diff options
Diffstat (limited to 'src/corelib/kernel/qobject.cpp')
| -rw-r--r-- | src/corelib/kernel/qobject.cpp | 1271 |
1 files changed, 700 insertions, 571 deletions
diff --git a/src/corelib/kernel/qobject.cpp b/src/corelib/kernel/qobject.cpp index 598ce75bd4..cf107498dd 100644 --- a/src/corelib/kernel/qobject.cpp +++ b/src/corelib/kernel/qobject.cpp @@ -1,6 +1,6 @@ /**************************************************************************** ** -** Copyright (C) 2016 The Qt Company Ltd. +** Copyright (C) 2019 The Qt Company Ltd. ** Copyright (C) 2016 Intel Corporation. ** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com> ** Contact: https://www.qt.io/licensing/ @@ -58,6 +58,7 @@ #include <qdebug.h> #include <qpair.h> #include <qvarlengtharray.h> +#include <qscopeguard.h> #include <qset.h> #if QT_CONFIG(thread) #include <qsemaphore.h> @@ -77,6 +78,12 @@ QT_BEGIN_NAMESPACE static int DIRECT_CONNECTION_ONLY = 0; +Q_CORE_EXPORT QBasicAtomicPointer<QSignalSpyCallbackSet> qt_signal_spy_callback_set = Q_BASIC_ATOMIC_INITIALIZER(nullptr); + +void qt_register_signal_spy_callbacks(QSignalSpyCallbackSet *callback_set) +{ + qt_signal_spy_callback_set.storeRelease(callback_set); +} QDynamicMetaObjectData::~QDynamicMetaObjectData() { @@ -86,12 +93,6 @@ QAbstractDynamicMetaObject::~QAbstractDynamicMetaObject() { } - -struct QSlotObjectBaseDeleter { // for use with QScopedPointer<QSlotObjectBase,...> - static void cleanup(QtPrivate::QSlotObjectBase *slot) { - if (slot) slot->destroyIfLastRef(); - } -}; static int *queuedConnectionTypes(const QList<QByteArray> &typeNames) { int *types = new int [typeNames.count() + 1]; @@ -146,10 +147,9 @@ static QBasicMutex _q_ObjectMutexPool[131]; * \internal * mutex to be locked when accessing the connectionlists or the senders list */ -static inline QMutex *signalSlotLock(const QObject *o) +static inline QBasicMutex *signalSlotLock(const QObject *o) { - return static_cast<QMutex *>(&_q_ObjectMutexPool[ - uint(quintptr(o)) % sizeof(_q_ObjectMutexPool)/sizeof(QBasicMutex)]); + return &_q_ObjectMutexPool[uint(quintptr(o)) % sizeof(_q_ObjectMutexPool)/sizeof(QBasicMutex)]; } #if QT_VERSION < 0x60000 @@ -160,39 +160,6 @@ extern "C" Q_CORE_EXPORT void qt_removeObject(QObject *) {} #endif -struct QConnectionSenderSwitcher { - QObject *receiver; - QObjectPrivate::Sender *previousSender; - QObjectPrivate::Sender currentSender; - bool switched; - - inline QConnectionSenderSwitcher() : switched(false) {} - - inline QConnectionSenderSwitcher(QObject *receiver, QObject *sender, int signal_absolute_id) - { - switchSender(receiver, sender, signal_absolute_id); - } - - inline void switchSender(QObject *receiver, QObject *sender, int signal_absolute_id) - { - this->receiver = receiver; - currentSender.sender = sender; - currentSender.signal = signal_absolute_id; - currentSender.ref = 1; - previousSender = QObjectPrivate::setCurrentSender(receiver, ¤tSender); - switched = true; - } - - inline ~QConnectionSenderSwitcher() - { - if (switched) - QObjectPrivate::resetCurrentSender(receiver, ¤tSender, previousSender); - } -private: - Q_DISABLE_COPY(QConnectionSenderSwitcher) -}; - - void (*QAbstractDeclarativeData::destroyed)(QAbstractDeclarativeData *, QObject *) = 0; void (*QAbstractDeclarativeData::destroyed_qml1)(QAbstractDeclarativeData *, QObject *) = 0; void (*QAbstractDeclarativeData::parentChanged)(QAbstractDeclarativeData *, QObject *, QObject *) = 0; @@ -201,6 +168,12 @@ int (*QAbstractDeclarativeData::receivers)(QAbstractDeclarativeData *, const QO bool (*QAbstractDeclarativeData::isSignalConnected)(QAbstractDeclarativeData *, const QObject *, int) = 0; void (*QAbstractDeclarativeData::setWidgetParent)(QObject *, QObject *) = 0; +/*! + \fn QObjectData::QObjectData() + \internal + */ + + QObjectData::~QObjectData() {} QMetaObject *QObjectData::dynamicMetaObject() const @@ -209,7 +182,7 @@ QMetaObject *QObjectData::dynamicMetaObject() const } QObjectPrivate::QObjectPrivate(int version) - : threadData(0), connectionLists(0), senders(0), currentSender(0), currentChildBeingDeleted(0) + : threadData(0), currentChildBeingDeleted(0) { #ifdef QT_BUILD_INTERNAL // Don't check the version parameter in internal builds. @@ -232,7 +205,6 @@ QObjectPrivate::QObjectPrivate(int version) receiveChildEvents = true; postedEvents = 0; extraData = 0; - connectedSignals[0] = connectedSignals[1] = 0; metaObject = 0; isWindow = false; deleteLaterCalled = false; @@ -241,10 +213,10 @@ QObjectPrivate::QObjectPrivate(int version) QObjectPrivate::~QObjectPrivate() { if (extraData && !extraData->runningTimers.isEmpty()) { - if (Q_LIKELY(threadData->thread == QThread::currentThread())) { + if (Q_LIKELY(threadData->thread.loadAcquire() == QThread::currentThread())) { // unregister pending timers if (threadData->hasEventDispatcher()) - threadData->eventDispatcher.load()->unregisterTimers(q_ptr); + threadData->eventDispatcher.loadRelaxed()->unregisterTimers(q_ptr); // release the timer ids back to the pool for (int i = 0; i < extraData->runningTimers.size(); ++i) @@ -285,59 +257,22 @@ static void computeOffsets(const QMetaObject *metaobject, int *signalOffset, int } } -/* - This vector contains the all connections from an object. - - Each object may have one vector containing the lists of - connections for a given signal. The index in the vector correspond - to the signal index. The signal index is the one returned by - QObjectPrivate::signalIndex (not QMetaObject::indexOfSignal). - Negative index means connections to all signals. - - This vector is protected by the object mutex (signalSlotMutexes()) - - Each Connection is also part of a 'senders' linked list. The mutex - of the receiver must be locked when touching the pointers of this - linked list. -*/ -class QObjectConnectionListVector : public QVector<QObjectPrivate::ConnectionList> -{ -public: - bool orphaned; //the QObject owner of this vector has been destroyed while the vector was inUse - bool dirty; //some Connection have been disconnected (their receiver is 0) but not removed from the list yet - int inUse; //number of functions that are currently accessing this object or its connections - QObjectPrivate::ConnectionList allsignals; - - QObjectConnectionListVector() - : QVector<QObjectPrivate::ConnectionList>(), orphaned(false), dirty(false), inUse(0) - { } - - QObjectPrivate::ConnectionList &operator[](int at) - { - if (at < 0) - return allsignals; - return QVector<QObjectPrivate::ConnectionList>::operator[](at); - } -}; - // Used by QAccessibleWidget bool QObjectPrivate::isSender(const QObject *receiver, const char *signal) const { Q_Q(const QObject); int signal_index = signalIndex(signal); - if (signal_index < 0) + ConnectionData *cd = connections.loadRelaxed(); + if (signal_index < 0 || !cd) return false; - QMutexLocker locker(signalSlotLock(q)); - if (connectionLists) { - if (signal_index < connectionLists->count()) { - const QObjectPrivate::Connection *c = - connectionLists->at(signal_index).first; - - while (c) { - if (c->receiver == receiver) - return true; - c = c->nextConnectionList; - } + QBasicMutexLocker locker(signalSlotLock(q)); + if (signal_index < cd->signalVectorCount()) { + const QObjectPrivate::Connection *c = cd->signalVector.loadRelaxed()->at(signal_index).first.loadRelaxed(); + + while (c) { + if (c->receiver.loadRelaxed() == receiver) + return true; + c = c->nextConnectionList.loadRelaxed(); } } return false; @@ -346,21 +281,19 @@ bool QObjectPrivate::isSender(const QObject *receiver, const char *signal) const // Used by QAccessibleWidget QObjectList QObjectPrivate::receiverList(const char *signal) const { - Q_Q(const QObject); QObjectList returnValue; int signal_index = signalIndex(signal); - if (signal_index < 0) + ConnectionData *cd = connections.loadRelaxed(); + if (signal_index < 0 || !cd) return returnValue; - QMutexLocker locker(signalSlotLock(q)); - if (connectionLists) { - if (signal_index < connectionLists->count()) { - const QObjectPrivate::Connection *c = connectionLists->at(signal_index).first; - - while (c) { - if (c->receiver) - returnValue << c->receiver; - c = c->nextConnectionList; - } + if (signal_index < cd->signalVectorCount()) { + const QObjectPrivate::Connection *c = cd->signalVector.loadRelaxed()->at(signal_index).first.loadRelaxed(); + + while (c) { + QObject *r = c->receiver.loadRelaxed(); + if (r) + returnValue << r; + c = c->nextConnectionList.loadRelaxed(); } } return