1/*
2 * Copyright (C) 2013 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 are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef GCObservation_h
32#define GCObservation_h
33
34#include "bindings/v8/ScopedPersistent.h"
35#include "wtf/PassRefPtr.h"
36#include "wtf/RefCounted.h"
37#include <v8.h>
38
39namespace WebCore {
40
41class GCObservation : public RefCounted<GCObservation> {
42public:
43    static PassRefPtr<GCObservation> create(v8::Handle<v8::Value> observedValue) { return adoptRef(new GCObservation(observedValue)); }
44    ~GCObservation() { }
45
46    // Caution: It is only feasible to determine whether an object was
47    // "near death"; it may have been kept alive through a weak
48    // handle. After reaching near-death, having been collected is the
49    // common case.
50    bool wasCollected() const { return m_collected; }
51    void setWasCollected();
52
53private:
54    explicit GCObservation(v8::Handle<v8::Value>);
55
56    ScopedPersistent<v8::Value> m_observed;
57    bool m_collected;
58};
59
60}
61
62#endif // GCObservation_h
63