libs/ardour/session_process.cc

   1 /*
   2     Copyright (C) 1999-2002 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <cmath>
  21 #include <cerrno>
  22 #include <algorithm>
  23 #include <unistd.h>
  24
  25 #include "pbd/error.h"
  26 #include "pbd/enumwriter.h"
  27
  28 #include <glibmm/threads.h>
  29
  30 #include "ardour/audioengine.h"
  31 #include "ardour/auditioner.h"
  32 #include "ardour/butler.h"
  33 #include "ardour/cycle_timer.h"
  34 #include "ardour/debug.h"
  35 #include "ardour/disk_reader.h"
  36 #include "ardour/graph.h"
  37 #include "ardour/port.h"
  38 #include "ardour/process_thread.h"
  39 #include "ardour/scene_changer.h"
  40 #include "ardour/session.h"
  41 #include "ardour/slave.h"
  42 #include "ardour/ticker.h"
  43 #include "ardour/types.h"
  44 #include "ardour/vca.h"
  45 #include "ardour/vca_manager.h"
  46
  47 #include "midi++/mmc.h"
  48
  49 #include "pbd/i18n.h"
  50
  51 using namespace ARDOUR;
  52 using namespace PBD;
  53 using namespace std;
  54
  55 /** Called by the audio engine when there is work to be done with JACK.
  56  * @param nframes Number of samples to process.
  57  */
  58
  59 void
  60 Session::process (pframes_t nframes)
  61 {
  62         samplepos_t transport_at_start = _transport_sample;
  63
  64         _silent = false;
  65
  66         if (processing_blocked()) {
  67                 _silent = true;
  68                 return;
  69         }
  70
  71         if (non_realtime_work_pending()) {
  72                 if (!_butler->transport_work_requested ()) {
  73                         post_transport ();
  74                 }
  75         }
  76
  77         _engine.main_thread()->get_buffers ();
  78
  79         (this->*process_function) (nframes);
  80
  81         /* realtime-safe meter-position and processor-order changes
  82          *
  83          * ideally this would be done in
  84          * Route::process_output_buffers() but various functions
  85          * callig it hold a _processor_lock reader-lock
  86          */
  87         boost::shared_ptr<RouteList> r = routes.reader ();
  88         for (RouteList::const_iterator i = r->begin(); i != r->end(); ++i) {
  89                 if ((*i)->apply_processor_changes_rt()) {
  90                         _rt_emit_pending = true;
  91                 }
  92         }
  93         if (_rt_emit_pending) {
  94                 if (!_rt_thread_active) {
  95                         emit_route_signals ();
  96                 }
  97                 if (pthread_mutex_trylock (&_rt_emit_mutex) == 0) {
  98                         pthread_cond_signal (&_rt_emit_cond);
  99                         pthread_mutex_unlock (&_rt_emit_mutex);
 100                         _rt_emit_pending = false;
 101                 }
 102         }
 103
 104         _engine.main_thread()->drop_buffers ();
 105
 106         /* deliver MIDI clock. Note that we need to use the transport sample
 107          * position at the start of process(), not the value at the end of
 108          * it. We may already have ticked() because of a transport state
 109          * change, for example.
 110          */
 111
 112         try {
 113                 if (!_silent && !_engine.freewheeling() && Config->get_send_midi_clock() && (transport_speed() == 1.0f || transport_speed() == 0.0f) && midi_clock->has_midi_port()) {
 114                         midi_clock->tick (transport_at_start, nframes);
 115                 }
 116
 117                 _scene_changer->run (transport_at_start, transport_at_start + nframes);
 118
 119         } catch (...) {
 120                 /* don't bother with a message */
 121         }
 122
 123         SendFeedback (); /* EMIT SIGNAL */
 124 }
 125
 126 int
 127 Session::fail_roll (pframes_t nframes)
 128 {
 129         return no_roll (nframes);
 130 }
 131
 132 int
 133 Session::no_roll (pframes_t nframes)
 134 {
 135         PT_TIMING_CHECK (4);
 136
 137         samplepos_t end_sample = _transport_sample + nframes; // FIXME: varispeed + no_roll ??
