Carla/source/backend/engine/CarlaEngine.cpp

/*
 * Carla Plugin Host
 * 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:
 * - complete processRack(): carefully add to input, sorted events
 * - implement processPatchbay()
 * - implement oscSend_control_switch_plugins()
 * - proper find&load plugins
 * - something about the peaks?
 */

#include "CarlaEngineInternal.hpp"
#include "CarlaPlugin.hpp"

#include "CarlaBackendUtils.hpp"
#include "CarlaEngineUtils.hpp"
#include "CarlaMathUtils.hpp"
#include "CarlaStateUtils.hpp"
#include "CarlaMIDI.h"

#include "jackbridge/JackBridge.hpp"
#include "juce_core.h"

using juce::File;
using juce::MemoryOutputStream;
using juce::ScopedPointer;
using juce::String;
using juce::XmlDocument;
using juce::XmlElement;

CARLA_BACKEND_START_NAMESPACE

// -----------------------------------------------------------------------
// Carla Engine

CarlaEngine::CarlaEngine()
    : pData(new ProtectedData(this))
{
    carla_debug("CarlaEngine::CarlaEngine()");
}

CarlaEngine::~CarlaEngine()
{
    carla_debug("CarlaEngine::~CarlaEngine()");

    delete pData;
}

// -----------------------------------------------------------------------
// Static calls

uint CarlaEngine::getDriverCount()
{
    carla_debug("CarlaEngine::getDriverCount()");

    uint count = 0;

    if (jackbridge_is_ok())
        count += 1;

#ifndef BUILD_BRIDGE
    count += getRtAudioApiCount();
    count += getJuceApiCount();
#endif

    return count;
}

const char* CarlaEngine::getDriverName(const uint index2)
{
    carla_debug("CarlaEngine::getDriverName(%i)", index2);

    uint index(index2);

    if (jackbridge_is_ok() && index-- == 0)
        return "JACK";

#ifndef BUILD_BRIDGE
    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getRtAudioApiName(index);
        index -= count;
    }

    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getJuceApiName(index);
        //index -= count;
    }
#endif

    carla_stderr("CarlaEngine::getDriverName(%i) - invalid index", index2);
    return nullptr;
}

const char* const* CarlaEngine::getDriverDeviceNames(const uint index2)
{
    carla_debug("CarlaEngine::getDriverDeviceNames(%i)", index2);

    uint index(index2);

    if (jackbridge_is_ok() && index-- == 0)
    {
        static const char* ret[3] = { "Auto-Connect OFF", "Auto-Connect ON", nullptr };
        return ret;
    }

#ifndef BUILD_BRIDGE
    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getRtAudioApiDeviceNames(index);
        index -= count;
    }

    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getJuceApiDeviceNames(index);
        //index -= count;
    }
#endif

    carla_stderr("CarlaEngine::getDriverDeviceNames(%i) - invalid index", index2);
    return nullptr;
}

const EngineDriverDeviceInfo* CarlaEngine::getDriverDeviceInfo(const uint index2, const char* const deviceName)
{
    carla_debug("CarlaEngine::getDriverDeviceInfo(%i, \"%s\")", index2, deviceName);

    uint index(index2);

    if (jackbridge_is_ok() && index-- == 0)
    {
        static uint32_t bufSizes[11] = { 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 0 };
        static EngineDriverDeviceInfo devInfo;
        devInfo.hints       = ENGINE_DRIVER_DEVICE_VARIABLE_BUFFER_SIZE;
        devInfo.bufferSizes = bufSizes;
        devInfo.sampleRates = nullptr;
        return &devInfo;
    }

#ifndef BUILD_BRIDGE
    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getRtAudioDeviceInfo(index, deviceName);
        index -= count;
    }

    if (const uint count = getRtAudioApiCount())
    {
        if (index < count)
            return getJuceDeviceInfo(index, deviceName);
        //index -= count;
    }
#endif

    carla_stderr("CarlaEngine::getDriverDeviceNames(%i, \"%s\") - invalid index", index2, deviceName);
    return nullptr;
}

CarlaEngine* CarlaEngine::newDriverByName(const char* const driverName)
{
    CARLA_SAFE_ASSERT_RETURN(driverName != nullptr && driverName[0] != '\0', nullptr);
    carla_debug("CarlaEngine::newDriverByName(\"%s\")", driverName);

    if (std::strcmp(driverName, "JACK") == 0)
        return newJack();

#ifndef BUILD_BRIDGE
    // -------------------------------------------------------------------
    // common

    if (std::strncmp(driverName, "JACK ", 5) == 0)
        return newRtAudio(AUDIO_API_JACK);

    // -------------------------------------------------------------------
    // linux

    if (std::strcmp(driverName, "ALSA") == 0)
        //return newJuce(AUDIO_API_ALSA);
        return newRtAudio(AUDIO_API_ALSA);

    if (std::strcmp(driverName, "OSS") == 0)
        return newRtAudio(AUDIO_API_OSS);
    if (std::strcmp(driverName, "PulseAudio") == 0)
        return newRtAudio(AUDIO_API_PULSE);

    // -------------------------------------------------------------------
    // macos

    if (std::strcmp(driverName, "CoreAudio") == 0)
        return newJuce(AUDIO_API_CORE);

    // -------------------------------------------------------------------
    // windows

    if (std::strcmp(driverName, "ASIO") == 0)
        return newJuce(AUDIO_API_ASIO);

    if (std::strcmp(driverName, "DirectSound") == 0)
        return newJuce(AUDIO_API_DS);
#endif

    carla_stderr("CarlaEngine::newDriverByName(\"%s\") - invalid driver name", driverName);
    return nullptr;
}

// -----------------------------------------------------------------------
// Constant values

uint CarlaEngine::getMaxClientNameSize() const noexcept
{
    return STR_MAX/2;
}

uint CarlaEngine::getMaxPortNameSize() const noexcept
{
    return STR_MAX;
}

uint CarlaEngine::getCurrentPluginCount() const noexcept
{
    return pData->curPluginCount;
}

uint CarlaEngine::getMaxPluginNumber() const noexcept
{
    return pData->maxPluginNumber;
}

