airspy_close() blocks for ever if disconnect from USB unconditionally

[AlbrechtL]

When the airspy mini is disconnected from USB unconditionally then the function airspy_stop_rx() reports AIRSPY_ERROR_LIBUSB(-1000) which is as expected. But the function airspy_close() blocks for ever.

I use both functions during the shutdown of my application. Because of airspy_close() the program is not quit correctly.

https://github.com/AlbrechtL/welle.io/blob/56504bcd40544e32987ceb3832715e3cc0f1c821/src/input/airspy_sdr.cpp#L84

CAirspy::~CAirspy(void)
{
    if (device) {
        int result = airspy_stop_rx(device);
        if (result != AIRSPY_SUCCESS) {
            std::clog  << "Airspy: airspy_stop_rx () failed:" << airspy_error_name((airspy_error)result) << "(" << result << ")" << std::endl;
        }

        result = airspy_close(device);
        if (result != AIRSPY_SUCCESS) {
            std::clog  << "Airspy: airspy_close () failed:" << airspy_error_name((airspy_error)result) << "(" << result << ")" << std::endl;
        }
    }

    airspy_exit();
}

What can I do to close the airspy driver correctly even if the airspy in disconnected?

[bvernoux]

1) Could you provide more details on how to reproduce it ?

• Thanks to add details on PC, OS and libusb version used (thanks to test with latest version v1.0.23: libusb 1.0.23)

2) Could you reproduce it with https://github.com/airspy/airspyone_host/blob/master/airspy-tools/src/airspy_rx.c

• If yes thanks to provide details so we could check how to improve that (even if I'm afraid the issue comes from libusb which is not robust about that to be confirmed...)
• Thanks to provide more details on where it is frozen (you can create a MiniDump with SysInternals Process Explorer of the App airspy_rx when it is in frozen state for example ...)