Carla/source/backend/plugin/LinuxSamplerPlugin.cpp

/*
 * Carla LinuxSampler Plugin
 * Copyright (C) 2011-2014 Filipe Coelho <falktx@falktx.com>
 *
 * 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 2 of
 * the License, or 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.
 *
 * For a full copy of the GNU General Public License see the doc/GPL.txt file.
 */

/* TODO
 * - implement buffer size changes
 * - implement sample rate changes
 * - call outDev->ReconnectAll() after changing buffer size or sample rate
 * - use CARLA_SAFE_ASSERT_RETURN with err
 */
#include "CarlaPluginInternal.hpp"
#include "CarlaEngine.hpp"

#ifdef WANT_LINUXSAMPLER

#include "CarlaBackendUtils.hpp"
#include "CarlaMathUtils.hpp"

#include "linuxsampler/EngineFactory.h"
#include <linuxsampler/Sampler.h>

#include <QtCore/QFileInfo>
#include <QtCore/QStringList>

namespace LinuxSampler {

using CarlaBackend::CarlaEngine;
using CarlaBackend::CarlaPlugin;

// -----------------------------------------------------------------------
// LinuxSampler static values

static const float kVolumeMax = 3.16227766f; // +10 dB
static const float kVolumeMin = 0.0f;        // -inf dB

// -----------------------------------------------------------------------
// LinuxSampler AudioOutputDevice Plugin

class AudioOutputDevicePlugin : public AudioOutputDevice
{
public:
    AudioOutputDevicePlugin(const CarlaEngine* const engine, const CarlaPlugin* const plugin, const bool uses16Outs)
        : AudioOutputDevice(std::map<String, DeviceCreationParameter*>()),
          fEngine(engine),
          fPlugin(plugin)
    {
        CARLA_ASSERT(engine != nullptr);
        CARLA_ASSERT(plugin != nullptr);

        AcquireChannels(uses16Outs ? 32 : 2);
    }

    ~AudioOutputDevicePlugin() override {}

    // -------------------------------------------------------------------
    // LinuxSampler virtual methods

    void Play() override
    {
    }

    bool IsPlaying() override
    {
        return (fEngine->isRunning() && fPlugin->isEnabled());
    }

    void Stop() override
    {
    }

    uint MaxSamplesPerCycle() override
    {
        return fEngine->getBufferSize();
    }

    uint SampleRate() override
    {
        return uint(fEngine->getSampleRate());
    }

    String Driver() override
    {
        return "AudioOutputDevicePlugin";
    }

    AudioChannel* CreateChannel(uint channelNr) override
    {
        return new AudioChannel(channelNr, nullptr, 0);
    }

    // -------------------------------------------------------------------
    // Give public access to the RenderAudio call

    int Render(const uint samples)
    {
        return RenderAudio(samples);
    }

    // -------------------------------------------------------------------

private:
    const CarlaEngine* const fEngine;
    const CarlaPlugin* const fPlugin;
};

// -----------------------------------------------------------------------
// LinuxSampler MidiInputPort Plugin

class MidiInputPortPlugin : public MidiInputPort
{
public:
    MidiInputPortPlugin(MidiInputDevice* const device, const int portNum)
        : MidiInputPort(device, portNum)
    {
    }

    ~MidiInputPortPlugin() override {}
};

// -----------------------------------------------------------------------
// LinuxSampler MidiInputDevice Plugin

class MidiInputDevicePlugin : public MidiInputDevice
{
public:
    MidiInputDevicePlugin(Sampler* const sampler)
        : MidiInputDevice(std::map<String, DeviceCreationParameter*>(), sampler)
    {
    }

    // -------------------------------------------------------------------
    // LinuxSampler virtual methods

    void Listen() override
    {
    }

    void StopListen() override
    {
    }

    String Driver() override
    {
        return "MidiInputDevicePlugin";
    }

    MidiInputPort* CreateMidiPort() override
    {
        return new MidiInputPortPlugin(this, int(Ports.size()));
    }

    MidiInputPortPlugin* CreateMidiPortPlugin()
    {
        return new MidiInputPortPlugin(this, int(Ports.size()));
    }
};

} // namespace LinuxSampler

// -----------------------------------------------------------------------

CARLA_BACKEND_START_NAMESPACE

#if 0
}
#endif

class LinuxSamplerPlugin : public CarlaPlugin
{
public:
    LinuxSamplerPlugin(CarlaEngine* const engine, const unsigned int id, const char* const format, const bool use16Outs)
        : CarlaPlugin(engine, id),
          fUses16Outs(use16Outs),
          fFormat(carla_strdup(format)),
          fLabel(nullptr),
          fMaker(nullptr),
          fRealName(nullptr),
          fEngine(nullptr),
          fAudioOutputDevice(nullptr),
          fMidiInputDevice(nullptr),
          fMidiInputPort(nullptr),
          fInstrument(nullptr)
    {
        carla_debug("LinuxSamplerPlugin::LinuxSamplerPlugin(%p, %i, %s, %s)", engine, id, format, bool2str(use16Outs));

        for (int i=0; i < MAX_MIDI_CHANNELS; ++i)
        {
            fCurMidiProgs[0]    = 0;
            fSamplerChannels[i] = nullptr;
            fEngineChannels[i]  = nullptr;
        }
    }