// -----------------------------------------------------------------------
// Virtual, per-engine type calls

bool CarlaEngine::init(const char* const clientName)
{
    carla_debug("CarlaEngine::init(\"%s\")", clientName);

    if (! pData->init(clientName))
        return false;

    callback(ENGINE_CALLBACK_ENGINE_STARTED, 0, pData->options.processMode, pData->options.transportMode, 0.0f, getCurrentDriverName());
    return true;
}

bool CarlaEngine::close()
{
    carla_debug("CarlaEngine::close()");

    if (pData->curPluginCount != 0)
    {
        pData->aboutToClose = true;
        removeAllPlugins();
    }

#ifndef BUILD_BRIDGE
    if (pData->osc.isControlRegistered())
        oscSend_control_exit();
#endif

    pData->close();

    callback(ENGINE_CALLBACK_ENGINE_STOPPED, 0, 0, 0, 0.0f, nullptr);
    return true;
}

void CarlaEngine::idle() noexcept
{
    CARLA_SAFE_ASSERT_RETURN(pData->nextAction.opcode == kEnginePostActionNull,);
    CARLA_SAFE_ASSERT_RETURN(pData->nextPluginId == pData->maxPluginNumber,);

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CarlaPlugin* const plugin(pData->plugins[i].plugin);

        if (plugin != nullptr && plugin->isEnabled())
        {
            try {
                plugin->idle();
            } CARLA_SAFE_EXCEPTION_CONTINUE("Plugin idle");
        }
    }

    pData->osc.idle();
}

CarlaEngineClient* CarlaEngine::addClient(CarlaPlugin* const)
{
    return new CarlaEngineClient(*this);
}

// -----------------------------------------------------------------------
// Plugin management

bool CarlaEngine::addPlugin(const BinaryType btype, const PluginType ptype, const char* const filename, const char* const name, const char* const label, const int64_t uniqueId, const void* const extra)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextPluginId <= pData->maxPluginNumber, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(btype != BINARY_NONE, "Invalid plugin binary mode");
    CARLA_SAFE_ASSERT_RETURN_ERR(ptype != PLUGIN_NONE, "Invalid plugin type");
    CARLA_SAFE_ASSERT_RETURN_ERR((filename != nullptr && filename[0] != '\0') || (label != nullptr && label[0] != '\0'), "Invalid plugin filename and label");
    carla_debug("CarlaEngine::addPlugin(%i:%s, %i:%s, \"%s\", \"%s\", \"%s\", " P_INT64 ", %p)", btype, BinaryType2Str(btype), ptype, PluginType2Str(ptype), filename, name, label, uniqueId, extra);

    uint id;

#ifndef BUILD_BRIDGE
    CarlaPlugin* oldPlugin = nullptr;

    if (pData->nextPluginId < pData->curPluginCount)
    {
        id = pData->nextPluginId;
        pData->nextPluginId = pData->maxPluginNumber;

        oldPlugin = pData->plugins[id].plugin;

        CARLA_SAFE_ASSERT_RETURN_ERR(oldPlugin != nullptr, "Invalid replace plugin Id");
    }
    else
#endif
    {
        id = pData->curPluginCount;

        if (id == pData->maxPluginNumber)
        {
            setLastError("Maximum number of plugins reached");
            return false;
        }

        CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins[id].plugin == nullptr, "Invalid engine internal data");
    }

    CarlaPlugin::Initializer initializer = {
        this,
        id,
        filename,
        name,
        label,
        uniqueId
    };

    CarlaPlugin* plugin = nullptr;

#ifndef BUILD_BRIDGE
    CarlaString bridgeBinary(pData->options.binaryDir);

    if (bridgeBinary.isNotEmpty())
    {
# ifndef CARLA_OS_WIN
        if (btype == BINARY_NATIVE)
        {
            bridgeBinary += OS_SEP_STR "carla-bridge-native";
        }
        else
# endif
        {
            switch (btype)
            {
            case BINARY_POSIX32:
                bridgeBinary += OS_SEP_STR "carla-bridge-posix32";
                break;
            case BINARY_POSIX64:
                bridgeBinary += OS_SEP_STR "carla-bridge-posix64";
                break;
            case BINARY_WIN32:
                bridgeBinary += OS_SEP_STR "carla-bridge-win32.exe";
                break;
            case BINARY_WIN64:
                bridgeBinary += OS_SEP_STR "carla-bridge-win64.exe";
                break;
            default:
                bridgeBinary.clear();
                break;
            }
        }

        if (! File(bridgeBinary.buffer()).existsAsFile())
            bridgeBinary.clear();
    }

    if (ptype != PLUGIN_INTERNAL && (btype != BINARY_NATIVE || (pData->options.preferPluginBridges && bridgeBinary.isNotEmpty())))
    {
        if (bridgeBinary.isNotEmpty())
        {
            plugin = CarlaPlugin::newBridge(initializer, btype, ptype, bridgeBinary);
        }
# ifdef CARLA_OS_LINUX
        else if (btype == BINARY_WIN32)
        {
            // fallback to dssi-vst
            File file(filename);

            CarlaString label2(file.getFullPathName().toRawUTF8());
            label2.replace(' ', '*');

            CarlaPlugin::Initializer init2 = {
                this,
                id,
                "/usr/lib/dssi/dssi-vst.so",
                name,
                label2,
                uniqueId
            };

            char* const oldVstPath(getenv("VST_PATH"));
            carla_setenv("VST_PATH", file.getParentDirectory().getFullPathName().toRawUTF8());

            plugin = CarlaPlugin::newDSSI(init2);

            if (oldVstPath != nullptr)
                carla_setenv("VST_PATH", oldVstPath);
        }
# endif
        else
        {
            setLastError("This Carla build cannot handle this binary");
            return false;
        }
    }
    else
#endif // ! BUILD_BRIDGE
    {
        bool use16Outs;
        setLastError("Invalid or unsupported plugin type");

        switch (ptype)
        {
        case PLUGIN_NONE:
            break;

