ConfiguratorWindow::resetDevice() requires refactoring

[samuelfmlourenco]

In the present moment, inside "configuratorwindow.cpp", from lines 648 to 677, we have resetDevice() implemented as follows:

// Resets the device
void ConfiguratorWindow::resetDevice()
{
    int errcnt = 0;
    QString errstr;
    cp2130_.reset(errcnt, errstr);
    cp2130_.close();  // Important! - This should be done always, even if the previous reset operation shows an error, because an error doesn't mean that a device reset was not effected
    int err;
    for (int i = 0; i < ENUM_RETRIES; ++i) {  // Verify enumeration according to the number of times set by "ENUM_RETRIES" [10]
        NonBlocking::msleep(500);  // Wait 500ms each time
        err = cp2130_.open(vid_, pid_, serialstr_);
        if (err != 2) {  // Retry only if the device was not found yet (as it may take some time to enumerate)
            break;
        }
    }
    if (err == CP2130::ERROR_INIT) {  // Failed to initialize libusb
        QMessageBox::critical(this, tr("Critical Error"), tr("Could not reinitialize libusb.\n\nThis is a critical error and execution will be aborted."));
        exit(EXIT_FAILURE);  // This error is critical because libusb failed to initialize
    } else if (err == CP2130::ERROR_NOT_FOUND) {  // Failed to find device
        err_ = true;
        errmsg_ = tr("Device disconnected.\n\nThe corresponding window will be disabled.");  // Since version 1.2, the error message is not shown here
    } else if (err == CP2130::ERROR_BUSY) {  // Failed to claim interface
        err_ = true;
        errmsg_ = tr("Device ceased to be available. It could be in use by another application.\n\nThe corresponding window will be disabled.");  // Same as above
    } else {
        readDeviceConfiguration();
        this->setWindowTitle(tr("CP2130 Configurator (S/N: %1)").arg(serialstr_));
        displayConfiguration(deviceConfig_);
    }
}

However, similarly to what happens with openDevice() (see issue https://github.com/bloguetronica/cp2130-conf/issues/16), this function assumes that the device was successfully reopened if CP2130::open() doesn't return any error values, that is, doesn't return CP2130::ERROR_INIT, CP2130::ERROR_NOT_FOUND or CP2130::ERROR_BUSY. However, if in the future CP2130::open() is changed so it returns new error conditions, this will potentially cause issues. Thus, resetDevice() should be rewritten. Below is a proposal:

// Resets the device
void ConfiguratorWindow::resetDevice()
{
    int errcnt = 0;
    QString errstr;
    cp2130_.reset(errcnt, errstr);
    cp2130_.close();  // Important! - This should be done always, even if the previous reset operation shows an error, because an error doesn't mean that a device reset was not effected
    int err;
    for (int i = 0; i < ENUM_RETRIES; ++i) {  // Verify enumeration according to the number of times set by "ENUM_RETRIES" [10]
        NonBlocking::msleep(500);  // Wait 500ms each time
        err = cp2130_.open(vid_, pid_, serialstr_);
        if (err != CP2130::ERROR_NOT_FOUND) {  // Retry only if the device was not found yet (as it may take some time to enumerate)
            break;
        }
    }
    if (err == CP2130::SUCCESS) {  // Device was successfully reopened
        readDeviceConfiguration();
        this->setWindowTitle(tr("CP2130 Configurator (S/N: %1)").arg(serialstr_));
        displayConfiguration(deviceConfig_);
    } else if (err == CP2130::ERROR_INIT) {  // Failed to initialize libusb
        QMessageBox::critical(this, tr("Critical Error"), tr("Could not reinitialize libusb.\n\nThis is a critical error and execution will be aborted."));
        exit(EXIT_FAILURE);  // This error is critical because libusb failed to initialize
    } else if (err == CP2130::ERROR_NOT_FOUND) {  // Failed to find device
        err_ = true;
        errmsg_ = tr("Device disconnected.\n\nPlease reconnect it and try again.");  // Since version 1.2, the error message is not shown here
    } else if (err == CP2130::ERROR_BUSY) {  // Failed to claim interface
        err_ = true;
        errmsg_ = tr("Device ceased to be available. It could be in use by another application.");  // Same as above
    }
}

If ITUSB2Device::open() returns an error value that is not expected at this time, this new algorithm will do nothing. Note that this refactor also solves issue https://github.com/bloguetronica/cp2130-conf/issues/13.

[samuelfmlourenco]

Code refactored in version 1.4.