Microsoft.Common.Core.Logging.Implementation.LoggingServices.GetOrCreateLog C# (CSharp) Method

        public IActionLog GetOrCreateLog(string appName) {
            if (_instance == null) {
                var instance = new Logger(_appConstants.ApplicationName, Permissions, writer: null);
                Interlocked.CompareExchange(ref _instance, instance, null);
            }
            return _instance;
        }

        public CoreServices(IApplicationConstants appConstants
            , ITelemetryService telemetry
            , ITaskService tasks
            , IMainThread mainThread
            , ISecurityService security) {
            Telemetry = telemetry;
            Registry = new RegistryImpl();
            Security = security;
            LoggingServices = new LoggingServices(new LoggingPermissions(appConstants, telemetry, Registry), appConstants);
            Tasks = tasks;

            ProcessServices = new ProcessServices();
            FileSystem = new FileSystem();
            MainThread = mainThread;

            Log = LoggingServices.GetOrCreateLog(appConstants.ApplicationName);
        }