text: 
  /****************************************************************************
   *  Copyright (C) 2019 RoboMaster.
   *
   *  This program is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of 
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program. If not, see <http://www.gnu.org/licenses/>.
   ***************************************************************************/
  
  #ifndef __ERRNO_H__
  #define __ERRNO_H__
  
  #ifdef ERRNO_H_GLOBAL
    #define ERRNO_H_EXTERN 
  #else
    #define ERRNO_H_EXTERN extern
  #endif
  
  #ifndef NULL
    #define NULL ((void *)0)
  #endif
  
  #ifndef RM_OK
  #define  RM_OK              0
  #endif
  
  #define RM_ERROR             1
  #define RM_INVAL             2  
  #define RM_EXISTED           3  
  #define RM_UNREGISTERED      4 
  #define RM_NOSTATE           5
  #define RM_USED              6
  #define RM_NOMEM             7
  
  #endif // __ERRNO_H__
  