Track registered context menus

So we can refer to them when the host executes a menu item later.

src/wine-host/bridges/vst3-impls/context-menu-proxy.cpp

@@ -21,7 +21,9 @@
 Vst3ContextMenuProxyImpl::Vst3ContextMenuProxyImpl(
     Vst3Bridge& bridge,
     Vst3ContextMenuProxy::ConstructArgs&& args)
-    : Vst3ContextMenuProxy(std::move(args)), bridge(bridge) {}
+    : Vst3ContextMenuProxy(std::move(args)), bridge(bridge) {
+    bridge.register_context_menu(*this);
+}
 
 Vst3ContextMenuProxyImpl::~Vst3ContextMenuProxyImpl() {
     // Also drop the context menu smart pointer on plugin side when this gets
@@ -29,6 +31,7 @@ Vst3ContextMenuProxyImpl::~Vst3ContextMenuProxyImpl() {
     bridge.send_message(
         Vst3ContextMenuProxy::Destruct{.owner_instance_id = owner_instance_id(),
                                        .context_menu_id = context_menu_id()});
+    bridge.unregister_context_menu(owner_instance_id(), context_menu_id());
 }
 
 tresult PLUGIN_API

src/wine-host/bridges/vst3.cpp

@@ -858,6 +858,25 @@ void Vst3Bridge::handle_win32_events() {
     }
 }
 
+void Vst3Bridge::register_context_menu(Vst3ContextMenuProxy& context_menu) {
+    std::lock_guard lock(object_instances[context_menu.owner_instance_id()]
+                             .registered_context_menus_mutex);
+
+    object_instances[context_menu.owner_instance_id()]
+        .registered_context_menus.emplace(
+            context_menu.context_menu_id(),
+            std::ref<Vst3ContextMenuProxy>(context_menu));
+}
+
+void Vst3Bridge::unregister_context_menu(size_t object_instance_id,
+                                         size_t context_menu_id) {
+    std::lock_guard lock(
+        object_instances[object_instance_id].registered_context_menus_mutex);
+
+    object_instances[object_instance_id].registered_context_menus.erase(
+        context_menu_id);
+}
+
 size_t Vst3Bridge::generate_instance_id() {
     return current_instance_id.fetch_add(1);
 }

src/wine-host/bridges/vst3.h

@@ -104,6 +104,20 @@ struct InstanceInterfaces {
      */
     Steinberg::IPtr<Vst3PlugFrameProxy> plug_frame_proxy;
 
+    /**
+     * Currently active context menu proxy instances. A call to
+     * `IComponentHandler3::createContextMenu` by the plugin will create a proxy
+     * object for the actual context menu returned by the host. We'll use this
+     * map to refer to a specific context menu later when the host wants to
+     * execute a specific menu item.
+     *
+     * @relates Vst3Bridge::register_context_menu
+     * @relates Vst3Bridge::unregister_context_menu
+     */
+    std::map<size_t, std::reference_wrapper<Vst3ContextMenuProxy>>
+        registered_context_menus;
+    std::mutex registered_context_menus_mutex;
+
     /**
      * The base object we cast from.
      */
@@ -291,6 +305,21 @@ class Vst3Bridge : public HostBridge {
         return do_call_response.get();
     }
 
+    /**
+     * Register a context with with `context_menu`'s ID and owner in
+     * `object_instances`. This will be called during the constructor of
+     * `Vst3ContextMenuProxyImpl` so we can refer to the exact instance later.
+     */
+    void register_context_menu(Vst3ContextMenuProxy& context_menu);
+
+    /**
+     * Remove a previously registered context menu from `object_instances`. This
+     * is called from the destructor of `Vst3ContextMenuProxyImpl` just before
+     * the object gets freed.
+     */
+    void unregister_context_menu(size_t object_instance_id,
+                                 size_t context_menu_id);
+
    private:
     Logger generic_logger;