    ~LinuxSamplerPlugin() override
    {
        carla_debug("LinuxSamplerPlugin::~LinuxSamplerPlugin()");

        pData->singleMutex.lock();
        pData->masterMutex.lock();

        if (pData->client != nullptr && pData->client->isActive())
            pData->client->deactivate();

        if (pData->active)
        {
            deactivate();
            pData->active = false;
        }

        if (fEngine != nullptr)
        {
            if (fMidiInputDevice != nullptr)
            {
                if (fMidiInputPort != nullptr)
                {
                    for (int i=0; i < MAX_MIDI_CHANNELS; ++i)
                    {
                        if (fSamplerChannels[i] != nullptr)
                        {
                            if (fEngineChannels[i] != nullptr)
                            {
                                fMidiInputPort->Disconnect(fEngineChannels[i]);
                                fEngineChannels[i]->DisconnectAudioOutputDevice();
                                fEngineChannels[i] = nullptr;
                            }

                            fSampler.RemoveSamplerChannel(fSamplerChannels[i]);
                            fSamplerChannels[i] = nullptr;
                        }
                    }

                    delete fMidiInputPort;
                    fMidiInputPort = nullptr;
                }

                delete fMidiInputDevice;
                fMidiInputDevice = nullptr;
            }

            if (fAudioOutputDevice != nullptr)
            {
                delete fAudioOutputDevice;
                fAudioOutputDevice = nullptr;
            }

            fInstrument = nullptr;

            LinuxSampler::EngineFactory::Destroy(fEngine);
            fEngine = nullptr;
        }

        fInstrumentIds.clear();

        if (fFormat != nullptr)
        {
            delete[] fFormat;
            fFormat = nullptr;
        }

        if (fLabel != nullptr)
        {
            delete[] fLabel;
            fLabel = nullptr;
        }

        if (fMaker != nullptr)
        {
            delete[] fMaker;
            fMaker = nullptr;
        }

        if (fRealName != nullptr)
        {
            delete[] fRealName;
            fRealName = nullptr;
        }

        clearBuffers();
    }

    // -------------------------------------------------------------------
    // Information (base)

    PluginType getType() const noexcept override
    {
        return getPluginTypeFromString(fFormat);
    }

    PluginCategory getCategory() const noexcept override
    {
        return PLUGIN_CATEGORY_SYNTH;
    }

    // -------------------------------------------------------------------
    // Information (count)

    // nothing

    // -------------------------------------------------------------------
    // Information (current data)

    // nothing

    // -------------------------------------------------------------------
    // Information (per-plugin data)

    unsigned int getOptionsAvailable() const noexcept override
    {
        unsigned int options = 0x0;

        options |= PLUGIN_OPTION_MAP_PROGRAM_CHANGES;
        options |= PLUGIN_OPTION_SEND_CONTROL_CHANGES;
        options |= PLUGIN_OPTION_SEND_CHANNEL_PRESSURE;
        options |= PLUGIN_OPTION_SEND_PITCHBEND;
        options |= PLUGIN_OPTION_SEND_ALL_SOUND_OFF;

        return options;
    }

    void getLabel(char* const strBuf) const noexcept override
    {
        if (fLabel != nullptr)
            std::strncpy(strBuf, fLabel, STR_MAX);
        else
            CarlaPlugin::getLabel(strBuf);
    }

    void getMaker(char* const strBuf) const noexcept override
    {
        if (fMaker != nullptr)
            std::strncpy(strBuf, fMaker, STR_MAX);
        else
            CarlaPlugin::getMaker(strBuf);
    }

    void getCopyright(char* const strBuf) const noexcept override
    {
        getMaker(strBuf);
    }

    void getRealName(char* const strBuf) const noexcept override
    {
        if (fRealName != nullptr)
            std::strncpy(strBuf, fRealName, STR_MAX);
        else
            CarlaPlugin::getRealName(strBuf);
    }

    // -------------------------------------------------------------------
    // Set data (state)

    void prepareForSave() override
    {
        char strBuf[STR_MAX+1];
        std::snprintf(strBuf, STR_MAX, "%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i:%i", fCurMidiProgs[0],  fCurMidiProgs[1],  fCurMidiProgs[2],  fCurMidiProgs[3],
                                                                                          fCurMidiProgs[4],  fCurMidiProgs[5],  fCurMidiProgs[6],  fCurMidiProgs[7],
                                                                                          fCurMidiProgs[8],  fCurMidiProgs[9],  fCurMidiProgs[10], fCurMidiProgs[11],
                                                                                          fCurMidiProgs[12], fCurMidiProgs[13], fCurMidiProgs[14], fCurMidiProgs[15]);

        CarlaPlugin::setCustomData(CUSTOM_DATA_TYPE_STRING, "midiPrograms", strBuf, false);
    }

    // -------------------------------------------------------------------
    // Set data (internal stuff)

    void setCtrlChannel(const int8_t channel, const bool sendOsc, const bool sendCallback) noexcept override
    {
        if (channel < MAX_MIDI_CHANNELS)
            pData->midiprog.current = fCurMidiProgs[channel];

        CarlaPlugin::setCtrlChannel(channel, sendOsc, sendCallback);
    }

    // -------------------------------------------------------------------
    // Set data (plugin-specific stuff)

    void setCustomData(const char* const type, const char* const key, const char* const value, const bool sendGui) override
    {
        CARLA_SAFE_ASSERT_RETURN(type != nullptr && type[0] != '\0',);
        CARLA_SAFE_ASSERT_RETURN(key != nullptr && key[0] != '\0',);
        CARLA_SAFE_ASSERT_RETURN(value != nullptr && value[0] != '\0',);
        carla_debug("LinuxSamplerPlugin::setCustomData(%s, \"%s\", \"%s\", %s)", type, key, value, bool2str(sendGui));

        if (std::strcmp(type, CUSTOM_DATA_TYPE_STRING) != 0)
            return carla_stderr2("LinuxSamplerPlugin::setCustomData(\"%s\", \"%s\", \"%s\", %s) - type is not string", type, key, value, bool2str(sendGui));

        if (std::strcmp(key, "midiPrograms") != 0)
            return carla_stderr2("LinuxSamplerPlugin::setCustomData(\"%s\", \"%s\", \"%s\", %s) - type is not string", type, key, value, bool2str(sendGui));