returnValue; @@ -370,9 +303,12 @@ QObjectList QObjectPrivate::receiverList(const char *signal) const QObjectList QObjectPrivate::senderList() const { QObjectList returnValue; - QMutexLocker locker(signalSlotLock(q_func())); - for (Connection *c = senders; c; c = c->next) - returnValue << c->sender; + ConnectionData *cd = connections.loadRelaxed(); + if (cd) { + QBasicMutexLocker locker(signalSlotLock(q_func())); + for (Connection *c = cd->senders; c; c = c->next) + returnValue << c->sender; + } return returnValue; } @@ -389,103 +325,271 @@ QObjectList QObjectPrivate::senderList() const void QObjectPrivate::addConnection(int signal, Connection *c) { Q_ASSERT(c->sender == q_ptr); - if (!connectionLists) - connectionLists = new QObjectConnectionListVector(); - if (signal >= connectionLists->count()) - connectionLists->resize(signal + 1); - - ConnectionList &connectionList = (*connectionLists)[signal]; - if (connectionList.last) { - connectionList.last->nextConnectionList = c; + ensureConnectionData(); + ConnectionData *cd = connections.loadRelaxed(); + cd->resizeSignalVector(signal + 1); + + ConnectionList &connectionList = cd->connectionsForSignal(signal); + if (connectionList.last.loadRelaxed()) { + Q_ASSERT(connectionList.last.loadRelaxed()->receiver.loadRelaxed()); + connectionList.last.loadRelaxed()->nextConnectionList.storeRelaxed(c); } else { - connectionList.first = c; + connectionList.first.storeRelaxed(c); } - connectionList.last = c; + c->id = ++cd->currentConnectionId; + c->prevConnectionList = connectionList.last.loadRelaxed(); + connectionList.last.storeRelaxed(c); - cleanConnectionLists(); + QObjectPrivate *rd = QObjectPrivate::get(c->receiver.loadRelaxed()); + rd->ensureConnectionData(); - c->prev = &(QObjectPrivate::get(c->receiver)->senders); + c->prev = &(rd->connections.loadRelaxed()->senders); c->next = *c->prev; *c->prev = c; if (c->next) c->next->prev = &c->next; +} + +void QObjectPrivate::ConnectionData::removeConnection(QObjectPrivate::Connection *c) +{ + Q_ASSERT(c->receiver.loadRelaxed()); + ConnectionList &connections = signalVector.loadRelaxed()->at(c->signal_index); + c->receiver.storeRelaxed(nullptr); + QThreadData *td = c->receiverThreadData.loadRelaxed(); + if (td) + td->deref(); + c->receiverThreadData.storeRelaxed(nullptr); - if (signal < 0) { - connectedSignals[0] = connectedSignals[1] = ~0; - } else if (signal < (int)sizeof(connectedSignals) * 8) { - connectedSignals[signal >> 5] |= (1 << (signal & 0x1f)); +#ifndef QT_NO_DEBUG + bool found = false; + for (Connection *cc = connections.first.loadRelaxed(); cc; cc = cc->nextConnectionList.loadRelaxed()) { + if (cc == c) { + found = true; + break; + } + } + Q_ASSERT(found); +#endif + + // remove from the senders linked list + *c->prev = c->next; + if (c->next) + c->next->prev = c->prev; + c->prev = nullptr; + + if (connections.first.loadRelaxed() == c) + connections.first.storeRelaxed(c->nextConnectionList.loadRelaxed()); + if (connections.last.loadRelaxed() == c) + connections.last.storeRelaxed(c->prevConnectionList); + Q_ASSERT(signalVector.loadRelaxed()->at(c->signal_index).first.loadRelaxed() != c); + Q_ASSERT(signalVector.loadRelaxed()->at(c->signal_index).last.loadRelaxed() != c); + + // keep c->nextConnectionList intact, as it might still get accessed by activate + Connection *n = c->nextConnectionList.loadRelaxed(); + if (n) + n->prevConnectionList = c->prevConnectionList; + if (c->prevConnectionList) + c->prevConnectionList->nextConnectionList.storeRelaxed(n); + c->prevConnectionList = nullptr; + + Q_ASSERT(c != orphaned.loadRelaxed()); + // add c to orphanedConnections + c->nextInOrphanList = orphaned.loadRelaxed(); + orphaned.storeRelaxed(c); + +#ifndef QT_NO_DEBUG + found = false; + for (Connection *cc = connections.first.loadRelaxed(); cc; cc = cc->nextConnectionList.loadRelaxed()) { + if (cc == c) { + found = true; + break; + } } + Q_ASSERT(!found); +#endif + } -void QObjectPrivate::cleanConnectionLists() +void QObjectPrivate::ConnectionData::cleanOrphanedConnectionsImpl(QObject *sender) { - if (connectionLists->dirty && !connectionLists->inUse) { - // remove broken connections - bool allConnected = false; - for (int signal = -1; signal < connectionLists->count(); ++signal) { - QObjectPrivate::ConnectionList &connectionList = - (*connectionLists)[signal]; - - // Set to the last entry in the connection list that was *not* - // deleted. This is needed to update the list's last pointer - // at the end of the cleanup. - QObjectPrivate::Connection *last = 0; - - QObjectPrivate::Connection **prev = &connectionList.first; - QObjectPrivate::Connection *c = *prev; - bool connected = false; // whether the signal is still connected somewhere - while (c) { - if (c->receiver) { - last = c; - prev = &c->nextConnectionList; - c = *prev; - connected = true; - } else { - QObjectPrivate::Connection *next = c->nextConnectionList; - *prev = next; - c->deref(); - c = next; - } - } + ConnectionOrSignalVector *c = nullptr; + { + QBasicMutexLocker l(signalSlotLock(sender)); + if (ref.loadAcquire() > 1) + return; + + // Since ref == 1, no activate() is in process since we locked the mutex. That implies, + // that nothing can reference the orphaned connection objects anymore and they can + // be safely deleted + c = orphaned.loadRelaxed(); + orphaned.storeRelaxed(nullptr); + } + deleteOrphaned(c); +} - // Correct the connection list's last pointer. - // As conectionList.last could equal last, this could be a noop - connectionList.last = last; +void QObjectPrivate::ConnectionData::deleteOrphaned(QObjectPrivate::ConnectionOrSignalVector *o) +{ + while (o) { + QObjectPrivate::ConnectionOrSignalVector *next = nullptr; + if (SignalVector *v = ConnectionOrSignalVector::asSignalVector(o)) { + next = v->nextInOrphanList; + free(v); + } else { + QObjectPrivate::Connection *c = static_cast<Connection *>(o); + next = c->nextInOrphanList; + Q_ASSERT(!c->receiver.loadRelaxed()); + Q_ASSERT(!c->prev); + c->freeSlotObject(); + c->deref(); + } + o = next; + } +} - if (!allConnected && !connected && signal >= 0 - && size_t(signal) < sizeof(connectedSignals) * 8) { - // This signal is no longer connected - connectedSignals[signal >> 5] &= ~(1 << (signal & 0x1f)); - } else if (signal == -1) { - allConnected = connected; - } +/*! \internal + + Returns \c true if the signal with index \a signal_index from object \a sender is connected. + + \a signal_index must be the index returned by QObjectPrivate::signalIndex; +*/ +bool QObjectPrivate::isSignalConnected(uint signalIndex, bool checkDeclarative) const +{ + if (checkDeclarative && isDeclarativeSignalConnected(signalIndex)) + return true; + + ConnectionData *cd = connections.loadRelaxed(); + if (!cd) + return false; + SignalVector *signalVector = cd->signalVector.loadRelaxed(); + if (!signalVector) + return false; + + if (signalVector->at(-1).first.loadRelaxed()) + return true; + + if (signalIndex < uint(cd->signalVectorCount())) { + const QObjectPrivate::Connection *c = signalVector->at(signalIndex).first.loadRelaxed(); + while (c) { + if (c->receiver.loadRelaxed()) + return true; + c = c->nextConnectionList.loadRelaxed(); } - connectionLists->dirty = false; } + return false; +} + +bool QObjectPrivate::maybeSignalConnected(uint signalIndex) const +{ + ConnectionData *cd = connections.loadRelaxed(); + if (!cd) + return false; + SignalVector *signalVector = cd->signalVector.loadRelaxed(); + if (!signalVector) + return false; + + if (signalVector->at(-1).first.loadAcquire()) + return true; + + if (signalIndex < uint(cd->signalVectorCount())) { + const QObjectPrivate::Connection *c = signalVector->at(signalIndex).first.loadAcquire(); + return c != nullptr; + } + return false; +} + +/*! + \internal + */ +QAbstractMetaCallEvent::~QAbstractMetaCallEvent() +{ +#if QT_CONFIG(thread) + if (semaphore_) + semaphore_->release(); +#endif } /*! \internal */ -QMetaCallEvent::QMetaCallEvent(ushort method_offset, ushort method_relative, QObjectPrivate::StaticMetaCallFunction callFunction, +inline void QMetaCallEvent::allocArgs() +{ + if (!d.nargs_) + return; + + constexpr size_t each = sizeof(void*) + sizeof(int); + void *const memory = d.nargs_ * each > sizeof(prealloc_) ? + calloc(d.nargs_, each) : prealloc_; + + Q_CHECK_PTR(memory); + d.args_ = static_cast<void **>(memory); +} + +/*! + \internal + + Used for blocking queued connections, just passes \a args through without + allocating any