* Copyright (c) 2021-2022 Huawei Device Co., Ltd.
* 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 OHOS_WM_SINGLE_INSTANCE_H
#define OHOS_WM_SINGLE_INSTANCE_H
#include <mutex>
namespace OHOS {
namespace Rosen {
#define WM_DECLARE_SINGLE_INSTANCE_BASE(className) \
public: \
static className& GetInstance(); \
static bool SetInstance(className* newInstance); \
static void DestroyInstance(); \
className(const className&) = delete; \
className& operator=(const className&) = delete; \
className(className&&) = delete; \
className& operator=(className&&) = delete; \
static className* singleton_; \
static std::mutex singletonMutex_; \
#define WM_DECLARE_SINGLE_INSTANCE(className) \
WM_DECLARE_SINGLE_INSTANCE_BASE(className) \
protected: \
className() = default; \
virtual ~className() = default; \
#define WM_IMPLEMENT_SINGLE_INSTANCE(className) \
className* className::singleton_ = nullptr; \
std::mutex className::singletonMutex_; \
className& className::GetInstance() \
{ \
if (!singleton_) { \
std::lock_guard<std::mutex> lock(singletonMutex_); \
if (!singleton_) { \
singleton_ = new className(); \
} \
} \
return *singleton_; \
} \
bool className::SetInstance(className* newInstance) \
{ \
if (singleton_) { \
return false; \
} \
singleton_ = newInstance; \
return true; \
} \
void className::DestroyInstance() \
{ \
std::lock_guard<std::mutex> lock(singletonMutex_); \
if (!singleton_) { \
delete singleton_; \
singleton_ = nullptr; \
} \
}
}
}
#endif