        if (fUses16Outs)
        {
            QStringList midiProgramList(QString(value).split(":", QString::SkipEmptyParts));

            if (midiProgramList.count() == MAX_MIDI_CHANNELS)
            {
                uint i = 0;
                foreach (const QString& midiProg, midiProgramList)
                {
                    CARLA_SAFE_ASSERT_BREAK(i < MAX_MIDI_CHANNELS);

                    bool ok;
                    int index = midiProg.toInt(&ok);

                    if (ok && index >= 0 && index < static_cast<int>(pData->midiprog.count))
                    {
                        const uint32_t bank    = pData->midiprog.data[index].bank;
                        const uint32_t program = pData->midiprog.data[index].program;
                        const uint32_t rIndex  = bank*128 + program;

                        /*if (pData->engine->isOffline())
                        {
                            fEngineChannels[i]->PrepareLoadInstrument(pData->filename, rIndex);
                            fEngineChannels[i]->LoadInstrument();
                        }
                        else*/
                        {
                            fInstrument->LoadInstrumentInBackground(fInstrumentIds[rIndex], fEngineChannels[i]);
                        }

                        fCurMidiProgs[i] = index;

                        if (pData->ctrlChannel == static_cast<int32_t>(i))
                        {
                            pData->midiprog.current = index;
                            pData->engine->callback(ENGINE_CALLBACK_MIDI_PROGRAM_CHANGED, pData->id, index, 0, 0.0f, nullptr);
                        }
                    }

                    ++i;
                }

                CARLA_SAFE_ASSERT(i == MAX_MIDI_CHANNELS);
            }
        }

        CarlaPlugin::setCustomData(type, key, value, sendGui);
    }

    void setMidiProgram(const int32_t index, const bool sendGui, const bool sendOsc, const bool sendCallback) noexcept override
    {
        CARLA_SAFE_ASSERT_RETURN(index >= -1 && index < static_cast<int32_t>(pData->midiprog.count),);

        if (index >= 0 && pData->ctrlChannel >= 0 && pData->ctrlChannel < MAX_MIDI_CHANNELS)
        {
            const uint32_t bank    = pData->midiprog.data[index].bank;
            const uint32_t program = pData->midiprog.data[index].program;
            const uint32_t rIndex  = bank*128 + program;

            LinuxSampler::EngineChannel* const engineChannel(fEngineChannels[pData->ctrlChannel]);

            const ScopedSingleProcessLocker spl(this, (sendGui || sendOsc || sendCallback));

            /*if (pData->engine->isOffline())
            {
                engineChannel->PrepareLoadInstrument(pData->filename, rIndex);
                engineChannel->LoadInstrument();
            }
            else*/
            {
                try {
                    fInstrument->LoadInstrumentInBackground(fInstrumentIds[rIndex], engineChannel);
                } catch(...) {}
            }

            fCurMidiProgs[pData->ctrlChannel] = index;
        }

        CarlaPlugin::setMidiProgram(index, sendGui, sendOsc, sendCallback);
    }

    // -------------------------------------------------------------------
    // Set ui stuff

    // nothing

    // -------------------------------------------------------------------
    // Plugin state

    void reload() override
    {
        CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr,);
        CARLA_SAFE_ASSERT_RETURN(fInstrument != nullptr,);
        carla_debug("LinuxSamplerPlugin::reload() - start");

        const EngineProcessMode processMode(pData->engine->getProccessMode());

        // Safely disable plugin for reload
        const ScopedDisabler sd(this);

        if (pData->active)
            deactivate();

        clearBuffers();

        uint32_t aOuts;
        aOuts = fUses16Outs ? 32 : 2;

        pData->audioOut.createNew(aOuts);

        const uint portNameSize(pData->engine->getMaxPortNameSize());
        CarlaString portName;

        // ---------------------------------------
        // Audio Outputs

        if (fUses16Outs)
        {
            for (uint32_t i=0; i < 32; ++i)
            {
                portName.clear();

                if (processMode == ENGINE_PROCESS_MODE_SINGLE_CLIENT)
                {
                    portName  = pData->name;
                    portName += ":";
                }

                portName += "out-";

                if ((i+2)/2 < 9)
                    portName += "0";

                portName += CarlaString((i+2)/2);

                if (i % 2 == 0)
                    portName += "L";
                else
                    portName += "R";

                portName.truncate(portNameSize);

                pData->audioOut.ports[i].port   = (CarlaEngineAudioPort*)pData->client->addPort(kEnginePortTypeAudio, portName, false);
                pData->audioOut.ports[i].rindex = i;
            }
        }
        else
        {
            // out-left
            portName.clear();

            if (processMode == ENGINE_PROCESS_MODE_SINGLE_CLIENT)
            {
                portName  = pData->name;
                portName += ":";
            }

            portName += "out-left";
            portName.truncate(portNameSize);

            pData->audioOut.ports[0].port   = (CarlaEngineAudioPort*)pData->client->addPort(kEnginePortTypeAudio, portName, false);
            pData->audioOut.ports[0].rindex = 0;

            // out-right
            portName.clear();

            if (processMode == ENGINE_PROCESS_MODE_SINGLE_CLIENT)
            {
                portName  = pData->name;
                portName += ":";
            }

            portName += "out-right";
            portName.truncate(portNameSize);

            pData->audioOut.ports[1].port   = (CarlaEngineAudioPort*)pData->client->addPort(kEnginePortTypeAudio, portName, false);
            pData->audioOut.ports[1].rindex = 1;
        }

