ceph/src/boost/boost/type_erasure/detail/adapt_to_vtable.hpp

   1 // Boost.TypeErasure library
   2 //
   3 // Copyright 2011 Steven Watanabe
   4 //
   5 // Distributed under the Boost Software License Version 1.0. (See
   6 // accompanying file LICENSE_1_0.txt or copy at
   7 // http://www.boost.org/LICENSE_1_0.txt)
   8 //
   9 // $Id$
  10
  11 #if !defined(BOOST_PP_IS_ITERATING)
  12
  13 #ifndef BOOST_TYPE_ERASURE_DETAIL_ADAPT_TO_VTABLE_HPP_INCLUDED
  14 #define BOOST_TYPE_ERASURE_DETAIL_ADAPT_TO_VTABLE_HPP_INCLUDED
  15
  16 #include <boost/detail/workaround.hpp>
  17 #include <boost/utility/addressof.hpp>
  18 #include <boost/mpl/if.hpp>
  19 #include <boost/mpl/eval_if.hpp>
  20 #include <boost/mpl/has_xxx.hpp>
  21 #include <boost/type_traits/function_traits.hpp>
  22 #include <boost/type_traits/remove_cv.hpp>
  23 #include <boost/preprocessor/cat.hpp>
  24 #include <boost/preprocessor/iteration/iterate.hpp>
  25 #include <boost/preprocessor/repetition/enum.hpp>
  26 #include <boost/preprocessor/repetition/enum_params.hpp>
  27 #include <boost/preprocessor/repetition/enum_trailing_params.hpp>
  28 #include <boost/preprocessor/repetition/enum_binary_params.hpp>
  29 #include <boost/type_erasure/detail/get_signature.hpp>
  30 #include <boost/type_erasure/detail/storage.hpp>
  31 #include <boost/type_erasure/is_placeholder.hpp>
  32 #include <boost/type_erasure/config.hpp>
  33
  34 namespace boost {
  35 namespace type_erasure {
  36
  37 namespace detail {
  38
  39 template<class T, class Out>
  40 struct get_placeholders;
  41
  42 template<class PrimitiveConcept, class Sig>
  43 struct vtable_adapter;
  44
  45 template<class PrimitiveConcept, class Sig, class Out>
  46 struct get_placeholders<vtable_adapter<PrimitiveConcept, Sig>, Out>
  47 {
  48     typedef typename get_placeholders<PrimitiveConcept, Out>::type type;
  49 };
  50
  51 template<class T>
  52 struct replace_param_for_vtable
  53 {
  54     typedef typename ::boost::mpl::if_<
  55         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
  56         const ::boost::type_erasure::detail::storage&,
  57         T
  58     >::type type;
  59 };
  60
  61 template<class T>
  62 struct replace_param_for_vtable<T&>
  63 {
  64     typedef typename ::boost::mpl::if_<
  65         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
  66         ::boost::type_erasure::detail::storage&,
  67         T&
  68     >::type type;
  69 };
  70
  71 template<class T>
  72 struct replace_param_for_vtable<const T&>
  73 {
  74     typedef typename ::boost::mpl::if_<
  75         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
  76         const ::boost::type_erasure::detail::storage&,
  77         const T&
  78     >::type type;
  79 };
  80
  81 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
  82
  83 template<class T>
  84 struct replace_param_for_vtable<T&&>
  85 {
  86     typedef typename ::boost::mpl::if_<
  87         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
  88         ::boost::type_erasure::detail::storage&&,
  89         T&&
  90     >::type type;
  91 };
  92
  93 #endif
  94
  95 template<class T>
  96 struct replace_result_for_vtable
  97 {
  98     typedef typename ::boost::mpl::if_<
  99         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
 100         ::boost::type_erasure::detail::storage,
 101         T
 102     >::type type;
 103 };
 104
 105 template<class T>
 106 struct replace_result_for_vtable<T&>
 107 {
 108     typedef typename ::boost::mpl::if_<
 109         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
