// yabridge: a Wine VST bridge
// Copyright (C) 2020 Robbert van der Helm
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see .
#include "vst2.h"
#include "../../common/communication/vst2.h"
#include "../utils.h"
// I'd rather use std::filesystem instead, but Boost.Process depends on
// boost::filesystem
namespace fs = boost::filesystem;
intptr_t dispatch_proxy(AEffect*, int, int, intptr_t, void*, float);
void process_proxy(AEffect*, float**, float**, int);
void process_replacing_proxy(AEffect*, float**, float**, int);
void process_double_replacing_proxy(AEffect*, double**, double**, int);
void set_parameter_proxy(AEffect*, int, float);
float get_parameter_proxy(AEffect*, int);
/**
* Fetch the bridge instance stored in an unused pointer from a VST plugin. This
* is sadly needed as a workaround to avoid using globals since we need free
* function pointers to interface with the VST C API.
*/
Vst2PluginBridge& get_bridge_instance(const AEffect& plugin) {
return *static_cast(plugin.ptr3);
}
Vst2PluginBridge::Vst2PluginBridge(audioMasterCallback host_callback)
: PluginBridge(PluginType::vst2,
find_vst_plugin(),
[](boost::asio::io_context& io_context) {
return Vst2Sockets(
io_context,
generate_endpoint_base(find_vst_plugin()
.filename()
.replace_extension("")
.string()),
true);
}),
// All the fields should be zero initialized because
// `Vst2PluginInstance::vstAudioMasterCallback` from Bitwig's plugin
// bridge will crash otherwise
plugin(),
host_callback_function(host_callback),
// TODO: This is UB, use composition with `generic_logger` instead
logger(static_cast(Logger::create_from_environment(
create_logger_prefix(sockets.base_dir)))) {
log_init_message();
// TODO: Also move his to `PluginHost`
#ifndef WITH_WINEDBG
// If the Wine process fails to start, then nothing will connect to the
// sockets and we'll be hanging here indefinitely. To prevent this, we'll
// periodically poll whether the Wine process is still running, and throw
// when it is not. The alternative would be to rewrite this to using
// `async_accept`, Boost.Asio timers, and another IO context, but I feel
// like this a much simpler solution.
host_guard_handler = std::jthread([&](std::stop_token st) {
using namespace std::literals::chrono_literals;
while (!st.stop_requested()) {
if (!plugin_host->running()) {
logger.log(
"The Wine host process has exited unexpectedly. Check the "
"output above for more information.");
std::terminate();
}
std::this_thread::sleep_for(20ms);
}
});
#endif
// This will block until all sockets have been connected to by the Wine VST
// host
sockets.connect();
#ifndef WITH_WINEDBG
host_guard_handler.request_stop();
#endif
// Set up all pointers for our `AEffect` struct. We will fill this with data
// from the VST plugin loaded in Wine at the end of this constructor.
plugin.ptr3 = this;
plugin.dispatcher = dispatch_proxy;
plugin.process = process_proxy;
plugin.setParameter = set_parameter_proxy;
plugin.getParameter = get_parameter_proxy;
plugin.processReplacing = process_replacing_proxy;
plugin.processDoubleReplacing = process_double_replacing_proxy;
// For our communication we use simple threads and blocking operations
// instead of asynchronous IO since communication has to be handled in
// lockstep anyway
host_callback_handler = std::jthread([&]() {
sockets.vst_host_callback.receive_events(
std::pair(logger, false),
[&](Event& event, bool /*on_main_thread*/) {
// MIDI events sent from the plugin back to the host are a
// special case here. They have to sent during the
// `processReplacing()` function or else the host will ignore
// them. Because of this we'll temporarily save any MIDI events
// we receive here, and then we'll actually send them to the
// host at the end of the `process_replacing()` function.
