->xDisconnect(p);
    }
    sqlite3DbFree(db, pVTab);
  }
}

    }
    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{

  set ia4 [sqlite3_intarray_create db ia4]
  db eval {
    SELECT type, name FROM temp.sqlite_master
     ORDER BY name
  }
} {table ia1 table ia2 table ia3 table ia4}

# Verify the ability to DROP and recreate an intarray virtual table.
do_test intarray-1.1b {
  db eval {DROP TABLE ia1}
  set rc [catch {sqlite3_intarray_create db ia1} ia1]
  lappend rc $ia1
} {/0 [0-9A-Z]+/} 

do_test intarray-1.2 {
  db eval {
    SELECT b FROM t1 WHERE a IN ia3 ORDER BY a
  }
} {}

  set echo_module {}
  do_execsql_test 18.$tn.1 $sql $res
  do_test         18.$tn.2 { lrange $::echo_module 2 end } $filter
}
do_execsql_test 18.2.x {  PRAGMA case_sensitive_like = OFF }

#-------------------------------------------------------------------------
# Test that it is ok to override and existing module.
#
do_test 19.1 {
  sqlite3 db2 test.db
  register_echo_module [sqlite3_connection_pointer db2]
} SQLITE_OK
do_test 19.2 {
  register_echo_module [sqlite3_connection_pointer db2]
} SQLITE_OK
do_test 19.3 {
  db2 close
} {}

#-------------------------------------------------------------------------
# Test that the bug fixed by [b0c1ba655d69] really is fixed.
#