Why program crash when USB port changes?

[viniltc]

Hi ,

I have got a strange issue, and I'm banging my head to debug it!

I have got a serial device connected to the PC.

I have a button called "log" when clicked, it goes to the following slot and basically does some file manipulations.

When I was testing this, it all worked fine.

Now reconnect the device to a different USB port, now when I click to open the "log" the program crashes.

This happens only when reconnecting the device to a different USB port.

When I tried to debug it it shows the message:

I can see it is something related to a range of a QList. But I don't know why the program crashes and throw this message in some USB ports!??
And other parts of the program works fine (I mean program crashes only when I click the log button)

here is what I'm doing when "log" button is clicked

void StageOneMain::on_pushButton_log_clicked()
{

    QString namestring = "log_file_"+pLabel;
    QString filename = "logfilename.txt";
    QString newfilename = "log_file_"+pLabel+".txt";


    QFile originalFile(filename), newFile(newfilename);

    if(!originalFile.open(QIODevice::ReadOnly|QIODevice::Text))
    {
        qDebug() << "Error opening original log file: "<<originalFile.errorString();
    }


    QTextStream instream(& originalFile);

    QRegExp rx("(\\ |\\,|\\.|\\:|\\t)");
    QRegExp regExp_int (QLatin1Literal("[^0-9]+")); // reg ex to extract integer from a string



    if(newFile.open(QIODevice::WriteOnly|QIODevice::Text))
    {

        QTextStream outstream(& newFile);

       outstream<<"Date and Time of last log access: "<<QDateTime::currentDateTime().toString()<<"\n\n"; // to add date and time
       outstream<<"Stimulator serial port details: "<<"\n\n";

        foreach (const QSerialPortInfo &info, QSerialPortInfo::availablePorts()) {
            QString s = QObject::tr("Port: ") + info.portName() + "\n"
                    + QObject::tr("Description: ") + info.description() + "\n"
                    + QObject::tr("Manufacturer: ") + info.manufacturer() + "\n"
                    + QObject::tr("Vendor Identifier: ") + (info.hasVendorIdentifier() ? QString::number(info.vendorIdentifier(), 16) : QString()) + "\n"
                    + QObject::tr("Product Identifier: ") + (info.hasProductIdentifier() ? QString::number(info.productIdentifier(), 16) : QString()) + "\n";
              outstream<<s<<'\n';}



        int linecount_1 = 0;

        while(linecount_1<6){

            QString line = instream.readLine();

            if(linecount_1== 0)
            {
                outstream <<line<< '\n';
            }
            if(linecount_1== 1)
            {
                outstream <<line<< '\n';
            }
            if(linecount_1== 2)
            {

                outstream <<line<< '\n';
            }
            if(linecount_1== 3)
            {
                outstream <<line<< '\n';
            }
            if(linecount_1== 4)
            {
                QStringList slist = line.split(regExp_int);
                qDebug()<<"Integer part of line 4"<<slist;
                int totTime = slist[1].toInt();

                if(totTime > 60 && totTime  < 3600)
                {
                    slist[1] =  QString::number(slist[1].toInt()/(60));
                    QString newline = "Power-on time: " + slist[1] +"min";
                    qDebug() << "newline: " << newline;
                    outstream <<newline<< '\n';
                }
                else if(totTime  > 3600)
                {
                    slist[1] =  QString::number(slist[1].toInt()/(60*60));
                    QString newline = "Power-on time: " + slist[1]+"hrs";
                    qDebug() << "newline: " << newline;
                    outstream <<newline<< '\n';
                }
                else
                {
                    QString newline = "Power-on time: " + slist[1] +"s";
                    qDebug() << "newline: " << newline;
                    outstream <<newline<< '\n';
                }



            }
            if(linecount_1== 5)
            {
                outstream <<line<< '\n';
            }





            ++linecount_1;
        }

        int nb_line = 6;
        while(!instream.atEnd())
        {

            QString line = instream.readLine();


            if(nb_line == 6 )
            {

                QString newline = "Phase\t\t\tCount\tMin time (s)\tMax time (s)\tTotal time (s)";
                outstream <<newline<< '\n';
            }


            if(nb_line == 7 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Rest\t\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                outstream <<newline<< '\n';

            }


            if(nb_line == 8 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Hand open (Key grip)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                outstream <<newline<< '\n';

            }

            if(nb_line == 9 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Finger Flexion (Key grip)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //    ui->textBrowser->append(newline);
                outstream <<newline<< '\n';

            }

            if(nb_line == 10 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Grip Phase (Key grip)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));

                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';



            }

            if(nb_line == 11 )
            {

                QStringList slist = line.split(rx);
                slist[0]= "Release Object (Key grip)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';


            }

            if(nb_line == 12 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Hand open (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 13 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Finger Flexion (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 14 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Grip Phase (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';


            }
            if(nb_line == 15 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Release Object (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 16 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Intensity (Key Grip)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 17 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Intensity (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 18 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Up (Key Grip)\t\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //   ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 19 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Down (Key Grip)\t\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //  ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 20 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Up (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //  ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 21 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Down (Palmar Grasp)\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                //  ui->textBrowser->append(newline);
                outstream <<newline<< '\n';
            }
            if(nb_line == 22 )
            {
                QStringList slist = line.split(rx);
                slist[0]= "Exercise phase\t\t";
                slist[2]= QString::number(slist[2].toInt()/(1000));
                slist[3]= QString::number(slist[3].toInt()/(1000));
                slist[4]= QString::number(slist[4].toInt()/(1000));
                QString newline = slist.join("\t");
                // ui->textBrowser->append(newline);
                outstream <<newline<< '\n';

            }

            ++nb_line;
        }


        originalFile.close();
        newFile.close();
        //originalFile.remove();
    }

      this->close()
      logwindow = new StimulatorLogWindow(pLabel, nullptr);
      logwindow -> setAttribute(Qt::WA_DeleteOnClose);
      logwindow -> show();

}

Can anyone spot an issue here?
Apologies if my explanation is vague

[J.Hilk]

@viniltc you do a bunch of splits of QString into QStringList - aka QList<QString> - and you do no checks, if the size of your list is actually the expected length. You simply access it via the [] operator.

I would start checking there

[viniltc]

@J-Hilk Hi, what check do you mean, can you show me an example please?

[J.Hilk]

@viniltc

QStringList slist = line.split(rx);
if(slist.size() >4) {
slist[0]= "Grip Phase (Key grip)\t";
slist[2]= QString::number(slist[2].toInt()/(1000));
slist[3]= QString::number(slist[3].toInt()/(1000));
slist[4]= QString::number(slist[4].toInt()/(1000));
} else {
    qDebug() << "Problem with string" << slist << line;
}

[viniltc]

@J-Hilk Thanks for the feedback. It solved! It was an issue related to printing serial port information