common.c

   1 /*
   2  * Control JACK transport using MMC (MIDI)
   3  *
   4  * Copyright (c) 2006,2007,2008,2010 Nedko Arnaudov <nedko@arnaudov.name>
   5  * Copyright (c) 2008 Alex Montgomery <apmontgomery@gmail.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it under
   8  * the terms of the GNU General Public License as published by the Free Software
   9  * Foundation; version 2 of the License.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT ANY
  12  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA
  18  */
  19
  20 #include "common.h"
  21
  22 // exported globals
  23 int g_quit = 0; // a flag which will be set by our signal handler when it's time to exit
  24
  25 // globals used only here in common.c
  26 snd_seq_t* g_seq_ptr = NULL;
  27 jack_client_t* g_jack_client = NULL;
  28 struct pollfd* g_pollDescriptor = NULL;
  29 int g_numDescriptors = 0;
  30
  31 #if LASH_SUPPORT
  32 lash_client_t* g_lashc = NULL;
  33
  34 void init_lash(int argc, char* argv[])
  35 {
  36    /* LASH setup */
  37    g_lashc = lash_init( lash_extract_args(&argc, &argv), "jackctlmmc", 0, LASH_PROTOCOL_VERSION);
  38
  39    if (g_lashc == NULL)
  40    {
  41       printMMCMessage("Failed to connect to LASH. Session management will not occur.\n");
  42    }
  43
  44    // register JACK and ALSA clients with lash
  45    lash_alsa_client_id(g_lashc, snd_seq_client_id(g_seq_ptr));
  46    lash_jack_client_name(g_lashc, "jackctlmmc");
  47 }
  48
  49 void process_lash_event(lash_event_t * event_ptr)
  50 {
  51    enum LASH_Event_Type type;
  52    const char * str;
  53
  54    type = lash_event_get_type(event_ptr);
  55    str = lash_event_get_string(event_ptr);
  56
  57    switch (type)
  58    {
  59       case LASH_Quit:
  60          printMMCMessage("LASH_Quit received.\n");
  61          g_lashc = NULL;
  62          g_quit = 1;
  63          break;
  64       case LASH_Save_File:
  65       case LASH_Restore_File:
  66       case LASH_Save_Data_Set:
  67       default:
  68          printMMCMessage("LASH Event. Type = %u, string = \"%s\"\n",
  69                (unsigned int)type,
  70                (str == NULL)?"":str);
  71    }
  72 }
  73
  74 void process_lash_config(lash_config_t * config_ptr)
  75 {
  76    const char * key;
  77    const void * data;
  78    size_t data_size;
  79
  80    key = lash_config_get_key(config_ptr);
  81    data = lash_config_get_value(config_ptr);
  82    data_size = lash_config_get_value_size(config_ptr);
  83
  84    printMMCMessage("LASH Config. Key = \"%s\"\n", key);
  85 }
  86 #endif // LASH_SUPPORT
  87
  88 #if JACK_MIDI_SUPPORT
  89
  90 jack_port_t* g_jackMidiIn = NULL;
  91
  92 int jack_process_cb(jack_nframes_t numFrames, void* cbContext)
  93 {
  94    uint8_t* inBuffer = 0;
  95    int numMidiEvents = 0;
  96    jack_midi_event_t currEvent;
  97    int midiIndex = 0;
  98    MidiSettings* settings = (MidiSettings*) cbContext;
  99
 100    inBuffer = jack_port_get_buffer(g_jackMidiIn, numFrames);
 101    numMidiEvents = jack_midi_get_event_count(inBuffer);
 102
 103    for (midiIndex = 0; midiIndex < numMidiEvents; ++midiIndex)
 104    {
 105       jack_midi_event_get(&currEvent, inBuffer, midiIndex);
 106       handle_midi(currEvent.buffer, settings);
 107    }
 108
 109    return 0;
 110 }
 111
 112 int init_jack_midi(MidiSettings* settings)
 113 {
 114    int errorCode = 0;
 115
 116    errorCode = jack_set_process_callback(g_jack_client, &jack_process_cb, settings);
 117    g_jackMidiIn = jack_port_register(g_jack_client, "in", JACK_DEFAULT_MIDI_TYPE, JackPortIsInput | JackPortIsTerminal, 1024);
 118    return (errorCode == 0 && g_jackMidiIn != 0);
 119 }
 120 #endif // JACK_MIDI_SUPPORT
 121
 122 int init_alsa_sequencer(const char* appName)
 123 {
 124    snd_seq_port_info_t * seq_port_info = NULL;
 125    int ret = 0;
 126
 127    /* ALSA sequencer initialisation */
 128    ret = snd_seq_open( &g_seq_ptr, "default", SND_SEQ_OPEN_INPUT, 0);
 129    if (ret < 0)
 130       return ret;
 131
 132    // setup alsa sequencer port
 133    snd_seq_port_info_alloca(&seq_port_info);
 134    snd_seq_port_info_set_capability(seq_port_info, SND_SEQ_PORT_CAP_WRITE | SND_SEQ_PORT_CAP_SUBS_WRITE);
 135    snd_seq_port_info_set_type( seq_port_info, SND_SEQ_PORT_TYPE_APPLICATION);
 136    snd_seq_port_info_set_midi_channels(seq_port_info, 16);
 137    snd_seq_port_info_set_port_specified(seq_port_info, 1);
 138    snd_seq_port_info_set_name(seq_port_info, "midi in");
 139    snd_seq_port_info_set_port(seq_port_info, 0);
 140
 141    ret = snd_seq_create_port(g_seq_ptr, seq_port_info);
 142
 143    if (ret < 0)
 144       printMMCMessage("Error with alsa sequencer initialization, %s\n", snd_strerror(ret));
 145    else // all is well, register the sequencer with whatever name was passed in
 146    {
 147       snd_seq_set_client_name(g_seq_ptr, appName);
 148
 149       g_numDescriptors = snd_seq_poll_descriptors_count(g_seq_ptr, POLLIN);
