Bug 1228508 - Part 2, maintain the set of availability objects. r=smaug

MozReview-Commit-ID: 8JNWvnfsMU7

dom/presentation/AvailabilityCollection.cpp

@@ -0,0 +1,99 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "AvailabilityCollection.h"
+
+#include "mozilla/ClearOnShutdown.h"
+#include "PresentationAvailability.h"
+
+namespace mozilla {
+namespace dom {
+
+/* static */
+StaticAutoPtr<AvailabilityCollection>
+AvailabilityCollection::sSingleton;
+static bool gOnceAliveNowDead = false;
+
+/* static */ AvailabilityCollection*
+AvailabilityCollection::GetSingleton()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!sSingleton && !gOnceAliveNowDead) {
+    sSingleton = new AvailabilityCollection();
+    ClearOnShutdown(&sSingleton);
+  }
+
+  return sSingleton;
+}
+
+AvailabilityCollection::AvailabilityCollection()
+{
+  MOZ_COUNT_CTOR(AvailabilityCollection);
+}
+
+AvailabilityCollection::~AvailabilityCollection()
+{
+  MOZ_COUNT_DTOR(AvailabilityCollection);
+  gOnceAliveNowDead = true;
+}
+
+void
+AvailabilityCollection::Add(PresentationAvailability* aAvailability)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!aAvailability) {
+    return;
+  }
+
+  WeakPtr<PresentationAvailability> availability = aAvailability;
+  if (mAvailabilities.Contains(aAvailability)) {
+    return;
+  }
+
+  mAvailabilities.AppendElement(aAvailability);
+}
+
+void
+AvailabilityCollection::Remove(PresentationAvailability* aAvailability)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!aAvailability) {
+    return;
+  }
+
+  WeakPtr<PresentationAvailability> availability = aAvailability;
+  mAvailabilities.RemoveElement(availability);
+}
+
+already_AddRefed<PresentationAvailability>
+AvailabilityCollection::Find(const uint64_t aWindowId, const nsAString& aUrl)
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  // Loop backwards to allow removing elements in the loop.
+  for (int i = mAvailabilities.Length() - 1; i >= 0; --i) {
+    WeakPtr<PresentationAvailability> availability = mAvailabilities[i];
+    if (!availability) {
+      // The availability object was destroyed. Remove it from the list.
+      mAvailabilities.RemoveElementAt(i);
+      continue;
+    }
+
+    if (availability->Equals(aWindowId, aUrl)) {
+      RefPtr<PresentationAvailability> matchedAvailability = availability.get();
+      return matchedAvailability.forget();
+    }
+  }
+
+
+  return nullptr;
+}
+
+} // namespace dom
+} // namespace mozilla