python/detail/wrapper_base.hpp

0001 // Copyright David Abrahams 2004. Distributed under the Boost
0002 // Software License, Version 1.0. (See accompanying
0003 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0004 #ifndef WRAPPER_BASE_DWA2004722_HPP
0005 # define WRAPPER_BASE_DWA2004722_HPP
0006
0007 # include <boost/python/detail/prefix.hpp>
0008 # include <boost/python/detail/type_traits.hpp>
0009
0010 namespace boost { namespace python {
0011
0012 class override;
0013
0014 namespace detail
0015 {
0016   class wrapper_base;
0017
0018   namespace wrapper_base_ // ADL disabler
0019   {
0020     inline PyObject* get_owner(wrapper_base const volatile& w);
0021
0022     inline PyObject*
0023     owner_impl(void const volatile* /*x*/, detail::false_)
0024     {
0025         return 0;
0026     }
0027
0028     template <class T>
0029     inline PyObject*
0030     owner_impl(T const volatile* x, detail::true_);
0031
0032     template <class T>
0033     inline PyObject*
0034     owner(T const volatile* x)
0035     {
0036         return wrapper_base_::owner_impl(x,is_polymorphic<T>());
0037     }
0038   }
0039
0040   class BOOST_PYTHON_DECL wrapper_base
0041   {
0042       friend void initialize_wrapper(PyObject* self, wrapper_base* w);
0043       friend PyObject* wrapper_base_::get_owner(wrapper_base const volatile& w);
0044    protected:
0045       wrapper_base() : m_self(0) {}
0046
0047       override get_override(
0048           char const* name, PyTypeObject* class_object) const;
0049
0050    private:
0051       void detach();
0052
0053    private:
0054       PyObject* m_self;
0055   };
0056
0057   namespace wrapper_base_ // ADL disabler
0058   {
0059     template <class T>
0060     inline PyObject*
0061     owner_impl(T const volatile* x, detail::true_)
0062     {
0063         if (wrapper_base const volatile* w = dynamic_cast<wrapper_base const volatile*>(x))
0064         {
0065             return wrapper_base_::get_owner(*w);
0066         }
0067         return 0;
0068     }
0069
0070     inline PyObject* get_owner(wrapper_base const volatile& w)
0071     {
0072         return w.m_self;
0073     }
0074   }
0075
0076   inline void initialize_wrapper(PyObject* self, wrapper_base* w)
0077   {
0078       w->m_self = self;
0079   }
0080
0081   inline void initialize_wrapper(PyObject* /*self*/, ...) {}
0082
0083
0084
0085 } // namespace detail
0086
0087 }} // namespace boost::python
0088
0089 #endif // WRAPPER_BASE_DWA2004722_HPP