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 "platform/heap/Handle.h"
30#include "wtf/Forward.h"
31#include "wtf/HashMap.h"
32#include "wtf/HashSet.h"
33#include "wtf/text/StringHash.h"
34
35namespace blink {
36
37class IdTargetObserver;
38
39class IdTargetObserverRegistry FINAL : public NoBaseWillBeGarbageCollectedFinalized<IdTargetObserverRegistry> {
40    WTF_MAKE_NONCOPYABLE(IdTargetObserverRegistry);
41    WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
42    friend class IdTargetObserver;
43public:
44    static PassOwnPtrWillBeRawPtr<IdTargetObserverRegistry> create();
45    void trace(Visitor*);
46    void notifyObservers(const AtomicString& id);
47    bool hasObservers(const AtomicString& id) const;
48
49private:
50    IdTargetObserverRegistry() : m_notifyingObserversInSet(nullptr) { }
51    void addObserver(const AtomicString& id, IdTargetObserver*);
52    void removeObserver(const AtomicString& id, IdTargetObserver*);
53    void notifyObserversInternal(const AtomicString& id);
54
55    typedef WillBeHeapHashSet<RawPtrWillBeMember<IdTargetObserver> > ObserverSet;
56    typedef WillBeHeapHashMap<StringImpl*, OwnPtrWillBeMember<ObserverSet> > IdToObserverSetMap;
57    IdToObserverSetMap m_registry;
58    RawPtrWillBeMember<ObserverSet> m_notifyingObserversInSet;
59};
60
61inline void IdTargetObserverRegistry::notifyObservers(const AtomicString& id)
62{
63    ASSERT(!m_notifyingObserversInSet);
64    if (id.isEmpty() || m_registry.isEmpty())
65        return;
66    IdTargetObserverRegistry::notifyObserversInternal(id);
67}
68
69} // namespace blink
70
71#endif // IdTargetObserverRegistry_h
72