Merge pull request #112 from BallAerospace/protect_interface_thread_s…

…top_from_autoconnect

closes #111. Protect InterfaceThread Stop from Auto Reconnect

lib/cosmos/tools/cmd_tlm_server/connections.rb

@@ -81,7 +81,6 @@ def disconnect(connection_name)
       connection = @connections[connection_name.upcase]
       raise "Unknown #{@keyword}: #{connection_name}" unless connection
 
-      connection.disconnect
       stop_thread(connection)
       Logger.info "Disconnected from #{@keyword} #{connection_name.upcase}"
     end

lib/cosmos/tools/cmd_tlm_server/gui/interfaces_tab.rb

@@ -50,15 +50,20 @@ def update(name)
       interfaces.all.each do |interface_name, interface|
         button = @interfaces_table[name].cellWidget(row,1)
         state = @interfaces_table[name].item(row,2)
-        if interface.connected?
+        if interface.connected? and interface.thread
           button.setText('Disconnect')
           button.setDisabled(true) if interface.disable_disconnect
           state.setText('true')
           state.textColor = Cosmos::GREEN
         elsif interface.thread
           button.text = 'Cancel Connect'
           button.setDisabled(false)
-          state.text = 'attempting'
+          state.setText('attempting')
+          state.textColor = Cosmos::RED
+        elsif interface.connected?
+          button.setText('Error')
+          button.setDisabled(false)
+          state.setText('error')
           state.textColor = Cosmos::RED
         else
           button.setText('Connect')
@@ -137,12 +142,14 @@ def populate_interface_table(name, interfaces, interfaces_table)
     end
 
     def create_button(name, interface, interface_name)
-      if interface.connected?
+      if interface.connected? and interface.thread
         button_text = 'Disconnect'
-      elsif interface.thread.nil?
-        button_text = 'Connect'
-      else
+      elsif interface.thread
         button_text = 'Cancel Connect'
+      elsif interface.connected?
+        button_text = 'Error'
+      else
+        button_text = 'Connect'
       end
       button = Qt::PushButton.new(button_text)
       if name == ROUTERS
@@ -172,12 +179,15 @@ def create_button(name, interface, interface_name)
 
     def create_state(interface)
       state = Qt::TableWidgetItem.new
-      if interface.connected?
+      if interface.connected? and interface.thread
         state.setText('true')
         state.textColor = Cosmos::GREEN
       elsif interface.thread
         state.setText('attempting')
         state.textColor = Cosmos::YELLOW
+      elsif interface.connected?
+        state.setText('error')
+        state.textColor = Cosmos::RED
       else
         state.setText('false')
         state.textColor = Cosmos::BLACK

lib/cosmos/tools/cmd_tlm_server/interface_thread.rb

@@ -46,6 +46,7 @@ def initialize(interface)
       @thread_sleeper = Sleeper.new
       @connection_failed_messages = []
       @connection_lost_messages = []
+      @mutex = Mutex.new
     end
 
     # Create and start the Ruby thread that will encapsulate the interface.
@@ -58,9 +59,14 @@ def start
         begin
           Logger.info "Starting packet reading for #{@interface.name}"
           while true
+            break if @cancel_thread
             unless @interface.connected?
               begin
-                connect()
+                @mutex.synchronize do
+                  # We need to make sure connect is not called after stop() has been called
+                  connect() unless @cancel_thread
+                end
+                break if @cancel_thread
               rescue Exception => connect_error
                 handle_connection_failed(connect_error)
                 if @cancel_thread
@@ -102,14 +108,19 @@ def start
             Cosmos.handle_fatal_exception(error)
           end
         end
+        Logger.info "Stopped packet reading for #{@interface.name}"
       end  # Thread.new
     end # def start
 
     # Disconnect from the interface and stop the thread
     def stop
-      @cancel_thread = true
-      @thread_sleeper.cancel
-      @interface.disconnect
+      @mutex.synchronize do
+        # Need to make sure that @cancel_thread is set and the interface disconnected within
+        # mutex to ensure that connect() is not called when we want to stop()
+        @cancel_thread = true
+        @thread_sleeper.cancel
+        @interface.disconnect
+      end
       Cosmos.kill_thread(self, @thread) if @thread != Thread.current
     end