common/include/QtCore/qthreadstorage.h

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#ifndef QTHREADSTORAGE_H
#define QTHREADSTORAGE_H

#include <QtCore/qglobal.h>

#ifndef QT_NO_THREAD

QT_BEGIN_NAMESPACE


class Q_CORE_EXPORT QThreadStorageData
{
public:
    explicit QThreadStorageData(void (*func)(void *));
    ~QThreadStorageData();

    void** get() const;
    void** set(void* p);

    static void finish(void**);
    int id;
};

#if !defined(QT_MOC_CPP)
// MOC_SKIP_BEGIN

// pointer specialization
template <typename T>
inline
T *&qThreadStorage_localData(QThreadStorageData &d, T **)
{
    void **v = d.get();
    if (!v) v = d.set(0);
    return *(reinterpret_cast<T**>(v));
}

template <typename T>
inline
T *qThreadStorage_localData_const(const QThreadStorageData &d, T **)
{
    void **v = d.get();
    return v ? *(reinterpret_cast<T**>(v)) : 0;
}

template <typename T>
inline
void qThreadStorage_setLocalData(QThreadStorageData &d, T **t)
{ (void) d.set(*t); }

template <typename T>
inline
void qThreadStorage_deleteData(void *d, T **)
{ delete static_cast<T *>(d); }

// value-based specialization
template <typename T>
inline
T &qThreadStorage_localData(QThreadStorageData &d, T *)
{
    void **v = d.get();
    if (!v) v = d.set(new T());
    return *(reinterpret_cast<T*>(*v));
}

template <typename T>
inline
T qThreadStorage_localData_const(const QThreadStorageData &d, T *)
{
    void **v = d.get();
    return v ? *(reinterpret_cast<T*>(*v)) : T();
}

template <typename T>
inline
void qThreadStorage_setLocalData(QThreadStorageData &d, T *t)
{ (void) d.set(new T(*t)); }

template <typename T>
inline
void qThreadStorage_deleteData(void *d, T *)
{ delete static_cast<T *>(d); }


// MOC_SKIP_END
#endif

template <class T>
class QThreadStorage
{
private:
    QThreadStorageData d;

    Q_DISABLE_COPY(QThreadStorage)

    static inline void deleteData(void *x)
    { qThreadStorage_deleteData(x, reinterpret_cast<T*>(0)); }

public:
    inline QThreadStorage() : d(deleteData) { }
    inline ~QThreadStorage() { }

    inline bool hasLocalData() const
    { return d.get() != 0; }

    inline T& localData()
    { return qThreadStorage_localData(d, reinterpret_cast<T*>(0)); }
    inline T localData() const
    { return qThreadStorage_localData_const(d, reinterpret_cast<T*>(0)); }

    inline void setLocalData(T t)
    { qThreadStorage_setLocalData(d, &t); }
};

QT_END_NAMESPACE

#endif // QT_NO_THREAD

#endif // QTHREADSTORAGE_H