/* -*- 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
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
#ifndef RTCStatsReport_h_
#define RTCStatsReport_h_
#include "api/units/timestamp.h" // webrtc::Timestamp
#include "js/RootingAPI.h" // JS::Rooted
#include "js/Value.h"
#include "mozilla/dom/AutoEntryScript.h"
#include "mozilla/MozPromise.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/dom/PerformanceService.h"
#include "mozilla/dom/RTCStatsReportBinding.h" // RTCStatsCollection
#include "mozilla/dom/ToJSValue.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/UniquePtr.h"
#include "nsCOMPtr.h"
#include "nsIGlobalObject.h"
#include "nsPIDOMWindow.h" // nsPIDOMWindowInner
#include "nsContentUtils.h"
#include "nsWrapperCache.h"
#include "prtime.h" // PR_Now
namespace mozilla {
extern TimeStamp WebrtcSystemTimeBase();
namespace dom {
/**
* Keeps the state needed to convert RTCStatsTimestamps.
*/
struct RTCStatsTimestampState {
RTCStatsTimestampState();
explicit RTCStatsTimestampState(Performance& aPerformance);
RTCStatsTimestampState(
const RTCStatsTimestampState&) =
default;
// These members are sampled when a non-copy constructor is called.
// Performance's random timeline seed.
const uint64_t mRandomTimelineSeed;
// TimeStamp::Now() when the members were sampled. This is equivalent to time
// 0 in DomRealtime.
const TimeStamp mStartDomRealtime;
// WebrtcSystemTime() when the members were sampled. This represents the same
// point in time as mStartDomRealtime, but as a webrtc timestamp.
const webrtc::Timestamp mStartRealtime;
// Performance's RTPCallerType.
const RTPCallerType mRTPCallerType;
// Performance.timeOrigin for mStartDomRealtime when the members were sampled.
const DOMHighResTimeStamp mStartWallClockRaw;
protected:
RTCStatsTimestampState(TimeStamp aStartDomRealtime,
webrtc::Timestamp aStartRealtime);
};
/**
* Classes that facilitate creating timestamps for webrtc stats by mimicking
* dom::Performance, as well as getting and converting timestamps for libwebrtc
* and our integration with it.
*
* They use the same clock to avoid drift and inconsistencies, base on
* mozilla::TimeStamp, and convert to and from these time bases:
* - Moz : Monotonic, unspecified (but constant) and inaccessible epoch,
* as implemented by mozilla::TimeStamp
* - Realtime : Monotonic, unspecified (but constant) epoch.
* - 1Jan1970 : Monotonic, unix epoch (00:00:00 UTC on 1 January 1970).
* - Ntp : Monotonic, ntp epoch (00:00:00 UTC on 1 January 1900).
* - Dom : Monotonic, milliseconds since unix epoch, as the timestamps
* defined by webrtc-pc. Corresponds to Performance.timeOrigin +
* Performance.now(). Has reduced precision.
* - DomRealtime: Like Dom, but with full precision.
* - WallClock : Non-monotonic, unix epoch. Not used here since it is
* non-monotonic and cannot be correlated to the other time
* bases.
*/
class RTCStatsTimestampMaker;
class RTCStatsTimestamp {
public:
TimeStamp ToMozTime()
const;
webrtc::Timestamp ToRealtime()
const;
webrtc::Timestamp To1Jan1970()
const;
webrtc::Timestamp ToNtp()
const;
webrtc::Timestamp ToDomRealtime()
const;
DOMHighResTimeStamp ToDom()
const;
static RTCStatsTimestamp FromMozTime(
const RTCStatsTimestampMaker& aMaker,
TimeStamp aMozTime);
static RTCStatsTimestamp FromRealtime(
const RTCStatsTimestampMaker& aMaker,
webrtc::Timestamp aRealtime);
static RTCStatsTimestamp From1Jan1970(
const RTCStatsTimestampMaker& aMaker,
webrtc::Timestamp aRealtime);
static RTCStatsTimestamp FromNtp(
const RTCStatsTimestampMaker& aMaker,
webrtc::Timestamp aRealtime);
static RTCStatsTimestamp FromDomRealtime(
const RTCStatsTimestampMaker& aMaker,
webrtc::Timestamp aDomRealtime);
// There is on purpose no conversion functions from DOMHighResTimeStamp
// because of the loss in precision of a floating point to integer conversion.
