LADSPAPluginFactory.cpp

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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    
    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 (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

/*
   This is a modified version of a source file from the 
   Rosegarden MIDI and audio sequencer and notation editor.
   This file copyright 2000-2006 Chris Cannam and Richard Bown.
*/

#include "LADSPAPluginFactory.h"
#include <iostream>

#include <QDir>
#include <QFile>
#include <QTextStream>

#include <cmath>

#include "LADSPAPluginInstance.h"
#include "PluginIdentifier.h"

#include "system/System.h"
#include "base/Preferences.h"
#include "base/Profiler.h"

//#define DEBUG_LADSPA_PLUGIN_FACTORY 1

#ifdef HAVE_LRDF
#include "lrdf.h"
#endif // HAVE_LRDF

using std::string;

LADSPAPluginFactory::LADSPAPluginFactory()
{
#ifdef HAVE_LRDF
    lrdf_init();
#endif
}
 
LADSPAPluginFactory::~LADSPAPluginFactory()
{
    unloadUnusedLibraries();

#ifdef HAVE_LRDF
    lrdf_cleanup();
#endif // HAVE_LRDF
}

const std::vector<QString> &
LADSPAPluginFactory::getPluginIdentifiers() const
{
    return m_identifiers;
}

QString
LADSPAPluginFactory::getPluginLibraryPath(QString identifier)
{
    return m_libraries[identifier];
}

void
LADSPAPluginFactory::enumeratePlugins(std::vector<QString> &list)
{
    Profiler profiler("LADSPAPluginFactory::enumeratePlugins");

    for (std::vector<QString>::iterator i = m_identifiers.begin();
         i != m_identifiers.end(); ++i) {

        const LADSPA_Descriptor *descriptor = getLADSPADescriptor(*i);

        if (!descriptor) {
            SVCERR << "WARNING: LADSPAPluginFactory::enumeratePlugins: couldn't get descriptor for identifier " << *i << endl;
            continue;
        }
        
        list.push_back(*i);
        list.push_back(descriptor->Name);
        list.push_back(QString("%1").arg(descriptor->UniqueID));
        list.push_back(descriptor->Label);
        list.push_back(descriptor->Maker);
        list.push_back(descriptor->Copyright);
        list.push_back("false"); // is synth
        list.push_back("false"); // is grouped

        if (m_taxonomy.find(*i) != m_taxonomy.end() && m_taxonomy[*i] != "") {
//                SVCERR << "LADSPAPluginFactory: cat for " << *i << " found in taxonomy as " << m_taxonomy[descriptor->UniqueID] << endl;
            list.push_back(m_taxonomy[*i]);
        } else {
            list.push_back("");
//                SVCERR << "LADSPAPluginFactory: cat for " << *i << " not found (despite having " << m_fallbackCategories.size() << " fallbacks)" << endl;
            
        }

        list.push_back(QString("%1").arg(descriptor->PortCount));

        for (int p = 0; p < (int)descriptor->PortCount; ++p) {

            int type = 0;
            if (LADSPA_IS_PORT_CONTROL(descriptor->PortDescriptors[p])) {
                type |= PortType::Control;
            } else {
                type |= PortType::Audio;
            }
            if (LADSPA_IS_PORT_INPUT(descriptor->PortDescriptors[p])) {
                type |= PortType::Input;
            } else {
                type |= PortType::Output;
            }

            list.push_back(QString("%1").arg(p));
            list.push_back(descriptor->PortNames[p]);
            list.push_back(QString("%1").arg(type));
            list.push_back(QString("%1").arg(getPortDisplayHint(descriptor, p)));
            list.push_back(QString("%1").arg(getPortMinimum(descriptor, p)));
            list.push_back(QString("%1").arg(getPortMaximum(descriptor, p)));
            list.push_back(QString("%1").arg(getPortDefault(descriptor, p)));
        }
    }