        case PLUGIN_INTERNAL:
            /*if (std::strcmp(label, "FluidSynth") == 0)
            {
                use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
                plugin = CarlaPlugin::newFluidSynth(initializer, use16Outs);
            }
            else if (std::strcmp(label, "LinuxSampler (GIG)") == 0)
            {
                use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
                plugin = CarlaPlugin::newLinuxSampler(initializer, "GIG", use16Outs);
            }
            else if (std::strcmp(label, "LinuxSampler (SF2)") == 0)
            {
                use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
                plugin = CarlaPlugin::newLinuxSampler(initializer, "SF2", use16Outs);
            }
            else if (std::strcmp(label, "LinuxSampler (SFZ)") == 0)
            {
                use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
                plugin = CarlaPlugin::newLinuxSampler(initializer, "SFZ", use16Outs);
            }*/
            plugin = CarlaPlugin::newNative(initializer);
            break;

        case PLUGIN_LADSPA:
            plugin = CarlaPlugin::newLADSPA(initializer, (const LADSPA_RDF_Descriptor*)extra);
            break;

        case PLUGIN_DSSI:
            plugin = CarlaPlugin::newDSSI(initializer);
            break;

        case PLUGIN_LV2:
            plugin = CarlaPlugin::newLV2(initializer);
            break;

        case PLUGIN_VST:
            plugin = CarlaPlugin::newVST(initializer);
            break;

        case PLUGIN_VST3:
            plugin = CarlaPlugin::newVST3(initializer);
            break;

        case PLUGIN_AU:
            plugin = CarlaPlugin::newAU(initializer);
            break;

        case PLUGIN_GIG:
            use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
            plugin = CarlaPlugin::newFileGIG(initializer, use16Outs);
            break;

        case PLUGIN_SF2:
            use16Outs = (extra != nullptr && std::strcmp((const char*)extra, "true") == 0);
            plugin = CarlaPlugin::newFileSF2(initializer, use16Outs);
            break;

        case PLUGIN_SFZ:
            plugin = CarlaPlugin::newFileSFZ(initializer);
            break;
        }
    }

    if (plugin == nullptr)
        return false;

    plugin->registerToOscClient();

    EnginePluginData& pluginData(pData->plugins[id]);
    pluginData.plugin      = plugin;
    pluginData.insPeak[0]  = 0.0f;
    pluginData.insPeak[1]  = 0.0f;
    pluginData.outsPeak[0] = 0.0f;
    pluginData.outsPeak[1] = 0.0f;

#ifndef BUILD_BRIDGE
    if (oldPlugin != nullptr)
    {
        // the engine thread might be reading from the old plugin
        pData->thread.stopThread(500);
        pData->thread.startThread();

        const bool  wasActive = oldPlugin->getInternalParameterValue(PARAMETER_ACTIVE) >= 0.5f;
        const float oldDryWet = oldPlugin->getInternalParameterValue(PARAMETER_DRYWET);
        const float oldVolume = oldPlugin->getInternalParameterValue(PARAMETER_VOLUME);

        delete oldPlugin;

        if (plugin->getHints() & PLUGIN_CAN_DRYWET)
            plugin->setDryWet(oldDryWet, true, true);

        if (plugin->getHints() & PLUGIN_CAN_VOLUME)
            plugin->setVolume(oldVolume, true, true);

        if (wasActive)
            plugin->setActive(true, true, true);

        callback(ENGINE_CALLBACK_RELOAD_ALL, id, 0, 0, 0.0f, nullptr);
    }
    else
#endif
    {
        ++pData->curPluginCount;
        callback(ENGINE_CALLBACK_PLUGIN_ADDED, id, 0, 0, 0.0f, plugin->getName());
    }

    return true;
}

bool CarlaEngine::addPlugin(const PluginType ptype, const char* const filename, const char* const name, const char* const label, const int64_t uniqueId, const void* const extra)
{
    return addPlugin(BINARY_NATIVE, ptype, filename, name, label, uniqueId, extra);
}

bool CarlaEngine::removePlugin(const uint id)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->curPluginCount != 0, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");
    carla_debug("CarlaEngine::removePlugin(%i)", id);

    CarlaPlugin* const plugin(pData->plugins[id].plugin);

    CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to remove");
    CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");

    pData->thread.stopThread(500);

#ifndef BUILD_BRIDGE
    const bool lockWait(isRunning() && pData->options.processMode != ENGINE_PROCESS_MODE_MULTIPLE_CLIENTS);
    const ScopedActionLock sal(pData, kEnginePostActionRemovePlugin, id, 0, lockWait);

    if (isOscControlRegistered())
        oscSend_control_remove_plugin(id);
#else
    pData->plugins[0].plugin = nullptr;
#endif

    delete plugin;

    if (isRunning() && ! pData->aboutToClose)
        pData->thread.startThread();

    callback(ENGINE_CALLBACK_PLUGIN_REMOVED, id, 0, 0, 0.0f, nullptr);
    return true;
}

bool CarlaEngine::removeAllPlugins()
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextPluginId == pData->maxPluginNumber, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    carla_debug("CarlaEngine::removeAllPlugins()");

    if (pData->curPluginCount == 0)
        return true;

    pData->thread.stopThread(500);

    const bool lockWait(isRunning());
    const ScopedActionLock sal(pData, kEnginePostActionZeroCount, 0, 0, lockWait);

    callback(ENGINE_CALLBACK_IDLE, 0, 0, 0, 0.0f, nullptr);

    for (uint i=0; i < pData->maxPluginNumber; ++i)
    {
        EnginePluginData& pluginData(pData->plugins[i]);

        if (pluginData.plugin != nullptr)
        {
            delete pluginData.plugin;
            pluginData.plugin = nullptr;
        }

        pluginData.insPeak[0]  = 0.0f;
        pluginData.insPeak[1]  = 0.0f;
        pluginData.outsPeak[0] = 0.0f;
        pluginData.outsPeak[1] = 0.0f;

        callback(ENGINE_CALLBACK_IDLE, 0, 0, 0, 0.0f, nullptr);
    }

    if (isRunning() && ! pData->aboutToClose)
        pData->thread.startThread();

    return true;
}

const char* CarlaEngine::renamePlugin(const uint id, const char* const newName)
{
    CARLA_SAFE_ASSERT_RETURN_ERRN(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->curPluginCount != 0, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(id < pData->curPluginCount, "Invalid plugin Id");
    CARLA_SAFE_ASSERT_RETURN_ERRN(newName != nullptr && newName[0] != '\0', "Invalid plugin name");
    carla_debug("CarlaEngine::renamePlugin(%i, \"%s\")", id, newName);

    CarlaPlugin* const plugin(pData->plugins[id].plugin);

