blob: e6532da165541fb06c21cee39032572cf7b8627e [file] [log] [blame]
// Copyright (c) 2011 The Chromium 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 "remoting/base/rate_counter.h"
#include "base/logging.h"
namespace remoting {
RateCounter::RateCounter(base::TimeDelta time_window)
: time_window_(time_window),
sum_(0) {
DCHECK_GT(time_window.InMilliseconds(), 0);
}
RateCounter::~RateCounter() {
}
void RateCounter::Record(int64 value) {
DCHECK(CalledOnValidThread());
base::Time current_time = CurrentTime();
EvictOldDataPoints(current_time);
sum_ += value;
data_points_.push(std::make_pair(current_time, value));
}
double RateCounter::Rate() {
DCHECK(CalledOnValidThread());
EvictOldDataPoints(CurrentTime());
return sum_ / time_window_.InSecondsF();
}
void RateCounter::SetCurrentTimeForTest(base::Time current_time) {
DCHECK(CalledOnValidThread());
DCHECK(current_time >= current_time_for_test_);
current_time_for_test_ = current_time;
}
void RateCounter::EvictOldDataPoints(base::Time current_time) {
// Remove data points outside of the window.
base::Time window_start = current_time - time_window_;
while (!data_points_.empty()) {
if (data_points_.front().first > window_start)
break;
sum_ -= data_points_.front().second;
data_points_.pop();
}
}
base::Time RateCounter::CurrentTime() const {
if (current_time_for_test_ == base::Time())
return base::Time::Now();
return current_time_for_test_;
}
} // namespace remoting