    unloadUnusedLibraries();
}
        
RealTimePluginDescriptor
LADSPAPluginFactory::getPluginDescriptor(QString identifier) const
{
    std::map<QString, RealTimePluginDescriptor>::const_iterator i =
        m_rtDescriptors.find(identifier);

    if (i != m_rtDescriptors.end()) {
        return i->second;
    } 

    return {};
}

float
LADSPAPluginFactory::getPortMinimum(const LADSPA_Descriptor *descriptor, int port)
{
    LADSPA_PortRangeHintDescriptor d =
        descriptor->PortRangeHints[port].HintDescriptor;

    float minimum = 0.f;
                
    if (LADSPA_IS_HINT_BOUNDED_BELOW(d)) {
        float lb = descriptor->PortRangeHints[port].LowerBound;
        minimum = lb;
    } else if (LADSPA_IS_HINT_BOUNDED_ABOVE(d)) {
        float ub = descriptor->PortRangeHints[port].UpperBound;
        minimum = std::min(0.f, ub - 1.f);
    }
    
    if (LADSPA_IS_HINT_SAMPLE_RATE(d)) {
        minimum = float(minimum * m_sampleRate);
    }

    if (LADSPA_IS_HINT_LOGARITHMIC(d)) {
        if (minimum == 0.f) minimum = 1.f;
    }

    return minimum;
}

float
LADSPAPluginFactory::getPortMaximum(const LADSPA_Descriptor *descriptor, int port)
{
    LADSPA_PortRangeHintDescriptor d =
        descriptor->PortRangeHints[port].HintDescriptor;

    float maximum = 1.f;
    
    if (LADSPA_IS_HINT_BOUNDED_ABOVE(d)) {
        float ub = descriptor->PortRangeHints[port].UpperBound;
        maximum = ub;
    } else {
        float lb = descriptor->PortRangeHints[port].LowerBound;
        maximum = lb + 1.f;
    }
    
    if (LADSPA_IS_HINT_SAMPLE_RATE(d)) {
        maximum = float(maximum * m_sampleRate);
    }

    return maximum;
}

float
LADSPAPluginFactory::getPortDefault(const LADSPA_Descriptor *descriptor, int port)
{
    float minimum = getPortMinimum(descriptor, port);
    float maximum = getPortMaximum(descriptor, port);
    float deft;

    if (m_portDefaults.find(descriptor->UniqueID) != 
        m_portDefaults.end()) {
        if (m_portDefaults[descriptor->UniqueID].find(port) !=
            m_portDefaults[descriptor->UniqueID].end()) {

            deft = m_portDefaults[descriptor->UniqueID][port];
            if (deft < minimum) deft = minimum;
            if (deft > maximum) deft = maximum;
            return deft;
        }
    }

    LADSPA_PortRangeHintDescriptor d =
        descriptor->PortRangeHints[port].HintDescriptor;

    bool logarithmic = LADSPA_IS_HINT_LOGARITHMIC(d);
    
    float logmin = 0, logmax = 0;
    if (logarithmic) {
        float thresh = powf(10, -10);
        if (minimum < thresh) logmin = -10;
        else logmin = log10f(minimum);
        if (maximum < thresh) logmax = -10;
        else logmax = log10f(maximum);
    }

//    SVDEBUG << "LADSPAPluginFactory::getPortDefault: hint = " << d << endl;

    if (!LADSPA_IS_HINT_HAS_DEFAULT(d)) {
        
        deft = minimum;
        
    } else if (LADSPA_IS_HINT_DEFAULT_MINIMUM(d)) {
        
        deft = minimum;
        
    } else if (LADSPA_IS_HINT_DEFAULT_LOW(d)) {
        
        if (logarithmic) {
            deft = powf(10, logmin * 0.75f + logmax * 0.25f);
        } else {
            deft = minimum * 0.75f + maximum * 0.25f;
        }
        
    } else if (LADSPA_IS_HINT_DEFAULT_MIDDLE(d)) {
        
        if (logarithmic) {
            deft = powf(10, logmin * 0.5f + logmax * 0.5f);
        } else {
            deft = minimum * 0.5f + maximum * 0.5f;
        }
        
