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39
40#ifndef QT3DCORE_QHANDLE_P_H
41#define QT3DCORE_QHANDLE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of other Qt classes. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <Qt3DCore/qt3dcore_global.h>
55#include <QtCore/QDebug>
56#include <QtCore/qhashfunctions.h>
57
58QT_BEGIN_NAMESPACE
59
60namespace Qt3DCore {
61
62template <typename T>
63class QHandle
64{
65public:
66 struct Data {
67 union {
68 quintptr counter;
69 Data *nextFree;
70 };
71 };
72 QHandle()
73 : d(nullptr),
74 counter(0)
75 {}
76 QHandle(Data *d)
77 : d(d),
78 counter(d->counter)
79 {
80 }
81 QHandle(const QHandle &other)
82 : d(other.d),
83 counter(other.counter)
84 {
85 }
86 QHandle &operator=(const QHandle &other)
87 {
88 d = other.d;
89 counter = other.counter;
90 return *this;
91 }
92
93 inline T *operator->() const;
94 T *data() const;
95
96 quintptr handle() const { return reinterpret_cast<quintptr>(d); }
97 bool isNull() const { return !d; }
98
99 Data *data_ptr() const { return d; }
100
101 bool operator==(const QHandle &other) const { return d == other.d && counter == other.counter; }
102 bool operator!=(const QHandle &other) const { return !operator==(other); }
103private:
104 Data *d;
105 quintptr counter;
106};
107
108
109template <typename T>
110QDebug operator<<(QDebug dbg, const QHandle<T> &h)
111{
112 QDebugStateSaver saver(dbg);
113 QString binNumber = QString::number(h.handle(), 2).rightJustified(32, QChar::fromLatin1(c: '0'));
114 dbg.nospace() << " m_handle = " << h.handle()
115 << " = " << binNumber;
116 return dbg;
117}
118
119template <typename T>
120uint qHash(const QHandle<T> &h, uint seed)
121{
122 using QT_PREPEND_NAMESPACE(qHash);
123 return qHash(h.handle(), seed);
124}
125
126} // Qt3DCore
127
128// simpler than fighting the Q_DECLARE_TYPEINFO macro, use QString as a dummy to get movable semantics
129template <typename T>
130class QTypeInfo<Qt3DCore::QHandle<T> >
131 : public QTypeInfoMerger<Qt3DCore::QHandle<T>, QString> {};
132
133QT_END_NAMESPACE
134
135#endif // QT3DCORE_QRHANDLE_H
136

source code of qt3d/src/core/resources/qhandle_p.h