| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef NVRAM_MESSAGES_TYPE_TRAITS_H_ |
| #define NVRAM_MESSAGES_TYPE_TRAITS_H_ |
| |
| extern "C" { |
| #include <stddef.h> |
| } |
| |
| // A subset of utilities similar to what is available in <type_traits>. We have |
| // our own standalone version here since not all target platforms have a full |
| // C++ standard library. |
| |
| namespace nvram { |
| |
| template <typename T> |
| struct remove_const { |
| using Type = T; |
| }; |
| template <typename T> |
| struct remove_const<const T> { |
| using Type = T; |
| }; |
| |
| template <typename T> |
| struct remove_reference { |
| using Type = T; |
| }; |
| template <typename T> |
| struct remove_reference<T&> { |
| using Type = T; |
| }; |
| template <typename T> |
| struct remove_reference<T&&> { |
| using Type = T; |
| }; |
| |
| template <bool value, typename T = void> |
| struct enable_if {}; |
| |
| template <typename T> |
| struct enable_if<true, T> { |
| using Type = T; |
| }; |
| |
| template <typename T, T const_value> |
| struct integral_constant { |
| static constexpr T value = const_value; |
| }; |
| |
| using true_type = integral_constant<bool, true>; |
| using false_type = integral_constant<bool, false>; |
| |
| template <typename T> |
| T declval(); |
| |
| template <size_t... index> |
| struct index_sequence {}; |
| |
| template <size_t size, size_t... indices> |
| struct make_index_sequence_builder { |
| using Type = typename make_index_sequence_builder<size - 1, |
| size - 1, |
| indices...>::Type; |
| }; |
| |
| template <size_t... indices> |
| struct make_index_sequence_builder<0, indices...> { |
| using Type = index_sequence<indices...>; |
| }; |
| |
| template <size_t size> |
| constexpr typename make_index_sequence_builder<size>::Type |
| make_index_sequence(){ |
| return typename make_index_sequence_builder<size>::Type(); |
| }; |
| |
| } // namespace nvram |
| |
| #endif // NVRAM_MESSAGES_TYPE_TRAITS_H_ |