 150       g_pollDescriptor = (struct pollfd *)malloc(g_numDescriptors * sizeof(struct pollfd));
 151       snd_seq_poll_descriptors(g_seq_ptr, g_pollDescriptor, g_numDescriptors, POLLIN);
 152    }
 153
 154    return ret;
 155 }
 156
 157 int init_jack(const char* appName)
 158 {
 159    jack_status_t status;
 160    g_jack_client = jack_client_open(appName, JackNoStartServer, &status);
 161
 162    if (!g_jack_client) // something went wrong
 163       return -1; // todo: check status to see exactly what happened
 164
 165    return 0;
 166 }
 167
 168 int activate_jack()
 169 {
 170    /* tell jack that we are ready to do our thing */
 171    return jack_activate(g_jack_client);
 172 }
 173
 174 void handle_midi(uint8_t* midiBuff, MidiSettings* settings)
 175 {
 176    if (midiBuff[0] == 0xF0 && midiBuff[1] == 0x7F && midiBuff[3] == 0x06)
 177    {
 178       const uint8_t messageDeviceID = midiBuff[2];
 179       if (messageDeviceID == settings->deviceID)
 180       {
 181          const char mmcCommand = midiBuff[4];
 182          switch (mmcCommand)
 183          {
 184             case 1:                 /* stop */
 185                if (settings->verbose)
 186                   printMMCMessage("MMC Stop -> JACK transport stop\n");
 187                jack_transport_stop(g_jack_client);
 188                break;
 189             case 2:                 /* play */
 190             case 3:                 /* deferred play */
 191                if (settings->verbose)
 192                   printMMCMessage("MMC Play -> JACK transport start\n");
 193                jack_transport_start(g_jack_client);
 194                break;
 195             case 4:
 196                if (settings->verbose)
 197                   printMMCMessage("MMC Fast Forward -> Ignored\n");
 198                break;
 199             case 5:                 /* rewind */
 200                if (settings->verbose)
 201                   printMMCMessage("MMC Play -> JACK transport locate to 0\n");
 202                jack_transport_locate(g_jack_client, 0);
 203                break;
 204             case 6:
 205                if (settings->verbose)
 206                   printMMCMessage("MMC Record Strobe (Punch In) -> Ignored\n");
 207                break;
 208             case 7:
 209                if (settings->verbose)
 210                   printMMCMessage("MMC Record Exit (Punch out) -> Ignored\n");
 211                break;
 212             case 8:
 213                if (settings->verbose)
 214                   printMMCMessage("MMC Record Ready (Record Pause) -> Ignored\n");
 215                break;
 216             case 9:                 /* pause */
 217                if (settings->verbose)
 218                   printMMCMessage("MMC Pause -> JACK transport stop\n");
 219                jack_transport_stop(g_jack_client);
 220                break;
 221             case 0x44:              /* goto */
 222                if (midiBuff[5] == 0x06 && midiBuff[6] == 0x01)
 223                {
 224                   // some devices call hour 0 "60". Mask off the upper bits
 225                   uint8_t hour = (midiBuff[7] & 0x1f);
 226                   uint8_t minute = midiBuff[8];
 227                   uint8_t second = midiBuff[9];
 228                   uint8_t frame = midiBuff[10];
 229                   uint8_t subframe = midiBuff[11]; // percentage of a frame: 0 - 99
 230                   jack_position_t jack_pos;
 231
 232                   // get Jack's current framerate and position
 233                   jack_transport_query(g_jack_client, &jack_pos);
 234                   uint32_t jack_frame_rate = jack_pos.frame_rate;
 235                   uint32_t jack_time_ms = (jack_pos.frame * 1000) / jack_frame_rate;
 236                   uint32_t device_time_ms = ((subframe * 10) / settings->frameRate + // subframe == 1/100th of a frame
 237                         (frame * 1000) / settings->frameRate +
 238                         (second * 1000) +
 239                         (minute * 60 * 1000) +
 240                         (hour * 60 * 60 * 1000));
 241
 242                   // difference in milliseconds from JACK's reported transport to the MIDI goto's time
 243                   uint32_t jitter = (device_time_ms > jack_time_ms ? (device_time_ms - jack_time_ms) : (jack_time_ms - device_time_ms));
 244
 245                   if (settings->verbose)
 246                      printMMCMessage("MMC goto hour: %d, min: %d, sec: %d, frame: %d, subframe: %d\n",
 247                            hour,
 248                            minute,
 249                            second,
 250                            frame,
 251                            subframe);
 252
 253                   // check if the JACK clock is far enough away from the MMC time to care
 254                   if (jitter > settings->jitterTolerance)
 255                   {  // it is, change it.