    } else if (LADSPA_IS_HINT_DEFAULT_HIGH(d)) {
        
        if (logarithmic) {
            deft = powf(10, logmin * 0.25f + logmax * 0.75f);
        } else {
            deft = minimum * 0.25f + maximum * 0.75f;
        }
        
    } else if (LADSPA_IS_HINT_DEFAULT_MAXIMUM(d)) {
        
        deft = maximum;
        
    } else if (LADSPA_IS_HINT_DEFAULT_0(d)) {
        
        deft = 0.0;
        
    } else if (LADSPA_IS_HINT_DEFAULT_1(d)) {
        
        deft = 1.0;
        
    } else if (LADSPA_IS_HINT_DEFAULT_100(d)) {
        
        deft = 100.0;
        
    } else if (LADSPA_IS_HINT_DEFAULT_440(d)) {
        
//        deft = 440.0;
        deft = (float)Preferences::getInstance()->getTuningFrequency();
        
    } else {
        
        deft = minimum;
    }

//so it would happen twice if we did it here -- and e.g. DEFAULT_440
//doesn't want to be multiplied by the rate either
    
//    if (LADSPA_IS_HINT_SAMPLE_RATE(d)) {
//        deft *= m_sampleRate;
//    }

    return deft;
}

float
LADSPAPluginFactory::getPortQuantization(const LADSPA_Descriptor *descriptor, int port)
{
    int displayHint = getPortDisplayHint(descriptor, port);
    if (displayHint & PortHint::Toggled) {
        return float(lrintf(getPortMaximum(descriptor, port)) - 
                     lrintf(getPortMinimum(descriptor, port)));
    }
    if (displayHint & PortHint::Integer) {
        return 1.0;
    }
    return 0.0;
}

int
LADSPAPluginFactory::getPortDisplayHint(const LADSPA_Descriptor *descriptor, int port)
{
    LADSPA_PortRangeHintDescriptor d =
        descriptor->PortRangeHints[port].HintDescriptor;
    int hint = PortHint::NoHint;

    if (LADSPA_IS_HINT_TOGGLED(d)) hint |= PortHint::Toggled;
    if (LADSPA_IS_HINT_INTEGER(d)) hint |= PortHint::Integer;
    if (LADSPA_IS_HINT_LOGARITHMIC(d)) hint |= PortHint::Logarithmic;

    return hint;
}


std::shared_ptr<RealTimePluginInstance>
LADSPAPluginFactory::instantiatePlugin(QString identifier,
                                       int instrument,
                                       int position,
                                       sv_samplerate_t sampleRate,
                                       int blockSize,
                                       int channels)
{
    Profiler profiler("LADSPAPluginFactory::instantiatePlugin");

    const LADSPA_Descriptor *descriptor = getLADSPADescriptor(identifier);

    if (descriptor) {

        auto instance =
            std::shared_ptr<RealTimePluginInstance>
            (new LADSPAPluginInstance
             (this, instrument, identifier, position,
              sampleRate, blockSize, channels, descriptor));

        m_instances.insert(instance);

#ifdef DEBUG_LADSPA_PLUGIN_FACTORY
        SVDEBUG << "LADSPAPluginFactory::instantiatePlugin("
                  << identifier << ": now have " << m_instances.size() << " instances" << endl;
#endif

        return instance;
    }

    return nullptr;
}

const LADSPA_Descriptor *
LADSPAPluginFactory::getLADSPADescriptor(QString identifier)
{
    QString type, soname, label;
    PluginIdentifier::parseIdentifier(identifier, type, soname, label);

    if (m_libraryHandles.find(soname) == m_libraryHandles.end()) {
        loadLibrary(soname);
        if (m_libraryHandles.find(soname) == m_libraryHandles.end()) {
            SVCERR << "WARNING: LADSPAPluginFactory::getLADSPADescriptor: loadLibrary failed for " << soname << endl;
            return nullptr;
        }
    }

    void *libraryHandle = m_libraryHandles[soname];

