Much better missing SD Card detection

Plus other auto connect bug fixes

src/Vehicle/MultiVehicleManager.cc

@@ -123,6 +123,9 @@ void MultiVehicleManager::_vehicleHeartbeatInfo(LinkInterface* link, int vehicle
 
     setActiveVehicle(vehicle);
 
+    // Mark link as active
+    link->setActive(true);
+
 #if defined __android__
     if(_vehicles.count() == 1) {
         //-- Once a vehicle is connected, keep Android screen from going off

src/comm/LinkInterface.h

@@ -233,16 +233,6 @@ protected:
             _logDataRateToBuffer(_outDataWriteAmounts, _outDataWriteTimes, &_outDataIndex, byteCount, time);
     }
     
-protected slots:
-
-    /**
-     * @brief Read a number of bytes from the interface.
-     *
-     * @param bytes The pointer to write the bytes to
-     * @param maxLength The maximum length which can be written
-     **/
-    virtual void readBytes() = 0;
-
 private:
     /**
      * @brief logDataRateToBuffer Stores transmission times/amounts for statistics

src/comm/LinkManager.cc

@@ -32,6 +32,7 @@ This file is part of the QGROUNDCONTROL project
 #include <QList>
 #include <QApplication>
 #include <QDebug>
+#include <QSignalSpy>
 
 #ifndef __ios__
 #include "QGCSerialPortInfo.h"
@@ -121,7 +122,7 @@ LinkInterface* LinkManager::createConnectedLink(LinkConfiguration* config)
             if (serialConfig) {
                 pLink = new SerialLink(serialConfig);
                 if (serialConfig->usbDirect()) {
-                    _activeLinkCheckList.append(pLink);
+                    _activeLinkCheckList.append((SerialLink*)pLink);
                     if (!_activeLinkCheckTimer.isActive()) {
                         _activeLinkCheckTimer.start();
                     }
@@ -247,6 +248,7 @@ void LinkManager::disconnectLink(LinkInterface* link)
     }
     _deleteLink(link);
     if (_autoconnectConfigurations.contains(config)) {
+        qCDebug(LinkManagerLog) << "Removing disconnected autoconnect config" << config->name();
         _autoconnectConfigurations.removeOne(config);
         delete config;
     }
@@ -560,13 +562,17 @@ void LinkManager::_updateAutoConnectLinks(void)
         SerialConfiguration* linkConfig = _autoconnectConfigurations.value<SerialConfiguration*>(i);
         if (linkConfig) {
             if (!currentPorts.contains(linkConfig->portName())) {
-                // We don't remove links which are still connected even though at this point the cable may
-                // have been pulled. This is due to the fact that whether a serial port goes away from the
-                // list when the cable is pulled is OS dependant. By not disconnecting in this case, we keep
-                // things working the same across all OS.
-                if (!linkConfig->link() || !linkConfig->link()->isConnected()) {
-                    _confToDelete.append(linkConfig);
+                if (linkConfig->link()) {
+                    if (linkConfig->link()->isConnected()) {
+                        if (linkConfig->link()->active()) {
+                            // We don't remove links which are still connected which have been active with a vehicle on them
+                            // even though at this point the cable may have been pulled. Instead we wait for the user to
+                            // Disconnect. Once the user disconnects, the link will be removed.
+                            continue;
+                        }
+                    }
                 }
+                _confToDelete.append(linkConfig);
             }
         } else {
             qWarning() << "Internal error";
@@ -577,6 +583,9 @@ void LinkManager::_updateAutoConnectLinks(void)
     foreach (LinkConfiguration* pDeleteConfig, _confToDelete) {
         qCDebug(LinkManagerLog) << "Removing unused autoconnect config" << pDeleteConfig->name();
         _autoconnectConfigurations.removeOne(pDeleteConfig);
+        if (pDeleteConfig->link()) {
+            disconnectLink(pDeleteConfig->link());
+        }
         delete pDeleteConfig;
     }
 #endif // __ios__
@@ -842,10 +851,11 @@ bool LinkManager::isBluetoothAvailable(void)
 
 void LinkManager::_activeLinkCheck(void)
 {
+    SerialLink* link = NULL;
     bool found = false;
 
     if (_activeLinkCheckList.count() != 0) {
-        LinkInterface* link = _activeLinkCheckList.takeFirst();
+        link = _activeLinkCheckList.takeFirst();
         if (_links.contains(link) && link->isConnected()) {
             // Make sure there is a vehicle on the link
             QmlObjectListModel* vehicles = _toolbox->multiVehicleManager()->vehicles();
@@ -856,6 +866,8 @@ void LinkManager::_activeLinkCheck(void)
                     break;
                 }
             }
+        } else {
+            link = NULL;
         }
     }
 
@@ -863,7 +875,20 @@ void LinkManager::_activeLinkCheck(void)
         _activeLinkCheckTimer.stop();
     }
 
-    if (!found) {
-        qgcApp()->showMessage("Your Vehicle is not responding. If this continues please check that you have an SD Card inserted and try again.");
+    if (!found && link) {
+        // See if we can get an NSH prompt on this link
+        bool foundNSHPrompt = false;
+        link->writeBytes("\r", 1);
+        QSignalSpy spy(link, SIGNAL(bytesReceived(LinkInterface*, QByteArray)));
+        if (spy.wait(100)) {
+            QList<QVariant> arguments = spy.takeFirst();
+            if (arguments[1].value<QByteArray>().contains("nsh>")) {
+                foundNSHPrompt = true;
+            }
+        }
+
+        qgcApp()->showMessage(foundNSHPrompt ?
+                                  QStringLiteral("Please check to make sure you have an SD Card inserted in your Vehicle and try again.") :
+                                  QStringLiteral("Your Vehicle is not responding. If this continues shutdown QGroundControl, restart the Vehicle letting it boot completely, then start QGroundControl."));
     }
 }

src/comm/LinkManager.h

@@ -153,14 +153,6 @@ public:
     /// Disconnect the specified link
     Q_INVOKABLE void disconnectLink(LinkInterface* link);
 
