QSslSocket reconnect to host

If I am trying to connect to an invalid host, and, after the connection fails, I try to connect to a valid host, the connection still fails.

Code:

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void testSoc::test()
{
   switch (state)
   {
      case 0:
      case 2:
      case 4:
         qDebug ("Connecting to a valid host. Should be Ok");
         timeout->start(10000);
         soc->connectToHost(VALID_HOST, VALID_PORT);
         break;
      case 1:
         qDebug ("Connecting to a invalid port. Should fail");
         timeout->start(10000);
         soc->connectToHost(VALID_HOST, INVALID_PORT);
         break;
      case 3:
         qDebug ("Connecting to a invalid host. Should fail");
         timeout->start(10000);
         soc->connectToHost(INVALID_HOST, VALID_PORT);
         break;
   }
}
void testSoc::checkConnection()
{
   timeout->stop();
   if (soc->state() == QAbstractSocket::ConnectedState)
   {
      connected();
   } else {
      qDebug ("Connection failed");
      soc->disconnectFromHost();
      if (soc->state() != QAbstractSocket::UnconnectedState)
         soc->waitForDisconnected();
      soc->close();
      //delete soc;
      //soc = new QSslSocket;
      state ++;
      test();
   }
}
 
* and of course there is 
 
 connect (soc, SIGNAL(connected()),
        this, SLOT(connected()));
   connect (timeout, SIGNAL(timeout()),
        this, SLOT(checkConnection()));

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In this code, all gives the expected results, except for case 4 (including case 2, reconnecting after trying to connect to a valid host, with invalid port)

deleting and re-creating the socket does not help
(using Qt 4.4.3)

Hi,

did you find a solution for your problem?

I have no experience with QSslSocket, but for QTcpSocket I never managed to establish a connection after an initial failure. I usually delete the failed QTcpSocket and create a new one for the next try. This seems to work fine without excessive overhead.
For some reason I can't remember right now I disconnected the socket before deleting. Here the snippet from my code wich trigger the reconnect attempt:

Code:

---

if(socket->state()!=QAbstractSocket::ConnectedState)
		{
			disconnect(socket, nullptr, nullptr, nullptr);
			socket->close();
			socket->deleteLater();
			socket=nullptr;
			lastErr_=1002;
			lastErrStr_=QString("NetCon: connection attempt timed out after %1 ms").arg(toCon_);
			qWarning()<<lastErrStr_;
			emit errorSig(lastErr_);
			emit readySig(false);
			if(!isServer_)
			{
				if(testOnly)
					qInfo()<<"test only - canceling reconnect attempt";
				if(toCon_<86400000)
					toCon_*=2; // will level off at 2^27 ~= 37h retry inteval
				qWarning()<<"NetCon: retry to connect to"<<address_.toString();
				start();
			}
		}

---

Not pretty, but this variation on the original code works fine for me without recreating sockets etc.:

Code:

---

#ifndef TESTSOC_H
#define TESTSOC_H
 
#include <QTimer>
#include <QTcpSocket>
#include <QDebug>
 
 
class testSoc: public QObject {
    Q_OBJECT
    int state;
    QTcpSocket *soc;
    QTimer *timeout;
public:
    explicit testSoc(QObject *p = nullptr);
    ~testSoc();
    void test();
 
private slots:
    void connected();
    void handleError(QAbstractSocket::SocketError socketError);
    void handleTimeout();
 
private:
    void nextState();
};
 
#endif // TESTSOC_H

---

Code:

---

#include "testSoc.h"
 
#define VALID_HOST "www.google.com"
#define VALID_PORT 80
#define INVALID_HOST "localhost"
#define INVALID_PORT 81
#define TIMEOUT 3000
 
testSoc::testSoc(QObject *p):
    QObject(p),
    state(0),
    soc(nullptr),
    timeout(nullptr)
{
    soc = new QTcpSocket(this);
    connect (soc, SIGNAL(connected()), this, SLOT(connected()));
    connect (soc, SIGNAL(error(QAbstractSocket::SocketError)), this, SLOT(handleError(QAbstractSocket::SocketError)));
 
    timeout = new QTimer(this);
    timeout->setSingleShot(true);
    timeout->setInterval(TIMEOUT);
    connect (timeout, SIGNAL(timeout()), this, SLOT(handleTimeout()));
}
 
testSoc::~testSoc() {
}
 
void testSoc::test()
{
    switch (state)
    {
    case 0:
    case 2:
    case 4:
        qDebug () << "State" << state << "Connecting to a valid host. Should be Ok";
        timeout->start();
        soc->connectToHost(VALID_HOST, VALID_PORT);
        break;
    case 1:
        qDebug () << "State" << state << "Connecting to a invalid port. Should fail";
        timeout->start();
        soc->connectToHost(VALID_HOST, INVALID_PORT);
        break;
    case 3:
        qDebug () << "State" << state << "Connecting to a invalid host. Should fail";
        timeout->start();
        soc->connectToHost(INVALID_HOST, VALID_PORT);
        break;
    }
}
 
void testSoc::connected() {
    timeout->stop();
    qDebug() << "State" << state << "Connected to" << soc->peerName() << "port" << soc->peerPort();
    // do some work here
    soc->disconnectFromHost();
    nextState();
}
 
void testSoc::handleError(QAbstractSocket::SocketError socketError) {
    timeout->stop();
    qDebug() << "State" << state << "Error reported" << socketError;
    nextState();
}
 
void testSoc::handleTimeout()
{
    timeout->stop();
    qDebug () << "State" << state << "Connection time out";
    // Using disconnectFromHost() on a host that was never connected 
    // just causes a long pause for some internal timeout.
    soc->abort(); 
    nextState();
}
 
void testSoc::nextState()
{
    state = (state + 1) % 5;
    test();
}

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Code:

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#include <QApplication>
#include "testSoc.h"
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    testSoc t;
    t.test();
    return a.exec();
}

---