为什么删除Qt(QSslSocket)对象会导致崩溃

Question

我真的很难过,希望有人知道我的问题.

我有一个非常简单的SSL客户端和服务器.连接很好.沟通很好.当客户端与服务器断开连接时,会出现问题.这会在服务器上触发一个在SLOT中处理的信号error_handler(QAbstractSocket::SocketError in_error).在那个函数中,sslSocket对象必须被删除,我想.

但是这样做会导致服务器出现故障.我不明白发生了什么.我希望这很简单,但显然我缺少一些Qt(或其他)概念.

有人可以帮忙吗？

基本服务器代码:

void SSLServer::incomingConnection(int sd)
{
    sslSocket = new SSLSocket(this);
    if( sslSocket->setSocketDescriptor(sd))
    {
        QFile sslkeyfile(privKey_);
        sslSocket->setPrivateKey(QSslKey(sslkeyfile.readAll(),QSsl::Rsa));

        QFile cliCertFile(serverCert_);
        sslSocket->setLocalCertificate(QSslCertificate(cliCertFile.readAll()));

        QFile certFile(caCert_);
        sslSocket->addCaCertificate(QSslCertificate(certFile.readAll()));

        sslSocket->setPeerVerifyMode(QSslSocket::VerifyPeer);
        sslSocket->setProtocol(QSsl::SslV3);

        connect(sslSocket, SIGNAL(error(QAbstractSocket::SocketError)),
                this, SLOT(error_handler(QAbstractSocket::SocketError)));
        connect(sslSocket, SIGNAL(sslErrors(QList<QSslError>)),
                this, SLOT(ssl_error_handler(QList<QSslError>)));
        connect(sslSocket, SIGNAL(encrypted()), this,
                SLOT(ready()));
        connect(sslSocket, SIGNAL(readyRead()), this,
                SLOT(read_data_from_client()));

        sslSocket->startServerEncryption();
        if(!sslSocket->waitForEncrypted())
        {
            qDebug() << "failed to perform SSL handshake with client";
            return;
        }
    }

}

void SSLServer::read_data_from_client()
{
    QByteArray qstrbytes = sslSocket->readAll();
    qDebug() << Q_FUNC_INFO << qstrbytes;
}

void SSLServer::ready()
{
    QSslCertificate clientCert = sslSocket->peerCertificate();
    qDebug() << clientCert.isValid();
}

void SSLServer::error_handler(QAbstractSocket::SocketError in_error)
{
    qDebug() << Q_FUNC_INFO << in_error;
    if(in_error == QAbstractSocket::RemoteHostClosedError)
    {
        delete sslSocket; //// line causes crash !!!!!!
    }
}

Answer 1

使用QObject::deleteLater(),而不是delete因为QSslSocket继承QObject.当您只是delete对象时,您仍可能在套接字上收到导致崩溃的消息.

sslSocket->deleteLater();

当您调用时deleteLater(),Qt会自动断开所有插槽和信号,并在没有挂起事件传递给对象后调用对象析构函数.有关QObject::~QObject()更多信息,请参阅