    CARLA_SAFE_ASSERT_RETURN_ERRN(plugin != nullptr, "Could not find plugin to rename");
    CARLA_SAFE_ASSERT_RETURN_ERRN(plugin->getId() == id, "Invalid engine internal data");

    if (const char* const name = getUniquePluginName(newName))
    {
        plugin->setName(name);
        return name;
    }

    setLastError("Unable to get new unique plugin name");
    return nullptr;
}

bool CarlaEngine::clonePlugin(const uint id)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->curPluginCount != 0, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");
    carla_debug("CarlaEngine::clonePlugin(%i)", id);

    CarlaPlugin* const plugin(pData->plugins[id].plugin);

    CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to clone");
    CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");

    char label[STR_MAX+1];
    carla_zeroChar(label, STR_MAX+1);
    plugin->getLabel(label);

    const uint pluginCountBefore(pData->curPluginCount);

    if (! addPlugin(plugin->getBinaryType(), plugin->getType(), plugin->getFilename(), plugin->getName(), label, plugin->getUniqueId(), plugin->getExtraStuff()))
        return false;

    CARLA_SAFE_ASSERT_RETURN_ERR(pluginCountBefore+1 == pData->curPluginCount, "No new plugin found");

    if (CarlaPlugin* const newPlugin = pData->plugins[pluginCountBefore].plugin)
        newPlugin->loadStateSave(plugin->getStateSave());

    return true;
}

bool CarlaEngine::replacePlugin(const uint id)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->curPluginCount != 0, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    carla_debug("CarlaEngine::replacePlugin(%i)", id);

    // might use this to reset
    if (id == pData->curPluginCount || id == pData->maxPluginNumber)
    {
        pData->nextPluginId = pData->maxPluginNumber;
        return true;
    }

    CARLA_SAFE_ASSERT_RETURN_ERR(id < pData->curPluginCount, "Invalid plugin Id");

    CarlaPlugin* const plugin(pData->plugins[id].plugin);

    CARLA_SAFE_ASSERT_RETURN_ERR(plugin != nullptr, "Could not find plugin to replace");
    CARLA_SAFE_ASSERT_RETURN_ERR(plugin->getId() == id, "Invalid engine internal data");

    pData->nextPluginId = id;

    return true;
}

bool CarlaEngine::switchPlugins(const uint idA, const uint idB)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->curPluginCount >= 2, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(idA != idB, "Invalid operation, cannot switch plugin with itself");
    CARLA_SAFE_ASSERT_RETURN_ERR(idA < pData->curPluginCount, "Invalid plugin Id");
    CARLA_SAFE_ASSERT_RETURN_ERR(idB < pData->curPluginCount, "Invalid plugin Id");
    carla_debug("CarlaEngine::switchPlugins(%i)", idA, idB);

    CarlaPlugin* const pluginA(pData->plugins[idA].plugin);
    CarlaPlugin* const pluginB(pData->plugins[idB].plugin);

    CARLA_SAFE_ASSERT_RETURN_ERR(pluginA != nullptr, "Could not find plugin to switch");
    CARLA_SAFE_ASSERT_RETURN_ERR(pluginA != nullptr, "Could not find plugin to switch");
    CARLA_SAFE_ASSERT_RETURN_ERR(pluginA->getId() == idA, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERR(pluginB->getId() == idB, "Invalid engine internal data");

    pData->thread.stopThread(500);

#ifndef BUILD_BRIDGE
    const bool lockWait(isRunning() && pData->options.processMode != ENGINE_PROCESS_MODE_MULTIPLE_CLIENTS);
    const ScopedActionLock sal(pData, kEnginePostActionSwitchPlugins, idA, idB, lockWait);

    // TODO
    //if (isOscControlRegistered())
    //    oscSend_control_switch_plugins(idA, idB);
#else
    pData->plugins[0].plugin = nullptr;
#endif

    if (isRunning() && ! pData->aboutToClose)
        pData->thread.startThread();

    return true;
}

CarlaPlugin* CarlaEngine::getPlugin(const uint id) const
{
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->plugins != nullptr, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->curPluginCount != 0, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(pData->nextAction.opcode == kEnginePostActionNull, "Invalid engine internal data");
    CARLA_SAFE_ASSERT_RETURN_ERRN(id < pData->curPluginCount, "Invalid plugin Id");

    return pData->plugins[id].plugin;
}

CarlaPlugin* CarlaEngine::getPluginUnchecked(const uint id) const noexcept
{
    return pData->plugins[id].plugin;
}

const char* CarlaEngine::getUniquePluginName(const char* const name) const
{
    CARLA_SAFE_ASSERT_RETURN(pData->nextAction.opcode == kEnginePostActionNull, nullptr);
    CARLA_SAFE_ASSERT_RETURN(name != nullptr && name[0] != '\0', nullptr);
    carla_debug("CarlaEngine::getUniquePluginName(\"%s\")", name);

    CarlaString sname;
    sname = name;

    if (sname.isEmpty())
    {
        sname = "(No name)";
        return sname.dup();
    }

    const size_t maxNameSize(carla_min<uint>(getMaxClientNameSize(), 0xff, 6) - 6); // 6 = strlen(" (10)") + 1

    if (maxNameSize == 0 || ! isRunning())
        return sname.dup();

    sname.truncate(maxNameSize);
    sname.replace(':', '.'); // ':' is used in JACK1 to split client/port names

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CARLA_SAFE_ASSERT_BREAK(pData->plugins[i].plugin != nullptr);

        // Check if unique name doesn't exist
        if (const char* const pluginName = pData->plugins[i].plugin->getName())
        {
            if (sname != pluginName)
                continue;
        }

        // Check if string has already been modified
        {
            const size_t len(sname.length());

