// Copyright 2025 The Dawn & Tint Authors
//
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// modification, are permitted provided that the following conditions are met:
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// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
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// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
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//    this software without specific prior written permission.
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#include "dawn/native/DeviceGuard.h"

#include <utility>

#include "dawn/common/Assert.h"
#include "dawn/native/Device.h"

namespace dawn::native {

DeviceMutex::~DeviceMutex() {
    DAWN_ASSERT(mRecursionStackDepth == 0);
}

void DeviceMutex::Lock() {
    RecursiveMutex::Lock();
    if (mRecursionStackDepth == 0) {
        mDefer.emplace();
    }
    mRecursionStackDepth++;
}

void DeviceMutex::Unlock() {
    // Optional Defer here is used to destroy the Defer object after releasing the lock.
    std::optional<class Defer> defer;

    mRecursionStackDepth--;
    if (mRecursionStackDepth == 0) {
        defer.swap(mDefer);
    }
    RecursiveMutex::Unlock();
}

namespace detail {

DeviceGuardBase::DeviceGuardBase(DeviceMutex* mutex) : mMutex(mutex) {}

}  // namespace detail

DeviceGuard::DeviceGuard(DeviceBase* device, DeviceMutex* mutex)
    : detail::DeviceGuardBase(mutex), GuardBase(device, device->mMutex) {}

DeviceGuard::DeviceGuard(DeviceGuard&& other)
    : detail::DeviceGuardBase(std::move(other)), GuardBase(std::move(other)) {}

}  // namespace dawn::native