Add support for VST2 effBeginLoad{Bank,Program}

A user reported that REAPER was using these on the REAPER forum, but I
have not been able to reproduce that. And they went MIA after posting
about it. But hopefully this helps.

src/common/communication/vst2.h

@@ -504,6 +504,7 @@ Vst2EventResult passthrough_event(AEffect* plugin,
         [](VstIOProperties& props) -> void* { return &props; },
         [](VstMidiKeyName& key_name) -> void* { return &key_name; },
         [](VstParameterProperties& props) -> void* { return &props; },
+        [](VstPatchChunkInfo& info) -> void* { return &info; },
         [&](const WantsVstRect&) -> void* { return string_buffer.data(); },
         [](const WantsVstTimeInfo&) -> void* { return nullptr; },
         [&](const WantsString&) -> void* { return string_buffer.data(); }};

src/common/logging/vst2.cpp

@@ -445,6 +445,10 @@ void Vst2Logger::log_event(
                 [&](const VstParameterProperties&) {
                     message << "<writable_buffer>";
                 },
+                [&](const VstPatchChunkInfo& info) {
+                    message << "<patch_chunk_info for " << info.numElements
+                            << " banks/programs>";
+                },
                 [&](const WantsAEffectUpdate&) { message << "nullptr"; },
                 [&](const WantsAudioShmBufferConfig&) { message << "nullptr"; },
                 [&](const WantsChunkBuffer&) {

src/common/serialization/vst2.h

@@ -444,6 +444,7 @@ struct Vst2Event {
                                  VstIOProperties,
                                  VstMidiKeyName,
                                  VstParameterProperties,
+                                 VstPatchChunkInfo,
                                  WantsVstRect,
                                  WantsVstTimeInfo,
                                  WantsString>;
@@ -642,6 +643,15 @@ void serialize(S& s, VstParameterProperties& props) {
     s.container1b(props.future);
 }
 
+template <typename S>
+void serialize(S& s, VstPatchChunkInfo& info) {
+    s.value4b(info.version);
+    s.value4b(info.pluginUniqueID);
+    s.value4b(info.pluginVersion);
+    s.value4b(info.numElements);
+    s.container1b(info.future);
+}
+
 template <typename S>
 void serialize(S& s, VstRect& rect) {
     s.value2b(rect.top);

src/plugin/bridges/vst2.cpp

@@ -266,6 +266,10 @@ class DispatchDataConverter : public DefaultDataConverter {
                 return ChunkData{
                     std::vector<uint8_t>(chunk_data, chunk_data + value)};
             } break;
+            case effBeginLoadBank:
+            case effBeginLoadProgram:
+                return *static_cast<const VstPatchChunkInfo*>(data);
+                break;
             case effProcessEvents:
                 return DynamicVstEvents(*static_cast<const VstEvents*>(data));
                 break;

src/wine-host/bridges/vst2.cpp

@@ -102,7 +102,8 @@ static const std::unordered_set<int> safe_mutually_recursive_requests{
 static const std::unordered_set<int> unsafe_requests{
     effOpen,          effClose,       effEditGetRect,   effEditOpen,
     effEditClose,     effEditIdle,    effEditTop,       effMainsChanged,
-    effGetChunk,  effSetChunk, effSetSampleRate, effSetBlockSize};
+    effGetChunk,      effSetChunk,    effBeginLoadBank, effBeginLoadProgram,
+    effSetSampleRate, effSetBlockSize};
 
 /**
  * These opcodes from `unsafe_requests` should be run under realtime scheduling
@@ -622,8 +623,7 @@ class HostCallbackDataConverter : public DefaultDataConverter {
         return DefaultDataConverter::write_value(opcode, value, response);
     }
 
-    Vst2EventResult send_event(
+    Vst2EventResult send_event(asio::local::stream_protocol::socket& socket,
-        asio::local::stream_protocol::socket& socket,
                                const Vst2Event& event,
                                SerializationBufferBase& buffer) const override {
         if (mutually_recursive_callbacks.contains(event.opcode)) {