shared_ptr.hpp

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   #else
   shared_ptr & operator=(shared_ptr &&other) // never throws
   {
      this_type(other).swap(*this);
      return *this;
   }
   #endif

   //!This is equivalent to:
   //!this_type().swap(*this);
   void reset()
   {  
      this_type().swap(*this);   
   }

   //!This is equivalent to:
   //!this_type(p, a, d).swap(*this);
   template<class Pointer>
   void reset(const Pointer &p, const VoidAllocator &a = VoidAllocator(), const Deleter &d = Deleter())
   {  
      //Check that the pointer passed is of the same type that
      //the pointer the allocator defines or it's a raw pointer
      typedef typename detail::pointer_to_other<Pointer, T>::type ParameterPointer;
      BOOST_STATIC_ASSERT((detail::is_same<pointer, ParameterPointer>::value) ||
                          (detail::is_pointer<Pointer>::value));
      this_type(p, a, d).swap(*this);  
   }

   template<class Y>
   void reset(shared_ptr<Y, VoidAllocator, Deleter> const & r, const pointer &p)
   {
      this_type(r, p).swap(*this);
   }

   //!Returns a reference to the
   //!pointed type
   reference operator* () const // never throws
   {  BOOST_ASSERT(m_pn.get_pointer() != 0);  return *m_pn.get_pointer(); }

   //!Returns the pointer pointing 
   //!to the owned object
   pointer operator-> () const // never throws
   {  BOOST_ASSERT(m_pn.get_pointer() != 0);  return m_pn.get_pointer();  }

   //!Returns the pointer pointing 
   //!to the owned object
   pointer get() const  // never throws
   {  return m_pn.get_pointer();  }

   /// @cond
   // implicit conversion to "bool"
   void unspecified_bool_type_func() const {}
   typedef void (this_type::*unspecified_bool_type)() const;

   operator unspecified_bool_type() const // never throws
   {  return !m_pn.get_pointer() ? 0 : &this_type::unspecified_bool_type_func;  }
   /// @endcond

   //!Not operator.
   //!Returns true if this->get() != 0, false otherwise
   bool operator! () const // never throws
   {  return !m_pn.get_pointer();   }

   //!Returns use_count() == 1.
   //!unique() might be faster than use_count()
   bool unique() const // never throws
   {  return m_pn.unique();  }

   //!Returns the number of shared_ptr objects, *this included,
   //!that share ownership with *this, or an unspecified nonnegative
   //!value when *this is empty.
   //!use_count() is not necessarily efficient. Use only for
   //!debugging and testing purposes, not for production code.
   long use_count() const // never throws
   {  return m_pn.use_count();  }

   //!Exchanges the contents of the two
   //!smart pointers.
   void swap(shared_ptr<T, VoidAllocator, Deleter> & other) // never throws
   {  m_pn.swap(other.m_pn);   }

   /// @cond

   template<class T2, class A2, class Deleter2> 
   bool _internal_less(shared_ptr<T2, A2, Deleter2> const & rhs) const
   {  return m_pn < rhs.m_pn;  }

   const_deleter_pointer get_deleter() const
   {  return m_pn.get_deleter(); }

//   const_allocator_pointer get_allocator() const
//   {  return m_pn.get_allocator(); }

   private:

   template<class T2, class A2, class Deleter2> friend class shared_ptr;
   template<class T2, class A2, class Deleter2> friend class weak_ptr;

   detail::shared_count<T, VoidAllocator, Deleter>   m_pn;    // reference counter
   /// @endcond
};  // shared_ptr

template<class T, class VoidAllocator, class Deleter, class U, class VoidAllocator2, class Deleter2> inline 
bool operator==(shared_ptr<T, VoidAllocator, Deleter> const & a, shared_ptr<U, VoidAllocator2, Deleter2> const & b)
{  return a.get() == b.get(); }

template<class T, class VoidAllocator, class Deleter, class U, class VoidAllocator2, class Deleter2> inline 
bool operator!=(shared_ptr<T, VoidAllocator, Deleter> const & a, shared_ptr<U, VoidAllocator2, Deleter2> const & b)
{  return a.get() != b.get(); }

