rtmidi.cpp

Mobile STK for Symbian OS V0.1

  // Set up the ALSA sequencer client.
	snd_seq_t *seq;
  int result = snd_seq_open(&seq, "default", SND_SEQ_OPEN_DUPLEX, SND_SEQ_NONBLOCK);
  if ( result < 0 ) {
    errorString_ = "RtMidiIn::initialize: error creating ALSA sequencer input client object.";
    error( RtError::DRIVER_ERROR );
	}

  // Set client name.
  snd_seq_set_client_name(seq, "RtMidi Input Client");

  // Save our api-specific connection information.
  AlsaMidiData *data = (AlsaMidiData *) new AlsaMidiData;
  data->seq = seq;
  data->vport = -1;
  apiData_ = (void *) data;
  inputData_.apiData = (void *) data;

  // Create the input queue
  data->queue_id = snd_seq_alloc_named_queue(seq, "RtMidi Queue");
  // Set arbitrary tempo (mm=100) and resolution (240)
  snd_seq_queue_tempo_t *qtempo;
  snd_seq_queue_tempo_alloca(&qtempo);
  snd_seq_queue_tempo_set_tempo(qtempo, 600000);
  snd_seq_queue_tempo_set_ppq(qtempo, 240);
  snd_seq_set_queue_tempo(data->seq, data->queue_id, qtempo);
  snd_seq_drain_output(data->seq);
}

// This function is used to count or get the pinfo structure for a given port number.
unsigned int portInfo( snd_seq_t *seq, snd_seq_port_info_t *pinfo, unsigned int type, int portNumber )
{
	snd_seq_client_info_t *cinfo;
  int client;
  int count = 0;
	snd_seq_client_info_alloca( &cinfo );

	snd_seq_client_info_set_client( cinfo, -1 );
	while ( snd_seq_query_next_client( seq, cinfo ) >= 0 ) {
    client = snd_seq_client_info_get_client( cinfo );
    if ( client == 0 ) continue;
		// Reset query info
		snd_seq_port_info_set_client( pinfo, client );
		snd_seq_port_info_set_port( pinfo, -1 );
		while ( snd_seq_query_next_port( seq, pinfo ) >= 0 ) {
      if ( !PORT_TYPE( pinfo, type ) )  continue;
      if ( count == portNumber ) return 1;
      count++;
		}
	}

  // If a negative portNumber was used, return the port count.
  if ( portNumber < 0 ) return count;
  return 0;
}

void RtMidiIn :: openPort( unsigned int portNumber )
{
  if ( connected_ ) {
    errorString_ = "RtMidiIn::openPort: a valid connection already exists!";
    error( RtError::WARNING );
    return;
  }

  unsigned int nSrc = this->getPortCount();
  if (nSrc < 1) {
    errorString_ = "RtMidiIn::openPort: no MIDI input sources found!";
    error( RtError::NO_DEVICES_FOUND );
  }

	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );
  std::ostringstream ost;
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_READ|SND_SEQ_PORT_CAP_SUBS_READ, (int) portNumber ) == 0 ) {
    ost << "RtMidiIn::openPort: the 'portNumber' argument (" << portNumber << ") is invalid.";
    errorString_ = ost.str();
    error( RtError::INVALID_PARAMETER );
  }


  snd_seq_addr_t sender, receiver;
  sender.client = snd_seq_port_info_get_client( pinfo );
  sender.port = snd_seq_port_info_get_port( pinfo );
  receiver.client = snd_seq_client_id( data->seq );
  if ( data->vport < 0 ) {
    snd_seq_port_info_set_client( pinfo, 0 );
    snd_seq_port_info_set_port( pinfo, 0 );
    snd_seq_port_info_set_capability( pinfo,
                                      SND_SEQ_PORT_CAP_WRITE |
                                      SND_SEQ_PORT_CAP_SUBS_WRITE );
    snd_seq_port_info_set_type( pinfo,
                                SND_SEQ_PORT_TYPE_MIDI_GENERIC |
                                SND_SEQ_PORT_TYPE_APPLICATION );
    snd_seq_port_info_set_midi_channels(pinfo, 16);
    snd_seq_port_info_set_timestamping(pinfo, 1);
    snd_seq_port_info_set_timestamp_real(pinfo, 1);    
    snd_seq_port_info_set_timestamp_queue(pinfo, data->queue_id);
    snd_seq_port_info_set_name(pinfo, "RtMidi Input");
    data->vport = snd_seq_create_port(data->seq, pinfo);
  
    if ( data->vport < 0 ) {
      errorString_ = "RtMidiIn::openPort: ALSA error creating input port.";
      error( RtError::DRIVER_ERROR );
    }
  }

  receiver.port = data->vport;

