Revize 30c849e4

re #9567 Made sure that there is only one running process of the application.

ld_client/LDClient/Program.cs

@@ -5 +5 @@
 using LDClient.utils;
 using LDClient.utils.loggers;
 
+using static System.Diagnostics.Process;
+using static System.Reflection.Assembly;
+
 namespace LDClient;
 
-internal class Program {
+internal static class Program {
 
-    public static ConfigLoader Config { get; set; } = new();
+    public static ConfigLoader Config { get; } = new();
     public static ALogger DefaultLogger { get; } = ALogger.Current;
-
-    public static IApiClient DefaultApiClient { get; set; } = new ApiClient(Config.ApiBaseAddress,
-        Config.ApiPort, Config.ApiUsbEndPoint, Config.RetryPeriod, Config.MaxEntries,
-        Config.MaxRetries, Config.CacheFileName);
-
-
-    private static NetworkDetection _netDetect = new(Config.ApiPort, Config.DetectionPeriod);
-    private static ProcessDetection _procDetect = new(Config.T32ProcessName, Config.DetectionPeriod);
-
-
+    private static IApiClient? DefaultApiClient { get; set; }
+    private static readonly NetworkDetection NetDetect = new(Config.ApiPort, Config.DetectionPeriod);
+    private static readonly ProcessDetection ProcDetect = new(Config.T32ProcessName, Config.DetectionPeriod);
+    
     // Main Method
-    public static async Task Main() {
+    public static int Main() {
+        var exists = GetProcessesByName(Path.GetFileNameWithoutExtension(GetEntryAssembly()?.Location)).Length > 1;
+        if (exists) {
+            DefaultLogger.Error("Another instance of the application is already running");
+            return 1;
+        }
+        
+        DefaultApiClient = new ApiClient(
+            Config.ApiBaseAddress,
+            Config.ApiPort, 
+            Config.ApiUsbEndPoint, 
+            Config.RetryPeriod, Config.MaxEntries,
+            Config.MaxRetries, 
+            Config.CacheFileName
+        );
+        
+        DefaultLogger.Debug("Main -> starting the ApiClient");
         var apiClientThread = new Thread(DefaultApiClient.Run) {
             IsBackground = true
         };
-        DefaultLogger.Debug("Main -> starting the ApiClient");
         apiClientThread.Start();
 
         var admin = IsAdministrator();
         DefaultLogger.Debug($"Is program executed with admin rights? {admin}");
 
-        var networkTread = new Thread(_netDetect.RunPeriodicDetection);
+        var networkTread = new Thread(NetDetect.RunPeriodicDetection);
         networkTread.Start();
+        
         if (admin) {
-            _procDetect.RegisterProcessListeners();
-
+            ProcDetect.RegisterProcessListeners();
         } else {
-            var processThread = new Thread(_procDetect.RunPeriodicDetection);
+            var processThread = new Thread(ProcDetect.RunPeriodicDetection);
             processThread.Start();
             processThread.Join();
         }
@@ -49 +61 @@
         DefaultApiClient.Stop();
         apiClientThread.Join();
         DefaultLogger.Debug("Main -> finished");
+        
+        return 0;
     }
 
-    public static bool IsAdministrator() {
-        if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
-            var identity = WindowsIdentity.GetCurrent();
-            var principal = new WindowsPrincipal(identity);
-            return principal.IsInRole(WindowsBuiltInRole.Administrator);
-
-        } else {
+    private static bool IsAdministrator() {
+        if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
             return false;
         }
+        var identity = WindowsIdentity.GetCurrent();
+        var principal = new WindowsPrincipal(identity);
+        return principal.IsInRole(WindowsBuiltInRole.Administrator);
     }
 }