fix dead lock

makefile

@@ -1,5 +1,5 @@
 debug:
-	go run -tags "debug" ./...
+	go run -tags "debug" -race ./...
 
 all: clean build
 

runtime.go

@@ -51,6 +51,7 @@ func run(ctx context.Context, debug bool) int {
 
 	if err := docker.StartWatcher(ctx, config.DaemonConfiguration.PullInterval); err != nil {
 		slog.Error("unable to start the docker watcher", "thread", "main", "err", err)
+		return failure
 	}
 
 	el, err := runtime.NewEventLoop(ctx, docker)
@@ -61,6 +62,7 @@ func run(ctx context.Context, debug bool) int {
 	defer el.Close()
 
 	go func() {
+		interruptNum := 0
 		c := make(chan os.Signal, 10)
 		signal.Notify(c)
 		defer close(c)
@@ -69,16 +71,21 @@ func run(ctx context.Context, debug bool) int {
 			switch sig {
 			case os.Interrupt:
 				{
+					interruptNum++
 					slog.Info("the process received an interruption signal", "thread", "signal_watcher", "signal", sig.String())
 					el.Close()
 				}
 			case os.Kill:
 				{
+					interruptNum++
 					slog.Info("the process received a kill signal", "thread", "signal_watcher", "signal", sig.String())
 					el.Close()
 				}
 			}
-
+			if interruptNum == 3 {
+				slog.Info("received 3 times a stop signal, forcing the program to shut down", "thread", "signal_watch")
+				os.Exit(failure)
+			}
 		}
 	}()
 

runtime/runtime.go

@@ -21,18 +21,22 @@ type (
 		executors map[string]cron.EntryID
 
 		ctx          context.Context
-		eventMu      sync.Mutex
+		cancelFunc   context.CancelFunc
+		eventMu      sync.RWMutex
 		eventBuffer  []helper.ContainerEvent
 		eventTrigger chan struct{}
 	}
 )
 
 func NewEventLoop(ctx context.Context, docker *helper.DockerHelper) (*EventLoop, error) {
+	loopCtx, cancelFunc := context.WithCancel(contextutil.WithThreadName(context.Background(), "event_loop"))
 	loop := &EventLoop{
 		docker:       docker,
 		cr:           cron.New(),
-		ctx:       contextutil.WithThreadName(context.Background(), "event_loop"),
+		ctx:          loopCtx,
+		cancelFunc:   cancelFunc,
 		executors:    make(map[string]cron.EntryID),
+		eventTrigger: make(chan struct{}),
 	}
 
 	if err := loop.firstRun(ctx); err != nil {
@@ -46,6 +50,7 @@ func NewEventLoop(ctx context.Context, docker *helper.DockerHelper) (*EventLoop,
 }
 
 func (el *EventLoop) Close() error {
+	el.cancelFunc()
 	ctx := el.cr.Stop()
 	<-ctx.Done()
 	return nil
@@ -146,15 +151,33 @@ func (el *EventLoop) unregister(container helper.Container) {
 
 func (el *EventLoop) startEventLoop() {
 	for {
-		if len(el.eventBuffer) == 0 {
-			<-el.eventTrigger
+		el.eventMu.RLock()
+		eventBufferLen := len(el.eventBuffer)
+		el.eventMu.RUnlock()
+
+		if eventBufferLen == 0 {
+			select {
+			case <-el.eventTrigger:
+				{
+					slog.Debug("event loop waken up", "thread", contextutil.ThreadName(el.ctx))
+				}
+			case <-el.ctx.Done():
+				{
+					return
+				}
+			}
 		}
 
+		var ev helper.ContainerEvent
 		el.eventMu.Lock()
-		ev := el.eventBuffer[0]
-		el.eventBuffer = append([]helper.ContainerEvent{}, el.eventBuffer[1:]...)
+		if len(el.eventBuffer) == 0 {
+			el.eventMu.Unlock()
+			continue
+		}
+		ev, el.eventBuffer = el.eventBuffer[0], el.eventBuffer[1:]
 		el.eventMu.Unlock()
 
+		slog.Debug("processing docker event", "thread", contextutil.ThreadName(el.ctx))
 		el.process(ev)
 	}
 }