if (event.opcode == audioMasterProcessEvents) {
std::lock_guard lock(incoming_midi_events_mutex);
incoming_midi_events.push_back(
std::get(event.payload));
EventResult response{.return_value = 1,
.payload = nullptr,
.value_payload = std::nullopt};
return response;
} else {
return passthrough_event(&plugin, host_callback_function,
event);
}
});
});
// Read the plugin's information from the Wine process. This can only be
// done after we started accepting host callbacks as the plugin will likely
// call these during its initialization. Any further updates will be sent
// over the `dispatcher()` socket. This would happen whenever the plugin
// calls `audioMasterIOChanged()` and after the host calls `effOpen()`.
const auto initialization_data =
sockets.host_vst_control.receive_single();
const auto initialized_plugin =
std::get(initialization_data.payload);
// After receiving the `AEffect` values we'll want to send the configuration
// back to complete the startup process
sockets.host_vst_control.send(config);
update_aeffect(plugin, initialized_plugin);
}
class DispatchDataConverter : DefaultDataConverter {
public:
DispatchDataConverter(std::vector& chunk_data,
AEffect& plugin,
VstRect& editor_rectangle)
: chunk(chunk_data), plugin(plugin), rect(editor_rectangle) {}
EventPayload read(const int opcode,
const int index,
const intptr_t value,
const void* data) const override {
// There are some events that need specific structs that we can't simply
// serialize as a string because they might contain null bytes
switch (opcode) {
case effOpen:
// This should not be needed, but some improperly coded plugins
// such as the Roland Cloud plugins will initialize part of
// their `AEffect` only after the host calls `effOpen`, instead
// of during the initialization.
return WantsAEffectUpdate{};
break;
case effEditGetRect:
return WantsVstRect();
break;
case effEditOpen:
// The host will have passed us an X11 window handle in the void
// pointer. In the Wine VST host we'll create a Win32 window,
// ask the plugin to embed itself in that and then embed that
// window into this X11 window handle.
return reinterpret_cast(data);
break;
case effGetChunk:
return WantsChunkBuffer();
break;
case effSetChunk: {
const uint8_t* chunk_data = static_cast(data);
// When the host passes a chunk it will use the value parameter
// to tell us its length
return ChunkData{
std::vector(chunk_data, chunk_data + value)};
} break;
case effProcessEvents:
return DynamicVstEvents(*static_cast(data));
break;
case effGetInputProperties:
case effGetOutputProperties:
// In this case we can't simply pass an empty marker struct
// because the host can have already populated this field with
// data (or at least Bitwig does this)
return *static_cast(data);
break;
case effGetParameterProperties:
return *static_cast(data);
break;
case effGetMidiKeyName:
return *static_cast(data);
break;
case effSetSpeakerArrangement:
case effGetSpeakerArrangement:
// This is the output speaker configuration, the `read_value()`
// method below reads the input speaker configuration
return DynamicSpeakerArrangement(
*static_cast(data));
break;
// Any VST host I've encountered has properly zeroed out these their
// string buffers, but we'll add a list of opcodes that should
// return a string just in case `DefaultDataConverter::read()` can't
// figure it out.
case effGetProgramName:
case effGetParamLabel:
case effGetParamDisplay:
case effGetParamName:
case effGetProgramNameIndexed:
case effGetEffectName:
case effGetVendorString:
case effGetProductString:
case effShellGetNextPlugin:
return WantsString{};
break;
default:
return DefaultDataConverter::read(opcode, index, value, data);
break;
}
}
std::optional read_value(
const int opcode,
const intptr_t value) const override {
switch (opcode) {
case effSetSpeakerArrangement:
case effGetSpeakerArrangement:
// These two events are special in that they pass a pointer to
// the output speaker configuration through the `data`
// parameter, but then they also pass a pointer to the input
// speaker configuration through the `value` parameter. This is
// the only event that does this.
