[WIP] Use mono_unhandled_exception for NET6

Author: grendello

src/Mono.Android/Android.Runtime/JNIEnv.cs

@@ -242,7 +242,9 @@ static void ManualJavaObjectDispose (Java.Lang.Object obj)
 		}
 
 		static Action<Exception> mono_unhandled_exception = null!;
+#if !NETCOREAPP
 		static Action<AppDomain, UnhandledExceptionEventArgs> AppDomain_DoUnhandledException = null!;
+#endif
 
 		static void Initialize ()
 		{
@@ -253,6 +255,7 @@ static void Initialize ()
 					mono_unhandled_exception = (Action<Exception>) Delegate.CreateDelegate (typeof(Action<Exception>), mono_UnhandledException);
 			}
 
+#if !NETCOREAPP
 			if (AppDomain_DoUnhandledException == null) {
 				var ad_due = typeof (AppDomain)
 					.GetMethod ("DoUnhandledException",
@@ -265,8 +268,14 @@ static void Initialize ()
 						typeof (Action<AppDomain, UnhandledExceptionEventArgs>), ad_due);
 				}
 			}
+#endif
 		}
 
+#if NETCOREAPP
+		[DllImport (AndroidRuntime.InternalDllName, CallingConvention = CallingConvention.Cdecl)]
+		extern static void monodroid_unhandled_exception (Exception javaException);
+#endif
+
 		internal static void PropagateUncaughtException (IntPtr env, IntPtr javaThreadPtr, IntPtr javaExceptionPtr)
 		{
 			if (!PropagateExceptions)
@@ -287,14 +296,18 @@ internal static void PropagateUncaughtException (IntPtr env, IntPtr javaThreadPt
 			try {
 				var jltp = javaException as JavaProxyThrowable;
 				Exception? innerException = jltp?.InnerException;
-				var args  = new UnhandledExceptionEventArgs (innerException ?? javaException, isTerminating: true);
 
 				Logger.Log (LogLevel.Info, "MonoDroid", "UNHANDLED EXCEPTION:");
 				Logger.Log (LogLevel.Info, "MonoDroid", javaException.ToString ());
 
+#if !NETCOREAPP
+				var args  = new UnhandledExceptionEventArgs (innerException ?? javaException, isTerminating: true);
 				// Disabled until Linker error surfaced in https://github.com/xamarin/xamarin-android/pull/4302#issuecomment-596400025 is resolved
 				//AppDomain.CurrentDomain.DoUnhandledException (args);
 				AppDomain_DoUnhandledException?.Invoke (AppDomain.CurrentDomain, args);
+#else
+				monodroid_unhandled_exception (innerException ?? javaException);
+#endif
 			} catch (Exception e) {
 				Logger.Log (LogLevel.Error, "monodroid", "Exception thrown while raising AppDomain.UnhandledException event: " + e.ToString ());
 			}

src/monodroid/jni/monodroid-glue-internal.hh

@@ -174,6 +174,11 @@ namespace xamarin::android::internal
 		}
 
 #if defined (NET6)
+		void unhandled_exception (MonoObject *java_exception)
+		{
+			mono_unhandled_exception (java_exception);
+		}
+
 		void propagate_uncaught_exception (JNIEnv *env, jobject javaThread, jthrowable javaException);
 #else // def NET6
 		void propagate_uncaught_exception (MonoDomain *domain, JNIEnv *env, jobject javaThread, jthrowable javaException);

src/monodroid/jni/pinvoke-override-api.cc

@@ -345,6 +345,12 @@ monodroid_get_dylib (void)
 	return nullptr;
 }
 
+static void
+monodroid_unhandled_exception (MonoObject *java_exception)
+{
+	monodroidRuntime.unhandled_exception (java_exception);
+}
+
 #define PINVOKE_SYMBOL(_sym_) { #_sym_, reinterpret_cast<void*>(&_sym_) }
 
 MonodroidRuntime::pinvoke_api_map MonodroidRuntime::xa_pinvoke_map = {
@@ -583,6 +589,7 @@ MonodroidRuntime::pinvoke_api_map MonodroidRuntime::xa_pinvoke_map = {
 	PINVOKE_SYMBOL (recv_uninterrupted),
 	PINVOKE_SYMBOL (send_uninterrupted),
 	PINVOKE_SYMBOL (set_world_accessable),
+	PINVOKE_SYMBOL (monodroid_unhandled_exception),
 };
 
 MonodroidRuntime::pinvoke_library_map MonodroidRuntime::other_pinvoke_map (MonodroidRuntime::LIBRARY_MAP_INITIAL_BUCKET_COUNT);