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 RefCountedSupplement_h
27#define RefCountedSupplement_h
28
29#include "Supplementable.h"
30#include <wtf/RefCounted.h>
31#include <wtf/RefPtr.h>
32
33namespace WebCore {
34
35template<class T, class S>
36class RefCountedSupplement : public RefCounted<S> {
37public:
38    typedef RefCountedSupplement<T, S> ThisType;
39
40    virtual ~RefCountedSupplement() { }
41    virtual void hostDestroyed() { }
42
43    class Wrapper : public Supplement<T> {
44    public:
45        explicit Wrapper(PassRefPtr<ThisType> wrapped) : m_wrapped(wrapped) { }
46        virtual ~Wrapper() { m_wrapped->hostDestroyed();  }
47#if !ASSERT_DISABLED || defined(ADDRESS_SANITIZER)
48        virtual bool isRefCountedWrapper() const override { return true; }
49#endif
50        ThisType* wrapped() const { return m_wrapped.get(); }
51    private:
52
53        RefPtr<ThisType> m_wrapped;
54    };
55
56    static void provideTo(Supplementable<T>* host, const char* key, PassRefPtr<ThisType> supplement)
57    {
58        host->provideSupplement(key, adoptPtr(new Wrapper(supplement)));
59    }
60
61    static ThisType* from(Supplementable<T>* host, const char* key)
62    {
63        Supplement<T>* found = host->requireSupplement(key);
64        if (!found)
65            return 0;
66        ASSERT_WITH_SECURITY_IMPLICATION(found->isRefCountedWrapper());
67        return static_cast<Wrapper*>(found)->wrapped();
68    }
69};
70
71} // namespace WebCore
72
73#endif // RefCountedSupplement_h
74