chromium/third_party/dawn/src/dawn/common/RefCountedWithExternalCount.h

// Copyright 2022 The Dawn & Tint Authors
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#ifndef SRC_DAWN_COMMON_REFCOUNTEDWITHEXTERNALCOUNT_H_
#define SRC_DAWN_COMMON_REFCOUNTEDWITHEXTERNALCOUNT_H_

#include "dawn/common/RefCounted.h"

namespace dawn {

// RecCountedWithExternalCountBase is a version of RefCounted which tracks a separate
// refcount for calls to APIAddRef/APIRelease (refs added/removed by the application).
// The external refcount starts at 0, and the total refcount starts at 1 - i.e. the first
// ref isn't an external ref.
// When the external refcount drops to zero, WillDropLastExternalRef is called. and it can be called
// more than once.
// The derived class must override the behavior of WillDropLastExternalRef.
template <typename T>
class RefCountedWithExternalCount : public T { … };

}  // namespace dawn

#endif  // SRC_DAWN_COMMON_REFCOUNTEDWITHEXTERNALCOUNT_H_