Stop the LSPosed hooks' debug flag from depending on inotify

changelog.d/fixed-turning-debug-logging-off-now-takes-fb2e.md

@@ -0,0 +1,9 @@
+_2026-08-26_
+
+## English
+
+Turning Debug logging off now takes effect in the LSPosed hooks without a reboot. The flag was refreshed only by a filesystem watcher, and when that watcher stopped delivering events the hooks kept writing to logcat for as long as the device stayed up.
+
+## Русский
+
+Выключение отладочного лога теперь доходит до LSPosed-хуков без перезагрузки. Раньше флаг обновлялся только по событию файловой системы, и если это событие терялось, хуки продолжали писать в logcat до перезагрузки устройства.

lsposed/app/src/main/kotlin/dev/okhsunrog/vpnhide/hook/HookLog.kt

@@ -11,9 +11,10 @@ import dev.okhsunrog.vpnhide.VpnHideLog
  * system_server logcat facade for LSPosed hooks, which can't reach the app's
  * canonical-snapshot cache. Same gate-and-level policy as [VpnHideLog] (see
  * [GatedLogger]) — info is per-request/hot-path and gated, error always prints
- * so "hooks didn't attach" reports stay diagnosable — but the flag is read
- * straight from the canonical JSON on [install] and refreshed by an inotify
- * watcher, so a toggle flip lands without restarting system_server.
+ * so "hooks didn't attach" reports stay diagnosable — but the flag is owned by
+ * [SystemServerConfigCache], which re-reads the canonical JSON on the same 1s
+ * stat poll that keeps the hooks' targets current. A toggle flip therefore lands
+ * without restarting system_server, and without trusting inotify to deliver it.
  *
  * Every line also goes to `XposedBridge.log`, keeping Settings → Debugging →
  * Debug logging visible through framework UIs that surface the Xposed log
@@ -23,23 +24,29 @@ internal object HookLog : GatedLogger() {
     @Volatile private var watcher: FileObserver? = null
 
     fun install() {
-        reload()
+        // Priming read: SystemServerConfigCache sets [enabled] whenever it
+        // installs a fresh config, so this both loads the config and seeds the
+        // flag. It is also the only step required for the flag to stay correct
+        // — the watcher below is latency, not correctness.
+        SystemServerConfigCache.load()
         if (watcher != null) return
-        // MODIFY covers manual in-place edits; MOVED_TO/CLOSE_WRITE from
-        // watchSystemDataDir cover the app's atomic JSON replacement.
+        // Makes a toggle flip land immediately instead of within the cache's 1s
+        // stat interval. MODIFY covers manual in-place edits; MOVED_TO/CLOSE_WRITE
+        // from watchSystemDataDir cover the app's atomic JSON replacement.
+        //
+        // Do NOT make anything depend on this firing: on at least one device it
+        // stopped delivering events entirely (see the note in
+        // SystemServerConfigCache.load), which is exactly how the debug flag once
+        // got stuck on for days.
         watcher =
             watchSystemDataDir(extraEvents = FileObserver.MODIFY) { path ->
                 if (path == "vpnhide_config.json") {
                     SystemServerConfigCache.invalidate()
-                    reload()
+                    SystemServerConfigCache.load()
                 }
             }
     }
 
-    private fun reload() {
-        enabled = SystemServerConfigCache.load().debug
-    }
-
     override fun emit(
         priority: Int,
         tag: String,

lsposed/app/src/main/kotlin/dev/okhsunrog/vpnhide/hook/SystemServerConfigCache.kt

@@ -82,6 +82,16 @@ internal object SystemServerConfigCache {
 
             val result = readConfig()
             val loadedFingerprint = fingerprint()
+            // The debug-logging flag rides this same 1s stat poll as everything
+            // else the hooks read. It used to be refreshed only by HookLog's
+            // FileObserver, and on a Pixel 8 Pro that observer silently stopped
+            // delivering: an atomic rename over the config produced no callback
+            // at all, so the flag stayed frozen at its boot value for five days
+            // while this cache — reading the very same file — was current the
+            // whole time. Turning Debug logging off in the app simply never
+            // reached system_server, and the hooks kept naming target UIDs in
+            // logcat. Correctness must not depend on inotify.
+            HookLog.enabled = result.debug
             HookLog.i(
                 "VpnHide: system_server config loaded " +
                     "java=${result.javaTargetAppIds.size} observer=${result.observerAppIds.size} " +