    LADSPA_Descriptor_Function fn = (LADSPA_Descriptor_Function)
        DLSYM(libraryHandle, "ladspa_descriptor");

    if (!fn) {
        SVCERR << "WARNING: LADSPAPluginFactory::getLADSPADescriptor: No descriptor function in library " << soname << endl;
        return nullptr;
    }

    const LADSPA_Descriptor *descriptor = nullptr;
    
    int index = 0;
    while ((descriptor = fn(index))) {
        if (descriptor->Label == label) return descriptor;
        ++index;
    }

    SVCERR << "WARNING: LADSPAPluginFactory::getLADSPADescriptor: No such plugin as " << label << " in library " << soname << endl;

    return nullptr;
}

void
LADSPAPluginFactory::loadLibrary(QString soName)
{
    void *libraryHandle = DLOPEN(soName, RTLD_NOW);
    if (libraryHandle) {
        m_libraryHandles[soName] = libraryHandle;
        SVDEBUG << "LADSPAPluginFactory::loadLibrary: Loaded library \"" << soName << "\"" << endl;
        return;
    }

    if (QFileInfo(soName).exists()) {
        DLERROR();
        SVCERR << "LADSPAPluginFactory::loadLibrary: Library \"" << soName << "\" exists, but failed to load it" << endl;
        return;
    }

    std::vector<QString> pathList = getPluginPath();

    QString fileName = QFile(soName).fileName();
    QString base = QFileInfo(soName).baseName();

    for (std::vector<QString>::iterator i = pathList.begin();
         i != pathList.end(); ++i) {
        
#ifdef DEBUG_LADSPA_PLUGIN_FACTORY
        SVDEBUG << "Looking at: " << (*i) << endl;
#endif

        QDir dir(*i, PLUGIN_GLOB,
                 QDir::Name | QDir::IgnoreCase,
                 QDir::Files | QDir::Readable);

        if (QFileInfo(dir.filePath(fileName)).exists()) {
#ifdef DEBUG_LADSPA_PLUGIN_FACTORY
            SVDEBUG << "Loading: " << fileName << endl;
#endif
            libraryHandle = DLOPEN(dir.filePath(fileName), RTLD_NOW);
            if (libraryHandle) {
                m_libraryHandles[soName] = libraryHandle;
                return;
            }
        }

        for (unsigned int j = 0; j < dir.count(); ++j) {
            QString file = dir.filePath(dir[j]);
            if (QFileInfo(file).baseName() == base) {
#ifdef DEBUG_LADSPA_PLUGIN_FACTORY
                SVDEBUG << "Loading: " << file << endl;
#endif
                libraryHandle = DLOPEN(file, RTLD_NOW);
                if (libraryHandle) {
                    m_libraryHandles[soName] = libraryHandle;
                    return;
                }
            }
        }
    }

    SVCERR << "LADSPAPluginFactory::loadLibrary: Failed to locate plugin library \"" << soName << "\"" << endl;
}

void
LADSPAPluginFactory::unloadLibrary(QString soName)
{
    LibraryHandleMap::iterator li = m_libraryHandles.find(soName);
    if (li != m_libraryHandles.end()) {
//        SVDEBUG << "unloading " << soname << endl;
        DLCLOSE(m_libraryHandles[soName]);
        m_libraryHandles.erase(li);
    }
}

void
LADSPAPluginFactory::unloadUnusedLibraries()
{
    std::set<std::weak_ptr<RealTimePluginInstance>,
             std::owner_less<std::weak_ptr<RealTimePluginInstance>>> toRemove;

    std::set<QString> soNamesInUse;
    
    for (auto wp: m_instances) {
        if (auto p = wp.lock()) {
            QString itype, isoname, ilabel;
            PluginIdentifier::parseIdentifier(p->getPluginIdentifier(),
                                              itype, isoname, ilabel);
            soNamesInUse.insert(isoname);
        } else {
            toRemove.insert(wp);
        }
    }

    for (auto wp: toRemove) {
        m_instances.erase(wp);
    }

    std::vector<QString> toUnload;
    
    for (auto i = m_libraryHandles.begin();
         i != m_libraryHandles.end(); ++i) {

        if (soNamesInUse.find(i->first) == soNamesInUse.end()) {
            toUnload.push_back(i->first);
        }
    }

    for (auto soname: toUnload) {
        if (soname != PluginIdentifier::BUILTIN_PLUGIN_SONAME) {
            unloadLibrary(soname);
        }
    }
}


