1/****************************************************************************
2**
3** Copyright (C) 2018 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Sérgio Martins <sergio.martins@kdab.com>
4** Copyright (C) 2019 The Qt Company Ltd.
5** Contact: https://www.qt.io/licensing/
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18** GNU Lesser General Public License Usage
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23** ensure the GNU Lesser General Public License version 3 requirements
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39****************************************************************************/
40
41#ifndef QSCOPEGUARD_H
42#define QSCOPEGUARD_H
43
44#include <QtCore/qglobal.h>
45
46#include <type_traits>
47#include <utility>
48
49QT_BEGIN_NAMESPACE
50
51template <typename F>
52class [[nodiscard]] QScopeGuard
53{
54public:
55 explicit QScopeGuard(F &&f) noexcept
56 : m_func(std::move(f))
57 {
58 }
59
60 explicit QScopeGuard(const F &f) noexcept
61 : m_func(f)
62 {
63 }
64
65 QScopeGuard(QScopeGuard &&other) noexcept
66 : m_func(std::move(other.m_func))
67 , m_invoke(qExchange(other.m_invoke, false))
68 {
69 }
70
71 ~QScopeGuard() noexcept
72 {
73 if (m_invoke)
74 m_func();
75 }
76
77 void dismiss() noexcept
78 {
79 m_invoke = false;
80 }
81
82private:
83 Q_DISABLE_COPY(QScopeGuard)
84
85 F m_func;
86 bool m_invoke = true;
87};
88
89#ifdef __cpp_deduction_guides
90template <typename F> QScopeGuard(F(&)()) -> QScopeGuard<F(*)()>;
91#endif
92
93//! [qScopeGuard]
94template <typename F>
95[[nodiscard]] QScopeGuard<typename std::decay<F>::type> qScopeGuard(F &&f)
96{
97 return QScopeGuard<typename std::decay<F>::type>(std::forward<F>(f));
98}
99
100QT_END_NAMESPACE
101
102#endif // QSCOPEGUARD_H
103