fix(runtime): make Xray core recovery work, and stop it leaking a core per try

Core recovery could never succeed, and every attempt left a live
libxray.so behind.

startCore() calls startTimer(), which builds a CountDownTimer and so a
Handler on the calling thread. handleXrayCoreExit() runs recovery on a
bare Thread, so the constructor threw "Can't create handler inside
thread ... that has not called Looper.prepare()" and took the whole
restart down with it. The catch then deleted the ephemeral config and
returned false without killing the process pb.start() had already
started, so each retry stranded another core.

Measured on an emulator by killing the live core:

  before  1 -> 5 -> 6 -> 8 processes over 120 s, never recovers
  after   "Xray core recovered without dropping TUN" on attempt 1,
          exactly 1 process

startTimer now posts to the main looper, re-checking RUNTIME_TOKEN
inside the post so a stop that lands while it is queued cannot leave a
timer running for a dead generation. stopTimer posts too, so the
countDownTimer field is only touched from one thread. The catch clears
xrayProcess before destroying it, so the monitor thread's
`xrayProcess === process` guard fails and recovery is not re-entered
for a core being killed here.

Pre-existing on main; reachable whenever the core exits.

Co-Authored-By: Claude Opus 5 <[email protected]>

local_packages/flutter_vless_android-1.1.5/android/src/main/kotlin/com/github/tfox/flutter_vless/xray/core/XrayCoreManager.kt

@@ -11,6 +11,8 @@ import android.content.pm.PackageManager
 import android.graphics.Color
 import android.os.Build
 import android.os.CountDownTimer
+import android.os.Handler
+import android.os.Looper
 import android.util.Log
 import androidx.core.app.ActivityCompat
 import androidx.core.app.NotificationCompat
@@ -383,6 +385,18 @@ object XrayCoreManager {
 
         } catch (e: Exception) {
             Log.e(TAG, "Failed to start Xray process", e)
+            // The process may already be running: pb.start() succeeds before
+            // anything below it can throw. Leaving it alive leaked one live
+            // core per recovery attempt. Clear the field BEFORE destroying so
+            // the monitor thread's `xrayProcess === process` guard fails and
+            // recovery is not re-entered for a core we are killing here.
+            val orphan = xrayProcess
+            xrayProcess = null
+            try {
+                orphan?.destroy()
+            } catch (destroyError: Exception) {
+                Log.w(TAG, "Failed to destroy partially started Xray process", destroyError)
+            }
             deleteEphemeralConfigOnFailure(configFilesDir)
             return false
         }
@@ -429,7 +443,25 @@ object XrayCoreManager {
                AppConfigs.V2RAY_STATE == AppConfigs.V2RAY_STATES.V2RAY_CONNECTING
     }
 
+    // CountDownTimer builds a Handler, so it only constructs on a looper thread.
+    // Core recovery runs on a bare Thread (XrayVPNService.handleXrayCoreExit),
+    // where this threw "Can't create handler inside thread ... that has not
+    // called Looper.prepare()" and took the whole restart down with it.
+    private val mainHandler = Handler(Looper.getMainLooper())
+
+    private fun runOnMain(block: () -> Unit) {
+        if (Looper.myLooper() == Looper.getMainLooper()) block() else mainHandler.post(block)
+    }
+
     private fun startTimer(context: Context) {
+        // Captured now: a stop that lands while the post is queued must not
+        // leave a timer ticking for a generation that is already gone.
+        val token = AppConfigs.V2RAY_CONFIG?.RUNTIME_TOKEN
+        runOnMain { startTimerOnMain(context, token) }
+    }
+
+    private fun startTimerOnMain(context: Context, token: String?) {
+        if (AppConfigs.V2RAY_CONFIG?.RUNTIME_TOKEN != token) return
         countDownTimer?.cancel()
         seconds = 0
         countDownTimer = object : CountDownTimer(Long.MAX_VALUE, 1000) {
@@ -454,10 +486,12 @@ object XrayCoreManager {
     }
 
     private fun stopTimer() {
+        runOnMain {
             countDownTimer?.cancel()
             countDownTimer = null
             seconds = 0
         }
+    }
 
     fun sendStatusBroadcast(context: Context, config: XrayConfig) {
         val intent = Intent(AppConfigs.V2RAY_CONNECTION_INFO).setPackage(context.packageName)