            // 1 digit, ex: " (2)"
            if (sname[len-4] == ' ' && sname[len-3] == '(' && sname.isDigit(len-2) && sname[len-1] == ')')
            {
                int number = sname[len-2] - '0';

                if (number == 9)
                {
                    // next number is 10, 2 digits
                    sname.truncate(len-4);
                    sname += " (10)";
                    //sname.replace(" (9)", " (10)");
                }
                else
                    sname[len-2] = char('0' + number + 1);

                continue;
            }

            // 2 digits, ex: " (11)"
            if (sname[len-5] == ' ' && sname[len-4] == '(' && sname.isDigit(len-3) && sname.isDigit(len-2) && sname[len-1] == ')')
            {
                char n2 = sname[len-2];
                char n3 = sname[len-3];

                if (n2 == '9')
                {
                    n2 = '0';
                    n3 = static_cast<char>(n3 + 1);
                }
                else
                    n2 = static_cast<char>(n2 + 1);

                sname[len-2] = n2;
                sname[len-3] = n3;

                continue;
            }
        }

        // Modify string if not
        sname += " (2)";
    }

    return sname.dup();
}

// -----------------------------------------------------------------------
// Project management

bool CarlaEngine::loadFile(const char* const filename)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(filename != nullptr && filename[0] != '\0', "Invalid filename");
    carla_debug("CarlaEngine::loadFile(\"%s\")", filename);

    File file(filename);
    CARLA_SAFE_ASSERT_RETURN_ERR(file.existsAsFile(), "Requested file does not exist or is not a readable file");

    CarlaString baseName(file.getFileName().toRawUTF8());
    CarlaString extension(file.getFileExtension().toRawUTF8());
    extension.toLower();

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

    if (extension == "carxp" || extension == "carxs")
        return loadProject(filename);

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

    if (extension == "gig")
        return addPlugin(PLUGIN_GIG, filename, baseName, baseName, 0, nullptr);

    if (extension == "sf2")
        return addPlugin(PLUGIN_SF2, filename, baseName, baseName, 0, nullptr);

    if (extension == "sfz")
        return addPlugin(PLUGIN_SFZ, filename, baseName, baseName, 0, nullptr);

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

    if (extension == "aiff" || extension == "flac" || extension == "oga" || extension == "ogg" || extension == "w64" || extension == "wav")
    {
#ifdef WANT_AUDIOFILE
        if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "audiofile", 0, nullptr))
        {
            if (CarlaPlugin* const plugin = getPlugin(pData->curPluginCount-1))
                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "file", filename, true);
            return true;
        }
        return false;
#else
        setLastError("This Carla build does not have Audio file support");
        return false;
#endif
    }

    if (extension == "3g2" || extension == "3gp" || extension == "aac" || extension == "ac3" || extension == "amr" || extension == "ape" ||
            extension == "mp2" || extension == "mp3" || extension == "mpc" || extension == "wma")
    {
#ifdef WANT_AUDIOFILE
# ifdef HAVE_FFMPEG
        if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "audiofile", 0, nullptr))
        {
            if (CarlaPlugin* const plugin = getPlugin(pData->curPluginCount-1))
                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "file", filename, true);
            return true;
        }
        return false;
# else
        setLastError("This Carla build has Audio file support, but not libav/ffmpeg");
        return false;
# endif
#else
        setLastError("This Carla build does not have Audio file support");
        return false;
#endif
    }

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

    if (extension == "mid" || extension == "midi")
    {
#ifdef WANT_MIDIFILE
        if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "midifile", 0, nullptr))
        {
            if (CarlaPlugin* const plugin = getPlugin(pData->curPluginCount-1))
                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, "file", filename, true);
            return true;
        }
        return false;
#else
        setLastError("This Carla build does not have MIDI file support");
        return false;
#endif
    }

    // -------------------------------------------------------------------
    // ZynAddSubFX

    if (extension == "xmz" || extension == "xiz")
    {
#ifdef WANT_ZYNADDSUBFX
        if (addPlugin(PLUGIN_INTERNAL, nullptr, baseName, "zynaddsubfx", 0, nullptr))
        {
            if (CarlaPlugin* const plugin = getPlugin(pData->curPluginCount-1))
                plugin->setCustomData(CUSTOM_DATA_TYPE_STRING, (extension == "xmz") ? "CarlaAlternateFile1" : "CarlaAlternateFile2", filename, true);
            return true;
        }
        return false;
#else
        setLastError("This Carla build does not have ZynAddSubFX support");
        return false;
#endif
    }

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

    setLastError("Unknown file extension");
    return false;
}

bool CarlaEngine::loadProject(const char* const filename)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(! pData->isIdling, "An operation is still being processed, please wait for it to finish");
    CARLA_SAFE_ASSERT_RETURN_ERR(filename != nullptr && filename[0] != '\0', "Invalid filename");
    carla_debug("CarlaEngine::loadProject(\"%s\")", filename);

    File file(filename);
    CARLA_SAFE_ASSERT_RETURN_ERR(file.existsAsFile(), "Requested file does not exist or is not a readable file");

    XmlDocument xml(file);
    ScopedPointer<XmlElement> xmlElement(xml.getDocumentElement(true));
    CARLA_SAFE_ASSERT_RETURN_ERR(xmlElement != nullptr, "Failed to parse project file");

    const String& xmlType(xmlElement->getTagName());
    const bool isPreset(xmlType.equalsIgnoreCase("carla-preset"));

    if (! (xmlType.equalsIgnoreCase("carla-project") || isPreset))
    {
        setLastError("Not a valid Carla project or preset file");
        return false;
    }

    // completely load file
    xmlElement = xml.getDocumentElement(false);
    CARLA_SAFE_ASSERT_RETURN_ERR(xmlElement != nullptr, "Failed to completely parse project file");

    // handle plugins first
    for (XmlElement* elem = xmlElement->getFirstChildElement(); elem != nullptr; elem = elem->getNextElement())
    {
        const String& tagName(elem->getTagName());

        if (isPreset || tagName.equalsIgnoreCase("plugin"))
        {
            StateSave stateSave;
            stateSave.fillFromXmlElement(isPreset ? xmlElement.get() : elem);

            callback(ENGINE_CALLBACK_IDLE, 0, 0, 0, 0.0f, nullptr);

            CARLA_SAFE_ASSERT_CONTINUE(stateSave.type != nullptr);

            const void* extraStuff = nullptr;

            // check if using GIG, SF2 or SFZ 16outs
            static const char kUse16OutsSuffix[] = " (16 outs)";

            const PluginType ptype(getPluginTypeFromString(stateSave.type));

            if (CarlaString(stateSave.label).endsWith(kUse16OutsSuffix))
            {
                if (ptype == PLUGIN_GIG || ptype == PLUGIN_SF2)
                    extraStuff = "true";
            }

