ReferenceCounted.h

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#ifndef ZYPP_BASE_REFERENCECOUNTED_H
#define ZYPP_BASE_REFERENCECOUNTED_H

#include <iosfwd>

#include "zypp/base/PtrTypes.h"

namespace zypp
{ 

  namespace base
  { 

    //
    //  CLASS NAME : ReferenceCounted
    //
    class ReferenceCounted
    {
      friend std::ostream & operator<<( std::ostream & str, const ReferenceCounted & obj );

    public:
      ReferenceCounted();

      ReferenceCounted( const ReferenceCounted & rhs );

      virtual ~ReferenceCounted();

      ReferenceCounted & operator=( const ReferenceCounted & )
      { return *this; }

    public:
      unsigned refCount() const
      { return _counter; }

      void ref() const
      { ref_to( ++_counter ); }

      void unref() const
      {
        if ( !_counter )
          unrefException(); // will throw!
        if ( --_counter )
          unref_to( _counter );
        else
          delete this;
      }

      static void add_ref( const ReferenceCounted * ptr_r )
      { if( ptr_r ) ptr_r->ref(); }

      static void release( const ReferenceCounted * ptr_r )
      { if( ptr_r ) ptr_r->unref(); }

    protected:
      virtual std::ostream & dumpOn( std::ostream & str ) const;

      virtual void ref_to( unsigned /* rep_cnt_r */ ) const {}

      virtual void unref_to( unsigned /* rep_cnt_r */ ) const {}

    private:
      mutable unsigned _counter;

      void unrefException() const;
    };

    inline void intrusive_ptr_add_ref( const ReferenceCounted * ptr_r )
    { ReferenceCounted::add_ref( ptr_r ); }

    inline void intrusive_ptr_release( const ReferenceCounted * ptr_r )
    { ReferenceCounted::release( ptr_r ); }

    inline std::ostream & operator<<( std::ostream & str, const ReferenceCounted & obj )
    { return obj.dumpOn( str ); }

  } // namespace base
} // namespace zypp

#define IMPL_PTR_TYPE(NAME) \
void intrusive_ptr_add_ref( const NAME * ptr_r )               \
{ zypp::base::ReferenceCounted::add_ref( ptr_r ); }                  \
void intrusive_ptr_release( const NAME * ptr_r )               \
{ zypp::base::ReferenceCounted::release( ptr_r ); }

#endif // ZYPP_BASE_REFERENCECOUNTED_H