// It is only later, after they've gone,
// I realize they have delivered a letter.
// It's a letter from my wife.  "What are you doing
// there?" my wife asks.  "Are you drinking?"
// I study the postmark for hours.  Then it, too, begins to fade.
// I hope someday to forget all this.


std::vector<QString>
LADSPAPluginFactory::getPluginPath()
{
    std::vector<QString> pathList;
    string path;

    (void)getEnvUtf8("LADSPA_PATH", path);

    if (path == "") {

        path = DEFAULT_LADSPA_PATH;

        string home;
        if (getEnvUtf8("HOME", home)) {
            string::size_type f;
            while ((f = path.find("$HOME")) != string::npos &&
                   f < path.length()) {
                path.replace(f, 5, home);
            }
        }

#ifdef _WIN32
        string pfiles;
        if (!getEnvUtf8("ProgramFiles", pfiles)) {
            pfiles = "C:\\Program Files";
        }

        string::size_type f;
        while ((f = path.find("%ProgramFiles%")) != string::npos &&
               f < path.length()) {
            path.replace(f, 14, pfiles);
        }
#endif
    }

    string::size_type index = 0, newindex = 0;

    while ((newindex = path.find(PATH_SEPARATOR, index)) < path.size()) {
        pathList.push_back(path.substr(index, newindex - index).c_str());
        index = newindex + 1;
    }
    
    pathList.push_back(path.substr(index).c_str());

    return pathList;
}


std::vector<QString>
LADSPAPluginFactory::getLRDFPath(QString &baseUri)
{
    std::vector<QString> lrdfPaths;

#ifdef HAVE_LRDF
    std::vector<QString> pathList = getPluginPath();

    lrdfPaths.push_back("/usr/local/share/ladspa/rdf");
    lrdfPaths.push_back("/usr/share/ladspa/rdf");

    for (std::vector<QString>::iterator i = pathList.begin();
         i != pathList.end(); ++i) {
        lrdfPaths.push_back(*i + "/rdf");
    }

    baseUri = LADSPA_BASE;
#else
    baseUri = "";
#endif

    return lrdfPaths;
}    

void
LADSPAPluginFactory::discoverPlugins()
{
    Profiler profiler("LADSPAPluginFactory::discoverPlugins");

    std::vector<QString> pathList = getPluginPath();

//    SVDEBUG << "LADSPAPluginFactory::discoverPlugins - "
//              << "discovering plugins; path is ";
//    for (std::vector<QString>::iterator i = pathList.begin();
//         i != pathList.end(); ++i) {
//        SVDEBUG << "[" << i-<< "] ";
//    }
//    SVDEBUG << endl;

#ifdef HAVE_LRDF
    // read the description files 
    //
    QString baseUri;
    std::vector<QString> lrdfPaths = getLRDFPath(baseUri);

    bool haveSomething = false;

    for (size_t i = 0; i < lrdfPaths.size(); ++i) {
        QDir dir(lrdfPaths[i], "*.rdf;*.rdfs");
        for (unsigned int j = 0; j < dir.count(); ++j) {
            if (!lrdf_read_file(QString("file:" + lrdfPaths[i] + "/" + dir[j]).toStdString().c_str())) {
//                SVCERR << "LADSPAPluginFactory: read RDF file " << (lrdfPaths[i] + "/" + dir[j]) << endl;
                haveSomething = true;
            }
        }
    }

    if (haveSomething) {
        generateTaxonomy(baseUri + "Plugin", "");
    }
#endif // HAVE_LRDF