            // TODO - proper find&load plugins

            if (addPlugin(ptype, stateSave.binary, stateSave.name, stateSave.label, stateSave.uniqueId, extraStuff))
            {
                if (CarlaPlugin* const plugin = getPlugin(pData->curPluginCount-1))
                    plugin->loadStateSave(stateSave);
            }
            else
                carla_stderr2("Failed to load a plugin, error was:%s\n", getLastError());
        }

        if (isPreset)
            return true;
    }

#ifndef BUILD_BRIDGE
    callback(ENGINE_CALLBACK_IDLE, 0, 0, 0, 0.0f, nullptr);

    // if we're running inside some session-manager, let them handle the connections
    if (pData->options.processMode != ENGINE_PROCESS_MODE_PATCHBAY)
    {
        if (std::getenv("CARLA_DONT_MANAGE_CONNECTIONS") != nullptr || std::getenv("LADISH_APP_NAME") != nullptr || std::getenv("NSM_URL") != nullptr)
            return true;
    }

    // now handle connections
    for (XmlElement* elem = xmlElement->getFirstChildElement(); elem != nullptr; elem = elem->getNextElement())
    {
        const String& tagName(elem->getTagName());

        if (tagName.equalsIgnoreCase("patchbay"))
        {
            CarlaString sourcePort, targetPort;

            for (XmlElement* patchElem = elem->getFirstChildElement(); patchElem != nullptr; patchElem = patchElem->getNextElement())
            {
                const String& patchTag(patchElem->getTagName());

                sourcePort.clear();
                targetPort.clear();

                if (! patchTag.equalsIgnoreCase("connection"))
                    continue;

                for (XmlElement* connElem = patchElem->getFirstChildElement(); connElem != nullptr; connElem = connElem->getNextElement())
                {
                    const String& tag(connElem->getTagName());
                    const String  text(connElem->getAllSubText().trim());

                    if (tag.equalsIgnoreCase("source"))
                        sourcePort = text.toRawUTF8();
                    else if (tag.equalsIgnoreCase("target"))
                        targetPort = text.toRawUTF8();
                }

                if (sourcePort.isNotEmpty() && targetPort.isNotEmpty())
                    restorePatchbayConnection(sourcePort, targetPort);
            }
            break;
        }
    }
#endif

    return true;
}

bool CarlaEngine::saveProject(const char* const filename)
{
    CARLA_SAFE_ASSERT_RETURN_ERR(filename != nullptr && filename[0] != '\0', "Invalid filename");
    carla_debug("CarlaEngine::saveProject(\"%s\")", filename);

    MemoryOutputStream out;
    out << "<?xml version='1.0' encoding='UTF-8'?>\n";
    out << "<!DOCTYPE CARLA-PROJECT>\n";
    out << "<CARLA-PROJECT VERSION='2.0'>\n";

    bool firstPlugin = true;
    char strBuf[STR_MAX+1];

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CarlaPlugin* const plugin(pData->plugins[i].plugin);

        if (plugin != nullptr && plugin->isEnabled())
        {
            if (! firstPlugin)
                out << "\n";

            strBuf[0] = '\0';

            plugin->getRealName(strBuf);

            //if (strBuf[0] != '\0')
            //    out << QString(" <!-- %1 -->\n").arg(xmlSafeString(strBuf, true));

            out << " <Plugin>\n";
            out << plugin->getStateSave().toString();
            out << " </Plugin>\n";

            firstPlugin = false;
        }
    }

#ifndef BUILD_BRIDGE
    // if we're running inside some session-manager, let them handle the connections
    if (pData->options.processMode != ENGINE_PROCESS_MODE_PATCHBAY)
    {
        if (std::getenv("CARLA_DONT_MANAGE_CONNECTIONS") != nullptr || std::getenv("LADISH_APP_NAME") != nullptr || std::getenv("NSM_URL") != nullptr)
            return true;
    }

    if (const char* const* patchbayConns = getPatchbayConnections())
    {
        if (! firstPlugin)
            out << "\n";

        out << " <Patchbay>\n";

        for (int i=0; patchbayConns[i] != nullptr && patchbayConns[i+1] != nullptr; ++i, ++i )
        {
            const char* const connSource(patchbayConns[i]);
            const char* const connTarget(patchbayConns[i+1]);

            CARLA_SAFE_ASSERT_CONTINUE(connSource != nullptr && connSource[0] != '\0');
            CARLA_SAFE_ASSERT_CONTINUE(connTarget != nullptr && connTarget[0] != '\0');

            out << "  <Connection>\n";
            out << "   <Source>" << connSource << "</Source>\n";
            out << "   <Target>" << connTarget << "</Target>\n";
            out << "  </Connection>\n";

            delete[] connSource;
            delete[] connTarget;
        }

        out << " </Patchbay>\n";
    }
#endif

    out << "</CARLA-PROJECT>\n";

    File file(filename);

    if (file.replaceWithData(out.getData(), out.getDataSize()))
        return true;

    setLastError("Failed to write file");
    return false;
}

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

uint CarlaEngine::getHints() const noexcept
{
    return pData->hints;
}

uint32_t CarlaEngine::getBufferSize() const noexcept
{
    return pData->bufferSize;
}

double CarlaEngine::getSampleRate() const noexcept
{
    return pData->sampleRate;
}

const char* CarlaEngine::getName() const noexcept
{
    return pData->name;
}

EngineProcessMode CarlaEngine::getProccessMode() const noexcept
{
    return pData->options.processMode;
}

const EngineOptions& CarlaEngine::getOptions() const noexcept
{
    return pData->options;
}

const EngineTimeInfo& CarlaEngine::getTimeInfo() const noexcept
{
    return pData->timeInfo;
}

