src/dawn/common/WeakRefSupport.cpp

// Copyright 2023 The Dawn & Tint Authors
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#include "dawn/common/WeakRefSupport.h"

#include <utility>

namespace dawn::detail {

WeakRefData::WeakRefData(RefCounted* value) : mValue(value) {}

Ref<RefCounted> WeakRefData::TryGetRef() {
    std::lock_guard<std::mutex> lock(mMutex);
    if (!mValue || !mValue->mRefCount.TryIncrement()) {
        return nullptr;
    }
    return AcquireRef(mValue);
}

RefCounted* WeakRefData::UnsafeGet() const {
    return mValue;
}

void WeakRefData::Invalidate() {
    std::lock_guard<std::mutex> lock(mMutex);
    mValue = nullptr;
}

WeakRefSupportBase::WeakRefSupportBase(Ref<detail::WeakRefData> data) : mData(std::move(data)) {}

WeakRefSupportBase::~WeakRefSupportBase() {
    mData->Invalidate();
}

}  // namespace dawn::detail