return DynamicSpeakerArrangement(
*static_cast(
reinterpret_cast(value)));
break;
default:
return DefaultDataConverter::read_value(opcode, value);
break;
}
}
void write(const int opcode,
void* data,
const EventResult& response) const override {
switch (opcode) {
case effOpen: {
// Update our `AEffect` object one last time for improperly
// coded late initialing plugins. Hopefully the host will see
// that the object is updated because these plugins don't send
// any notification about this.
const auto updated_plugin = std::get(response.payload);
update_aeffect(plugin, updated_plugin);
} break;
case effEditGetRect: {
// Either the plugin will have returned (a pointer to) their
// editor dimensions, or they will not have written anything.
if (std::holds_alternative(response.payload)) {
return;
}
const auto new_rect = std::get(response.payload);
rect = new_rect;
*static_cast(data) = ▭
} break;
case effGetChunk: {
// Write the chunk data to some publically accessible place in
// `Vst2PluginBridge` and write a pointer to that struct to the
// data pointer
const auto buffer =
std::get(response.payload).buffer;
chunk.assign(buffer.begin(), buffer.end());
*static_cast(data) = chunk.data();
} break;
case effGetInputProperties:
case effGetOutputProperties: {
// These opcodes pass the plugin some empty struct through the
// data parameter that the plugin then fills with flags and
// other data to describe an input or output channel.
const auto properties =
std::get(response.payload);
*static_cast(data) = properties;
} break;
case effGetParameterProperties: {
// Same as the above
const auto properties =
std::get(response.payload);
*static_cast(data) = properties;
} break;
case effGetMidiKeyName: {
// Ditto
const auto properties =
std::get(response.payload);
*static_cast(data) = properties;
} break;
case effGetSpeakerArrangement: {
// The plugin will have updated the objects passed by the host
// with its preferred output speaker configuration if it
// supports this. The same thing happens for the input speaker
// configuration in `write_value()`.
auto speaker_arrangement =
std::get(response.payload);
// Reconstruct a dynamically sized `VstSpeakerArrangement`
// object to a buffer, and write back the results to the data
// parameter.
VstSpeakerArrangement* output =
static_cast(data);
std::vector reconstructed_object =
speaker_arrangement.as_raw_data();
std::copy(reconstructed_object.begin(),
reconstructed_object.end(),
reinterpret_cast(output));
} break;
default:
DefaultDataConverter::write(opcode, data, response);
break;
}
}
intptr_t return_value(const int opcode,
const intptr_t original) const override {
return DefaultDataConverter::return_value(opcode, original);
}
void write_value(const int opcode,
intptr_t value,
const EventResult& response) const override {
switch (opcode) {
case effGetSpeakerArrangement: {
// Same as the above, but now for the input speaker
// configuration object under the `value` pointer
auto speaker_arrangement =
std::get(response.payload);
VstSpeakerArrangement* output =
static_cast(
reinterpret_cast(value));
std::vector reconstructed_object =
speaker_arrangement.as_raw_data();
std::copy(reconstructed_object.begin(),
reconstructed_object.end(),
reinterpret_cast(output));
} break;
default:
return DefaultDataConverter::write_value(opcode, value,
response);
break;
}
}
private:
std::vector& chunk;
AEffect& plugin;
VstRect& rect;
};
intptr_t Vst2PluginBridge::dispatch(AEffect* /*plugin*/,
int opcode,
int index,
intptr_t value,
void* data,
float option) {
// HACK: Ardour 5.X has a bug in its VST implementation where it calls the
// plugin's dispatcher before the plugin has even finished
// initializing. This has been fixed back in 2018, but there has not
// been a release that contains the fix yet. This should be removed
// once Ardour 6.0 gets released.
// https://tracker.ardour.org/view.php?id=7668
if (BOOST_UNLIKELY(plugin.magic == 0)) {
logger.log_event(true, opcode, index, value, nullptr, option,
std::nullopt);
logger.log(
" Warning: The host has dispatched an event before the plugin "
"has finished initializing, ignoring the event. (are we running "
"Ardour 5.X?)");
logger.log_event_response(true, opcode, 0, nullptr, std::nullopt);
return 0;
}
DispatchDataConverter converter(chunk_data, plugin, editor_rectangle);
switch (opcode) {
case effClose: {
// Allow the plugin to handle its own shutdown, and then terminate
// the process. Because terminating the Wine process will also
// forcefully close all open sockets this will also terminate our
// handler thread.
intptr_t return_value = 0;
try {
// TODO: Add some kind of timeout?
return_value = sockets.host_vst_dispatch.send_event(
converter, std::pair(logger, true),
opcode, index, value, data, option);
} catch (const boost::system::system_error& a) {
// Thrown when the socket gets closed because the VST plugin
// loaded into the Wine process crashed during shutdown
logger.log("The plugin crashed during shutdown, ignoring");
}
plugin_host->terminate();
// The `stop()` method will cause the IO context to just drop all of
// its work immediately and not throw any exceptions that would have
// been caused by pipes and sockets being closed.
io_context.stop();
delete this;
return return_value;
}; break;
case effCanDo: {
const std::string query(static_cast(data));
// NOTE: If the plugins returns `0xbeefXXXX` to this query, then
// REAPER will pass a libSwell handle rather than an X11
// window ID to `effEditOpen`. This is of course not going to
// work when the GUI is handled using Wine so we'll ignore it.
if (query == "hasCockosViewAsConfig") {
logger.log_event(true, opcode, index, value, query, option,
std::nullopt);
logger.log("");
logger.log(
" The host has requested libSwell GUI support, which is");
logger.log(" not supported when using Wine.");
logger.log(
" You can safely ignore this message; this is normal");
logger.log(" when using REAPER.");
logger.log("");
logger.log_event_response(true, opcode, -1, nullptr,
std::nullopt);
return -1;
}
} break;
}
// We don't reuse any buffers here like we do for audio processing. This
// would be useful for chunk data, but since that's only needed when saving
// and loading plugin state it's much better to have bitsery or our
// receiving function temporarily allocate a large enough buffer rather than
// to have a bunch of allocated memory sitting around doing nothing.
return sockets.host_vst_dispatch.send_event(
converter, std::pair(logger, true), opcode, index,
value, data, option);
}
template
void Vst2PluginBridge::do_process(T** inputs, T** outputs, int sample_frames) {
// The inputs and outputs arrays should be `[num_inputs][sample_frames]` and
// `[num_outputs][sample_frames]` floats large respectfully.
std::vector> input_buffers(plugin.numInputs,
std::vector(sample_frames));
for (int channel = 0; channel < plugin.numInputs; channel++) {
std::copy(inputs[channel], inputs[channel] + sample_frames,
input_buffers[channel].begin());
}
const AudioBuffers request{input_buffers, sample_frames};
sockets.host_vst_process_replacing.send(request, process_buffer);
// Write the results back to the `outputs` arrays
const auto response =
sockets.host_vst_process_replacing.receive_single(
process_buffer);
const auto& response_buffers =
std::get>>(response.buffers);
assert(response_buffers.size() == static_cast(plugin.numOutputs));
for (int channel = 0; channel < plugin.numOutputs; channel++) {
if constexpr (replacing) {
std::copy(response_buffers[channel].begin(),
response_buffers[channel].end(), outputs[channel]);
} else {
// The old `process()` function expects the plugin to add its output
// to the accumulated values in `outputs`. Since no host is ever
// going to call this anyways we won't even bother with a separate
// implementation and we'll just add `processReplacing()` results to
// `outputs`.
