1 files changed, 140 insertions, 0 deletions
diff --git a/dom/media/utils/MediaElementEventRunners.cpp b/dom/media/utils/MediaElementEventRunners.cpp
new file mode 100644
index 0000000000..57be04528c
--- /dev/null
+++ b/dom/media/utils/MediaElementEventRunners.cpp
@@ -0,0 +1,140 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+#include "MediaElementEventRunners.h"
+
+#include "mozilla/dom/HTMLMediaElement.h"
+
+extern mozilla::LazyLogModule gMediaElementEventsLog;
+#define LOG_EVENT(type, msg) MOZ_LOG(gMediaElementEventsLog, type, msg)
+
+namespace mozilla::dom {
+
+nsMediaEventRunner::nsMediaEventRunner(const nsAString& aName,
+                                       HTMLMediaElement* aElement,
+                                       const nsAString& aEventName)
+    : mElement(aElement),
+      mName(aName),
+      mEventName(aEventName),
+      mLoadID(mElement->GetCurrentLoadID()) {}
+
+bool nsMediaEventRunner::IsCancelled() {
+  return !mElement || mElement->GetCurrentLoadID() != mLoadID;
+}
+
+nsresult nsMediaEventRunner::DispatchEvent(const nsAString& aName) {
+  return mElement ? mElement->DispatchEvent(aName) : NS_OK;
+}
+
+NS_IMPL_CYCLE_COLLECTION(nsMediaEventRunner, mElement)
+NS_IMPL_CYCLE_COLLECTING_ADDREF(nsMediaEventRunner)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(nsMediaEventRunner)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsMediaEventRunner)
+  NS_INTERFACE_MAP_ENTRY(nsINamed)
+  NS_INTERFACE_MAP_ENTRY(nsIRunnable)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIRunnable)
+NS_INTERFACE_MAP_END
+
+NS_IMETHODIMP nsAsyncEventRunner::Run() {
+  // Silently cancel if our load has been cancelled or element has been CCed.
+  return IsCancelled() ? NS_OK : DispatchEvent(mEventName);
+}
+
+nsResolveOrRejectPendingPlayPromisesRunner::
+    nsResolveOrRejectPendingPlayPromisesRunner(
+        HTMLMediaElement* aElement, nsTArray<RefPtr<PlayPromise>>&& aPromises,
+        nsresult aError)
+    : nsMediaEventRunner(u"nsResolveOrRejectPendingPlayPromisesRunner"_ns,
+                         aElement),
+      mPromises(std::move(aPromises)),
+      mError(aError) {
+  mElement->mPendingPlayPromisesRunners.AppendElement(this);
+}
+
+void nsResolveOrRejectPendingPlayPromisesRunner::ResolveOrReject() {
+  if (NS_SUCCEEDED(mError)) {
+    PlayPromise::ResolvePromisesWithUndefined(mPromises);
+  } else {
+    PlayPromise::RejectPromises(mPromises, mError);
+  }
+}
+
+NS_IMETHODIMP nsResolveOrRejectPendingPlayPromisesRunner::Run() {
+  if (!IsCancelled()) {
+    ResolveOrReject();
+  }
+
+  mElement->mPendingPlayPromisesRunners.RemoveElement(this);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsNotifyAboutPlayingRunner::Run() {
+  if (!IsCancelled()) {
+    DispatchEvent(u"playing"_ns);
+  }
+  return nsResolveOrRejectPendingPlayPromisesRunner::Run();
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(nsResolveOrRejectPendingPlayPromisesRunner,
+                                   nsMediaEventRunner, mPromises)
+NS_IMPL_ADDREF_INHERITED(nsResolveOrRejectPendingPlayPromisesRunner,
+                         nsMediaEventRunner)
+NS_IMPL_RELEASE_INHERITED(nsResolveOrRejectPendingPlayPromisesRunner,
+                          nsMediaEventRunner)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(
+    nsResolveOrRejectPendingPlayPromisesRunner)
+NS_INTERFACE_MAP_END_INHERITING(nsMediaEventRunner)
+
+NS_IMETHODIMP nsSourceErrorEventRunner::Run() {
+  // Silently cancel if our load has been cancelled.
+  if (IsCancelled()) {
+    return NS_OK;
+  }
+  LOG_EVENT(LogLevel::Debug,
+            ("%p Dispatching simple event source error", mElement.get()));
+  return nsContentUtils::DispatchTrustedEvent(mElement->OwnerDoc(), mSource,
+                                              u"error"_ns, CanBubble::eNo,
+                                              Cancelable::eNo);
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(nsSourceErrorEventRunner, nsMediaEventRunner,
+                                   mSource)
+NS_IMPL_ADDREF_INHERITED(nsSourceErrorEventRunner, nsMediaEventRunner)
+NS_IMPL_RELEASE_INHERITED(nsSourceErrorEventRunner, nsMediaEventRunner)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsSourceErrorEventRunner)
+NS_INTERFACE_MAP_END_INHERITING(nsMediaEventRunner)
+
+NS_IMETHODIMP nsTimeupdateRunner::Run() {
+  if (IsCancelled() || !ShouldDispatchTimeupdate()) {
+    return NS_OK;
+  }
+  // After dispatching `timeupdate`, if the timeupdate event listener takes lots
+  // of time then we end up spending all time handling just timeupdate events.
+  // The spec is vague in this situation, so we choose to update time after we
+  // dispatch the event in order to solve that issue.
+  nsresult rv = DispatchEvent(mEventName);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    LOG_EVENT(LogLevel::Debug,
+              ("%p Failed to dispatch 'timeupdate'", mElement.get()));
+  } else {
+    mElement->UpdateLastTimeupdateDispatchTime();
+  }
+  return rv;
+}
+
+bool nsTimeupdateRunner::ShouldDispatchTimeupdate() const {
+  if (mIsMandatory) {
+    return true;
+  }
+
+  // If the main thread is busy, tasks may be delayed and dispatched at
+  // unexpected times. Ensure we don't dispatch `timeupdate` more often
+  // than once per `TIMEUPDATE_MS`.
+  const TimeStamp& lastTime = mElement->LastTimeupdateDispatchTime();
+  return lastTime.IsNull() || TimeStamp::Now() - lastTime >
+                                  TimeDuration::FromMilliseconds(TIMEUPDATE_MS);
+}
+
+#undef LOG_EVENT
+}  // namespace mozilla::dom