qobject.cpp

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/****************************************************************************
**
** Copyright (C) 2021 The Qt Company Ltd.
** Copyright (C) 2016 Intel Corporation.
** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com>
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
 
#include "qobject.h"
#include "qobject_p.h"
#include "qmetaobject_p.h"
 
#include "qabstracteventdispatcher.h"
#include "qabstracteventdispatcher_p.h"
#include "qcoreapplication.h"
#include "qcoreapplication_p.h"
#include "qloggingcategory.h"
#include "qvariant.h"
#include "qmetaobject.h"
#if QT_CONFIG(regularexpression)
#  include <qregularexpression.h>
#endif
#include <qthread.h>
#include <private/qthread_p.h>
#include <qdebug.h>
#include <qpair.h>
#include <qvarlengtharray.h>
#include <qscopeguard.h>
#include <qset.h>
#if QT_CONFIG(thread)
#include <qsemaphore.h>
#endif
#include <qsharedpointer.h>
 
#include <private/qorderedmutexlocker_p.h>
#include <private/qhooks_p.h>
#include <qtcore_tracepoints_p.h>
 
#include <new>
#include <mutex>
#include <memory>
 
#include <ctype.h>
#include <limits.h>
 
QT_BEGIN_NAMESPACE
 
static int DIRECT_CONNECTION_ONLY = 0;
 
Q_LOGGING_CATEGORY(lcConnectSlotsByName, "qt.core.qmetaobject.connectslotsbyname")
Q_LOGGING_CATEGORY(lcConnect, "qt.core.qobject.connect")
 
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()
{
}
 
QAbstractDynamicMetaObject::~QAbstractDynamicMetaObject()
{
}
 
static int *queuedConnectionTypes(const QMetaMethod &method)
{
    const auto parameterCount = method.parameterCount();
    int *typeIds = new int[parameterCount + 1];
    Q_CHECK_PTR(typeIds);
    for (int i = 0; i < parameterCount; ++i) {
        const QMetaType metaType = method.parameterMetaType(i);
        if (metaType.flags() & QMetaType::IsPointer)
            typeIds[i] = QMetaType::VoidStar;
        else
            typeIds[i] = metaType.id();
        if (!typeIds[i]) {
            const QByteArray typeName = method.parameterTypeName(i);
            qCWarning(lcConnect,
                      "QObject::connect: Cannot queue arguments of type '%s'\n"
                      "(Make sure '%s' is registered using qRegisterMetaType().)",
                      typeName.constData(), typeName.constData());
            delete[] typeIds;
            return nullptr;
        }
    }
    typeIds[parameterCount] = 0;
 
    return typeIds;
}
 
static int *queuedConnectionTypes(const QArgumentType *argumentTypes, int argc)
{
    auto types = std::make_unique<int[]>(argc + 1);
    for (int i = 0; i < argc; ++i) {
        const QArgumentType &type = argumentTypes[i];
        if (type.type())
            types[i] = type.type();
        else if (type.name().endsWith('*'))
            types[i] = QMetaType::VoidStar;
        else
            types[i] = QMetaType::fromName(type.name()).id();
 
        if (!types[i]) {
            qCWarning(lcConnect,
                      "QObject::connect: Cannot queue arguments of type '%s'\n"
                      "(Make sure '%s' is registered using qRegisterMetaType().)",
                      type.name().constData(), type.name().constData());
            return nullptr;
        }
    }
    types[argc] = 0;
 
    return types.release();
}
 
static QBasicMutex _q_ObjectMutexPool[131];
 
static inline QBasicMutex *signalSlotLock(const QObject *o)
{
    return &_q_ObjectMutexPool[uint(quintptr(o)) % sizeof(_q_ObjectMutexPool)/sizeof(QBasicMutex)];
}
 
void (*QAbstractDeclarativeData::destroyed)(QAbstractDeclarativeData *, QObject *) = nullptr;
void (*QAbstractDeclarativeData::signalEmitted)(QAbstractDeclarativeData *, QObject *, int, void **) = nullptr;
int  (*QAbstractDeclarativeData::receivers)(QAbstractDeclarativeData *, const QObject *, int) = nullptr;
bool (*QAbstractDeclarativeData::isSignalConnected)(QAbstractDeclarativeData *, const QObject *, int) = nullptr;
void (*QAbstractDeclarativeData::setWidgetParent)(QObject *, QObject *) = nullptr;
 
QObjectData::~QObjectData() {}
 
QMetaObject *QObjectData::dynamicMetaObject() const
{
    return metaObject->toDynamicMetaObject(q_ptr);
}
 
QObjectPrivate::QObjectPrivate(int version)
    : threadData(nullptr), currentChildBeingDeleted(nullptr)
{
    checkForIncompatibleLibraryVersion(version);
 
    // QObjectData initialization
    q_ptr = nullptr;
    parent = nullptr;                           // no parent yet. It is set by setParent()
    isWidget = false;                           // assume not a widget object
    blockSig = false;                           // not blocking signals
    wasDeleted = false;                         // double-delete catcher
    isDeletingChildren = false;                 // set by deleteChildren()
    sendChildEvents = true;                     // if we should send ChildAdded and ChildRemoved events to parent
    receiveChildEvents = true;
    postedEvents = 0;
    extraData = nullptr;
    metaObject = nullptr;
    isWindow = false;
    deleteLaterCalled = false;
}
 
QObjectPrivate::~QObjectPrivate()
{
    auto thisThreadData = threadData.loadRelaxed();
    if (extraData && !extraData->runningTimers.isEmpty()) {
        if (Q_LIKELY(thisThreadData->thread.loadAcquire() == QThread::currentThread())) {
            // unregister pending timers
            if (thisThreadData->hasEventDispatcher())
                thisThreadData->eventDispatcher.loadRelaxed()->unregisterTimers(q_ptr);
 
            // release the timer ids back to the pool
            for (int i = 0; i < extraData->runningTimers.size(); ++i)
                QAbstractEventDispatcherPrivate::releaseTimerId(extraData->runningTimers.at(i));
        } else {
            qWarning("QObject::~QObject: Timers cannot be stopped from another thread");
        }
    }
 
    if (postedEvents)
        QCoreApplication::removePostedEvents(q_ptr, 0);
 
    thisThreadData->deref();
 
    if (metaObject)
        metaObject->objectDestroyed(q_ptr);
 
    delete extraData;
}
 
static void computeOffsets(const QMetaObject *metaobject, int *signalOffset, int *methodOffset)
{
    *signalOffset = *methodOffset = 0;
    const QMetaObject *m = metaobject->d.superdata;
    while (m) {
        const QMetaObjectPrivate *d = QMetaObjectPrivate::get(m);
        *methodOffset += d->methodCount;
        Q_ASSERT(d->revision >= 4);
        *signalOffset += d->signalCount;
        m = m->d.superdata;
    }
}
 
// Used by QAccessibleWidget
bool QObjectPrivate::isSender(const QObject *receiver, const char *signal) const
{
    Q_Q(const QObject);
    int signal_index = signalIndex(signal);
    ConnectionData *cd = connections.loadRelaxed();
    if (signal_index < 0 || !cd)
        return false;
    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;
}
 
// Used by QAccessibleWidget
QObjectList QObjectPrivate::receiverList(const char *signal) const
{
    QObjectList returnValue;
    int signal_index = signalIndex(signal);
    ConnectionData *cd = connections.loadRelaxed();
    if (signal_index < 0 || !cd)
        return returnValue;
    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;
}
 
// Used by QAccessibleWidget
QObjectList QObjectPrivate::senderList() const
{
    QObjectList returnValue;
    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;
}
 
void QObjectPrivate::addConnection(int signal, Connection *c)
{
    Q_ASSERT(c->sender == q_ptr);
    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.storeRelaxed(c);
    }
    c->id = ++cd->currentConnectionId;
    c->prevConnectionList = connectionList.last.loadRelaxed();
    connectionList.last.storeRelaxed(c);
 
    QObjectPrivate *rd = QObjectPrivate::get(c->receiver.loadRelaxed());
    rd->ensureConnectionData();
 
    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);
 
#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
    Connection *o = nullptr;
    /* No ABA issue here: When adding a node, we only care about the list head, it doesn't
     * matter if the tail changes.
     */
    do {
        o = orphaned.loadRelaxed();
        c->nextInOrphanList = o;
    } while (!orphaned.testAndSetRelease(o, 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::ConnectionData::cleanOrphanedConnectionsImpl(QObject *sender, LockPolicy lockPolicy)
{
    QBasicMutex *senderMutex = signalSlotLock(sender);
    ConnectionOrSignalVector *c = nullptr;
    {
        std::unique_lock<QBasicMutex> lock(*senderMutex, std::defer_lock_t{});
        if (lockPolicy == NeedToLock)
            lock.lock();
        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.fetchAndStoreRelaxed(nullptr);
    }
    if (c) {
        // Deleting c might run arbitrary user code, so we must not hold the lock
        if (lockPolicy == AlreadyLockedAndTemporarilyReleasingLock) {
            senderMutex->unlock();
            deleteOrphaned(c);
            senderMutex->lock();
        } else {
            deleteOrphaned(c);
        }
    }
}
 
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;
    }
}
 
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();
        }
    }
    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;
}
 
QAbstractMetaCallEvent::~QAbstractMetaCallEvent()
{
#if QT_CONFIG(thread)
    if (semaphore_)
        semaphore_->release();
#endif
}
 
inline void QMetaCallEvent::allocArgs()
{
    if (!d.nargs_)
        return;
 
    constexpr size_t each = sizeof(void*) + sizeof(QMetaType);
    void *const memory = d.nargs_ * each > sizeof(prealloc_) ?
        calloc(d.nargs_, each) : prealloc_;
 
    Q_CHECK_PTR(memory);
    d.args_ = static_cast<void **>(memory);
}
 
QMetaCallEvent::QMetaCallEvent(ushort method_offset, ushort method_relative,
                               QObjectPrivate::StaticMetaCallFunction callFunction,
                               const QObject *sender, int signalId,
                               void **args, QSemaphore *semaphore)
    : QAbstractMetaCallEvent(sender, signalId, semaphore),
      d({nullptr, args, callFunction, 0, method_offset, method_relative}),
      prealloc_()
{
}
 
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();
}
 
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();
}
 
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 (d.slotObj_)
        d.slotObj_->ref();
    allocArgs();
}
 
QMetaCallEvent::~QMetaCallEvent()
{
    if (d.nargs_) {
        QMetaType *t = types();
        for (int i = 0; i < d.nargs_; ++i) {
            if (t[i].isValid() && d.args_[i])
                t[i].destroy(d.args_[i]);
        }
        if (reinterpret_cast<void *>(d.args_) != reinterpret_cast<void *>(prealloc_))
            free(d.args_);
    }
    if (d.slotObj_)
        d.slotObj_->destroyIfLastRef();
}
 
void QMetaCallEvent::placeMetaCall(QObject *object)
{
    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,
                              d.method_offset_ + d.method_relative_, d.args_);
    }
}
 