 110         ::boost::type_erasure::detail::storage&,
 111         T&
 112     >::type type;
 113 };
 114
 115 template<class T>
 116 struct replace_result_for_vtable<const T&>
 117 {
 118     typedef typename ::boost::mpl::if_<
 119         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
 120         ::boost::type_erasure::detail::storage&,
 121         const T&
 122     >::type type;
 123 };
 124
 125 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
 126
 127 template<class T>
 128 struct replace_result_for_vtable<T&&>
 129 {
 130     typedef typename ::boost::mpl::if_<
 131         ::boost::type_erasure::is_placeholder<typename ::boost::remove_cv<T>::type>,
 132         ::boost::type_erasure::detail::storage&&,
 133         T&&
 134     >::type type;
 135 };
 136
 137 #endif
 138
 139 template<class Sig>
 140 struct get_vtable_signature;
 141
 142 BOOST_MPL_HAS_XXX_TRAIT_DEF(type)
 143
 144 template<class T>
 145 struct is_internal_concept :
 146     ::boost::type_erasure::detail::has_type<T>
 147 {};
 148
 149 template<class PrimitiveConcept>
 150 struct adapt_to_vtable
 151 {
 152     typedef ::boost::type_erasure::detail::vtable_adapter<
 153         PrimitiveConcept,
 154         typename ::boost::type_erasure::detail::get_vtable_signature<
 155             typename ::boost::type_erasure::detail::get_signature<
 156                 PrimitiveConcept
 157             >::type
 158         >::type
 159     > type;
 160 };
 161
 162 template<class Concept>
 163 struct maybe_adapt_to_vtable
 164 {
 165     typedef typename ::boost::mpl::eval_if<
 166         ::boost::type_erasure::detail::is_internal_concept<Concept>,
 167         ::boost::mpl::identity<Concept>,
 168         ::boost::type_erasure::detail::adapt_to_vtable<Concept>
 169     >::type type;
 170 };
 171
 172 #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && \
 173     !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \
 174     !BOOST_WORKAROUND(BOOST_MSVC, == 1800)
 175
 176 template<class PrimitiveConcept, class Sig, class ConceptSig>
 177 struct vtable_adapter_impl;
 178
 179 template<class PrimitiveConcept, class R, class... T, class R2, class... U>
 180 struct vtable_adapter_impl<PrimitiveConcept, R(T...), R2(U...)>
 181 {
 182     typedef R (*type)(T...);
 183     static R value(T... arg)
 184     {
 185         return PrimitiveConcept::apply(
 186             ::boost::type_erasure::detail::extract<U>(std::forward<T>(arg))...);
 187     }
 188 };
 189
 190 template<class PrimitiveConcept, class... T, class R2, class... U>
 191 struct vtable_adapter_impl<PrimitiveConcept, ::boost::type_erasure::detail::storage(T...), R2(U...)>
 192 {
 193     typedef ::boost::type_erasure::detail::storage (*type)(T...);
 194     static ::boost::type_erasure::detail::storage value(T... arg)
 195     {
 196         return ::boost::type_erasure::detail::storage(
 197             PrimitiveConcept::apply(::boost::type_erasure::detail::extract<U>(std::forward<T>(arg))...));
 198     }
 199 };
 200
 201 template<class PrimitiveConcept, class... T, class R2, class... U>
 202 struct vtable_adapter_impl<PrimitiveConcept, ::boost::type_erasure::detail::storage&(T...), R2(U...)>
 203 {
 204     typedef ::boost::type_erasure::detail::storage (*type)(T...);
 205     static ::boost::type_erasure::detail::storage value(T... arg)
 206     {
 207         ::boost::type_erasure::detail::storage result;
 208         typename ::boost::remove_reference<R2>::type* p =
 209             ::boost::addressof(
