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#ifndef QV8GCCALLBACK_P_H
#define QV8GCCALLBACK_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <QtCore/qobject.h>
#include <QtCore/qthreadstorage.h>
#include <private/qv8_p.h>
#include <private/qintrusivelist_p.h>

QT_BEGIN_NAMESPACE

class Q_AUTOTEST_EXPORT QV8GCCallback
{
private:
    class ThreadData;
public:
    static void garbageCollectorPrologueCallback(v8::GCType, v8::GCCallbackFlags);
    static void registerGcPrologueCallback();

    class Referencer {
    public:
        ~Referencer() {}
        void addRelationship(QObject *object, v8::Persistent<v8::Value> handle);
        void addRelationship(QObject *object, QObject *other);
    private:
        Referencer();
        static v8::Persistent<v8::Object> *findOwnerAndStrength(QObject *qobjectOwner, bool *shouldBeStrong);
        v8::Persistent<v8::Object> strongReferencer;
        friend class QV8GCCallback::ThreadData;
    };

    class Node {
    public:
        typedef void (*PrologueCallback)(Referencer *r, Node *node);
        Node(PrologueCallback callback);
        ~Node();

        QIntrusiveListNode node;
        PrologueCallback prologueCallback;
    };

    static void addGcCallbackNode(Node *node);

private:
    class ThreadData {
    public:
        ThreadData() : gcPrologueCallbackRegistered(false) { }
        ~ThreadData();
        Referencer referencer;
        bool gcPrologueCallbackRegistered;
        QIntrusiveList<Node, &Node::node> gcCallbackNodes;
    };

    static void initializeThreadData();
    static QThreadStorage<ThreadData *> threadData;
};

QT_END_NAMESPACE

#endif // QV8GCCALLBACK_P_H