/*****************************************************************************
  QObject member functions
 *****************************************************************************/
 
// check the constructor's parent thread argument
static bool check_parent_thread(QObject *parent,
                                QThreadData *parentThreadData,
                                QThreadData *currentThreadData)
{
    if (parent && parentThreadData != currentThreadData) {
        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(),
                 parent,
                 parentThread ? parentThread->metaObject()->className() : "QThread",
                 parentThread,
                 currentThread ? currentThread->metaObject()->className() : "QThread",
                 currentThread);
        return false;
    }
    return true;
}
 
QObject::QObject(QObject *parent)
    : QObject(*new QObjectPrivate, 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;
    auto threadData = (parent && !parent->thread()) ? parent->d_func()->threadData.loadRelaxed() : QThreadData::current();
    threadData->ref();
    d->threadData.storeRelaxed(threadData);
    if (parent) {
        QT_TRY {
            if (!check_parent_thread(parent, parent ? parent->d_func()->threadData.loadRelaxed() : nullptr, threadData))
                parent = nullptr;
            if (d->isWidget) {
                if (parent) {
                    d->parent = parent;
                    d->parent->d_func()->children.append(this);
                }
                // no events sent here, this is done at the end of the QWidget constructor
            } else {
                setParent(parent);
            }
        } QT_CATCH(...) {
            threadData->deref();
            QT_RETHROW;
        }
    }
    if (Q_UNLIKELY(qtHookData[QHooks::AddQObject]))
        reinterpret_cast<QHooks::AddQObjectCallback>(qtHookData[QHooks::AddQObject])(this);
    Q_TRACE(QObject_ctor, this);
}
 
void QObjectPrivate::clearBindingStorage()
{
    bindingStorage.clear();
}
 
QObject::~QObject()
{
    Q_D(QObject);
    d->wasDeleted = true;
    d->blockSig = 0; // unblock signals so we always emit destroyed()
 
    // If we reached this point, we need to clear the binding data
    // as the corresponding properties are no longer useful
    d->clearBindingStorage();
 
    QtSharedPointer::ExternalRefCountData *sharedRefcount = d->sharedRefcount.loadRelaxed();
    if (sharedRefcount) {
        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.storeRelaxed(0);
        if (!sharedRefcount->weakref.deref())
            delete sharedRefcount;
    }
 
    if (!d->isWidget && d->isSignalConnected(0)) {
        emit destroyed(this);
    }
 
    if (d->declarativeData && QAbstractDeclarativeData::destroyed)
        QAbstractDeclarativeData::destroyed(d->declarativeData, this);
 
    QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed();
    if (cd) {
        if (cd->currentSender) {
            cd->currentSender->receiverDeleted();
            cd->currentSender = nullptr;
        }
 
        QBasicMutex *signalSlotMutex = signalSlotLock(this);
        QBasicMutexLocker locker(signalSlotMutex);
 
        // disconnect all receivers
        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 == connectionList.first.loadAcquire() && c->receiver.loadAcquire()) {
                    cd->removeConnection(c);
                    Q_ASSERT(connectionList.first.loadRelaxed() != c);
                }
                if (needToUnlock)
                    m->unlock();
            }
        }
 
        /* Disconnect all senders:
         */
        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));
            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 != cd->senders) {
                // We hold the wrong mutex
                Q_ASSERT(needToUnlock);
                m->unlock();
                continue;
            }
 
            QObjectPrivate::ConnectionData *senderData = sender->d_func()->connections.loadRelaxed();
            Q_ASSERT(senderData);
 
            QtPrivate::QSlotObjectBase *slotObj = nullptr;
            if (node->isSlotObject) {
                slotObj = node->slotObj;
                node->isSlotObject = false;
            }
 
            senderData->removeConnection(node);
            /*
              When we unlock, another thread has the chance to delete/modify sender data.
              Thus we need to call cleanOrphanedConnections before unlocking. We use the
              variant of the function which assumes that the lock is already held to avoid
              a deadlock.
              We need to hold m, the sender lock. Considering that we might execute arbitrary user
              code, we should already release the signalSlotMutex here – unless they are the same.
            */
            const bool locksAreTheSame = signalSlotMutex == m;
            if (!locksAreTheSame)
                locker.unlock();
            senderData->cleanOrphanedConnections(
                        sender,
                        QObjectPrivate::ConnectionData::AlreadyLockedAndTemporarilyReleasingLock
                        );
            if (needToUnlock)
                m->unlock();
 
            if (locksAreTheSame) // otherwise already unlocked
                locker.unlock();
            if (slotObj)
                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();
 
    if (Q_UNLIKELY(qtHookData[QHooks::RemoveQObject]))
        reinterpret_cast<QHooks::RemoveQObjectCallback>(qtHookData[QHooks::RemoveQObject])(this);
 
    Q_TRACE(QObject_dtor, this);
 
    if (d->parent)        // remove it from parent object
        d->setParent_helper(nullptr);
}
 
QObjectPrivate::Connection::~Connection()
{
    if (ownArgumentTypes) {
        const int *v = argumentTypes.loadRelaxed();
        if (v != &DIRECT_CONNECTION_ONLY)
            delete[] v;
    }
    if (isSlotObject)
        slotObj->destroyIfLastRef();
}
 
 
QString QObject::objectName() const
{
    Q_D(const QObject);
#if QT_CONFIG(thread)
    if (QThread::currentThreadId() != d->threadData.loadRelaxed()->threadId.loadRelaxed()) // Unsafe code path
        return d->extraData ? d->extraData->objectName.valueBypassingBindings() : QString();
#endif
    if (!d->extraData && QtPrivate::isAnyBindingEvaluating()) {
        QObjectPrivate *dd = const_cast<QObjectPrivate *>(d);
        // extraData is mutable, so this should be safe
        dd->extraData = new QObjectPrivate::ExtraData(dd);
    }
    return d->extraData ? d->extraData->objectName : QString();
}
 
/*
    Sets the object's name to \a name.
*/
void QObject::setObjectName(const QString &name)
{
    Q_D(QObject);
 
    if (!d->extraData)
        d->extraData = new QObjectPrivate::ExtraData(d);
 
    d->extraData->objectName.removeBindingUnlessInWrapper();
 
    if (d->extraData->objectName != name) {
        d->extraData->objectName.setValueBypassingBindings(name);
        d->extraData->objectName.notify(); // also emits a signal
    }
}
 
QBindable<QString> QObject::bindableObjectName()
{
    Q_D(QObject);
 
    if (!d->extraData)
        d->extraData = new QObjectPrivate::ExtraData(d);
 
    return QBindable<QString>(&d->extraData->objectName);
}
 
bool QObject::event(QEvent *e)
{
    switch (e->type()) {
    case QEvent::Timer:
        timerEvent((QTimerEvent *)e);
        break;
 
    case QEvent::ChildAdded:
    case QEvent::ChildPolished:
    case QEvent::ChildRemoved:
        childEvent((QChildEvent *)e);
        break;
 
    case QEvent::DeferredDelete:
        qDeleteInEventHandler(this);
        break;
 
    case QEvent::MetaCall:
        {
            QAbstractMetaCallEvent *mce = static_cast<QAbstractMetaCallEvent*>(e);
 
            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;
        }
 
    case QEvent::ThreadChange: {
        Q_D(QObject);
        QThreadData *threadData = d->threadData.loadRelaxed();
        QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher.loadRelaxed();
        if (eventDispatcher) {
            QList<QAbstractEventDispatcher::TimerInfo> timers = eventDispatcher->registeredTimers(this);
            if (!timers.isEmpty()) {
                // do not to release our timer ids back to the pool (since the timer ids are moving to a new thread).
                eventDispatcher->unregisterTimers(this);
                QMetaObject::invokeMethod(this, "_q_reregisterTimers", Qt::QueuedConnection,
                                          Q_ARG(void*, (new QList<QAbstractEventDispatcher::TimerInfo>(timers))));
            }
        }
        break;
    }
 
    default:
        if (e->type() >= QEvent::User) {
            customEvent(e);
            break;
        }
        return false;
    }
    return true;
}
 
void QObject::timerEvent(QTimerEvent *)
{
}
 
 
void QObject::childEvent(QChildEvent * /* event */)
{
}
 
 
void QObject::customEvent(QEvent * /* event */)
{
}
 
 
 
bool QObject::eventFilter(QObject * /* watched */, QEvent * /* event */)
{
    return false;
}
 
bool QObject::blockSignals(bool block) noexcept
{
    Q_D(QObject);
    bool previous = d->blockSig;
    d->blockSig = block;
    return previous;
}
 
QThread *QObject::thread() const
{
    return d_func()->threadData.loadRelaxed()->thread.loadAcquire();
}
 
void QObject::moveToThread(QThread *targetThread)
{
    Q_D(QObject);
 
    if (d->threadData.loadRelaxed()->thread.loadAcquire() == targetThread) {
        // object is already in this thread
        return;
    }
 
    if (d->parent != nullptr) {
        qWarning("QObject::moveToThread: Cannot move objects with a parent");
        return;
    }
    if (d->isWidget) {
        qWarning("QObject::moveToThread: Widgets cannot be moved to a new thread");
        return;
    }
    if (!d->bindingStorage.isEmpty()) {
        qWarning("QObject::moveToThread: Can not move objects that contain bindings or are used in bindings to a new thread.");
        return;
    }
 
    QThreadData *currentData = QThreadData::current();
    QThreadData *targetData = targetThread ? QThreadData::get2(targetThread) : nullptr;
    QThreadData *thisThreadData = d->threadData.loadAcquire();
    if (!thisThreadData->thread.loadRelaxed() && currentData == targetData) {
        // one exception to the rule: we allow moving objects with no thread affinity to the current thread
        currentData = thisThreadData;
    } else if (thisThreadData != currentData) {
        qWarning("QObject::moveToThread: Current thread (%p) is not the object's thread (%p).\n"
                 "Cannot move to target thread (%p)\n",
                 currentData->thread.loadRelaxed(), thisThreadData->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. "
                 "Check that all plugins are compiled against the right Qt binaries. Export "
                 "DYLD_PRINT_LIBRARIES=1 and check that only one set of binaries are being loaded.");
#endif
 
        return;
    }
 
    // prepare to move
    d->moveToThread_helper();
 
    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(&currentData->postEventList.mutex,
                               &targetData->postEventList.mutex);
 
    // keep currentData alive (since we've got it locked)
    currentData->ref();
 
    // move the object
    d_func()->setThreadData_helper(currentData, targetData);
 
    locker.unlock();
 
