feat: simplify failsafe mode for native proxy

failsafe.go

@@ -77,10 +77,12 @@ func checkFailsafeReason() {
 		_ = os.Remove(lastCrashPath)
 
 		// TODO: read the goroutine stack trace and check which goroutine is panicking
+		failsafeModeActive = true
 		if strings.Contains(failsafeCrashLog, "runtime.cgocall") {
-			failsafeModeActive = true
 			failsafeModeReason = "video"
 			return
+		} else {
+			failsafeModeReason = "unknown"
 		}
 	})
 }

internal/native/cgo_linux.go

@@ -50,17 +50,9 @@ static inline void jetkvm_cgo_setup_rpc_handler() {
 import "C"
 
 var (
-	cgoLock     sync.Mutex
-	cgoDisabled bool
+	cgoLock sync.Mutex
 )
 
-func setCgoDisabled(disabled bool) {
-	cgoLock.Lock()
-	defer cgoLock.Unlock()
-
-	cgoDisabled = disabled
-}
-
 //export jetkvm_go_video_state_handler
 func jetkvm_go_video_state_handler(state *C.jetkvm_video_state_t) {
 	videoState := VideoState{
@@ -104,10 +96,6 @@ func jetkvm_go_rpc_handler(method *C.cchar_t, params *C.cchar_t) {
 var eventCodeToNameMap = map[int]string{}
 
 func uiEventCodeToName(code int) string {
-	if cgoDisabled {
-		return ""
-	}
-
 	name, ok := eventCodeToNameMap[code]
 	if !ok {
 		cCode := C.int(code)
@@ -120,10 +108,6 @@ func uiEventCodeToName(code int) string {
 }
 
 func setUpNativeHandlers() {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -135,10 +119,6 @@ func setUpNativeHandlers() {
 }
 
 func uiInit(rotation uint16) {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -148,10 +128,6 @@ func uiInit(rotation uint16) {
 }
 
 func uiTick() {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -159,10 +135,6 @@ func uiTick() {
 }
 
 func videoInit(factor float64) error {
-	if cgoDisabled {
-		return nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -176,10 +148,6 @@ func videoInit(factor float64) error {
 }
 
 func videoShutdown() {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -187,10 +155,6 @@ func videoShutdown() {
 }
 
 func videoStart() {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -198,10 +162,6 @@ func videoStart() {
 }
 
 func videoStop() {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -209,10 +169,6 @@ func videoStop() {
 }
 
 func videoLogStatus() string {
-	if cgoDisabled {
-		return ""
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -223,10 +179,6 @@ func videoLogStatus() string {
 }
 
 func uiSetVar(name string, value string) {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -240,10 +192,6 @@ func uiSetVar(name string, value string) {
 }
 
 func uiGetVar(name string) string {
-	if cgoDisabled {
-		return ""
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -254,10 +202,6 @@ func uiGetVar(name string) string {
 }
 
 func uiSwitchToScreen(screen string) {
-	if cgoDisabled {
-		return
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -267,10 +211,6 @@ func uiSwitchToScreen(screen string) {
 }
 
 func uiGetCurrentScreen() string {
-	if cgoDisabled {
-		return ""
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -279,10 +219,6 @@ func uiGetCurrentScreen() string {
 }
 
 func uiObjAddState(objName string, state string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -295,10 +231,6 @@ func uiObjAddState(objName string, state string) (bool, error) {
 }
 
 func uiObjClearState(objName string, state string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -311,10 +243,6 @@ func uiObjClearState(objName string, state string) (bool, error) {
 }
 
 func uiGetLVGLVersion() string {
-	if cgoDisabled {
-		return ""
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -323,10 +251,6 @@ func uiGetLVGLVersion() string {
 
 // TODO: use Enum instead of string but it's not a hot path and performance is not a concern now
 func uiObjAddFlag(objName string, flag string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -339,10 +263,6 @@ func uiObjAddFlag(objName string, flag string) (bool, error) {
 }
 
 func uiObjClearFlag(objName string, flag string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -363,10 +283,6 @@ func uiObjShow(objName string) (bool, error) {
 }
 
 func uiObjSetOpacity(objName string, opacity int) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -378,10 +294,6 @@ func uiObjSetOpacity(objName string, opacity int) (bool, error) {
 }
 
 func uiObjFadeIn(objName string, duration uint32) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -394,10 +306,6 @@ func uiObjFadeIn(objName string, duration uint32) (bool, error) {
 }
 
 func uiObjFadeOut(objName string, duration uint32) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -410,10 +318,6 @@ func uiObjFadeOut(objName string, duration uint32) (bool, error) {
 }
 
 func uiLabelSetText(objName string, text string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -431,10 +335,6 @@ func uiLabelSetText(objName string, text string) (bool, error) {
 }
 
 func uiImgSetSrc(objName string, src string) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -450,10 +350,6 @@ func uiImgSetSrc(objName string, src string) (bool, error) {
 }
 
 func uiDispSetRotation(rotation uint16) (bool, error) {
-	if cgoDisabled {
-		return false, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -466,10 +362,6 @@ func uiDispSetRotation(rotation uint16) (bool, error) {
 }
 
 func videoGetStreamQualityFactor() (float64, error) {
-	if cgoDisabled {
-		return 0, nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -478,10 +370,6 @@ func videoGetStreamQualityFactor() (float64, error) {
 }
 
 func videoSetStreamQualityFactor(factor float64) error {
-	if cgoDisabled {
-		return nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -490,10 +378,6 @@ func videoSetStreamQualityFactor(factor float64) error {
 }
 
 func videoGetEDID() (string, error) {
-	if cgoDisabled {
-		return "", nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 
@@ -502,10 +386,6 @@ func videoGetEDID() (string, error) {
 }
 
 func videoSetEDID(edid string) error {
-	if cgoDisabled {
-		return nil
-	}
-
 	cgoLock.Lock()
 	defer cgoLock.Unlock()
 

internal/native/empty.go

@@ -0,0 +1,111 @@
+package native
+
+type EmptyNativeInterface struct {
+}
+
+func (e *EmptyNativeInterface) Start() error { return nil }
+
+func (e *EmptyNativeInterface) VideoSetSleepMode(enabled bool) error { return nil }
+
+func (e *EmptyNativeInterface) VideoGetSleepMode() (bool, error) { return false, nil }
+
+func (e *EmptyNativeInterface) VideoSleepModeSupported() bool {
+	return false
+}
+
+func (e *EmptyNativeInterface) VideoSetQualityFactor(factor float64) error {
+	return nil
+}
+
+func (e *EmptyNativeInterface) VideoGetQualityFactor() (float64, error) {
+	return 0, nil
+}
+
+func (e *EmptyNativeInterface) VideoSetEDID(edid string) error {
+	return nil
+}
+
+func (e *EmptyNativeInterface) VideoGetEDID() (string, error) {
+	return "", nil
+}
+
+func (e *EmptyNativeInterface) VideoLogStatus() (string, error) {
+	return "", nil
+}
+
+func (e *EmptyNativeInterface) VideoStop() error {
+	return nil
+}
+
+func (e *EmptyNativeInterface) VideoStart() error {
+	return nil
+}
+
+func (e *EmptyNativeInterface) GetLVGLVersion() (string, error) {
+	return "", nil
+}
+
+func (e *EmptyNativeInterface) UIObjHide(objName string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjShow(objName string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UISetVar(name string, value string) {
+}
+
+func (e *EmptyNativeInterface) UIGetVar(name string) string {
+	return ""
+}
+
+func (e *EmptyNativeInterface) UIObjAddState(objName string, state string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjClearState(objName string, state string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjAddFlag(objName string, flag string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjClearFlag(objName string, flag string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjSetOpacity(objName string, opacity int) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjFadeIn(objName string, duration uint32) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjFadeOut(objName string, duration uint32) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjSetLabelText(objName string, text string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UIObjSetImageSrc(objName string, image string) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) DisplaySetRotation(rotation uint16) (bool, error) {
+	return false, nil
+}
+
+func (e *EmptyNativeInterface) UpdateLabelIfChanged(objName string, newText string) {}
+
+func (e *EmptyNativeInterface) UpdateLabelAndChangeVisibility(objName string, newText string) {}
+
+func (e *EmptyNativeInterface) SwitchToScreenIf(screenName string, shouldSwitch []string) {}
+
+func (e *EmptyNativeInterface) SwitchToScreenIfDifferent(screenName string) {}
+
+func (e *EmptyNativeInterface) DoNotUseThisIsForCrashTestingOnly() {}

internal/native/grpc_client.go

@@ -131,7 +131,7 @@ func (c *GRPCClient) startEventStream() {
 		stream, err := c.client.StreamEvents(ctx, &pb.Empty{})
 		if err != nil {
 			c.logger.Warn().Err(err).Msg("failed to start event stream, retrying ...")
-			time.Sleep(1 * time.Second)
+			time.Sleep(5 * time.Second)
 			continue
 		}
 

internal/native/native.go

@@ -9,7 +9,6 @@ import (
 )
 
 type Native struct {
-	disable              bool
 	ready                chan struct{}
 	l                    *zerolog.Logger
 	lD                   *zerolog.Logger
@@ -28,7 +27,6 @@ type Native struct {
 }
 
 type NativeOptions struct {
-	Disable              bool
 	SystemVersion        *semver.Version
 	AppVersion           *semver.Version
 	DisplayRotation      uint16
@@ -81,7 +79,6 @@ func NewNative(opts NativeOptions) *Native {
 	}
 
 	return &Native{
-		disable:              opts.Disable,
 		ready:                make(chan struct{}),
 		l:                    &nativeSubLogger,
 		lD:                   &displaySubLogger,
@@ -100,12 +97,6 @@ func NewNative(opts NativeOptions) *Native {
 }
 
 func (n *Native) Start() error {
-	if n.disable {
-		nativeLogger.Warn().Msg("native is disabled, skipping initialization")
-		setCgoDisabled(true)
-		return nil
-	}
-
 	// set up singleton
 	setInstance(n)
 	setUpNativeHandlers()

internal/native/proxy.go

@@ -61,7 +61,6 @@ func (n *NativeOptions) toProxyOptions() *nativeProxyOptions {
 		maxRestartAttempts = n.MaxRestartAttempts
 	}
 	return &nativeProxyOptions{
-		Disable:              n.Disable,
 		SystemVersion:        n.SystemVersion,
 		AppVersion:           n.AppVersion,
 		DisplayRotation:      n.DisplayRotation,
@@ -78,7 +77,6 @@ func (n *NativeOptions) toProxyOptions() *nativeProxyOptions {
 
 func (p *nativeProxyOptions) toNativeOptions() *NativeOptions {
 	return &NativeOptions{
-		Disable:              p.Disable,
 		SystemVersion:        p.SystemVersion,
 		AppVersion:           p.AppVersion,
 		DisplayRotation:      p.DisplayRotation,
@@ -135,7 +133,6 @@ type NativeProxy struct {
 // NewNativeProxy creates a new NativeProxy that spawns a separate process
 func NewNativeProxy(opts NativeOptions) (*NativeProxy, error) {
 	proxyOptions := opts.toProxyOptions()
-	proxyOptions.CtrlUnixSocket = fmt.Sprintf("jetkvm/native/grpc/%s", randomId(4))
 	proxyOptions.VideoStreamUnixSocket = fmt.Sprintf("@jetkvm/native/video-stream/%s", randomId(4))
 
 	// Get the current executable path to spawn itself
@@ -211,6 +208,12 @@ func (w *nativeProxyStdoutHandler) Write(p []byte) (n int, err error) {
 }
 
 func (p *NativeProxy) toProcessCommand() (*cmdWrapper, error) {
+	// generate a new random ID for the gRPC socket on each restart
+	// sometimes the socket is not closed properly when the process exits
+	// this is a workaround to avoid the issue
+	p.nativeUnixSocket = fmt.Sprintf("jetkvm/native/grpc/%s", randomId(4))
+	p.options.CtrlUnixSocket = p.nativeUnixSocket
+
 	envArgs, err := utils.MarshalEnv(p.options)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal environment variables: %w", err)
@@ -407,7 +410,10 @@ func (p *NativeProxy) restartProcess() error {
 
 	// Close old client
 	if p.client != nil {
-		_ = p.client.Close()
+		if err := p.client.Close(); err != nil {
+			p.logger.Warn().Err(err).Msg("failed to close gRPC client")
+		}
+		p.client = nil // set to nil to avoid closing it again
 	}
 
 	p.restarts++

internal/native/server.go

@@ -85,6 +85,19 @@ func RunNativeProcess(binaryName string) {
 		logger.Fatal().Err(err).Msg("failed to write handshake message to stdout")
 	}
 
+	go func() {
+		sigChan := make(chan os.Signal, 1)
+		signal.Notify(sigChan, syscall.SIGHUP)
+
+		// non-blocking receive
+		select {
+		case <-sigChan:
+			logger.Info().Msg("received SIGHUP signal, emulating crash")
+			nativeInstance.DoNotUseThisIsForCrashTestingOnly()
+		default:
+		}
+	}()
+
 	// Set up signal handling
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, syscall.SIGTERM, syscall.SIGINT)

native.go

@@ -16,10 +16,15 @@ var (
 )
 
 func initNative(systemVersion *semver.Version, appVersion *semver.Version) {
+	if failsafeModeActive {
+		nativeInstance = &native.EmptyNativeInterface{}
+		nativeLogger.Warn().Msg("failsafe mode active, using empty native interface")
+		return
+	}
+
 	nativeLogger.Info().Msg("initializing native proxy")
 	var err error
 	nativeInstance, err = native.NewNativeProxy(native.NativeOptions{
-		Disable:              failsafeModeActive,
 		SystemVersion:        systemVersion,
 		AppVersion:           appVersion,
 		DisplayRotation:      config.GetDisplayRotation(),