1/*
2 * Copyright (C) 2012 Google Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef IdTargetObserverRegistry_h
27#define IdTargetObserverRegistry_h
28
29#include <memory>
30#include <wtf/Forward.h>
31#include <wtf/HashMap.h>
32#include <wtf/HashSet.h>
33#include <wtf/text/AtomicString.h>
34
35namespace WebCore {
36
37class IdTargetObserver;
38
39class IdTargetObserverRegistry {
40    WTF_MAKE_FAST_ALLOCATED;
41    friend class IdTargetObserver;
42public:
43    IdTargetObserverRegistry()
44        : m_notifyingObserversInSet(0)
45    { }
46
47    void notifyObservers(const AtomicString& id);
48    void notifyObservers(const AtomicStringImpl& id);
49
50private:
51    void addObserver(const AtomicString& id, IdTargetObserver*);
52    void removeObserver(const AtomicString& id, IdTargetObserver*);
53    void notifyObserversInternal(const AtomicStringImpl& id);
54
55    typedef HashSet<IdTargetObserver*> ObserverSet;
56    typedef HashMap<const AtomicStringImpl*, std::unique_ptr<ObserverSet>> IdToObserverSetMap;
57    IdToObserverSetMap m_registry;
58    ObserverSet* m_notifyingObserversInSet;
59};
60
61inline void IdTargetObserverRegistry::notifyObservers(const AtomicString& id)
62{
63    if (!id.isEmpty())
64        return notifyObservers(*id.impl());
65}
66
67inline void IdTargetObserverRegistry::notifyObservers(const AtomicStringImpl& id)
68{
69    ASSERT(!m_notifyingObserversInSet);
70    ASSERT(id.length());
71    if (m_registry.isEmpty())
72        return;
73    IdTargetObserverRegistry::notifyObserversInternal(id);
74}
75
76} // namespace WebCore
77
78#endif // IdTargetObserverRegistry_h
79