    // now currentData can commit suicide if it wants to
    currentData->deref();
}
 
void QObjectPrivate::moveToThread_helper()
{
    Q_Q(QObject);
    QEvent e(QEvent::ThreadChange);
    QCoreApplication::sendEvent(q, &e);
    for (int i = 0; i < children.size(); ++i) {
        QObject *child = children.at(i);
        child->d_func()->moveToThread_helper();
    }
}
 
void QObjectPrivate::setThreadData_helper(QThreadData *currentData, QThreadData *targetData)
{
    Q_Q(QObject);
 
    // move posted events
    int eventsMoved = 0;
    for (int i = 0; i < currentData->postEventList.size(); ++i) {
        const QPostEvent &pe = currentData->postEventList.at(i);
        if (!pe.event)
            continue;
        if (pe.receiver == q) {
            // move this post event to the targetList
            targetData->postEventList.addEvent(pe);
            const_cast<QPostEvent &>(pe).event = nullptr;
            ++eventsMoved;
        }
    }
    if (eventsMoved > 0 && targetData->hasEventDispatcher()) {
        targetData->canWait = false;
        targetData->eventDispatcher.loadRelaxed()->wakeUp();
    }
 
    // the current emitting thread shouldn't restore currentSender after calling moveToThread()
    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();
    threadData.loadRelaxed()->deref();
 
    // synchronizes with loadAcquire e.g. in QCoreApplication::postEvent
    threadData.storeRelease(targetData);
 
    for (int i = 0; i < children.size(); ++i) {
        QObject *child = children.at(i);
        child->d_func()->setThreadData_helper(currentData, targetData);
    }
}
 
void QObjectPrivate::_q_reregisterTimers(void *pointer)
{
    Q_Q(QObject);
    QList<QAbstractEventDispatcher::TimerInfo> *timerList = reinterpret_cast<QList<QAbstractEventDispatcher::TimerInfo> *>(pointer);
    QAbstractEventDispatcher *eventDispatcher = threadData.loadRelaxed()->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);
    }
    delete timerList;
}
 
 
//
// The timer flag hasTimer is set when startTimer is called.
// It is not reset when killing the timer because more than
// one timer might be active.
//
 
int QObject::startTimer(int interval, Qt::TimerType timerType)
{
    Q_D(QObject);
 
    if (Q_UNLIKELY(interval < 0)) {
        qWarning("QObject::startTimer: Timers cannot have negative intervals");
        return 0;
    }
 
    auto thisThreadData = d->threadData.loadRelaxed();
    if (Q_UNLIKELY(!thisThreadData->hasEventDispatcher())) {
        qWarning("QObject::startTimer: Timers can only be used with threads started with QThread");
        return 0;
    }
    if (Q_UNLIKELY(thread() != QThread::currentThread())) {
        qWarning("QObject::startTimer: Timers cannot be started from another thread");
        return 0;
    }
    int timerId = thisThreadData->eventDispatcher.loadRelaxed()->registerTimer(interval, timerType, this);
    if (!d->extraData)
        d->extraData = new QObjectPrivate::ExtraData(d);
    d->extraData->runningTimers.append(timerId);
    return timerId;
}
 
void QObject::killTimer(int id)
{
    Q_D(QObject);
    if (Q_UNLIKELY(thread() != QThread::currentThread())) {
        qWarning("QObject::killTimer: Timers cannot be stopped from another thread");
        return;
    }
    if (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, %ls), timer has not been killed",
                     id,
                     this,
                     metaObject()->className(),
                     qUtf16Printable(objectName()));
            return;
        }
 
        auto thisThreadData = d->threadData.loadRelaxed();
        if (thisThreadData->hasEventDispatcher())
            thisThreadData->eventDispatcher.loadRelaxed()->unregisterTimer(id);
 
        d->extraData->runningTimers.remove(at);
        QAbstractEventDispatcherPrivate::releaseTimerId(id);
    }
}
 
 
static void qt_qFindChildren_with_name(const QObject *parent, const QString &name,
                                       const QMetaObject &mo, QList<void *> *list,
                                       Qt::FindChildOptions options)
{
    Q_ASSERT(parent);
    Q_ASSERT(list);
    Q_ASSERT(!name.isNull());
    for (QObject *obj : parent->children()) {
        if (mo.cast(obj) && obj->objectName() == name)
            list->append(obj);
        if (options & Qt::FindChildrenRecursively)
            qt_qFindChildren_with_name(obj, name, mo, list, options);
    }
}
 
void qt_qFindChildren_helper(const QObject *parent, const QString &name,
                             const QMetaObject &mo, QList<void*> *list, Qt::FindChildOptions options)
{
    if (name.isNull())
        return qt_qFindChildren_helper(parent, mo, list, options);
    else
        return qt_qFindChildren_with_name(parent, name, mo, list, options);
}
 
void qt_qFindChildren_helper(const QObject *parent, const QMetaObject &mo,
                             QList<void*> *list, Qt::FindChildOptions options)
{
    Q_ASSERT(parent);
    Q_ASSERT(list);
    for (QObject *obj : parent->children()) {
        if (mo.cast(obj))
            list->append(obj);
        if (options & Qt::FindChildrenRecursively)
            qt_qFindChildren_helper(obj, mo, list, options);
    }
}
 
#if QT_CONFIG(regularexpression)
void qt_qFindChildren_helper(const QObject *parent, const QRegularExpression &re,
                             const QMetaObject &mo, QList<void*> *list, Qt::FindChildOptions options)
{
    Q_ASSERT(parent);
    Q_ASSERT(list);
    for (QObject *obj : parent->children()) {
        if (mo.cast(obj)) {
            QRegularExpressionMatch m = re.match(obj->objectName());
            if (m.hasMatch())
                list->append(obj);
        }
        if (options & Qt::FindChildrenRecursively)
            qt_qFindChildren_helper(obj, re, mo, list, options);
    }
}
#endif // QT_CONFIG(regularexpression)
 
QObject *qt_qFindChild_helper(const QObject *parent, const QString &name, const QMetaObject &mo, Qt::FindChildOptions options)
{
    Q_ASSERT(parent);
    for (QObject *obj : parent->children()) {
        if (mo.cast(obj) && (name.isNull() || obj->objectName() == name))
            return obj;
    }
    if (options & Qt::FindChildrenRecursively) {
        for (QObject *child : parent->children()) {
            if (QObject *obj = qt_qFindChild_helper(child, name, mo, options))
                return obj;
        }
    }
    return nullptr;
}
 
void QObject::setParent(QObject *parent)
{
    Q_D(QObject);
    Q_ASSERT(!d->isWidget);
    d->setParent_helper(parent);
}
 
void QObjectPrivate::deleteChildren()
{
    Q_ASSERT_X(!isDeletingChildren, "QObjectPrivate::deleteChildren()", "isDeletingChildren already set, did this function recurse?");
    isDeletingChildren = true;
    // delete children objects
    // don't use qDeleteAll as the destructor of the child might
    // delete siblings
    for (int i = 0; i < children.count(); ++i) {
        currentChildBeingDeleted = children.at(i);
        children[i] = nullptr;
        delete currentChildBeingDeleted;
    }
    children.clear();
    currentChildBeingDeleted = nullptr;
    isDeletingChildren = false;
}
 
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
            && parentD->currentChildBeingDeleted == q) {
            // don't do anything since QObjectPrivate::deleteChildren() already
            // cleared our entry in parentD->children.
        } else {
            const int index = parentD->children.indexOf(q);
            if (index < 0) {
                // we're probably recursing into setParent() from a ChildRemoved event, don't do anything
            } else if (parentD->isDeletingChildren) {
                parentD->children[index] = nullptr;
            } else {
                parentD->children.removeAt(index);
                if (sendChildEvents && parentD->receiveChildEvents) {
                    QChildEvent e(QEvent::ChildRemoved, q);
                    QCoreApplication::sendEvent(parent, &e);
                }
            }
        }
    }
    parent = o;
    if (parent) {
        // object hierarchies are constrained to a single thread
        if (threadData.loadRelaxed() != parent->d_func()->threadData.loadRelaxed()) {
            qWarning("QObject::setParent: Cannot set parent, new parent is in a different thread");
            parent = nullptr;
            return;
        }
        parent->d_func()->children.append(q);
        if (sendChildEvents && parent->d_func()->receiveChildEvents) {
            if (!isWidget) {
                QChildEvent e(QEvent::ChildAdded, q);
                QCoreApplication::sendEvent(parent, &e);
            }
        }
    }
}
 
void QObject::installEventFilter(QObject *obj)
{
    Q_D(QObject);
    if (!obj)
        return;
    if (d->threadData.loadRelaxed() != obj->d_func()->threadData.loadRelaxed()) {
        qWarning("QObject::installEventFilter(): Cannot filter events for objects in a different thread.");
        return;
    }
 
    if (!d->extraData)
        d->extraData = new QObjectPrivate::ExtraData(d);
 
    // clean up unused items in the list
    d->extraData->eventFilters.removeAll((QObject *)nullptr);
    d->extraData->eventFilters.removeAll(obj);
    d->extraData->eventFilters.prepend(obj);
}
 
void QObject::removeEventFilter(QObject *obj)
{
    Q_D(QObject);
    if (d->extraData) {
        for (int i = 0; i < d->extraData->eventFilters.count(); ++i) {
            if (d->extraData->eventFilters.at(i) == obj)
                d->extraData->eventFilters[i] = nullptr;
        }
    }
}
 
void QObject::deleteLater()
{
#ifdef QT_DEBUG
    if (qApp == this)
        qWarning("You are deferring the delete of QCoreApplication, this may not work as expected.");
#endif
    QCoreApplication::postEvent(this, new QDeferredDeleteEvent());
}
 
/*****************************************************************************
  Signals and slots
 *****************************************************************************/
 
const char *qFlagLocation(const char *method)
{
    QThreadData *currentThreadData = QThreadData::current(false);
    if (currentThreadData != nullptr)
        currentThreadData->flaggedSignatures.store(method);
    return method;
}
 
static int extract_code(const char *member)
{
    // extract code, ensure QMETHOD_CODE <= code <= QSIGNAL_CODE
    return (((int)(*member) - '0') & 0x3);
}
 
static const char *extract_location(const char *member)
{
    if (QThreadData::current()->flaggedSignatures.contains(member)) {
        // signature includes location information after the first null-terminator
        const char *location = member + qstrlen(member) + 1;
        if (*location != '\0')
            return location;
    }
    return nullptr;
}
 
static bool check_signal_macro(const QObject *sender, const char *signal,
                                const char *func, const char *op)
{
    int sigcode = extract_code(signal);
    if (sigcode != QSIGNAL_CODE) {
        if (sigcode == QSLOT_CODE)
            qCWarning(lcConnect, "QObject::%s: Attempt to %s non-signal %s::%s", func, op,
                      sender->metaObject()->className(), signal + 1);
        else
            qCWarning(lcConnect, "QObject::%s: Use the SIGNAL macro to %s %s::%s", func, op,
                      sender->metaObject()->className(), signal);
        return false;
    }
    return true;
}
 
static bool check_method_code(int code, const QObject *object, const char *method, const char *func)
{
    if (code != QSLOT_CODE && code != QSIGNAL_CODE) {
        qCWarning(lcConnect,
                  "QObject::%s: Use the SLOT or SIGNAL macro to "
                  "%s %s::%s",
                  func, func, object->metaObject()->className(), method);
        return false;
    }
    return true;
}
 
