boost/python/object/pointer_holder.hpp
#if !defined(BOOST_PP_IS_ITERATING) // Copyright David Abrahams 2001. // 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) # ifndef POINTER_HOLDER_DWA20011215_HPP # define POINTER_HOLDER_DWA20011215_HPP # include <boost/get_pointer.hpp> # include <boost/type.hpp> # include <boost/python/instance_holder.hpp> # include <boost/python/object/inheritance_query.hpp> # include <boost/python/object/forward.hpp> # include <boost/python/pointee.hpp> # include <boost/python/type_id.hpp> # include <boost/python/detail/wrapper_base.hpp> # include <boost/python/detail/force_instantiate.hpp> # include <boost/python/detail/preprocessor.hpp> # include <boost/mpl/if.hpp> # include <boost/mpl/apply.hpp> # include <boost/preprocessor/comma_if.hpp> # include <boost/preprocessor/iterate.hpp> # include <boost/preprocessor/repeat.hpp> # include <boost/preprocessor/debug/line.hpp> # include <boost/preprocessor/enum_params.hpp> # include <boost/preprocessor/repetition/enum_binary_params.hpp> # include <boost/detail/workaround.hpp> # include <boost/type_traits/remove_const.hpp> namespace boost { namespace python { template <class T> class wrapper; }} namespace boost { namespace python { namespace objects { # if BOOST_WORKAROUND(__GNUC__, == 2) # define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) (typename unforward<A##n>::type)objects::do_unforward(a##n,0) # else # define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) objects::do_unforward(a##n,0) # endif template <class Pointer, class Value> struct pointer_holder : instance_holder { typedef Value value_type; pointer_holder(Pointer); // Forward construction to the held object # define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/pointer_holder.hpp>, 1)) # include BOOST_PP_ITERATE() private: // types private: // required holder implementation void* holds(type_info, bool null_ptr_only); template <class T> inline void* holds_wrapped(type_info dst_t, wrapper<T>*,T* p) { return python::type_id<T>() == dst_t ? p : 0; } inline void* holds_wrapped(type_info, ...) { return 0; } private: // data members Pointer m_p; }; template <class Pointer, class Value> struct pointer_holder_back_reference : instance_holder { private: typedef typename python::pointee<Pointer>::type held_type; public: typedef Value value_type; // Not sure about this one -- can it work? The source object // undoubtedly does not carry the correct back reference pointer. pointer_holder_back_reference(Pointer); // Forward construction to the held object # define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/pointer_holder.hpp>, 2)) # include BOOST_PP_ITERATE() private: // required holder implementation void* holds(type_info, bool null_ptr_only); private: // data members Pointer m_p; }; # undef BOOST_PYTHON_UNFORWARD_LOCAL template <class Pointer, class Value> inline pointer_holder<Pointer,Value>::pointer_holder(Pointer p) : m_p(p) { } template <class Pointer, class Value> inline pointer_holder_back_reference<Pointer,Value>::pointer_holder_back_reference(Pointer p) : m_p(p) { } template <class Pointer, class Value> void* pointer_holder<Pointer, Value>::holds(type_info dst_t, bool null_ptr_only) { typedef typename boost::remove_const< Value >::type non_const_value; if (dst_t == python::type_id<Pointer>() && !(null_ptr_only && get_pointer(this->m_p)) ) return &this->m_p; Value* p0 # if BOOST_WORKAROUND(__SUNPRO_CC, BOOST_TESTED_AT(0x590)) = static_cast<Value*>( get_pointer(this->m_p) ) # else = get_pointer(this->m_p) # endif ; non_const_value* p = const_cast<non_const_value*>( p0 ); if (p == 0) return 0; if (void* wrapped = holds_wrapped(dst_t, p, p)) return wrapped; type_info src_t = python::type_id<non_const_value>(); return src_t == dst_t ? p : find_dynamic_type(p, src_t, dst_t); } template <class Pointer, class Value> void* pointer_holder_back_reference<Pointer, Value>::holds(type_info dst_t, bool null_ptr_only) { if (dst_t == python::type_id<Pointer>() && !(null_ptr_only && get_pointer(this->m_p)) ) return &this->m_p; if (!get_pointer(this->m_p)) return 0; Value* p = get_pointer(m_p); if (dst_t == python::type_id<held_type>()) return p; type_info src_t = python::type_id<Value>(); return src_t == dst_t ? p : find_dynamic_type(p, src_t, dst_t); } }}} // namespace boost::python::objects # endif // POINTER_HOLDER_DWA20011215_HPP /* --------------- pointer_holder --------------- */ // For gcc 4.4 compatability, we must include the // BOOST_PP_ITERATION_DEPTH test inside an #else clause. #else // BOOST_PP_IS_ITERATING #if BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 1 # if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100) \ && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201))) # line BOOST_PP_LINE(__LINE__, pointer_holder.hpp) # endif # define N BOOST_PP_ITERATION() # if (N != 0) template< BOOST_PP_ENUM_PARAMS_Z(1, N, class A) > # endif pointer_holder(PyObject* self BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a)) : m_p(new Value( BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil) )) { python::detail::initialize_wrapper(self, get_pointer(this->m_p)); } # undef N /* --------------- pointer_holder_back_reference --------------- */ #elif BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 2 # if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100) \ && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201))) # line BOOST_PP_LINE(__LINE__, pointer_holder.hpp(pointer_holder_back_reference)) # endif # define N BOOST_PP_ITERATION() # if (N != 0) template < BOOST_PP_ENUM_PARAMS_Z(1, N, class A) > # endif pointer_holder_back_reference( PyObject* p BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a)) : m_p(new held_type( p BOOST_PP_COMMA_IF(N) BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil) )) {} # undef N #endif // BOOST_PP_ITERATION_DEPTH() #endif