#ifndef BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED | |
#define BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED | |
// | |
// enable_shared_from_this.hpp | |
// | |
// Copyright 2002, 2009 Peter Dimov | |
// | |
// 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 | |
// | |
// http://www.boost.org/libs/smart_ptr/enable_shared_from_this.html | |
// | |
#include <boost/smart_ptr/weak_ptr.hpp> | |
#include <boost/smart_ptr/shared_ptr.hpp> | |
#include <boost/assert.hpp> | |
#include <boost/config.hpp> | |
namespace boost | |
{ | |
template<class T> class enable_shared_from_this | |
{ | |
protected: | |
enable_shared_from_this() | |
{ | |
} | |
enable_shared_from_this(enable_shared_from_this const &) | |
{ | |
} | |
enable_shared_from_this & operator=(enable_shared_from_this const &) | |
{ | |
return *this; | |
} | |
~enable_shared_from_this() | |
{ | |
} | |
public: | |
shared_ptr<T> shared_from_this() | |
{ | |
shared_ptr<T> p( weak_this_ ); | |
BOOST_ASSERT( p.get() == this ); | |
return p; | |
} | |
shared_ptr<T const> shared_from_this() const | |
{ | |
shared_ptr<T const> p( weak_this_ ); | |
BOOST_ASSERT( p.get() == this ); | |
return p; | |
} | |
public: // actually private, but avoids compiler template friendship issues | |
// Note: invoked automatically by shared_ptr; do not call | |
template<class X, class Y> void _internal_accept_owner( shared_ptr<X> const * ppx, Y * py ) const | |
{ | |
if( weak_this_.expired() ) | |
{ | |
weak_this_ = shared_ptr<T>( *ppx, py ); | |
} | |
} | |
private: | |
mutable weak_ptr<T> weak_this_; | |
}; | |
} // namespace boost | |
#endif // #ifndef BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED |