ReferenceAble.h

//-*-C++-*-
/***************************************************************************
 *
 *   Copyright (C) 2004 by Willem van Straten
 *   Licensed under the Academic Free License version 2.1
 *
 ***************************************************************************/
 
// psrchive/Util/units/ReferenceAble.h
 
#ifndef __ReferenceAble_h
#define __ReferenceAble_h
 
#include <vector>
#include <string>
 
#include "HeapTracked.h"
 
namespace Reference {

  extern bool verbose;


  class Able : public HeapTracked {
 
    template<class Type, bool active> friend class To;
 
  public:

    Able ();

    Able (const Able&);

    Able& operator = (const Able&);

    virtual ~Able();
    
    unsigned get_reference_count() const { return __reference_count; }

    static size_t get_instance_count ();
 
  protected:

    class Handle;

    Handle* __reference (bool active) const;

    void __dereference (bool auto_delete = true) const;
 
  private:

    mutable Handle* __reference_handle = nullptr;

    mutable unsigned __reference_count = 0;
 
  };

  class Able::Handle {
 
  private:
    Handle (const Handle&);

    Handle& operator = (const Handle&);
 
  public:

    Handle ();

    ~Handle();

    Able* pointer = nullptr;

    unsigned handle_count = 0;

    void decrement (bool active, bool auto_delete);

    static void copy (Handle* &to, Handle* const &from, bool active);
 
  };
 
}
 
#endif // #ifndef __ReferenceAble_h