Implement IPluginFactory::getClassInfo

src/common/serialization/vst3/plugin-factory.cpp

@@ -26,12 +26,24 @@ YaPluginFactory::YaPluginFactory(
     // TODO: We should only copy the interfaces that we support. This should use
     //       the same list as that used in `createInstance()`.
     known_iids.insert(factory->iid);
+
     if (Steinberg::PFactoryInfo info;
         factory->getFactoryInfo(&info) == Steinberg::kResultOk) {
         factory_info = info;
     }
+
     num_classes = factory->countClasses();
 
+    // TODO: At this point we don't know what this class is and thus we can't
+    //       filter unsupported classes, right?
+    class_infos_1.resize(num_classes);
+    for (int i = 0; i < num_classes; i++) {
+        Steinberg::PClassInfo info;
+        if (factory->getClassInfo(i, &info) == Steinberg::kResultOk) {
+            class_infos_1[i] = info;
+        }
+    }
+
     auto factory2 = Steinberg::FUnknownPtr<Steinberg::IPluginFactory2>(factory);
     if (!factory2) {
         return;
@@ -93,11 +105,18 @@ int32 PLUGIN_API YaPluginFactory::countClasses() {
     return num_classes;
 }
 
-tresult PLUGIN_API
-YaPluginFactory::getClassInfo(Steinberg::int32 /*index*/,
-                              Steinberg::PClassInfo* /*info*/) {
-    // TODO: Implement
-    return 0;
+tresult PLUGIN_API YaPluginFactory::getClassInfo(Steinberg::int32 index,
+                                                 Steinberg::PClassInfo* info) {
+    if (index >= static_cast<int32>(class_infos_1.size())) {
+        return Steinberg::kInvalidArgument;
+    }
+
+    if (class_infos_1[index]) {
+        *info = *class_infos_1[index];
+        return Steinberg::kResultOk;
+    } else {
+        return Steinberg::kResultFalse;
+    }
 }
 
 tresult PLUGIN_API

src/common/serialization/vst3/plugin-factory.h

@@ -86,10 +86,22 @@ class YaPluginFactory : public Steinberg::IPluginFactory3 {
      */
     std::set<Steinberg::FUID> known_iids;
 
-    // For `IPluginFactory::getFactoryInfo`
+    /**
+     * For `IPluginFactory::getFactoryInfo`.
+     */
     std::optional<Steinberg::PFactoryInfo> factory_info;
-    // For `IPluginFactory::countClasses`
+    /**
+     * For `IPluginFactory::countClasses`.
+     */
     int num_classes;
+    /**
+     * For `IPluginFactory::getClassInfo`. We need to store all four class info
+     * versions if the plugin can provide them since we don't know which version
+     * of the interface the host will use. Will be `std::nullopt` if the plugin
+     * doesn't return a class info.
+     */
+    std::vector<std::optional<Steinberg::PClassInfo>> class_infos_1;
+    // TODO: Callback interface for `createInstance()`
 
     template <typename S>
     void serialize(S& s) {
@@ -97,9 +109,12 @@ class YaPluginFactory : public Steinberg::IPluginFactory3 {
               [](S& s, Steinberg::FUID& iid) {
                   s.ext(iid, bitsery::ext::FUID{});
               });
-        s.ext(factory_info, bitsery::ext::StdOptional{},
-              [](S& s, Steinberg::PFactoryInfo& info) { s.object(info); });
+        s.ext(factory_info, bitsery::ext::StdOptional{});
         s.value4b(num_classes);
+        s.container(class_infos_1, 2048,
+                    [](S& s, std::optional<Steinberg::PClassInfo>& info) {
+                        s.ext(info, bitsery::ext::StdOptional{});
+                    });
     }
 };
 
@@ -108,6 +123,14 @@ class YaPluginFactory : public Steinberg::IPluginFactory3 {
 // Serialization functions have to live in the same namespace as the objects
 // they're serializing
 namespace Steinberg {
+template <typename S>
+void serialize(S& s, PClassInfo& class_info) {
+    s.container1b(class_info.cid);
+    s.value4b(class_info.cardinality);
+    s.text1b(class_info.category);
+    s.text1b(class_info.name);
+}
+
 template <typename S>
 void serialize(S& s, PFactoryInfo& factory_info) {
     s.text1b(factory_info.vendor);