// We could use `std::execution::unseq` here but that would require
// linking to TBB and since this probably won't ever be used anyways
// that's a bit of a waste.
std::transform(response_buffers[channel].begin(),
response_buffers[channel].end(), outputs[channel],
outputs[channel],
[](const T& new_value, T& current_value) -> T {
return new_value + current_value;
});
}
}
// Plugins are allowed to send MIDI events during processing using a host
// callback. These have to be processed during the actual
// `processReplacing()` function or else the host will ignore them. To
// prevent these events from getting delayed by a sample we'll process them
// after the plugin is done processing audio rather than during the time
// we're still waiting on the plugin.
std::lock_guard lock(incoming_midi_events_mutex);
for (DynamicVstEvents& events : incoming_midi_events) {
host_callback_function(&plugin, audioMasterProcessEvents, 0, 0,
&events.as_c_events(), 0.0);
}
incoming_midi_events.clear();
}
void Vst2PluginBridge::process(AEffect* /*plugin*/,
float** inputs,
float** outputs,
int sample_frames) {
// Technically either `Vst2PluginBridge::process()` or
// `Vst2PluginBridge::process_replacing()` could actually call the other
// function on the plugin depending on what the plugin supports.
logger.log_trace(">> process() :: start");
do_process(inputs, outputs, sample_frames);
logger.log_trace(" process() :: end");
}
void Vst2PluginBridge::process_replacing(AEffect* /*plugin*/,
float** inputs,
float** outputs,
int sample_frames) {
logger.log_trace(">> processReplacing() :: start");
do_process(inputs, outputs, sample_frames);
logger.log_trace(" processReplacing() :: end");
}
void Vst2PluginBridge::process_double_replacing(AEffect* /*plugin*/,
double** inputs,
double** outputs,
int sample_frames) {
logger.log_trace(">> processDoubleReplacing() :: start");
do_process(inputs, outputs, sample_frames);
logger.log_trace(" processDoubleReplacing() :: end");
}
float Vst2PluginBridge::get_parameter(AEffect* /*plugin*/, int index) {
logger.log_get_parameter(index);
const Parameter request{index, std::nullopt};
ParameterResult response;
// Prevent race conditions from `getParameter()` and `setParameter()` being
// called at the same time since they share the same socket
{
std::lock_guard lock(parameters_mutex);
sockets.host_vst_parameters.send(request);
response =
sockets.host_vst_parameters.receive_single();
}
logger.log_get_parameter_response(*response.value);
return *response.value;
}
void Vst2PluginBridge::set_parameter(AEffect* /*plugin*/,
int index,
float value) {
logger.log_set_parameter(index, value);
const Parameter request{index, value};
ParameterResult response;
{
std::lock_guard lock(parameters_mutex);
sockets.host_vst_parameters.send(request);
response =
sockets.host_vst_parameters.receive_single();
}
logger.log_set_parameter_response();
// This should not contain any values and just serve as an acknowledgement
assert(!response.value);
}
// The below functions are proxy functions for the methods defined in
// `Bridge.cpp`
intptr_t dispatch_proxy(AEffect* plugin,
int opcode,
int index,
intptr_t value,
void* data,
float option) {
return get_bridge_instance(*plugin).dispatch(plugin, opcode, index, value,
data, option);
}
void process_proxy(AEffect* plugin,
float** inputs,
float** outputs,
int sample_frames) {
return get_bridge_instance(*plugin).process(plugin, inputs, outputs,
sample_frames);
}
void process_replacing_proxy(AEffect* plugin,
float** inputs,
float** outputs,
int sample_frames) {
return get_bridge_instance(*plugin).process_replacing(
plugin, inputs, outputs, sample_frames);
}
void process_double_replacing_proxy(AEffect* plugin,
double** inputs,
double** outputs,
int sample_frames) {
return get_bridge_instance(*plugin).process_double_replacing(
plugin, inputs, outputs, sample_frames);
}
void set_parameter_proxy(AEffect* plugin, int index, float value) {
return get_bridge_instance(*plugin).set_parameter(plugin, index, value);
}
float get_parameter_proxy(AEffect* plugin, int index) {
return get_bridge_instance(*plugin).get_parameter(plugin, index);
}