TheGrandVisualizerShow/jackclient.c

//Standard lib
#include <string.h> //memcpy
#include <stdio.h> //print error messages
#include <unistd.h>


//Third party
#include <jack/jack.h>
#include <jack/midiport.h>
#include <jack/ringbuffer.h>
#include <jack/metadata.h>

//Our own files
#include "jackclient.h"
#include "constants.h"
#include "programstate.h"

extern ProgramState programState;

static jack_client_t* client;
//static jack_ringbuffer_t *ringbuffer = NULL;

jack_ringbuffer_t *allRingbuffers[VIS_PORTS];
jack_port_t *allPorts[VIS_PORTS];

static pthread_mutex_t msg_thread_lock = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t data_ready = PTHREAD_COND_INITIALIZER;

#define RBSIZE 512

typedef struct {
    uint8_t  buffer[128];
    uint32_t size;
} midimsg;


int process (jack_nframes_t frames, void* arg) {
    void* buffer;
    jack_nframes_t N;
    jack_nframes_t i;
    jack_port_t* port;
    jack_ringbuffer_t* rb=NULL;

    for (int portnum=0; portnum<VIS_PORTS; portnum++) {
        port = allPorts[portnum];
        rb = allRingbuffers[portnum];
        buffer = jack_port_get_buffer (port, frames);
        //assert (buffer);

        N = jack_midi_get_event_count (buffer);
        for (int i = 0; i < N; ++i) {
            jack_midi_event_t event;
            int r;

            r = jack_midi_event_get (&event, buffer, i);

            if (r == 0 && jack_ringbuffer_write_space(rb) >= sizeof(midimsg)) {
                midimsg message;
                message.size = event.size;
                memcpy (message.buffer, event.buffer, MAX(sizeof(message.buffer), event.size));
                jack_ringbuffer_write (rb, (void *) &message, sizeof(midimsg));
            }
        }
    }


    if (pthread_mutex_trylock (&msg_thread_lock) == 0) {
        pthread_cond_signal (&data_ready);
        pthread_mutex_unlock (&msg_thread_lock);
    }

    return 0;
}

static void handleMessage (Note *allGUINotes, int portnum, midimsg* event) {
    if (event->size == 0) {
        return;
    }

    uint8_t type = event->buffer[0] & 0xf0;
    uint8_t channel = event->buffer[0] & 0xf;
    Note * note;

    switch (type) {
        case 0x90:
            //assert (event->size == 3);
            //printf (" note on  (channel %2d): pitch %3d, velocity %3d\n", channel, event->buffer[1], event->buffer[2]);
            programState.portActivity[portnum] += 1;
            note = &allGUINotes[portnum*128 + event->buffer[1]];
            note->active = 1;
            note->countdown = 1.0f;
            note->velocity = event->buffer[2];
            note->pitch = event->buffer[1];
            note->port = portnum;
            break;
        case 0x80:
            //assert (event->size == 3);
            //printf (" note off (channel %2d): pitch %3d, velocity %3d\n", channel, event->buffer[1], event->buffer[2]);
            programState.portActivity[portnum] -= 1;
            if (programState.portActivity[portnum] < 1) { programState.portActivity[portnum] = 0;}
            note = &allGUINotes[portnum*128 + event->buffer[1]];
            note->countdown = 0.999f; //GUI will reduce that to 0 on its own as fade-out effect
            //Do NOT set to inactive. Note-Off triggers a graphical fadeout, only when that is over it is inactive.
            break;
        //case 0xb0:
            //assert (event->size == 3);
            //printf (" control change (channel %2d): controller %3d, value %3d", channel, event->buffer[1], event->buffer[2]);
        //    break;
        default:
            break;
    }
}

void mainLoop_processMidiMessages(Note *allGUINotes) {

    for (int portnum=0; portnum<VIS_PORTS; portnum++) {
        int mqlen = jack_ringbuffer_read_space (allRingbuffers[portnum]) / sizeof(midimsg);
        for (int i=0; i < mqlen; ++i) {
            size_t j;
            midimsg message;
            jack_ringbuffer_read(allRingbuffers[portnum], (char*) &message, sizeof(midimsg));
            handleMessage (allGUINotes, portnum, &message);
        }
    }
    pthread_cond_wait (&data_ready, &msg_thread_lock);

