| 1 | // Copyright (C) 2020 The Qt Company Ltd. |
|---|---|
| 2 | // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only |
| 3 | |
| 4 | #ifndef QQMLGUARDEDCONTEXTDATA_P_H |
| 5 | #define QQMLGUARDEDCONTEXTDATA_P_H |
| 6 | |
| 7 | // |
| 8 | // W A R N I N G |
| 9 | // ------------- |
| 10 | // |
| 11 | // This file is not part of the Qt API. It exists purely as an |
| 12 | // implementation detail. This header file may change from version to |
| 13 | // version without notice, or even be removed. |
| 14 | // |
| 15 | // We mean it. |
| 16 | // |
| 17 | |
| 18 | #include <QtQml/private/qtqmlglobal_p.h> |
| 19 | #include <QtQml/private/qqmlcontextdata_p.h> |
| 20 | |
| 21 | QT_BEGIN_NAMESPACE |
| 22 | |
| 23 | class QQmlGuardedContextData |
| 24 | { |
| 25 | Q_DISABLE_COPY(QQmlGuardedContextData); |
| 26 | public: |
| 27 | QQmlGuardedContextData() = default; |
| 28 | ~QQmlGuardedContextData() { unlink(); } |
| 29 | |
| 30 | QQmlGuardedContextData(QQmlGuardedContextData &&) = default; |
| 31 | QQmlGuardedContextData &operator=(QQmlGuardedContextData &&) = default; |
| 32 | |
| 33 | QQmlGuardedContextData(QQmlRefPointer<QQmlContextData> data) |
| 34 | { |
| 35 | setContextData(std::move(data)); |
| 36 | } |
| 37 | |
| 38 | QQmlGuardedContextData &operator=(QQmlRefPointer<QQmlContextData> d) |
| 39 | { |
| 40 | setContextData(std::move(d)); |
| 41 | return *this; |
| 42 | } |
| 43 | |
| 44 | QQmlRefPointer<QQmlContextData> contextData() const { return m_contextData; } |
| 45 | void setContextData(QQmlRefPointer<QQmlContextData> contextData) |
| 46 | { |
| 47 | if (m_contextData.data() == contextData.data()) |
| 48 | return; |
| 49 | unlink(); |
| 50 | |
| 51 | if (contextData) { |
| 52 | m_contextData = std::move(contextData); |
| 53 | m_next = m_contextData->m_contextGuards; |
| 54 | if (m_next) |
| 55 | m_next->m_prev = &m_next; |
| 56 | |
| 57 | m_contextData->m_contextGuards = this; |
| 58 | m_prev = &m_contextData->m_contextGuards; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | bool isNull() const { return !m_contextData; } |
| 63 | |
| 64 | operator const QQmlRefPointer<QQmlContextData> &() const { return m_contextData; } |
| 65 | QQmlContextData &operator*() const { return m_contextData.operator*(); } |
| 66 | QQmlContextData *operator->() const { return m_contextData.operator->(); } |
| 67 | |
| 68 | QQmlGuardedContextData *next() const { return m_next; } |
| 69 | |
| 70 | private: |
| 71 | void reset() |
| 72 | { |
| 73 | m_contextData.reset(); |
| 74 | m_next = nullptr; |
| 75 | m_prev = nullptr; |
| 76 | } |
| 77 | |
| 78 | void unlink() |
| 79 | { |
| 80 | if (m_prev) { |
| 81 | *m_prev = m_next; |
| 82 | if (m_next) |
| 83 | m_next->m_prev = m_prev; |
| 84 | reset(); |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | QQmlRefPointer<QQmlContextData> m_contextData; |
| 89 | QQmlGuardedContextData *m_next = nullptr; |
| 90 | QQmlGuardedContextData **m_prev = nullptr; |
| 91 | }; |
| 92 | |
| 93 | QT_END_NAMESPACE |
| 94 | |
| 95 | #endif // QQMLGUARDEDCONTEXTDATA_P_H |
| 96 |