// -----------------------------------------------------------------------
// Information (peaks)

float CarlaEngine::getInputPeak(const uint pluginId, const bool isLeft) const noexcept
{
    CARLA_SAFE_ASSERT_RETURN(pluginId < pData->curPluginCount, 0.0f);

    return pData->plugins[pluginId].insPeak[isLeft ? 0 : 1];
}

float CarlaEngine::getOutputPeak(const uint pluginId, const bool isLeft) const noexcept
{
    CARLA_SAFE_ASSERT_RETURN(pluginId < pData->curPluginCount, 0.0f);

    return pData->plugins[pluginId].outsPeak[isLeft ? 0 : 1];
}

// -----------------------------------------------------------------------
// Callback

void CarlaEngine::callback(const EngineCallbackOpcode action, const uint pluginId, const int value1, const int value2, const float value3, const char* const valueStr) noexcept
{
    carla_debug("CarlaEngine::callback(%i:%s, %i, %i, %i, %f, \"%s\")", action, EngineCallbackOpcode2Str(action), pluginId, value1, value2, value3, valueStr);

    if (pData->isIdling && action != ENGINE_CALLBACK_PATCHBAY_CLIENT_DATA_CHANGED)
        carla_stdout("callback while idling (%i:%s, %i, %i, %i, %f, \"%s\")", action, EngineCallbackOpcode2Str(action), pluginId, value1, value2, value3, valueStr);

    if (action == ENGINE_CALLBACK_IDLE)
        pData->isIdling = true;

    if (pData->callback != nullptr)
    {
        try {
            pData->callback(pData->callbackPtr, action, pluginId, value1, value2, value3, valueStr);
        } catch(...) {}
    }

    if (action == ENGINE_CALLBACK_IDLE)
        pData->isIdling = false;
}

void CarlaEngine::setCallback(const EngineCallbackFunc func, void* const ptr) noexcept
{
    carla_debug("CarlaEngine::setCallback(%p, %p)", func, ptr);

    pData->callback    = func;
    pData->callbackPtr = ptr;
}

// -----------------------------------------------------------------------
// File Callback

const char* CarlaEngine::runFileCallback(const FileCallbackOpcode action, const bool isDir, const char* const title, const char* const filter) noexcept
{
    CARLA_SAFE_ASSERT_RETURN(title != nullptr && title[0] != '\0', nullptr);
    CARLA_SAFE_ASSERT_RETURN(filter != nullptr, nullptr);
    carla_debug("CarlaEngine::runFileCallback(%i:%s, %s, \"%s\", \"%s\")", action, FileCallbackOpcode2Str(action), bool2str(isDir), title, filter);

    const char* ret = nullptr;

    if (pData->fileCallback != nullptr)
    {
        try {
            ret = pData->fileCallback(pData->fileCallbackPtr, action, isDir, title, filter);
        } catch(...) {}
    }

    return ret;
}

void CarlaEngine::setFileCallback(const FileCallbackFunc func, void* const ptr) noexcept
{
    carla_debug("CarlaEngine::setFileCallback(%p, %p)", func, ptr);

    pData->fileCallback    = func;
    pData->fileCallbackPtr = ptr;
}

// -----------------------------------------------------------------------
// Transport

void CarlaEngine::transportPlay() noexcept
{
    pData->time.playing = true;
}

void CarlaEngine::transportPause() noexcept
{
    pData->time.playing = false;
}

void CarlaEngine::transportRelocate(const uint64_t frame) noexcept
{
    pData->time.frame = frame;
}

// -----------------------------------------------------------------------
// Error handling

const char* CarlaEngine::getLastError() const noexcept
{
    return pData->lastError;
}

void CarlaEngine::setLastError(const char* const error) const noexcept
{
    pData->lastError = error;
}

void CarlaEngine::setAboutToClose() noexcept
{
    carla_debug("CarlaEngine::setAboutToClose()");

    pData->aboutToClose = true;
}

// -----------------------------------------------------------------------
// Global options

void CarlaEngine::setOption(const EngineOption option, const int value, const char* const valueStr)
{
    carla_debug("CarlaEngine::setOption(%i:%s, %i, \"%s\")", option, EngineOption2Str(option), value, valueStr);

    if (isRunning() && (option == ENGINE_OPTION_PROCESS_MODE || option == ENGINE_OPTION_AUDIO_NUM_PERIODS || option == ENGINE_OPTION_AUDIO_DEVICE))
        return carla_stderr("CarlaEngine::setOption(%i:%s, %i, \"%s\") - Cannot set this option while engine is running!", option, EngineOption2Str(option), value, valueStr);

    switch (option)
    {
    case ENGINE_OPTION_DEBUG:
    case ENGINE_OPTION_NSM_INIT:
        break;

    case ENGINE_OPTION_PROCESS_MODE:
        CARLA_SAFE_ASSERT_RETURN(value >= ENGINE_PROCESS_MODE_SINGLE_CLIENT && value <= ENGINE_PROCESS_MODE_BRIDGE,);
        pData->options.processMode = static_cast<EngineProcessMode>(value);
        break;

    case ENGINE_OPTION_TRANSPORT_MODE:
        CARLA_SAFE_ASSERT_RETURN(value >= ENGINE_TRANSPORT_MODE_INTERNAL && value <= ENGINE_TRANSPORT_MODE_BRIDGE,);
        pData->options.transportMode = static_cast<EngineTransportMode>(value);
        break;

    case ENGINE_OPTION_FORCE_STEREO:
        CARLA_SAFE_ASSERT_RETURN(value == 0 || value == 1,);
        pData->options.forceStereo = (value != 0);
        break;

    case ENGINE_OPTION_PREFER_PLUGIN_BRIDGES:
        CARLA_SAFE_ASSERT_RETURN(value == 0 || value == 1,);
        pData->options.preferPluginBridges = (value != 0);
        break;

    case ENGINE_OPTION_PREFER_UI_BRIDGES:
        CARLA_SAFE_ASSERT_RETURN(value == 0 || value == 1,);
        pData->options.preferUiBridges = (value != 0);
        break;

    case ENGINE_OPTION_UIS_ALWAYS_ON_TOP:
        CARLA_SAFE_ASSERT_RETURN(value == 0 || value == 1,);
        pData->options.uisAlwaysOnTop = (value != 0);
        break;

    case ENGINE_OPTION_MAX_PARAMETERS:
        CARLA_SAFE_ASSERT_RETURN(value >= 0,);
        pData->options.maxParameters = static_cast<uint>(value);
        break;

    case ENGINE_OPTION_UI_BRIDGES_TIMEOUT:
        CARLA_SAFE_ASSERT_RETURN(value >= 0,);
        pData->options.uiBridgesTimeout = static_cast<uint>(value);
        break;

    case ENGINE_OPTION_AUDIO_NUM_PERIODS:
        CARLA_SAFE_ASSERT_RETURN(value >= 2 && value <= 3,);
        pData->options.audioNumPeriods = static_cast<uint>(value);
        break;