}

void mainLoop_collectTimingAndTransportInProgramState() {
    jack_position_t pos;
    jack_transport_state_t state = jack_transport_query(client, &pos);

    int totalSeconds = pos.frame / pos.frame_rate;
    int hours = totalSeconds / 3600; //int devision drops decimal
    int minutes = totalSeconds / 60 % 60;
    int seconds = totalSeconds % 60;

    snprintf(programState.clockString, (sizeof(char) * 255), "%i:%02i:%02i ( %is )", hours, minutes, seconds, totalSeconds);

    programState.transportRolling = state != JackTransportStopped;

    if (pos.beats_per_minute > 1.0d) { //comparing to 0 does not work
        programState.bpm = pos.beats_per_minute;
    }
    else
    {
        programState.bpm = 120.0d;
    }

}


void ourConnectCallback(jack_port_id_t a, jack_port_id_t b, int connect, void *arg) {

    //On each connection change go through our ports and check the situation.
    //Only the first port is enough for our purposes

    //TODO: optimisation opportunity: keep a list of our port ids and check that first.

    for (int portnum=0; portnum<VIS_PORTS; portnum++) {
        const char** connectedPorts;
        connectedPorts = jack_port_get_connections(allPorts[portnum]);

        if (connectedPorts && connectedPorts[0])
        {
            //We could use connectedPorts[0] directly as a name, this is the real portname.
            //However, we try to get a pretty name from Jack Metadata first
            jack_port_t * externalPort;
            externalPort = jack_port_by_name(client, connectedPorts[0]);
            jack_uuid_t externalId = jack_port_uuid(externalPort);
            char * externalPrettyName;
            char * externalType;
            int returnCode = jack_get_property(externalId, JACK_METADATA_PRETTY_NAME, &externalPrettyName, &externalType);
            if (!returnCode && externalPrettyName) {
                //const char * prettyPortConst = externalPrettyName;
                //strcpy(prettyPortNameCopy, externalPrettyName); //strcpy is const -> non-const
                programState.connectedPortNames[portnum] = externalPrettyName;
                //if (externalPrettyName) jack_free(externalPrettyName); //TODO: If I free that the name either vanishes, segfaults, is wrong or garbage or it is always the same. No matter what string copy, conversion etc. I tried
                if (externalType) jack_free(externalType);
            }
            else { // No Metadata for this port found
                programState.connectedPortNames[portnum] = connectedPorts[0];
            }
        }
        else
        {
            programState.connectedPortNames[portnum] = ""; //Reset
        }
        jack_free(connectedPorts);
    }

}

void createJackClient() {

    int errorCode;

    client = jack_client_open (programState.name, JackNullOption, NULL);
    if (client == NULL) {
        fprintf (stderr, "Could not create JACK client.\n");
        exit (EXIT_FAILURE);
    }

    jack_set_process_callback (client, process, 0);

    for (int portnum=0; portnum<VIS_PORTS;portnum++) {
        allRingbuffers[portnum] = jack_ringbuffer_create (RBSIZE * sizeof(midimsg)); //Communicate between RT and Non-RT
        char name[64];
        sprintf(name, "%i", portnum);
        allPorts[portnum] = jack_port_register (client, name, JACK_DEFAULT_MIDI_TYPE, JackPortIsInput, 0);
        if (allPorts[portnum] == NULL) {
            fprintf (stderr, "Could not register port.\n");
            exit (EXIT_FAILURE);
        }
    }

    //Callbacks must be registered before activating the client
    errorCode = jack_set_port_connect_callback(client, ourConnectCallback, 0);
    if (errorCode != 0) {
        fprintf (stderr, "Could not register port registration callback.\n");
        exit (EXIT_FAILURE);
    }

    //Now activate
    errorCode = jack_activate (client);
    if (errorCode != 0) {
        fprintf (stderr, "Could not activate client.\n");
        exit (EXIT_FAILURE);
    }


}

void closeJackClient() {
    pthread_mutex_unlock (&msg_thread_lock);
    jack_deactivate (client);
    jack_client_close (client);
    for (int portnum=0; portnum<VIS_PORTS;portnum++) {
        jack_ringbuffer_free (allRingbuffers[portnum]);
    }
    printf("Jack Client closed succesfully\n");
}

void seekToStart() {
    jack_transport_locate(client, 0);
}

void toggleTransport() {
    //This is only the active toggle from our side. No reaction to external transport

    //Called from non-rt thread
    jack_position_t pos;
    jack_transport_state_t state = jack_transport_query(client, &pos);

    if (state == JackTransportStopped) {
        jack_transport_start(client);
    }
    else if (state == JackTransportStarting) {
        //Waiting for sync ready
    }
    else {
        jack_transport_stop(client);
    }
}