Chris@16: // Copyright David Abrahams 2002.
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: #ifndef REFERENT_STORAGE_DWA200278_HPP
Chris@16: # define REFERENT_STORAGE_DWA200278_HPP
Chris@16: # include <boost/mpl/if.hpp>
Chris@16: # include <cstddef>
Chris@16: 
Chris@16: namespace boost { namespace python { namespace detail {
Chris@16: 
Chris@16: struct alignment_dummy;
Chris@16: typedef void (*function_ptr)();
Chris@16: typedef int (alignment_dummy::*member_ptr);
Chris@16: typedef int (alignment_dummy::*member_function_ptr)();
Chris@16: 
Chris@16: # define BOOST_PYTHON_ALIGNER(T, n)                     \
Chris@16:         typename mpl::if_c<                             \
Chris@16:            sizeof(T) <= size, T, char>::type t##n
Chris@16: 
Chris@16: // Storage for size bytes, aligned to all fundamental types no larger than size
Chris@16: template <std::size_t size>
Chris@16: union aligned_storage
Chris@16: {
Chris@16:     BOOST_PYTHON_ALIGNER(char, 0);
Chris@16:     BOOST_PYTHON_ALIGNER(short, 1);
Chris@16:     BOOST_PYTHON_ALIGNER(int, 2);
Chris@16:     BOOST_PYTHON_ALIGNER(long, 3);
Chris@16:     BOOST_PYTHON_ALIGNER(float, 4);
Chris@16:     BOOST_PYTHON_ALIGNER(double, 5);
Chris@16:     BOOST_PYTHON_ALIGNER(long double, 6);
Chris@16:     BOOST_PYTHON_ALIGNER(void*, 7);
Chris@16:     BOOST_PYTHON_ALIGNER(function_ptr, 8);
Chris@16:     BOOST_PYTHON_ALIGNER(member_ptr, 9);
Chris@16:     BOOST_PYTHON_ALIGNER(member_function_ptr, 10);
Chris@16:     char bytes[size];
Chris@16: };
Chris@16: 
Chris@16: # undef BOOST_PYTHON_ALIGNER
Chris@16: 
Chris@16:   // Compute the size of T's referent. We wouldn't need this at all,
Chris@16:   // but sizeof() is broken in CodeWarriors <= 8.0
Chris@16:   template <class T> struct referent_size;
Chris@16:   
Chris@16: # ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
Chris@16:   
Chris@16:   template <class T>
Chris@16:   struct referent_size<T&>
Chris@16:   {
Chris@16:       BOOST_STATIC_CONSTANT(
Chris@16:           std::size_t, value = sizeof(T));
Chris@16:   };
Chris@16: 
Chris@16: # else
Chris@16: 
Chris@16:   template <class T> struct referent_size
Chris@16:   {
Chris@16:       static T f();
Chris@16:       BOOST_STATIC_CONSTANT(std::size_t, value = sizeof(f()));
Chris@16:   };
Chris@16:   
Chris@16: # endif
Chris@16: 
Chris@16: // A metafunction returning a POD type which can store U, where T ==
Chris@16: // U&. If T is not a reference type, returns a POD which can store T.
Chris@16: template <class T>
Chris@16: struct referent_storage
Chris@16: {
Chris@16:     typedef aligned_storage<
Chris@16:         ::boost::python::detail::referent_size<T>::value
Chris@16:     > type;
Chris@16: };
Chris@16: 
Chris@16: }}} // namespace boost::python::detail
Chris@16: 
Chris@16: #endif // REFERENT_STORAGE_DWA200278_HPP