  // Make subscription
  snd_seq_port_subscribe_malloc( &data->subscription );
  snd_seq_port_subscribe_set_sender(data->subscription, &sender);
  snd_seq_port_subscribe_set_dest(data->subscription, &receiver);
  if ( snd_seq_subscribe_port(data->seq, data->subscription) ) {
    errorString_ = "RtMidiIn::openPort: ALSA error making port connection.";
    error( RtError::DRIVER_ERROR );
  }

  if ( inputData_.doInput == false ) {
    // Start the input queue
    snd_seq_start_queue( data->seq, data->queue_id, NULL );
    snd_seq_drain_output( data->seq );
    // Start our MIDI input thread.
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
    pthread_attr_setschedpolicy(&attr, SCHED_OTHER);

    inputData_.doInput = true;
    int err = pthread_create(&data->thread, &attr, alsaMidiHandler, &inputData_);
    pthread_attr_destroy(&attr);
    if (err) {
      snd_seq_unsubscribe_port( data->seq, data->subscription );
      snd_seq_port_subscribe_free( data->subscription );
      inputData_.doInput = false;
      errorString_ = "RtMidiIn::openPort: error starting MIDI input thread!";
      error( RtError::THREAD_ERROR );
    }
  }

  connected_ = true;
}

void RtMidiIn :: openVirtualPort()
{
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( data->vport < 0 ) {
    snd_seq_port_info_t *pinfo;
    snd_seq_port_info_alloca( &pinfo );
    snd_seq_port_info_set_capability( pinfo,
				      SND_SEQ_PORT_CAP_WRITE |
				      SND_SEQ_PORT_CAP_SUBS_WRITE );
    snd_seq_port_info_set_type( pinfo,
				SND_SEQ_PORT_TYPE_MIDI_GENERIC |
				SND_SEQ_PORT_TYPE_APPLICATION );
    snd_seq_port_info_set_midi_channels(pinfo, 16);
    snd_seq_port_info_set_timestamping(pinfo, 1);
    snd_seq_port_info_set_timestamp_real(pinfo, 1);    
    snd_seq_port_info_set_timestamp_queue(pinfo, data->queue_id);
    snd_seq_port_info_set_name(pinfo, "RtMidi Input");
    data->vport = snd_seq_create_port(data->seq, pinfo);

    if ( data->vport < 0 ) {
      errorString_ = "RtMidiIn::openVirtualPort: ALSA error creating virtual port.";
      error( RtError::DRIVER_ERROR );
    }
  }

  if ( inputData_.doInput == false ) {
    // Start the input queue
    snd_seq_start_queue( data->seq, data->queue_id, NULL );
    snd_seq_drain_output( data->seq );
    // Start our MIDI input thread.
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
    pthread_attr_setschedpolicy(&attr, SCHED_OTHER);

    inputData_.doInput = true;
    int err = pthread_create(&data->thread, &attr, alsaMidiHandler, &inputData_);
    pthread_attr_destroy(&attr);
    if (err) {
      snd_seq_unsubscribe_port( data->seq, data->subscription );
      snd_seq_port_subscribe_free( data->subscription );
      inputData_.doInput = false;
      errorString_ = "RtMidiIn::openPort: error starting MIDI input thread!";
      error( RtError::THREAD_ERROR );
    }
  }
}

void RtMidiIn :: closePort( void )
{
  if ( connected_ ) {
    AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
    snd_seq_unsubscribe_port( data->seq, data->subscription );
    snd_seq_port_subscribe_free( data->subscription );
    // Stop the input queue
    snd_seq_stop_queue( data->seq, data->queue_id, NULL );
    snd_seq_drain_output( data->seq );
    connected_ = false;
  }
}

RtMidiIn :: ~RtMidiIn()
{
  // Close a connection if it exists.
  closePort();

  // Shutdown the input thread.
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( inputData_.doInput ) {
    inputData_.doInput = false;
    pthread_join( data->thread, NULL );
  }

  // Cleanup.
  if ( data->vport >= 0 ) snd_seq_delete_port( data->seq, data->vport );
  snd_seq_free_queue( data->seq, data->queue_id );
  snd_seq_close( data->seq );
  delete data;
}

unsigned int RtMidiIn :: getPortCount()
{
	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );

  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  return portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_READ|SND_SEQ_PORT_CAP_SUBS_READ, -1 );
}

std::string RtMidiIn :: getPortName( unsigned int portNumber )
{
	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );

  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_READ|SND_SEQ_PORT_CAP_SUBS_READ, (int) portNumber ) ) {
    std::string stringName = std::string( snd_seq_port_info_get_name( pinfo ) );
    return stringName;
  }

  // If we get here, we didn't find a match.
  errorString_ = "RtMidiIn::getPortName: error looking for port name!";
  error( RtError::INVALID_PARAMETER );
  return 0;
}

//*********************************************************************//
//  API: LINUX ALSA
//  Class Definitions: RtMidiOut
//*********************************************************************//

unsigned int RtMidiOut :: getPortCount()
{
	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );

  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  return portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_WRITE|SND_SEQ_PORT_CAP_SUBS_WRITE, -1 );
}

std::string RtMidiOut :: getPortName( unsigned int portNumber )
{
	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );

  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_WRITE|SND_SEQ_PORT_CAP_SUBS_WRITE, (int) portNumber ) ) {
    std::string stringName = std::string( snd_seq_port_info_get_name( pinfo ) );
    return stringName;
  }

