Cleanup callback handling

Author: twistedfall

binding-generator/src/writer/rust_native/func.rs

@@ -244,7 +244,8 @@ impl RustNativeGeneratedElement for Func<'_, '_> {
 			if arg.is_user_data() {
 				pre_post_arg_handle(
 					format!(
-						"userdata_arg!({name} in callbacks => {callback_name})",
+						"userdata_arg!({decl} => {callback_name})",
+						decl = arg_type_ref.render_lane().to_dyn().rust_extern_arg_func_decl(name),
 						callback_name = callback_arg_name.expect("Can't get name of the callback arg")
 					),
 					&mut pre_call_args,

binding-generator/src/writer/rust_native/type_ref/render_lane/function.rs

@@ -53,10 +53,9 @@ impl RenderLaneTrait for FunctionRenderLane<'_, '_> {
 				.join(", ");
 			let ret = self.func.return_type();
 			format!(
-				"callback_arg!({name}_trampoline({tramp_args}) -> {tramp_ret} => {userdata_name} in callbacks => {name}({fw_args}) -> {fw_ret})",
+				"callback_arg!({name}_trampoline({tramp_args}) -> {ret} => {userdata_name} in {name}({fw_args}) -> {ret})",
 				tramp_args = tramp_args.iter().map(|(_, decl)| decl).join(", "),
-				tramp_ret = ret.rust_extern(ExternDir::FromCpp),
-				fw_ret = ret.rust_extern(ExternDir::FromCpp),
+				ret = ret.rust_extern(ExternDir::FromCpp),
 			)
 		} else {
 			"".to_string()

src/templ.rs

@@ -31,26 +31,25 @@ macro_rules! string_arg_output_receive {
 }
 
 macro_rules! callback_arg {
-	($tr_name: ident($($tr_arg_name: ident: $tr_arg_type: ty),*) -> $tr_ret: ty => $tr_userdata_name: ident in $callbacks_name: ident => $callback_name: ident($($fw_arg_name: ident: $fw_arg_type: ty),*) -> $fw_ret: ty) => {
+	($tr_name: ident($($tr_arg_name: ident: $tr_arg_type: ty),*) -> $tr_ret: ty => $tr_userdata_name: ident in $callback_name: ident($($fw_arg_name: ident: $fw_arg_type: ty),*) -> $fw_ret: ty) => {
 		unsafe extern "C" fn trampoline($($tr_arg_name: $tr_arg_type),*) -> $tr_ret {
-			let mut callback: Box<Box<dyn FnMut($($fw_arg_type),*) -> $fw_ret + Send + Sync>> = Box::from_raw($tr_userdata_name.cast());
-			let out = callback($($fw_arg_name),*);
-			Box::into_raw(callback);
+			let callback: *mut Box<dyn FnMut($($fw_arg_type),*) -> $fw_ret> = $tr_userdata_name.cast();
+			let out = (*callback)($($fw_arg_name),*);
 			out
 		}
 
 		let $tr_name = if $callback_name.is_some() {
-			Some(trampoline as unsafe extern "C" fn($($tr_arg_name: $tr_arg_type),*) -> $tr_ret)
+			Some(trampoline as unsafe extern "C" fn($($tr_arg_type),*) -> $tr_ret)
 		} else {
 			None
 		};
 	}
 }
 
 macro_rules! userdata_arg {
-	($userdata_name: ident in $callbacks_name: ident => $callback_name: ident) => {
-		let $userdata_name = if let Some(callback) = $callback_name {
-			Box::into_raw(Box::new(callback)).cast::<::std::ffi::c_void>()
+	($userdata_name: ident: $userdata_type: ty => $callback_name: ident) => {
+		let $userdata_name: $userdata_type = if let Some(callback) = $callback_name {
+			Box::into_raw(Box::new(callback)).cast()
 		} else {
 			::std::ptr::null_mut() // fixme, remove previous callback
 		};