blob: e5172f40487c37812f6d5cfe0346e61bcfcd4836 [file] [log] [blame]
* Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
#ifdef UNIT_TEST
#include <ostream> // no-presubmit-check TODO(webrtc:8982)
#endif // UNIT_TEST
#include <cstdlib>
#include <string>
#include <type_traits>
#include "rtc_base/units/unit_base.h"
namespace webrtc {
// TimeDelta represents the difference between two timestamps. Commonly this can
// be a duration. However since two Timestamps are not guaranteed to have the
// same epoch (they might come from different computers, making exact
// synchronisation infeasible), the duration covered by a TimeDelta can be
// undefined. To simplify usage, it can be constructed and converted to
// different units, specifically seconds (s), milliseconds (ms) and
// microseconds (us).
class TimeDelta final : public rtc_units_impl::RelativeUnit<TimeDelta> {
TimeDelta() = delete;
template <int64_t seconds>
static constexpr TimeDelta Seconds() {
return FromStaticFraction<seconds, 1000000>();
template <int64_t ms>
static constexpr TimeDelta Millis() {
return FromStaticFraction<ms, 1000>();
template <int64_t us>
static constexpr TimeDelta Micros() {
return FromStaticValue<us>();
template <typename T>
static TimeDelta seconds(T seconds) {
static_assert(std::is_arithmetic<T>::value, "");
return FromFraction<1000000>(seconds);
template <typename T>
static TimeDelta ms(T milliseconds) {
static_assert(std::is_arithmetic<T>::value, "");
return FromFraction<1000>(milliseconds);
template <typename T>
static TimeDelta us(T microseconds) {
static_assert(std::is_arithmetic<T>::value, "");
return FromValue(microseconds);
template <typename T = int64_t>
T seconds() const {
return ToFraction<1000000, T>();
template <typename T = int64_t>
T ms() const {
return ToFraction<1000, T>();
template <typename T = int64_t>
T us() const {
return ToValue<T>();
template <typename T = int64_t>
T ns() const {
return ToMultiple<1000, T>();
constexpr int64_t seconds_or(int64_t fallback_value) const {
return ToFractionOr<1000000>(fallback_value);
constexpr int64_t ms_or(int64_t fallback_value) const {
return ToFractionOr<1000>(fallback_value);
constexpr int64_t us_or(int64_t fallback_value) const {
return ToValueOr(fallback_value);
TimeDelta Abs() const { return TimeDelta::us(std::abs(us())); }
friend class rtc_units_impl::UnitBase<TimeDelta>;
using RelativeUnit::RelativeUnit;
static constexpr bool one_sided = false;
std::string ToString(TimeDelta value);
#ifdef UNIT_TEST
inline std::ostream& operator<<( // no-presubmit-check TODO(webrtc:8982)
std::ostream& stream, // no-presubmit-check TODO(webrtc:8982)
TimeDelta value) {
return stream << ToString(value);
#endif // UNIT_TEST
} // namespace webrtc