Function mysql_create_function

sql/sql_udf.cc:522–656

*/

int mysql_create_function(THD *thd,udf_func *udf)
{
  int error;
  void *dl=0;
  bool new_dl=0;
  TABLE *table;
  TABLE_LIST tables;
  udf_func *u_d;
  DBUG_ENTER("mysql_create_function");

  if (!initialized)
  {
    if (opt_noacl)
      my_error(ER_CANT_INITIALIZE_UDF, MYF(0),
               udf->name.str,
               "UDFs are unavailable with the --skip-grant-tables option");
    else
      my_message(ER_OUT_OF_RESOURCES, ER_THD(thd, ER_OUT_OF_RESOURCES),
                 MYF(0));
    DBUG_RETURN(1);
  }

  /*
    Ensure that the .dll doesn't have a path
    This is done to ensure that only approved dll from the system
    directories are used (to make this even remotely secure).
  */
  if (check_valid_path(udf->dl, strlen(udf->dl)))
  {
    my_message(ER_UDF_NO_PATHS, ER_THD(thd, ER_UDF_NO_PATHS), MYF(0));
    DBUG_RETURN(1);
  }
  if (check_ident_length(&udf->name))
    DBUG_RETURN(1);

  table= open_udf_func_table(thd);

  mysql_rwlock_wrlock(&THR_LOCK_udf);
  DEBUG_SYNC(current_thd, "mysql_create_function_after_lock");
  if ((u_d= (udf_func*) my_hash_search(&udf_hash, (uchar*) udf->name.str,
                                                  udf->name.length)))
  {
    if (thd->lex->create_info.or_replace())
    {
      if (unlikely((error= mysql_drop_function_internal(thd, u_d, table))))
        goto err;
    }
    else if (thd->lex->create_info.if_not_exists())
    {
      push_warning_printf(thd, Sql_condition::WARN_LEVEL_NOTE, ER_UDF_EXISTS,
                          ER_THD(thd, ER_UDF_EXISTS), udf->name.str);

      goto done;
    }
    else
    {
      my_error(ER_UDF_EXISTS, MYF(0), udf->name.str);
      goto err;