Q_DECL_COLD_FUNCTION
static void err_method_notfound(const QObject *object,
                                const char *method, const char *func)
{
    const char *type = "method";
    switch (extract_code(method)) {
        case QSLOT_CODE:   type = "slot";   break;
        case QSIGNAL_CODE: type = "signal"; break;
    }
    const char *loc = extract_location(method);
    if (strchr(method, ')') == nullptr) // common typing mistake
        qCWarning(lcConnect, "QObject::%s: Parentheses expected, %s %s::%s%s%s", func, type,
                  object->metaObject()->className(), method + 1, loc ? " in " : "", loc ? loc : "");
    else
        qCWarning(lcConnect, "QObject::%s: No such %s %s::%s%s%s", func, type,
                  object->metaObject()->className(), method + 1, loc ? " in " : "", loc ? loc : "");
}
 
Q_DECL_COLD_FUNCTION
static void err_info_about_objects(const char *func, const QObject *sender, const QObject *receiver)
{
    QString a = sender ? sender->objectName() : QString();
    QString b = receiver ? receiver->objectName() : QString();
    if (!a.isEmpty())
        qCWarning(lcConnect, "QObject::%s:  (sender name:   '%s')", func, a.toLocal8Bit().data());
    if (!b.isEmpty())
        qCWarning(lcConnect, "QObject::%s:  (receiver name: '%s')", func, b.toLocal8Bit().data());
}
 
QObject *QObject::sender() const
{
    Q_D(const QObject);
 
    QBasicMutexLocker locker(signalSlotLock(this));
    QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed();
    if (!cd || !cd->currentSender)
        return nullptr;
 
    for (QObjectPrivate::Connection *c = cd->senders; c; c = c->next) {
        if (c->sender == cd->currentSender->sender)
            return cd->currentSender->sender;
    }
 
    return nullptr;
}
 
int QObject::senderSignalIndex() const
{
    Q_D(const QObject);
 
    QBasicMutexLocker locker(signalSlotLock(this));
    QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed();
    if (!cd || !cd->currentSender)
        return -1;
 
    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(), cd->currentSender->signal).methodIndex();
        }
    }
 
    return -1;
}
 
int QObject::receivers(const char *signal) const
{
    Q_D(const QObject);
    int receivers = 0;
    if (signal) {
        QByteArray signal_name = QMetaObject::normalizedSignature(signal);
        signal = signal_name;
#ifndef QT_NO_DEBUG
        if (!check_signal_macro(this, signal, "receivers", "bind"))
            return 0;
#endif
        signal++; // skip code
        int signal_index = d->signalIndex(signal);
        if (signal_index < 0) {
#ifndef QT_NO_DEBUG
            err_method_notfound(this, signal - 1, "receivers");
#endif
            return 0;
        }
 
        if (!d->isSignalConnected(signal_index))
            return receivers;
 
        if (d->declarativeData && QAbstractDeclarativeData::receivers) {
            receivers += QAbstractDeclarativeData::receivers(d->declarativeData, this,
                                                             signal_index);
        }
 
        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();
            }
        }
    }
    return receivers;
}
 
bool QObject::isSignalConnected(const QMetaMethod &signal) const
{
    Q_D(const QObject);
    if (!signal.mobj)
        return false;
 
    Q_ASSERT_X(signal.mobj->cast(this) && signal.methodType() == QMetaMethod::Signal,
               "QObject::isSignalConnected" , "the parameter must be a signal member of the object");
    uint signalIndex = signal.relativeMethodIndex();
 
    if (signal.data.flags() & MethodCloned)
        signalIndex = QMetaObjectPrivate::originalClone(signal.mobj, signalIndex);
 
    signalIndex += QMetaObjectPrivate::signalOffset(signal.mobj);
 
    QBasicMutexLocker locker(signalSlotLock(this));
    return d->isSignalConnected(signalIndex, true);
}
 
void QMetaObjectPrivate::memberIndexes(const QObject *obj,
                                       const QMetaMethod &member,
                                       int *signalIndex, int *methodIndex)
{
    *signalIndex = -1;
    *methodIndex = -1;
    if (!obj || !member.mobj)
        return;
    const QMetaObject *m = obj->metaObject();
    // Check that member is member of obj class
    while (m != nullptr && m != member.mobj)
        m = m->d.superdata;
    if (!m)
        return;
    *signalIndex = *methodIndex = member.relativeMethodIndex();
 
    int signalOffset;
    int methodOffset;
    computeOffsets(m, &signalOffset, &methodOffset);
 
    *methodIndex += methodOffset;
    if (member.methodType() == QMetaMethod::Signal) {
        *signalIndex = originalClone(m, *signalIndex);
        *signalIndex += signalOffset;
    } else {
        *signalIndex = -1;
    }
}
 
#ifndef QT_NO_DEBUG
static inline void check_and_warn_compat(const QMetaObject *sender, const QMetaMethod &signal,
                                         const QMetaObject *receiver, const QMetaMethod &method)
{
    if (signal.attributes() & QMetaMethod::Compatibility) {
        if (!(method.attributes() & QMetaMethod::Compatibility))
            qCWarning(lcConnect, "QObject::connect: Connecting from COMPAT signal (%s::%s)",
                      sender->className(), signal.methodSignature().constData());
    } else if ((method.attributes() & QMetaMethod::Compatibility)
               && method.methodType() == QMetaMethod::Signal) {
        qCWarning(lcConnect, "QObject::connect: Connecting from %s::%s to COMPAT slot (%s::%s)",
                  sender->className(), signal.methodSignature().constData(), receiver->className(),
                  method.methodSignature().constData());
    }
}
#endif
 
QMetaObject::Connection QObject::connect(const QObject *sender, const char *signal,
                                         const QObject *receiver, const char *method,
                                         Qt::ConnectionType type)
{
    if (sender == nullptr || receiver == nullptr || signal == nullptr || method == nullptr) {
        qCWarning(lcConnect, "QObject::connect: Cannot connect %s::%s to %s::%s",
                  sender ? sender->metaObject()->className() : "(nullptr)",
                  (signal && *signal) ? signal + 1 : "(nullptr)",
                  receiver ? receiver->metaObject()->className() : "(nullptr)",
                  (method && *method) ? method + 1 : "(nullptr)");
        return QMetaObject::Connection(nullptr);
    }
    QByteArray tmp_signal_name;
 
    if (!check_signal_macro(sender, signal, "connect", "bind"))
        return QMetaObject::Connection(nullptr);
    const QMetaObject *smeta = sender->metaObject();
    const char *signal_arg = signal;
    ++signal; // skip code
    QArgumentTypeArray signalTypes;
    Q_ASSERT(QMetaObjectPrivate::get(smeta)->revision >= 7);
    QByteArray signalName = QMetaObjectPrivate::decodeMethodSignature(signal, signalTypes);
    int signal_index = QMetaObjectPrivate::indexOfSignalRelative(
            &smeta, signalName, signalTypes.size(), signalTypes.constData());
    if (signal_index < 0) {
        // check for normalized signatures
        tmp_signal_name = QMetaObject::normalizedSignature(signal - 1);
        signal = tmp_signal_name.constData() + 1;
 
        signalTypes.clear();
        signalName = QMetaObjectPrivate::decodeMethodSignature(signal, signalTypes);
        smeta = sender->metaObject();
        signal_index = QMetaObjectPrivate::indexOfSignalRelative(
                &smeta, signalName, signalTypes.size(), signalTypes.constData());
    }
    if (signal_index < 0) {
        err_method_notfound(sender, signal_arg, "connect");
        err_info_about_objects("connect", sender, receiver);
        return QMetaObject::Connection(nullptr);
    }
    signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index);
    signal_index += QMetaObjectPrivate::signalOffset(smeta);
 
    QByteArray tmp_method_name;
    int membcode = extract_code(method);
 
    if (!check_method_code(membcode, receiver, method, "connect"))
        return QMetaObject::Connection(nullptr);
    const char *method_arg = method;
    ++method; // skip code
 
    QArgumentTypeArray methodTypes;
    QByteArray methodName = QMetaObjectPrivate::decodeMethodSignature(method, methodTypes);
    const QMetaObject *rmeta = receiver->metaObject();
    int method_index_relative = -1;
    Q_ASSERT(QMetaObjectPrivate::get(rmeta)->revision >= 7);
    switch (membcode) {
    case QSLOT_CODE:
        method_index_relative = QMetaObjectPrivate::indexOfSlotRelative(
                &rmeta, methodName, methodTypes.size(), methodTypes.constData());
        break;
    case QSIGNAL_CODE:
        method_index_relative = QMetaObjectPrivate::indexOfSignalRelative(
                &rmeta, methodName, methodTypes.size(), methodTypes.constData());
        break;
    }
    if (method_index_relative < 0) {
        // check for normalized methods
        tmp_method_name = QMetaObject::normalizedSignature(method);
        method = tmp_method_name.constData();
 
        methodTypes.clear();
        methodName = QMetaObjectPrivate::decodeMethodSignature(method, methodTypes);
        // rmeta may have been modified above
        rmeta = receiver->metaObject();
        switch (membcode) {
        case QSLOT_CODE:
            method_index_relative = QMetaObjectPrivate::indexOfSlotRelative(
                    &rmeta, methodName, methodTypes.size(), methodTypes.constData());
            break;
        case QSIGNAL_CODE:
            method_index_relative = QMetaObjectPrivate::indexOfSignalRelative(
                    &rmeta, methodName, methodTypes.size(), methodTypes.constData());
            break;
        }
    }
 
    if (method_index_relative < 0) {
        err_method_notfound(receiver, method_arg, "connect");
        err_info_about_objects("connect", sender, receiver);
        return QMetaObject::Connection(nullptr);
    }
 
    if (!QMetaObjectPrivate::checkConnectArgs(signalTypes.size(), signalTypes.constData(),
                                              methodTypes.size(), methodTypes.constData())) {
        qCWarning(lcConnect,
                  "QObject::connect: Incompatible sender/receiver arguments"
                  "\n        %s::%s --> %s::%s",
                  sender->metaObject()->className(), signal, receiver->metaObject()->className(),
                  method);
        return QMetaObject::Connection(nullptr);
    }
 
    int *types = nullptr;
    if ((type == Qt::QueuedConnection)
            && !(types = queuedConnectionTypes(signalTypes.constData(), signalTypes.size()))) {
        return QMetaObject::Connection(nullptr);
    }
 
