qt网络事件之QSocketNotifier

简介

QSocketNotifier用于处理网络事件的,即事件处理器

结构

QSocketNotifier +qintptr socket() +Type type() +bool isEnabled() +void setEnabled(bool) +void activated(int socket, QPrivateSignal) #bool event(QEvent *) QSocketNotifierPrivate +qintptr sockfd +QSocketNotifier::Type sntype +bool snenabled

qintptr socket()：表示对应的网络套接字

Type type()：表示关注的事件类型，使用枚举表示

cpp 复制代码

enum Type { Read, Write, Exception }

bool isEnabled()：表示对应的是否注册到事件分发顺器中

void setEnabled(bool)：是槽函数，表示是否将套接字注册到事件分发器中

cpp 复制代码

void QSocketNotifier::setEnabled(bool enable)
{
    Q_D(QSocketNotifier);
    if (d->sockfd < 0)
        return;
    if (d->snenabled == enable)                        
        return;
    d->snenabled = enable;

    if (!d->threadData->hasEventDispatcher())
        return;
    if (Q_UNLIKELY(thread() != QThread::currentThread())) {
        return;
    }
    if (d->snenabled)
        d->threadData->eventDispatcher.loadRelaxed()->registerSocketNotifier(this);
    else
        d->threadData->eventDispatcher.loadRelaxed()->unregisterSocketNotifier(this);
}

void activated(int socket, QPrivateSignal)：信号，在event事件处理函数中，如果事件类型为QEvent::SockAct或者QEvent::SockClose，会触发该信号

bool event(QEvent *)：事件处理函数

cpp 复制代码

bool QSocketNotifier::event(QEvent *e)
{
    Q_D(QSocketNotifier);
    // Emits the activated() signal when a QEvent::SockAct or QEvent::SockClose is
    // received.
    if (e->type() == QEvent::ThreadChange) {
        if (d->snenabled) {
            QMetaObject::invokeMethod(this, "setEnabled", Qt::QueuedConnection,
                                      Q_ARG(bool, d->snenabled));
            setEnabled(false);
        }
    }
    QObject::event(e);                        // will activate filters
    if ((e->type() == QEvent::SockAct) || (e->type() == QEvent::SockClose)) {
        emit activated(d->sockfd, QPrivateSignal());
        return true;
    }
    return false;
}

触发网络事件

QEventDispatcherUNIX QEventDispatcherUNIXPrivate QSocketNotifier processEvents qt_safe_poll activateSocketNotifiers event emit activated QEventDispatcherUNIX QEventDispatcherUNIXPrivate QSocketNotifier