Function sql_alloc_error_handler

sql/thr_malloc.cc:27–58

extern "C" {
  void sql_alloc_error_handler(void)
  {
    THD *thd= current_thd;
    if (likely(thd))
    {
      if (! thd->is_error())
      {
        /*
          This thread is Out Of Memory.
          An OOM condition is a fatal error.
          It should not be caught by error handlers in stored procedures.
          Also, recording that SQL condition in the condition area could
          cause more memory allocations, which in turn could raise more
          OOM conditions, causing recursion in the error handling code itself.
          As a result, my_error() should not be invoked, and the
          thread diagnostics area is set to an error status directly.
          Note that Diagnostics_area::set_error_status() is safe,
          since it does not call any memory allocation routines.
          The visible result for a client application will be:
          - a query fails with an ER_OUT_OF_RESOURCES error,
          returned in the error packet.
          - SHOW ERROR/SHOW WARNINGS may be empty.
        */
        thd->get_stmt_da()->set_error_status(ER_OUT_OF_RESOURCES);
      }
    }

    /* Skip writing to the error log to avoid mtr complaints */
    DBUG_EXECUTE_IF("simulate_out_of_memory", return;);

    sql_print_error("%s", ER_DEFAULT(ER_OUT_OF_RESOURCES));
  }
}

void init_sql_alloc(PSI_memory_key key, MEM_ROOT *mem_root, uint block_size,