#ifndef QT_NO_DEBUG
    QMetaMethod smethod = QMetaObjectPrivate::signal(smeta, signal_index);
    QMetaMethod rmethod = rmeta->method(method_index_relative + rmeta->methodOffset());
    check_and_warn_compat(smeta, smethod, rmeta, rmethod);
#endif
    QMetaObject::Connection handle = QMetaObject::Connection(QMetaObjectPrivate::connect(
        sender, signal_index, smeta, receiver, method_index_relative, rmeta ,type, types));
    return handle;
}
 
QMetaObject::Connection QObject::connect(const QObject *sender, const QMetaMethod &signal,
                                     const QObject *receiver, const QMetaMethod &method,
                                     Qt::ConnectionType type)
{
    if (sender == nullptr
            || receiver == nullptr
            || signal.methodType() != QMetaMethod::Signal
            || method.methodType() == QMetaMethod::Constructor) {
        qCWarning(lcConnect, "QObject::connect: Cannot connect %s::%s to %s::%s",
                  sender ? sender->metaObject()->className() : "(nullptr)",
                  signal.methodSignature().constData(),
                  receiver ? receiver->metaObject()->className() : "(nullptr)",
                  method.methodSignature().constData());
        return QMetaObject::Connection(nullptr);
    }
 
    int signal_index;
    int method_index;
    {
        int dummy;
        QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy);
        QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index);
    }
 
    const QMetaObject *smeta = sender->metaObject();
    const QMetaObject *rmeta = receiver->metaObject();
    if (signal_index == -1) {
        qCWarning(lcConnect, "QObject::connect: Can't find signal %s on instance of class %s",
                  signal.methodSignature().constData(), smeta->className());
        return QMetaObject::Connection(nullptr);
    }
    if (method_index == -1) {
        qCWarning(lcConnect, "QObject::connect: Can't find method %s on instance of class %s",
                  method.methodSignature().constData(), rmeta->className());
        return QMetaObject::Connection(nullptr);
    }
 
    if (!QMetaObject::checkConnectArgs(signal.methodSignature().constData(),
                                       method.methodSignature().constData())) {
        qCWarning(lcConnect,
                  "QObject::connect: Incompatible sender/receiver arguments"
                  "\n        %s::%s --> %s::%s",
                  smeta->className(), signal.methodSignature().constData(), rmeta->className(),
                  method.methodSignature().constData());
        return QMetaObject::Connection(nullptr);
    }
 
    int *types = nullptr;
    if ((type == Qt::QueuedConnection) && !(types = queuedConnectionTypes(signal)))
        return QMetaObject::Connection(nullptr);
 
#ifndef QT_NO_DEBUG
    check_and_warn_compat(smeta, signal, rmeta, method);
#endif
    QMetaObject::Connection handle = QMetaObject::Connection(QMetaObjectPrivate::connect(
        sender, signal_index, signal.enclosingMetaObject(), receiver, method_index, nullptr, type, types));
    return handle;
}
 
bool QObject::disconnect(const QObject *sender, const char *signal,
                         const QObject *receiver, const char *method)
{
    if (sender == nullptr || (receiver == nullptr && method != nullptr)) {
        qCWarning(lcConnect, "QObject::disconnect: Unexpected nullptr parameter");
        return false;
    }
 
    const char *signal_arg = signal;
    QByteArray signal_name;
    bool signal_found = false;
    if (signal) {
        QT_TRY {
            signal_name = QMetaObject::normalizedSignature(signal);
            signal = signal_name.constData();
        } QT_CATCH (const std::bad_alloc &) {
            // if the signal is already normalized, we can continue.
            if (sender->metaObject()->indexOfSignal(signal + 1) == -1)
                QT_RETHROW;
        }
 
        if (!check_signal_macro(sender, signal, "disconnect", "unbind"))
            return false;
        signal++; // skip code
    }
 
    QByteArray method_name;
    const char *method_arg = method;
    int membcode = -1;
    bool method_found = false;
    if (method) {
        QT_TRY {
            method_name = QMetaObject::normalizedSignature(method);
            method = method_name.constData();
        } QT_CATCH(const std::bad_alloc &) {
            // if the method is already normalized, we can continue.
            if (receiver->metaObject()->indexOfMethod(method + 1) == -1)
                QT_RETHROW;
        }
 
        membcode = extract_code(method);
        if (!check_method_code(membcode, receiver, method, "disconnect"))
            return false;
        method++; // skip code
    }
 
    /* We now iterate through all the sender's and receiver's meta
     * objects in order to also disconnect possibly shadowed signals
     * and slots with the same signature.
    */
    bool res = false;
    const QMetaObject *smeta = sender->metaObject();
    QByteArray signalName;
    QArgumentTypeArray signalTypes;
    Q_ASSERT(QMetaObjectPrivate::get(smeta)->revision >= 7);
    if (signal)
        signalName = QMetaObjectPrivate::decodeMethodSignature(signal, signalTypes);
    QByteArray methodName;
    QArgumentTypeArray methodTypes;
    Q_ASSERT(!receiver || QMetaObjectPrivate::get(receiver->metaObject())->revision >= 7);
    if (method)
        methodName = QMetaObjectPrivate::decodeMethodSignature(method, methodTypes);
    do {
        int signal_index = -1;
        if (signal) {
            signal_index = QMetaObjectPrivate::indexOfSignalRelative(
                        &smeta, signalName, signalTypes.size(), signalTypes.constData());
            if (signal_index < 0)
                break;
            signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index);
            signal_index += QMetaObjectPrivate::signalOffset(smeta);
            signal_found = true;
        }
 
        if (!method) {
            res |= QMetaObjectPrivate::disconnect(sender, signal_index, smeta, receiver, -1, nullptr);
        } else {
            const QMetaObject *rmeta = receiver->metaObject();
            do {
                int method_index = QMetaObjectPrivate::indexOfMethod(
                            rmeta, methodName, methodTypes.size(), methodTypes.constData());
                if (method_index >= 0)
                    while (method_index < rmeta->methodOffset())
                            rmeta = rmeta->superClass();
                if (method_index < 0)
                    break;
                res |= QMetaObjectPrivate::disconnect(sender, signal_index, smeta, receiver, method_index, nullptr);
                method_found = true;
            } while ((rmeta = rmeta->superClass()));
        }
    } while (signal && (smeta = smeta->superClass()));
 
    if (signal && !signal_found) {
        err_method_notfound(sender, signal_arg, "disconnect");
        err_info_about_objects("disconnect", sender, receiver);
    } else if (method && !method_found) {
        err_method_notfound(receiver, method_arg, "disconnect");
        err_info_about_objects("disconnect", sender, receiver);
    }
    if (res) {
        if (!signal)
            const_cast<QObject *>(sender)->disconnectNotify(QMetaMethod());
    }
    return res;
}
 
bool QObject::disconnect(const QObject *sender, const QMetaMethod &signal,
                         const QObject *receiver, const QMetaMethod &method)
{
    if (sender == nullptr || (receiver == nullptr && method.mobj != nullptr)) {
        qCWarning(lcConnect, "QObject::disconnect: Unexpected nullptr parameter");
        return false;
    }
    if (signal.mobj) {
        if (signal.methodType() != QMetaMethod::Signal) {
            qCWarning(lcConnect, "QObject::%s: Attempt to %s non-signal %s::%s",
                     "disconnect","unbind",
                     sender->metaObject()->className(), signal.methodSignature().constData());
            return false;
        }
    }
    if (method.mobj) {
        if (method.methodType() == QMetaMethod::Constructor) {
            qCWarning(lcConnect, "QObject::disconnect: cannot use constructor as argument %s::%s",
                      receiver->metaObject()->className(), method.methodSignature().constData());
            return false;
        }
    }
 
    int signal_index;
    int method_index;
    {
        int dummy;
        QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy);
        QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index);
    }
    // If we are here sender is not nullptr. If signal is not nullptr while signal_index
    // is -1 then this signal is not a member of sender.
    if (signal.mobj && signal_index == -1) {
        qCWarning(lcConnect, "QObject::disconnect: signal %s not found on class %s",
                  signal.methodSignature().constData(), sender->metaObject()->className());
        return false;
    }
    // If this condition is true then method is not a member of receiver.
    if (receiver && method.mobj && method_index == -1) {
        qCWarning(lcConnect, "QObject::disconnect: method %s not found on class %s",
                  method.methodSignature().constData(), receiver->metaObject()->className());
        return false;
    }
 
    if (!QMetaObjectPrivate::disconnect(sender, signal_index, signal.mobj, receiver, method_index, nullptr))
        return false;
 
    if (!signal.isValid()) {
        // The signal is a wildcard, meaning all signals were disconnected.
        // QMetaObjectPrivate::disconnect() doesn't call disconnectNotify()
        // per connection in this case. Call it once now, with an invalid
        // QMetaMethod as argument, as documented.
        const_cast<QObject *>(sender)->disconnectNotify(signal);
    }
    return true;
}
 
void QObject::connectNotify(const QMetaMethod &signal)
{
    Q_UNUSED(signal);
}
 
void QObject::disconnectNotify(const QMetaMethod &signal)
{
    Q_UNUSED(signal);
}
 
/*
    \internal
    convert a signal index from the method range to the signal range
 */
static int methodIndexToSignalIndex(const QMetaObject **base, int signal_index)
{
    if (signal_index < 0)
        return signal_index;
    const QMetaObject *metaObject = *base;
    while (metaObject && metaObject->methodOffset() > signal_index)
        metaObject = metaObject->superClass();
 
    if (metaObject) {
        int signalOffset, methodOffset;
        computeOffsets(metaObject, &signalOffset, &methodOffset);
        if (signal_index < metaObject->methodCount())
            signal_index = QMetaObjectPrivate::originalClone(metaObject, signal_index - methodOffset) + signalOffset;
        else
            signal_index = signal_index - methodOffset + signalOffset;
        *base = metaObject;
    }
    return signal_index;
}
 
QMetaObject::Connection QMetaObject::connect(const QObject *sender, int signal_index,
                                             const QObject *receiver, int method_index, int type,
                                             int *types)
{
    const QMetaObject *smeta = sender->metaObject();
    signal_index = methodIndexToSignalIndex(&smeta, signal_index);
    return Connection(QMetaObjectPrivate::connect(sender, signal_index, smeta,
                                       receiver, method_index,
                                       nullptr, //FIXME, we could speed this connection up by computing the relative index
                                       type, types));
}
 
