1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef NETDUTILS_STOPWATCH_H
18 #define NETDUTILS_STOPWATCH_H
19 
20 #include <chrono>
21 
22 namespace android {
23 namespace netdutils {
24 
25 class Stopwatch {
26   private:
27     using clock = std::chrono::steady_clock;
28     using time_point = std::chrono::time_point<clock>;
29 
30   public:
Stopwatch()31     Stopwatch() : mStart(clock::now()) {}
32     virtual ~Stopwatch() = default;
33 
timeTakenUs()34     int64_t timeTakenUs() const { return getElapsedUs(clock::now()); }
getTimeAndResetUs()35     int64_t getTimeAndResetUs() {
36         const auto& now = clock::now();
37         int64_t elapsed = getElapsedUs(now);
38         mStart = now;
39         return elapsed;
40     }
41 
42   private:
43     time_point mStart;
44 
getElapsedUs(const time_point & now)45     int64_t getElapsedUs(const time_point& now) const {
46         return (std::chrono::duration_cast<std::chrono::microseconds>(now - mStart)).count();
47     }
48 };
49 
50 }  // namespace netdutils
51 }  // namespace android
52 
53 #endif  // NETDUTILS_STOPWATCH_H
54