Chris@16: 
Chris@16: //  helper code for dealing with tracking non-boost shared_ptr/weak_ptr
Chris@16: 
Chris@16: // Copyright Frank Mori Hess 2009.
Chris@16: // Distributed under the Boost Software License, Version
Chris@16: // 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: // See http://www.boost.org/libs/signals2 for library home page.
Chris@16: 
Chris@16: #ifndef BOOST_SIGNALS2_FOREIGN_PTR_HPP
Chris@16: #define BOOST_SIGNALS2_FOREIGN_PTR_HPP
Chris@16: 
Chris@16: #include <algorithm>
Chris@16: #include <boost/config.hpp>
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <boost/scoped_ptr.hpp>
Chris@16: #include <boost/smart_ptr/bad_weak_ptr.hpp>
Chris@16: #include <boost/utility/swap.hpp>
Chris@16: 
Chris@16: #ifndef BOOST_NO_CXX11_SMART_PTR
Chris@16: #include <memory>
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost
Chris@16: {
Chris@16:   template<typename T> class shared_ptr;
Chris@16:   template<typename T> class weak_ptr;
Chris@16: 
Chris@16:   namespace signals2
Chris@16:   {
Chris@16:     template<typename WeakPtr> struct weak_ptr_traits
Chris@16:     {};
Chris@16:     template<typename T> struct weak_ptr_traits<boost::weak_ptr<T> >
Chris@16:     {
Chris@16:       typedef boost::shared_ptr<T> shared_type;
Chris@16:     };
Chris@16: #ifndef BOOST_NO_CXX11_SMART_PTR
Chris@16:     template<typename T> struct weak_ptr_traits<std::weak_ptr<T> >
Chris@16:     {
Chris@16:       typedef std::shared_ptr<T> shared_type;
Chris@16:     };
Chris@16: #endif
Chris@16: 
Chris@16:     template<typename SharedPtr> struct shared_ptr_traits
Chris@16:     {};
Chris@16: 
Chris@16:     template<typename T> struct shared_ptr_traits<boost::shared_ptr<T> >
Chris@16:     {
Chris@16:       typedef boost::weak_ptr<T> weak_type;
Chris@16:     };
Chris@16: #ifndef BOOST_NO_CXX11_SMART_PTR
Chris@16:     template<typename T> struct shared_ptr_traits<std::shared_ptr<T> >
Chris@16:     {
Chris@16:       typedef std::weak_ptr<T> weak_type;
Chris@16:     };
Chris@16: #endif
Chris@16: 
Chris@16:     namespace detail
Chris@16:     {
Chris@16:       struct foreign_shared_ptr_impl_base
Chris@16:       {
Chris@16:         virtual ~foreign_shared_ptr_impl_base() {}
Chris@16:         virtual void* get() const = 0;
Chris@16:         virtual foreign_shared_ptr_impl_base * clone() const = 0;
Chris@16:       };
Chris@16: 
Chris@16:       template<typename FSP>
Chris@16:       class foreign_shared_ptr_impl: public foreign_shared_ptr_impl_base
Chris@16:       {
Chris@16:       public:
Chris@16:         foreign_shared_ptr_impl(const FSP &p): _p(p)
Chris@16:         {}
Chris@16:         virtual void * get() const
Chris@16:         {
Chris@16:           return _p.get();
Chris@16:         }
Chris@16:         virtual foreign_shared_ptr_impl * clone() const
Chris@16:         {
Chris@16:           return new foreign_shared_ptr_impl(*this);
Chris@16:         }
Chris@16:       private:
Chris@16:         FSP _p;
Chris@16:       };
Chris@16: 
Chris@16:       class foreign_void_shared_ptr
Chris@16:       {
Chris@16:       public:
Chris@16:         foreign_void_shared_ptr():
Chris@16:           _p(0)
Chris@16:         {}
Chris@16:         foreign_void_shared_ptr(const foreign_void_shared_ptr &other):
Chris@16:           _p(other._p->clone())
Chris@16:         {}
Chris@16:         template<typename FSP>
