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/*
* 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.
*/
#ifndef API_UNITS_TIMESTAMP_H_
#define API_UNITS_TIMESTAMP_H_
#include <cstdint>
#include <string>
#include <type_traits>
#include "api/units/time_delta.h"
#include "rtc_base/checks.h"
#include "rtc_base/units/unit_base.h" // IWYU pragma: export
namespace webrtc {
// Timestamp represents the time that has passed since some unspecified epoch.
// The epoch is assumed to be before any represented timestamps, this means that
// negative values are not valid. The most notable feature is that the
// difference of two Timestamps results in a TimeDelta.
class Timestamp final : public rtc_units_impl::UnitBase<Timestamp> {
public:
template <typename T>
static constexpr Timestamp Seconds(T value) {
static_assert(std::is_arithmetic<T>::value, "");
return FromFraction(1'000'000, value);
}
template <typename T>
static constexpr Timestamp Millis(T value) {
static_assert(std::is_arithmetic<T>::value, "");
return FromFraction(1'000, value);
}
template <typename T>
static constexpr Timestamp Micros(T value) {
static_assert(std::is_arithmetic<T>::value, "");
return FromValue(value);
}
Timestamp() = delete;
template <typename T = int64_t>
constexpr T seconds() const {
return ToFraction<1000000, T>();
}
template <typename T = int64_t>
constexpr T ms() const {
return ToFraction<1000, T>();
}
template <typename T = int64_t>
constexpr T us() const {
return ToValue<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);
}
constexpr Timestamp operator+(const TimeDelta delta) const {
if (IsPlusInfinity() || delta.IsPlusInfinity()) {
RTC_DCHECK(!IsMinusInfinity());
RTC_DCHECK(!delta.IsMinusInfinity());
return PlusInfinity();
} else if (IsMinusInfinity() || delta.IsMinusInfinity()) {
RTC_DCHECK(!IsPlusInfinity());
RTC_DCHECK(!delta.IsPlusInfinity());
return MinusInfinity();
}
return Timestamp::Micros(us() + delta.us());
}
constexpr Timestamp operator-(const TimeDelta delta) const {
if (IsPlusInfinity() || delta.IsMinusInfinity()) {
RTC_DCHECK(!IsMinusInfinity());
RTC_DCHECK(!delta.IsPlusInfinity());
return PlusInfinity();
} else if (IsMinusInfinity() || delta.IsPlusInfinity()) {
RTC_DCHECK(!IsPlusInfinity());
RTC_DCHECK(!delta.IsMinusInfinity());
return MinusInfinity();
}
return Timestamp::Micros(us() - delta.us());
}
constexpr TimeDelta operator-(const Timestamp other) const {
if (IsPlusInfinity() || other.IsMinusInfinity()) {
RTC_DCHECK(!IsMinusInfinity());
RTC_DCHECK(!other.IsPlusInfinity());
return TimeDelta::PlusInfinity();
} else if (IsMinusInfinity() || other.IsPlusInfinity()) {
RTC_DCHECK(!IsPlusInfinity());
RTC_DCHECK(!other.IsMinusInfinity());
return TimeDelta::MinusInfinity();
}
return TimeDelta::Micros(us() - other.us());
}
constexpr Timestamp& operator-=(const TimeDelta delta) {
*this = *this - delta;
return *this;
}
constexpr Timestamp& operator+=(const TimeDelta delta) {
*this = *this + delta;
return *this;
}
private:
friend class rtc_units_impl::UnitBase<Timestamp>;
using UnitBase::UnitBase;
static constexpr bool one_sided = true;
};
std::string ToString(Timestamp value);
inline std::string ToLogString(Timestamp value) {
return ToString(value);
}
} // namespace webrtc
#endif // API_UNITS_TIMESTAMP_H_