client/simple_timer_linux.cc

// Copyright 2012 The Goma Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.


#include "simple_timer.h"

#include <cstdint>

#include "glog/logging.h"

namespace devtools_goma {

void SimpleTimer::Start() {
  clock_gettime(CLOCK_MONOTONIC, &start_time_);
}

int64_t SimpleTimer::GetInNanoSeconds() const {
  struct timespec end_time;
  clock_gettime(CLOCK_MONOTONIC, &end_time);

  uint64_t end_time_int =
      end_time.tv_sec * 1000000000LL + end_time.tv_nsec;
  uint64_t start_time_int =
      start_time_.tv_sec * 1000000000LL + start_time_.tv_nsec;

  DCHECK_LE(start_time_int, end_time_int);
  if (end_time_int < start_time_int) {
    // This shouldn't happen, but check.
    LOG(ERROR) << "SimpleTimer is not monotonic:"
               << " start_time=" << start_time_int
               << " end_time=" << end_time_int;
    return 0;
  }

  return static_cast<int64_t>(end_time_int - start_time_int);
}

}  // namespace devtools_goma