| 1 | // Copyright (C) 2016 The Qt Company Ltd. |
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| 2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
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| 3 | |
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| 4 | #ifndef QREFCOUNT_H |
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| 5 | #define QREFCOUNT_H |
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| 6 | |
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| 7 | #include <QtCore/qatomic.h> |
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| 8 | |
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| 9 | QT_BEGIN_NAMESPACE |
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| 10 | |
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| 11 | |
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| 12 | namespace QtPrivate |
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| 13 | { |
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| 14 | |
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| 15 | class RefCount |
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| 16 | { |
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| 17 | public: |
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| 18 | inline bool ref() noexcept { |
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| 19 | int count = atomic.loadRelaxed(); |
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| 20 | if (count != -1) // !isStatic |
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| 21 | atomic.ref(); |
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| 22 | return true; |
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| 23 | } |
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| 24 | |
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| 25 | inline bool deref() noexcept { |
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| 26 | int count = atomic.loadRelaxed(); |
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| 27 | if (count == -1) // isStatic |
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| 28 | return true; |
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| 29 | return atomic.deref(); |
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| 30 | } |
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| 31 | |
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| 32 | bool isStatic() const noexcept |
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| 33 | { |
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| 34 | // Persistent object, never deleted |
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| 35 | return atomic.loadRelaxed() == -1; |
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| 36 | } |
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| 37 | |
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| 38 | bool isShared() const noexcept |
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| 39 | { |
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| 40 | int count = atomic.loadRelaxed(); |
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| 41 | return (count != 1) && (count != 0); |
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| 42 | } |
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| 43 | |
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| 44 | void initializeOwned() noexcept { atomic.storeRelaxed(newValue: 1); } |
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| 45 | void initializeUnsharable() noexcept { atomic.storeRelaxed(newValue: 0); } |
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| 46 | |
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| 47 | QBasicAtomicInt atomic; |
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| 48 | }; |
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| 49 | |
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| 50 | } |
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| 51 | |
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| 52 | #define Q_REFCOUNT_INITIALIZE_STATIC { Q_BASIC_ATOMIC_INITIALIZER(-1) } |
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| 53 | |
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| 54 | QT_END_NAMESPACE |
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| 55 | |
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| 56 | #endif |
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| 57 | |
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