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39
40#ifndef QREFCOUNT_H
41#define QREFCOUNT_H
42
43#include <QtCore/qatomic.h>
44
45QT_BEGIN_NAMESPACE
46
47
48namespace QtPrivate
49{
50
51class RefCount
52{
53public:
54 inline bool ref() noexcept {
55 int count = atomic.loadRelaxed();
56 if (count != -1) // !isStatic
57 atomic.ref();
58 return true;
59 }
60
61 inline bool deref() noexcept {
62 int count = atomic.loadRelaxed();
63 if (count == -1) // isStatic
64 return true;
65 return atomic.deref();
66 }
67
68 bool isStatic() const noexcept
69 {
70 // Persistent object, never deleted
71 return atomic.loadRelaxed() == -1;
72 }
73
74 bool isShared() const noexcept
75 {
76 int count = atomic.loadRelaxed();
77 return (count != 1) && (count != 0);
78 }
79
80 void initializeOwned() noexcept { atomic.storeRelaxed(1); }
81 void initializeUnsharable() noexcept { atomic.storeRelaxed(0); }
82
83 QBasicAtomicInt atomic;
84};
85
86}
87
88#define Q_REFCOUNT_INITIALIZE_STATIC { Q_BASIC_ATOMIC_INITIALIZER(-1) }
89
90QT_END_NAMESPACE
91
92#endif
93