|  | // Copyright 2020 The Dawn 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 | 
|  | // | 
|  | //     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 COMMON_IOKITREF_H_ | 
|  | #define COMMON_IOKITREF_H_ | 
|  |  | 
|  | #include "common/RefBase.h" | 
|  |  | 
|  | #include <IOKit/IOKitLib.h> | 
|  |  | 
|  | template <typename T> | 
|  | struct IOKitRefTraits { | 
|  | static constexpr T kNullValue = IO_OBJECT_NULL; | 
|  | static void Reference(T value) { | 
|  | IOObjectRetain(value); | 
|  | } | 
|  | static void Release(T value) { | 
|  | IOObjectRelease(value); | 
|  | } | 
|  | }; | 
|  |  | 
|  | template <typename T> | 
|  | class IORef : public RefBase<T, IOKitRefTraits<T>> { | 
|  | public: | 
|  | using RefBase<T, IOKitRefTraits<T>>::RefBase; | 
|  | }; | 
|  |  | 
|  | template <typename T> | 
|  | IORef<T> AcquireIORef(T pointee) { | 
|  | IORef<T> ref; | 
|  | ref.Acquire(pointee); | 
|  | return ref; | 
|  | } | 
|  |  | 
|  | #endif  // COMMON_IOKITREF_H_ |