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Editing: deconstruct.hpp
#ifndef BOOST_SIGNALS2_DECONSTRUCT_HPP #define BOOST_SIGNALS2_DECONSTRUCT_HPP // deconstruct.hpp // // A factory function for creating a shared_ptr which creates // an object and its owning shared_ptr with one allocation, similar // to make_shared<T>(). It also supports postconstructors // and predestructors through unqualified calls of adl_postconstruct() and // adl_predestruct, relying on argument-dependent // lookup to find the appropriate postconstructor or predestructor. // Passing arguments to postconstructors is also supported. // // based on make_shared.hpp and make_shared_access patch from Michael Marcin // // Copyright (c) 2007, 2008 Peter Dimov // Copyright (c) 2008 Michael Marcin // Copyright (c) 2009 Frank Mori Hess // // 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 // for more information #include <boost/config.hpp> #include <boost/shared_ptr.hpp> #include <boost/type_traits/alignment_of.hpp> #include <boost/type_traits/remove_const.hpp> #include <boost/type_traits/type_with_alignment.hpp> #include <cstddef> #include <new> namespace boost { template<typename T> class enable_shared_from_this; namespace signals2 { class deconstruct_access; namespace detail { inline void adl_predestruct(...) {} } // namespace detail template<typename T> class postconstructor_invoker { public: operator const shared_ptr<T> & () const { return postconstruct(); } const shared_ptr<T>& postconstruct() const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get())); _postconstructed = true; } return _sp; } #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) template<class... Args> const shared_ptr<T>& postconstruct(Args && ... args) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), std::forward<Args>(args)...); _postconstructed = true; } return _sp; } #else // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) template<typename A1> const shared_ptr<T>& postconstruct(const A1 &a1) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1); _postconstructed = true; } return _sp; } template<typename A1, typename A2> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4, typename A5> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4, const A5 &a5) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4, a5); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4, typename A5, typename A6> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4, const A5 &a5, const A6 &a6) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4, a5, a6); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4, const A5 &a5, const A6 &a6, const A7 &a7) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4, a5, a6, a7); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4, const A5 &a5, const A6 &a6, const A7 &a7, const A8 &a8) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4, a5, a6, a7, a8); _postconstructed = true; } return _sp; } template<typename A1, typename A2, typename A3, typename A4, typename A5, typename A6, typename A7, typename A8, typename A9> const shared_ptr<T>& postconstruct(const A1 &a1, const A2 &a2, const A3 &a3, const A4 &a4, const A5 &a5, const A6 &a6, const A7 &a7, const A8 &a8, const A9 &a9) const { if(!_postconstructed) { adl_postconstruct(_sp, const_cast<typename boost::remove_const<T>::type *>(_sp.get()), a1, a2, a3, a4, a5, a6, a7, a8, a9); _postconstructed = true; } return _sp; } #endif // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) private: friend class boost::signals2::deconstruct_access; postconstructor_invoker(const shared_ptr<T> & sp): _sp(sp), _postconstructed(false) {} shared_ptr<T> _sp; mutable bool _postconstructed; }; namespace detail { template< std::size_t N, std::size_t A > struct sp_aligned_storage { union type { char data_[ N ]; typename boost::type_with_alignment< A >::type align_; }; }; template< class T > class deconstruct_deleter { private: typedef typename sp_aligned_storage< sizeof( T ), ::boost::alignment_of< T >::value >::type storage_type; bool initialized_; storage_type storage_; private: void destroy() { if( initialized_ ) { T* p = reinterpret_cast< T* >( storage_.data_ ); using boost::signals2::detail::adl_predestruct; adl_predestruct(const_cast<typename boost::remove_const<T>::type *>(p)); p->~T(); initialized_ = false; } } public: deconstruct_deleter(): initialized_( false ) { } // this copy constructor is an optimization: we don't need to copy the storage_ member, // and shouldn't be copying anyways after initialized_ becomes true deconstruct_deleter(const deconstruct_deleter &): initialized_( false ) { } ~deconstruct_deleter() { destroy(); } void operator()( T * ) { destroy(); } void * address() { return storage_.data_; } void set_initialized() { initialized_ = true; } }; } // namespace detail class deconstruct_access { public: template< class T > static postconstructor_invoker<T> deconstruct() { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T(); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) // Variadic templates, rvalue reference template< class T, class... Args > static postconstructor_invoker<T> deconstruct( Args && ... args ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( std::forward<Args>( args )... ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } #else template< class T, class A1 > static postconstructor_invoker<T> deconstruct( A1 const & a1 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4, class A5 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4, a5 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4, class A5, class A6 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4, a5, a6 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4, a5, a6, a7 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7, class A8 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7, A8 const & a8 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4, a5, a6, a7, a8 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7, class A8, class A9 > static postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7, A8 const & a8, A9 const & a9 ) { boost::shared_ptr< T > pt( static_cast< T* >( 0 ), detail::deconstruct_deleter< T >() ); detail::deconstruct_deleter< T > * pd = boost::get_deleter< detail::deconstruct_deleter< T > >( pt ); void * pv = pd->address(); new( pv ) T( a1, a2, a3, a4, a5, a6, a7, a8, a9 ); pd->set_initialized(); boost::shared_ptr< T > retval( pt, static_cast< T* >( pv ) ); boost::detail::sp_enable_shared_from_this(&retval, retval.get(), retval.get()); return retval; } #endif }; // Zero-argument versions // // Used even when variadic templates are available because of the new T() vs new T issue template< class T > postconstructor_invoker<T> deconstruct() { return deconstruct_access::deconstruct<T>(); } #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) // Variadic templates, rvalue reference template< class T, class... Args > postconstructor_invoker< T > deconstruct( Args && ... args ) { return deconstruct_access::deconstruct<T>( std::forward<Args>( args )... ); } #else // C++03 version template< class T, class A1 > postconstructor_invoker<T> deconstruct( A1 const & a1 ) { return deconstruct_access::deconstruct<T>(a1); } template< class T, class A1, class A2 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2 ) { return deconstruct_access::deconstruct<T>(a1,a2); } template< class T, class A1, class A2, class A3 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3); } template< class T, class A1, class A2, class A3, class A4 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4); } template< class T, class A1, class A2, class A3, class A4, class A5 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5); } template< class T, class A1, class A2, class A3, class A4, class A5, class A6 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5,a6); } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5,a6,a7); } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7, class A8 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7, A8 const & a8 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5,a6,a7,a8); } template< class T, class A1, class A2, class A3, class A4, class A5, class A6, class A7, class A8, class A9 > postconstructor_invoker<T> deconstruct( A1 const & a1, A2 const & a2, A3 const & a3, A4 const & a4, A5 const & a5, A6 const & a6, A7 const & a7, A8 const & a8, A9 const & a9 ) { return deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5,a6,a7,a8,a9); } #endif } // namespace signals2 } // namespace boost #endif // #ifndef BOOST_SIGNALS2_DECONSTRUCT_HPP
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