private:
RTCStatsTimestamp(RTCStatsTimestampState aState, TimeStamp aMozTime);
const RTCStatsTimestampState mState;
const TimeStamp mMozTime;
};
class RTCStatsTimestampMaker {
public:
static RTCStatsTimestampMaker Create(nsPIDOMWindowInner* aWindow = nullptr);
RTCStatsTimestamp GetNow()
const;
const RTCStatsTimestampState mState;
protected:
explicit RTCStatsTimestampMaker(RTCStatsTimestampState aState);
};
// TODO(bug 1588303): If we ever get move semantics for webidl dictionaries, we
// can stop wrapping these in UniquePtr, which will allow us to simplify code
// in several places.
typedef MozPromise<UniquePtr<RTCStatsCollection>, nsresult,
true>
RTCStatsPromise;
typedef MozPromise<UniquePtr<RTCStatsReportInternal>, nsresult,
true>
RTCStatsReportPromise;
class RTCStatsReport final :
public nsWrapperCache {
public:
NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(RTCStatsReport)
NS_DECL_CYCLE_COLLECTION_NATIVE_WRAPPERCACHE_CLASS(RTCStatsReport)
explicit RTCStatsReport(nsPIDOMWindowInner* aParent);
// TODO(bug 1586109): Remove this once we no longer have to create empty
// RTCStatsReports from JS.
static already_AddRefed<RTCStatsReport> Constructor(
const GlobalObject& aGlobal);
void Incorporate(RTCStatsCollection& aStats);
nsPIDOMWindowInner* GetParentObject()
const {
return mParent; }
JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) override;
private:
~RTCStatsReport() =
default;
void Set(
const nsAString& aKey, JS::Handle<JSObject*> aValue,
ErrorResult& aRv);
template <
typename T>
nsresult SetRTCStats(Sequence<T>& aValues) {
for (T& value : aValues) {
nsresult rv = SetRTCStats(value);
if (NS_FAILED(rv)) {
return rv;
}
}
return NS_OK;
}
// We cannot just declare this as SetRTCStats(RTCStats&), because the
// conversion function that ToJSValue uses is non-virtual.
template <
typename T>
nsresult SetRTCStats(T& aValue) {
static_assert(std::is_base_of<RTCStats, T>::value,
"SetRTCStats is for setting RTCStats only");
if (!aValue.mId.WasPassed()) {
return NS_OK;
}
const nsString key(aValue.mId.Value());
// Cargo-culted from dom::Promise; converts aValue to a JSObject
AutoEntryScript aes(mParent->AsGlobal()->GetGlobalJSObject(),
"RTCStatsReport::SetRTCStats");
JSContext* cx = aes.cx();
JS::Rooted<JS::Value> val(cx);
if (!ToJSValue(cx, std::forward<T>(aValue), &val)) {
return NS_ERROR_FAILURE;
}
JS::Rooted<JSObject*> jsObject(cx, &val.toObject());
ErrorResult rv;
Set(key, jsObject, rv);
return rv.StealNSResult();
}
nsCOMPtr<nsPIDOMWindowInner> mParent;
};
void MergeStats(UniquePtr<dom::RTCStatsCollection> aFromStats,
dom::RTCStatsCollection* aIntoStats);
void FlattenStats(nsTArray<UniquePtr<dom::RTCStatsCollection>> aFromStats,
dom::RTCStatsCollection* aIntoStats);
}
// namespace dom
}
// namespace mozilla
#endif // RTCStatsReport_h_
