* 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_INCLUDE_FUTURE_H
#define OHOS_WM_INCLUDE_FUTURE_H
#include <condition_variable>
#include "hilog/log.h"
#include "window_manager_hilog.h"
#include "dms_global_mutex.h"
namespace OHOS::Rosen {
template<class T>
class Future {
public:
T GetResult(long timeOut)
{
std::unique_lock <std::mutex> lock(mutex_);
if (!DmUtils::safe_wait_for(conditionVariable_, lock,
std::chrono::milliseconds(timeOut), [this] { return IsReady(); })) {
TLOGE(WmsLogTag::DEFAULT, "wait for %{public}ld, timeout.", timeOut);
}
return FetchResult();
}
protected:
virtual bool IsReady() = 0;
virtual T FetchResult() = 0;
virtual void Call(T) = 0;
void FutureCall(T t)
{
std::unique_lock <std::mutex> lock(mutex_);
Call(t);
conditionVariable_.notify_one();
}
std::mutex mutex_;
protected:
std::condition_variable conditionVariable_;
};
template<class T>
class RunnableFuture : public Future<T> {
public:
void SetValue(T res)
{
Future<T>::FutureCall(res);
}
void Reset(T defaultValue)
{
flag_ = false;
result_ = defaultValue;
}
void ResetLock(T defaultValue)
{
std::unique_lock <std::mutex> lock(Future<T>::mutex_);
flag_ = false;
result_ = defaultValue;
}
protected:
void Call(T res) override
{
if (!flag_) {
flag_ = true;
result_ = res;
}
}
bool IsReady() override
{
return flag_;
}
T FetchResult() override
{
return result_;
}
private:
bool flag_ {false};
T result_;
};
}
#endif
