From b9d5a63c235db5a42e93d0262dd1ef3a5dc5cd6d Mon Sep 17 00:00:00 2001
From: Mygod <contact-github@mygod.be>
Date: Thu, 4 Oct 2018 15:56:24 +0800
Subject: [PATCH] Add synchronization in IpNeighbourMonitor

---
 .../vpnhotspot/net/monitor/IpNeighbourMonitor.kt     | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/mobile/src/main/java/be/mygod/vpnhotspot/net/monitor/IpNeighbourMonitor.kt b/mobile/src/main/java/be/mygod/vpnhotspot/net/monitor/IpNeighbourMonitor.kt
index 55f0577f..427668fb 100644
--- a/mobile/src/main/java/be/mygod/vpnhotspot/net/monitor/IpNeighbourMonitor.kt
+++ b/mobile/src/main/java/be/mygod/vpnhotspot/net/monitor/IpNeighbourMonitor.kt
@@ -10,8 +10,8 @@ class IpNeighbourMonitor private constructor() : IpMonitor() {
         private val callbacks = HashSet<Callback>()
         var instance: IpNeighbourMonitor? = null
 
-        fun registerCallback(callback: Callback) {
-            if (!callbacks.add(callback)) return
+        fun registerCallback(callback: Callback) = synchronized(this) {
+            if (!callbacks.add(callback)) return@synchronized
             var monitor = instance
             if (monitor == null) {
                 monitor = IpNeighbourMonitor()
@@ -21,8 +21,8 @@ class IpNeighbourMonitor private constructor() : IpMonitor() {
                 callback.onIpNeighbourAvailable(synchronized(monitor.neighbours) { monitor.neighbours.values.toList() })
             }
         }
-        fun unregisterCallback(callback: Callback) {
-            if (!callbacks.remove(callback) || callbacks.isNotEmpty()) return
+        fun unregisterCallback(callback: Callback) = synchronized(this) {
+            if (!callbacks.remove(callback) || callbacks.isNotEmpty()) return@synchronized
             instance?.destroy()
             instance = null
         }
@@ -67,7 +67,9 @@ class IpNeighbourMonitor private constructor() : IpMonitor() {
                 updatePosted = false
                 neighbours.values.toList()
             }
-            for (callback in callbacks) callback.onIpNeighbourAvailable(neighbours)
+            synchronized(IpNeighbourMonitor) {
+                for (callback in callbacks) callback.onIpNeighbourAvailable(neighbours)
+            }
         }
         updatePosted = true
     }