Fix AccessViolationException on application shutdown (Ctrl+C)

csharp/Platform.Data.Doublets.Gql.Server/Data.cs

@@ -1,17 +1,32 @@
 using Platform.Data.Doublets.Memory.Split.Generic;
 using Platform.Memory;
+using System;
 
 namespace Platform.Data.Doublets.Gql.Server
 {
     public class Data
     {
         public static string DefaultDatabaseFileName = "db.links";
+        private static SplitMemoryLinks<ulong>? _disposableLinks;
 
         public static ILinks<ulong> CreateLinks()
         {
             // var disposableLinks = new UnitedMemoryLinks<ulong>(new FileMappedResizableDirectMemory(DefaultDatabaseFileName), UnitedMemoryLinks<ulong>.DefaultLinksSizeStep, new LinksConstants<ulong>(enableExternalReferencesSupport: true), IndexTreeType.Default);
-            var disposableLinks = new SplitMemoryLinks<ulong>(new FileMappedResizableDirectMemory(DefaultDatabaseFileName), new FileMappedResizableDirectMemory(DefaultDatabaseFileName + ".index"), SplitMemoryLinks<ulong>.DefaultLinksSizeStep, new LinksConstants<ulong>(true));
-            return new SynchronizedLinks<ulong>(disposableLinks.DecorateWithAutomaticUniquenessAndUsagesResolution());
+            _disposableLinks = new SplitMemoryLinks<ulong>(new FileMappedResizableDirectMemory(DefaultDatabaseFileName), new FileMappedResizableDirectMemory(DefaultDatabaseFileName + ".index"), SplitMemoryLinks<ulong>.DefaultLinksSizeStep, new LinksConstants<ulong>(true));
+            return new SynchronizedLinks<ulong>(_disposableLinks.DecorateWithAutomaticUniquenessAndUsagesResolution());
+        }
+
+        public static void DisposeLinks()
+        {
+            try
+            {
+                _disposableLinks?.Dispose();
+                _disposableLinks = null;
+            }
+            catch (Exception)
+            {
+                // Suppress exceptions during disposal to prevent AccessViolationException
+            }
         }
     }
 }

csharp/Platform.Data.Doublets.Gql.Server/LinksLifetimeService.cs

@@ -0,0 +1,51 @@
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Platform.Data.Doublets.Gql.Server
+{
+    public class LinksLifetimeService : IHostedService
+    {
+        private readonly ILogger<LinksLifetimeService> _logger;
+        private readonly IHostApplicationLifetime _lifetime;
+
+        public LinksLifetimeService(ILogger<LinksLifetimeService> logger, IHostApplicationLifetime lifetime)
+        {
+            _logger = logger;
+            _lifetime = lifetime;
+        }
+
+        public Task StartAsync(CancellationToken cancellationToken)
+        {
+            _lifetime.ApplicationStopping.Register(OnApplicationStopping);
+            _lifetime.ApplicationStopped.Register(OnApplicationStopped);
+            return Task.CompletedTask;
+        }
+
+        public Task StopAsync(CancellationToken cancellationToken)
+        {
+            return Task.CompletedTask;
+        }
+
+        private void OnApplicationStopping()
+        {
+            _logger.LogInformation("Application is stopping, disposing links...");
+            try
+            {
+                Data.DisposeLinks();
+                _logger.LogInformation("Links disposed successfully");
+            }
+            catch (Exception ex)
+            {
+                _logger.LogWarning(ex, "Error occurred while disposing links during application stop");
+            }
+        }
+
+        private void OnApplicationStopped()
+        {
+            _logger.LogInformation("Application stopped");
+        }
+    }
+}

csharp/Platform.Data.Doublets.Gql.Server/Program.cs

@@ -30,6 +30,15 @@ public static int Main(params string[] args)
             }
             finally
             {
+                try
+                {
+                    Log.Information("Disposing links before shutdown");
+                    Data.DisposeLinks();
+                }
+                catch (Exception ex)
+                {
+                    Log.Warning(ex, "Error during links disposal");
+                }
                 Log.CloseAndFlush();
             }
         }

csharp/Platform.Data.Doublets.Gql.Server/Startup.cs

@@ -29,6 +29,7 @@ public Startup(IConfiguration configuration, IWebHostEnvironment environment)
         // This method gets called by the runtime. Use this method to add services to the container.
         public void ConfigureServices(IServiceCollection services) => services.AddSingleton(sp => Data.CreateLinks())
             .AddSingleton<LinksSchema>()
+            .AddHostedService<LinksLifetimeService>()
             .AddGraphQL((options, provider) =>
             {
                 options.EnableMetrics = Environment.IsDevelopment();

csharp/Platform.Data.Doublets.Gql.Server/StartupWithRouting.cs

@@ -39,6 +39,7 @@ public void ConfigureServices(IServiceCollection services) => services.AddRoutin
             })
             .AddSingleton(sp => Data.CreateLinks())
             .AddSingleton<LinksSchema>()
+            .AddHostedService<LinksLifetimeService>()
             .AddGraphQL((options, provider) =>
             {
                 options.EnableMetrics = Environment.IsDevelopment();