Enhanced handling of some discoveries states

Author: silvanocerza

arduino/discovery/discoverymanager/discoverymanager.go

@@ -58,6 +58,11 @@ func (dm *DiscoveryManager) Add(disc *discovery.PluggableDiscovery) error {
 // returns the first error it meets or nil
 func (dm *DiscoveryManager) RunAll() error {
 	for _, d := range dm.discoveries {
+		if d.IsAlive() {
+			// This discovery is already running, nothing to do
+			continue
+		}
+
 		if err := d.Run(); err != nil {
 			return err
 		}
@@ -81,6 +86,11 @@ func (dm *DiscoveryManager) StartAll() error {
 func (dm *DiscoveryManager) StartSyncAll() (<-chan *discovery.Event, []error) {
 	errs := []error{}
 	for _, d := range dm.discoveries {
+		if d.IsEventMode() {
+			// Already started, nothing to do
+			continue
+		}
+
 		eventCh := d.EventChannel(5)
 		if err := d.StartSync(); err != nil {
 			errs = append(errs, err)

commands/board/list.go

@@ -273,11 +273,11 @@ func Watch(instanceID int32, interrupt <-chan bool) (<-chan *rpc.BoardListWatchR
 					Error:     boardsError,
 				}
 			case <-interrupt:
-				err := pm.DiscoveryManager().QuitAll()
+				err := pm.DiscoveryManager().StopAll()
 				if err != nil {
 					outChan <- &rpc.BoardListWatchResponse{
 						EventType: "error",
-						Error:     err.Error(),
+						Error:     fmt.Sprintf("stopping discoveries: %s", err),
 					}
 					// Don't close the channel if quitting all discoveries
 					// failed, otherwise some processes might be left running.