remoting/base/running_average.cc

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "remoting/base/running_average.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace remoting {
  10
  11 RunningAverage::RunningAverage(int window_size)
  12     : window_size_(window_size),
  13       sum_(0) {
  14   DCHECK_GT(window_size, 0);
  15 }
  16
  17 RunningAverage::~RunningAverage() {
  18 }
  19
  20 void RunningAverage::Record(int64 value) {
  21   base::AutoLock auto_lock(lock_);
  22
  23   data_points_.push_back(value);
  24   sum_ += value;
  25
  26   if (data_points_.size() > window_size_) {
  27     sum_ -= data_points_[0];
  28     data_points_.pop_front();
  29   }
  30 }
  31
  32 double RunningAverage::Average() {
  33   base::AutoLock auto_lock(lock_);
  34
  35   if (data_points_.empty())
  36     return 0;
  37   return static_cast<double>(sum_) / data_points_.size();
  38 }
  39
  40 }  // namespace remoting