QObjectPrivate::Connection *QMetaObjectPrivate::connect(const QObject *sender,
                                 int signal_index, const QMetaObject *smeta,
                                 const QObject *receiver, int method_index,
                                 const QMetaObject *rmeta, int type, int *types)
{
    QObject *s = const_cast<QObject *>(sender);
    QObject *r = const_cast<QObject *>(receiver);
 
    int method_offset = rmeta ? rmeta->methodOffset() : 0;
    Q_ASSERT(!rmeta || QMetaObjectPrivate::get(rmeta)->revision >= 6);
    QObjectPrivate::StaticMetaCallFunction callFunction = rmeta ? rmeta->d.static_metacall : nullptr;
 
    QOrderedMutexLocker locker(signalSlotLock(sender),
                               signalSlotLock(receiver));
 
    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.loadRelaxed() == receiver && c2->method() == method_index_absolute)
                    return nullptr;
                c2 = c2->nextConnectionList.loadRelaxed();
            }
        }
    }
    type &= ~Qt::UniqueConnection;
 
    const bool isSingleShot = type & Qt::SingleShotConnection;
    type &= ~Qt::SingleShotConnection;
 
    Q_ASSERT(type >= 0);
    Q_ASSERT(type <= 3);
 
    std::unique_ptr<QObjectPrivate::Connection> c{new QObjectPrivate::Connection};
    c->sender = s;
    c->signal_index = signal_index;
    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.storeRelaxed(types);
    c->callFunction = callFunction;
    c->isSingleShot = isSingleShot;
 
    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.release();
}
 
bool QMetaObject::disconnect(const QObject *sender, int signal_index,
                             const QObject *receiver, int method_index)
{
    const QMetaObject *smeta = sender->metaObject();
    signal_index = methodIndexToSignalIndex(&smeta, signal_index);
    return QMetaObjectPrivate::disconnect(sender, signal_index, smeta,
                                          receiver, method_index, nullptr);
}
 
bool QMetaObject::disconnectOne(const QObject *sender, int signal_index,
                                const QObject *receiver, int method_index)
{
    const QMetaObject *smeta = sender->metaObject();
    signal_index = methodIndexToSignalIndex(&smeta, signal_index);
    return QMetaObjectPrivate::disconnect(sender, signal_index, smeta,
                                          receiver, method_index, nullptr,
                                          QMetaObjectPrivate::DisconnectOne);
}
 
bool QMetaObjectPrivate::disconnectHelper(QObjectPrivate::ConnectionData *connections, int signalIndex,
                                          const QObject *receiver, int method_index, void **slot,
                                          QBasicMutex *senderMutex, DisconnectType disconnectType)
{
    bool success = false;
 
    auto &connectionList = connections->connectionsForSignal(signalIndex);
    auto *c = connectionList.first.loadRelaxed();
    while (c) {
        QObject *r = c->receiver.loadRelaxed();
        if (r && (receiver == nullptr || (r == receiver
                           && (method_index < 0 || (!c->isSlotObject && c->method() == method_index))
                           && (slot == nullptr || (c->isSlotObject && c->slotObj->compare(slot)))))) {
            bool needToUnlock = false;
            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.loadRelaxed())
                connections->removeConnection(c);
 
            if (needToUnlock)
                receiverMutex->unlock();
 
            success = true;
 
            if (disconnectType == DisconnectOne)
                return success;
        }
        c = c->nextConnectionList.loadRelaxed();
    }
    return success;
}
 
bool QMetaObjectPrivate::disconnect(const QObject *sender,
                                    int signal_index, const QMetaObject *smeta,
                                    const QObject *receiver, int method_index, void **slot,
                                    DisconnectType disconnectType)
{
    if (!sender)
        return false;
 
    QObject *s = const_cast<QObject *>(sender);
 
    QBasicMutex *senderMutex = signalSlotLock(sender);
    QBasicMutexLocker locker(senderMutex);
 
    QObjectPrivate::ConnectionData *scd = QObjectPrivate::get(s)->connections.loadRelaxed();
    if (!scd)
        return false;
 
    bool success = false;
    {
        // 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 < scd->signalVectorCount()) {
            if (disconnectHelper(connections.data(), signal_index, receiver, method_index, slot, senderMutex, disconnectType))
                success = true;
        }
    }
 
    locker.unlock();
    if (success) {
        scd->cleanOrphanedConnections(s);
 
        QMetaMethod smethod = QMetaObjectPrivate::signal(smeta, signal_index);
        if (smethod.isValid())
            s->disconnectNotify(smethod);
    }
 
    return success;
}
 
// Helpers for formatting the connect statements of connectSlotsByName()'s debug mode
static QByteArray formatConnectionSignature(const char *className, const QMetaMethod &method)
{
    const auto signature = method.methodSignature();
    Q_ASSERT(signature.endsWith(')'));
    const int openParen = signature.indexOf('(');
    const bool hasParameters = openParen >= 0 && openParen < signature.size() - 2;
    QByteArray result;
    if (hasParameters) {
        result += "qOverload<"
            + signature.mid(openParen + 1, signature.size() - openParen - 2) + ">(";
    }
    result += '&';
    result += className + QByteArrayLiteral("::") + method.name();
    if (hasParameters)
        result += ')';
    return result;
}
 
static QByteArray msgConnect(const QMetaObject *senderMo, const QByteArray &senderName,
                             const QMetaMethod &signal, const QObject *receiver, int receiverIndex)
{
    const auto receiverMo = receiver->metaObject();
    const auto slot = receiverMo->method(receiverIndex);
    QByteArray message = QByteArrayLiteral("QObject::connect(")
        + senderName + ", " + formatConnectionSignature(senderMo->className(), signal)
        + ", " + receiver->objectName().toLatin1() + ", "
        + formatConnectionSignature(receiverMo->className(), slot) + ");";
    return message;
}
 
void QMetaObject::connectSlotsByName(QObject *o)
{
    if (!o)
        return;
    const QMetaObject *mo = o->metaObject();
    Q_ASSERT(mo);
    const QObjectList list = // list of all objects to look for matching signals including...
            o->findChildren<QObject *>() // all children of 'o'...
            << o; // and the object 'o' itself
 
    // for each method/slot of o ...
    for (int i = 0; i < mo->methodCount(); ++i) {
        const QByteArray slotSignature = mo->method(i).methodSignature();
        const char *slot = slotSignature.constData();
        Q_ASSERT(slot);
 
        // ...that starts with "on_", ...
        if (slot[0] != 'o' || slot[1] != 'n' || slot[2] != '_')
            continue;
 
        // ...we check each object in our list, ...
        bool foundIt = false;
        for (int j = 0; j < list.count(); ++j) {
            const QObject *co = list.at(j);
            const QByteArray coName = co->objectName().toLatin1();
 
            // ...discarding those whose objectName is not fitting the pattern "on_<objectName>_...", ...
            if (coName.isEmpty() || qstrncmp(slot + 3, coName.constData(), coName.size()) || slot[coName.size()+3] != '_')
                continue;
 
            const char *signal = slot + coName.size() + 4; // the 'signal' part of the slot name
 
            // ...for the presence of a matching signal "on_<objectName>_<signal>".
            const QMetaObject *smeta;
            int sigIndex = co->d_func()->signalIndex(signal, &smeta);
            if (sigIndex < 0) {
                // if no exactly fitting signal (name + complete parameter type list) could be found
                // look for just any signal with the correct name and at least the slot's parameter list.
                // Note: if more than one of those signals exist, the one that gets connected is
                // chosen 'at random' (order of declaration in source file)
                QList<QByteArray> compatibleSignals;
                const QMetaObject *smo = co->metaObject();
                int sigLen = int(qstrlen(signal)) - 1; // ignore the trailing ')'
                for (int k = QMetaObjectPrivate::absoluteSignalCount(smo)-1; k >= 0; --k) {
                    const QMetaMethod method = QMetaObjectPrivate::signal(smo, k);
                    if (!qstrncmp(method.methodSignature().constData(), signal, sigLen)) {
                        smeta = method.enclosingMetaObject();
                        sigIndex = k;
                        compatibleSignals.prepend(method.methodSignature());
                    }
                }
                if (compatibleSignals.size() > 1)
                    qCWarning(lcConnectSlotsByName) << "QMetaObject::connectSlotsByName: Connecting slot" << slot
                               << "with the first of the following compatible signals:" << compatibleSignals;
            }
 
            if (sigIndex < 0)
                continue;
 
            // we connect it...
            if (Connection(QMetaObjectPrivate::connect(co, sigIndex, smeta, o, i))) {
                foundIt = true;
                qCDebug(lcConnectSlotsByName, "%s",
                        msgConnect(smeta, coName, QMetaObjectPrivate::signal(smeta, sigIndex), o,  i).constData());
                // ...and stop looking for further objects with the same name.
                // Note: the Designer will make sure each object name is unique in the above
                // 'list' but other code may create two child objects with the same name. In
                // this case one is chosen 'at random'.
                break;
            }
        }
        if (foundIt) {
            // we found our slot, now skip all overloads
            while (mo->method(i + 1).attributes() & QMetaMethod::Cloned)
                ++i;
        } else if (!(mo->method(i).attributes() & QMetaMethod::Cloned)) {
            // check if the slot has the following signature: "on_..._...(..."
            int iParen = slotSignature.indexOf('(');
            int iLastUnderscore = slotSignature.lastIndexOf('_', iParen - 1);
            if (iLastUnderscore > 3)
                qCWarning(lcConnectSlotsByName,
                          "QMetaObject::connectSlotsByName: No matching signal for %s", slot);
        }
    }
}
 
struct SlotObjectGuard {
    SlotObjectGuard() = default;
    // move would be fine, but we do not need it currently
    Q_DISABLE_COPY_MOVE(SlotObjectGuard)
    explicit SlotObjectGuard(QtPrivate::QSlotObjectBase *slotObject)
        : m_slotObject(slotObject)
    {
        if (m_slotObject)
            m_slotObject->ref();
    }
 
    QtPrivate::QSlotObjectBase const *operator->() const
    { return m_slotObject; }
 
    QtPrivate::QSlotObjectBase *operator->()
    { return m_slotObject; }
 
    ~SlotObjectGuard() {
        if (m_slotObject)
            m_slotObject->destroyIfLastRef();
    }
private:
    QtPrivate::QSlotObjectBase *m_slotObject = nullptr;
};
 
static void queued_activate(QObject *sender, int signal, QObjectPrivate::Connection *c, void **argv)
{
    const int *argumentTypes = c->argumentTypes.loadRelaxed();
    if (!argumentTypes) {
        QMetaMethod m = QMetaObjectPrivate::signal(sender->metaObject(), signal);
        argumentTypes = queuedConnectionTypes(m);
        if (!argumentTypes) // cannot queue arguments
            argumentTypes = &DIRECT_CONNECTION_ONLY;
        if (!c->argumentTypes.testAndSetOrdered(nullptr, argumentTypes)) {
            if (argumentTypes != &DIRECT_CONNECTION_ONLY)
                delete[] argumentTypes;
            argumentTypes = c->argumentTypes.loadRelaxed();
        }
    }
    if (argumentTypes == &DIRECT_CONNECTION_ONLY) // cannot activate
        return;
    int nargs = 1; // include return type
    while (argumentTypes[nargs - 1])
        ++nargs;
 
