thread not start() sometimes

kickoune103

i have application to receive value of different protocol serial ethernet .....
i have List of protocol, i have members qThread.

in this thread i have local object serial, ethernet, object communication is in thread.

ex class: serialThread

serialThread::serialThread(Protocole *Parent): ThreadProt( this, Parent )
{
qDebug() << "new serial thread:" << this;
setParent(Parent); //parent = protocole
}

run is implemented here

void serialThread::run()
{

qDebug() << "thread serial:" << QThread::currentThreadId();

serial l_serial(this,m_prot);

 exec();
}

  class ThreadProt : public QThread

i have created threadProt to group code for different protocol.

kill thread kill parent with deleteLater (serialThread)
signals to thread

access object local in run() thread

  ThreadProt::ThreadProt(QObject*pParent,Protocole* pProt)
  {
 qDebug() << "new threadProt:" << this;
 setParent(pParent); //serialthread        Modbus thread
 m_prot = pProt;
 m_o_thread = NULL;
connect(this, SIGNAL(finished())   ,pParent  , SLOT(deleteLater())   );
  //qthread fini on détruit le parent
  start();

}

sometimes thread not start(), not execute run() in serial thread.

why is not the solution to inherit of qthread???

i have restart my code with this structure.
i prefer not use move to thread and have my object in local of thread.

i think is better but this design not work fine if you have Intermediaire class

Christian Ehrlicher

Where and how do you instantiate ThreadProt?

kickoune103

Serialthread constructor call threadprot in constructor and call start().

Why this design is bad ?

Christian Ehrlicher

And where is serialThread instantiated?
Setting itself as parent is not such a good idea btw:

serialThread::serialThread(Protocole Parent): ThreadProt( this, Parent )
ThreadProt::ThreadProt(QObjectpParent,Protocole* pProt) {
setParent(pParent);
...

kickoune103

ok, i don't know if threadProt must be use setParent.

thread is started startProt() with call in Q_INVOKABLE dashBoardStart() function in QML.

void App::dashBoardStart()
{
  quint32 l_prot;


qDebug() << "start dashboard" << LstProt.length();

if (LstProt.count() ==0)
    return;

for (l_prot=0;l_prot < LstProt.count();l_prot++)
{
    Protocole* l_pt =  LstProt[l_prot].value<Protocole*>();

    if (m_lst_prot_ready)
        m_lst_prot_ready->append(false);


    l_pt->startProt();
}//Finsi
}

bool Protocole::startProt()
 {
quint8 l_i;
quint32 BaudRateCustom=0;
bool l_ret = false;

/* reset erreur protocol */
CrcError = 0;
counter   = 0;
periodeMs = 0;

 qDebug() << "startProt:" << this << iLiaison << iProt <<"special:"<< isProtSpecial() << m_liaison.ConfigRs;

if (isProtSpecial())
{
    if (isModbus())
    {

         if (this->m_obj_device.Modbus ==NULL)
             this->m_obj_device.Modbus = new ModbusThread(this);

    }
}
else
switch (iLiaison)
{

    case LIAISON_RS:

    //allocation du thread serial
    if (m_liaison.ConfigRs == NULL)
        m_liaison.ConfigRs = new serialThread(this);

    break;

case LIAISON_ADC:
    if (m_liaison.adc != NULL)
        this->m_liaison.adc->lanceThread();
    break;

case LIAISON_ETH:
        m_liaison.ConfigEth->start();
    break;

case LIAISON_CAN:

    if (m_liaison.ConfigCAN == NULL)
        m_liaison.ConfigCAN = new CanThread(this);

    break;
}
//if (l_ret)
//    isActive = true;

return (l_ret);
}

any idea because thread is not started if is called in inherit class?

kickoune103

thread isRunning = true isStarted is call but not call run() in this case.

Christian Ehrlicher

if (m_liaison.ConfigRs == NULL)
   m_liaison.ConfigRs = new serialThread(this);

Is m_liaison.ConfigRs a QPointer? Otherwise I don't see how you would reuse (and restart) the thread a second time. Especially since you're calling deleteLater so m_liaison.ConfigRs will become a dangling pointer afterwards.

kickoune103

the problem is at start up, not a pointeur problem because constructor is started.

strange: in my windows pc at work, no problems.

on my mac, problem, i will compare version of qt.
my mac have qt 5.9
my pc have qt 5.11

i will update my qt in my MAC.

Christian Ehrlicher

Try to call start() outside the ctor