1 files changed, 48 insertions, 0 deletions
diff --git a/dom/media/SelfRef.h b/dom/media/SelfRef.h
new file mode 100644
index 000000000..ca9d0b749
--- /dev/null
+++ b/dom/media/SelfRef.h
@@ -0,0 +1,48 @@
+/* -*- 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 SELF_REF_H
+#define SELF_REF_H
+
+#include "mozilla/Attributes.h"
+
+namespace mozilla {
+
+template<class T>
+class SelfReference {
+public:
+  SelfReference() : mHeld(false) {}
+  ~SelfReference()
+  {
+    NS_ASSERTION(!mHeld, "Forgot to drop the self reference?");
+  }
+
+  void Take(T* t)
+  {
+    if (!mHeld) {
+      mHeld = true;
+      t->AddRef();
+    }
+  }
+  void Drop(T* t)
+  {
+    if (mHeld) {
+      mHeld = false;
+      t->Release();
+    }
+  }
+
+  MOZ_IMPLICIT operator bool() const { return mHeld; }
+
+  SelfReference(const SelfReference& aOther) = delete;
+  void operator=(const SelfReference& aOther) = delete;
+private:
+  bool mHeld;
+};
+
+} // namespace mozilla
+
+#endif // SELF_REF_H