| // Copyright 2022 The Pigweed Authors |
| // |
| // 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 |
| // |
| // https://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. |
| #pragma once |
| |
| #include <tuple> |
| |
| namespace pw::sync::internal { |
| |
| // BorrowableStorage stores an object and associated lock. Both objects are |
| // constructed in-place. |
| template <typename ObjectType, typename Lock> |
| class BorrowableStorage { |
| protected: |
| // Construct the object in-place using a list of arguments. |
| template <typename... Args> |
| constexpr explicit BorrowableStorage(std::in_place_t, Args&&... args) |
| : object_{std::forward<Args>(args)...}, lock_ {} |
| {} |
| |
| // Construct the object and lock in-place using the provided parameters. |
| template <typename... ObjectArgs, typename... LockArgs> |
| constexpr BorrowableStorage(std::tuple<ObjectArgs...>&& object_args, |
| std::tuple<LockArgs...>&& lock_args) |
| : object_{std::make_from_tuple<ObjectType>( |
| std::forward<std::tuple<ObjectArgs...>>(object_args))}, |
| lock_{std::make_from_tuple<Lock>( |
| std::forward<std::tuple<LockArgs...>>(lock_args))} {} |
| |
| // Construct the object and lock in-place using the provided factories. |
| template <typename ObjectConstructor, |
| typename LockConstructor, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<ObjectType&&, ObjectConstructor>>, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<Lock&&, LockConstructor>>> |
| constexpr BorrowableStorage(const ObjectConstructor& object_ctor, |
| const LockConstructor& lock_ctor) |
| : object_{object_ctor()}, lock_{lock_ctor()} {} |
| |
| template <typename ObjectConstructor, |
| typename LockConstructor, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<ObjectType&&, ObjectConstructor>>, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<Lock&&, LockConstructor>>> |
| constexpr BorrowableStorage(ObjectConstructor& object_ctor, |
| const LockConstructor& lock_ctor) |
| : object_{object_ctor()}, lock_{lock_ctor()} {} |
| |
| template <typename ObjectConstructor, |
| typename LockConstructor, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<ObjectType&&, ObjectConstructor>>, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<Lock&&, LockConstructor>>> |
| constexpr BorrowableStorage(const ObjectConstructor& object_ctor, |
| LockConstructor& lock_ctor) |
| : object_{object_ctor()}, lock_{lock_ctor()} {} |
| |
| template <typename ObjectConstructor, |
| typename LockConstructor, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<ObjectType&&, ObjectConstructor>>, |
| typename = std::enable_if_t< |
| std::is_invocable_r_v<Lock&&, LockConstructor>>> |
| constexpr BorrowableStorage(ObjectConstructor& object_ctor, |
| LockConstructor& lock_ctor) |
| : object_{object_ctor()}, lock_{lock_ctor()} {} |
| |
| ObjectType object_; |
| Lock lock_; |
| }; |
| |
| template <typename T> |
| T DefaultConstruct() { |
| return T(); |
| } |
| |
| } // namespace pw::sync::internal |
