Return the KeysDownState from keyboardReport

Also clear out the hidErrorRollOver once sent to reset the keyboard to nothing down.

internal/usbgadget/hid_keyboard.go

@@ -261,7 +261,23 @@ func (u *UsbGadget) keyboardWriteHidFile(modifier byte, keys []byte) error {
 	return nil
 }
 
-func (u *UsbGadget) KeyboardReport(modifier byte, keys []byte) error {
+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 {
+			keys[i] = 0
+		}
+	}
+
+	downState := KeysDownState{
+		Modifier: modifier,
+		Keys:     []byte(keys[:]),
+	}
+	u.updateKeyDownState(downState)
+	return downState
+}
+
+func (u *UsbGadget) KeyboardReport(modifier byte, keys []byte) (KeysDownState, error) {
 	u.keyboardLock.Lock()
 	defer u.keyboardLock.Unlock()
 	defer u.resetUserInputTime()
@@ -273,7 +289,12 @@ func (u *UsbGadget) KeyboardReport(modifier byte, keys []byte) error {
 		keys = append(keys, make([]byte, hidKeyBufferSize-len(keys))...)
 	}
 
-	return u.keyboardWriteHidFile(modifier, keys)
+	err := u.keyboardWriteHidFile(modifier, keys)
+	if err != nil {
+		u.log.Warn().Uint8("modifier", modifier).Uints8("keys", keys).Msg("Could not write keyboard report to hidg0")
+	}
+
+	return u.UpdateKeysDown(modifier, keys), err
 }
 
 const (
@@ -357,16 +378,10 @@ func (u *UsbGadget) KeypressReport(key byte, press bool) (KeysDownState, error)
 		}
 	}
 
-	if err := u.keyboardWriteHidFile(modifier, keys); err != nil {
+	err := u.keyboardWriteHidFile(modifier, keys)
+	if err != nil {
 		u.log.Warn().Uint8("modifier", modifier).Uints8("keys", keys).Msg("Could not write keypress report to hidg0")
 	}
 
-	var result = KeysDownState{
+	return u.UpdateKeysDown(modifier, keys), err
-		Modifier: modifier,
-		Keys:     []byte(keys[:]),
-	}
-
-	u.updateKeyDownState(result)
-
-	return result, nil
 }

jsonrpc.go

@@ -134,7 +134,6 @@ func onRPCMessage(message webrtc.DataChannelMessage, session *Session) {
 		return
 	}
 
-	scopedLogger.Trace().Msg("Calling RPC handler")
 	result, err := callRPCHandler(scopedLogger, handler, request.Params)
 	if err != nil {
 		scopedLogger.Error().Err(err).Msg("Error calling RPC handler")

usb.go

@@ -43,7 +43,7 @@ func initUsbGadget() {
 	}
 }
 
-func rpcKeyboardReport(modifier byte, keys []byte) error {
+func rpcKeyboardReport(modifier byte, keys []byte) (usbgadget.KeysDownState, error) {
 	return gadget.KeyboardReport(modifier, keys)
 }