 210                 PrimitiveConcept::apply(::boost::type_erasure::detail::extract<U>(std::forward<T>(arg))...));
 211         result.data = const_cast<void*>(static_cast<const void*>(p));
 212         return result;
 213     }
 214 };
 215
 216 template<class PrimitiveConcept, class... T, class R2, class... U>
 217 struct vtable_adapter_impl<PrimitiveConcept, ::boost::type_erasure::detail::storage&&(T...), R2(U...)>
 218 {
 219     typedef ::boost::type_erasure::detail::storage (*type)(T...);
 220     static ::boost::type_erasure::detail::storage value(T... arg)
 221     {
 222         ::boost::type_erasure::detail::storage result;
 223         R2 tmp = PrimitiveConcept::apply(::boost::type_erasure::detail::extract<U>(std::forward<T>(arg))...);
 224         typename ::boost::remove_reference<R2>::type* p = ::boost::addressof(tmp);
 225         result.data = const_cast<void*>(static_cast<const void*>(p));
 226         return result;
 227     }
 228 };
 229
 230 template<class PrimitiveConcept, class Sig>
 231 struct vtable_adapter
 232     : vtable_adapter_impl<
 233         PrimitiveConcept,
 234         Sig,
 235         typename ::boost::type_erasure::detail::get_signature<
 236             PrimitiveConcept
 237         >::type
 238     >
 239 {};
 240
 241 template<class R, class... T>
 242 struct get_vtable_signature<R(T...)>
 243 {
 244     typedef typename ::boost::type_erasure::detail::replace_result_for_vtable<
 245         R
 246     >::type type(typename ::boost::type_erasure::detail::replace_param_for_vtable<T>::type...);
 247 };
 248
 249 #else
 250
 251 #define BOOST_PP_FILENAME_1 <boost/type_erasure/detail/adapt_to_vtable.hpp>
 252 #define BOOST_PP_ITERATION_LIMITS (0, BOOST_TYPE_ERASURE_MAX_ARITY)
 253 #include BOOST_PP_ITERATE()
 254
 255 #endif
 256
 257 }
 258 }
 259 }
 260
 261 #endif
 262
 263 #else
 264
 265 #define N BOOST_PP_ITERATION()
 266
 267 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
 268
 269 #define BOOST_TYPE_ERASURE_EXTRACT(z, n, data)                  \
 270     ::boost::type_erasure::detail::extract<                     \
 271         typename traits::                                       \
 272         BOOST_PP_CAT(BOOST_PP_CAT(arg, BOOST_PP_INC(n)), _type) \
 273     >(std::forward<BOOST_PP_CAT(T, n)>(BOOST_PP_CAT(arg, n)))
 274
 275 #else
 276
 277 #define BOOST_TYPE_ERASURE_EXTRACT(z, n, data)                  \
 278     ::boost::type_erasure::detail::extract<                     \
 279         typename traits::                                       \
 280         BOOST_PP_CAT(BOOST_PP_CAT(arg, BOOST_PP_INC(n)), _type) \
 281     >(BOOST_PP_CAT(arg, n))
 282
 283 #endif
 284
 285 #define BOOST_TYPE_ERASURE_REPLACE_PARAM(z, n, data)                    \
 286     typename ::boost::type_erasure::detail::replace_param_for_vtable<   \
 287         BOOST_PP_CAT(T, n)>::type
 288
 289 template<class PrimitiveConcept, class R
 290     BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
 291 struct vtable_adapter<PrimitiveConcept, R(BOOST_PP_ENUM_PARAMS(N, T))>
 292 {
 293     typedef R (*type)(BOOST_PP_ENUM_PARAMS(N, T));
 294     static R value(BOOST_PP_ENUM_BINARY_PARAMS(N, T, arg))
 295     {
 296 #if N > 0
 297         typedef typename ::boost::function_traits<
 298             typename ::boost::type_erasure::detail::get_signature<
 299                 PrimitiveConcept
 300             >::type
 301         > traits;
 302 #endif
 303         return PrimitiveConcept::apply(
 304             BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_EXTRACT, ~));
 305     }
 306 };
 307
