From e114bb306ab64502cc6dc3c74ed152d0190a904a Mon Sep 17 00:00:00 2001
From: Mygod <contact-git@mygod.be>
Date: Tue, 23 Jun 2020 07:53:42 +0800
Subject: [PATCH] Fix race in ofInterface

---
 mobile/src/main/java/be/mygod/vpnhotspot/net/TetherType.kt  | 5 +++--
 .../main/java/be/mygod/vpnhotspot/net/TetheringManager.kt   | 6 +++---
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/mobile/src/main/java/be/mygod/vpnhotspot/net/TetherType.kt b/mobile/src/main/java/be/mygod/vpnhotspot/net/TetherType.kt
index 796b8e6d..05b6c1c5 100644
--- a/mobile/src/main/java/be/mygod/vpnhotspot/net/TetherType.kt
+++ b/mobile/src/main/java/be/mygod/vpnhotspot/net/TetherType.kt
@@ -90,13 +90,14 @@ enum class TetherType(@DrawableRes val icon: Int) {
          *
          * Based on: https://android.googlesource.com/platform/frameworks/base/+/5d36f01/packages/Tethering/src/com/android/networkstack/tethering/Tethering.java#479
          */
-        tailrec fun ofInterface(iface: String?, p2pDev: String? = null): TetherType = when {
+        fun ofInterface(iface: String?, p2pDev: String? = null) = synchronized(this) { ofInterfaceImpl(iface, p2pDev) }
+        private tailrec fun ofInterfaceImpl(iface: String?, p2pDev: String?): TetherType = when {
             iface == null -> NONE
             iface == p2pDev -> WIFI_P2P
             requiresUpdate -> {
                 Timber.d("requiresUpdate")
                 if (Build.VERSION.SDK_INT >= 30) updateRegexs() else error("unexpected requiresUpdate")
-                ofInterface(iface, p2pDev)
+                ofInterfaceImpl(iface, p2pDev)
             }
             wifiRegexs.any { it.matcher(iface).matches() } -> WIFI
             wifiP2pRegexs.any { it.matcher(iface).matches() } -> WIFI_P2P
diff --git a/mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt b/mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt
index 197abcbb..299ad7a5 100644
--- a/mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt
+++ b/mobile/src/main/java/be/mygod/vpnhotspot/net/TetheringManager.kt
@@ -464,8 +464,8 @@ object TetheringManager {
          * Only called if having permission one of NETWORK_SETTINGS, MAINLINE_NETWORK_STACK, NETWORK_STACK.
          * @param clients The new set of tethered clients; the collection is not ordered.
          */
-        fun onClientsChanged(clients: Iterable<*>) {
-            Timber.i("onClientsChanged: ${clients.joinToString()}")
+        fun onClientsChanged(clients: Collection<*>) {
+            if (clients.isNotEmpty()) Timber.i("onClientsChanged: ${clients.joinToString()}")
         }
 
         /**
@@ -543,7 +543,7 @@ object TetheringManager {
                             }
                             "onClientsChanged" -> {
                                 if (noArgs != 1) Timber.w("Unexpected args for $name: $args")
-                                callback?.onClientsChanged(args!![0] as Iterable<*>)
+                                callback?.onClientsChanged(args!![0] as Collection<*>)
                             }
                             "onOffloadStatusChanged" -> {
                                 if (noArgs != 1) Timber.w("Unexpected args for $name: $args")