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+// Copyright (C) 2022 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QTCLASSHELPERMACROS_H
+#define QTCLASSHELPERMACROS_H
+
+#include <QtCore/qtconfigmacros.h>
+
+#if 0
+#pragma qt_class(QtClassHelperMacros)
+#pragma qt_sync_stop_processing
+#endif
+
+QT_BEGIN_NAMESPACE
+
+#if defined(__cplusplus)
+
+/*
+ Some classes do not permit copies to be made of an object. These
+ classes contains a private copy constructor and assignment
+ operator to disable copying (the compiler gives an error message).
+*/
+#define Q_DISABLE_COPY(Class) \
+ Class(const Class &) = delete;\
+ Class &operator=(const Class &) = delete;
+
+#define Q_DISABLE_COPY_MOVE(Class) \
+ Q_DISABLE_COPY(Class) \
+ Class(Class &&) = delete; \
+ Class &operator=(Class &&) = delete;
+
+/*
+ Implementing a move assignment operator using an established
+ technique (move-and-swap, pure swap) is just boilerplate.
+ Here's a couple of *private* macros for convenience.
+
+ To know which one to use:
+
+ * if you don't have a move constructor (*) => use pure swap;
+ * if you have a move constructor, then
+ * if your class holds just memory (no file handles, no user-defined
+ datatypes, etc.) => use pure swap;
+ * use move and swap.
+
+ The preference should always go for the move-and-swap one, as it
+ will deterministically destroy the data previously held in *this,
+ and not "dump" it in the moved-from object (which may then be alive
+ for longer).
+
+ The requirement for either macro is the presence of a member swap(),
+ which any value class that defines its own special member functions
+ should have anyhow.
+
+ (*) Many value classes in Qt do not have move constructors; mostly,
+ the implicitly shared classes using QSharedDataPointer and friends.
+ The reason is mostly historical: those classes require either an
+ out-of-line move constructor, which we could not provide before we
+ made C++11 mandatory (and that we don't like anyhow), or
+ an out-of-line dtor for the Q(E)DSP<Private> member (cf. QPixmap).
+
+ If you can however add a move constructor to a class lacking it,
+ consider doing so, then reevaluate which macro to choose.
+*/
+#define QT_MOVE_ASSIGNMENT_OPERATOR_IMPL_VIA_MOVE_AND_SWAP(Class) \
+ Class &operator=(Class &&other) noexcept { \
+ Class moved(std::move(other)); \
+ swap(moved); \
+ return *this; \
+ }
+
+#define QT_MOVE_ASSIGNMENT_OPERATOR_IMPL_VIA_PURE_SWAP(Class) \
+ Class &operator=(Class &&other) noexcept { \
+ swap(other); \
+ return *this; \
+ }
+
+template <typename T> inline T *qGetPtrHelper(T *ptr) noexcept { return ptr; }
+template <typename Ptr> inline auto qGetPtrHelper(Ptr &ptr) noexcept -> decltype(ptr.get())
+{ static_assert(noexcept(ptr.get()), "Smart d pointers for Q_DECLARE_PRIVATE must have noexcept get()"); return ptr.get(); }
+
+class QObject;
+class QObjectPrivate;
+namespace QtPrivate {
+ template <typename ObjPrivate> void assertObjectType(QObjectPrivate *d);
+ inline const QObject *getQObject(const QObjectPrivate *d);
+}
+
+#define Q_DECLARE_PRIVATE(Class) \
+ inline Class##Private* d_func() noexcept \
+ { Q_CAST_IGNORE_ALIGN(return reinterpret_cast<Class##Private *>(qGetPtrHelper(d_ptr));) } \
+ inline const Class##Private* d_func() const noexcept \
+ { Q_CAST_IGNORE_ALIGN(return reinterpret_cast<const Class##Private *>(qGetPtrHelper(d_ptr));) } \
+ friend class Class##Private;
+
+#define Q_DECLARE_PRIVATE_D(Dptr, Class) \
+ inline Class##Private* d_func() noexcept \
+ { Q_CAST_IGNORE_ALIGN(return reinterpret_cast<Class##Private *>(qGetPtrHelper(Dptr));) } \
+ inline const Class##Private* d_func() const noexcept \
+ { Q_CAST_IGNORE_ALIGN(return reinterpret_cast<const Class##Private *>(qGetPtrHelper(Dptr));) } \
+ friend class Class##Private;
+
+#define Q_DECLARE_PUBLIC(Class) \
+ inline Class* q_func() noexcept { return static_cast<Class *>(q_ptr); } \
+ inline const Class* q_func() const noexcept { return static_cast<const Class *>(q_ptr); } \
+ friend class Class; \
+ friend const QObject *QtPrivate::getQObject(const QObjectPrivate *d); \
+ template <typename ObjPrivate> friend void QtPrivate::assertObjectType(QObjectPrivate *d);
+
+#define Q_D(Class) Class##Private * const d = d_func()
+#define Q_Q(Class) Class * const q = q_func()
+
+/*
+ Specialize a shared type with:
+
+ Q_DECLARE_SHARED(type)
+
+ where 'type' is the name of the type to specialize. NOTE: shared
+ types must define a member-swap, and be defined in the same
+ namespace as Qt for this to work.
+*/
+
+#define Q_DECLARE_SHARED(TYPE) \
+Q_DECLARE_TYPEINFO(TYPE, Q_RELOCATABLE_TYPE); \
+inline void swap(TYPE &value1, TYPE &value2) \
+ noexcept(noexcept(value1.swap(value2))) \
+{ value1.swap(value2); }
+
+#endif // __cplusplus
+
+QT_END_NAMESPACE
+
+#endif // QTCLASSHELPERMACROS_H