From: d.frey_at_[hidden]
Date: 2008-04-30 02:28:47
Author: daniel_frey
Date: 2008-04-30 02:28:46 EDT (Wed, 30 Apr 2008)
New Revision: 44914
URL: http://svn.boost.org/trac/boost/changeset/44914
Log:
Reference implementations
Added:
sandbox/libs/smart_ptr/daniel_frey/
sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this.hpp (contents, props changed)
sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this_ctor.hpp (contents, props changed)
Added: sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this.hpp
==============================================================================
--- (empty file)
+++ sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this.hpp 2008-04-30 02:28:46 EDT (Wed, 30 Apr 2008)
@@ -0,0 +1,94 @@
+#ifndef BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
+#define BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
+
+//
+// enable_shared_from_this.hpp
+//
+// Copyright (c) 2002 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/weak_ptr.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/assert.hpp>
+#include <boost/config.hpp>
+
+namespace boost
+{
+
+template< class T > class enable_shared_from_this;
+template< class T, class Y > void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<T> const * pe );
+template< class T, class Y > void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<T> const * pe, void * /*pd*/ );
+
+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;
+ }
+
+// virtual destructor because we need a vtable for dynamic_cast from base to derived to work
+ virtual ~enable_shared_from_this()
+ {
+ }
+
+public:
+
+ shared_ptr<T> shared_from_this()
+ {
+ shared_ptr<T> p( _weak_ptr );
+ BOOST_ASSERT( p.get() == this );
+ return p;
+ }
+
+ shared_ptr<T const> shared_from_this() const
+ {
+ shared_ptr<T const> p( _weak_ptr );
+ BOOST_ASSERT( p.get() == this );
+ return p;
+ }
+
+private:
+
+ mutable weak_ptr<T> _weak_ptr;
+
+ template< class U, class Y > friend void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<U> const * pe );
+ template< class U, class Y > friend void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<U> const * pe, void * /*pd*/ );
+};
+
+template< class T, class Y > inline void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<T> const * pe )
+{
+ if( pe != 0 && pe->_weak_ptr.use_count() == 0 )
+ {
+ T * p = dynamic_cast<T *>( const_cast<enable_shared_from_this<T>*>( pe ) );
+ pe->_weak_ptr = shared_ptr<T>( *ptr, p );
+ }
+}
+
+template< class T, class Y > inline void sp_accept_owner( shared_ptr<Y> const * ptr, enable_shared_from_this<T> const * pe, void * /*pd*/ )
+{
+ if( pe != 0 && pe->_weak_ptr.use_count() == 0 )
+ {
+ T * p = dynamic_cast<T *>( const_cast<enable_shared_from_this<T>*>( pe ) );
+ pe->_weak_ptr = shared_ptr<T>( *ptr, p );
+ }
+}
+
+} // namespace boost
+
+#endif // #ifndef BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
Added: sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this_ctor.hpp
==============================================================================
--- (empty file)
+++ sandbox/libs/smart_ptr/daniel_frey/reference_enable_shared_from_this_ctor.hpp 2008-04-30 02:28:46 EDT (Wed, 30 Apr 2008)
@@ -0,0 +1,127 @@
+#ifndef BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
+#define BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED
+
+//
+// enable_shared_from_this.hpp
+//
+// Copyright (c) 2002 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/weak_ptr.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/assert.hpp>
+#include <boost/config.hpp>
+
+namespace boost
+{
+
+template< class T > class enable_shared_from_this;
+template< class T, class Y > void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<T> const * pe );
+template< class T, class Y > void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<T> const * pe, void * /*pd*/ );
+
+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;
+ }
+
+// virtual destructor because we need a vtable for dynamic_cast from base to derived to work
+ virtual ~enable_shared_from_this()
+ {
+ BOOST_ASSERT( _shared_ptr.use_count() <= 1 ); // make sure no dangling shared_ptr objects exist
+ }
+
+public:
+
+ shared_ptr<T> shared_from_this()
+ {
+ init_weak_once();
+ shared_ptr<T> p( _weak_ptr );
+ BOOST_ASSERT( p.get() == this );
+ return p;
+ }
+
+ shared_ptr<T const> shared_from_this() const
+ {
+ init_weak_once();
+ shared_ptr<T const> p( _weak_ptr );
+ BOOST_ASSERT( p.get() == this );
+ return p;
+ }
+
+private:
+
+ mutable weak_ptr<T> _weak_ptr;
+ mutable shared_ptr<T> _shared_ptr;
+
+ void init_weak_once() const
+ {
+ weak_ptr<T> e;
+ if( !( _weak_ptr < e ) && !( e < _weak_ptr ) )
+ {
+ T * p = dynamic_cast<T *>( const_cast<enable_shared_from_this*>( this ) );
+ _shared_ptr.reset( p, detail::sp_deleter_wrapper() );
+ BOOST_ASSERT( _shared_ptr.get() == this );
+ _weak_ptr = _shared_ptr;
+ }
+ }
+
+ template<typename U>
+ void sp_accept_owner( shared_ptr<U> & owner ) const
+ {
+ if( _weak_ptr.use_count() == 0 )
+ {
+ T * p = dynamic_cast<T *>( const_cast<enable_shared_from_this*>( this ) );
+ _weak_ptr = shared_ptr<T>( owner, p );
+ }else if( _shared_ptr )
+ {
+ BOOST_ASSERT( owner.unique() ); // no weak_ptrs to owner should exist either, but there's no way to check that
+ detail::sp_deleter_wrapper * pd = get_deleter<detail::sp_deleter_wrapper>( _shared_ptr );
+ BOOST_ASSERT( pd != 0 );
+ pd->set_deleter( owner );
+
+ owner.reset( _shared_ptr, owner.get() );
+ _shared_ptr.reset();
+ }
+ }
+
+ template< class U, class Y > friend void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<U> const * pe );
+ template< class U, class Y > friend void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<U> const * pe, void * /*pd*/ );
+};
+
+template< class T, class Y > inline void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<T> const * pe )
+{
+ if( pe != 0 )
+ {
+ pe->sp_accept_owner( *ptr );
+ }
+}
+
+template< class T, class Y > inline void sp_accept_owner( shared_ptr<Y> * ptr, enable_shared_from_this<T> const * pe, void * /*pd*/ )
+{
+ if( pe != 0 )
+ {
+ pe->sp_accept_owner( *ptr );
+ }
+}
+
+} // namespace boost
+
+#endif // #ifndef BOOST_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED