Move EventResultPayload to Vst2EventResult::Payload

src/common/communication/vst2.h

@@ -230,7 +230,7 @@ class Vst2EventHandler : public AdHocSocketHandler<Thread> {
      * an `Vst2Event`. This is almost always uses `passthrough_event()`, which
      * converts a `Vst2Event::Payload` into the format used by VST2, calls
      * either `dispatch()` or `audioMaster()` depending on the context, and then
-     * serializes the result back into an `EventResultPayload`.
+     * serializes the result back into an `Vst2EventResult::Payload`.
      *
      * @param logging A pair containing a logger instance and whether or not
      *   this is for sending `dispatch()` events or host callbacks. Optional
@@ -478,8 +478,8 @@ Vst2EventResult passthrough_event(AEffect* plugin,
 
     // For some payload types we need to write back a value to the data pointer
     auto write_payload_fn = overload{
-        [&](auto) -> EventResultPayload { return nullptr; },
-        [&](const AEffect& updated_plugin) -> EventResultPayload {
+        [&](auto) -> Vst2EventResult::Payload { return nullptr; },
+        [&](const AEffect& updated_plugin) -> Vst2EventResult::Payload {
             // This is a bit of a special case! Instead of writing some return
             // value, we will update values on the native VST plugin's `AEffect`
             // object. This is triggered by the `audioMasterIOChanged` callback
@@ -489,9 +489,11 @@ Vst2EventResult passthrough_event(AEffect* plugin,
             return nullptr;
         },
         [&](DynamicSpeakerArrangement& speaker_arrangement)
-            -> EventResultPayload { return speaker_arrangement; },
-        [&](WantsAEffectUpdate&) -> EventResultPayload { return *plugin; },
-        [&](WantsChunkBuffer&) -> EventResultPayload {
+            -> Vst2EventResult::Payload { return speaker_arrangement; },
+        [&](WantsAEffectUpdate&) -> Vst2EventResult::Payload {
+            return *plugin;
+        },
+        [&](WantsChunkBuffer&) -> Vst2EventResult::Payload {
             // In this case the plugin will have written its data stored in an
             // array to which a pointer is stored in `data`, with the return
             // value from the event determines how much data the plugin has
@@ -500,7 +502,7 @@ Vst2EventResult passthrough_event(AEffect* plugin,
             return ChunkData{
                 std::vector<uint8_t>(chunk_data, chunk_data + return_value)};
         },
-        [&](WantsVstRect&) -> EventResultPayload {
+        [&](WantsVstRect&) -> Vst2EventResult::Payload {
             // The plugin should have written a pointer to a VstRect struct into
             // the data pointer. I haven't seen this fail yet, but since some
             // hosts will call `effEditGetRect()` before `effEditOpen()` I can
@@ -512,7 +514,7 @@ Vst2EventResult passthrough_event(AEffect* plugin,
 
             return *editor_rect;
         },
-        [&](WantsVstTimeInfo&) -> EventResultPayload {
+        [&](WantsVstTimeInfo&) -> Vst2EventResult::Payload {
             // Not sure why the VST API has twenty different ways of
             // returning structs, but in this case the value returned from
             // the callback function is actually a pointer to a
@@ -526,14 +528,16 @@ Vst2EventResult passthrough_event(AEffect* plugin,
                 return *time_info;
             }
         },
-        [&](WantsString&) -> EventResultPayload {
+        [&](WantsString&) -> Vst2EventResult::Payload {
             return std::string(static_cast<char*>(data));
         },
-        [&](VstIOProperties& props) -> EventResultPayload { return props; },
-        [&](VstMidiKeyName& key_name) -> EventResultPayload {
+        [&](VstIOProperties& props) -> Vst2EventResult::Payload {
+            return props;
+        },
+        [&](VstMidiKeyName& key_name) -> Vst2EventResult::Payload {
             return key_name;
         },
-        [&](VstParameterProperties& props) -> EventResultPayload {
+        [&](VstParameterProperties& props) -> Vst2EventResult::Payload {
             return props;
         }};
 
@@ -541,9 +545,9 @@ Vst2EventResult passthrough_event(AEffect* plugin,
     // And as mentioned above, `effGetSpeakerArrangement()` wants the plugin's
     // speaker arrangement to be the data pointer, so we need to do this same
     // serialization step just for that function.
-    const EventResultPayload response_data =
+    const Vst2EventResult::Payload response_data =
         std::visit(write_payload_fn, event.payload);
-    std::optional<EventResultPayload> value_response_data = std::nullopt;
+    std::optional<Vst2EventResult::Payload> value_response_data = std::nullopt;
     if (event.value_payload) {
         value_response_data =
             std::visit(write_payload_fn, *event.value_payload);

src/common/logging/vst2.cpp

@@ -448,8 +448,8 @@ void Vst2Logger::log_event_response(
     bool is_dispatch,
     int opcode,
     intptr_t return_value,
-    const EventResultPayload& payload,
-    const std::optional<EventResultPayload>& value_payload,
+    const Vst2EventResult::Payload& payload,
+    const std::optional<Vst2EventResult::Payload>& value_payload,
     bool from_cache) {
     if (BOOST_UNLIKELY(logger.verbosity >= Logger::Verbosity::most_events)) {
         if (should_filter_event(is_dispatch, opcode)) {

src/common/logging/vst2.h

@@ -73,8 +73,8 @@ class Vst2Logger {
         bool is_dispatch,
         int opcode,
         intptr_t return_value,
-        const EventResultPayload& payload,
-        const std::optional<EventResultPayload>& value_payload,
+        const Vst2EventResult::Payload& payload,
+        const std::optional<Vst2EventResult::Payload>& value_payload,
         bool from_cache = false);
 
