annotate vamp-client/PluginStub.h @ 170:590b1a1fd955

More work on error and exception handling

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

  An API for audio analysis and feature extraction plugins.

  Centre for Digital Music, Queen Mary, University of London.
  Copyright 2006-2016 Chris Cannam and QMUL.
  
  Permission is hereby granted, free of charge, to any person
  obtaining a copy of this software and associated documentation
  files (the "Software"), to deal in the Software without
  restriction, including without limitation the rights to use, copy,
  modify, merge, publish, distribute, sublicense, and/or sell copies
  of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
  ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
  CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

  Except as contained in this notice, the names of the Centre for
  Digital Music; Queen Mary, University of London; and Chris Cannam
  shall not be used in advertising or otherwise to promote the sale,
  use or other dealings in this Software without prior written
  authorization.
*/

#ifndef PIPER_PLUGIN_STUB_H
#define PIPER_PLUGIN_STUB_H

#include <vamp-hostsdk/Plugin.h>
#include <vamp-hostsdk/PluginLoader.h>

#include "vamp-support/PluginStaticData.h"
#include "vamp-support/PluginConfiguration.h"

#include "PluginClient.h"

#include <cstdint>
#include <iostream>

namespace piper_vamp {
namespace client {

class PluginStub : public Vamp::Plugin
{
    enum State {
        Loaded, Configured, Finished, Failed
    };
    
public:
    PluginStub(PluginClient *client,
               std::string pluginKey,
               float inputSampleRate,
               int adapterFlags,
               PluginStaticData psd,
               PluginConfiguration defaultConfig) :
        Plugin(inputSampleRate),
        m_client(client),
        m_key(pluginKey),
        m_adapterFlags(adapterFlags),
        m_state(Loaded),
        m_psd(psd),
        m_defaultConfig(defaultConfig),
        m_config(defaultConfig)
    { }

    virtual ~PluginStub() {
        if (m_state != Finished && m_state != Failed) {
            try {
                (void)m_client->finish(this);
            } catch (const std::exception &e) {
                // Finish can throw, but our destructor must not
                std::cerr << "WARNING: PluginStub::~PluginStub: caught exception from finish(): " << e.what() << std::endl;
            }
        }
    }
    
    virtual std::string getIdentifier() const {
        return m_psd.basic.identifier;
    }

    virtual std::string getName() const {
        return m_psd.basic.name;
    }

    virtual std::string getDescription() const {
        return m_psd.basic.description;
    }

    virtual std::string getMaker() const {
        return m_psd.maker;
    }

    virtual std::string getCopyright() const {
        return m_psd.copyright;
    }

    virtual int getPluginVersion() const {
        return m_psd.pluginVersion;
    }

    virtual ParameterList getParameterDescriptors() const {
        return m_psd.parameters;
    }

    virtual float getParameter(std::string name) const {
        if (m_config.parameterValues.find(name) != m_config.parameterValues.end()) {
            return m_config.parameterValues.at(name);
        } else {
            return 0.f;
        }
    }

    virtual void setParameter(std::string name, float value) {
        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state != Loaded) {
            m_state = Failed;
            throw std::logic_error("Can't set parameter after plugin initialised");
        }
        m_config.parameterValues[name] = value;
    }

    virtual ProgramList getPrograms() const {
        return m_psd.programs;
    }

    virtual std::string getCurrentProgram() const {
        return m_config.currentProgram;
    }
    
    virtual void selectProgram(std::string program) {
        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state != Loaded) {
            m_state = Failed;
            throw std::logic_error("Can't select program after plugin initialised");
        }
        m_config.currentProgram = program;
    }

    virtual bool initialise(size_t inputChannels,
                            size_t stepSize,
                            size_t blockSize) {

        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state != Loaded) {
            m_state = Failed;
            throw std::logic_error("Plugin has already been initialised");
        }
        
        m_config.channelCount = int(inputChannels);
        m_config.stepSize = int(stepSize);
        m_config.blockSize = int(blockSize);

        try {
            m_outputs = m_client->configure(this, m_config);
        } catch (const std::exception &e) {
            m_state = Failed;
            throw;
        }

        if (!m_outputs.empty()) {
            m_state = Configured;
            return true;
        } else {
            return false;
        }
    }

    virtual void reset() {
        
        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state == Loaded) {
            // reset is a no-op if the plugin hasn't been initialised yet
            return;
        }

        try {
            m_client->reset(this, m_config);
        } catch (const std::exception &e) {
            m_state = Failed;
            throw;
        }

        m_state = Configured;
    }

    virtual InputDomain getInputDomain() const {
        return m_psd.inputDomain;
    }

    virtual size_t getPreferredBlockSize() const {
        return m_defaultConfig.blockSize;
    }

    virtual size_t getPreferredStepSize() const {
        return m_defaultConfig.stepSize;
    }

    virtual size_t getMinChannelCount() const {
        return m_psd.minChannelCount;
    }

    virtual size_t getMaxChannelCount() const {
        return m_psd.maxChannelCount;
    }

    virtual OutputList getOutputDescriptors() const {

        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state == Configured) {
            return m_outputs;
        }

        //!!! todo: figure out for which hosts (and adapters?) it may
        //!!! be a problem that the output descriptors are incomplete
        //!!! here. Any such hosts/adapters are broken, but I bet they
        //!!! exist
        
        OutputList staticOutputs;
        for (const auto &o: m_psd.basicOutputInfo) {
            OutputDescriptor od;
            od.identifier = o.identifier;
            od.name = o.name;
            od.description = o.description;
            staticOutputs.push_back(od);
        }
        return staticOutputs;
    }

    virtual FeatureSet process(const float *const *inputBuffers,
                               Vamp::RealTime timestamp) {

        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state == Loaded) {
            m_state = Failed;
            throw std::logic_error("Plugin has not been initialised");
        }
        if (m_state == Finished) {
            m_state = Failed;
            throw std::logic_error("Plugin has already been disposed of");
        }

        std::vector<std::vector<float> > vecbuf;
        for (int c = 0; c < m_config.channelCount; ++c) {
            vecbuf.push_back(std::vector<float>
                             (inputBuffers[c],
                              inputBuffers[c] + m_config.blockSize));
        }

        try {
            return m_client->process(this, vecbuf, timestamp);
        } catch (const std::exception &e) {
            m_state = Failed;
            throw;
        }
    }

    virtual FeatureSet getRemainingFeatures() {

        if (m_state == Failed) {
            throw std::logic_error("Plugin is in failed state");
        }
        if (m_state == Loaded) {
            m_state = Failed;
            throw std::logic_error("Plugin has not been configured");
        }
        if (m_state == Finished) {
            m_state = Failed;
            throw std::logic_error("Plugin has already been disposed of");
        }

        m_state = Finished;

        try {
            return m_client->finish(this);
        } catch (const std::exception &e) {
            m_state = Failed;
            throw;
        }
    }

    // Not Plugin methods, but needed by the PluginClient to support reloads:
    
    virtual float getInputSampleRate() const {
        return m_inputSampleRate;
    }

    virtual std::string getPluginKey() const {
        return m_key;
    }

    virtual int getAdapterFlags() const {
        return m_adapterFlags;
    }
    
private:
    PluginClient *m_client;
    std::string m_key;
    int m_adapterFlags;
    State m_state;
    PluginStaticData m_psd;
    OutputList m_outputs;
    PluginConfiguration m_defaultConfig;
    PluginConfiguration m_config;
};

}
}

#endif