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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "RTCStatsReport.h"
#include "libwebrtcglue/SystemTime.h"
#include "mozilla/dom/Performance.h"
#include "nsRFPService.h"
#include "WebrtcGlobal.h"
namespace mozilla::dom {
RTCStatsTimestampState::RTCStatsTimestampState()
: mRandomTimelineSeed(0),
mStartDomRealtime(WebrtcSystemTimeBase()),
mStartRealtime(
WebrtcSystemTime() -
webrtc::TimeDelta::Micros(
(TimeStamp::Now() - mStartDomRealtime).ToMicroseconds())),
mRTPCallerType(RTPCallerType::Normal),
mStartWallClockRaw(
PerformanceService::GetOrCreate()->TimeOrigin(mStartDomRealtime)) {}
RTCStatsTimestampState::RTCStatsTimestampState(Performance& aPerformance)
: mRandomTimelineSeed(aPerformance.GetRandomTimelineSeed()),
mStartDomRealtime(aPerformance.CreationTimeStamp()),
mStartRealtime(
WebrtcSystemTime() -
webrtc::TimeDelta::Micros(
(TimeStamp::Now() - mStartDomRealtime).ToMicroseconds())),
mRTPCallerType(aPerformance.GetRTPCallerType()),
mStartWallClockRaw(
PerformanceService::GetOrCreate()->TimeOrigin(mStartDomRealtime)) {}
TimeStamp RTCStatsTimestamp::ToMozTime() const { return mMozTime; }
webrtc::Timestamp RTCStatsTimestamp::ToRealtime() const {
return ToDomRealtime() +
webrtc::TimeDelta::Micros(mState.mStartRealtime.us());
}
webrtc::Timestamp RTCStatsTimestamp::To1Jan1970() const {
return ToDomRealtime() + webrtc::TimeDelta::Millis(mState.mStartWallClockRaw);
}
webrtc::Timestamp RTCStatsTimestamp::ToNtp() const {
return To1Jan1970() + webrtc::TimeDelta::Seconds(webrtc::kNtpJan1970);
}
webrtc::Timestamp RTCStatsTimestamp::ToDomRealtime() const {
return webrtc::Timestamp::Micros(
(mMozTime - mState.mStartDomRealtime).ToMicroseconds());
}
DOMHighResTimeStamp RTCStatsTimestamp::ToDom() const {
// webrtc-pc says to use performance.timeOrigin + performance.now(), but
// keeping a Performance object around is difficult because it is
// main-thread-only. So, we perform the same calculation here. Note that this
// can be very different from the current wall-clock time because of changes
// to the wall clock, or monotonic clock drift over long periods of time.
// We are very careful to do exactly what Performance does, to avoid timestamp
// discrepancies.
DOMHighResTimeStamp realtime = ToDomRealtime().ms<double>();
// mRandomTimelineSeed is not set in the unit-tests.
if (mState.mRandomTimelineSeed) {
realtime = nsRFPService::ReduceTimePrecisionAsMSecs(
realtime, mState.mRandomTimelineSeed, mState.mRTPCallerType);
}
// Ugh. Performance::TimeOrigin is not constant, which means we need to
// emulate this weird behavior so our time stamps are consistent with JS
// timeOrigin. This is based on the code here:
// 053826b10f838f77c27507e5efecc96e34718541/dom/performance/Performance.cpp#111-117
DOMHighResTimeStamp start = nsRFPService::ReduceTimePrecisionAsMSecs(
mState.mStartWallClockRaw, 0, mState.mRTPCallerType);
return start + realtime;
}
/* static */ RTCStatsTimestamp RTCStatsTimestamp::FromMozTime(
const RTCStatsTimestampMaker& aMaker, TimeStamp aMozTime) {
return RTCStatsTimestamp(aMaker.mState, aMozTime);
}
/* static */ RTCStatsTimestamp RTCStatsTimestamp::FromRealtime(
const RTCStatsTimestampMaker& aMaker, webrtc::Timestamp aRealtime) {
return FromDomRealtime(
aMaker,
aRealtime - webrtc::TimeDelta::Micros(aMaker.mState.mStartRealtime.us()));
}
/* static */ RTCStatsTimestamp RTCStatsTimestamp::From1Jan1970(
const RTCStatsTimestampMaker& aMaker, webrtc::Timestamp a1Jan1970) {
const auto& state = aMaker.mState;
return FromDomRealtime(
aMaker, a1Jan1970 - webrtc::TimeDelta::Millis(state.mStartWallClockRaw));
}
/* static */ RTCStatsTimestamp RTCStatsTimestamp::FromNtp(
const RTCStatsTimestampMaker& aMaker, webrtc::Timestamp aNtpTime) {
const auto& state = aMaker.mState;
const auto domRealtime = aNtpTime -
webrtc::TimeDelta::Seconds(webrtc::kNtpJan1970) -
webrtc::TimeDelta::Millis(state.mStartWallClockRaw);
// Ntp times exposed by libwebrtc to stats are always **rounded** to
// milliseconds. That means they can jump up to half a millisecond into the
// future. We compensate for that here so that things seem consistent to js.
