Function binlog_clone_consistent_snapshot

phx_percona/percona/sql/binlog.cc:1387–1436

}

static int binlog_clone_consistent_snapshot(handlerton *hton, THD *thd,
                                            THD *from_thd)
{
  binlog_cache_mngr *from_cache_mngr;
  binlog_cache_mngr *cache_mngr;
  int err= 0;
  char log_file_name[FN_REFLEN];
  my_off_t pos;

  DBUG_ENTER("binlog_start_consistent_snapshot");

  from_cache_mngr= opt_bin_log ?
    (binlog_cache_mngr *) thd_get_cache_mngr(from_thd) : NULL;

  if (from_cache_mngr == NULL)
  {
    push_warning_printf(thd, Sql_condition::WARN_LEVEL_WARN,
                        HA_ERR_UNSUPPORTED,
                        "WITH CONSISTENT SNAPSHOT FROM SESSION was ignored for "
                        "binary log, because the specified session does not "
                        "have a consistent snapshot of binary log "
                        "coordinates.");
    DBUG_RETURN(0);
  }

  if ((err= thd->binlog_setup_trx_data()))
    DBUG_RETURN(err);

  cache_mngr= thd_get_cache_mngr(thd);

  mysql_mutex_lock(&from_cache_mngr->binlog_info.lock);

  pos= from_cache_mngr->binlog_info.pos;
  strmake(log_file_name, from_cache_mngr->binlog_info.log_file_name,
          sizeof(log_file_name) - 1);

  mysql_mutex_unlock(&from_cache_mngr->binlog_info.lock);

  mysql_mutex_lock(&cache_mngr->binlog_info.lock);

  cache_mngr->binlog_info.pos = pos;
  strmake(cache_mngr->binlog_info.log_file_name, log_file_name,
          sizeof(cache_mngr->binlog_info.log_file_name) - 1);

  mysql_mutex_unlock(&cache_mngr->binlog_info.lock);

  trans_register_ha(thd, TRUE, hton);

  DBUG_RETURN(err);
}

/**
  This function is called once after each statement.