    case ENGINE_OPTION_AUDIO_BUFFER_SIZE:
        CARLA_SAFE_ASSERT_RETURN(value >= 8,);
        pData->options.audioBufferSize = static_cast<uint>(value);
        break;

    case ENGINE_OPTION_AUDIO_SAMPLE_RATE:
        CARLA_SAFE_ASSERT_RETURN(value >= 22050,);
        pData->options.audioSampleRate = static_cast<uint>(value);
        break;

    case ENGINE_OPTION_AUDIO_DEVICE:
        CARLA_SAFE_ASSERT_RETURN(valueStr != nullptr,);

        if (pData->options.audioDevice != nullptr)
            delete[] pData->options.audioDevice;

        pData->options.audioDevice = carla_strdup(valueStr);
        break;

    case ENGINE_OPTION_PATH_BINARIES:
        CARLA_SAFE_ASSERT_RETURN(valueStr != nullptr && valueStr[0] != '\0',);

        if (pData->options.binaryDir != nullptr)
            delete[] pData->options.binaryDir;

        pData->options.binaryDir = carla_strdup(valueStr);
        break;

    case ENGINE_OPTION_PATH_RESOURCES:
        CARLA_SAFE_ASSERT_RETURN(valueStr != nullptr && valueStr[0] != '\0',);

        if (pData->options.resourceDir != nullptr)
            delete[] pData->options.resourceDir;

        pData->options.resourceDir = carla_strdup(valueStr);
        break;

    case ENGINE_OPTION_FRONTEND_WIN_ID:
        CARLA_SAFE_ASSERT_RETURN(valueStr != nullptr && valueStr[0] != '\0',);
        const long long winId(std::strtoll(valueStr, nullptr, 16));
        CARLA_SAFE_ASSERT_RETURN(winId >= 0,);
        pData->options.frontendWinId = static_cast<uintptr_t>(winId);
        break;
    }
}

// -----------------------------------------------------------------------
// OSC Stuff

#ifdef BUILD_BRIDGE
bool CarlaEngine::isOscBridgeRegistered() const noexcept
{
    return (pData->oscData != nullptr);
}
#else
bool CarlaEngine::isOscControlRegistered() const noexcept
{
    return pData->osc.isControlRegistered();
}
#endif

void CarlaEngine::idleOsc() const noexcept
{
    pData->osc.idle();
}

const char* CarlaEngine::getOscServerPathTCP() const noexcept
{
    return pData->osc.getServerPathTCP();
}

const char* CarlaEngine::getOscServerPathUDP() const noexcept
{
    return pData->osc.getServerPathUDP();
}

#ifdef BUILD_BRIDGE
void CarlaEngine::setOscBridgeData(const CarlaOscData* const oscData) const noexcept
{
    pData->oscData = oscData;
}
#endif

// -----------------------------------------------------------------------
// Helper functions

EngineEvent* CarlaEngine::getInternalEventBuffer(const bool isInput) const noexcept
{
    return isInput ? pData->events.in : pData->events.out;
}

void CarlaEngine::registerEnginePlugin(const uint id, CarlaPlugin* const plugin) noexcept
{
    CARLA_SAFE_ASSERT_RETURN(id == pData->curPluginCount,);
    carla_debug("CarlaEngine::registerEnginePlugin(%i, %p)", id, plugin);

    pData->plugins[id].plugin = plugin;
}

// -----------------------------------------------------------------------
// Internal stuff

void CarlaEngine::bufferSizeChanged(const uint32_t newBufferSize)
{
    carla_debug("CarlaEngine::bufferSizeChanged(%i)", newBufferSize);

#ifndef BUILD_BRIDGE
    pData->graph.setBufferSize(newBufferSize);
#endif

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CarlaPlugin* const plugin(pData->plugins[i].plugin);

        if (plugin != nullptr && plugin->isEnabled())
            plugin->bufferSizeChanged(newBufferSize);
    }

    callback(ENGINE_CALLBACK_BUFFER_SIZE_CHANGED, 0, static_cast<int>(newBufferSize), 0, 0.0f, nullptr);
}

void CarlaEngine::sampleRateChanged(const double newSampleRate)
{
    carla_debug("CarlaEngine::sampleRateChanged(%g)", newSampleRate);

#ifndef BUILD_BRIDGE
    pData->graph.setSampleRate(newSampleRate);
#endif

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CarlaPlugin* const plugin(pData->plugins[i].plugin);

        if (plugin != nullptr && plugin->isEnabled())
            plugin->sampleRateChanged(newSampleRate);
    }

    callback(ENGINE_CALLBACK_SAMPLE_RATE_CHANGED, 0, 0, 0, static_cast<float>(newSampleRate), nullptr);
}

void CarlaEngine::offlineModeChanged(const bool isOfflineNow)
{
    carla_debug("CarlaEngine::offlineModeChanged(%s)", bool2str(isOfflineNow));

#ifndef BUILD_BRIDGE
    pData->graph.setOffline(isOfflineNow);
#endif

    for (uint i=0; i < pData->curPluginCount; ++i)
    {
        CarlaPlugin* const plugin(pData->plugins[i].plugin);

        if (plugin != nullptr && plugin->isEnabled())
            plugin->offlineModeChanged(isOfflineNow);
    }
}

void CarlaEngine::runPendingRtEvents() noexcept
{
    pData->doNextPluginAction(true);

    if (pData->time.playing)
        pData->time.frame += pData->bufferSize;

    if (pData->options.transportMode == ENGINE_TRANSPORT_MODE_INTERNAL)
    {
        pData->timeInfo.playing = pData->time.playing;
        pData->timeInfo.frame   = pData->time.frame;
    }
}

void CarlaEngine::setPluginPeaks(const uint pluginId, float const inPeaks[2], float const outPeaks[2]) noexcept
{
    EnginePluginData& pluginData(pData->plugins[pluginId]);

    pluginData.insPeak[0]  = inPeaks[0];
    pluginData.insPeak[1]  = inPeaks[1];
    pluginData.outsPeak[0] = outPeaks[0];
    pluginData.outsPeak[1] = outPeaks[1];
}

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

CARLA_BACKEND_END_NAMESPACE