EST_Handleable.h

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#ifndef __EST_HANDLABLE_H__
#define __EST_HANDLABLE_H__

#include <climits>

/** @class EST_Handleable
  * @ingroup supportclasses
  * @brief Reference Counting Interface.
  * 
  * This simple class does most of the things an object which is to be
  * manipulated by EST_THandle style smart pointers needs to provide.
  * 
  * @see EST_THandle
  * @see EST_TBox
  * @see EST_TrackMap
  * @author Richard Caley <rjc@cstr.ed.ac.uk>
  * @version $Id: EST_Handleable.h,v 1.4 2004/09/29 08:24:17 robert Exp $
  */
class EST_Handleable
{
private:
  int p_refcount;

public:
#   define NOT_REFCOUNTED (INT_MAX) 

  EST_Handleable(void) { p_refcount=NOT_REFCOUNTED; }

  int refcount(void) const { return p_refcount;}

  void start_refcounting(int initial=0) {p_refcount=initial;}
  void inc_refcount(void) {if (p_refcount!=NOT_REFCOUNTED) p_refcount++;}
  void dec_refcount(void) {if (p_refcount!=NOT_REFCOUNTED) p_refcount--;}

  int is_unreferenced(void) const {return p_refcount == 0;}
  int is_refcounted(void) const {return p_refcount!= NOT_REFCOUNTED;}
  //@}
};

#endif