import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

xpcom/threads/LeakRefPtr.h

@@ -0,0 +1,52 @@
+/* -*- 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/. */
+
+/* Smart pointer which leaks its owning refcounted object by default. */
+
+#ifndef LeakRefPtr_h
+#define LeakRefPtr_h
+
+#include "mozilla/AlreadyAddRefed.h"
+
+namespace mozilla {
+
+/**
+ * Instance of this class behaves like a raw pointer which leaks the
+ * resource it's owning if not explicitly released.
+ */
+template<class T>
+class LeakRefPtr
+{
+public:
+  explicit LeakRefPtr(already_AddRefed<T>&& aPtr)
+    : mRawPtr(aPtr.take()) { }
+
+  explicit operator bool() const { return !!mRawPtr; }
+
+  LeakRefPtr<T>& operator=(already_AddRefed<T>&& aPtr)
+  {
+    mRawPtr = aPtr.take();
+    return *this;
+  }
+
+  T* get() const { return mRawPtr; }
+
+  already_AddRefed<T> take()
+  {
+    T* rawPtr = mRawPtr;
+    mRawPtr = nullptr;
+    return already_AddRefed<T>(rawPtr);
+  }
+
+  void release() { NS_RELEASE(mRawPtr); }
+
+private:
+  T* MOZ_OWNING_REF mRawPtr;
+};
+
+} // namespace mozilla
+
+#endif // LeakRefPtr_h