Chris@16:         explicit foreign_void_shared_ptr(const FSP &fsp):
Chris@16:           _p(new foreign_shared_ptr_impl<FSP>(fsp))
Chris@16:         {}
Chris@16:         ~foreign_void_shared_ptr()
Chris@16:         {
Chris@16:           delete _p;
Chris@16:         }
Chris@16:         foreign_void_shared_ptr & operator=(const foreign_void_shared_ptr &other)
Chris@16:         {
Chris@16:           if(&other == this) return *this;
Chris@16:           foreign_void_shared_ptr(other).swap(*this);
Chris@16:           return *this;
Chris@16:         }
Chris@16:         void swap(foreign_void_shared_ptr &other)
Chris@16:         {
Chris@16:           boost::swap(_p, other._p);
Chris@16:         }
Chris@16:       private:
Chris@16:         foreign_shared_ptr_impl_base *_p;
Chris@16:       };
Chris@16: 
Chris@16:       struct foreign_weak_ptr_impl_base
Chris@16:       {
Chris@16:         virtual ~foreign_weak_ptr_impl_base() {}
Chris@16:         virtual foreign_void_shared_ptr lock() const = 0;
Chris@16:         virtual bool expired() const = 0;
Chris@16:         virtual foreign_weak_ptr_impl_base * clone() const = 0;
Chris@16:       };
Chris@16: 
Chris@16:       template<typename FWP>
Chris@16:       class foreign_weak_ptr_impl: public foreign_weak_ptr_impl_base
Chris@16:       {
Chris@16:       public:
Chris@16:         foreign_weak_ptr_impl(const FWP &p): _p(p)
Chris@16:         {}
Chris@16:         virtual foreign_void_shared_ptr lock() const
Chris@16:         {
Chris@16:           return foreign_void_shared_ptr(_p.lock());
Chris@16:         }
Chris@16:         virtual bool expired() const
Chris@16:         {
Chris@16:           return _p.expired();
Chris@16:         }
Chris@16:         virtual foreign_weak_ptr_impl * clone() const
Chris@16:         {
Chris@16:           return new foreign_weak_ptr_impl(*this);
Chris@16:         }
Chris@16:       private:
Chris@16:         FWP _p;
Chris@16:       };
Chris@16: 
Chris@16:       class foreign_void_weak_ptr
Chris@16:       {
Chris@16:       public:
Chris@16:         foreign_void_weak_ptr()
Chris@16:         {}
Chris@16:         foreign_void_weak_ptr(const foreign_void_weak_ptr &other):
Chris@16:           _p(other._p->clone())
Chris@16:         {}
Chris@16:         template<typename FWP>
Chris@16:         explicit foreign_void_weak_ptr(const FWP &fwp):
Chris@16:           _p(new foreign_weak_ptr_impl<FWP>(fwp))
Chris@16:         {}
Chris@16:         foreign_void_weak_ptr & operator=(const foreign_void_weak_ptr &other)
Chris@16:         {
Chris@16:           if(&other == this) return *this;
Chris@16:           foreign_void_weak_ptr(other).swap(*this);
Chris@16:           return *this;
Chris@16:         }
Chris@16:         void swap(foreign_void_weak_ptr &other)
Chris@16:         {
Chris@16:           boost::swap(_p, other._p);
Chris@16:         }
Chris@16:         foreign_void_shared_ptr lock() const
Chris@16:         {
Chris@16:           return _p->lock();
Chris@16:         }
Chris@16:         bool expired() const
Chris@16:         {
Chris@16:           return _p->expired();
Chris@16:         }
Chris@16:       private:
Chris@16:         boost::scoped_ptr<foreign_weak_ptr_impl_base> _p;
Chris@16:       };
Chris@16:     } // namespace detail
Chris@16: 
Chris@16:   } // namespace signals2
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif  // BOOST_SIGNALS2_FOREIGN_PTR_HPP