memory. + */ +QMetaCallEvent::QMetaCallEvent(ushort method_offset, ushort method_relative, + QObjectPrivate::StaticMetaCallFunction callFunction, const QObject *sender, int signalId, - int nargs, int *types, void **args, QSemaphore *semaphore) - : QEvent(MetaCall), slotObj_(0), sender_(sender), signalId_(signalId), - nargs_(nargs), types_(types), args_(args), semaphore_(semaphore), - callFunction_(callFunction), method_offset_(method_offset), method_relative_(method_relative) -{ } + void **args, QSemaphore *semaphore) + : QAbstractMetaCallEvent(sender, signalId, semaphore), + d({nullptr, args, callFunction, 0, method_offset, method_relative}), + prealloc_() +{ +} + +/*! + \internal + + Used for blocking queued connections, just passes \a args through without + allocating any memory. + */ +QMetaCallEvent::QMetaCallEvent(QtPrivate::QSlotObjectBase *slotO, + const QObject *sender, int signalId, + void **args, QSemaphore *semaphore) + : QAbstractMetaCallEvent(sender, signalId, semaphore), + d({slotO, args, nullptr, 0, 0, ushort(-1)}), + prealloc_() +{ + if (d.slotObj_) + d.slotObj_->ref(); +} /*! \internal + + Allocates memory for \a nargs; code creating an event needs to initialize + the void* and int arrays by accessing \a args() and \a types(), respectively. */ -QMetaCallEvent::QMetaCallEvent(QtPrivate::QSlotObjectBase *slotO, const QObject *sender, int signalId, - int nargs, int *types, void **args, QSemaphore *semaphore) - : QEvent(MetaCall), slotObj_(slotO), sender_(sender), signalId_(signalId), - nargs_(nargs), types_(types), args_(args), semaphore_(semaphore), - callFunction_(0), method_offset_(0), method_relative_(ushort(-1)) +QMetaCallEvent::QMetaCallEvent(ushort method_offset, ushort method_relative, + QObjectPrivate::StaticMetaCallFunction callFunction, + const QObject *sender, int signalId, + int nargs) + : QAbstractMetaCallEvent(sender, signalId), + d({nullptr, nullptr, callFunction, nargs, method_offset, method_relative}), + prealloc_() +{ + allocArgs(); +} + +/*! + \internal + + Allocates memory for \a nargs; code creating an event needs to initialize + the void* and int arrays by accessing \a args() and \a types(), respectively. + */ +QMetaCallEvent::QMetaCallEvent(QtPrivate::QSlotObjectBase *slotO, + const QObject *sender, int signalId, + int nargs) + : QAbstractMetaCallEvent(sender, signalId), + d({slotO, nullptr, nullptr, nargs, 0, ushort(-1)}), + prealloc_() { - if (slotObj_) - slotObj_->ref(); + if (d.slotObj_) + d.slotObj_->ref(); + allocArgs(); } /*! @@ -493,20 +597,17 @@ QMetaCallEvent::QMetaCallEvent(QtPrivate::QSlotObjectBase *slotO, const QObject */ QMetaCallEvent::~QMetaCallEvent() { - if (types_) { - for (int i = 0; i < nargs_; ++i) { - if (types_[i] && args_[i]) - QMetaType::destroy(types_[i], args_[i]); + if (d.nargs_) { + int *typeIDs = types(); + for (int i = 0; i < d.nargs_; ++i) { + if (typeIDs[i] && d.args_[i]) + QMetaType::destroy(typeIDs[i], d.args_[i]); } - free(types_); - free(args_); + if (reinterpret_cast<void*>(d.args_) != reinterpret_cast<void*>(prealloc_)) + free(d.args_); } -#if QT_CONFIG(thread) - if (semaphore_) - semaphore_->release(); -#endif - if (slotObj_) - slotObj_->destroyIfLastRef(); + if (d.slotObj_) + d.slotObj_->destroyIfLastRef(); } /*! @@ -514,12 +615,13 @@ QMetaCallEvent::~QMetaCallEvent() */ void QMetaCallEvent::placeMetaCall(QObject *object) { - if (slotObj_) { - slotObj_->call(object, args_); - } else if (callFunction_ && method_offset_ <= object->metaObject()->methodOffset()) { - callFunction_(object, QMetaObject::InvokeMetaMethod, method_relative_, args_); + if (d.slotObj_) { + d.slotObj_->call(object, d.args_); + } else if (d.callFunction_ && d.method_offset_ <= object->metaObject()->methodOffset()) { + d.callFunction_(object, QMetaObject::InvokeMetaMethod, d.method_relative_, d.args_); } else { - QMetaObject::metacall(object, QMetaObject::InvokeMetaMethod, method_offset_ + method_relative_, args_); + QMetaObject::metacall(object, QMetaObject::InvokeMetaMethod, + d.method_offset_ + d.method_relative_, d.args_); } } @@ -773,8 +875,8 @@ static bool check_parent_thread(QObject *parent, QThreadData *currentThreadData) { if (parent && parentThreadData != currentThreadData) { - QThread *parentThread = parentThreadData->thread; - QThread *currentThread = currentThreadData->thread; + QThread *parentThread = parentThreadData->thread.loadAcquire(); + QThread *currentThread = currentThreadData->thread.loadAcquire(); qWarning("QObject: Cannot create children for a parent that is in a different thread.\n" "(Parent is %s(%p), parent's thread is %s(%p), current thread is %s(%p)", parent->metaObject()->className(), @@ -806,6 +908,8 @@ static bool check_parent_thread(QObject *parent, QObject::QObject(QObject *parent) : d_ptr(new QObjectPrivate) { + Q_ASSERT_X(this != parent, Q_FUNC_INFO, "Cannot parent a QObject to itself"); + Q_D(QObject); d_ptr->q_ptr = this; d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current(); @@ -834,6 +938,8 @@ QObject::QObject(QObject *parent) QObject::QObject(QObjectPrivate &dd, QObject *parent) : d_ptr(&dd) { + Q_ASSERT_X(this != parent, Q_FUNC_INFO, "Cannot parent a QObject to itself"); + Q_D(QObject); d_ptr->q_ptr = this; d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current(); @@ -894,15 +1000,15 @@ QObject::~QObject() d->wasDeleted = true; d->blockSig = 0; // unblock signals so we always emit destroyed() - QtSharedPointer::ExternalRefCountData *sharedRefcount = d->sharedRefcount.load(); + QtSharedPointer::ExternalRefCountData *sharedRefcount = d->sharedRefcount.loadRelaxed(); if (sharedRefcount) { - if (sharedRefcount->strongref.load() > 0) { + if (sharedRefcount->strongref.loadRelaxed() > 0) { qWarning("QObject: shared QObject was deleted directly. The program is malformed and may crash."); // but continue deleting, it's too late to stop anyway } // indicate to all QWeakPointers that this QObject has now been deleted - sharedRefcount->strongref.store(0); + sharedRefcount->strongref.storeRelaxed(0); if (!sharedRefcount->weakref.deref()) delete sharedRefcount; } @@ -921,92 +1027,56 @@ QObject::~QObject() } } - // set ref to zero to indicate that this object has been deleted - if (d->currentSender != 0) - d->currentSender->ref = 0; - d->currentSender = 0; + QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed(); + if (cd) { + if (cd->currentSender) { + cd->currentSender->receiverDeleted(); + cd->currentSender = nullptr; + } - if (d->connectionLists || d->senders) { - QMutex *signalSlotMutex = signalSlotLock(this); - QMutexLocker locker(signalSlotMutex); + QBasicMutex *signalSlotMutex = signalSlotLock(this); + QBasicMutexLocker locker(signalSlotMutex); // disconnect all receivers - if (d->connectionLists) { - ++d->connectionLists->inUse; - int connectionListsCount = d->connectionLists->count(); - for (int signal = -1; signal < connectionListsCount; ++signal) { - QObjectPrivate::ConnectionList &connectionList = - (*d->connectionLists)[signal]; - - while (QObjectPrivate::Connection *c = connectionList.first) { - if (!c->receiver) { - connectionList.first = c->nextConnectionList; - c->deref(); - continue; - } - - QMutex *m = signalSlotLock(c->receiver); - bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); - - if (c->receiver) { - *c->prev = c->next; - if (c->next) c->next->prev = c->prev; - } - c->receiver = 0; - if (needToUnlock) - m->unlock(); - - connectionList.first = c->nextConnectionList; - - // The destroy operation must happen outside the lock - if (c->isSlotObject) { - c->isSlotObject = false; - locker.unlock(); - c->slotObj->destroyIfLastRef(); - locker.relock(); - } - c->deref(); + int receiverCount = cd->signalVectorCount(); + for (int signal = -1; signal < receiverCount; ++signal) { + QObjectPrivate::ConnectionList &connectionList = cd->connectionsForSignal(signal); + + while (QObjectPrivate::Connection *c = connectionList.first.loadRelaxed()) { + Q_ASSERT(c->receiver.loadAcquire()); + + QBasicMutex *m = signalSlotLock(c->receiver.loadRelaxed()); + bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); + if (c->receiver.loadAcquire()) { + cd->removeConnection(c); + Q_ASSERT(connectionList.first.loadRelaxed() != c); } + if (needToUnlock) + m->unlock(); } - - if (!