1 files changed, 45 insertions, 0 deletions
diff --git a/gfx/layers/ipc/ActiveResource.h b/gfx/layers/ipc/ActiveResource.h
new file mode 100644
index 0000000000..6e7db60541
--- /dev/null
+++ b/gfx/layers/ipc/ActiveResource.h
@@ -0,0 +1,45 @@
+/* -*- 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 http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_LAYERS_ACTIVERESOURCE
+#define MOZILLA_LAYERS_ACTIVERESOURCE
+
+#include "nsExpirationTracker.h"
+
+namespace mozilla::layers {
+
+/**
+ * See ActiveResourceTracker below.
+ */
+class ActiveResource {
+ public:
+  virtual void NotifyInactive() = 0;
+  nsExpirationState* GetExpirationState() { return &mExpirationState; }
+  bool IsActivityTracked() { return mExpirationState.IsTracked(); }
+
+ private:
+  nsExpirationState mExpirationState;
+};
+
+/**
+ * A convenience class on top of nsExpirationTracker
+ */
+class ActiveResourceTracker final
+    : public nsExpirationTracker<ActiveResource, 3> {
+ public:
+  ActiveResourceTracker(uint32_t aExpirationCycle, const char* aName,
+                        nsIEventTarget* aEventTarget)
+      : nsExpirationTracker(aExpirationCycle, aName, aEventTarget) {}
+
+  void NotifyExpired(ActiveResource* aResource) override {
+    RemoveObject(aResource);
+    aResource->NotifyInactive();
+  }
+};
+
+}  // namespace mozilla::layers
+
+#endif