  // If we get here, we didn't find a match.
  errorString_ = "RtMidiOut::getPortName: error looking for port name!";
  error( RtError::INVALID_PARAMETER );
  return 0;
}

void RtMidiOut :: initialize( void )
{
  // Set up the ALSA sequencer client.
	snd_seq_t *seq;
  int result = snd_seq_open(&seq, "default", SND_SEQ_OPEN_OUTPUT, 0);
  if ( result < 0 ) {
    errorString_ = "RtMidiOut::initialize: error creating ALSA sequencer client object.";
    error( RtError::DRIVER_ERROR );
	}

  // Set client name.
  snd_seq_set_client_name(seq, "RtMidi Output Client");

  // Save our api-specific connection information.
  AlsaMidiData *data = (AlsaMidiData *) new AlsaMidiData;
  data->seq = seq;
  data->vport = -1;
  data->bufferSize = 32;
  data->coder = 0;
  data->buffer = 0;
  result = snd_midi_event_new( data->bufferSize, &data->coder );
  if ( result < 0 ) {
    delete data;
    errorString_ = "RtMidiOut::initialize: error initializing MIDI event parser!\n\n";
    error( RtError::DRIVER_ERROR );
  }
  data->buffer = (unsigned char *) malloc( data->bufferSize );
  if ( data->buffer == NULL ) {
    delete data;
    errorString_ = "RtMidiOut::initialize: error allocating buffer memory!\n\n";
    error( RtError::MEMORY_ERROR );
  }
  snd_midi_event_init( data->coder );
  apiData_ = (void *) data;
}

void RtMidiOut :: openPort( unsigned int portNumber )
{
  if ( connected_ ) {
    errorString_ = "RtMidiOut::openPort: a valid connection already exists!";
    error( RtError::WARNING );
    return;
  }

  unsigned int nSrc = this->getPortCount();
  if (nSrc < 1) {
    errorString_ = "RtMidiOut::openPort: no MIDI output sources found!";
    error( RtError::NO_DEVICES_FOUND );
  }

	snd_seq_port_info_t *pinfo;
	snd_seq_port_info_alloca( &pinfo );
  std::ostringstream ost;
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( portInfo( data->seq, pinfo, SND_SEQ_PORT_CAP_WRITE|SND_SEQ_PORT_CAP_SUBS_WRITE, (int) portNumber ) == 0 ) {
    ost << "RtMidiOut::openPort: the 'portNumber' argument (" << portNumber << ") is invalid.";
    errorString_ = ost.str();
    error( RtError::INVALID_PARAMETER );
  }

  snd_seq_addr_t sender, receiver;
  receiver.client = snd_seq_port_info_get_client( pinfo );
  receiver.port = snd_seq_port_info_get_port( pinfo );
  sender.client = snd_seq_client_id( data->seq );

  if ( data->vport < 0 ) {
    data->vport = snd_seq_create_simple_port( data->seq, "RtMidi Output",
                                              SND_SEQ_PORT_CAP_READ|SND_SEQ_PORT_CAP_SUBS_READ,
                                              SND_SEQ_PORT_TYPE_MIDI_GENERIC );
    if ( data->vport < 0 ) {
      errorString_ = "RtMidiOut::openPort: ALSA error creating output port.";
      error( RtError::DRIVER_ERROR );
    }
  }

  sender.port = data->vport;

  // Make subscription
  snd_seq_port_subscribe_malloc( &data->subscription );
  snd_seq_port_subscribe_set_sender(data->subscription, &sender);
  snd_seq_port_subscribe_set_dest(data->subscription, &receiver);
  snd_seq_port_subscribe_set_time_update(data->subscription, 1);
  snd_seq_port_subscribe_set_time_real(data->subscription, 1);
  if ( snd_seq_subscribe_port(data->seq, data->subscription) ) {
    errorString_ = "RtMidiOut::openPort: ALSA error making port connection.";
    error( RtError::DRIVER_ERROR );
  }

  connected_ = true;
}

void RtMidiOut :: closePort( void )
{
  if ( connected_ ) {
    AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
    snd_seq_unsubscribe_port( data->seq, data->subscription );
    snd_seq_port_subscribe_free( data->subscription );
    connected_ = false;
  }
}

void RtMidiOut :: openVirtualPort()
{
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( data->vport < 0 ) {
    data->vport = snd_seq_create_simple_port( data->seq, "RtMidi Output",
                                              SND_SEQ_PORT_CAP_READ|SND_SEQ_PORT_CAP_SUBS_READ,
                                              SND_SEQ_PORT_TYPE_MIDI_GENERIC );

    if ( data->vport < 0 ) {
      errorString_ = "RtMidiOut::openVirtualPort: ALSA error creating virtual port.";
      error( RtError::DRIVER_ERROR );
    }
  }
}

RtMidiOut :: ~RtMidiOut()
{
  // Close a connection if it exists.
  closePort();

  // Cleanup.
  AlsaMidiData *data = static_cast<AlsaMidiData *> (apiData_);
  if ( data->vport >= 0 ) snd_seq_delete_port( data->seq, data->vport );
  if ( data->coder ) snd_midi_event_free( data->coder );
  if ( data->buffer ) free( data->buffer );
  snd_seq_close( data->seq );
  delete data;
}