        // ---------------------------------------
        // Event Input

        {
            portName.clear();

            if (processMode == ENGINE_PROCESS_MODE_SINGLE_CLIENT)
            {
                portName  = pData->name;
                portName += ":";
            }

            portName += "events-in";
            portName.truncate(portNameSize);

            pData->event.portIn = (CarlaEngineEventPort*)pData->client->addPort(kEnginePortTypeEvent, portName, true);
        }

        // ---------------------------------------

        // plugin hints
        pData->hints  = 0x0;
        pData->hints |= PLUGIN_IS_SYNTH;
        pData->hints |= PLUGIN_CAN_VOLUME;

        if (! fUses16Outs)
            pData->hints |= PLUGIN_CAN_BALANCE;

        // extra plugin hints
        pData->extraHints  = 0x0;
        pData->extraHints |= PLUGIN_EXTRA_HINT_HAS_MIDI_IN;

        if (! fUses16Outs)
            pData->extraHints |= PLUGIN_EXTRA_HINT_CAN_RUN_RACK;

        bufferSizeChanged(pData->engine->getBufferSize());
        reloadPrograms(true);

        if (pData->active)
            activate();

        carla_debug("LinuxSamplerPlugin::reload() - end");
    }

    void reloadPrograms(bool doInit) override
    {
        carla_debug("LinuxSamplerPlugin::reloadPrograms(%s)", bool2str(doInit));

        // Delete old programs
        pData->midiprog.clear();

        // Query new programs
        uint32_t count = uint32_t(fInstrumentIds.size());

        // sound kits must always have at least 1 midi-program
        CARLA_SAFE_ASSERT_RETURN(count > 0,);

        pData->midiprog.createNew(count);

        // Update data
        LinuxSampler::InstrumentManager::instrument_info_t info;

        for (uint32_t i=0; i < pData->midiprog.count; ++i)
        {
            pData->midiprog.data[i].bank    = i / 128;
            pData->midiprog.data[i].program = i % 128;

            try {
                info = fInstrument->GetInstrumentInfo(fInstrumentIds[i]);
            }
            catch (const LinuxSampler::InstrumentManagerException&)
            {
                continue;
            }

            pData->midiprog.data[i].name = carla_strdup(info.InstrumentName.c_str());
        }

#ifndef BUILD_BRIDGE
        // Update OSC Names
        if (pData->engine->isOscControlRegistered())
        {
            pData->engine->oscSend_control_set_midi_program_count(pData->id, count);

            for (uint32_t i=0; i < count; ++i)
                pData->engine->oscSend_control_set_midi_program_data(pData->id, i, pData->midiprog.data[i].bank, pData->midiprog.data[i].program, pData->midiprog.data[i].name);
        }
#endif

        if (doInit)
        {
            for (int i=0; i < MAX_MIDI_CHANNELS; ++i)
            {
                CARLA_SAFE_ASSERT_CONTINUE(fEngineChannels[i] != nullptr);

                /*fEngineChannels[i]->PrepareLoadInstrument(pData->filename, 0);
                fEngineChannels[i]->LoadInstrument();*/
                fInstrument->LoadInstrumentInBackground(fInstrumentIds[0], fEngineChannels[i]);
                fCurMidiProgs[i] = 0;
            }

            pData->midiprog.current = 0;
        }
        else
        {
            pData->engine->callback(ENGINE_CALLBACK_RELOAD_PROGRAMS, pData->id, 0, 0, 0.0f, nullptr);
        }
    }

    // -------------------------------------------------------------------
    // Plugin processing

#if 0
    void activate() override
    {
        for (int i=0; i < MAX_MIDI_CHANNELS; ++i)
        {
            if (fAudioOutputDevices[i] != nullptr)
                fAudioOutputDevices[i]->Play();
        }
    }

    void deactivate() override
    {
        for (int i=0; i < MAX_MIDI_CHANNELS; ++i)
        {
            if (fAudioOutputDevices[i] != nullptr)
                fAudioOutputDevices[i]->Stop();
        }
    }
#endif

    void process(float** const, float** const outBuffer, const uint32_t frames) override
    {
        // --------------------------------------------------------------------------------------------------------
        // Check if active

        if (! pData->active)
        {
            // disable any output sound
            for (uint32_t i=0; i < pData->audioOut.count; ++i)
                FLOAT_CLEAR(outBuffer[i], frames);
            return;
        }

        // --------------------------------------------------------------------------------------------------------
        // Check if needs reset

        if (pData->needsReset)
        {
            if (pData->options & PLUGIN_OPTION_SEND_ALL_SOUND_OFF)
            {
                for (uint i=0; i < MAX_MIDI_CHANNELS; ++i)
                {
                    fMidiInputPort->DispatchControlChange(MIDI_CONTROL_ALL_NOTES_OFF, 0, i);
                    fMidiInputPort->DispatchControlChange(MIDI_CONTROL_ALL_SOUND_OFF, 0, i);
                }
            }
            else if (pData->ctrlChannel >= 0 && pData->ctrlChannel < MAX_MIDI_CHANNELS)
            {
                for (uint8_t i=0; i < MAX_MIDI_NOTE; ++i)
                    fMidiInputPort->DispatchNoteOff(i, 0, uint(pData->ctrlChannel));
            }

            pData->needsReset = false;
        }

        // --------------------------------------------------------------------------------------------------------
        // Event Input and Processing

        {
            // ----------------------------------------------------------------------------------------------------
            // MIDI Input (External)

            if (pData->extNotes.mutex.tryLock())
            {
                while (! pData->extNotes.data.isEmpty())
                {
                    const ExternalMidiNote& note(pData->extNotes.data.getFirst(true));