    generateFallbackCategories();

    auto candidates =
        PluginScan::getInstance()->getCandidateLibrariesFor(getPluginType());

    for (auto c: candidates) {
        discoverPluginsFrom(c.libraryPath);
    }
}

void
LADSPAPluginFactory::discoverPluginsFrom(QString soname)
{
    void *libraryHandle = DLOPEN(soname, RTLD_LAZY);

    if (!libraryHandle) {
        SVCERR << "WARNING: LADSPAPluginFactory::discoverPlugins: couldn't load plugin library "
                  << soname << " - " << DLERROR() << endl;
        return;
    }

    LADSPA_Descriptor_Function fn = (LADSPA_Descriptor_Function)
        DLSYM(libraryHandle, "ladspa_descriptor");

    if (!fn) {
        SVCERR << "WARNING: LADSPAPluginFactory::discoverPlugins: No descriptor function in " << soname << endl;
        return;
    }

    const LADSPA_Descriptor *descriptor = nullptr;
    
    int index = 0;
    while ((descriptor = fn(index))) {

        RealTimePluginDescriptor rtd;
        rtd.name = descriptor->Name;
        rtd.label = descriptor->Label;
        rtd.maker = descriptor->Maker;
        rtd.copyright = descriptor->Copyright;
        rtd.category = "";
        rtd.isSynth = false;
        rtd.parameterCount = 0;
        rtd.audioInputPortCount = 0;
        rtd.audioOutputPortCount = 0;
        rtd.controlOutputPortCount = 0;

        QString identifier = PluginIdentifier::createIdentifier
            ("ladspa", soname, descriptor->Label);

#ifdef HAVE_LRDF
        char *def_uri = nullptr;
        lrdf_defaults *defs = nullptr;
                
        if (m_lrdfTaxonomy[descriptor->UniqueID] != "") {
            m_taxonomy[identifier] = m_lrdfTaxonomy[descriptor->UniqueID];
//            SVCERR << "set id \"" << identifier << "\" to cat \"" << m_taxonomy[identifier] << "\" from LRDF" << endl;
//            cout << identifier << "::" << m_taxonomy[identifier] << endl;
        }

        QString category = m_taxonomy[identifier];
        
        if (category == "") {
            string name = rtd.name;
            if (name.length() > 4 &&
                name.substr(name.length() - 4) == " VST") {
                category = "VST effects";
                m_taxonomy[identifier] = category;
            }
        }
        
        rtd.category = category.toStdString();

//        SVCERR << "Plugin id is " << descriptor->UniqueID
//                  << ", category is \"" << (category ? category : QString("(none)"))
//                  << "\", name is " << descriptor->Name
//                  << ", label is " << descriptor->Label
//                  << endl;
        
        def_uri = lrdf_get_default_uri(descriptor->UniqueID);
        if (def_uri) {
            defs = lrdf_get_setting_values(def_uri);
        }

        unsigned int controlPortNumber = 1;
        
        for (int i = 0; i < (int)descriptor->PortCount; i++) {
            
            if (LADSPA_IS_PORT_CONTROL(descriptor->PortDescriptors[i])) {
                
                if (def_uri && defs) {
                    
                    for (unsigned int j = 0; j < defs->count; j++) {
                        if (defs->items[j].pid == controlPortNumber) {
//                            SVCERR << "Default for this port (" << defs->items[j].pid << ", " << defs->items[j].label << ") is " << defs->items[j].value << "; applying this to port number " << i << " with name " << descriptor->PortNames[i] << endl;
                            m_portDefaults[descriptor->UniqueID][i] =
                                defs->items[j].value;
                        }
                    }
                }
                
