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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
++ // Qt-Security score:significant reason:default
++
++ #ifndef QPROPERTY_P_H
++ #define QPROPERTY_P_H
++
++ //
++ // W A R N I N G
++ // -------------
++ //
++ // This file is not part of the Qt API. It exists for the convenience
++ // of a number of Qt sources files. This header file may change from
++ // version to version without notice, or even be removed.
++ //
++ // We mean it.
++ //
++
++ #include <private/qglobal_p.h>
++ #include <qproperty.h>
++
++ #include <qmetaobject.h>
++ #include <qscopedvaluerollback.h>
++ #include <qvariant.h>
++ #include <vector>
++ #include <QtCore/QVarLengthArray>
++
++ #include <memory>
++
++ QT_BEGIN_NAMESPACE
++
++ namespace QtPrivate {
++ Q_CORE_EXPORT bool isAnyBindingEvaluating();
++ struct QBindingStatusAccessToken {};
++
++ namespace BindableWarnings {
++ Q_CORE_EXPORT void printSignalArgumentsWithCustomGetter();
++ }
++ }
++
++
++ /*!
++ \internal
++ Similar to \c QPropertyBindingPrivatePtr, but stores a
++ \c QPropertyObserver * linking to the QPropertyBindingPrivate*
++ instead of the QPropertyBindingPrivate* itself
++ */
++ struct QBindingObserverPtr
++ {
++ private:
++ QPropertyObserver *d = nullptr;
++ public:
++ QBindingObserverPtr() = default;
++ Q_DISABLE_COPY(QBindingObserverPtr)
++ void swap(QBindingObserverPtr &other) noexcept
++ { qt_ptr_swap(d, other.d); }
++ QBindingObserverPtr(QBindingObserverPtr &&other) noexcept : d(std::exchange(other.d, nullptr)) {}
++ QT_MOVE_ASSIGNMENT_OPERATOR_IMPL_VIA_MOVE_AND_SWAP(QBindingObserverPtr)
++
++
++ inline QBindingObserverPtr(QPropertyObserver *observer) noexcept;
++ inline ~QBindingObserverPtr();
++ inline QPropertyBindingPrivate *binding() const noexcept;
++ inline QPropertyObserver *operator ->();
++ };
++
++ using PendingBindingObserverList = QVarLengthArray<QPropertyBindingPrivatePtr>;
++
++ // Keep all classes related to QProperty in one compilation unit. Performance of this code is crucial and
++ // we need to allow the compiler to inline where it makes sense.
++
++ // This is a helper "namespace"
++ struct QPropertyBindingDataPointer
++ {
++ const QtPrivate::QPropertyBindingData *ptr = nullptr;
++
++ QPropertyBindingPrivate *binding() const
++ {
++ return ptr->binding();
++ }
++
++ void setObservers(QPropertyObserver *observer)
++ {
++ auto &d = ptr->d_ref();
++ observer->prev = reinterpret_cast<QPropertyObserver**>(&d);
++ d = reinterpret_cast<quintptr>(observer);
++ }
++ static void fixupAfterMove(QtPrivate::QPropertyBindingData *ptr);
++ Q_ALWAYS_INLINE void addObserver(QPropertyObserver *observer);
++ inline void setFirstObserver(QPropertyObserver *observer);
++ inline QPropertyObserverPointer firstObserver() const;
++ static QPropertyProxyBindingData *proxyData(QtPrivate::QPropertyBindingData *ptr);
++
++ inline int observerCount() const;
++
++ template <typename T>
++ static QPropertyBindingDataPointer get(QProperty<T> &property)
++ {
++ return QPropertyBindingDataPointer{&property.bindingData()};
++ }
++ };
++
++ struct QPropertyObserverNodeProtector
++ {
++ Q_DISABLE_COPY_MOVE(QPropertyObserverNodeProtector)
++
++ QPropertyObserverBase m_placeHolder;
++ Q_NODISCARD_CTOR
++ QPropertyObserverNodeProtector(QPropertyObserver *observer)
++ {
++ // insert m_placeholder after observer into the linked list
++ QPropertyObserver *next = observer->next.data();
++ m_placeHolder.next = next;
++ observer->next = static_cast<QPropertyObserver *>(&m_placeHolder);
++ if (next)
++ next->prev = &m_placeHolder.next;
++ m_placeHolder.prev = &observer->next;
++ m_placeHolder.next.setTag(QPropertyObserver::ObserverIsPlaceholder);
++ }
++
++ QPropertyObserver *next() const { return m_placeHolder.next.data(); }
++
++ ~QPropertyObserverNodeProtector();
++ };
++
++ // This is a helper "namespace"
++ struct QPropertyObserverPointer
++ {
++ QPropertyObserver *ptr = nullptr;
++
++ void unlink()
++ {
++ unlink_common();
++ #if QT_DEPRECATED_SINCE(6, 6)
++ QT_WARNING_PUSH QT_WARNING_DISABLE_DEPRECATED
++ if (ptr->next.tag() == QPropertyObserver::ObserverIsAlias)
++ ptr->aliasData = nullptr;
++ QT_WARNING_POP
++ #endif
++ }
++
++ void unlink_fast()
++ {
++ #if QT_DEPRECATED_SINCE(6, 6)
++ QT_WARNING_PUSH QT_WARNING_DISABLE_DEPRECATED
++ Q_ASSERT(ptr->next.tag() != QPropertyObserver::ObserverIsAlias);
++ QT_WARNING_POP
++ #endif
++ unlink_common();
++ }
++
++ void setBindingToNotify(QPropertyBindingPrivate *binding)
++ {
++ Q_ASSERT(ptr->next.tag() != QPropertyObserver::ObserverIsPlaceholder);
++ ptr->binding = binding;
++ ptr->next.setTag(QPropertyObserver::ObserverNotifiesBinding);
++ }
++
++ void setBindingToNotify_unsafe(QPropertyBindingPrivate *binding);
++ void setChangeHandler(QPropertyObserver::ChangeHandler changeHandler);
++
++ enum class Notify {Everything, OnlyChangeHandlers};
++
++ void notify(QUntypedPropertyData *propertyDataPtr);
++ #ifndef QT_NO_DEBUG
++ void noSelfDependencies(QPropertyBindingPrivate *binding);
++ #else
++ void noSelfDependencies(QPropertyBindingPrivate *) {}
++ #endif
++ void evaluateBindings(PendingBindingObserverList &bindingObservers, QBindingStatus *status);
++ void observeProperty(QPropertyBindingDataPointer property);
++
++ explicit operator bool() const { return ptr != nullptr; }
++
++ QPropertyObserverPointer nextObserver() const { return {ptr->next.data()}; }
++
++ QPropertyBindingPrivate *binding() const
++ {
++ Q_ASSERT(ptr->next.tag() == QPropertyObserver::ObserverNotifiesBinding);
++ return ptr->binding;
++ }
++
++ private:
++ void unlink_common()
++ {
++ if (ptr->next)
++ ptr->next->prev = ptr->prev;
++ if (ptr->prev)
++ ptr->prev.setPointer(ptr->next.data());
++ ptr->next = nullptr;
++ ptr->prev.clear();
++ }
++ };
++
++ class QPropertyBindingErrorPrivate : public QSharedData
++ {
++ public:
++ QPropertyBindingError::Type type = QPropertyBindingError::NoError;
++ QString description;
++ };
++
++ namespace QtPrivate {
++
++ struct BindingEvaluationState
++ {
++ BindingEvaluationState(QPropertyBindingPrivate *binding, QBindingStatus *status);
++ ~BindingEvaluationState()
++ {
++ *currentState = previousState;
++ }
++
++ QPropertyBindingPrivate *binding;
++ BindingEvaluationState *previousState = nullptr;
++ BindingEvaluationState **currentState = nullptr;
++ QVarLengthArray<const QPropertyBindingData *, 8> alreadyCaptureProperties;
++ };
++
++ /*!
++ * \internal
++ * CompatPropertySafePoint needs to be constructed before the setter of
++ * a QObjectCompatProperty runs. It prevents spurious binding dependencies
++ * caused by reads of properties inside the compat property setter.
++ * Moreover, it ensures that we don't destroy bindings when using operator=
++ */
++ struct CompatPropertySafePoint
++ {
++ Q_CORE_EXPORT CompatPropertySafePoint(QBindingStatus *status, QUntypedPropertyData *property);
++ ~CompatPropertySafePoint()
++ {
++ *currentState = previousState;
++ *currentlyEvaluatingBindingList = bindingState;
++ }
++ QUntypedPropertyData *property;
++ CompatPropertySafePoint *previousState = nullptr;
++ CompatPropertySafePoint **currentState = nullptr;
++ QtPrivate::BindingEvaluationState **currentlyEvaluatingBindingList = nullptr;
++ QtPrivate::BindingEvaluationState *bindingState = nullptr;
++ };
++
++ /*!
++ * \internal
++ * While the regular QProperty notification for a compat property runs we
++ * don't want to have any currentCompatProperty set. This would be a _different_
++ * one than the one we are current evaluating. Therefore it's misleading and
++ * prevents the registering of actual dependencies.
++ */
++ struct CurrentCompatPropertyThief
++ {
++ Q_DISABLE_COPY_MOVE(CurrentCompatPropertyThief)
++ QScopedValueRollback<CompatPropertySafePoint *> m_guard;
++ public:
++ Q_NODISCARD_CTOR
++ CurrentCompatPropertyThief(QBindingStatus *status)
++ : m_guard(status->currentCompatProperty, nullptr)
++ {
++ }
++ };
++
++ }
++
++ class Q_CORE_EXPORT QPropertyBindingPrivate : public QtPrivate::RefCounted
++ {
++ private:
++ friend struct QPropertyBindingDataPointer;
++ friend class QPropertyBindingPrivatePtr;
++
++ using ObserverArray = std::array<QPropertyObserver, 4>;
++
++ private:
++
++ // used to detect binding loops for lazy evaluated properties
++ bool updating = false;
++ bool hasStaticObserver = false;
++ bool pendingNotify = false;
++ bool hasBindingWrapper:1;
++ // used to detect binding loops for eagerly evaluated properties
++ bool isQQmlPropertyBinding:1;
++ /* a sticky binding does not get removed in removeBinding
++ this is used to support QQmlPropertyData::DontRemoveBinding
++ in qtdeclarative
++ */
++ bool m_sticky:1;
++
++ const QtPrivate::BindingFunctionVTable *vtable;
++
++ union {
++ QtPrivate::QPropertyObserverCallback staticObserverCallback = nullptr;
++ QtPrivate::QPropertyBindingWrapper staticBindingWrapper;
++ };
++ ObserverArray inlineDependencyObservers; // for things we are observing
++
++ QPropertyObserverPointer firstObserver; // list of observers observing us
++ std::unique_ptr<std::vector<QPropertyObserver>> heapObservers; // for things we are observing
++
++ protected:
++ QUntypedPropertyData *propertyDataPtr = nullptr;
++
++ /* For bindings set up from C++, location stores where the binding was created in the C++ source
++ For QQmlPropertyBinding that information does not make sense, and the location in the QML file
++ is stored somewhere else. To make efficient use of the space, we instead provide a scratch space
++ for QQmlPropertyBinding (which stores further binding information there).
++ Anything stored in the union must be trivially destructible.
++ (checked in qproperty.cpp)
++
++ The discriminator for this union is the isQQmlPropertyBinding flag above. It has nothing to
++ do with custom vtables per se. Depending on what is stored in declarativeExtraData, you may
++ want vtable support for it, but since declarativeExtraData is well inside
++ QPropertyBindingPrivate it can be a regular vtable. In practice, QML bindings have custom
++ vtables because they store additional data _outside_ QPropertyBindingPrivate.
++ */
++ using DeclarativeErrorCallback = void(*)(QPropertyBindingPrivate *);
++ union {
++ QPropertyBindingSourceLocation location;
++ struct {
++ std::byte declarativeExtraData[sizeof(QPropertyBindingSourceLocation) - sizeof(DeclarativeErrorCallback)];
++ DeclarativeErrorCallback errorCallBack;
++ };
++ };
++ private:
++ QPropertyBindingError m_error;
++
++ QMetaType metaType;
++
++ public:
++ static constexpr size_t getSizeEnsuringAlignment() {
++ constexpr auto align = alignof (std::max_align_t) - 1;
++ constexpr size_t sizeEnsuringAlignment = (sizeof(QPropertyBindingPrivate) + align) & ~align;
++ static_assert (sizeEnsuringAlignment % alignof (std::max_align_t) == 0,
++ "Required for placement new'ing the function behind it.");
++ return sizeEnsuringAlignment;
++ }
++
++ const QtPrivate::BindingFunctionVTable *bindingFunctionVTable() const { return vtable; }
++
++ // public because the auto-tests access it, too.
++ size_t dependencyObserverCount = 0;
++
++ bool isUpdating() {return updating;}
++ void setSticky(bool keep = true) {m_sticky = keep;}
++ bool isSticky() {return m_sticky;}
++ void scheduleNotify() {pendingNotify = true;}
++
++ QPropertyBindingPrivate(QMetaType metaType, const QtPrivate::BindingFunctionVTable *vtable,
++ const QPropertyBindingSourceLocation &location, bool isQQmlPropertyBinding=false)
++ : hasBindingWrapper(false)
++ , isQQmlPropertyBinding(isQQmlPropertyBinding)
++ , m_sticky(false)
++ , vtable(vtable)
++ , location(location)
++ , metaType(metaType)
++ {}
++ ~QPropertyBindingPrivate();
++
++
++ void setProperty(QUntypedPropertyData *propertyPtr) { propertyDataPtr = propertyPtr; }
++ void setStaticObserver(QtPrivate::QPropertyObserverCallback callback, QtPrivate::QPropertyBindingWrapper bindingWrapper)
++ {
++ Q_ASSERT(!(callback && bindingWrapper));
++ if (callback) {
++ hasStaticObserver = true;
++ hasBindingWrapper = false;
++ staticObserverCallback = callback;
++ } else if (bindingWrapper) {
++ hasStaticObserver = false;
++ hasBindingWrapper = true;
++ staticBindingWrapper = bindingWrapper;
++ } else {
++ hasStaticObserver = false;
++ hasBindingWrapper = false;
++ staticObserverCallback = nullptr;
++ }
++ }
++ void prependObserver(QPropertyObserverPointer observer)
++ {
++ observer.ptr->prev = const_cast<QPropertyObserver **>(&firstObserver.ptr);
++ firstObserver = observer;
++ }
++
++ QPropertyObserverPointer takeObservers()
++ {
++ auto observers = firstObserver;
++ firstObserver.ptr = nullptr;
++ return observers;
++ }
++
++ void clearDependencyObservers();
++
++ Q_ALWAYS_INLINE QPropertyObserverPointer allocateDependencyObserver() {
++ if (dependencyObserverCount < inlineDependencyObservers.size()) {
++ ++dependencyObserverCount;
++ return {&inlineDependencyObservers[dependencyObserverCount - 1]};
++ }
++ return allocateDependencyObserver_slow();
++ }
++
++ QPropertyObserverPointer allocateDependencyObserver_slow();
++
++ QPropertyBindingSourceLocation sourceLocation() const
++ {
++ if (!isQQmlPropertyBinding)
++ return location;
++ return []() {
++ constexpr auto msg = "Custom location";
++ QPropertyBindingSourceLocation result;
++ result.fileName = msg;
++ return result;
++ }();
++ }
++ QPropertyBindingError bindingError() const { return m_error; }
++ QMetaType valueMetaType() const { return metaType; }
++
++ void unlinkAndDeref();
++
++ bool evaluateRecursive(PendingBindingObserverList &bindingObservers, QBindingStatus *status = nullptr);
++
++ Q_ALWAYS_INLINE bool evaluateRecursive_inline(PendingBindingObserverList &bindingObservers, QBindingStatus *status);
++
++ void notifyNonRecursive(const PendingBindingObserverList &bindingObservers);
++ enum NotificationState : bool { Delayed, Sent };
++ NotificationState notifyNonRecursive();
++
++ static QPropertyBindingPrivate *get(const QUntypedPropertyBinding &binding)
++ { return static_cast<QPropertyBindingPrivate *>(binding.d.data()); }
++ static QUntypedPropertyBinding makeUntyped(QPropertyBindingPrivate *d)
++ { return QUntypedPropertyBinding(static_cast<void *>(d)); }
++
++ void setError(QPropertyBindingError &&e)
++ { m_error = std::move(e); }
++
++ void detachFromProperty()
++ {
++ hasStaticObserver = false;
++ hasBindingWrapper = false;
++ propertyDataPtr = nullptr;
++ clearDependencyObservers();
++ }
++
++ static QPropertyBindingPrivate *currentlyEvaluatingBinding();
++
++ /* In some cases we want to run the vtable's dtor _in place_ of ~QPropertBindingPrivate() rather
++ than in addition, in order to cater to special memory layouts with extra trailing fields. The
++ vtable's size member acts as flag for this. We call this a "custom" vtable. Note that you
++ could have a QML binding with a regular vtable, as well as a non-QML binding with custom
++ vtable. In practice, QML bindings have custom vtables because they store additional data
++ after QPropertyBindingPrivate.
++ */
++ bool hasCustomVTable() const
++ {
++ return vtable->size == 0;
++ }
++
++ /* Determines whether we have a regular source location or declarativeExtraData + errorCallback.
++ * This has nothing to do with custom vtables per se.
++ */
++ bool isQmlBinding() const
++ {
++ return isQQmlPropertyBinding;
++ }
++
++ static void destroyAndFreeMemory(QPropertyBindingPrivate *priv) {
++ if (priv->hasCustomVTable()) {
++ // special hack for QQmlPropertyBinding which has a
++ // different memory layout than normal QPropertyBindings
++ priv->vtable->destroy(priv);
++ } else{
++ priv->~QPropertyBindingPrivate();
++ delete[] reinterpret_cast<std::byte *>(priv);
++ }
++ }
++ };
++
++ inline void QPropertyBindingDataPointer::setFirstObserver(QPropertyObserver *observer)
++ {
++ if (auto *b = binding()) {
++ b->firstObserver.ptr = observer;
++ return;
++ }
++ auto &d = ptr->d_ref();
++ d = reinterpret_cast<quintptr>(observer);
++ }
++
++ inline void QPropertyBindingDataPointer::fixupAfterMove(QtPrivate::QPropertyBindingData *ptr)
++ {
++ auto &d = ptr->d_ref();
++ if (ptr->isNotificationDelayed()) {
++ QPropertyProxyBindingData *proxy = ptr->proxyData();
++ Q_ASSERT(proxy);
++ proxy->originalBindingData = ptr;
++ }
++ // If QPropertyBindingData has been moved, and it has an observer
++ // we have to adjust the firstObserver's prev pointer to point to
++ // the moved to QPropertyBindingData's d_ptr
++ if (d & QtPrivate::QPropertyBindingData::BindingBit)
++ return; // nothing to do if the observer is stored in the binding
++ if (auto observer = reinterpret_cast<QPropertyObserver *>(d))
++ observer->prev = reinterpret_cast<QPropertyObserver **>(&d);
++ }
++
++ inline QPropertyObserverPointer QPropertyBindingDataPointer::firstObserver() const
++ {
++ if (auto *b = binding())
++ return b->firstObserver;
++ return { reinterpret_cast<QPropertyObserver *>(ptr->d()) };
++ }
++
++ /*!
++ \internal
++ Returns the proxy data of \a ptr, or \c nullptr if \a ptr has no delayed notification
++ */
++ inline QPropertyProxyBindingData *QPropertyBindingDataPointer::proxyData(QtPrivate::QPropertyBindingData *ptr)
++ {
++ if (!ptr->isNotificationDelayed())
++ return nullptr;
++ return ptr->proxyData();
++ }
++
++ inline int QPropertyBindingDataPointer::observerCount() const
++ {
++ int count = 0;
++ for (auto observer = firstObserver(); observer; observer = observer.nextObserver())
++ ++count;
++ return count;
++ }
++
++ namespace QtPrivate {
++ Q_CORE_EXPORT bool isPropertyInBindingWrapper(const QUntypedPropertyData *property);
++ void Q_CORE_EXPORT initBindingStatusThreadId();
++ }
++
++ template<typename Class, typename T, auto Offset, auto Setter, auto Signal = nullptr,
++ auto Getter = nullptr>
++ class QObjectCompatProperty : public QPropertyData<T>
++ {
++ template<typename Property, typename>
++ friend class QtPrivate::QBindableInterfaceForProperty;
++
++ using ThisType = QObjectCompatProperty<Class, T, Offset, Setter, Signal, Getter>;
++ using SignalTakesValue = std::is_invocable<decltype(Signal), Class, T>;
++ Class *owner()
++ {
++ char *that = reinterpret_cast<char *>(this);
++ return reinterpret_cast<Class *>(that - QtPrivate::detail::getOffset(Offset));
++ }
++ const Class *owner() const
++ {
++ char *that = const_cast<char *>(reinterpret_cast<const char *>(this));
++ return reinterpret_cast<Class *>(that - QtPrivate::detail::getOffset(Offset));
++ }
++
++ static bool bindingWrapper(QMetaType type, QUntypedPropertyData *dataPtr, QtPrivate::QPropertyBindingFunction binding)
++ {
++ auto *thisData = static_cast<ThisType *>(dataPtr);
++ QBindingStorage *storage = qGetBindingStorage(thisData->owner());
++ QPropertyData<T> copy(thisData->valueBypassingBindings());
++ {
++ QtPrivate::CurrentCompatPropertyThief thief(storage->bindingStatus);
++ if (!binding.vtable->call(type, ©, binding.functor))
++ return false;
++ }
++ // ensure value and setValue know we're currently evaluating our binding
++ QtPrivate::CompatPropertySafePoint guardThis(storage->bindingStatus, thisData);
++ (thisData->owner()->*Setter)(copy.valueBypassingBindings());
++ return true;
++ }
++ bool inBindingWrapper(const QBindingStorage *storage) const
++ {
++ return storage->bindingStatus && storage->bindingStatus->currentCompatProperty
++ && QtPrivate::isPropertyInBindingWrapper(this);
++ }
++
++ inline static T getPropertyValue(const QUntypedPropertyData *d) {
++ auto prop = static_cast<const ThisType *>(d);
++ if constexpr (std::is_null_pointer_v<decltype(Getter)>)
++ return prop->value();
++ else
++ return (prop->owner()->*Getter)();
++ }
++
++ inline static T getPropertyValueBypassingBindings(const QUntypedPropertyData *d) {
++ auto prop = static_cast<const ThisType *>(d);
++ if constexpr (std::is_null_pointer_v<decltype(Getter)>)
++ return prop->valueBypassingBindings();
++ else
++ return (prop->owner()->*Getter)();
++ }
++
++ inline static void warnIfSignalWithArgumentAndCustomGetter()
++ {
++ if constexpr (!std::is_null_pointer_v<decltype(Signal)>
++ && SignalTakesValue::value
++ && !std::is_null_pointer_v<decltype(Getter)>) {
++ QtPrivate::BindableWarnings::printSignalArgumentsWithCustomGetter();
++ }
++ }
++
++ public:
++ using value_type = typename QPropertyData<T>::value_type;
++ using parameter_type = typename QPropertyData<T>::parameter_type;
++ using arrow_operator_result = typename QPropertyData<T>::arrow_operator_result;
++
++ QObjectCompatProperty() { warnIfSignalWithArgumentAndCustomGetter(); }
++ explicit QObjectCompatProperty(const T &initialValue) : QPropertyData<T>(initialValue)
++ {
++ warnIfSignalWithArgumentAndCustomGetter();
++ }
++ explicit QObjectCompatProperty(T &&initialValue) : QPropertyData<T>(std::move(initialValue))
++ {
++ warnIfSignalWithArgumentAndCustomGetter();
++ }
++
++ parameter_type value() const
++ {
++ const QBindingStorage *storage = qGetBindingStorage(owner());
++ // make sure we don't register this binding as a dependency to itself
++ if (storage->bindingStatus && storage->bindingStatus->currentlyEvaluatingBinding && !inBindingWrapper(storage))
++ storage->registerDependency_helper(this);
++ return this->val;
++ }
++
++ arrow_operator_result operator->() const
++ {
++ if constexpr (QTypeTraits::is_dereferenceable_v<T>) {
++ return value();
++ } else if constexpr (std::is_pointer_v<T>) {
++ value();
++ return this->val;
++ } else {
++ return;
++ }
++ }
++
++ parameter_type operator*() const
++ {
++ return value();
++ }
++
++ operator parameter_type() const
++ {
++ return value();
++ }
++
++ void setValue(parameter_type t)
++ {
++ QBindingStorage *storage = qGetBindingStorage(owner());
++ if (auto *bd = storage->bindingData(this)) {
++ // make sure we don't remove the binding if called from the bindingWrapper
++ if (bd->hasBinding() && !inBindingWrapper(storage))
++ bd->removeBinding_helper();
++ }
++ this->val = t;
++ }
++
++ QObjectCompatProperty &operator=(parameter_type newValue)
++ {
++ setValue(newValue);
++ return *this;
++ }
++
++ QPropertyBinding<T> setBinding(const QPropertyBinding<T> &newBinding)
++ {
++ QtPrivate::QPropertyBindingData *bd = qGetBindingStorage(owner())->bindingData(this, true);
++ QUntypedPropertyBinding oldBinding(bd->setBinding(newBinding, this, nullptr, bindingWrapper));
++ // notification is already handled in QPropertyBindingData::setBinding
++ return static_cast<QPropertyBinding<T> &>(oldBinding);
++ }
++
++ bool setBinding(const QUntypedPropertyBinding &newBinding)
++ {
++ if (!newBinding.isNull() && newBinding.valueMetaType() != QMetaType::fromType<T>())
++ return false;
++ setBinding(static_cast<const QPropertyBinding<T> &>(newBinding));
++ return true;
++ }
++
++ #ifndef Q_QDOC
++ template <typename Functor>
++ QPropertyBinding<T> setBinding(Functor &&f,
++ const QPropertyBindingSourceLocation &location = QT_PROPERTY_DEFAULT_BINDING_LOCATION,
++ std::enable_if_t<std::is_invocable_v<Functor>> * = nullptr)
++ {
++ return setBinding(Qt::makePropertyBinding(std::forward<Functor>(f), location));
++ }
++ #else
++ template <typename Functor>
++ QPropertyBinding<T> setBinding(Functor f);
++ #endif
++
++ bool hasBinding() const {
++ auto *bd = qGetBindingStorage(owner())->bindingData(this);
++ return bd && bd->binding() != nullptr;
++ }
++
++ void removeBindingUnlessInWrapper()
++ {
++ QBindingStorage *storage = qGetBindingStorage(owner());
++ if (auto *bd = storage->bindingData(this)) {
++ // make sure we don't remove the binding if called from the bindingWrapper
++ if (bd->hasBinding() && !inBindingWrapper(storage))
++ bd->removeBinding_helper();
++ }
++ }
++
++ void notify()
++ {
++ QBindingStorage *storage = qGetBindingStorage(owner());
++ if (auto bd = storage->bindingData(this, false)) {
++ // This partly duplicates QPropertyBindingData::notifyObservers because we want to
++ // check for inBindingWrapper() after checking for isNotificationDelayed() and
++ // firstObserver. This is because inBindingWrapper() is the most expensive check.
++ if (!bd->isNotificationDelayed()) {
++ QPropertyBindingDataPointer d{bd};
++ if (QPropertyObserverPointer observer = d.firstObserver()) {
++ if (!inBindingWrapper(storage)) {
++ PendingBindingObserverList bindingObservers;
++ if (bd->notifyObserver_helper(this, storage, observer, bindingObservers)
++ == QtPrivate::QPropertyBindingData::Evaluated) {
++ // evaluateBindings() can trash the observers.
++ // It can also reallocate binding data pointer.
++ // So, we need to re-fetch here.
++ bd = storage->bindingData(this, false);
++ QPropertyBindingDataPointer dd{bd};
++ if (QPropertyObserverPointer obs = dd.firstObserver())
++ obs.notify(this);
++ for (auto&& bindingPtr: bindingObservers) {
++ auto *binding = static_cast<QPropertyBindingPrivate *>(bindingPtr.get());
++ binding->notifyNonRecursive();
++ }
++ }
++ }
++ }
++ }
++ }
++ if constexpr (!std::is_null_pointer_v<decltype(Signal)>) {
++ if constexpr (SignalTakesValue::value)
++ (owner()->*Signal)(getPropertyValueBypassingBindings(this));
++ else
++ (owner()->*Signal)();
++ }
++ }
++
++ QPropertyBinding<T> binding() const
++ {
++ auto *bd = qGetBindingStorage(owner())->bindingData(this);
++ QUntypedPropertyBinding binding = QPropertyBindingPrivate::makeUntyped(bd ? bd->binding() : nullptr);
++ return static_cast<QPropertyBinding<T> &&>(binding);
++ }
++
++ QPropertyBinding<T> takeBinding()
++ {
++ return setBinding(QPropertyBinding<T>());
++ }
++
++ template<typename Functor>
++ [[nodiscard]]
++ QPropertyChangeHandler<Functor> onValueChanged(Functor f)
++ {
++ static_assert(std::is_invocable_v<Functor>, "Functor callback must be callable without any parameters");
++ return QPropertyChangeHandler<Functor>(*this, f);
++ }
++
++ template<typename Functor>
++ [[nodiscard]]
++ QPropertyChangeHandler<Functor> subscribe(Functor f)
++ {
++ static_assert(std::is_invocable_v<Functor>, "Functor callback must be callable without any parameters");
++ f();
++ return onValueChanged(f);
++ }
++
++ template<typename Functor>
++ [[nodiscard]]
++ QPropertyNotifier addNotifier(Functor f)
++ {
++ static_assert(std::is_invocable_v<Functor>, "Functor callback must be callable without any parameters");
++ return QPropertyNotifier(*this, f);
++ }
++
++ QtPrivate::QPropertyBindingData &bindingData() const
++ {
++ auto *storage = const_cast<QBindingStorage *>(qGetBindingStorage(owner()));
++ return *storage->bindingData(const_cast<QObjectCompatProperty *>(this), true);
++ }
++ };
++
++ namespace QtPrivate {
++ template<typename Class, typename Ty, auto Offset, auto Setter, auto Signal, auto Getter>
++ class QBindableInterfaceForProperty<
++ QObjectCompatProperty<Class, Ty, Offset, Setter, Signal, Getter>, std::void_t<Class>>
++ {
++ using Property = QObjectCompatProperty<Class, Ty, Offset, Setter, Signal, Getter>;
++ using T = typename Property::value_type;
++ public:
++ static constexpr QBindableInterface iface = {
++ [](const QUntypedPropertyData *d, void *value) -> void
++ { *static_cast<T*>(value) = Property::getPropertyValue(d); },
++ [](QUntypedPropertyData *d, const void *value) -> void
++ {
++ (static_cast<Property *>(d)->owner()->*Setter)(*static_cast<const T*>(value));
++ },
++ [](const QUntypedPropertyData *d) -> QUntypedPropertyBinding
++ { return static_cast<const Property *>(d)->binding(); },
++ [](QUntypedPropertyData *d, const QUntypedPropertyBinding &binding) -> QUntypedPropertyBinding
++ { return static_cast<Property *>(d)->setBinding(static_cast<const QPropertyBinding<T> &>(binding)); },
++ [](const QUntypedPropertyData *d, const QPropertyBindingSourceLocation &location) -> QUntypedPropertyBinding
++ { return Qt::makePropertyBinding([d]() -> T { return Property::getPropertyValue(d); }, location); },
++ [](const QUntypedPropertyData *d, QPropertyObserver *observer) -> void
++ { observer->setSource(static_cast<const Property *>(d)->bindingData()); },
++ []() { return QMetaType::fromType<T>(); }
++ };
++ };
++ }
++
++ #define QT_OBJECT_COMPAT_PROPERTY_4(Class, Type, name, setter) \
++ static constexpr size_t _qt_property_##name##_offset() { \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ return offsetof(Class, name); \
++ QT_WARNING_POP \
++ } \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter> name;
++
++ #define QT_OBJECT_COMPAT_PROPERTY_5(Class, Type, name, setter, signal) \
++ static constexpr size_t _qt_property_##name##_offset() { \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ return offsetof(Class, name); \
++ QT_WARNING_POP \
++ } \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter, signal> name;
++
++ #define Q_OBJECT_COMPAT_PROPERTY(...) \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ QT_OVERLOADED_MACRO(QT_OBJECT_COMPAT_PROPERTY, __VA_ARGS__) \
++ QT_WARNING_POP
++
++ #define QT_OBJECT_COMPAT_PROPERTY_WITH_ARGS_5(Class, Type, name, setter, value) \
++ static constexpr size_t _qt_property_##name##_offset() { \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ return offsetof(Class, name); \
++ QT_WARNING_POP \
++ } \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter> name = \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter>( \
++ value);
++
++ #define QT_OBJECT_COMPAT_PROPERTY_WITH_ARGS_6(Class, Type, name, setter, signal, value) \
++ static constexpr size_t _qt_property_##name##_offset() { \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ return offsetof(Class, name); \
++ QT_WARNING_POP \
++ } \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter, signal> name = \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter, \
++ signal>(value);
++
++ #define QT_OBJECT_COMPAT_PROPERTY_WITH_ARGS_7(Class, Type, name, setter, signal, getter, value) \
++ static constexpr size_t _qt_property_##name##_offset() { \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ return offsetof(Class, name); \
++ QT_WARNING_POP \
++ } \
++ QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter, signal, getter>\
++ name = QObjectCompatProperty<Class, Type, Class::_qt_property_##name##_offset, setter, \
++ signal, getter>(value);
++
++ #define Q_OBJECT_COMPAT_PROPERTY_WITH_ARGS(...) \
++ QT_WARNING_PUSH QT_WARNING_DISABLE_INVALID_OFFSETOF \
++ QT_OVERLOADED_MACRO(QT_OBJECT_COMPAT_PROPERTY_WITH_ARGS, __VA_ARGS__) \
++ QT_WARNING_POP
++
++
++ namespace QtPrivate {
++ Q_CORE_EXPORT BindingEvaluationState *suspendCurrentBindingStatus();
++ Q_CORE_EXPORT void restoreBindingStatus(BindingEvaluationState *status);
++ }
++
++ struct QUntypedBindablePrivate
++ {
++ static QtPrivate::QBindableInterface const *getInterface(const QUntypedBindable &bindable)
++ {
++ return bindable.iface;
++ }
++
++ static QUntypedPropertyData *getPropertyData(const QUntypedBindable &bindable)
++ {
++ return bindable.data;
++ }
++ };
++
++ inline bool QPropertyBindingPrivate::evaluateRecursive_inline(PendingBindingObserverList &bindingObservers, QBindingStatus *status)
++ {
++ if (updating) {
++ m_error = QPropertyBindingError(QPropertyBindingError::BindingLoop);
++ if (isQQmlPropertyBinding)
++ errorCallBack(this);
++ return false;
++ }
++
++ /*
++ * Evaluating the binding might lead to the binding being broken. This can
++ * cause ref to reach zero at the end of the function. However, the
++ * updateGuard's destructor will then still trigger, trying to set the
++ * updating bool to its old value
++ * To prevent this, we create a QPropertyBindingPrivatePtr which ensures
++ * that the object is still alive when updateGuard's dtor runs.
++ */
++ QPropertyBindingPrivatePtr keepAlive {this};
++
++ QScopedValueRollback<bool> updateGuard(updating, true);
++
++ QtPrivate::BindingEvaluationState evaluationFrame(this, status);
++
++ auto bindingFunctor = reinterpret_cast<std::byte *>(this) +
++ QPropertyBindingPrivate::getSizeEnsuringAlignment();
++ bool changed = false;
++ if (hasBindingWrapper) {
++ changed = staticBindingWrapper(metaType, propertyDataPtr,
++ {vtable, bindingFunctor});
++ } else {
++ changed = vtable->call(metaType, propertyDataPtr, bindingFunctor);
++ }
++ // If there was a change, we must set pendingNotify.
++ // If there was not, we must not clear it, as that only should happen in notifyRecursive
++ pendingNotify = pendingNotify || changed;
++ if (!changed || !firstObserver)
++ return changed;
++
++ firstObserver.noSelfDependencies(this);
++ firstObserver.evaluateBindings(bindingObservers, status);
++ return true;
++ }
++
++ /*!
++ \internal
++
++ Walks through the list of property observers, and calls any ChangeHandler
++ found there.
++ It doesn't do anything with bindings, which are only handled in
++ QPropertyBindingPrivate::evaluateRecursive.
++ */
++ inline void QPropertyObserverPointer::notify(QUntypedPropertyData *propertyDataPtr)
++ {
++ auto observer = const_cast<QPropertyObserver*>(ptr);
++ /*
++ * The basic idea of the loop is as follows: We iterate over all observers in the linked list,
++ * and execute the functionality corresponding to their tag.
++ * However, complication arise due to the fact that the triggered operations might modify the list,
++ * which includes deletion and move of the current and next nodes.
++ * Therefore, we take a few safety precautions:
++ * 1. Before executing any action which might modify the list, we insert a placeholder node after the current node.
++ * As that one is stack allocated and owned by us, we can rest assured that it is
++ * still there after the action has executed, and placeHolder->next points to the actual next node in the list.
++ * Note that taking next at the beginning of the loop does not work, as the executed action might either move
++ * or delete that node.
++ * 2. After the triggered action has finished, we can use the next pointer in the placeholder node as a safe way to
++ * retrieve the next node.
++ * 3. Some care needs to be taken to avoid infinite recursion with change handlers, so we add an extra test there, that
++ * checks whether we're already have the same change handler in our call stack. This can be done by checking whether
++ * the node after the current one is a placeholder node.
++ */
++ while (observer) {
++ QPropertyObserver *next = observer->next.data();
++ switch (QPropertyObserver::ObserverTag(observer->next.tag())) {
++ case QPropertyObserver::ObserverNotifiesChangeHandler:
++ {
++ auto handlerToCall = observer->changeHandler;
++ // prevent recursion
++ if (next && next->next.tag() == QPropertyObserver::ObserverIsPlaceholder) {
++ observer = next->next.data();
++ continue;
++ }
++ // handlerToCall might modify the list
++ QPropertyObserverNodeProtector protector(observer);
++ handlerToCall(observer, propertyDataPtr);
++ next = protector.next();
++ break;
++ }
++ case QPropertyObserver::ObserverNotifiesBinding:
++ break;
++ case QPropertyObserver::ObserverIsPlaceholder:
++ // recursion is already properly handled somewhere else
++ break;
++ #if QT_DEPRECATED_SINCE(6, 6)
++ QT_WARNING_PUSH QT_WARNING_DISABLE_DEPRECATED
++ case QPropertyObserver::ObserverIsAlias:
++ break;
++ QT_WARNING_POP
++ #endif
++ default: Q_UNREACHABLE();
++ }
++ observer = next;
++ }
++ }
++
++ inline QPropertyObserverNodeProtector::~QPropertyObserverNodeProtector()
++ {
++ QPropertyObserverPointer d{static_cast<QPropertyObserver *>(&m_placeHolder)};
++ d.unlink_fast();
++ }
++
++ QBindingObserverPtr::QBindingObserverPtr(QPropertyObserver *observer) noexcept : d(observer)
++ {
++ Q_ASSERT(d);
++ QPropertyObserverPointer{d}.binding()->addRef();
++ }
++
++ QBindingObserverPtr::~QBindingObserverPtr()
++ {
++ if (!d)
++ return;
++
++ QPropertyBindingPrivate *bindingPrivate = binding();
++ if (!bindingPrivate->deref())
++ QPropertyBindingPrivate::destroyAndFreeMemory(bindingPrivate);
++ }
++
++ QPropertyBindingPrivate *QBindingObserverPtr::binding() const noexcept { return QPropertyObserverPointer{d}.binding(); }
++
++ QPropertyObserver *QBindingObserverPtr::operator->() { return d; }
++
++ namespace QtPrivate {
++ class QPropertyAdaptorSlotObject : public QUntypedPropertyData, public QSlotObjectBase
++ {
++ QPropertyBindingData bindingData_;
++ QObject *obj;
++ QMetaProperty metaProperty_;
++
++ #if QT_VERSION < QT_VERSION_CHECK(7, 0, 0)
++ static void impl(int which, QSlotObjectBase *this_, QObject *r, void **a, bool *ret);
++ #else
++ static void impl(QSlotObjectBase *this_, QObject *r, void **a, int which, bool *ret);
++ #endif
++
++ QPropertyAdaptorSlotObject(QObject *o, const QMetaProperty& p);
++
++ public:
++ static QPropertyAdaptorSlotObject *cast(QSlotObjectBase *ptr, int propertyIndex)
++ {
++ if (ptr->isImpl(&QPropertyAdaptorSlotObject::impl)) {
++ auto p = static_cast<QPropertyAdaptorSlotObject *>(ptr);
++ if (p->metaProperty_.propertyIndex() == propertyIndex)
++ return p;
++ }
++ return nullptr;
++ }
++
++ inline const QPropertyBindingData &bindingData() const { return bindingData_; }
++ inline QPropertyBindingData &bindingData() { return bindingData_; }
++ inline QObject *object() const { return obj; }
++ inline const QMetaProperty &metaProperty() const { return metaProperty_; }
++
++ friend class QT_PREPEND_NAMESPACE(QUntypedBindable);
++ };
++ }
++
++ QT_END_NAMESPACE
++
++ #endif // QPROPERTY_P_H