boost/interprocess/smart_ptr/intrusive_ptr.hpp
//////////////////////////////////////////////////////////////////////////////
//
// This file is the adaptation for Interprocess of boost/intrusive_ptr.hpp
//
// (C) Copyright Peter Dimov 2001, 2002
// (C) Copyright Ion Gaztanaga 2006-2012. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// See http://www.boost.org/libs/interprocess for documentation.
//
//////////////////////////////////////////////////////////////////////////////
#ifndef BOOST_INTERPROCESS_INTRUSIVE_PTR_HPP_INCLUDED
#define BOOST_INTERPROCESS_INTRUSIVE_PTR_HPP_INCLUDED
//!\file
//!Describes an intrusive ownership pointer.
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/assert.hpp>
#include <boost/interprocess/detail/utilities.hpp>
#include <boost/intrusive/pointer_traits.hpp>
#include <functional> // for std::less
#include <iosfwd> // for std::basic_ostream
namespace boost {
namespace interprocess {
//!The intrusive_ptr class template stores a pointer to an object
//!with an embedded reference count. intrusive_ptr is parameterized on
//!T (the type of the object pointed to) and VoidPointer(a void pointer type
//!that defines the type of pointer that intrusive_ptr will store).
//!intrusive_ptr<T, void *> defines a class with a T* member whereas
//!intrusive_ptr<T, offset_ptr<void> > defines a class with a offset_ptr<T> member.
//!Relies on unqualified calls to:
//!
//! void intrusive_ptr_add_ref(T * p);
//! void intrusive_ptr_release(T * p);
//!
//! with (p != 0)
//!
//!The object is responsible for destroying itself.
template<class T, class VoidPointer>
class intrusive_ptr
{
public:
//!Provides the type of the internal stored pointer.
typedef typename boost::intrusive::
pointer_traits<VoidPointer>::template
rebind_pointer<T>::type pointer;
//!Provides the type of the stored pointer.
typedef T element_type;
/// @cond
private:
typedef VoidPointer VP;
typedef intrusive_ptr this_type;
typedef pointer this_type::*unspecified_bool_type;
/// @endcond
public:
//!Constructor. Initializes internal pointer to 0.
//!Does not throw
intrusive_ptr(): m_ptr(0)
{}
//!Constructor. Copies pointer and if "p" is not zero and
//!"add_ref" is true calls intrusive_ptr_add_ref(to_raw_pointer(p)).
//!Does not throw
intrusive_ptr(const pointer &p, bool add_ref = true): m_ptr(p)
{
if(m_ptr != 0 && add_ref) intrusive_ptr_add_ref(ipcdetail::to_raw_pointer(m_ptr));
}
//!Copy constructor. Copies the internal pointer and if "p" is not
//!zero calls intrusive_ptr_add_ref(to_raw_pointer(p)). Does not throw
intrusive_ptr(intrusive_ptr const & rhs)
: m_ptr(rhs.m_ptr)
{
if(m_ptr != 0) intrusive_ptr_add_ref(ipcdetail::to_raw_pointer(m_ptr));
}
//!Constructor from related. Copies the internal pointer and if "p" is not
//!zero calls intrusive_ptr_add_ref(to_raw_pointer(p)). Does not throw
template<class U> intrusive_ptr
(intrusive_ptr<U, VP> const & rhs)
: m_ptr(rhs.get())
{
if(m_ptr != 0) intrusive_ptr_add_ref(ipcdetail::to_raw_pointer(m_ptr));
}
//!Destructor. If internal pointer is not 0, calls
//!intrusive_ptr_release(to_raw_pointer(m_ptr)). Does not throw
~intrusive_ptr()
{
if(m_ptr != 0) intrusive_ptr_release(ipcdetail::to_raw_pointer(m_ptr));
}
//!Assignment operator. Equivalent to intrusive_ptr(r).swap(*this).
//!Does not throw
intrusive_ptr & operator=(intrusive_ptr const & rhs)
{
this_type(rhs).swap(*this);
return *this;
}
//!Assignment from related. Equivalent to intrusive_ptr(r).swap(*this).
//!Does not throw
template<class U> intrusive_ptr & operator=
(intrusive_ptr<U, VP> const & rhs)
{
this_type(rhs).swap(*this);
return *this;
}
//!Assignment from pointer. Equivalent to intrusive_ptr(r).swap(*this).
//!Does not throw
intrusive_ptr & operator=(pointer rhs)
{
this_type(rhs).swap(*this);
return *this;
}
//!Returns a reference to the internal pointer.
//!Does not throw
pointer &get()
{ return m_ptr; }
//!Returns a reference to the internal pointer.
//!Does not throw
const pointer &get() const
{ return m_ptr; }
//!Returns *get().
//!Does not throw
T & operator*() const
{ return *m_ptr; }
//!Returns *get().
//!Does not throw
const pointer &operator->() const
{ return m_ptr; }
//!Returns get().
