refactor: enhance keyboard auto-release functionality and key state management

internal/usbgadget/hid_keyboard.go

@@ -158,25 +158,27 @@ func (u *UsbGadget) SetOnKeysDownChange(f func(state KeysDownState)) {
 	u.onKeysDownChange = &f
 }
 
-func (u *UsbGadget) scheduleAutoRelease() {
+func (u *UsbGadget) scheduleAutoRelease(key byte) {
 	u.kbdAutoReleaseLock.Lock()
 	defer unlockWithLog(&u.kbdAutoReleaseLock, u.log, "autoRelease scheduled")
 
-	if u.kbdAutoReleaseTimer != nil {
-		u.kbdAutoReleaseTimer.Stop()
+	if u.kbdAutoReleaseTimers[key] != nil {
+		u.kbdAutoReleaseTimers[key].Stop()
 	}
 
-	u.kbdAutoReleaseTimer = time.AfterFunc(autoReleaseKeyboardInterval, func() {
-		u.performAutoRelease()
+	u.kbdAutoReleaseTimers[key] = time.AfterFunc(autoReleaseKeyboardInterval, func() {
+		u.performAutoRelease(key)
 	})
 }
 
-func (u *UsbGadget) cancelAutoRelease() {
+func (u *UsbGadget) cancelAutoRelease(key byte) {
 	u.kbdAutoReleaseLock.Lock()
 	defer unlockWithLog(&u.kbdAutoReleaseLock, u.log, "autoRelease cancelled")
 
-	if u.kbdAutoReleaseTimer != nil {
-		u.kbdAutoReleaseTimer.Stop()
+	if timer := u.kbdAutoReleaseTimers[key]; timer != nil {
+		timer.Stop()
+		u.kbdAutoReleaseTimers[key] = nil
+		delete(u.kbdAutoReleaseTimers, key)
 	}
 }
 
@@ -184,27 +186,35 @@ func (u *UsbGadget) DelayAutoRelease() {
 	u.kbdAutoReleaseLock.Lock()
 	defer unlockWithLog(&u.kbdAutoReleaseLock, u.log, "autoRelease delayed")
 
-	if u.kbdAutoReleaseTimer == nil {
+	if u.kbdAutoReleaseTimers == nil {
 		return
 	}
 
-	u.kbdAutoReleaseTimer.Reset(autoReleaseKeyboardInterval)
+	for _, timer := range u.kbdAutoReleaseTimers {
+		if timer != nil {
+			timer.Reset(autoReleaseKeyboardInterval)
+		}
+	}
 }
 
-func (u *UsbGadget) performAutoRelease() {
-	select {
-	case <-u.keyboardStateCtx.Done():
-		return
-	default:
-	}
-
+func (u *UsbGadget) performAutoRelease(key byte) {
 	u.kbdAutoReleaseLock.Lock()
 
-	key := u.kbdAutoReleaseLastKey
+	if u.kbdAutoReleaseTimers[key] == nil {
+		u.log.Warn().Uint8("key", key).Msg("autoRelease timer not found")
+		u.kbdAutoReleaseLock.Unlock()
+		return
+	}
+
+	u.kbdAutoReleaseTimers[key].Stop()
+	u.kbdAutoReleaseTimers[key] = nil
+	delete(u.kbdAutoReleaseTimers, key)
+	u.kbdAutoReleaseLock.Unlock()
 
 	// Skip if already released
 	state := u.GetKeysDownState()
 	alreadyReleased := true
+
 	for i := range state.Keys {
 		if state.Keys[i] == key {
 			alreadyReleased = false
@@ -216,10 +226,7 @@ func (u *UsbGadget) performAutoRelease() {
 		return
 	}
 
-	u.kbdAutoReleaseTimer = nil
-	u.kbdAutoReleaseLock.Unlock()
-
-	u.keypressReport(key, false) // autoRelease the ket
+	u.keypressReport(key, false)
 }
 
 func (u *UsbGadget) listenKeyboardEvents() {
@@ -311,7 +318,7 @@ func (u *UsbGadget) keyboardWriteHidFile(modifier byte, keys []byte) error {
 	return nil
 }
 
-func (u *UsbGadget) UpdateKeysDown(modifier byte, keys []byte) {
+func (u *UsbGadget) UpdateKeysDown(modifier byte, keys []byte) KeysDownState {
 	// if we just reported an error roll over, we should clear the keys
 	if keys[0] == hidErrorRollOver {
 		for i := range keys {
@@ -329,7 +336,7 @@ func (u *UsbGadget) UpdateKeysDown(modifier byte, keys []byte) {
 	if u.keysDownState.Modifier == state.Modifier &&
 		bytes.Equal(u.keysDownState.Keys, state.Keys) {
 		u.keyboardStateLock.Unlock()
-		return // No change in key down state
+		return state // No change in key down state
 	}
 
 	u.keysDownState = state
@@ -338,7 +345,7 @@ func (u *UsbGadget) UpdateKeysDown(modifier byte, keys []byte) {
 	if u.onKeysDownChange != nil {
 		(*u.onKeysDownChange)(state) // this enques to the outgoing hidrpc queue via usb.go → currentSession.enqueueKeysDownState(...)
 	}
-	return
+	return state
 }
 
 func (u *UsbGadget) KeyboardReport(modifier byte, keys []byte) error {
@@ -397,7 +404,7 @@ var KeyCodeToMaskMap = map[byte]byte{
 	RightSuper:   ModifierMaskRightSuper,
 }
 
-func (u *UsbGadget) keypressReport(key byte, press bool) error {
+func (u *UsbGadget) keypressReport(key byte, press bool) (KeysDownState, error) {
 	defer u.resetUserInputTime()
 
 	l := u.log.With().Uint8("key", key).Bool("press", press).Logger()
@@ -466,21 +473,20 @@ func (u *UsbGadget) keypressReport(key byte, press bool) error {
 	}
 
 	err := u.keyboardWriteHidFile(modifier, keys)
-	u.UpdateKeysDown(modifier, keys)
-	return err
+	return u.UpdateKeysDown(modifier, keys), err
 }
 
 func (u *UsbGadget) KeypressReport(key byte, press bool) error {
-	u.kbdAutoReleaseLock.Lock()
-	u.kbdAutoReleaseLastKey = key
-	u.kbdAutoReleaseLock.Unlock()
+	state, err := u.keypressReport(key, press)
+	isRolledOver := state.Keys[0] == hidErrorRollOver
 
-	if press {
-		u.scheduleAutoRelease()
+	if isRolledOver {
+		u.cancelAutoRelease(key)
+	} else if press {
+		u.scheduleAutoRelease(key)
 	} else {
-		u.cancelAutoRelease()
+		u.cancelAutoRelease(key)
 	}
 
-	err := u.keypressReport(key, press)
 	return err
 }

internal/usbgadget/usbgadget.go

@@ -68,9 +68,8 @@ type UsbGadget struct {
 	keyboardState byte          // keyboard latched state (NumLock, CapsLock, ScrollLock, Compose, Kana)
 	keysDownState KeysDownState // keyboard dynamic state (modifier keys and pressed keys)
 
-	kbdAutoReleaseLock    sync.Mutex
-	kbdAutoReleaseTimer   *time.Timer
-	kbdAutoReleaseLastKey byte
+	kbdAutoReleaseLock   sync.Mutex
+	kbdAutoReleaseTimers map[byte]*time.Timer
 
 	keyboardStateLock   sync.Mutex
 	keyboardStateCtx    context.Context
@@ -122,23 +121,24 @@ func newUsbGadget(name string, configMap map[string]gadgetConfigItem, enabledDev
 	keyboardCtx, keyboardCancel := context.WithCancel(context.Background())
 
 	g := &UsbGadget{
-		name:                name,
-		kvmGadgetPath:       path.Join(gadgetPath, name),
-		configC1Path:        path.Join(gadgetPath, name, "configs/c.1"),
-		configMap:           configMap,
-		customConfig:        *config,
-		configLock:          sync.Mutex{},
-		keyboardLock:        sync.Mutex{},
-		absMouseLock:        sync.Mutex{},
-		relMouseLock:        sync.Mutex{},
-		txLock:              sync.Mutex{},
-		keyboardStateCtx:    keyboardCtx,
-		keyboardStateCancel: keyboardCancel,
-		keyboardState:       0,
-		keysDownState:       KeysDownState{Modifier: 0, Keys: []byte{0, 0, 0, 0, 0, 0}}, // must be initialized to hidKeyBufferSize (6) zero bytes
-		enabledDevices:      *enabledDevices,
-		lastUserInput:       time.Now(),
-		log:                 logger,
+		name:                 name,
+		kvmGadgetPath:        path.Join(gadgetPath, name),
+		configC1Path:         path.Join(gadgetPath, name, "configs/c.1"),
+		configMap:            configMap,
+		customConfig:         *config,
+		configLock:           sync.Mutex{},
+		keyboardLock:         sync.Mutex{},
+		absMouseLock:         sync.Mutex{},
+		relMouseLock:         sync.Mutex{},
+		txLock:               sync.Mutex{},
+		keyboardStateCtx:     keyboardCtx,
+		keyboardStateCancel:  keyboardCancel,
+		keyboardState:        0,
+		keysDownState:        KeysDownState{Modifier: 0, Keys: []byte{0, 0, 0, 0, 0, 0}}, // must be initialized to hidKeyBufferSize (6) zero bytes
+		kbdAutoReleaseTimers: make(map[byte]*time.Timer),
+		enabledDevices:       *enabledDevices,
+		lastUserInput:        time.Now(),
+		log:                  logger,
 
 		strictMode: config.strictMode,
 
@@ -163,10 +163,10 @@ func (u *UsbGadget) Close() error {
 
 	// Stop auto-release timer
 	u.kbdAutoReleaseLock.Lock()
-	if u.kbdAutoReleaseTimer != nil {
-		u.kbdAutoReleaseTimer.Stop()
-		u.kbdAutoReleaseTimer = nil
+	for _, timer := range u.kbdAutoReleaseTimers {
+		timer.Stop()
 	}
+	u.kbdAutoReleaseTimers = make(map[byte]*time.Timer)
 	u.kbdAutoReleaseLock.Unlock()
 
 	// Close HID files

ui/src/components/popovers/PasteModal.tsx

@@ -40,7 +40,7 @@ export default function PasteModal() {
   const delayClassName = useMemo(() => debugMode ? "" : "hidden", [debugMode]);
 
   const { setKeyboardLayout } = useSettingsStore();
-  const { selectedKeyboard } = useKeyboardLayout();
+  const { selectedKeyboard }  = useKeyboardLayout();
 
   useEffect(() => {
     send("getKeyboardLayout", {}, (resp: JsonRpcResponse) => {