stop bgtask when app starts up

Author: Trolldemorted

Signal-Windows.Lib/LibUtils.cs

@@ -61,7 +61,8 @@ await dispatcher.RunAsync(priority, () =>
     public class LibUtils
     {
         private static readonly ILogger Logger = LibsignalLogging.CreateLogger<LibUtils>();
-        public const string GlobalSemaphoreName = "SignalWindowsPrivateMessenger_Mutex";
+        public const string GlobalMutexName = "SignalWindowsPrivateMessenger_Mutex";
+        public const string GlobalEventWaitHandleName = "SignalWindowsPrivateMessenger_EventWaitHandle";
         public static string URL = "https://textsecure-service.whispersystems.org";
         public static SignalServiceUrl[] ServiceUrls = new SignalServiceUrl[] { new SignalServiceUrl(URL, null) };
         public static bool MainPageActive = false;
@@ -74,7 +75,7 @@ public class LibUtils
         internal static void Lock()
         {
             Logger.LogTrace("System lock locking, sync context = {0}", SynchronizationContext.Current);
-            GlobalLock = new Mutex(false, GlobalSemaphoreName, out bool createdNew);
+            GlobalLock = new Mutex(false, GlobalMutexName, out bool createdNew);
             GlobalLockContext = SynchronizationContext.Current;
             try
             {
@@ -89,7 +90,7 @@ internal static void Lock()
 
         public static bool Lock(int timeout)
         {
-            GlobalLock = new Mutex(false, GlobalSemaphoreName, out bool createdNew);
+            GlobalLock = new Mutex(false, GlobalMutexName, out bool createdNew);
             GlobalLockContext = SynchronizationContext.Current;
             Logger.LogTrace("System lock locking with timeout, sync context = {0}", SynchronizationContext.Current);
             bool success = false;
@@ -129,5 +130,23 @@ public static void Unlock()
             }
             Logger.LogTrace("System lock released");
         }
+
+        public static EventWaitHandle OpenResetEventSet()
+        {
+            Logger.LogTrace("OpenResetEventSet()");
+            var handle = new EventWaitHandle(true, EventResetMode.ManualReset, GlobalEventWaitHandleName, out bool createdNew);
+            if(!createdNew)
+            {
+                Logger.LogTrace("OpenResetEventSet() setting old event");
+                handle.Set();
+            }
+            return handle;
+        }
+
+        public static EventWaitHandle OpenResetEventUnset()
+        {
+            Logger.LogTrace("OpenResetEventUnset()");
+            return new EventWaitHandle(false, EventResetMode.ManualReset, GlobalEventWaitHandleName, out bool createdNew);
+        }
     }
 }

Signal-Windows.Lib/SignalLibHandle.cs

@@ -44,6 +44,7 @@ public class SignalLibHandle
         private SignalServiceMessageSender MessageSender;
         private SignalServiceMessageReceiver MessageReceiver;
         public BlockingCollection<SignalMessage> OutgoingQueue = new BlockingCollection<SignalMessage>(new ConcurrentQueue<SignalMessage>());
+        private EventWaitHandle GlobalResetEvent;
 
         public event EventHandler<SignalMessageEventArgs> SignalMessageEvent;
 
@@ -99,7 +100,9 @@ public async Task Acquire(CoreDispatcher d, ISignalFrontend w) //TODO wrap tryca
             Logger.LogTrace("Acquire() locking");
             CancelSource = new CancellationTokenSource();
             SemaphoreSlim.Wait(CancelSource.Token);
+            GlobalResetEvent = LibUtils.OpenResetEventSet();
             LibUtils.Lock();
+            GlobalResetEvent.Reset();
             var getConversationsTask = Task.Run(() =>
             {
                 return GetConversations(); // we want to display the conversations asap!
@@ -146,7 +149,9 @@ public async Task Reacquire()
             Logger.LogTrace("Reacquire() locking");
             CancelSource = new CancellationTokenSource();
             SemaphoreSlim.Wait(CancelSource.Token);
+            GlobalResetEvent = LibUtils.OpenResetEventSet();
             LibUtils.Lock();
+            GlobalResetEvent.Reset();
             LibsignalDBContext.ClearSessionCache();
             Instance = this;
             await Task.Run(() =>

Signal-Windows.RC/SignalBackgroundTask.cs

@@ -25,6 +25,7 @@ public sealed class SignalBackgroundTask : IBackgroundTask
         private SignalLibHandle Handle;
         private ToastNotifier ToastNotifier;
         private AutoResetEvent ResetEvent = new AutoResetEvent(false);
+        private EventWaitHandle GlobalResetEvent;
 
         public void Run(IBackgroundTaskInstance taskInstance)
         {
@@ -42,6 +43,13 @@ public void Run(IBackgroundTaskInstance taskInstance)
                 Deferral.Complete();
                 return;
             }
+            GlobalResetEvent = LibUtils.OpenResetEventUnset();
+            Task.Run(() =>
+            {
+                GlobalResetEvent.WaitOne();
+                Logger.LogInformation("Background task received app startup signal");
+                ResetEvent.Set();
+            });
             try
             {
                 Handle = new SignalLibHandle(true);

Signal-Windows/App.xaml.cs

@@ -161,7 +161,7 @@ protected override async void OnLaunched(LaunchActivatedEventArgs e)
             }
 
 
-            Logger.LogInformation("Launching ({0}) ### 1", e.PreviousExecutionState);
+            Logger.LogInformation("Launching (PreviousExecutionState={0})", e.PreviousExecutionState);
             Logger.LogDebug(LocalCacheFolder.Path);
 
             bool createdMainWindow = await CreateMainWindow(null);