-    /// Called to notify that a heartbeat was received with the specified information. Will transition
-    /// a link to active as needed.
-    ///     @param link Heartbeat came through on this link
-    ///     @param vehicleId Mavlink system id for vehicle
-    ///     @param heartbeat Mavlink heartbeat message
-    /// @return true: continue further processing of this message, false: disregard this message
-    bool notifyHeartbeatInfo(LinkInterface* link, int vehicleId, mavlink_heartbeat_t& heartbeat);
-
     // The following APIs are public but should not be called in normal use. The are mainly exposed
     // here for unit test code.
     void _deleteLink(LinkInterface* link);
@@ -244,9 +236,9 @@ private:
     bool _autoconnect3DRRadio;
     bool _autoconnectPX4Flow;
 
-    QTimer                  _activeLinkCheckTimer;                  ///< Timer which checks for a vehicle showing up on a usb direct link
-    QList<LinkInterface*>   _activeLinkCheckList;                   ///< List of links we are waiting for a vehicle to show up on
-    static const int        _activeLinkCheckTimeoutMSecs = 10000;   ///< Amount of time to wait for a heatbeat. Keep in mind ArduPilot stack heartbeat is slow to come.
+    QTimer              _activeLinkCheckTimer;                  ///< Timer which checks for a vehicle showing up on a usb direct link
+    QList<SerialLink*>  _activeLinkCheckList;                   ///< List of links we are waiting for a vehicle to show up on
+    static const int    _activeLinkCheckTimeoutMSecs = 15000;   ///< Amount of time to wait for a heatbeat. Keep in mind ArduPilot stack heartbeat is slow to come.
 
     static const char*  _settingsGroup;
     static const char*  _autoconnectUDPKey;

src/comm/LogReplayLink.cc

@@ -150,11 +150,6 @@ void LogReplayLink::_replayError(const QString& errorMsg)
     emit communicationError(_errorTitle, errorMsg);
 }
 
-void LogReplayLink::readBytes(void)
-{
-    // FIXME: This is a bad virtual from LinkInterface?
-}
-
 /// Since this is log replay, we just drops writes on the floor
 void LogReplayLink::writeBytes(const char* bytes, qint64 cBytes)
 {

src/comm/LogReplayLink.h

@@ -114,10 +114,6 @@ signals:
     void _pauseOnThread(void);
     void _setAccelerationFactorOnThread(int factor);
 
-protected slots:
-    // FIXME: This should not be part of LinkInterface. It is an internal link implementation detail.
-    virtual void readBytes(void);
-
 private slots:
     void _readNextLogEntry(void);
     void _play(void);

src/comm/MockLink.cc

@@ -121,11 +121,6 @@ MockLink::~MockLink(void)
     _disconnect();
 }
 
-void MockLink::readBytes(void)
-{
-    // FIXME: This is a bad virtual from LinkInterface?
-}
-
 bool MockLink::_connect(void)
 {
     if (!_connected) {

src/comm/MockLink.h

@@ -157,10 +157,6 @@ signals:
 public slots:
     virtual void writeBytes(const char *bytes, qint64 cBytes);
 
-protected slots:
-    // FIXME: This should not be part of LinkInterface. It is an internal link implementation detail.
-    virtual void readBytes(void);
-
 private slots:
     void _run1HzTasks(void);
     void _run10HzTasks(void);

src/comm/SerialLink.cc

@@ -93,34 +93,6 @@ void SerialLink::writeBytes(const char* data, qint64 size)
     }
 }
 
-/**
- * @brief Read a number of bytes from the interface.
- *
- * @param data Pointer to the data byte array to write the bytes to
- * @param maxLength The maximum number of bytes to write
- **/
-void SerialLink::readBytes()
-{
-    if(_port && _port->isOpen()) {
-        const qint64 maxLength = 2048;
-        char data[maxLength];
-        _dataMutex.lock();
-        qint64 numBytes = _port->bytesAvailable();
-
-        if (numBytes > 0) {
-            /* Read as much data in buffer as possible without overflow */
-            if(maxLength < numBytes) numBytes = maxLength;
-
-            _logInputDataRate(numBytes, QDateTime::currentMSecsSinceEpoch());
-
-            _port->read(data, numBytes);
-            QByteArray b(data, numBytes);
-            emit bytesReceived(this, b);
-        }
-        _dataMutex.unlock();
-    }
-}
-
 /**
  * @brief Disconnect the connection.
  *
@@ -267,8 +239,7 @@ bool SerialLink::_hardwareConnect(QSerialPort::SerialPortError& error, QString&
 void SerialLink::_readBytes(void)
 {
     qint64 byteCount = _port->bytesAvailable();
-    if (byteCount)
-    {
+    if (byteCount) {
         QByteArray buffer;
         buffer.resize(byteCount);
         _port->read(buffer.data(), buffer.size());

src/comm/SerialLink.h

@@ -158,8 +158,6 @@ public:
     bool    disconnect(void);
 
 public slots:
-
-    void readBytes();
     /**
      * @brief Write a number of bytes to the interface.
      *