    QBasicMutexLocker locker(signalSlotLock(c->receiver.loadRelaxed()));
    QObject *receiver = c->receiver.loadRelaxed();
    if (!receiver) {
        // the connection has been disconnected before we got the lock
        return;
    }
 
    SlotObjectGuard slotObjectGuard { c->isSlotObject ? c->slotObj : nullptr };
    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();
    QMetaType *types = ev->types();
 
    types[0] = QMetaType(); // return type
    args[0] = nullptr; // return value
 
    if (nargs > 1) {
        for (int n = 1; n < nargs; ++n)
            types[n] = QMetaType(argumentTypes[n - 1]);
 
        for (int n = 1; n < nargs; ++n)
            args[n] = types[n].create(argv[n]);
    }
 
    if (c->isSingleShot && !QObjectPrivate::disconnect(c)) {
        delete ev;
        return;
    }
 
    locker.relock();
    if (!c->isSingleShot && !c->receiver.loadRelaxed()) {
        // the connection has been disconnected while we were unlocked
        locker.unlock();
        delete ev;
        return;
    }
 
    QCoreApplication::postEvent(receiver, ev);
}
 
template <bool callbacks_enabled>
void doActivate(QObject *sender, int signal_index, void **argv)
{
    QObjectPrivate *sp = QObjectPrivate::get(sender);
 
    if (sp->blockSig)
        return;
 
    Q_TRACE_SCOPE(QMetaObject_activate, sender, signal_index);
 
    if (sp->isDeclarativeSignalConnected(signal_index)
            && QAbstractDeclarativeData::signalEmitted) {
        Q_TRACE_SCOPE(QMetaObject_activate_declarative_signal, sender, signal_index);
        QAbstractDeclarativeData::signalEmitted(sp->declarativeData, sender,
                                                signal_index, argv);
    }
 
    const QSignalSpyCallbackSet *signal_spy_set = callbacks_enabled ? qt_signal_spy_callback_set.loadAcquire() : nullptr;
 
    void *empty_argv[] = { nullptr };
    if (!argv)
        argv = empty_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;
    }
 
    if (callbacks_enabled && signal_spy_set->signal_begin_callback != nullptr)
        signal_spy_set->signal_begin_callback(sender, signal_index, argv);
 
    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 < signalVector->count())
        list = &signalVector->at(signal_index);
    else
        list = &signalVector->at(-1);
 
    Qt::HANDLE currentThreadId = QThread::currentThreadId();
    bool inSenderThread = currentThreadId == QObjectPrivate::get(sender)->threadData.loadRelaxed()->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.loadRelaxed();
        if (!c)
            continue;
 
        do {
            QObject * const receiver = c->receiver.loadRelaxed();
            if (!receiver)
                continue;
 
            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);
                continue;
#if QT_CONFIG(thread)
            } else if (c->connectionType == Qt::BlockingQueuedConnection) {
                if (receiverInSameThread) {
                    qWarning("Qt: Dead lock detected while activating a BlockingQueuedConnection: "
                    "Sender is %s(%p), receiver is %s(%p)",
                    sender->metaObject()->className(), sender,
                    receiver->metaObject()->className(), receiver);
                }
 
                if (c->isSingleShot && !QObjectPrivate::disconnect(c))
                    continue;
 
                QSemaphore semaphore;
                {
                    QBasicMutexLocker locker(signalSlotLock(receiver));
                    if (!c->isSingleShot && !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();
                continue;
#endif
            }
 
            if (c->isSingleShot && !QObjectPrivate::disconnect(c))
                continue;
 
            QObjectPrivate::Sender senderData(receiverInSameThread ? receiver : nullptr, sender, signal_index);
 
            if (c->isSlotObject) {
                SlotObjectGuard obj{c->slotObj};
 
                {
                    Q_TRACE_SCOPE(QMetaObject_activate_slot_functor, c->slotObj);
                    obj->call(receiver, argv);
                }
            } 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 method_relative = c->method_relative;
                const auto callFunction = c->callFunction;
                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 (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;
 
                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);
                    QMetaObject::metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv);
                }
 
                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);
 
    } while (list != &signalVector->at(-1) &&
        //start over for all signals;
        ((list = &signalVector->at(-1)), true));
 
        if (connections->currentConnectionId.loadRelaxed() == 0)
            senderDeleted = true;
    }
    if (!senderDeleted) {
        sp->connections.loadRelaxed()->cleanOrphanedConnections(sender);
 
        if (callbacks_enabled && signal_spy_set->signal_end_callback != nullptr)
            signal_spy_set->signal_end_callback(sender, signal_index);
    }
}
 
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);
}
 
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);
}
 
void QMetaObject::activate(QObject *sender, int signal_index, void **argv)
{
    const QMetaObject *mo = sender->metaObject();
    while (mo->methodOffset() > signal_index)
        mo = mo->superClass();
    activate(sender, mo, signal_index - mo->methodOffset(), argv);
}
 
int QObjectPrivate::signalIndex(const char *signalName,
                                const QMetaObject **meta) const
{
    Q_Q(const QObject);
    const QMetaObject *base = q->metaObject();
    Q_ASSERT(QMetaObjectPrivate::get(base)->revision >= 7);
    QArgumentTypeArray types;
    QByteArray name = QMetaObjectPrivate::decodeMethodSignature(signalName, types);
    int relative_index = QMetaObjectPrivate::indexOfSignalRelative(
            &base, name, types.size(), types.constData());
    if (relative_index < 0)
        return relative_index;
    relative_index = QMetaObjectPrivate::originalClone(base, relative_index);
    if (meta)
        *meta = base;
    return relative_index + QMetaObjectPrivate::signalOffset(base);
}
 
/*****************************************************************************
  Properties
 *****************************************************************************/
 
#ifndef QT_NO_PROPERTIES
 
bool QObject::setProperty(const char *name, const QVariant &value)
{
    Q_D(QObject);
    const QMetaObject *meta = metaObject();
    if (!name || !meta)
        return false;
 
    int id = meta->indexOfProperty(name);
    if (id < 0) {
        if (!d->extraData)
            d->extraData = new QObjectPrivate::ExtraData(d);
 
        const int idx = d->extraData->propertyNames.indexOf(name);
 
        if (!value.isValid()) {
            if (idx == -1)
                return false;
            d->extraData->propertyNames.removeAt(idx);
            d->extraData->propertyValues.removeAt(idx);
        } else {
            if (idx == -1) {
                d->extraData->propertyNames.append(name);
                d->extraData->propertyValues.append(value);
            } else {
                if (value.userType() == d->extraData->propertyValues.at(idx).userType()
                        && value == d->extraData->propertyValues.at(idx))
                    return false;
                d->extraData->propertyValues[idx] = value;
            }
        }
 
        QDynamicPropertyChangeEvent ev(name);
        QCoreApplication::sendEvent(this, &ev);
 
        return false;
    }
    QMetaProperty p = meta->property(id);
#ifndef QT_NO_DEBUG
    if (!p.isWritable())
        qWarning("%s::setProperty: Property \"%s\" invalid,"
                 " read-only or does not exist", metaObject()->className(), name);
#endif
    return p.write(this, value);
}
 
QVariant QObject::property(const char *name) const
{
    Q_D(const QObject);
    const QMetaObject *meta = metaObject();
    if (!name || !meta)
        return QVariant();
 
    int id = meta->indexOfProperty(name);
    if (id < 0) {
        if (!d->extraData)
            return QVariant();
        const int i = d->extraData->propertyNames.indexOf(name);
        return d->extraData->propertyValues.value(i);
    }
    QMetaProperty p = meta->property(id);
#ifndef QT_NO_DEBUG
    if (!p.isReadable())
        qWarning("%s::property: Property \"%s\" invalid or does not exist",
                 metaObject()->className(), name);
#endif
    return p.read(this);
}
 
QList<QByteArray> QObject::dynamicPropertyNames() const
{
    Q_D(const QObject);
    if (d->extraData)
        return d->extraData->propertyNames;
    return QList<QByteArray>();
}
 
#endif // QT_NO_PROPERTIES
 
 
/*****************************************************************************
  QObject debugging output routines.
 *****************************************************************************/
 
static void dumpRecursive(int level, const QObject *object)
{
    if (object) {
        const int indent = level * 4;
        const QString name = object->objectName();
        QString flags;
#if 0
        if (qApp->focusWidget() == object)
            flags += 'F';
        if (object->isWidgetType()) {
            QWidget * w = (QWidget *)object;
            if (w->isVisible()) {
                QString t("<%1,%2,%3,%4>");
                flags += t.arg(w->x()).arg(w->y()).arg(w->width()).arg(w->height());
            } else {
                flags += 'I';
            }
        }
#endif
        qDebug("%*s%s::%ls %ls", indent, "", object->metaObject()->className(),
               qUtf16Printable(name), qUtf16Printable(flags));
        for (auto child : object->children())
            dumpRecursive(level + 1, child);
    }
}
 
 
void QObject::dumpObjectTree() const
{
    dumpRecursive(0, this);
}
 
void QObject::dumpObjectInfo() const
{
    qDebug("OBJECT %s::%s", metaObject()->className(),
           objectName().isEmpty() ? "unnamed" : objectName().toLocal8Bit().data());
 
    Q_D(const QObject);
    QBasicMutexLocker locker(signalSlotLock(this));
 
    // first, look for connections where this object is the sender
    qDebug("  SIGNALS OUT");
 
    QObjectPrivate::ConnectionData *cd = d->connections.loadRelaxed();
    if (cd && cd->signalVectorCount() > 0) {
        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
            while (c) {
                if (!c->receiver.loadRelaxed()) {
                    qDebug("          <Disconnected receiver>");
                    c = c->nextConnectionList.loadRelaxed();
                    continue;
                }
                if (c->isSlotObject) {
                    qDebug("          <functor or function pointer>");
                    c = c->nextConnectionList.loadRelaxed();
                    continue;
                }
                const QMetaObject *receiverMetaObject = c->receiver.loadRelaxed()->metaObject();
                const QMetaMethod method = receiverMetaObject->method(c->method());
                qDebug("          --> %s::%s %s",
                       receiverMetaObject->className(),
                       c->receiver.loadRelaxed()->objectName().isEmpty() ? "unnamed" : qPrintable(c->receiver.loadRelaxed()->objectName()),
                       method.methodSignature().constData());
                c = c->nextConnectionList.loadRelaxed();
            }
        }
    } else {
        qDebug( "        <None>" );
    }
 
