1 files changed, 105 insertions, 0 deletions
diff --git a/dom/media/eme/DetailedPromise.cpp b/dom/media/eme/DetailedPromise.cpp
new file mode 100644
index 000000000..5893bea2e
--- /dev/null
+++ b/dom/media/eme/DetailedPromise.cpp
@@ -0,0 +1,105 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 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 http://mozilla.org/MPL/2.0/. */
+
+#include "DetailedPromise.h"
+#include "mozilla/dom/DOMException.h"
+#include "nsPrintfCString.h"
+
+namespace mozilla {
+namespace dom {
+
+DetailedPromise::DetailedPromise(nsIGlobalObject* aGlobal,
+                                 const nsACString& aName)
+  : Promise(aGlobal)
+  , mName(aName)
+  , mResponded(false)
+  , mStartTime(TimeStamp::Now())
+{
+}
+
+DetailedPromise::DetailedPromise(nsIGlobalObject* aGlobal,
+                                 const nsACString& aName,
+                                 Telemetry::ID aSuccessLatencyProbe,
+                                 Telemetry::ID aFailureLatencyProbe)
+  : DetailedPromise(aGlobal, aName)
+{
+  mSuccessLatencyProbe.Construct(aSuccessLatencyProbe);
+  mFailureLatencyProbe.Construct(aFailureLatencyProbe);
+}
+
+DetailedPromise::~DetailedPromise()
+{
+  // It would be nice to assert that mResponded is identical to
+  // GetPromiseState() == PromiseState::Rejected.  But by now we've been
+  // unlinked, so don't have a reference to our actual JS Promise object
+  // anymore.
+  MaybeReportTelemetry(Failed);
+}
+
+void
+DetailedPromise::MaybeReject(nsresult aArg, const nsACString& aReason)
+{
+  nsPrintfCString msg("%s promise rejected 0x%x '%s'", mName.get(), aArg,
+                      PromiseFlatCString(aReason).get());
+  EME_LOG(msg.get());
+
+  MaybeReportTelemetry(Failed);
+
+  LogToBrowserConsole(NS_ConvertUTF8toUTF16(msg));
+
+  ErrorResult rv;
+  rv.ThrowDOMException(aArg, aReason);
+  Promise::MaybeReject(rv);
+}
+
+void
+DetailedPromise::MaybeReject(ErrorResult&, const nsACString& aReason)
+{
+  NS_NOTREACHED("nsresult expected in MaybeReject()");
+}
+
+/* static */ already_AddRefed<DetailedPromise>
+DetailedPromise::Create(nsIGlobalObject* aGlobal,
+                        ErrorResult& aRv,
+                        const nsACString& aName)
+{
+  RefPtr<DetailedPromise> promise = new DetailedPromise(aGlobal, aName);
+  promise->CreateWrapper(nullptr, aRv);
+  return aRv.Failed() ? nullptr : promise.forget();
+}
+
+/* static */ already_AddRefed<DetailedPromise>
+DetailedPromise::Create(nsIGlobalObject* aGlobal,
+                        ErrorResult& aRv,
+                        const nsACString& aName,
+                        Telemetry::ID aSuccessLatencyProbe,
+                        Telemetry::ID aFailureLatencyProbe)
+{
+  RefPtr<DetailedPromise> promise = new DetailedPromise(aGlobal, aName, aSuccessLatencyProbe, aFailureLatencyProbe);
+  promise->CreateWrapper(nullptr, aRv);
+  return aRv.Failed() ? nullptr : promise.forget();
+}
+
+void
+DetailedPromise::MaybeReportTelemetry(Status aStatus)
+{
+  if (mResponded) {
+    return;
+  }
+  mResponded = true;
+  if (!mSuccessLatencyProbe.WasPassed() || !mFailureLatencyProbe.WasPassed()) {
+    return;
+  }
+  uint32_t latency = (TimeStamp::Now() - mStartTime).ToMilliseconds();
+  EME_LOG("%s %s latency %ums reported via telemetry", mName.get(),
+          ((aStatus == Succeeded) ? "succcess" : "failure"), latency);
+  Telemetry::ID tid = (aStatus == Succeeded) ? mSuccessLatencyProbe.Value()
+                                             : mFailureLatencyProbe.Value();
+  Telemetry::Accumulate(tid, latency);
+}
+
+} // namespace dom
+} // namespace mozilla