Fix reopening closed editor windows

README.md

@@ -7,8 +7,7 @@ Yet Another way to use Windows VST2 plugins in Linux VST hosts.
 There are a few things that should be done before releasing this, including:
 
 - Fix implementation bugs:
-  - Fix hiding and showing of editor windows, closing a window with alt+f4
-    freezes the editor,
+  - Closing editor windows is slow, this can be improved,
   - Polish GUIs even further. There are some todos left in
     `src/wine-host/editor.{h,cpp}`.
   - There are likely some minor issues left.

src/wine-host/editor.cpp

@@ -30,18 +30,25 @@ xcb_window_t get_x11_handle(HWND win32_handle);
 
 ATOM register_window_class(std::string window_class_name);
 
+WindowClass::WindowClass(std::string name)
+    : atom(register_window_class(name)) {}
+
+WindowClass::~WindowClass() {
+    UnregisterClass(reinterpret_cast<LPCSTR>(atom), GetModuleHandle(nullptr));
+}
+
 Editor::Editor(const std::string& window_class_name,
                AEffect* effect,
                std::mutex& effect_mutex,
                const size_t parent_window_handle)
-    : window_class(register_window_class(window_class_name)),
+    : window_class(window_class_name),
       // Create a window without any decoratiosn for easy embedding. The
       // combination of `WS_EX_TOOLWINDOW` and `WS_POPUP` causes the window to
       // be drawn without any decorations (making resizes behave as you'd
       // expect) and also causes mouse coordinates to be relative to the window
       // itself.
       win32_handle(CreateWindowEx(WS_EX_TOOLWINDOW | WS_EX_ACCEPTFILES,
-                                  reinterpret_cast<LPCSTR>(window_class),
+                                  reinterpret_cast<LPCSTR>(window_class.atom),
                                   "yabridge plugin",
                                   WS_POPUP,
                                   CW_USEDEFAULT,

src/wine-host/editor.h

@@ -17,6 +17,21 @@
 #include <optional>
 #include <string>
 
+/**
+ * A basic RAII wrapper around the Win32 window class system, for use in the
+ * Editor class below.
+ */
+class WindowClass {
+   public:
+    WindowClass(std::string name);
+    ~WindowClass();
+
+    /**
+     * The Win32 window class registered for the windows window.
+     */
+    const ATOM atom;
+};
+
 /**
  * A wrapper around the win32 windowing API to create and destroy editor
  * windows. We can embed this window into the window provided by the host, and a
@@ -74,7 +89,7 @@ class Editor {
     /**
      * The Win32 window class registered for the windows window.
      */
-    ATOM window_class;
+    WindowClass window_class;
 
    public:
     /**