icing/util/timer.h

// Copyright (C) 2019 Google LLC
//
// 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 ICING_UTIL_TIMER_H_
#define ICING_UTIL_TIMER_H_

#include <cstdint>

#include "icing/util/clock.h"

namespace icing {
namespace lib {

// A util class to calculate the elapsed time.
class Timer {
 public:
  // Timer starts.
  Timer() : start_timestamp_milliseconds_(GetSteadyTimeMilliseconds()) {}

  // Returns the elapsed time from when timer started.
  int64_t GetElapsedMilliseconds() {
    return GetSteadyTimeMilliseconds() - start_timestamp_milliseconds_;
  }

 private:
  int64_t start_timestamp_milliseconds_;
};

}  // namespace lib
}  // namespace icing

#endif  // ICING_UTIL_TIMER_H_