MidiInReader.cc

Go to the documentation of this file.

#include "MidiInReader.hh"
#include "MidiInConnector.hh"
#include "PlugException.hh"
#include "EventDistributor.hh"
#include "Scheduler.hh"
#include "FileOperations.hh"
#include "serialize.hh"
#include <cstdio>
#include <cerrno>
#include <cstring>

using std::string;

namespace openmsx {

MidiInReader::MidiInReader(EventDistributor& eventDistributor_,
                           Scheduler& scheduler_,
                           CommandController& commandController)
        : eventDistributor(eventDistributor_), scheduler(scheduler_)
        , readFilenameSetting(
                commandController, "midi-in-readfilename",
                "filename of the file where the MIDI input is read from",
                "/dev/midi")
{
        eventDistributor.registerEventListener(OPENMSX_MIDI_IN_READER_EVENT, *this);
}

MidiInReader::~MidiInReader()
{
        eventDistributor.unregisterEventListener(OPENMSX_MIDI_IN_READER_EVENT, *this);
}

// Pluggable
void MidiInReader::plugHelper(Connector& connector_, EmuTime::param /*time*/)
{
        file = FileOperations::openFile(readFilenameSetting.getString().str(), "rb");
        if (!file) {
                throw PlugException("Failed to open input: ", strerror(errno));
        }

        auto& midiConnector = static_cast<MidiInConnector&>(connector_);
        midiConnector.setDataBits(SerialDataInterface::DATA_8); // 8 data bits
        midiConnector.setStopBits(SerialDataInterface::STOP_1); // 1 stop bit
        midiConnector.setParityBit(false, SerialDataInterface::EVEN); // no parity

        setConnector(&connector_); // base class will do this in a moment,
                                   // but thread already needs it
        thread = std::thread([this]() { run(); });
}

void MidiInReader::unplugHelper(EmuTime::param /*time*/)
{
        poller.abort();
        thread.join();
        file.reset();
}

const string& MidiInReader::getName() const
{
        static const string name("midi-in-reader");
        return name;
}

string_view MidiInReader::getDescription() const
{
        return "MIDI in file reader. Sends data from an input file to the "
               "MIDI port it is connected to. The filename is set with "
               "the 'midi-in-readfilename' setting.";
}


void MidiInReader::run()
{
        byte buf;
        if (!file) return;
        while (true) {
#ifndef _WIN32
                if (poller.poll(fileno(file.get()))) {
                        break;
                }
#endif
                size_t num = fread(&buf, 1, 1, file.get());
                if (poller.aborted()) {
                        break;
                }
                if (num != 1) {
                        continue;
                }
                assert(isPluggedIn());

                {
                        std::lock_guard<std::mutex> lock(mutex);
                        queue.push_back(buf);
                }
                eventDistributor.distributeEvent(
                        std::make_shared<SimpleEvent>(OPENMSX_MIDI_IN_READER_EVENT));
        }
}

// MidiInDevice
void MidiInReader::signal(EmuTime::param time)
{
        auto* conn = static_cast<MidiInConnector*>(getConnector());
        if (!conn->acceptsData()) {
                std::lock_guard<std::mutex> lock(mutex);
                queue.clear();
                return;
        }
        if (!conn->ready()) {
                return;
        }

        byte data;
        {
                std::lock_guard<std::mutex> lock(mutex);
                if (queue.empty()) return;
                data = queue.pop_front();
        }
        conn->recvByte(data, time);
}

// EventListener
int MidiInReader::signalEvent(const std::shared_ptr<const Event>& /*event*/)
{
        if (isPluggedIn()) {
                signal(scheduler.getCurrentTime());
        } else {
                std::lock_guard<std::mutex> lock(mutex);
                queue.clear();
        }
        return 0;
}


template<typename Archive>
void MidiInReader::serialize(Archive& /*ar*/, unsigned /*version*/)
{
        // don't try to resume a previous logfile (see PrinterPortLogger)
}
INSTANTIATE_SERIALIZE_METHODS(MidiInReader);
REGISTER_POLYMORPHIC_INITIALIZER(Pluggable, MidiInReader, "MidiInReader");

} // namespace openmsx