CmdBridge: Fix deadlock

The watch mutex was held indefinitely since the "defer" is only
called once the parent function exits. Moving the event handling
into its own function solves the issue.

Also removed unused function "processRemove"

Change-Id: I66598d1ba0fb66622ca97531f9ee13272ce63f50
Reviewed-by: hjk <hjk@qt.io>

src/libs/gocmdbridge/server/watcher.go

@@ -35,13 +35,7 @@ type watchevent struct {
 	EventType int
 }
 
-func (watchHandler *WatcherHandler) start(out chan<- []byte) {
-	for {
-		select {
-		case event, ok := <-watchHandler.watcher.Events:
-			if !ok {
-				return
-			}
+func handleEvent(event fsnotify.Event, watchHandler *WatcherHandler, out chan<- []byte) {
 	watchHandler.mutex.Lock()
 	defer watchHandler.mutex.Unlock()
 
@@ -69,6 +63,16 @@ func (watchHandler *WatcherHandler) start(out chan<- []byte) {
 			out <- data
 		}
 	}
+}
+
+func (watchHandler *WatcherHandler) start(out chan<- []byte) {
+	for {
+		select {
+		case event, ok := <-watchHandler.watcher.Events:
+			if !ok {
+				return
+			}
+			handleEvent(event, watchHandler, out)
 		case err, ok := <-watchHandler.watcher.Errors:
 			if !ok {
 				return
@@ -151,29 +155,3 @@ type watchnotfounderror struct {
 func (e *watchnotfounderror) Error() string {
 	return "Watch not found"
 }
-
-func (watchHandler *WatcherHandler) processRemove(cmd command, out chan<- []byte) {
-	watchHandler.mutex.Lock()
-	defer watchHandler.mutex.Unlock()
-
-	if _, ok := watchHandler.watchList[cmd.Id]; !ok {
-		sendError(out, cmd, &watchnotfounderror{})
-		return
-	}
-	watchHandler.watchRefs[cmd.Path]--
-	if watchHandler.watchRefs[cmd.Path] == 0 {
-		err := watchHandler.watcher.Remove(cmd.Path)
-		if err != nil {
-			sendError(out, cmd, err)
-			return
-		}
-	}
-	delete(watchHandler.watchList, cmd.Id)
-
-	data, _ := cbor.Marshal(removewatchresult{
-		Type:   "removewatchresult",
-		Id:     cmd.Id,
-		Result: true,
-	})
-	out <- data
-}