 308 template<class PrimitiveConcept
 309     BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
 310 struct vtable_adapter<PrimitiveConcept, ::boost::type_erasure::detail::storage(BOOST_PP_ENUM_PARAMS(N, T))>
 311 {
 312     typedef ::boost::type_erasure::detail::storage (*type)(BOOST_PP_ENUM_PARAMS(N, T));
 313     static ::boost::type_erasure::detail::storage value(BOOST_PP_ENUM_BINARY_PARAMS(N, T, arg))
 314     {
 315 #if N > 0
 316         typedef typename ::boost::function_traits<
 317             typename ::boost::type_erasure::detail::get_signature<
 318                 PrimitiveConcept
 319             >::type
 320         > traits;
 321 #endif
 322         return ::boost::type_erasure::detail::storage(
 323             PrimitiveConcept::apply(
 324                 BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_EXTRACT, ~)));
 325     }
 326 };
 327
 328 template<class PrimitiveConcept
 329     BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
 330 struct vtable_adapter<PrimitiveConcept, ::boost::type_erasure::detail::storage&(BOOST_PP_ENUM_PARAMS(N, T))>
 331 {
 332     typedef ::boost::type_erasure::detail::storage (*type)(BOOST_PP_ENUM_PARAMS(N, T));
 333     static ::boost::type_erasure::detail::storage value(BOOST_PP_ENUM_BINARY_PARAMS(N, T, arg))
 334     {
 335         typedef typename ::boost::function_traits<
 336             typename ::boost::type_erasure::detail::get_signature<
 337                 PrimitiveConcept
 338             >::type
 339         > traits;
 340         ::boost::type_erasure::detail::storage result;
 341         typename ::boost::remove_reference<typename traits::result_type>::type* p =
 342             ::boost::addressof(
 343                 PrimitiveConcept::apply(BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_EXTRACT, ~)));
 344         result.data = const_cast<void*>(static_cast<const void*>(p));
 345         return result;
 346     }
 347 };
 348
 349 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
 350
 351 template<class PrimitiveConcept
 352     BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
 353 struct vtable_adapter<PrimitiveConcept, ::boost::type_erasure::detail::storage&&(BOOST_PP_ENUM_PARAMS(N, T))>
 354 {
 355     typedef ::boost::type_erasure::detail::storage (*type)(BOOST_PP_ENUM_PARAMS(N, T));
 356     static ::boost::type_erasure::detail::storage value(BOOST_PP_ENUM_BINARY_PARAMS(N, T, arg))
 357     {
 358         typedef typename ::boost::function_traits<
 359             typename ::boost::type_erasure::detail::get_signature<
 360                 PrimitiveConcept
 361             >::type
 362         > traits;
 363         ::boost::type_erasure::detail::storage result;
 364         typename traits::result_type tmp =
 365             PrimitiveConcept::apply(BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_EXTRACT, ~));
 366         typename ::boost::remove_reference<typename traits::result_type>::type* p =
 367             ::boost::addressof(tmp);
 368         result.data = const_cast<void*>(static_cast<const void*>(p));
 369         return result;
 370     }
 371 };
 372
 373 #endif
 374
 375 template<class R BOOST_PP_ENUM_TRAILING_PARAMS(N, class T)>
 376 struct get_vtable_signature<R(BOOST_PP_ENUM_PARAMS(N, T))>
 377 {
 378     typedef typename ::boost::type_erasure::detail::replace_result_for_vtable<
 379         R
 380     >::type type(BOOST_PP_ENUM(N, BOOST_TYPE_ERASURE_REPLACE_PARAM, ~));
 381 };
 382
 383 #undef BOOST_TYPE_ERASURE_REPLACE_PARAM
 384 #undef BOOST_TYPE_ERASURE_EXTRACT
 385 #undef N
 386
 387 #endif