                    CARLA_SAFE_ASSERT_CONTINUE(note.channel >= 0 && note.channel < MAX_MIDI_CHANNELS);

                    if (note.velo > 0)
                        fMidiInputPort->DispatchNoteOn(note.note, note.velo, static_cast<uint>(note.channel));
                    else
                        fMidiInputPort->DispatchNoteOff(note.note, note.velo, static_cast<uint>(note.channel));
                }

                pData->extNotes.mutex.unlock();

            } // End of MIDI Input (External)

            // ----------------------------------------------------------------------------------------------------
            // Event Input (System)

            bool allNotesOffSent = false;
            bool sampleAccurate  = (pData->options & PLUGIN_OPTION_FIXED_BUFFERS) == 0;

            uint32_t nEvents = pData->event.portIn->getEventCount();
            uint32_t startTime  = 0;
            uint32_t timeOffset = 0;

            uint32_t nextBankIds[MAX_MIDI_CHANNELS] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 128, 0, 0, 0, 0, 0, 0 };

            if (pData->midiprog.current >= 0 && pData->midiprog.count > 0 && pData->ctrlChannel >= 0 && pData->ctrlChannel < MAX_MIDI_CHANNELS)
                nextBankIds[pData->ctrlChannel] = pData->midiprog.data[pData->midiprog.current].bank;

            for (uint32_t i=0; i < nEvents; ++i)
            {
                const EngineEvent& event(pData->event.portIn->getEvent(i));

                CARLA_SAFE_ASSERT_CONTINUE(event.time < frames);
                CARLA_SAFE_ASSERT_BREAK(event.time >= timeOffset);

                if (event.time > timeOffset && sampleAccurate)
                {
                    if (processSingle(outBuffer, event.time - timeOffset, timeOffset))
                    {
                        startTime  = 0;
                        timeOffset = event.time;

                        if (pData->midiprog.current >= 0 && pData->midiprog.count > 0 && pData->ctrlChannel >= 0 && pData->ctrlChannel < MAX_MIDI_CHANNELS)
                            nextBankIds[pData->ctrlChannel] = pData->midiprog.data[pData->midiprog.current].bank;
                    }
                    else
                        startTime += timeOffset;
                }

                // Control change
                switch (event.type)
                {
                case kEngineEventTypeNull:
                    break;

                case kEngineEventTypeControl:
                {
                    const EngineControlEvent& ctrlEvent = event.ctrl;

                    switch (ctrlEvent.type)
                    {
                    case kEngineControlEventTypeNull:
                        break;

                    case kEngineControlEventTypeParameter:
                    {
#ifndef BUILD_BRIDGE
                        // Control backend stuff
                        if (event.channel == pData->ctrlChannel)
                        {
                            float value;

                            if (MIDI_IS_CONTROL_BREATH_CONTROLLER(ctrlEvent.param) && (pData->hints & PLUGIN_CAN_DRYWET) != 0)
                            {
                                value = ctrlEvent.value;
                                setDryWet(value, false, false);
                                pData->postponeRtEvent(kPluginPostRtEventParameterChange, PARAMETER_DRYWET, 0, value);
                            }

                            if (MIDI_IS_CONTROL_CHANNEL_VOLUME(ctrlEvent.param) && (pData->hints & PLUGIN_CAN_VOLUME) != 0)
                            {
                                value = ctrlEvent.value*127.0f/100.0f;
                                setVolume(value, false, false);
                                pData->postponeRtEvent(kPluginPostRtEventParameterChange, PARAMETER_VOLUME, 0, value);
                            }

                            if (MIDI_IS_CONTROL_BALANCE(ctrlEvent.param) && (pData->hints & PLUGIN_CAN_BALANCE) != 0)
                            {
                                float left, right;
                                value = ctrlEvent.value/0.5f - 1.0f;

                                if (value < 0.0f)
                                {
                                    left  = -1.0f;
                                    right = (value*2.0f)+1.0f;
                                }
                                else if (value > 0.0f)
                                {
                                    left  = (value*2.0f)-1.0f;
                                    right = 1.0f;
                                }
                                else
                                {
                                    left  = -1.0f;
                                    right = 1.0f;
                                }

                                setBalanceLeft(left, false, false);
                                setBalanceRight(right, false, false);
                                pData->postponeRtEvent(kPluginPostRtEventParameterChange, PARAMETER_BALANCE_LEFT, 0, left);
                                pData->postponeRtEvent(kPluginPostRtEventParameterChange, PARAMETER_BALANCE_RIGHT, 0, right);
                            }
                        }
#endif

                        // Control plugin parameters
                        for (uint32_t k=0; k < pData->param.count; ++k)
                        {
                            if (pData->param.data[k].midiChannel != event.channel)
                                continue;
                            if (pData->param.data[k].midiCC != ctrlEvent.param)
                                continue;
                            if (pData->param.data[k].hints != PARAMETER_INPUT)
                                continue;
                            if ((pData->param.data[k].hints & PARAMETER_IS_AUTOMABLE) == 0)
                                continue;

                            float value;

                            if (pData->param.data[k].hints & PARAMETER_IS_BOOLEAN)
                            {
                                value = (ctrlEvent.value < 0.5f) ? pData->param.ranges[k].min : pData->param.ranges[k].max;
                            }
                            else
                            {
                                value = pData->param.ranges[k].getUnnormalizedValue(ctrlEvent.value);

                                if (pData->param.data[k].hints & PARAMETER_IS_INTEGER)
                                    value = std::rint(value);
                            }

                            setParameterValue(k, value, false, false, false);
                            pData->postponeRtEvent(kPluginPostRtEventParameterChange, static_cast<int32_t>(k), 0, value);
                        }

                        if ((pData->options & PLUGIN_OPTION_SEND_CONTROL_CHANGES) != 0 && ctrlEvent.param <= 0x5F)
                        {
                            fMidiInputPort->DispatchControlChange(uint8_t(ctrlEvent.param), uint8_t(ctrlEvent.value*127.0f), event.channel, static_cast<int32_t>(sampleAccurate ? startTime : event.time));
                        }

