1 files changed, 155 insertions, 0 deletions
diff --git a/dom/media/webrtc/jsapi/RTCStatsReport.h b/dom/media/webrtc/jsapi/RTCStatsReport.h
new file mode 100644
index 0000000000..5319f26e6b
--- /dev/null
+++ b/dom/media/webrtc/jsapi/RTCStatsReport.h
@@ -0,0 +1,155 @@
+/* -*- 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 {
+
+/**
+ * Class that facilitates creating timestamps for webrtc stats by mimicking
+ * dom::Performance, as well as getting and converting timestamps for libwebrtc
+ * and our integration with it.
+ *
+ * It converts and uses time from these clocks:
+ * - 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().
+ * - WallClock: Non-monotonic, unix epoch.
+ */
+class RTCStatsTimestampMaker {
+ public:
+  RTCStatsTimestampMaker();
+  explicit RTCStatsTimestampMaker(nsPIDOMWindowInner* aWindow);
+
+  DOMHighResTimeStamp GetNow() const;
+
+  webrtc::Timestamp GetNowRealtime() const;
+  webrtc::Timestamp ConvertMozTimeToRealtime(TimeStamp aMozTime) const;
+  webrtc::Timestamp ConvertRealtimeTo1Jan1970(
+      webrtc::Timestamp aRealtime) const;
+  DOMHighResTimeStamp ConvertNtpToDomTime(webrtc::Timestamp aNtpTime) const;
+  DOMHighResTimeStamp ReduceRealtimePrecision(
+      webrtc::Timestamp aRealtime) const;
+
+  const uint64_t mRandomTimelineSeed;
+  const TimeStamp mStartRealtime;
+  const RTPCallerType mRTPCallerType;
+  const DOMHighResTimeStamp mStartWallClockRaw;
+};
+
+// 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_