Fix calibration bug + improve device shutdown

Software/PC_Application/LibreVNA-GUI/Device/device.cpp

@@ -22,7 +22,8 @@ static constexpr USBID IDs[] = {
 USBInBuffer::USBInBuffer(libusb_device_handle *handle, unsigned char endpoint, int buffer_size) :
     buffer_size(buffer_size),
     received_size(0),
-    inCallback(false)
+    inCallback(false),
+    cancelling(false)
 {
     buffer = new unsigned char[buffer_size];
     memset(buffer, 0, buffer_size);
@@ -34,6 +35,7 @@ USBInBuffer::USBInBuffer(libusb_device_handle *handle, unsigned char endpoint, i
 USBInBuffer::~USBInBuffer()
 {
     if(transfer) {
+        cancelling = true;
         libusb_cancel_transfer(transfer);
         // wait for cancellation to complete
         mutex mtx;
@@ -67,6 +69,13 @@ int USBInBuffer::getReceived() const
 
 void USBInBuffer::Callback(libusb_transfer *transfer)
 {
+    if(cancelling || (transfer->status == LIBUSB_TRANSFER_CANCELLED)) {
+        // destructor called, do not resubmit
+        libusb_free_transfer(transfer);
+        this->transfer = nullptr;
+        cv.notify_all();
+        return;
+    }
 //    qDebug() << libusb_error_name(transfer->status);
     switch(transfer->status) {
     case LIBUSB_TRANSFER_COMPLETED:
@@ -111,11 +120,7 @@ void USBInBuffer::Callback(libusb_transfer *transfer)
         // nothing to do
         break;
     case LIBUSB_TRANSFER_CANCELLED:
-        // destructor called, do not resubmit
+        // already handled before switch-case
-        libusb_free_transfer(transfer);
-        this->transfer = nullptr;
-        cv.notify_all();
-        return;
         break;
     }
     // Resubmit the transfer

Software/PC_Application/LibreVNA-GUI/Device/device.h

@@ -40,6 +40,7 @@ private:
     int buffer_size;
     int received_size;
     bool inCallback;
+    bool cancelling;
     std::condition_variable cv;
 };
 

Software/PC_Application/LibreVNA-GUI/VNA/vna.cpp

@@ -1160,7 +1160,7 @@ void VNA::StartCalibrationMeasurements(std::set<CalibrationMeasurement::Base*> m
     }
     // Stop sweep
     running = false;
-    SettingsChanged();
+    ConfigureDevice();
     calMeasurements = m;
     // Delete any already captured data of this measurement
     cal.clearMeasurements(m);
@@ -1187,6 +1187,7 @@ void VNA::StartCalibrationMeasurements(std::set<CalibrationMeasurement::Base*> m
         cal.clearMeasurements(calMeasurements);
     });
     // Trigger sweep to start from beginning
+    running = true;
     ConfigureDevice(true, [=](bool){
         // enable calibration measurement only in transmission callback (prevents accidental sampling of data which was still being processed)
         calMeasuring = true;
@@ -1707,15 +1708,14 @@ void VNA::ConfigureDevice(bool resetTraces, std::function<void(bool)> cb)
     } else {
         if(window->getDevice()) {
             changingSettings = true;
-            // single sweep finished
             window->getDevice()->setIdle([=](bool){
-                emit sweepStopped();
                 changingSettings = false;
             });
         } else {
             emit sweepStopped();
             changingSettings = false;
         }
+        emit sweepStopped();
     }
 }
 

Software/PC_Application/LibreVNA-GUI/preferences.cpp

@@ -502,10 +502,10 @@ void Preferences::load()
     for(auto d : descr) {
         try {
             d.var.setValue(settings.value(d.name, d.def));
-            qDebug() << "Setting" << d.name << "is set to" << d.var.value();
+//            qDebug() << "Setting" << d.name << "is set to" << d.var.value();
         } catch (const exception& e){
             d.var.setValue(d.def);
-            qDebug() << "Setting" << d.name << "reset to default:" << d.def;
+//            qDebug() << "Setting" << d.name << "reset to default:" << d.def;
         }
     }
     nonTrivialParsing();

Software/PC_Application/LibreVNA-GUI/preferences.h

@@ -174,9 +174,7 @@ public:
 
 private:
     Preferences() :
-     TCPoverride(false) {
+     TCPoverride(false) {}
-        qDebug() << "Pref constructor: " << &compoundDeviceJSON;
-    }
     static Preferences instance;
 
     const std::vector<Savable::SettingDescription> descr = {{