--d->connectionLists->inUse) { - delete d->connectionLists; - } else { - d->connectionLists->orphaned = true; - } - d->connectionLists = 0; } /* Disconnect all senders: - * This loop basically just does - * for (node = d->senders; node; node = node->next) { ... } - * - * We need to temporarily unlock the receiver mutex to destroy the functors or to lock the - * sender's mutex. And when the mutex is released, node->next might be destroyed by another - * thread. That's why we set node->prev to &node, that way, if node is destroyed, node will - * be updated. */ - QObjectPrivate::Connection *node = d->senders; - while (node) { + while (QObjectPrivate::Connection *node = cd->senders) { + Q_ASSERT(node->receiver.loadAcquire()); QObject *sender = node->sender; // Send disconnectNotify before removing the connection from sender's connection list. // This ensures any eventual destructor of sender will block on getting receiver's lock // and not finish until we release it. sender->disconnectNotify(QMetaObjectPrivate::signal(sender->metaObject(), node->signal_index)); - QMutex *m = signalSlotLock(sender); - node->prev = &node; + QBasicMutex *m = signalSlotLock(sender); bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m); //the node has maybe been removed while the mutex was unlocked in relock? - if (!node || node->sender != sender) { + if (node != cd->senders) { // We hold the wrong mutex Q_ASSERT(needToUnlock); m->unlock(); continue; } - node->receiver = 0; - QObjectConnectionListVector *senderLists = sender->d_func()->connectionLists; - if (senderLists) - senderLists->dirty = true; + + QObjectPrivate::ConnectionData *senderData = sender->d_func()->connections.loadRelaxed(); + Q_ASSERT(senderData); QtPrivate::QSlotObjectBase *slotObj = nullptr; if (node->isSlotObject) { @@ -1014,19 +1084,24 @@ QObject::~QObject() node->isSlotObject = false; } - node = node->next; + senderData->removeConnection(node); if (needToUnlock) m->unlock(); if (slotObj) { - if (node) - node->prev = &node; locker.unlock(); slotObj->destroyIfLastRef(); locker.relock(); } } + + // invalidate all connections on the object and make sure + // activate() will skip them + cd->currentConnectionId.storeRelaxed(0); } + if (cd && !cd->ref.deref()) + delete cd; + d->connections.storeRelaxed(nullptr); if (!d->children.isEmpty()) d->deleteChildren(); @@ -1046,7 +1121,7 @@ QObject::~QObject() QObjectPrivate::Connection::~Connection() { if (ownArgumentTypes) { - const int *v = argumentTypes.load(); + const int *v = argumentTypes.loadRelaxed(); if (v != &DIRECT_CONNECTION_ONLY) delete [] v; } @@ -1253,9 +1328,13 @@ bool QObject::event(QEvent *e) case QEvent::MetaCall: { - QMetaCallEvent *mce = static_cast<QMetaCallEvent*>(e); + QAbstractMetaCallEvent *mce = static_cast<QAbstractMetaCallEvent*>(e); - QConnectionSenderSwitcher sw(this, const_cast<QObject*>(mce->sender()), mce->signalId()); + if (!d_func()->connections.loadRelaxed()) { + QBasicMutexLocker locker(signalSlotLock(this)); + d_func()->ensureConnectionData(); + } + QObjectPrivate::Sender sender(this, const_cast<QObject*>(mce->sender()), mce->signalId()); mce->placeMetaCall(this); break; @@ -1264,7 +1343,7 @@ bool QObject::event(QEvent *e) case QEvent::ThreadChange: { Q_D(QObject); QThreadData *threadData = d->threadData; - QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher.load(); + QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher.loadRelaxed(); if (eventDispatcher) { QList<QAbstractEventDispatcher::TimerInfo> timers = eventDispatcher->registeredTimers(this); if (!timers.isEmpty()) { @@ -1415,7 +1494,7 @@ bool QObject::eventFilter(QObject * /* watched */, QEvent * /* event */) \sa signalsBlocked(), QSignalBlocker */ -bool QObject::blockSignals(bool block) Q_DECL_NOTHROW +bool QObject::blockSignals(bool block) noexcept { Q_D(QObject); bool previous = d->blockSig; @@ -1430,7 +1509,7 @@ bool QObject::blockSignals(bool block) Q_DECL_NOTHROW */ QThread *QObject::thread() const { - return d_func()->threadData->thread; + return d_func()->threadData->thread.loadAcquire(); } /*! @@ -1477,7 +1556,7 @@ void QObject::moveToThread(QThread *targetThread) { Q_D(QObject); - if (d->threadData->thread == targetThread) { + if (d->threadData->thread.loadAcquire() == targetThread) { // object is already in this thread return; } @@ -1493,13 +1572,13 @@ void QObject::moveToThread(QThread *targetThread) QThreadData *currentData = QThreadData::current(); QThreadData *targetData = targetThread ? QThreadData::get2(targetThread) : nullptr; - if (d->threadData->thread == 0 && currentData == targetData) { + if (d->threadData->thread.loadAcquire() == 0 && currentData == targetData) { // one exception to the rule: we allow moving objects with no thread affinity to the current thread currentData = d->threadData; } else if (d->threadData != currentData) { qWarning("QObject::moveToThread: Current thread (%p) is not the object's thread (%p).\n" "Cannot move to target thread (%p)\n", - currentData->thread.load(), d->threadData->thread.load(), targetData ? targetData->thread.load() : nullptr); + currentData->thread.loadRelaxed(), d->threadData->thread.loadRelaxed(), targetData ? targetData->thread.loadRelaxed() : nullptr); #ifdef Q_OS_MAC qWarning("You might be loading two sets of Qt binaries into the same process. " @@ -1516,6 +1595,9 @@ void QObject::moveToThread(QThread *targetThread) if (!targetData) targetData = new QThreadData(0); + // make sure nobody adds/removes connections to this object while we're moving it + QMutexLocker l(signalSlotLock(this)); + QOrderedMutexLocker locker(¤tData->postEventList.mutex, &targetData->postEventList.mutex); @@ -1561,13 +1643,35 @@ void QObjectPrivate::setThreadData_helper(QThreadData *currentData, QThreadData } if (eventsMoved > 0 && targetData->hasEventDispatcher()) { targetData->canWait = false; - targetData->eventDispatcher.load()->wakeUp(); + targetData->eventDispatcher.loadRelaxed()->wakeUp(); } // the current emitting thread shouldn't restore currentSender after calling moveToThread() - if (currentSender) - currentSender->ref = 0; - currentSender = 0; + ConnectionData *cd = connections.loadRelaxed(); + if (cd) { + if (cd->currentSender) { + cd->currentSender->receiverDeleted(); + cd->currentSender = nullptr; + } + + // adjust the receiverThreadId values in the Connections + if (cd) { + auto *c = cd->senders; + while (c) { + QObject *r = c->receiver.loadRelaxed(); + if (r) { + Q_ASSERT(r == q); + targetData->ref(); + QThreadData *old = c->receiverThreadData.loadRelaxed(); + if (old) + old->deref(); + c->receiverThreadData.storeRelaxed(targetData); + } + c = c->next; + } + } + + } // set new thread data targetData->ref(); @@ -1584,7 +1688,7 @@ void QObjectPrivate::_q_reregisterTimers(void *pointer) { Q_Q(QObject); QList<QAbstractEventDispatcher::TimerInfo> *timerList = reinterpret_cast<QList<QAbstractEventDispatcher::TimerInfo> *>(pointer); - QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher.load(); + QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher.loadRelaxed(); for (int i = 0; i < timerList->size(); ++i) { const QAbstractEventDispatcher::TimerInfo &ti = timerList->at(i); eventDispatcher->registerTimer(ti.timerId, ti.interval, ti.timerType, q); @@ -1650,7 +1754,7 @@ int QObject::startTimer(int interval, Qt::TimerType timerType) qWarning("QObject::startTimer: Timers cannot be started from another thread"); return 0; } - int timerId = d->threadData->eventDispatcher.load()->registerTimer(interval, timerType, this); + int timerId = d->threadData->eventDispatcher.loadRelaxed()->registerTimer(interval, timerType, this); if (!d->extraData) d->extraData = new QObjectPrivate::ExtraData; d->extraData->runningTimers.append(timerId); @@ -1716,16 +1820,16 @@ void QObject::killTimer(int id) int at = d->extraData ? d->extraData->runningTimers.indexOf(id) : -1; if (at == -1) { // timer isn't owned by this object - qWarning("QObject::killTimer(): Error: timer id %d is not valid for object %p (%s, %s), timer has not been killed", + qWarning("QObject::killTimer(): Error: timer id %d is not valid for object %p (%s, %ls), timer has not been killed", id, this, metaObject()->className(), - qPrintable(objectName())); + qUtf16Printable(objectName())); return; } if (d->threadData->hasEventDispatcher()) - d->threadData->eventDispatcher.load()->unregisterTimer(id); + d->threadData->eventDispatcher.loadRelaxed()->unregisterTimer(id); d->extraData->runningTimers.remove(at); QAbstractEventDispatcherPrivate::releaseTimerId(id); @@ -2026,8 +2130,25 @@ void QObjectPrivate::deleteChildren() void QObjectPrivate::setParent_helper(QObject *o) { Q_Q(QObject); + Q_ASSERT_X(q != o, Q_FUNC_INFO, "Cannot parent a QObject to itself"); +#ifdef QT_DEBUG + const auto checkForParentChildLoops = qScopeGuard([&](){ + int depth = 0; + auto p = parent; + while (p) { + if (++depth == CheckForParentChildLoopsWarnDepth) { + qWarning("QObject %p (class: '%s', object name: '%s') may have a loop in its parent-child chain; " + "this is undefined behavior", + q, q->metaObject()->className(), qPrintable(q->objectName())); + } + p = p->parent(); + } + }); +#endif + if (o == parent) return; + if (parent) { QObjectPrivate *parentD = parent->d_func(); if (parentD->isDeletingChildren && wasDeleted @@ -2378,13 +2499,14 @@ QObject *QObject::sender() const { Q_D(const QObject); - QMutexLocker locker(signalSlotLock(this)); - if (!d->currentSender) - return 0; + QBasicMutexLocker locker(signalSlotLock(this)); + QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed(); + if (!cd || !cd->currentSender) + return nullptr; - for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) { - if (c->sender == d->currentSender->sender) - return d->currentSender->sender; + for (QObjectPrivate::Connection *c = cd->senders; c; c = c->next) { + if (c->sender == cd->currentSender->sender) + return cd->currentSender->sender; } return 0; @@ -2419,14 +2541,15 @@ int QObject::senderSignalIndex() const { Q_D(const QObject); - QMutexLocker locker(signalSlotLock(this)); - if (!d->currentSender) + QBasicMutexLocker locker(signalSlotLock(this)); + QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed(); + if (!cd || !cd->currentSender) return -1; - for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) { - if (c->sender == d->currentSender->sender) { + for (QObjectPrivate::Connection *c = cd->senders; c; c = c->next) { + if (c->sender == cd->currentSender->sender) { // Convert from signal range to method range - return QMetaObjectPrivate::signal(c->sender->metaObject(), d->currentSender->signal).methodIndex(); + return QMetaObjectPrivate::signal(c->sender->metaObject(), cd->currentSender->signal).methodIndex(); } } @@ -2482,15 +2605,13 @@ int QObject::receivers(const char *signal) const signal_index); } - QMutexLocker locker(signalSlotLock(this)); - if (d->connectionLists) { - if (signal_index < d->connectionLists->count()) { - const QObjectPrivate::Connection *c = - d->connectionLists->at(signal_index).first; - while (c) { - receivers += c->receiver ? 1 : 0; - c = c->nextConnectionList; - } + QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed(); + QBasicMutexLocker locker(signalSlotLock(this)); + if (cd && signal_index < cd->signalVectorCount()) { + const QObjectPrivate::Connection *c = cd->signalVector.loadRelaxed()->at(signal_index).first.loadRelaxed(); + while (c) { + receivers += c->receiver.loadRelaxed() ? 1 : 0; + c = c->nextConnectionList.loadRelaxed(); } } } @@ -2530,22 +2651,8 @@ bool QObject::isSignalConnected(const QMetaMethod &signal) const signalIndex += QMetaObjectPrivate::signalOffset(signal.mobj); - QMutexLocker locker(signalSlotLock(this)); - if (d->connectionLists) { - if (signalIndex < sizeof(d->connectedSignals) * 8 && !d->connectionLists->dirty) - return d->isSignalConnected(signalIndex); - - if (signalIndex < uint(d->connectionLists->count())) { - const QObjectPrivate::Connection *c = - d->connectionLists->at(signalIndex).first; - while (c) { - if (c->receiver) - return true; - c = c->nextConnectionList; - } - } - } - return d->isDeclarativeSignalConnected(signalIndex); + QBasicMutexLocker locker(signalSlotLock(this)); + return d->isSignalConnected(signalIndex, true); } /*! @@ -3308,49 +3415,49 @@ QObjectPrivate::Connection *QMetaObjectPrivate::connect(const QObject *sender, int method_offset = rmeta ? rmeta->methodOffset() : 0; Q_ASSERT(!rmeta || QMetaObjectPrivate::get(rmeta)->revision >= 6); - QObjectPrivate::StaticMetaCallFunction callFunction = - rmeta ? rmeta->d.static_metacall : 0; + QObjectPrivate::StaticMetaCallFunction callFunction = rmeta ? rmeta->d.static_metacall : nullptr; QOrderedMutexLocker locker(signalSlotLock(sender), signalSlotLock(receiver)); - if (type & Qt::UniqueConnection) { - QObjectConnectionListVector *connectionLists = QObjectPrivate::get(s)->connectionLists; - if (connectionLists && connectionLists->count() > signal_index) { - const QObjectPrivate::Connection *c2 = - (*connectionLists)[signal_index].first; + QObjectPrivate::ConnectionData *scd = QObjectPrivate::get(s)->connections.loadRelaxed(); + if (type & Qt::UniqueConnection && scd) { + if (scd->signalVectorCount() > signal_index) { + const QObjectPrivate::Connection *c2 = scd->signalVector.loadRelaxed()->at(signal_index).first.loadRelaxed(); int method_index_absolute = method_index + method_offset; while (c2) { - if (!c2->isSlotObject && c2->receiver == receiver && c2->method() == method_index_absolute) - return 0; - c2 = c2->nextConnectionList; + if (!c2->isSlotObject && c2->receiver.loadRelaxed() == receiver && c2->method() == method_index_absolute) + return nullptr; + c2 = c2->nextConnectionList.loadRelaxed(); } } type &= Qt::UniqueConnection - 1; } - QScopedPointer<QObjectPrivate::Connection> c(new QObjectPrivate::Connection); + std::unique_ptr<QObjectPrivate::Connection> c{new QObjectPrivate::Connection}; c->sender = s; c->signal_index = signal_index; - c->receiver = r; + c->receiver.storeRelaxed(r); + QThreadData *td = r->d_func()->threadData; + td->ref(); + c->receiverThreadData.storeRelaxed(td); c->method_relative = method_index; c->method_offset = method_offset; c->connectionType = type; c->isSlotObject = false; - c->argumentTypes.store(types); - c->nextConnectionList = 0; + c->argumentTypes.storeRelaxed(types); c->callFunction = callFunction; - QObjectPrivate::get(s)->addConnection(signal_index, c.data()); + QObjectPrivate::get(s)->addConnection(signal_index, c.get()); locker.unlock(); QMetaMethod smethod = QMetaObjectPrivate::signal(smeta, signal_index); if (smethod.isValid()) s->connectNotify(smethod); - return c.take(); + return c.release(); } /*! @@ -3386,47 +3493,38 @@ bool QMetaObject::disconnectOne(const QObject *sender, int signal_index, \internal Helper function to remove the connection from the senders list and set the receivers to \nullptr */ -bool QMetaObjectPrivate::disconnectHelper(QObjectPrivate::Connection *c, +bool QMetaObjectPrivate::disconnectHelper(QObjectPrivate::ConnectionData *connections, int signalIndex, const QObject *receiver, int method_index, void **slot, - QMutex *senderMutex, DisconnectType disconnectType) + QBasicMutex *senderMutex, DisconnectType disconnectType) { bool success = false; + + auto &connectionList = connections->connectionsForSignal(signalIndex); + auto *c = connectionList.first.loadRelaxed(); while (c) { - if (c->receiver - && (receiver == 0 || (c->receiver == receiver + QObject *r = c->receiver.loadRelaxed(); + if (r && (receiver == nullptr || (r == receiver && (method_index < 0 || (!c->isSlotObject && c->method() == method_index)) - && (slot == 0 || (c->isSlotObject && c->slotObj->compare(slot)))))) { + && (slot == nullptr || (c->isSlotObject && c->slotObj->compare(slot)))))) { bool needToUnlock = false; - QMutex *receiverMutex = 0; - if (c->receiver) { - receiverMutex = signalSlotLock(c->receiver); + QBasicMutex *receiverMutex = nullptr; + if (r) { + receiverMutex = signalSlotLock(r); // need to relock this receiver and sender in the correct order needToUnlock = QOrderedMutexLocker::relock(senderMutex, receiverMutex); } - if (c->receiver) { - *c->prev = c->next; - if (c->next) - c->next->prev = c->prev; - } + if (c->receiver.loadRelaxed()) + connections->removeConnection(c); if (needToUnlock) receiverMutex->unlock(); - c->receiver = 0; - - if (c->isSlotObject) { - c->isSlotObject = false; - senderMutex->unlock(); - c->slotObj->destroyIfLastRef(); - senderMutex->lock(); - } - success = true; if (disconnectType == DisconnectOne) return success; } - c = c->nextConnectionList; + c = c->nextConnectionList.loadRelaxed(); } return success; } @@ -3445,43 +3543,34 @@ bool QMetaObjectPrivate::disconnect(const QObject *sender, QObject *s = const_cast<QObject *>(sender); - QMutex *senderMutex = signalSlotLock(sender); - QMutexLocker locker(senderMutex); + QBasicMutex *senderMutex = signalSlotLock(sender); + QBasicMutexLocker locker(senderMutex); - QObjectConnectionListVector *connectionLists = QObjectPrivate::get(s)->connectionLists; - if (!connectionLists) + QObjectPrivate::ConnectionData *scd = QObjectPrivate::get(s)->connections.loadRelaxed(); + if (!scd) return false; - // prevent incoming connections changing the connectionLists while unlocked - ++connectionLists->inUse; - bool success = false; - if (signal_index < 0) { - // remove from all connection lists - for (int sig_index = -1; sig_index < connectionLists->count(); ++sig_index) { - QObjectPrivate::Connection *c = - (*connectionLists)[sig_index].first; - if (disconnectHelper(c, receiver, method_index, slot, senderMutex, disconnectType)) { - success = true; - connectionLists->dirty = true; + { + // prevent incoming connections changing the connections->receivers while unlocked + QObjectPrivate::ConnectionDataPointer connections(scd); + + if (signal_index < 0) { + // remove from all connection lists + for (int sig_index = -1; sig_index < scd->signalVectorCount(); ++sig_index) { + if (disconnectHelper(connections.data(), sig_index, receiver, method_index, slot, senderMutex, disconnectType)) + success = true; } - } - } else if (signal_index < connectionLists->count()) { - QObjectPrivate::Connection *c = - (*connectionLists)[signal_index].first; - if (disconnectHelper(c, receiver, method_index, slot, senderMutex, disconnectType)) { - success = true; - connectionLists->dirty = true; + } else if (signal_index < scd->signalVectorCount()) { + if (disconnectHelper(connections.data(), signal_index, receiver, method_index, slot, senderMutex, disconnectType)) + success = true; } } - --connectionLists->inUse; - Q_ASSERT(connectionLists->inUse >= 0); - if (connectionLists->orphaned && !connectionLists->inUse) - delete connectionLists; - locker.unlock(); if (success) { + scd->cleanOrphanedConnections(s); + QMetaMethod smethod = QMetaObjectPrivate::signal(smeta, signal_index); if (smethod.isValid()) s->disconnectNotify(smethod); @@ -3597,10 +3686,9 @@ void QMetaObject::connectSlotsByName(QObject *o) \a signal must be in the signal index range (see QObjectPrivate::signalIndex()). */ -static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connection *c, void **argv, - QMutexLocker &locker) +static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connection *c, void **argv) { - const int *argumentTypes = c->argumentTypes.load(); + const int *argumentTypes = c->argumentTypes.loadRelaxed(); if (!argumentTypes) { QMetaMethod m = QMetaObjectPrivate::signal(sender->metaObject(), signal); argumentTypes = queuedConnectionTypes(m.parameterTypes()); @@ -3609,7 +3697,7 @@ static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connect if (!c->argumentTypes.testAndSetOrdered(0, argumentTypes)) { if (argumentTypes != &DIRECT_CONNECTION_ONLY) delete [] argumentTypes; - argumentTypes = c->argumentTypes.load(); + argumentTypes = c->argumentTypes.loadRelaxed(); } } if (argumentTypes == &DIRECT_CONNECTION_ONLY) // cannot activate @@ -3617,142 +3705,129 @@ static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connect int nargs = 1; // include return type while (argumentTypes[nargs-1]) ++nargs; - int *types = (int *) malloc(nargs*sizeof(int)); - Q_CHECK_PTR(types); - void **args = (void **) malloc(nargs*sizeof(void *)); - Q_CHECK_PTR(args); + + QBasicMutexLocker locker(signalSlotLock(c->receiver.loadRelaxed())); + if (!c->receiver.loadRelaxed()) { + // the connection has been disconnected before we got the lock + return; + } + if (c->isSlotObject) + c->slotObj->ref(); + locker.unlock(); + + QMetaCallEvent *ev = c->isSlotObject ? + new QMetaCallEvent(c->slotObj, sender, signal, nargs) : + new QMetaCallEvent(c->method_offset, c->method_relative, c->callFunction, sender, signal, nargs); + + void **args = ev->args(); + int *types = ev->types(); + types[0] = 0; // return type - args[0] = 0; // return value + args[0] = nullptr; // return value if (nargs > 1) { for (int n = 1; n < nargs; ++n) types[n] = argumentTypes[n-1]; - locker.unlock(); for (int n = 1; n < nargs; ++n) args[n] = QMetaType::create(types[n], argv[n]); - locker.relock(); - - if (!c->receiver) { - locker.unlock(); - // we have been disconnected while the mutex was unlocked - for (int n = 1; n < nargs; ++n) - QMetaType::destroy(types[n], args[n]); - free(types); - free(args); - locker.relock(); - return; - } } - QMetaCallEvent *ev = c->isSlotObject ? - new QMetaCallEvent(c->slotObj, sender, signal, nargs, types, args) : - new QMetaCallEvent(c->method_offset, c->method_relative, c->callFunction, sender, signal, nargs, types, args); - QCoreApplication::postEvent(c->receiver, ev); -} + locker.relock(); + if (c->isSlotObject) + c->slotObj->destroyIfLastRef(); + if (!c->receiver.loadRelaxed()) { + // the connection has been disconnected while we were unlocked + locker.unlock(); + delete ev; + return; + } -/*! - \internal - */ -void QMetaObject::activate(QObject *sender, const QMetaObject *m, int local_signal_index, - void **argv) -{ - activate(sender, QMetaObjectPrivate::signalOffset(m), local_signal_index, argv); + QCoreApplication::postEvent(c->receiver.loadRelaxed(), ev); } -/*! - \internal - */ -void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_index, void **argv) +template <bool callbacks_enabled> +void doActivate(QObject *sender, int signal_index, void **argv) { - int signal_index = signalOffset + local_signal_index; + QObjectPrivate *sp = QObjectPrivate::get(sender); - if (sender->d_func()->blockSig) + if (sp->blockSig) return; Q_TRACE_SCOPE(QMetaObject_activate, sender, signal_index); - if (sender->d_func()->isDeclarativeSignalConnected(signal_index) + if (sp->isDeclarativeSignalConnected(signal_index) && QAbstractDeclarativeData::signalEmitted) { Q_TRACE_SCOPE(QMetaObject_activate_declarative_signal, sender, signal_index); - QAbstractDeclarativeData::signalEmitted(sender->d_func()->declarativeData, sender, + QAbstractDeclarativeData::signalEmitted(sp->declarativeData, sender, signal_index, argv); } - if (!sender->d_func()->isSignalConnected(signal_index, /*checkDeclarative =*/ false) - && !qt_signal_spy_callback_set.signal_begin_callback - && !qt_signal_spy_callback_set.signal_end_callback) { - // The possible declarative connection is done, and nothing else is connected, so: - return; - } + const QSignalSpyCallbackSet *signal_spy_set = callbacks_enabled ? qt_signal_spy_callback_set.loadAcquire() : nullptr; void *empty_argv[] = { nullptr }; if (!argv) argv = empty_argv; - if (qt_signal_spy_callback_set.signal_begin_callback != 0) { - qt_signal_spy_callback_set.signal_begin_callback(sender, signal_index, argv); + if (!sp->maybeSignalConnected(signal_index)) { + // The possible declarative connection is done, and nothing else is connected + if (callbacks_enabled && signal_spy_set->signal_begin_callback != nullptr) + signal_spy_set->signal_begin_callback(sender, signal_index, argv); + if (callbacks_enabled && signal_spy_set->signal_end_callback != nullptr) + signal_spy_set->signal_end_callback(sender, signal_index); + return; } - { - QMutexLocker locker(signalSlotLock(sender)); - struct ConnectionListsRef { - QObjectConnectionListVector *connectionLists; - ConnectionListsRef(QObjectConnectionListVector *connectionLists) : connectionLists(connectionLists) - { - if (connectionLists) - ++connectionLists->inUse; - } - ~ConnectionListsRef() - { - if (!connectionLists) - return; - - --connectionLists->inUse; - Q_ASSERT(connectionLists->inUse >= 0); - if (connectionLists->orphaned) { - if (!connectionLists->inUse) - delete connectionLists; - } - } + if (callbacks_enabled && signal_spy_set->signal_begin_callback != nullptr) + signal_spy_set->signal_begin_callback(sender, signal_index, argv); - QObjectConnectionListVector *operator->() const { return connectionLists; } - }; - ConnectionListsRef connectionLists = sender->d_func()->connectionLists; - if (!connectionLists.connectionLists) { - locker.unlock(); - if (qt_signal_spy_callback_set.signal_end_callback != 0) - qt_signal_spy_callback_set.signal_end_callback(sender, signal_index); - return; - } + bool senderDeleted = false; + { + Q_ASSERT(sp->connections.loadAcquire()); + QObjectPrivate::ConnectionDataPointer connections(sp->connections.loadRelaxed()); + QObjectPrivate::SignalVector *signalVector = connections->signalVector.loadRelaxed(); const QObjectPrivate::ConnectionList *list; - if (signal_index < connectionLists->count()) - list = &connectionLists->at(signal_index); + if (signal_index < signalVector->count()) + list = &signalVector->at(signal_index); else - list = &connectionLists->allsignals; + list = &signalVector->at(-1); Qt::HANDLE