return FromDomRealtime(aMaker, domRealtime - webrtc::TimeDelta::Micros(500));
}
/* static */ RTCStatsTimestamp RTCStatsTimestamp::FromDomRealtime(
const RTCStatsTimestampMaker& aMaker, webrtc::Timestamp aDomRealtime) {
return RTCStatsTimestamp(aMaker.mState, aMaker.mState.mStartDomRealtime +
TimeDuration::FromMicroseconds(
aDomRealtime.us<double>()));
}
RTCStatsTimestamp::RTCStatsTimestamp(RTCStatsTimestampState aState,
TimeStamp aMozTime)
: mState(aState), mMozTime(aMozTime) {}
RTCStatsTimestampMaker::RTCStatsTimestampMaker(RTCStatsTimestampState aState)
: mState(aState) {}
/* static */
RTCStatsTimestampMaker RTCStatsTimestampMaker::Create(
nsPIDOMWindowInner* aWindow /* = nullptr */) {
if (!aWindow) {
return RTCStatsTimestampMaker(RTCStatsTimestampState());
}
if (Performance* p = aWindow->GetPerformance()) {
return RTCStatsTimestampMaker(RTCStatsTimestampState(*p));
}
return RTCStatsTimestampMaker(RTCStatsTimestampState());
}
RTCStatsTimestamp RTCStatsTimestampMaker::GetNow() const {
return RTCStatsTimestamp::FromMozTime(*this, TimeStamp::Now());
}
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(RTCStatsReport, mParent)
RTCStatsReport::RTCStatsReport(nsPIDOMWindowInner* aParent)
: mParent(aParent) {}
/*static*/
already_AddRefed<RTCStatsReport> RTCStatsReport::Constructor(
const GlobalObject& aGlobal) {
nsCOMPtr<nsPIDOMWindowInner> window(
do_QueryInterface(aGlobal.GetAsSupports()));
RefPtr<RTCStatsReport> report(new RTCStatsReport(window));
return report.forget();
}
JSObject* RTCStatsReport::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return RTCStatsReport_Binding::Wrap(aCx, this, aGivenProto);
}
void RTCStatsReport::Incorporate(RTCStatsCollection& aStats) {
ForAllPublicRTCStatsCollectionMembers(
aStats, [&](auto... aMember) { (SetRTCStats(aMember), ...); });
}
void RTCStatsReport::Set(const nsAString& aKey, JS::Handle<JSObject*> aValue,
ErrorResult& aRv) {
RTCStatsReport_Binding::MaplikeHelpers::Set(this, aKey, aValue, aRv);
}
namespace {
template <size_t I, typename... Ts>
bool MoveInto(std::tuple<Ts...>& aFrom, std::tuple<Ts*...>& aInto) {
return std::get<I>(aInto)->AppendElements(std::move(std::get<I>(aFrom)),
fallible);
}
template <size_t... Is, typename... Ts>
bool MoveInto(std::tuple<Ts...>&& aFrom, std::tuple<Ts*...>& aInto,
std::index_sequence<Is...>) {
return (... && MoveInto<Is>(aFrom, aInto));
}
template <typename... Ts>
bool MoveInto(std::tuple<Ts...>&& aFrom, std::tuple<Ts*...>& aInto) {
return MoveInto(std::move(aFrom), aInto, std::index_sequence_for<Ts...>());
}
} // namespace
void MergeStats(UniquePtr<RTCStatsCollection> aFromStats,
RTCStatsCollection* aIntoStats) {
auto fromTuple = ForAllRTCStatsCollectionMembers(
*aFromStats,
[&](auto&... aMember) { return std::make_tuple(std::move(aMember)...); });
auto intoTuple = ForAllRTCStatsCollectionMembers(
*aIntoStats,
[&](auto&... aMember) { return std::make_tuple(&aMember...); });
if (!MoveInto(std::move(fromTuple), intoTuple)) {
mozalloc_handle_oom(0);
}
}
void FlattenStats(nsTArray<UniquePtr<RTCStatsCollection>> aFromStats,
RTCStatsCollection* aIntoStats) {
for (auto& stats : aFromStats) {
MergeStats(std::move(stats), aIntoStats);
}
}
} // namespace mozilla::dom