template<class T, class VoidAllocator, class Deleter, class U, class VoidAllocator2, class Deleter2> inline 
bool operator<(shared_ptr<T, VoidAllocator, Deleter> const & a, shared_ptr<U, VoidAllocator2, Deleter2> const & b)
{  return a._internal_less(b);   }

template<class T, class VoidAllocator, class Deleter> inline 
void swap(shared_ptr<T, VoidAllocator, Deleter> & a, shared_ptr<T, VoidAllocator, Deleter> & b)
{  a.swap(b);  }

template<class T, class VoidAllocator, class Deleter, class U> inline
shared_ptr<T, VoidAllocator, Deleter> static_pointer_cast(shared_ptr<U, VoidAllocator, Deleter> const & r)
{  return shared_ptr<T, VoidAllocator, Deleter>(r, detail::static_cast_tag());   }

template<class T, class VoidAllocator, class Deleter, class U> inline 
shared_ptr<T, VoidAllocator, Deleter> const_pointer_cast(shared_ptr<U, VoidAllocator, Deleter> const & r)
{  return shared_ptr<T, VoidAllocator, Deleter>(r, detail::const_cast_tag()); }

template<class T, class VoidAllocator, class Deleter, class U> inline 
shared_ptr<T, VoidAllocator, Deleter> dynamic_pointer_cast(shared_ptr<U, VoidAllocator, Deleter> const & r)
{  return shared_ptr<T, VoidAllocator, Deleter>(r, detail::dynamic_cast_tag());  }

// get_pointer() enables boost::mem_fn to recognize shared_ptr
template<class T, class VoidAllocator, class Deleter> inline
T * get_pointer(shared_ptr<T, VoidAllocator, Deleter> const & p)
{  return p.get();   }

// operator<<
template<class E, class T, class Y, class VoidAllocator, class Deleter> inline
std::basic_ostream<E, T> & operator<< 
   (std::basic_ostream<E, T> & os, shared_ptr<Y, VoidAllocator, Deleter> const & p)
{  os << p.get();   return os;   }

//!Returns the type of a shared pointer
//!of type T with the allocator boost::interprocess::allocator allocator
//!and boost::interprocess::deleter deleter
//!that can be constructed in the given managed segment type.
template<class T, class ManagedMemory>
struct managed_shared_ptr
{
   typedef typename ManagedMemory::template allocator<void>::type void_allocator;
   typedef typename ManagedMemory::template deleter<T>::type      deleter;
   typedef shared_ptr< T, void_allocator, deleter>                type;
};

//!Returns an instance of a shared pointer constructed
//!with the default allocator and deleter from a pointer
//!of type T that has been allocated in the passed managed segment
template<class T, class ManagedMemory>
inline typename managed_shared_ptr<T, ManagedMemory>::type
   make_managed_shared_ptr(T *constructed_object, ManagedMemory &managed_memory)
{
   return typename managed_shared_ptr<T, ManagedMemory>::type
   ( constructed_object
   , managed_memory.template get_allocator<void>()
   , managed_memory.template get_deleter<T>()
   );
}


/*
// get_deleter (experimental)
template<class T, class VoidAllocator, class Deleter> 
typename detail::pointer_to_other<shared_ptr<T, VoidAllocator, Deleter>, Deleter>::type
   get_deleter(shared_ptr<T, VoidAllocator, Deleter> const & p)
{  return static_cast<Deleter *>(p._internal_get_deleter(typeid(Deleter)));   }
*/

/// @cond

//!This class has move constructor
template <class T, class VA, class D>
struct is_movable<boost::interprocess::shared_ptr<T, VA, D> >
{
   enum {   value = true };
};

/// @endcond

} // namespace interprocess

/// @cond

#if defined(_MSC_VER) && (_MSC_VER < 1400)
// get_pointer() enables boost::mem_fn to recognize shared_ptr
template<class T, class VoidAllocator, class Deleter> inline
T * get_pointer(boost::interprocess::shared_ptr<T, VoidAllocator, Deleter> const & p)
{  return p.get();   }
#endif

/// @endcond

} // namespace boost

#include <boost/interprocess/detail/config_end.hpp>

#endif  // #ifndef BOOST_INTERPROCESS_SHARED_PTR_HPP_INCLUDED