Home | History | Annotate | Download | only in dom
      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 
     35 namespace blink {
     36 
     37 class IdTargetObserver;
     38 
     39 class IdTargetObserverRegistry FINAL : public NoBaseWillBeGarbageCollectedFinalized<IdTargetObserverRegistry> {
     40     WTF_MAKE_NONCOPYABLE(IdTargetObserverRegistry);
     41     WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
     42     friend class IdTargetObserver;
     43 public:
     44     static PassOwnPtrWillBeRawPtr<IdTargetObserverRegistry> create();
     45     void trace(Visitor*);
     46     void notifyObservers(const AtomicString& id);
     47     bool hasObservers(const AtomicString& id) const;
     48 
     49 private:
     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 
     61 inline 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