SSH: Don't use socket if it's in an unhealthy state.

src/plugins/coreplugin/ssh/sshconnection.cpp

@@ -241,6 +241,8 @@ void SshConnectionPrivate::handleIncomingData()
         return; // For stuff queued in the event loop after we've called closeConnection();
 
     try {
+        if (!canUseSocket())
+            return;
         m_incomingData += m_socket->readAll();
 #ifdef CREATOR_SSH_DEBUG
         qDebug("state = %d, remote data size = %d", m_state,
@@ -478,7 +480,8 @@ void SshConnectionPrivate::handleDisconnect()
 
 void SshConnectionPrivate::sendData(const QByteArray &data)
 {
-    m_socket->write(data);
+    if (canUseSocket())
+        m_socket->write(data);
 }
 
 void SshConnectionPrivate::handleSocketDisconnected()
@@ -543,10 +546,17 @@ void SshConnectionPrivate::closeConnection(SshErrorCode sshError,
         emit error(userError);
     if (m_state == ConnectionEstablished)
         emit disconnected();
-    m_socket->disconnectFromHost();
+    if (canUseSocket())
+        m_socket->disconnectFromHost();
     m_state = SocketUnconnected;
 }
 
+bool SshConnectionPrivate::canUseSocket() const
+{
+    return m_socket->isValid()
+        && m_socket->state() == QAbstractSocket::ConnectedState;
+}
+
 QSharedPointer<SshRemoteProcess> SshConnectionPrivate::createRemoteProcess(const QByteArray &command)
 {
     return m_channelManager->createRemoteProcess(command);

src/plugins/coreplugin/ssh/sshconnection_p.h

@@ -124,6 +124,7 @@ private:
     void handleChannelEof();
     void handleChannelClose();
     void handleDisconnect();
+    bool canUseSocket() const;
 
     void sendData(const QByteArray &data);
 

src/plugins/coreplugin/ssh/sshsendfacility.cpp

@@ -48,8 +48,11 @@ void SshSendFacility::sendPacket()
 #ifdef CREATOR_SSH_DEBUG
     qDebug("Sending packet, client seq nr is %u", m_clientSeqNr);
 #endif
-    m_socket->write(m_outgoingPacket.rawData());
+    if (m_socket->isValid()
-    ++m_clientSeqNr;
+        && m_socket->state() == QAbstractSocket::ConnectedState) {
+        m_socket->write(m_outgoingPacket.rawData());
+        ++m_clientSeqNr;
+    }
 }
 
 void SshSendFacility::reset()