     /**

src/common/serialization/vst2.h

@@ -427,33 +427,64 @@ void serialize(S& s, Vst2Event::Payload& payload) {
 }
 
 /**
- * The response for an event. This is usually either:
- *
- * - Nothing, on which case only the return value from the callback function
- *   gets passed along.
- * - A (short) string.
- * - Some binary blob stored as a byte vector. During `effGetChunk` this will
- *   contain some chunk data that should be written to
- *   `Vst2PluginBridge::chunk_data`.
- * - A specific struct in response to an event such as `audioMasterGetTime` or
- *   `audioMasterIOChanged`.
- * - An X11 window pointer for the editor window.
- *
- * @relates passthrough_event
+ * AN instance of this should be sent back as a response to an incoming event.
  */
-using EventResultPayload = std::variant<std::nullptr_t,
-                                        std::string,
-                                        AEffect,
-                                        ChunkData,
-                                        DynamicSpeakerArrangement,
-                                        VstIOProperties,
-                                        VstMidiKeyName,
-                                        VstParameterProperties,
-                                        VstRect,
-                                        VstTimeInfo>;
+struct Vst2EventResult {
+    /**
+     * The response for an event. This is usually either:
+     *
+     * - Nothing, on which case only the return value from the callback function
+     *   gets passed along.
+     * - A (short) string.
+     * - Some binary blob stored as a byte vector. During `effGetChunk` this
+     *   will contain some chunk data that should be written to
+     *   `Vst2PluginBridge::chunk_data`.
+     * - A specific struct in response to an event such as `audioMasterGetTime`
+     *   or `audioMasterIOChanged`.
+     * - An X11 window pointer for the editor window.
+     *
+     * @relates passthrough_event
+     */
+    using Payload = std::variant<std::nullptr_t,
+                                 std::string,
+                                 AEffect,
+                                 ChunkData,
+                                 DynamicSpeakerArrangement,
+                                 VstIOProperties,
+                                 VstMidiKeyName,
+                                 VstParameterProperties,
+                                 VstRect,
+                                 VstTimeInfo>;
+
+    /**
+     * The result that should be returned from the dispatch function.
+     */
+    native_intptr_t return_value;
+    /**
+     * Events typically either just return their return value or write a string
+     * into the void pointer, but sometimes an event response should forward
+     * some kind of special struct.
+     */
+    Payload payload;
+    /**
+     * The same as the above value, but for returning values written to the
+     * `intptr_t` value parameter. This is only used during
+     * `effGetSpeakerArrangement`.
+     */
+    std::optional<Payload> value_payload;
+
+    template <typename S>
+    void serialize(S& s) {
+        s.value8b(return_value);
+
+        s.object(payload);
+        s.ext(value_payload, bitsery::ext::StdOptional(),
+              [](S& s, auto& v) { s.object(v); });
+    }
+};
 
 template <typename S>
-void serialize(S& s, EventResultPayload& payload) {
+void serialize(S& s, Vst2EventResult::Payload& payload) {
     s.ext(payload,
           bitsery::ext::StdVariant{
               [](S&, std::nullptr_t&) {},
@@ -474,37 +505,6 @@ void serialize(S& s, EventResultPayload& payload) {
               [](S& s, VstTimeInfo& time_info) { s.object(time_info); }});
 }
 
-/**
- * AN instance of this should be sent back as a response to an incoming event.
- */
-struct Vst2EventResult {
-    /**
-     * The result that should be returned from the dispatch function.
-     */
-    native_intptr_t return_value;
-    /**
-     * Events typically either just return their return value or write a string
-     * into the void pointer, but sometimes an event response should forward
-     * some kind of special struct.
-     */
-    EventResultPayload payload;
-    /**
-     * The same as the above value, but for returning values written to the
-     * `intptr_t` value parameter. This is only used during
-     * `effGetSpeakerArrangement`.
-     */
-    std::optional<EventResultPayload> value_payload;
-
-    template <typename S>
-    void serialize(S& s) {
-        s.value8b(return_value);
-
-        s.object(payload);
-        s.ext(value_payload, bitsery::ext::StdOptional(),
-              [](S& s, auto& v) { s.object(v); });
-    }
-};
-
 /**
  * Represents a call to either `getParameter` or `setParameter`, depending on
  * whether `value` contains a value or not.