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diff --git a/src/libs/xpcom18a4/xpcom/glue/nsWeakReference.h b/src/libs/xpcom18a4/xpcom/glue/nsWeakReference.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is the Mozilla browser.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications, Inc.
+ * Portions created by the Initial Developer are Copyright (C) 1999
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Scott Collins <scc@netscape.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef nsWeakReference_h__
+#define nsWeakReference_h__
+
+// nsWeakReference.h
+
+#include "nsIWeakReference.h"
+
+class nsWeakReference;
+
+#undef IMETHOD_VISIBILITY
+#define IMETHOD_VISIBILITY NS_VISIBILITY_DEFAULT
+
+class NS_COM nsSupportsWeakReference : public nsISupportsWeakReference
+ {
+ public:
+ nsSupportsWeakReference()
+ : mProxy(0)
+ {
+ // nothing else to do here
+ }
+
+ NS_DECL_NSISUPPORTSWEAKREFERENCE
+
+ protected:
+ inline ~nsSupportsWeakReference();
+
+ private:
+ friend class nsWeakReference;
+
+ void
+ NoticeProxyDestruction()
+ // ...called (only) by an |nsWeakReference| from _its_ dtor.
+ {
+ mProxy = 0;
+ }
+
+ nsWeakReference* mProxy;
+
+ protected:
+
+ inline void ClearWeakReferences();
+ PRBool HasWeakReferences() const {return mProxy != 0;}
+ };
+
+#undef IMETHOD_VISIBILITY
+#define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN
+
+class NS_COM nsWeakReference : public nsIWeakReference
+ {
+ public:
+ // nsISupports...
+ NS_IMETHOD_(nsrefcnt) AddRef();
+ NS_IMETHOD_(nsrefcnt) Release();
+ NS_IMETHOD QueryInterface( const nsIID&, void** );
+
+ // nsIWeakReference...
+ NS_DECL_NSIWEAKREFERENCE
+
+ private:
+ friend class nsSupportsWeakReference;
+
+ nsWeakReference( nsSupportsWeakReference* referent )
+ : mRefCount(0),
+ mReferent(referent)
+ // ...I can only be constructed by an |nsSupportsWeakReference|
+ {
+ // nothing else to do here
+ }
+
+ ~nsWeakReference()
+ // ...I will only be destroyed by calling |delete| myself.
+ {
+ if ( mReferent )
+ mReferent->NoticeProxyDestruction();
+ }
+
+ void
+ NoticeReferentDestruction()
+ // ...called (only) by an |nsSupportsWeakReference| from _its_ dtor.
+ {
+ mReferent = 0;
+ }
+
+ nsrefcnt mRefCount;
+ nsSupportsWeakReference* mReferent;
+ };
+
+inline
+void
+nsSupportsWeakReference::ClearWeakReferences()
+ /*
+ Usually being called from |nsSupportsWeakReference::~nsSupportsWeakReference|
+ will be good enough, but you may have a case where you need to call disconnect
+ your weak references in an outer destructor (to prevent some client holding a
+ weak reference from re-entering your destructor).
+ */
+ {
+ if ( mProxy )
+ {
+ mProxy->NoticeReferentDestruction();
+ mProxy = 0;
+ }
+ }
+
+inline
+nsSupportsWeakReference::~nsSupportsWeakReference()
+ {
+ ClearWeakReferences();
+ }
+
+#endif