Function reset_slave

sql/sql_repl.cc:4158–4263

*/

int reset_slave(THD *thd, Master_info* mi)
{
  MY_STAT stat_area;
  char fname[FN_REFLEN];
  int thread_mask= 0, error= 0;
  uint sql_errno=ER_UNKNOWN_ERROR;
  const char* errmsg= "Unknown error occurred while resetting slave";
  char master_info_file_tmp[FN_REFLEN];
  char relay_log_info_file_tmp[FN_REFLEN];
  DBUG_ENTER("reset_slave");

  mi->lock_slave_threads();
  if (mi->killed)
  {
    /* connection was deleted while we waited for lock_slave_threads */
    mi->unlock_slave_threads();
    my_error(WARN_NO_MASTER_INFO, MYF(0), (int) mi->connection_name.length,
             mi->connection_name.str);
    DBUG_RETURN(-1);
  }

  init_thread_mask(&thread_mask,mi,0 /* not inverse */);
  if (thread_mask) // We refuse if any slave thread is running
  {
    mi->unlock_slave_threads();
    my_error(ER_SLAVE_MUST_STOP, MYF(0), (int) mi->connection_name.length,
             mi->connection_name.str);
    DBUG_RETURN(ER_SLAVE_MUST_STOP);
  }

  // delete relay logs, clear relay log coordinates
  if (unlikely((error= purge_relay_logs(&mi->rli, thd,
			       1 /* just reset */,
                                        &errmsg))))
  {
    sql_errno= ER_RELAY_LOG_FAIL;
    goto err;
  }

  if (mi->using_gtid != Master_info::USE_GTID_SLAVE_POS &&
      mi->master_supports_gtid)
  {
    push_warning_printf(
        thd, Sql_condition::WARN_LEVEL_NOTE, WARN_OPTION_CHANGING,
        ER_THD(thd, WARN_OPTION_CHANGING), "RESET SLAVE", "Using_Gtid",
        mi->using_gtid_astext(mi->using_gtid),
        mi->using_gtid_astext(Master_info::USE_GTID_SLAVE_POS));
  }

  /* Clear master's log coordinates and associated information */
  mi->clear_in_memory_info(thd->lex->reset_slave_info.all);

  /*
     Reset errors (the idea is that we forget about the
     old master).
  */
  mi->clear_error();
  mi->rli.clear_error();