Cleanup crashes fix

src/SampSharp.OpenMp.Entities/Hosting/EcsHost.cs

@@ -27,12 +27,23 @@ protected override void Cleanup()
     {
         OnGameModeExit();
 
-        if (_serviceProvider is IDisposable disposable)
+        if (_serviceProvider is not IDisposable disposable)
         {
-            //  TODO: This cleanup is called so late - we can't unsubscribe event handlers anymore, but the disposables in registered systems will try to unsubscribe them. This may cause a System.ExecutionEngineException on shutdown.
-            disposable.Dispose();
-            _serviceProvider = null;
+            return;
         }
+
+        // Cleanup runs after open.mp has already started tearing down other components
+        // pointers in IComponentList / ICore are unsafe to deref by now, so we flag the
+        // environment as shutting down and let SafeEventHandlerRegistration etc. skip
+        // their native unsubscribe calls. Without this, disposing systems crashes with
+        // an AV in IComponentList::QueryComponent.
+        if (_serviceProvider.GetService<SampSharpEnvironment>() is { } environment)
+        {
+            environment.IsShuttingDown = true;
+        }
+
+        disposable.Dispose();
+        _serviceProvider = null;
     }
 
     private void UnhandledExceptionHandler(string context, Exception exception)

src/SampSharp.OpenMp.Entities/Hosting/SampSharpEnvironment.cs

@@ -13,4 +13,14 @@ namespace SampSharp.Entities;
 /// <param name="EntryAssembly">The assembly which was configured to launch in open.mp. Used to discover game mode classes and other application types.</param>
 /// <param name="Core">The <see cref="ICore" /> interface for the open.mp server. Provides access to core server functionality and extensions.</param>
 /// <param name="Components">The <see cref="IComponentList" /> of open.mp. Manages all game components (players, vehicles, objects, etc.) accessible on the server.</param>
-public record SampSharpEnvironment(Assembly EntryAssembly, ICore Core, IComponentList Components);
+public record SampSharpEnvironment(Assembly EntryAssembly, ICore Core, IComponentList Components)
+{
+    /// <summary>
+    /// Indicates that the host is in the process of shutting down. Set during <c>EcsHost.Cleanup</c>
+    /// before the DI scope is disposed. While true, code paths that rely on native open.mp objects
+    /// (e.g. component lookups via P/Invoke) must skip those calls — by this point open.mp may have
+    /// already torn down components, and re-entering native code can crash with an access violation
+    /// (we have observed this in <c>SafeEventHandlerRegistration.Dispose</c>).
+    /// </summary>
+    public bool IsShuttingDown { get; internal set; }
+}

src/SampSharp.OpenMp.Entities/Systems/SafeEventHandlerRegistration.cs

@@ -17,6 +17,16 @@ public void Dispose()
 
         _disposed = true;
 
+        // During host shutdown the native IComponentList/ICore pointers may already be
+        // invalidated by open.mp. Calling QueryComponent here would crash with an AV in
+        // the P/Invoke trampoline before HasValue could even return false. Just free the
+        // marshalled handler and skip the unsubscribe — the native side is going away.
+        if (environment.IsShuttingDown)
+        {
+            TEventHandler.Marshaller.Marshal(handler).Free();
+            return;
+        }
+
         var component = environment.Components.QueryComponent<TComponent>();
 
         if (!component.HasValue)
@@ -51,6 +61,13 @@ public void Dispose()
 
         _disposed = true;
 
+        // See note in the component-typed overload above — same reasoning for ICore.
+        if (environment.IsShuttingDown)
+        {
+            TEventHandler.Marshaller.Marshal(handler).Free();
+            return;
+        }
+
         if (!environment.Core.HasValue)
         {
             TEventHandler.Marshaller.Marshal(handler).Free();

src/sampsharp-component/managed-host.cpp

@@ -214,6 +214,10 @@ const char * ManagedHost::get_error(int code) const
         case 0x800080a6: return "Hosting API does not support the requested scenario";
         case 0x800080a7: return "Support for a requested feature is disabled";
         case ERROR_MISSING_EXPORT: return "Missing export fuction in host library";
-        default: return "Unkown error";
+        default: {
+            static thread_local char buf[64];
+            snprintf(buf, sizeof(buf), "Unknown HRESULT 0x%08X", static_cast<unsigned int>(code));
+            return buf;
+        }
     }
 }