Function find_sys_var

sql/sql_plugin.cc:2976–3002

****************************************************************************/

sys_var *find_sys_var(THD *thd, const char *str, size_t length,
                      bool throw_error, bool hash_already_locked)
{
  sys_var *var;
  sys_var_pluginvar *pi;
  DBUG_ENTER("find_sys_var");
  DBUG_PRINT("enter", ("var '%.*s'", (int)length, str));

  if (!hash_already_locked)
    mysql_prlock_rdlock(&LOCK_system_variables_hash);
  if ((var= intern_find_sys_var(str, length)) &&
      (pi= var->cast_pluginvar()))
  {
    mysql_mutex_lock(&LOCK_plugin);
    if (!intern_plugin_lock(thd ? thd->lex : 0, plugin_int_to_ref(pi->plugin),
                            PLUGIN_IS_READY))
      var= NULL; /* failed to lock it, it must be uninstalling */
    mysql_mutex_unlock(&LOCK_plugin);
  }
  if (!hash_already_locked)
    mysql_prlock_unlock(&LOCK_system_variables_hash);

  if (unlikely(!throw_error && !var))
    my_error(ER_UNKNOWN_SYSTEM_VARIABLE, MYF(0),
             (int) (length ? length : strlen(str)), (char*) str);
  DBUG_RETURN(var);
}


/*