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diff --git a/include/svl/broadcast.hxx b/include/svl/broadcast.hxx
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * 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/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 .
+ */
+#ifndef INCLUDED_SVL_BROADCAST_HXX
+#define INCLUDED_SVL_BROADCAST_HXX
+
+#include <svl/svldllapi.h>
+
+#include <vector>
+
+class SvtListener;
+class SfxHint;
+
+class SVL_DLLPUBLIC SvtBroadcaster
+{
+public:
+    friend class SvtListener;
+
+    typedef std::vector<SvtListener*> ListenersType;
+
+private:
+    const SvtBroadcaster&   operator=(const SvtBroadcaster &) = delete;
+
+    /**
+     * Ensure that the container doesn't contain any duplicated listener
+     * entries. As a side effect, the listeners get sorted by pointer values
+     * after this call.
+     */
+    void Normalize() const;
+
+    void Add( SvtListener* p );
+    void Remove( SvtListener* p );
+
+protected:
+    virtual void            ListenersGone();
+
+public:
+                            SvtBroadcaster()
+                                : mnEmptySlots(0), mnListenersFirstUnsorted(0), mbAboutToDie(false)
+                                , mbDisposing(false), mbDestNormalized(true) {}
+                            SvtBroadcaster( const SvtBroadcaster &rBC );
+    virtual                 ~SvtBroadcaster();
+
+    void                    Broadcast( const SfxHint &rHint );
+
+    ListenersType& GetAllListeners();
+    const ListenersType& GetAllListeners() const;
+
+    bool HasListeners() const { return (maListeners.size() - mnEmptySlots) > 0; }
+
+    /**
+     * Listeners and broadcasters are M:N relationship.  If you want to
+     * destruct them, you easily end up in O(M*N) situation; where for every
+     * listener, you iterate all broadcasters, to remove that one listener.
+     *
+     * To avoid that, use this call to announce to the broadcaster it is going
+     * to die, and the listeners do not have to bother with removing
+     * themselves from the broadcaster - the broadcaster will not broadcast
+     * anything after the PrepareForDestruction() call anyway.
+     */
+    void PrepareForDestruction();
+
+private:
+    /// contains only one of each listener, which is enforced by SvtListener
+    mutable ListenersType maListeners;
+
+    /// When the broadcaster is about to die, collect listeners that asked for removal.
+    mutable ListenersType maDestructedListeners;
+
+    /**
+        Note that this class is very performance sensitive, so the following fields have been
+        carefully sized and packed so we can access them quickly, while also taking as little CPU cache
+        space as possible (because e.g. calc can have a LOT of them)
+    */
+    mutable sal_Int32 mnEmptySlots;
+    // The first item in maListeners that is not sorted. The container can become large, so this optimizes sorting.
+    mutable sal_Int32 mnListenersFirstUnsorted;
+    /// Indicate that this broadcaster will be destructed (we indicate this on all ScColumn's broadcasters during the ScTable destruction, eg.)
+    bool mbAboutToDie:1;
+    bool mbDisposing:1;
+    // Whether maDestructedListeners is sorted or not.
+    mutable bool mbDestNormalized:1;
+};
+
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */