Use lock to prevent clearing early

library/build.gradle

@@ -7,7 +7,7 @@ group = 'com.frostnerd.utilskt'
 ext {
     libraryGroupId = group
     libraryArtifactId = rootProject.name
-    libraryVersion = '3.1.11'
+    libraryVersion = '3.1.12'
 }
 
 android {

library/src/main/java/com/frostnerd/vpntunnelproxy/VPNTunnelProxy.kt

@@ -14,7 +14,10 @@ import java.io.*
 import java.net.DatagramSocket
 import java.net.Socket
 import java.util.concurrent.locks.ReentrantLock
+import java.util.concurrent.locks.ReentrantReadWriteLock
+import kotlin.concurrent.read
 import kotlin.concurrent.withLock
+import kotlin.concurrent.write
 
 /*
  * Copyright (C) 2019 Daniel Wolf (Ch4t4r)
@@ -66,6 +69,7 @@ open class VPNTunnelProxy(val packetProxy: PacketProxy,
     var forwardingMode:ForwardingMode = ForwardingMode.MIXED
     private var proxyThreadActive:Boolean = false
     private var cleanupFinalized:Boolean = false
+    private val clearLock = ReentrantReadWriteLock()
 
     constructor(packetProxy: PacketProxy,
                 trafficStats: TrafficStats = TrafficStats(0, 0),
@@ -141,6 +145,8 @@ open class VPNTunnelProxy(val packetProxy: PacketProxy,
         proxyThread = Thread {
             proxyThreadActive = true
             logger?.info("Proxy started on thread " + Thread.currentThread().name)
+            val lock = clearLock.readLock()
+            lock.lock()
             try {
                 try {
                     while(shouldRun) {
@@ -193,11 +199,14 @@ open class VPNTunnelProxy(val packetProxy: PacketProxy,
             } finally {
                 logger?.info("Proxy thread ended.")
                 proxyThreadActive = false
+                lock.unlock()
                 finalizeCleanup()
             }
         }
         if(forwardingMode != ForwardingMode.ONLY_POLLABLE) nonPollableProxyThread = Thread {
             logger?.info("Non-pollable proxy started on thread " + Thread.currentThread().name)
+            val lock = clearLock.readLock()
+            lock.lock()
             try {
                 while (shouldRun) {
                     forwardedPacketStore?.processNewAnswers(false)
@@ -217,6 +226,8 @@ open class VPNTunnelProxy(val packetProxy: PacketProxy,
             } catch (ex:java.lang.Exception) {
                 if (exceptionCallbacks.isEmpty()) throw ex
                 else errorOccurred(ex)
+            } finally {
+                lock.unlock()
             }
             logger?.info("Non-pollable proxy ended. Should run: $shouldRun")
         }
@@ -274,17 +285,19 @@ open class VPNTunnelProxy(val packetProxy: PacketProxy,
     }
 
     private fun finalizeCleanup() {
-        proxyThread = null
-        nonPollableProxyThread = null
-        for (fileDescriptor in pipesToClose) {
-            fileDescriptor.tryClosing()
+        clearLock.write {
+            proxyThread = null
+            nonPollableProxyThread = null
+            for (fileDescriptor in pipesToClose) {
+                fileDescriptor.tryClosing()
+            }
+            pipesToClose.clear()
+            forwardedPacketStore?.clear(proxyStopped)
+            tunnelHandle?.clear(false)
+            cleanupFinalized = true
+            cleanupCallbacks.forEach { it() }
+            cleanupCallbacks.clear()
         }
-        pipesToClose.clear()
-        forwardedPacketStore?.clear(proxyStopped)
-        tunnelHandle?.clear(false)
-        cleanupFinalized = true
-        cleanupCallbacks?.forEach { it() }
-        cleanupCallbacks.clear()
     }
 
     @Throws(ErrnoException::class)