Bundle associated messages with their interfaces

Once we start implementing all of the control messages/callbacks things
could quickly get out of hand otherwise.

src/common/logging/vst3.cpp

@@ -24,7 +24,7 @@
 
 Vst3Logger::Vst3Logger(Logger& generic_logger) : logger(generic_logger) {}
 
-void Vst3Logger::log_request(bool is_host_vst, const CreateInstaneIComponent&) {
+void Vst3Logger::log_request(bool is_host_vst, const YaComponent::Create&) {
     if (BOOST_UNLIKELY(logger.verbosity >= Logger::Verbosity::most_events)) {
         std::ostringstream message;
         // TODO: Log the cid in some readable way, if possible

src/common/logging/vst3.h

@@ -45,7 +45,7 @@ class Vst3Logger {
     // flag here indicates whether the request was initiated on the host side
     // (what we'll call a control message).
 
-    void log_request(bool is_host_vst, const CreateInstaneIComponent&);
+    void log_request(bool is_host_vst, const YaComponent::Create&);
     void log_request(bool is_host_vst, const WantsConfiguration&);
     void log_request(bool is_host_vst, const WantsPluginFactory&);
 

src/common/serialization/vst3.h

@@ -38,20 +38,8 @@
 // TODO: If this approach works, maybe we can also refactor the VST2 handling to
 //       do this since it's a bit safer and easier to read
 
-/**
+// All messages for creating objects and calling interfaces on them are defined
- * Request the Wine plugin host to instantiate a new IComponent to pass through
+// as part of the interfaces and implementations in `vst3/`
- * a call to `IPluginFactory::createInstance(cid, IComponent::iid, ...)`.
- */
-struct CreateInstaneIComponent {
-    using Response = YaComponent&;
-
-    Steinberg::TUID cid;
-
-    template <typename S>
-    void serialize(S& s) {
-        s.container1b(cid);
-    }
-};
 
 /**
  * Marker struct to indicate the other side (the plugin) should send a copy of
@@ -80,8 +68,7 @@ struct WantsPluginFactory {
  * encodes the information we request or the operation we want to perform. A
  * request of type `ControlRequest(T)` should send back a `T::Response`.
  */
-using ControlRequest =
+using ControlRequest = std::variant<YaComponent::Create, WantsPluginFactory>;
-    std::variant<CreateInstaneIComponent, WantsPluginFactory>;
 
 template <typename S>
 void serialize(S& s, ControlRequest& payload) {

src/common/serialization/vst3/component.h

@@ -35,6 +35,22 @@ using Steinberg::TBool, Steinberg::int32, Steinberg::tresult;
  */
 class YaComponent : public Steinberg::Vst::IComponent {
    public:
+    /**
+     * Request the Wine plugin host to instantiate a new IComponent to pass
+     * through a call to `IPluginFactory::createInstance(cid, IComponent::iid,
+     * ...)`.
+     */
+    struct Create {
+        using Response = YaComponent&;
+
+        Steinberg::TUID cid;
+
+        template <typename S>
+        void serialize(S& s) {
+            s.container1b(cid);
+        }
+    };
+
     YaComponent();
 
     /**

src/wine-host/bridges/vst3.cpp

@@ -51,8 +51,8 @@ void Vst3Bridge::run() {
     sockets.host_vst_control.receive_messages(
         std::nullopt,
         overload{
-            [&](const CreateInstaneIComponent& args)
+            [&](const YaComponent::Create& args)
-                -> CreateInstaneIComponent::Response {
+                -> YaComponent::Create::Response {
                 Steinberg::IPtr<Steinberg::Vst::IComponent> component =
                     module->getFactory()
                         .createInstance<Steinberg::Vst::IComponent>(args.cid);