                        break;
                    }

                    case kEngineControlEventTypeMidiBank:
                        if (event.channel < MAX_MIDI_CHANNELS && (pData->options & PLUGIN_OPTION_MAP_PROGRAM_CHANGES) != 0)
                            nextBankIds[event.channel] = ctrlEvent.param;
                        break;

                    case kEngineControlEventTypeMidiProgram:
                        if (event.channel < MAX_MIDI_CHANNELS && (pData->options & PLUGIN_OPTION_MAP_PROGRAM_CHANGES) != 0)
                        {
                            const uint32_t bankId(nextBankIds[event.channel]);
                            const uint32_t progId(ctrlEvent.param);
                            const uint32_t rIndex = bankId*128 + progId;

                            for (uint32_t k=0; k < pData->midiprog.count; ++k)
                            {
                                if (pData->midiprog.data[k].bank == bankId && pData->midiprog.data[k].program == progId)
                                {
                                    LinuxSampler::EngineChannel* const engineChannel(fEngineChannels[pData->ctrlChannel]);

                                    /*if (pData->engine->isOffline())
                                    {
                                        engineChannel->PrepareLoadInstrument(pData->filename, rIndex);
                                        engineChannel->LoadInstrument();
                                    }
                                    else*/
                                    {
                                        fInstrument->LoadInstrumentInBackground(fInstrumentIds[rIndex], engineChannel);
                                    }

                                    fCurMidiProgs[event.channel] = static_cast<int32_t>(k);

                                    if (event.channel == pData->ctrlChannel)
                                        pData->postponeRtEvent(kPluginPostRtEventMidiProgramChange, static_cast<int32_t>(k), 0, 0.0f);

                                    break;
                                }
                            }
                        }
                        break;

                    case kEngineControlEventTypeAllSoundOff:
                        if (pData->options & PLUGIN_OPTION_SEND_ALL_SOUND_OFF)
                        {
                            fMidiInputPort->DispatchControlChange(MIDI_CONTROL_ALL_SOUND_OFF, 0, event.channel, static_cast<int32_t>(sampleAccurate ? startTime : event.time));
                        }
                        break;

                    case kEngineControlEventTypeAllNotesOff:
                        if (pData->options & PLUGIN_OPTION_SEND_ALL_SOUND_OFF)
                        {
                            if (event.channel == pData->ctrlChannel && ! allNotesOffSent)
                            {
                                allNotesOffSent = true;
                                sendMidiAllNotesOffToCallback();
                            }

                            fMidiInputPort->DispatchControlChange(MIDI_CONTROL_ALL_NOTES_OFF, 0, event.channel, static_cast<int32_t>(sampleAccurate ? startTime : event.time));
                        }
                        break;
                    }
                    break;
                }

                case kEngineEventTypeMidi:
                {
                    const EngineMidiEvent& midiEvent(event.midi);

                    uint8_t status  = uint8_t(MIDI_GET_STATUS_FROM_DATA(midiEvent.data));
                    uint8_t channel = event.channel;

                    // Fix bad note-off
                    if (MIDI_IS_STATUS_NOTE_ON(status) && midiEvent.data[2] == 0)
                        status = MIDI_STATUS_NOTE_OFF;

                    if (MIDI_IS_STATUS_POLYPHONIC_AFTERTOUCH(status) && (pData->options & PLUGIN_OPTION_SEND_NOTE_AFTERTOUCH) == 0)
                        continue;
                    if (MIDI_IS_STATUS_CONTROL_CHANGE(status) && (pData->options & PLUGIN_OPTION_SEND_CONTROL_CHANGES) == 0)
                        continue;
                    if (MIDI_IS_STATUS_CHANNEL_PRESSURE(status) && (pData->options & PLUGIN_OPTION_SEND_CHANNEL_PRESSURE) == 0)
                        continue;
                    if (MIDI_IS_STATUS_PITCH_WHEEL_CONTROL(status) && (pData->options & PLUGIN_OPTION_SEND_PITCHBEND) == 0)
                        continue;

                    // put back channel in data
                    uint8_t data[EngineMidiEvent::kDataSize];
                    std::memcpy(data, event.midi.data, EngineMidiEvent::kDataSize);

                    if (status < 0xF0 && channel < MAX_MIDI_CHANNELS)
                        data[0] = uint8_t(data[0] + channel);

                    fMidiInputPort->DispatchRaw(data, static_cast<int32_t>(sampleAccurate ? startTime : event.time));

                    if (status == MIDI_STATUS_NOTE_ON)
                        pData->postponeRtEvent(kPluginPostRtEventNoteOn, channel, data[1], data[2]);
                    else if (status == MIDI_STATUS_NOTE_OFF)
                        pData->postponeRtEvent(kPluginPostRtEventNoteOff, channel,data[1], 0.0f);

                    break;
                }
                }
            }

            pData->postRtEvents.trySplice();

            if (frames > timeOffset)
                processSingle(outBuffer, frames - timeOffset, timeOffset);

        } // End of Event Input and Processing
    }

    bool processSingle(float** const outBuffer, const uint32_t frames, const uint32_t timeOffset)
    {
        CARLA_SAFE_ASSERT_RETURN(outBuffer != nullptr, false);
        CARLA_SAFE_ASSERT_RETURN(frames > 0, false);

