src/dawn/common/IOKitRef.h

// Copyright 2020 The Dawn & Tint Authors
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#ifndef SRC_DAWN_COMMON_IOKITREF_H_
#define SRC_DAWN_COMMON_IOKITREF_H_

#include <IOKit/IOKitLib.h>

#include "dawn/common/RefBase.h"

namespace dawn {

template <typename T>
struct IOKitRefTraits {
    static constexpr T kNullValue = IO_OBJECT_NULL;
    static void AddRef(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;
}

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_IOKITREF_H_