1 /*
2  * Copyright (c) 2021 Huawei Device Co., Ltd.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *     http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include "semaphore_utils.h"
17 
18 #include <functional>
19 
20 namespace DistributedDB {
21 using std::unique_lock;
22 using std::lock_guard;
23 using std::mutex;
24 using std::condition_variable;
25 
SemaphoreUtils(int count)26 SemaphoreUtils::SemaphoreUtils(int count)
27     : count_(count)
28 {}
29 
~SemaphoreUtils()30 SemaphoreUtils::~SemaphoreUtils()
31 {}
32 
WaitSemaphore(int waitSecond)33 bool SemaphoreUtils::WaitSemaphore(int waitSecond)
34 {
35     unique_lock<mutex> lock(lockMutex_);
36     bool result = cv_.wait_for(lock, std::chrono::seconds(waitSecond),
37         [this] { return CompareCount(); });
38     if (result == true) {
39         --count_;
40     }
41     return result;
42 }
43 
WaitSemaphore()44 void SemaphoreUtils::WaitSemaphore()
45 {
46     unique_lock<mutex> lock(lockMutex_);
47     cv_.wait(lock, [this] { return CompareCount(); });
48     --count_;
49 }
50 
SendSemaphore()51 void SemaphoreUtils::SendSemaphore()
52 {
53     lock_guard<std::mutex> lock(lockMutex_);
54     count_++;
55     cv_.notify_one();
56 }
57 
CompareCount() const58 bool SemaphoreUtils::CompareCount() const
59 {
60     return count_ > 0;
61 }
62 } // namespace DistributedDB
63