                ++controlPortNumber;
            }
        }
#endif // HAVE_LRDF

        for (int i = 0; i < (int)descriptor->PortCount; i++) {
            if (LADSPA_IS_PORT_CONTROL(descriptor->PortDescriptors[i])) {
                if (LADSPA_IS_PORT_INPUT(descriptor->PortDescriptors[i])) {
                    ++rtd.parameterCount;
                } else {
                    if (strcmp(descriptor->PortNames[i], "latency") &&
                        strcmp(descriptor->PortNames[i], "_latency")) {
                        ++rtd.controlOutputPortCount;
                        rtd.controlOutputPortNames.push_back
                            (descriptor->PortNames[i]);
                    }
                }
            } else {
                if (LADSPA_IS_PORT_INPUT(descriptor->PortDescriptors[i])) {
                    ++rtd.audioInputPortCount;
                } else if (LADSPA_IS_PORT_OUTPUT(descriptor->PortDescriptors[i])) {
                    ++rtd.audioOutputPortCount;
                }
            }
        }

        m_identifiers.push_back(identifier);

        m_libraries[identifier] = soname;

        m_rtDescriptors[identifier] = rtd;

        ++index;
    }

    if (DLCLOSE(libraryHandle) != 0) {
        SVCERR << "WARNING: LADSPAPluginFactory::discoverPlugins - can't unload " << libraryHandle << endl;
        return;
    }
}

void
LADSPAPluginFactory::generateFallbackCategories()
{
    std::vector<QString> pluginPath = getPluginPath();
    std::vector<QString> path;

    for (size_t i = 0; i < pluginPath.size(); ++i) {
        if (pluginPath[i].contains("/lib/")) {
            QString p(pluginPath[i]);
            path.push_back(p);
            p.replace("/lib/", "/share/");
            path.push_back(p);
//            SVDEBUG << "LADSPAPluginFactory::generateFallbackCategories: path element " << p << endl;
        }
        path.push_back(pluginPath[i]);
//        SVDEBUG << "LADSPAPluginFactory::generateFallbackCategories: path element " << pluginPath[i] << endl;
    }

    for (size_t i = 0; i < path.size(); ++i) {

        QDir dir(path[i], "*.cat");

//        SVDEBUG << "LADSPAPluginFactory::generateFallbackCategories: directory " << path[i] << " has " << dir.count() << " .cat files" << endl;
        for (unsigned int j = 0; j < dir.count(); ++j) {

            QFile file(path[i] + "/" + dir[j]);

//            SVDEBUG << "LADSPAPluginFactory::generateFallbackCategories: about to open " << (path[i]+ "/" + dir[j]) << endl;

            if (file.open(QIODevice::ReadOnly)) {
//                    cerr << "...opened" << endl;
                QTextStream stream(&file);
                QString line;

                while (!stream.atEnd()) {
                    line = stream.readLine();
//                    cerr << "line is: \"" << line << "\"" << endl;
                    QString id = PluginIdentifier::canonicalise
                        (line.section("::", 0, 0));
                    QString cat = line.section("::", 1, 1);
                    m_taxonomy[id] = cat;
//                    cerr << "set id \"" << id << "\" to cat \"" << cat << "\"" << endl;
                }
            }
        }
    }
}    

void
LADSPAPluginFactory::generateTaxonomy(QString uri, QString base)
{
#ifdef HAVE_LRDF
    lrdf_uris *uris = lrdf_get_instances(uri.toStdString().c_str());

    if (uris != nullptr) {
        for (unsigned int i = 0; i < uris->count; ++i) {
            m_lrdfTaxonomy[lrdf_get_uid(uris->items[i])] = base;
        }
        lrdf_free_uris(uris);
    }

    uris = lrdf_get_subclasses(uri.toStdString().c_str());

    if (uris != nullptr) {
        for (unsigned int i = 0; i < uris->count; ++i) {
            char *label = lrdf_get_label(uris->items[i]);
            generateTaxonomy(uris->items[i],
                             base + (base.length() > 0 ? " > " : "") + label);
        }
        lrdf_free_uris(uris);
    }
#else
    // avoid unused parameter
    (void)uri;
    (void)base;
#endif
}
    
QString
LADSPAPluginFactory::getPluginCategory(QString identifier)
{
    return m_taxonomy[identifier];
}