connect() terminates the program

[saman_artorious]

I get a weird program termination when I use connect() in my code. I checked the code properly, i don't know where the mistake comes from:

I call construct the control object in MainWindow and call its init()

void Control::initObjects()
{
    logger  = new ErrorLogger();
 
   X    = new Xr();
 
   Y  = new Y();
 
    Z = new Z();
 
    rs_485  = new rs485();
 
    establishConnections();
}
 
void Control::establishConnections()
{
    connect(X       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(Y       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(Z       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(rs485 , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
}

void Control::initObjects()
{
    logger  = new ErrorLogger();

   X    = new Xr();

   Y  = new Y();

    Z = new Z();

    rs_485  = new rs485();

    establishConnections();
}

void Control::establishConnections()
{
    connect(X       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(Y       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(Z       , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
    connect(rs485 , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
}

To copy to clipboard, switch view to plain text mode 

the last connect terminates my program, thought the first 3 work properly.

[alizadeh91]

Can't be because of rs485!!?? because you've made an object with name of rs_485. but you have used it with name of rs485 which is the class name. That could be the mistake

[saman_artorious]

Can't be because of rs485!!?? because you've made an object with name of rs_485. but you have used it with name of rs485 which is the class name. That could be the mistake

That was changed after pasting. it still jumps out when it is run.

[alizadeh91]

Seems somethings wrong with rs_485. Can't tell what is it unless you provide a simple example (attach simple source code)

[saman_artorious]

update: I found this warning in debug

&"warning: GDB: Failed to set controlling terminal: Inappropriate ioctl for device\n"

&"warning: GDB: Failed to set controlling terminal: Inappropriate ioctl for device\n"

To copy to clipboard, switch view to plain text mode 

Seems somethings wrong with rs_485. Can't tell what is it unless you provide a simple example (attach simple source code)

0	QMetaObject::activate(QObject*, int, int, void**)	/home/saman/Qt5.0.1/5.0.1/gcc/lib/libQt5Core.so.5		0xb735c540	
1	QMetaObject::activate(QObject*, QMetaObject const*, int, void**)	/home/saman/Qt5.0.1/5.0.1/gcc/lib/libQt5Core.so.5		0xb735d21b	
2	rs485::logMessage	moc_rs485.cpp	153	0x8064c12	
3	rs485::logConstruction	rs485.cpp	498	0x805661d	
4	MainWindow::MainWindow	mainwindow.cpp	27	0x804e8c0	
5	main	main.cpp	9	0x804e5f0

0	QMetaObject::activate(QObject*, int, int, void**)	/home/saman/Qt5.0.1/5.0.1/gcc/lib/libQt5Core.so.5		0xb735c540	
1	QMetaObject::activate(QObject*, QMetaObject const*, int, void**)	/home/saman/Qt5.0.1/5.0.1/gcc/lib/libQt5Core.so.5		0xb735d21b	
2	rs485::logMessage	moc_rs485.cpp	153	0x8064c12	
3	rs485::logConstruction	rs485.cpp	498	0x805661d	
4	MainWindow::MainWindow	mainwindow.cpp	27	0x804e8c0	
5	main	main.cpp	9	0x804e5f0

To copy to clipboard, switch view to plain text mode 

Debugging gives me this:

void rs485::logMessage(const char * _t1)
{
    void *_a[] = { 0, const_cast<void*>(reinterpret_cast<const void*>(&_t1)) };
    QMetaObject::activate(this, &staticMetaObject, 0, _a);
}

void rs485::logMessage(const char * _t1)
{
    void *_a[] = { 0, const_cast<void*>(reinterpret_cast<const void*>(&_t1)) };
    QMetaObject::activate(this, &staticMetaObject, 0, _a);
}

To copy to clipboard, switch view to plain text mode 

inside rs I have defined a signal

signals:
    void logMessage(const char* );

signals:
    void logMessage(const char* );

To copy to clipboard, switch view to plain text mode 

After rs object creation, I call its member function to trigger a sample signal for the logger to catch:

void rs485::logConstruction()
{
    emit logMessage("RS485 constructed:)");
}

void rs485::logConstruction()
{
    emit logMessage("RS485 constructed:)");
}

To copy to clipboard, switch view to plain text mode 

(this is done inside MainWindow):

connect(rs_485 , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));
 
    rs_485->printHello();
    rs_485->logConstruction();

connect(rs_485 , SIGNAL(logMessage(const char* )), logger, SLOT(logMessage(const char* )));

    rs_485->printHello();
    rs_485->logConstruction();

To copy to clipboard, switch view to plain text mode 

printHello Member works fine, but.... log construction jumps out!

---

Added after 25 minutes:

i found the problem,
tcsetattr(fd, TCSANOW, &portSettings) cannot succeed, it fails and closes the device.
that's why connect jumps outta program.

[amleto]

oh right! What's that got to do with emit logMessage(...)?

please read my sig for future reference!

[saman_artorious]

oh right! What's that got to do with emit logMessage(...)?

please read my sig for future reference!

because that terminated the program when I was trying to connect the object with another! though, the object is created successfully.
this is because tcsetattr() function gives back Input/Output error.

Well, this is a linux device problem, I will handle it myself. Thanks anyway.

bool rs485::rs485ConfigPort()
{
    termios portSettings;
 
    memset(&portSettings, 0, sizeof(portSettings));
 
    portSettings.c_cflag |= (CLOCAL | CREAD);
 
    cfsetispeed(&portSettings, B57600);
 
    portSettings.c_cflag &= ~PARENB;
 
    portSettings.c_cflag |= CS8;
 
    portSettings.c_cflag &= ~CSIZE;
 
    portSettings.c_cflag &= ~CSTOPB; //stop bit = 1
 
    //cfmakeraw(&portSettings);
 
    if (tcsetattr(fd, TCSANOW, &portSettings))
    {
        emit logMessage("Can not adjust port settings");
 
        close(fd);
        return false;
    }
 
    tcflush(fd, TCIFLUSH);
    return true;
}

bool rs485::rs485ConfigPort()
{
    termios portSettings;

    memset(&portSettings, 0, sizeof(portSettings));

    portSettings.c_cflag |= (CLOCAL | CREAD);

    cfsetispeed(&portSettings, B57600);

    portSettings.c_cflag &= ~PARENB;

    portSettings.c_cflag |= CS8;

    portSettings.c_cflag &= ~CSIZE;

    portSettings.c_cflag &= ~CSTOPB; //stop bit = 1

    //cfmakeraw(&portSettings);

    if (tcsetattr(fd, TCSANOW, &portSettings))
    {
        emit logMessage("Can not adjust port settings");

        close(fd);
        return false;
    }

    tcflush(fd, TCIFLUSH);
    return true;
}

To copy to clipboard, switch view to plain text mode 

[alizadeh91]

We are not mind reader!!! Here is a forum for Qt programming, so you can ask your questions about Qt Framework and anything related to it. Your question is not actually related to Qt.

[saman_artorious]

We are not mind reader!!! Here is a forum for Qt programming, so you can ask your questions about Qt Framework and anything related to it. Your question is not actually related to Qt.

You are right, I did not know this before I found the problem, I thought it was related to QObjects. anyway, I solved the problem, it was a device problem.