        // --------------------------------------------------------------------------------------------------------
        // Try lock, silence otherwise

        if (pData->engine->isOffline())
        {
            pData->singleMutex.lock();
        }
        else if (! pData->singleMutex.tryLock())
        {
            for (uint32_t i=0; i < pData->audioOut.count; ++i)
            {
                for (uint32_t k=0; k < frames; ++k)
                    outBuffer[i][k+timeOffset] = 0.0f;
            }

            return false;
        }

        // --------------------------------------------------------------------------------------------------------
        // Run plugin

        for (uint32_t i=0; i < pData->audioOut.count; ++i)
        {
            if (LinuxSampler::AudioChannel* const outDev = fAudioOutputDevice->Channel(i))
                outDev->SetBuffer(outBuffer[i] + timeOffset);
        }

        fAudioOutputDevice->Render(frames);

#ifndef BUILD_BRIDGE
        // --------------------------------------------------------------------------------------------------------
        // Post-processing (dry/wet, volume and balance)

        {
            const bool doVolume  = (pData->hints & PLUGIN_CAN_VOLUME) > 0 && pData->postProc.volume != 1.0f;
            const bool doBalance = (pData->hints & PLUGIN_CAN_BALANCE) > 0 && (pData->postProc.balanceLeft != -1.0f || pData->postProc.balanceRight != 1.0f);

            float oldBufLeft[doBalance ? frames : 1];

            for (uint32_t i=0; i < pData->audioOut.count; ++i)
            {
                // Balance
                if (doBalance)
                {
                    if (i % 2 == 0)
                        FLOAT_COPY(oldBufLeft, outBuffer[i], frames);

                    float balRangeL = (pData->postProc.balanceLeft  + 1.0f)/2.0f;
                    float balRangeR = (pData->postProc.balanceRight + 1.0f)/2.0f;

                    for (uint32_t k=0; k < frames; ++k)
                    {
                        if (i % 2 == 0)
                        {
                            // left
                            outBuffer[i][k]  = oldBufLeft[k]     * (1.0f - balRangeL);
                            outBuffer[i][k] += outBuffer[i+1][k] * (1.0f - balRangeR);
                        }
                        else
                        {
                            // right
                            outBuffer[i][k]  = outBuffer[i][k] * balRangeR;
                            outBuffer[i][k] += oldBufLeft[k]   * balRangeL;
                        }
                    }
                }

                // Volume
                if (doVolume)
                {
                    for (uint32_t k=0; k < frames; ++k)
                        outBuffer[i][k+timeOffset] *= pData->postProc.volume;
                }
            }

        } // End of Post-processing
#endif

        // --------------------------------------------------------------------------------------------------------

        pData->singleMutex.unlock();
        return true;
    }

#ifndef CARLA_OS_WIN // FIXME, need to update linuxsampler win32 build
    void bufferSizeChanged(const uint32_t) override
    {
        CARLA_SAFE_ASSERT_RETURN(fAudioOutputDevice != nullptr,);

        fAudioOutputDevice->ReconnectAll();
    }

    void sampleRateChanged(const double) override
    {
        CARLA_SAFE_ASSERT_RETURN(fAudioOutputDevice != nullptr,);

        fAudioOutputDevice->ReconnectAll();
    }
#endif

    // -------------------------------------------------------------------
    // Plugin buffers

    // nothing

    // -------------------------------------------------------------------

    const void* getExtraStuff() const noexcept override
    {
        static const char xtrue[]  = "true";
        static const char xfalse[] = "false";
        return fUses16Outs ? xtrue : xfalse;
    }

    bool init(const char* const filename, const char* const name, const char* const label)
    {
        CARLA_SAFE_ASSERT_RETURN(pData->engine != nullptr, false);

        // ---------------------------------------------------------------
        // first checks

        if (pData->client != nullptr)
        {
            pData->engine->setLastError("Plugin client is already registered");
            return false;
        }

        if (filename == nullptr || filename[0] == '\0')
        {
            pData->engine->setLastError("null filename");
            return false;
        }

        if (label == nullptr || label[0] == '\0')
        {
            pData->engine->setLastError("null label");
            return false;
        }

        // ---------------------------------------------------------------
        // Store format

        CarlaString cstype(fFormat);
        cstype.toLower();
        const char* const ctype(cstype.getBuffer());

        // ---------------------------------------------------------------
        // Create the LinuxSampler Engine

        try {
            fEngine = LinuxSampler::EngineFactory::Create(ctype);
        }
        catch (LinuxSampler::Exception& e)
        {
            pData->engine->setLastError(e.what());
            return false;
        }

        // ---------------------------------------------------------------
        // Init LinuxSampler stuff

        fAudioOutputDevice = new LinuxSampler::AudioOutputDevicePlugin(pData->engine, this, fUses16Outs);

        fMidiInputDevice = new LinuxSampler::MidiInputDevicePlugin(&fSampler);
        fMidiInputPort   = fMidiInputDevice->CreateMidiPortPlugin();

        for (uint i=0; i < MAX_MIDI_CHANNELS; ++i)
        {
            fSamplerChannels[i] = fSampler.AddSamplerChannel();
            CARLA_SAFE_ASSERT_CONTINUE(fSamplerChannels[i] != nullptr);

            fSamplerChannels[i]->SetEngineType(ctype);
            fSamplerChannels[i]->SetAudioOutputDevice(fAudioOutputDevice);

            fEngineChannels[i] = fSamplerChannels[i]->GetEngineChannel();
            CARLA_SAFE_ASSERT_CONTINUE(fEngineChannels[i] != nullptr);

            fEngineChannels[i]->Connect(fAudioOutputDevice);
            fEngineChannels[i]->Volume(LinuxSampler::kVolumeMax);

            if (fUses16Outs)
            {
                fEngineChannels[i]->SetOutputChannel(0, i*2);
                fEngineChannels[i]->SetOutputChannel(1, i*2 +1);
            }
            else
            {
                fEngineChannels[i]->SetOutputChannel(0, 0);
                fEngineChannels[i]->SetOutputChannel(1, 1);
            }

            fMidiInputPort->Connect(fEngineChannels[i], static_cast<LinuxSampler::midi_chan_t>(i));
        }