//!Does not throw
pointer &operator->()
{ return m_ptr; }
//!Conversion to boolean.
//!Does not throw
operator unspecified_bool_type () const
{ return m_ptr == 0? 0: &this_type::m_ptr; }
//!Not operator.
//!Does not throw
bool operator! () const
{ return m_ptr == 0; }
//!Exchanges the contents of the two smart pointers.
//!Does not throw
void swap(intrusive_ptr & rhs)
{ ipcdetail::do_swap(m_ptr, rhs.m_ptr); }
/// @cond
private:
pointer m_ptr;
/// @endcond
};
//!Returns a.get() == b.get().
//!Does not throw
template<class T, class U, class VP> inline
bool operator==(intrusive_ptr<T, VP> const & a,
intrusive_ptr<U, VP> const & b)
{ return a.get() == b.get(); }
//!Returns a.get() != b.get().
//!Does not throw
template<class T, class U, class VP> inline
bool operator!=(intrusive_ptr<T, VP> const & a,
intrusive_ptr<U, VP> const & b)
{ return a.get() != b.get(); }
//!Returns a.get() == b.
//!Does not throw
template<class T, class VP> inline
bool operator==(intrusive_ptr<T, VP> const & a,
const typename intrusive_ptr<T, VP>::pointer &b)
{ return a.get() == b; }
//!Returns a.get() != b.
//!Does not throw
template<class T, class VP> inline
bool operator!=(intrusive_ptr<T, VP> const & a,
const typename intrusive_ptr<T, VP>::pointer &b)
{ return a.get() != b; }
//!Returns a == b.get().
//!Does not throw
template<class T, class VP> inline
bool operator==(const typename intrusive_ptr<T, VP>::pointer &a,
intrusive_ptr<T, VP> const & b)
{ return a == b.get(); }
//!Returns a != b.get().
//!Does not throw
template<class T, class VP> inline
bool operator!=(const typename intrusive_ptr<T, VP>::pointer &a,
intrusive_ptr<T, VP> const & b)
{ return a != b.get(); }
//!Returns a.get() < b.get().
//!Does not throw
template<class T, class VP> inline
bool operator<(intrusive_ptr<T, VP> const & a,
intrusive_ptr<T, VP> const & b)
{
return std::less<typename intrusive_ptr<T, VP>::pointer>()
(a.get(), b.get());
}
//!Exchanges the contents of the two intrusive_ptrs.
//!Does not throw
template<class T, class VP> inline
void swap(intrusive_ptr<T, VP> & lhs,
intrusive_ptr<T, VP> & rhs)
{ lhs.swap(rhs); }
// operator<<
template<class E, class T, class Y, class VP>
inline std::basic_ostream<E, T> & operator<<
(std::basic_ostream<E, T> & os, intrusive_ptr<Y, VP> const & p)
{ os << p.get(); return os; }
//!Returns p.get().
//!Does not throw
template<class T, class VP>
inline typename boost::interprocess::intrusive_ptr<T, VP>::pointer
to_raw_pointer(intrusive_ptr<T, VP> p)
{ return p.get(); }
/*Emulates static cast operator. Does not throw*/
/*
template<class T, class U, class VP>
inline boost::interprocess::intrusive_ptr<T, VP> static_pointer_cast
(boost::interprocess::intrusive_ptr<U, VP> const & p)
{ return do_static_cast<U>(p.get()); }
*/
/*Emulates const cast operator. Does not throw*/
/*
template<class T, class U, class VP>
inline boost::interprocess::intrusive_ptr<T, VP> const_pointer_cast
(boost::interprocess::intrusive_ptr<U, VP> const & p)
{ return do_const_cast<U>(p.get()); }
*/
/*Emulates dynamic cast operator. Does not throw*/
/*
template<class T, class U, class VP>
inline boost::interprocess::intrusive_ptr<T, VP> dynamic_pointer_cast
(boost::interprocess::intrusive_ptr<U, VP> const & p)
{ return do_dynamic_cast<U>(p.get()); }
*/
/*Emulates reinterpret cast operator. Does not throw*/
/*
template<class T, class U, class VP>
inline boost::interprocess::intrusive_ptr<T, VP>reinterpret_pointer_cast
(boost::interprocess::intrusive_ptr<U, VP> const & p)
{ return do_reinterpret_cast<U>(p.get()); }
*/
} // namespace interprocess
/// @cond
#if defined(_MSC_VER) && (_MSC_VER < 1400)
//!Returns p.get().
//!Does not throw
template<class T, class VP>
inline T *to_raw_pointer(boost::interprocess::intrusive_ptr<T, VP> p)
{ return p.get(); }
#endif
/// @endcond
} // namespace boost
#include <boost/interprocess/detail/config_end.hpp>
#endif // #ifndef BOOST_INTERPROCESS_INTRUSIVE_PTR_HPP_INCLUDED