 256                      jack_pos.valid = 0; // only the frame number will be valid since that's all we're changing
 257
 258                      // need a placeholder so that we can keep precision while not letting the integer overflow
 259                      uint64_t placeholder =  (uint64_t)device_time_ms * jack_frame_rate / 1000;
 260                      jack_pos.frame = placeholder;
 261
 262                      jack_transport_reposition(g_jack_client, &jack_pos);
 263                   }
 264                   else if (settings->verbose)
 265                      printMMCMessage("New position is within jitter range, ignoring. (%d ms)\n", jitter);
 266                }
 267                break;
 268             case 0x48:              /* step */
 269                {
 270                   int step;
 271                   jack_position_t jack_pos;
 272
 273                   step = midiBuff[6];
 274                   if (step > 0x40)
 275                   {
 276                      step &= 0x3F;
 277                      step = -step;
 278                   }
 279
 280                   if (settings->verbose)
 281                      printMMCMessage("MMC Step %d\n", step);
 282
 283                   // get Jack's current framerate and position
 284                   jack_transport_query(g_jack_client, &jack_pos);
 285
 286                   jack_pos.valid = 0; // only the frame number will be valid since that's all we're changing
 287
 288                   jack_pos.frame += (int64_t)step * (int64_t)jack_pos.frame_rate / (int64_t)10;
 289
 290                   jack_transport_reposition(g_jack_client, &jack_pos);
 291                }
 292                break;
 293             default:
 294                if (settings->verbose)
 295                   printMMCMessage("unsupported MMC command: 0x%x\n", mmcCommand);
 296          }
 297       }
 298       else if (settings->verbose)
 299       {
 300          printMMCMessage("MMC command received for device ID %x while listening for commands from device ID %x. Have you specified the correct device ID to listen to?\n",
 301                 messageDeviceID,
 302                 settings->deviceID);
 303
 304       }
 305    }
 306 }
 307
 308 uint8_t* get_midi_input ()
 309 {
 310    snd_seq_event_t * seq_event_ptr = NULL;
 311
 312 #if LASH_SUPPORT
 313    /* Process LASH events */
 314    {
 315       lash_event_t * lash_event_ptr = NULL;
 316       lash_config_t * lash_config_ptr = NULL;
 317       while ((lash_event_ptr = lash_get_event(g_lashc)) != NULL)
 318       {
 319          process_lash_event(lash_event_ptr);
 320          lash_event_destroy(lash_event_ptr);
 321       }
 322
 323       /* Process LASH configs */
 324       while ((lash_config_ptr = lash_get_config(g_lashc)) != NULL)
 325       {
 326          process_lash_config(lash_config_ptr);
 327          lash_config_destroy(lash_config_ptr);
 328       }
 329    }
 330 #endif
 331
 332    if (poll(g_pollDescriptor, g_numDescriptors, 250) > 0 && snd_seq_event_input(g_seq_ptr, &seq_event_ptr) >= 0 && seq_event_ptr->type == SND_SEQ_EVENT_SYSEX)
 333       return ((uint8_t *)seq_event_ptr->data.ext.ptr);
 334
 335    return 0;
 336 }
 337
 338 void cleanup_globals()
 339 {
 340    int ret = 0;
 341
 342    if (g_jack_client)
 343    {
 344 #if JACK_MIDI_SUPPORT
 345       jack_port_unregister(g_jack_client, g_jackMidiIn);
 346 #endif
 347       jack_deactivate(g_jack_client);
 348       jack_client_close(g_jack_client);
 349    }
 350
 351    if (g_seq_ptr)
 352    {
 353       ret = snd_seq_close(g_seq_ptr);
 354       if (ret < 0)
 355       {
 356          printMMCMessage("Cannot close sequncer, %s\n", snd_strerror(ret));
 357       }
 358    }
 359
 360    if (g_pollDescriptor)
 361       free(g_pollDescriptor);
 362 }