    // now look for connections where this object is the receiver
    qDebug("  SIGNALS IN");
 
    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());
                slotName = slot.methodSignature();
            }
            qDebug("          <-- %s::%s %s",
                   s->sender->metaObject()->className(),
                   s->sender->objectName().isEmpty() ? "unnamed" : qPrintable(s->sender->objectName()),
                   slotName.constData());
        }
    } else {
        qDebug("        <None>");
    }
}
 
 
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, const QObject *o)
{
    QDebugStateSaver saver(dbg);
    if (!o)
        return dbg << "QObject(0x0)";
    dbg.nospace() << o->metaObject()->className() << '(' << (const void *)o;
    if (!o->objectName().isEmpty())
        dbg << ", name = " << o->objectName();
    dbg << ')';
    return dbg;
}
#endif
 
void qDeleteInEventHandler(QObject *o)
{
    delete o;
}
 
QMetaObject::Connection QObject::connectImpl(const QObject *sender, void **signal,
                                             const QObject *receiver, void **slot,
                                             QtPrivate::QSlotObjectBase *slotObj, Qt::ConnectionType type,
                                             const int *types, const QMetaObject *senderMetaObject)
{
    if (!signal) {
        qCWarning(lcConnect, "QObject::connect: invalid nullptr parameter");
        if (slotObj)
            slotObj->destroyIfLastRef();
        return QMetaObject::Connection();
    }
 
    int signal_index = -1;
    void *args[] = { &signal_index, signal };
    for (; senderMetaObject && signal_index < 0; senderMetaObject = senderMetaObject->superClass()) {
        senderMetaObject->static_metacall(QMetaObject::IndexOfMethod, 0, args);
        if (signal_index >= 0 && signal_index < QMetaObjectPrivate::get(senderMetaObject)->signalCount)
            break;
    }
    if (!senderMetaObject) {
        qCWarning(lcConnect, "QObject::connect: signal not found in %s", sender->metaObject()->className());
        slotObj->destroyIfLastRef();
        return QMetaObject::Connection(nullptr);
    }
    signal_index += QMetaObjectPrivate::signalOffset(senderMetaObject);
    return QObjectPrivate::connectImpl(sender, signal_index, receiver, slot, slotObj, type, types, senderMetaObject);
}
 
static void connectWarning(const QObject *sender,
                           const QMetaObject *senderMetaObject,
                           const QObject *receiver,
                           const char *message)
{
    const char *senderString = sender ? sender->metaObject()->className()
                                      : senderMetaObject ? senderMetaObject->className()
                                      : "Unknown";
    const char *receiverString = receiver ? receiver->metaObject()->className()
                                          : "Unknown";
    qCWarning(lcConnect, "QObject::connect(%s, %s): %s", senderString, receiverString, message);
}
 
QMetaObject::Connection QObjectPrivate::connectImpl(const QObject *sender, int signal_index,
                                             const QObject *receiver, void **slot,
                                             QtPrivate::QSlotObjectBase *slotObj, int type,
                                             const int *types, const QMetaObject *senderMetaObject)
{
    auto connectFailureGuard = qScopeGuard([&]()
    {
        if (slotObj)
            slotObj->destroyIfLastRef();
    });
 
    if (!sender || !receiver || !slotObj || !senderMetaObject) {
        connectWarning(sender, senderMetaObject, receiver, "invalid nullptr parameter");
        return QMetaObject::Connection();
    }
 
    if (type & Qt::UniqueConnection && !slot) {
        connectWarning(sender, senderMetaObject, receiver, "unique connections require a pointer to member function of a QObject subclass");
        return QMetaObject::Connection();
    }
 
    connectFailureGuard.dismiss();
 
    QObject *s = const_cast<QObject *>(sender);
    QObject *r = const_cast<QObject *>(receiver);
 
    QOrderedMutexLocker locker(signalSlotLock(sender),
                               signalSlotLock(receiver));
 
    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.loadRelaxed() == receiver && c2->isSlotObject && c2->slotObj->compare(slot)) {
                    slotObj->destroyIfLastRef();
                    return QMetaObject::Connection();
                }
                c2 = c2->nextConnectionList.loadRelaxed();
            }
        }
    }
    type &= ~Qt::UniqueConnection;
 
    const bool isSingleShot = type & Qt::SingleShotConnection;
    type &= ~Qt::SingleShotConnection;
 
    Q_ASSERT(type >= 0);
    Q_ASSERT(type <= 3);
 
    std::unique_ptr<QObjectPrivate::Connection> c{new QObjectPrivate::Connection};
    c->sender = s;
    c->signal_index = signal_index;
    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.storeRelaxed(types);
        c->ownArgumentTypes = false;
    }
    c->isSingleShot = isSingleShot;
 
    QObjectPrivate::get(s)->addConnection(signal_index, c.get());
    QMetaObject::Connection ret(c.release());
    locker.unlock();
 
    QMetaMethod method = QMetaObjectPrivate::signal(senderMetaObject, signal_index);
    Q_ASSERT(method.isValid());
    s->connectNotify(method);
 
    return ret;
}
 
bool QObject::disconnect(const QMetaObject::Connection &connection)
{
    QObjectPrivate::Connection *c = static_cast<QObjectPrivate::Connection *>(connection.d_ptr);
    if (!c)
        return false;
    const bool disconnected = QObjectPrivate::disconnect(c);
    const_cast<QMetaObject::Connection &>(connection).d_ptr = nullptr;
    c->deref(); // has been removed from the QMetaObject::Connection object
    return disconnected;
}
 
bool QObject::disconnectImpl(const QObject *sender, void **signal, const QObject *receiver, void **slot, const QMetaObject *senderMetaObject)
{
    if (sender == nullptr || (receiver == nullptr && slot != nullptr)) {
        qCWarning(lcConnect, "QObject::disconnect: Unexpected nullptr parameter");
        return false;
    }
 
    int signal_index = -1;
    if (signal) {
        void *args[] = { &signal_index, signal };
        for (; senderMetaObject && signal_index < 0; senderMetaObject = senderMetaObject->superClass()) {
            senderMetaObject->static_metacall(QMetaObject::IndexOfMethod, 0, args);
            if (signal_index >= 0 && signal_index < QMetaObjectPrivate::get(senderMetaObject)->signalCount)
                break;
        }
        if (!senderMetaObject) {
            qCWarning(lcConnect, "QObject::disconnect: signal not found in %s", sender->metaObject()->className());
            return false;
        }
        signal_index += QMetaObjectPrivate::signalOffset(senderMetaObject);
    }
 
    return QMetaObjectPrivate::disconnect(sender, signal_index, senderMetaObject, receiver, -1, slot);
}
 
QMetaObject::Connection QObjectPrivate::connect(const QObject *sender, int signal_index, QtPrivate::QSlotObjectBase *slotObj, Qt::ConnectionType type)
{
    return QObjectPrivate::connect(sender, signal_index, sender, slotObj, type);
}
 
QMetaObject::Connection QObjectPrivate::connect(const QObject *sender, int signal_index,
                                                const QObject *receiver,
                                                QtPrivate::QSlotObjectBase *slotObj,
                                                Qt::ConnectionType type)
{
    if (!sender) {
        qCWarning(lcConnect, "QObject::connect: invalid nullptr parameter");
        if (slotObj)
            slotObj->destroyIfLastRef();
        return QMetaObject::Connection();
    }
    const QMetaObject *senderMetaObject = sender->metaObject();
    signal_index = methodIndexToSignalIndex(&senderMetaObject, signal_index);
 
    return QObjectPrivate::connectImpl(sender, signal_index, receiver, /*slot*/ nullptr, slotObj,
                                       type, /*types*/ nullptr, senderMetaObject);
}
 
bool QObjectPrivate::disconnect(const QObject *sender, int signal_index, void **slot)
{
    return QObjectPrivate::disconnect(sender, signal_index, sender, slot);
}
 
bool QObjectPrivate::disconnect(const QObject *sender, int signal_index, const QObject *receiver,
                                void **slot)
{
    const QMetaObject *senderMetaObject = sender->metaObject();
    signal_index = methodIndexToSignalIndex(&senderMetaObject, signal_index);
 
    return QMetaObjectPrivate::disconnect(sender, signal_index, senderMetaObject, receiver, -1,
                                          slot);
}
 
bool QObjectPrivate::disconnect(QObjectPrivate::Connection *c)
{
    if (!c)
        return false;
    QObject *receiver = c->receiver.loadRelaxed();
    if (!receiver)
        return false;
 
    QBasicMutex *senderMutex = signalSlotLock(c->sender);
    QBasicMutex *receiverMutex = signalSlotLock(receiver);
 
    QObjectPrivate::ConnectionData *connections;
    {
        QOrderedMutexLocker locker(senderMutex, receiverMutex);
 
        // 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;
 
        connections = QObjectPrivate::get(c->sender)->connections.loadRelaxed();
        Q_ASSERT(connections);
        connections->removeConnection(c);
 
        c->sender->disconnectNotify(QMetaObjectPrivate::signal(c->sender->metaObject(), c->signal_index));
        // We must not hold the receiver mutex, else we risk dead-locking; we also only need the sender mutex
        // It is however vital to hold the senderMutex before calling cleanOrphanedConnections, as otherwise
        // another thread might modify/delete the connection
        if (receiverMutex != senderMutex) {
            receiverMutex->unlock();
        }
        connections->cleanOrphanedConnections(c->sender, ConnectionData::AlreadyLockedAndTemporarilyReleasingLock);
        senderMutex->unlock(); // now both sender and receiver mutex have been manually unlocked
        locker.dismiss(); // so we dismiss the QOrderedMutexLocker
    }
 
    return true;
}
 
QMetaObject::Connection::Connection(const QMetaObject::Connection &other) : d_ptr(other.d_ptr)
{
    if (d_ptr)
        static_cast<QObjectPrivate::Connection *>(d_ptr)->ref();
}
 
QMetaObject::Connection &QMetaObject::Connection::operator=(const QMetaObject::Connection &other)
{
    if (other.d_ptr != d_ptr) {
        if (d_ptr)
            static_cast<QObjectPrivate::Connection *>(d_ptr)->deref();
        d_ptr = other.d_ptr;
        if (other.d_ptr)
            static_cast<QObjectPrivate::Connection *>(other.d_ptr)->ref();
    }
    return *this;
}
 
QMetaObject::Connection::Connection() : d_ptr(nullptr) {}
 
QMetaObject::Connection::~Connection()
{
    if (d_ptr)
        static_cast<QObjectPrivate::Connection *>(d_ptr)->deref();
}
 
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.loadRelaxed();
}
 
 
QT_END_NAMESPACE
 
#include "moc_qobject.cpp"