fix(display): reset display state after native binary is restarted (jetkvm#654)

* fix(usbgadget): add lock for logWithSupression

* fix(display): reset display state after native binary is restarted

Author: ym

display.go

@@ -9,9 +9,14 @@ import (
 	"time"
 )
 
-var currentScreen = "ui_Boot_Screen"
 var backlightState = 0 // 0 - NORMAL, 1 - DIMMED, 2 - OFF
 
+var (
+	currentScreen   = "ui_Boot_Screen"
+	displayedTexts  = make(map[string]string)
+	screenStateLock = sync.Mutex{}
+)
+
 var (
 	dimTicker *time.Ticker
 	offTicker *time.Ticker
@@ -22,6 +27,8 @@ const (
 	backlightControlClass string = "/sys/class/backlight/backlight/brightness"
 )
 
+// do not call this function directly, use switchToScreenIfDifferent instead
+// this function is not thread safe
 func switchToScreen(screen string) {
 	_, err := CallCtrlAction("lv_scr_load", map[string]interface{}{"obj": screen})
 	if err != nil {
@@ -31,8 +38,6 @@ func switchToScreen(screen string) {
 	currentScreen = screen
 }
 
-var displayedTexts = make(map[string]string)
-
 func lvObjSetState(objName string, state string) (*CtrlResponse, error) {
 	return CallCtrlAction("lv_obj_set_state", map[string]interface{}{"obj": objName, "state": state})
 }
@@ -78,19 +83,33 @@ func lvDispSetRotation(rotation string) (*CtrlResponse, error) {
 }
 
 func updateLabelIfChanged(objName string, newText string) {
+	screenStateLock.Lock()
+	defer screenStateLock.Unlock()
+
 	if newText != "" && newText != displayedTexts[objName] {
 		_, _ = lvLabelSetText(objName, newText)
 		displayedTexts[objName] = newText
 	}
 }
 
 func switchToScreenIfDifferent(screenName string) {
+	screenStateLock.Lock()
+	defer screenStateLock.Unlock()
+
 	if currentScreen != screenName {
 		displayLogger.Info().Str("from", currentScreen).Str("to", screenName).Msg("switching screen")
 		switchToScreen(screenName)
 	}
 }
 
+func clearDisplayState() {
+	screenStateLock.Lock()
+	defer screenStateLock.Unlock()
+
+	displayedTexts = make(map[string]string)
+	currentScreen = "ui_Boot_Screen"
+}
+
 var (
 	cloudBlinkLock    sync.Mutex = sync.Mutex{}
 	cloudBlinkStopped bool

native.go

@@ -272,6 +272,13 @@ func restartNativeBinary(binaryPath string) error {
 		nativeLogger.Warn().Err(err).Msg("failed to restart binary")
 	}
 	nativeCmd = cmd
+
+	// reset the display state
+	time.Sleep(1 * time.Second)
+	clearDisplayState()
+	updateStaticContents()
+	requestDisplayUpdate(true)
+
 	return err
 }