currentThreadId = QThread::currentThreadId(); + bool inSenderThread = currentThreadId == QObjectPrivate::get(sender)->threadData->threadId.loadRelaxed(); + // We need to check against the highest connection id to ensure that signals added + // during the signal emission are not emitted in this emission. + uint highestConnectionId = connections->currentConnectionId.loadRelaxed(); do { - QObjectPrivate::Connection *c = list->first; - if (!c) continue; - // We need to check against last here to ensure that signals added - // during the signal emission are not emitted in this emission. - QObjectPrivate::Connection *last = list->last; + QObjectPrivate::Connection *c = list->first.loadRelaxed(); + if (!c) + continue; do { - if (!c->receiver) + QObject * const receiver = c->receiver.loadRelaxed(); + if (!receiver) continue; - QObject * const receiver = c->receiver; - const bool receiverInSameThread = currentThreadId == receiver->d_func()->threadData->threadId.load(); + QThreadData *td = c->receiverThreadData.loadRelaxed(); + if (!td) + continue; + + bool receiverInSameThread; + if (inSenderThread) { + receiverInSameThread = currentThreadId == td->threadId.loadRelaxed(); + } else { + // need to lock before reading the threadId, because moveToThread() could interfere + QMutexLocker lock(signalSlotLock(receiver)); + receiverInSameThread = currentThreadId == td->threadId.loadRelaxed(); + } + // determine if this connection should be sent immediately or // put into the event queue if ((c->connectionType == Qt::AutoConnection && !receiverInSameThread) || (c->connectionType == Qt::QueuedConnection)) { - queued_activate(sender, signal_index, c, argv, locker); + queued_activate(sender, signal_index, c, argv); continue; #if QT_CONFIG(thread) } else if (c->connectionType == Qt::BlockingQueuedConnection) { @@ -3763,92 +3838,113 @@ void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_i receiver->metaObject()->className(), receiver); } QSemaphore semaphore; - QMetaCallEvent *ev = c->isSlotObject ? - new QMetaCallEvent(c->slotObj, sender, signal_index, 0, 0, argv, &semaphore) : - new QMetaCallEvent(c->method_offset, c->method_relative, c->callFunction, sender, signal_index, 0, 0, argv, &semaphore); - QCoreApplication::postEvent(receiver, ev); - locker.unlock(); + { + QBasicMutexLocker locker(signalSlotLock(sender)); + if (!c->receiver.loadAcquire()) + continue; + QMetaCallEvent *ev = c->isSlotObject ? + new QMetaCallEvent(c->slotObj, sender, signal_index, argv, &semaphore) : + new QMetaCallEvent(c->method_offset, c->method_relative, c->callFunction, + sender, signal_index, argv, &semaphore); + QCoreApplication::postEvent(receiver, ev); + } semaphore.acquire(); - locker.relock(); continue; #endif } - QConnectionSenderSwitcher sw; + QObjectPrivate::Sender senderData(receiverInSameThread ? receiver : nullptr, sender, signal_index); - if (receiverInSameThread) { - sw.switchSender(receiver, sender, signal_index); - } if (c->isSlotObject) { c->slotObj->ref(); - QScopedPointer<QtPrivate::QSlotObjectBase, QSlotObjectBaseDeleter> obj(c->slotObj); - locker.unlock(); + + struct Deleter { + void operator()(QtPrivate::QSlotObjectBase *slot) const { + if (slot) slot->destroyIfLastRef(); + } + }; + const std::unique_ptr<QtPrivate::QSlotObjectBase, Deleter> obj{c->slotObj}; { - Q_TRACE_SCOPE(QMetaObject_activate_slot_functor, obj.data()); + Q_TRACE_SCOPE(QMetaObject_activate_slot_functor, obj.get()); obj->call(receiver, argv); } - - // Make sure the slot object gets destroyed before the mutex is locked again, as the - // destructor of the slot object might also lock a mutex from the signalSlotLock() mutex pool, - // and that would deadlock if the pool happens to return the same mutex. - obj.reset(); - - locker.relock(); } else if (c->callFunction && c->method_offset <= receiver->metaObject()->methodOffset()) { //we compare the vtable to make sure we are not in the destructor of the object. - const int methodIndex = c->method(); const int method_relative = c->method_relative; const auto callFunction = c->callFunction; - locker.unlock(); - if (qt_signal_spy_callback_set.slot_begin_callback != 0) - qt_signal_spy_callback_set.slot_begin_callback(receiver, methodIndex, argv); + const int methodIndex = (Q_HAS_TRACEPOINTS || callbacks_enabled) ? c->method() : 0; + if (callbacks_enabled && signal_spy_set->slot_begin_callback != nullptr) + signal_spy_set->slot_begin_callback(receiver, methodIndex, argv); { Q_TRACE_SCOPE(QMetaObject_activate_slot, receiver, methodIndex); callFunction(receiver, QMetaObject::InvokeMetaMethod, method_relative, argv); } - if (qt_signal_spy_callback_set.slot_end_callback != 0) - qt_signal_spy_callback_set.slot_end_callback(receiver, methodIndex); - locker.relock(); + if (callbacks_enabled && signal_spy_set->slot_end_callback != nullptr) + signal_spy_set->slot_end_callback(receiver, methodIndex); } else { const int method = c->method_relative + c->method_offset; - locker.unlock(); - if (qt_signal_spy_callback_set.slot_begin_callback != 0) { - qt_signal_spy_callback_set.slot_begin_callback(receiver, method, argv); + if (callbacks_enabled && signal_spy_set->slot_begin_callback != nullptr) { + signal_spy_set->slot_begin_callback(receiver, method, argv); } { Q_TRACE_SCOPE(QMetaObject_activate_slot, receiver, method); - metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv); + QMetaObject::metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv); } - if (qt_signal_spy_callback_set.slot_end_callback != 0) - qt_signal_spy_callback_set.slot_end_callback(receiver, method); - - locker.relock(); + if (callbacks_enabled && signal_spy_set->slot_end_callback != nullptr) + signal_spy_set->slot_end_callback(receiver, method); } + } while ((c = c->nextConnectionList.loadRelaxed()) != nullptr && c->id <= highestConnectionId); - if (connectionLists->orphaned) - break; - } while (c != last && (c = c->nextConnectionList) != 0); - - if (connectionLists->orphaned) - break; - } while (list != &connectionLists->allsignals && + } while (list != &signalVector->at(-1) && //start over for all signals; - ((list = &connectionLists->allsignals), true)); + ((list = &signalVector->at(-1)), true)); + if (connections->currentConnectionId.loadRelaxed() == 0) + senderDeleted = true; } + if (!senderDeleted) { + sp->connections.loadRelaxed()->cleanOrphanedConnections(sender); - if (qt_signal_spy_callback_set.signal_end_callback != 0) - qt_signal_spy_callback_set.signal_end_callback(sender, signal_index); + if (callbacks_enabled && signal_spy_set->signal_end_callback != nullptr) + signal_spy_set->signal_end_callback(sender, signal_index); + } } /*! \internal + */ +void QMetaObject::activate(QObject *sender, const QMetaObject *m, int local_signal_index, + void **argv) +{ + int signal_index = local_signal_index + QMetaObjectPrivate::signalOffset(m); + + if (Q_UNLIKELY(qt_signal_spy_callback_set.loadRelaxed())) + doActivate<true>(sender, signal_index, argv); + else + doActivate<false>(sender, signal_index, argv); +} + +/*! + \internal + */ +void QMetaObject::activate(QObject *sender, int signalOffset, int local_signal_index, void **argv) +{ + int signal_index = signalOffset + local_signal_index; + + if (Q_UNLIKELY(qt_signal_spy_callback_set.loadRelaxed())) + doActivate<true>(sender, signal_index, argv); + else + doActivate<false>(sender, signal_index, argv); + } + +/*! + \internal signal_index comes from indexOfMethod() */ void QMetaObject::activate(QObject *sender, int signal_index, void **argv) @@ -3861,7 +3957,7 @@ void QMetaObject::activate(QObject *sender, int signal_index, void **argv) /*! \internal - Returns the signal index used in the internal connectionLists vector. + Returns the signal index used in the internal connections->receivers vector. It is different from QMetaObject::indexOfSignal(): indexOfSignal is the same as indexOfMethod while QObjectPrivate::signalIndex is smaller because it doesn't give index to slots. @@ -4044,6 +4140,7 @@ static void dumpRecursive(int level, const QObject *object) } } +#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0) /*! \overload \obsolete @@ -4057,6 +4154,7 @@ void QObject::dumpObjectTree() { const_cast<const QObject *>(this)->dumpObjectTree(); } +#endif /*! Dumps a tree of children to the debug output. @@ -4071,6 +4169,7 @@ void QObject::dumpObjectTree() const dumpRecursive(0, this); } +#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0) /*! \overload \obsolete @@ -4085,6 +4184,7 @@ void QObject::dumpObjectInfo() { const_cast<const QObject *>(this)->dumpObjectInfo(); } +#endif /*! Dumps information about signal connections, etc. for this object @@ -4101,37 +4201,40 @@ void QObject::dumpObjectInfo() const objectName().isEmpty() ? "unnamed" : objectName().toLocal8Bit().data()); Q_D(const QObject); - QMutexLocker locker(signalSlotLock(this)); + QBasicMutexLocker locker(signalSlotLock(this)); // first, look for connections where this object is the sender qDebug(" SIGNALS OUT"); - if (d->connectionLists) { - for (int signal_index = 0; signal_index < d->connectionLists->count(); ++signal_index) { + QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed(); + if (cd && cd->signalVectorCount()) { + QObjectPrivate::SignalVector *signalVector = cd->signalVector.loadRelaxed(); + for (int signal_index = 0; signal_index < signalVector->count(); ++signal_index) { + const QObjectPrivate::Connection *c = signalVector->at(signal_index).first.loadRelaxed(); + if (!c) + continue; const QMetaMethod signal = QMetaObjectPrivate::signal(metaObject(), signal_index); qDebug(" signal: %s", signal.methodSignature().constData()); // receivers - const QObjectPrivate::Connection *c = - d->connectionLists->at(signal_index).first; while (c) { - if (!c->receiver) { + if (!c->receiver.loadRelaxed()) { qDebug(" <Disconnected receiver>"); - c = c->nextConnectionList; + c = c->nextConnectionList.loadRelaxed(); continue; } if (c->isSlotObject) { qDebug(" <functor or function pointer>"); - c = c->nextConnectionList; + c = c->nextConnectionList.loadRelaxed(); continue; } - const QMetaObject *receiverMetaObject = c->receiver->metaObject(); + const QMetaObject *receiverMetaObject = c->receiver.loadRelaxed()->metaObject(); const QMetaMethod method = receiverMetaObject->method(c->method()); qDebug(" --> %s::%s %s", receiverMetaObject->className(), - c->receiver->objectName().isEmpty() ? "unnamed" : qPrintable(c->receiver->objectName()), + c->receiver.loadRelaxed()->objectName().isEmpty() ? "unnamed" : qPrintable(c->receiver.loadRelaxed()->objectName()), method.methodSignature().constData()); - c = c->nextConnectionList; + c = c->nextConnectionList.loadRelaxed(); } } } else { @@ -4141,8 +4244,8 @@ void QObject::dumpObjectInfo() const // now look for connections where this object is the receiver qDebug(" SIGNALS IN"); - if (d->senders) { - for (QObjectPrivate::Connection *s = d->senders; s; s = s->next) { + if (cd && cd->senders) { + for (QObjectPrivate::Connection *s = cd->senders; s; s = s->next) { QByteArray slotName = QByteArrayLiteral("<unknown>"); if (!s->isSlotObject) { const QMetaMethod slot = metaObject()->method(s->method()); @@ -4159,16 +4262,22 @@ void QObject::dumpObjectInfo() const } #ifndef QT_NO_USERDATA +static QBasicAtomicInteger<uint> user_data_registration = Q_BASIC_ATOMIC_INITIALIZER(0); + /*! \internal */ uint QObject::registerUserData() { - static int user_data_registration = 0; - return user_data_registration++; + return user_data_registration.fetchAndAddRelaxed(1); } /*! + \fn QObjectUserData::QObjectUserData() + \internal + */ + +/*! \internal */ QObjectUserData::~QObjectUserData() @@ -4489,6 +4598,24 @@ QDebug operator<<(QDebug dbg, const QObject *o) Q_NAMESPACE makes an external variable, \c{staticMetaObject}, available. \c{staticMetaObject} is of type QMetaObject and provides access to the enums declared with Q_ENUM_NS/Q_FLAG_NS. + + \sa Q_NAMESPACE_EXPORT +*/ + +/*! + \macro Q_NAMESPACE_EXPORT(EXPORT_MACRO) + \relates QObject + \since 5.14 + + The Q_NAMESPACE_EXPORT macro can be used to add QMetaObject capabilities + to a namespace. + + It works exactly like the Q_NAMESPACE macro. However, the external + \c{staticMetaObject} variable that gets defined in the namespace + is declared with the supplied \c{EXPORT_MACRO} qualifier. This is + useful if the object needs to be exported from a dynamic library. + + \sa Q_NAMESPACE, {Creating Shared Libraries} */ /*! @@ -4873,37 +5000,39 @@ QMetaObject::Connection QObjectPrivate::connectImpl(const QObject *sender, int s QOrderedMutexLocker locker(signalSlotLock(sender), signalSlotLock(receiver)); - if (type & Qt::UniqueConnection && slot) { - QObjectConnectionListVector *connectionLists = QObjectPrivate::get(s)->connectionLists; - if (connectionLists && connectionLists->count() > signal_index) { - const QObjectPrivate::Connection *c2 = - (*connectionLists)[signal_index].first; + if (type & Qt::UniqueConnection && slot && QObjectPrivate::get(s)->connections.loadRelaxed()) { + QObjectPrivate::ConnectionData *connections = QObjectPrivate::get(s)->connections.loadRelaxed(); + if (connections->signalVectorCount() > signal_index) { + const QObjectPrivate::Connection *c2 = connections->signalVector.loadRelaxed()->at(signal_index).first.loadRelaxed(); while (c2) { - if (c2->receiver == receiver && c2->isSlotObject && c2->slotObj->compare(slot)) { + if (c2->receiver.loadRelaxed() == receiver && c2->isSlotObject && c2->slotObj->compare(slot)) { slotObj->destroyIfLastRef(); return QMetaObject::Connection(); } - c2 = c2->nextConnectionList; + c2 = c2->nextConnectionList.loadRelaxed(); } } type = static_cast<Qt::ConnectionType>(type ^ Qt::UniqueConnection); } - QScopedPointer<QObjectPrivate::Connection> c(new QObjectPrivate::Connection); + std::unique_ptr<QObjectPrivate::Connection> c{new QObjectPrivate::Connection}; c->sender = s; c->signal_index = signal_index; - c->receiver = r; + QThreadData *td = r->d_func()->threadData; + td->ref(); + c->receiverThreadData.storeRelaxed(td); + c->receiver.storeRelaxed(r); c->slotObj = slotObj; c->connectionType = type; c->isSlotObject = true; if (types) { - c->argumentTypes.store(types); + c->argumentTypes.storeRelaxed(types); c->ownArgumentTypes = false; } - QObjectPrivate::get(s)->addConnection(signal_index, c.data()); - QMetaObject::Connection ret(c.take()); + QObjectPrivate::get(s)->addConnection(signal_index, c.get()); + QMetaObject::Connection ret(c.release()); locker.unlock(); QMetaMethod method = QMetaObjectPrivate::signal(senderMetaObject, signal_index); @@ -4925,35 +5054,35 @@ bool QObject::disconnect(const QMetaObject::Connection &connection) { QObjectPrivate::Connection *c = static_cast<QObjectPrivate::Connection *>(connection.d_ptr); - if (!c || !c->receiver) + if (!c) + return false; + QObject *receiver = c->receiver.loadRelaxed(); + if (!receiver) return false; - QMutex *senderMutex = signalSlotLock(c->sender); - QMutex *receiverMutex = signalSlotLock(c->receiver); + QBasicMutex *senderMutex = signalSlotLock(c->sender); + QBasicMutex *receiverMutex = signalSlotLock(receiver); + QObjectPrivate::ConnectionData *connections; { QOrderedMutexLocker locker(senderMutex, receiverMutex); - QObjectConnectionListVector *connectionLists = QObjectPrivate::get(c->sender)->connectionLists; - Q_ASSERT(connectionLists); - connectionLists->dirty = true; + // load receiver once again and recheck to ensure nobody else has removed the connection in the meantime + receiver = c->receiver.loadRelaxed(); + if (!receiver) + return false; - *c->prev = c->next; - if (c->next) - c->next->prev = c->prev; - c->receiver = 0; + connections = QObjectPrivate::get(c->sender)->connections.loadRelaxed(); + Q_ASSERT(connections); + connections->removeConnection(c); } - // destroy the QSlotObject, if possible - if (c->isSlotObject) { - c->slotObj->destroyIfLastRef(); - c->isSlotObject = false; - } + connections->cleanOrphanedConnections(c->sender); c->sender->disconnectNotify(QMetaObjectPrivate::signal(c->sender->metaObject(), c->signal_index)); - const_cast<QMetaObject::Connection &>(connection).d_ptr = 0; + const_cast<QMetaObject::Connection &>(connection).d_ptr = nullptr; c->deref(); // has been removed from the QMetaObject::Connection object return true; @@ -5036,7 +5165,7 @@ bool QObject::disconnectImpl(const QObject *sender, void **signal, const QObject } if (!senderMetaObject) { qWarning("QObject::disconnect: signal not found in %s", sender->metaObject()->className()); - return QMetaObject::Connection(0); + return false; } signal_index += QMetaObjectPrivate::signalOffset(senderMetaObject); } @@ -5135,7 +5264,7 @@ bool QMetaObject::Connection::isConnected_helper() const Q_ASSERT(d_ptr); // we're only called from operator RestrictedBool() const QObjectPrivate::Connection *c = static_cast<QObjectPrivate::Connection *>(d_ptr); - return c->receiver; + return c->receiver.loadRelaxed(); } |