summaryrefslogtreecommitdiffstats
path: root/xpcom/base/nsWeakReference.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--xpcom/base/nsWeakReference.h68
1 files changed, 68 insertions, 0 deletions
diff --git a/xpcom/base/nsWeakReference.h b/xpcom/base/nsWeakReference.h
new file mode 100644
index 0000000000..5303f2d2ea
--- /dev/null
+++ b/xpcom/base/nsWeakReference.h
@@ -0,0 +1,68 @@
+/* -*- 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 nsWeakReference_h__
+#define nsWeakReference_h__
+
+// nsWeakReference.h
+
+// See mfbt/WeakPtr.h for a more typesafe C++ implementation of weak references
+
+#include "nsIWeakReferenceUtils.h"
+
+class nsWeakReference;
+
+class nsSupportsWeakReference : public nsISupportsWeakReference {
+ public:
+ nsSupportsWeakReference() : mProxy(0) {}
+
+ NS_DECL_NSISUPPORTSWEAKREFERENCE
+
+ protected:
+ inline ~nsSupportsWeakReference();
+
+ private:
+ friend class nsWeakReference;
+
+ // Called (only) by an |nsWeakReference| from _its_ dtor.
+ // The thread safety check is made by the caller.
+ void NoticeProxyDestruction() { mProxy = nullptr; }
+
+ nsWeakReference* MOZ_NON_OWNING_REF mProxy;
+
+ protected:
+ void ClearWeakReferences();
+ bool HasWeakReferences() const { return !!mProxy; }
+};
+
+inline nsSupportsWeakReference::~nsSupportsWeakReference() {
+ ClearWeakReferences();
+}
+
+#define NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE \
+ tmp->ClearWeakReferences();
+
+#define NS_IMPL_CYCLE_COLLECTION_WEAK(class_, ...) \
+ NS_IMPL_CYCLE_COLLECTION_CLASS(class_) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(class_) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK(__VA_ARGS__) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_END \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(class_) \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE(__VA_ARGS__) \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+#define NS_IMPL_CYCLE_COLLECTION_WEAK_INHERITED(class_, super_, ...) \
+ NS_IMPL_CYCLE_COLLECTION_CLASS(class_) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(class_, super_) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK(__VA_ARGS__) \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE \
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_END \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(class_, super_) \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE(__VA_ARGS__) \
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+#endif