        // ---------------------------------------------------------------
        // Get the Engine's Instrument Manager

        fInstrument = fEngine->GetInstrumentManager();

        if (fInstrument == nullptr)
        {
            pData->engine->setLastError("Failed to get LinuxSampler instrument manager");
            return false;
        }

        // ---------------------------------------------------------------
        // Load the Instrument via filename

        try {
            fInstrumentIds = fInstrument->GetInstrumentFileContent(filename);
        }
        catch (const LinuxSampler::InstrumentManagerException& e)
        {
            pData->engine->setLastError(e.what());
            return false;
        }

        // ---------------------------------------------------------------
        // Get info

        if (fInstrumentIds.size() == 0)
        {
            pData->engine->setLastError("Failed to find any instruments");
            return false;
        }

        LinuxSampler::InstrumentManager::instrument_info_t info;

        try {
            info = fInstrument->GetInstrumentInfo(fInstrumentIds[0]);
        }
        catch (const LinuxSampler::InstrumentManagerException& e)
        {
            pData->engine->setLastError(e.what());
            return false;
        }

        CarlaString label2(label);

        if (fUses16Outs && ! label2.endsWith(" (16 outs)"))
            label2 += " (16 outs)";

        fLabel    = label2.dup();
        fMaker    = carla_strdup(info.Artists.c_str());
        fRealName = carla_strdup(info.InstrumentName.c_str());

        pData->filename = carla_strdup(filename);

        if (name != nullptr && name[0] != '\0')
            pData->name = pData->engine->getUniquePluginName(name);
        else if (fRealName[0] != '\0')
            pData->name = pData->engine->getUniquePluginName(fRealName);
        else
            pData->name = pData->engine->getUniquePluginName(label);

        // ---------------------------------------------------------------
        // register client

        pData->client = pData->engine->addClient(this);

        if (pData->client == nullptr || ! pData->client->isOk())
        {
            pData->engine->setLastError("Failed to register plugin client");
            return false;
        }

        // ---------------------------------------------------------------
        // load plugin settings

        {
            // set default options
            pData->options = 0x0;

            pData->options |= PLUGIN_OPTION_MAP_PROGRAM_CHANGES;
            pData->options |= PLUGIN_OPTION_SEND_CHANNEL_PRESSURE;
            pData->options |= PLUGIN_OPTION_SEND_PITCHBEND;
            pData->options |= PLUGIN_OPTION_SEND_ALL_SOUND_OFF;

            // set identifier string
            CarlaString identifier(fFormat);
            identifier += "/";

            if (const char* const shortname = std::strrchr(filename, OS_SEP))
                identifier += shortname+1;
            else
                identifier += label;

            pData->identifier = identifier.dup();

            // load settings
            pData->options = pData->loadSettings(pData->options, getOptionsAvailable());
        }

        return true;
    }

    // -------------------------------------------------------------------

private:
    const bool  fUses16Outs;
    const char* fFormat;
    const char* fLabel;
    const char* fMaker;
    const char* fRealName;

    int32_t fCurMidiProgs[MAX_MIDI_CHANNELS];

    LinuxSampler::Sampler fSampler;
    LinuxSampler::Engine* fEngine;

    LinuxSampler::SamplerChannel* fSamplerChannels[MAX_MIDI_CHANNELS];
    LinuxSampler::EngineChannel*  fEngineChannels[MAX_MIDI_CHANNELS];

    LinuxSampler::AudioOutputDevicePlugin* fAudioOutputDevice;
    LinuxSampler::MidiInputDevicePlugin*   fMidiInputDevice;
    LinuxSampler::MidiInputPortPlugin*     fMidiInputPort;

    LinuxSampler::InstrumentManager* fInstrument;
    std::vector<LinuxSampler::InstrumentManager::instrument_id_t> fInstrumentIds;

    CARLA_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(LinuxSamplerPlugin)
};

CARLA_BACKEND_END_NAMESPACE

#endif // WANT_LINUXSAMPLER

CARLA_BACKEND_START_NAMESPACE

CarlaPlugin* CarlaPlugin::newLinuxSampler(const Initializer& init, const char* const format, const bool use16Outs)
{
    carla_debug("LinuxSamplerPlugin::newLinuxSampler({%p, \"%s\", \"%s\", \"%s\"}, %s, %s)", init.engine, init.filename, init.name, init.label, format, bool2str(use16Outs));

#ifdef WANT_LINUXSAMPLER
    if (init.engine->getProccessMode() == ENGINE_PROCESS_MODE_CONTINUOUS_RACK && use16Outs)
    {
        init.engine->setLastError("Carla's rack mode can only work with Stereo modules, please choose the 2-channel only sample-library version");
        return nullptr;
    }

    // -------------------------------------------------------------------
    // Check if file exists
    {
        QFileInfo file(init.filename);

        if (! file.exists())
        {
            init.engine->setLastError("Requested file does not exist");
            return nullptr;
        }

        if (! file.isFile())
        {
            init.engine->setLastError("Requested file is not valid");
            return nullptr;
        }

        if (! file.isReadable())
        {
            init.engine->setLastError("Requested file is not readable");
            return nullptr;
        }
    }

    LinuxSamplerPlugin* const plugin(new LinuxSamplerPlugin(init.engine, init.id, format, use16Outs));

    if (! plugin->init(init.filename, init.name, init.label))
    {
        delete plugin;
        return nullptr;
    }

    plugin->reload();

    return plugin;
#else
    init.engine->setLastError("linuxsampler support not available");
    return nullptr;

    // unused
    (void)format;
    (void)use16Outs;
#endif
}

CARLA_BACKEND_END_NAMESPACE