 138         int ret = 0;
 139         boost::shared_ptr<RouteList> r = routes.reader ();
 140
 141         if (_click_io) {
 142                 _click_io->silence (nframes);
 143         }
 144
 145         ltc_tx_send_time_code_for_cycle (_transport_sample, end_sample, _target_transport_speed, _transport_speed, nframes);
 146
 147         VCAList v = _vca_manager->vcas ();
 148         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 149                 (*i)->automation_run (_transport_sample, nframes);
 150         }
 151
 152         if (_process_graph) {
 153                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 154                 _process_graph->routes_no_roll( nframes, _transport_sample, end_sample, non_realtime_work_pending());
 155         } else {
 156                 PT_TIMING_CHECK (10);
 157                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 158
 159                         if ((*i)->is_auditioner()) {
 160                                 continue;
 161                         }
 162
 163                         if ((*i)->no_roll (nframes, _transport_sample, end_sample, non_realtime_work_pending())) {
 164                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 165                                 ret = -1;
 166                                 break;
 167                         }
 168                 }
 169                 PT_TIMING_CHECK (11);
 170         }
 171
 172         PT_TIMING_CHECK (5);
 173         return ret;
 174 }
 175
 176 /** @param need_butler to be set to true by this method if it needs the butler,
 177  *  otherwise it must be left alone.
 178  */
 179 int
 180 Session::process_routes (pframes_t nframes, bool& need_butler)
 181 {
 182         boost::shared_ptr<RouteList> r = routes.reader ();
 183
 184         const samplepos_t start_sample = _transport_sample;
 185         const samplepos_t end_sample = _transport_sample + floor (nframes * _transport_speed);
 186
 187         VCAList v = _vca_manager->vcas ();
 188         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 189                 (*i)->automation_run (start_sample, nframes);
 190         }
 191
 192         _global_locate_pending = locate_pending ();
 193
 194         if (_process_graph) {
 195                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 196                 if (_process_graph->process_routes (nframes, start_sample, end_sample, need_butler) < 0) {
 197                         stop_transport ();
 198                         return -1;
 199                 }
 200         } else {
 201
 202                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 203
 204                         int ret;
 205
 206                         if ((*i)->is_auditioner()) {
 207                                 continue;
 208                         }
 209
 210                         bool b = false;
 211
 212                         if ((ret = (*i)->roll (nframes, start_sample, end_sample, b)) < 0) {
 213                                 stop_transport ();
 214                                 return -1;
 215                         }
 216
 217                         if (b) {
 218                                 DEBUG_TRACE (DEBUG::Butler, string_compose ("%1 rolled and needs butler\n", (*i)->name()));
 219                                 need_butler = true;
 220                         }
 221                 }
 222         }
 223
 224         return 0;
 225 }
 226
 227 void
 228 Session::get_track_statistics ()
 229 {
 230         float pworst = 1.0f;
 231         float cworst = 1.0f;
 232
 233         boost::shared_ptr<RouteList> rl = routes.reader();
 234         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 235
 236                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 237
 238                 if (!tr || tr->is_private_route()) {
 239                         continue;
 240                 }
 241
 242                 pworst = min (pworst, tr->playback_buffer_load());
 243                 cworst = min (cworst, tr->capture_buffer_load());
 244         }
 245
 246         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 247         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 248
 249         if (actively_recording()) {
 250                 set_dirty();
 251         }
 252 }
 253
 254 /** Process callback used when the auditioner is not active */
 255 void
 256 Session::process_with_events (pframes_t nframes)
 257 {
 258         PT_TIMING_CHECK (3);
 259
 260         SessionEvent*  ev;
 261         pframes_t      this_nframes;
 262         samplepos_t     end_sample;
 263         bool           session_needs_butler = false;
 264         samplecnt_t     samples_moved;
 265
 266         /* make sure the auditioner is silent */
 267
 268         if (auditioner) {
 269                 auditioner->silence (nframes);
 270         }
 271
 272         /* handle any pending events */
 273
 274         while (pending_events.read (&ev, 1) == 1) {
 275                 merge_event (ev);
 276         }
 277
 278         /* if we are not in the middle of a state change,
 279            and there are immediate events queued up,
 280            process them.
 281         */
 282
 283         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 284                 SessionEvent *ev = immediate_events.front ();
 285                 immediate_events.pop_front ();
 286                 process_event (ev);
 287         }
 288
 289         /* only count-in when going to roll at speed 1.0 */
 290         if (_transport_speed != 1.0 && _count_in_samples > 0) {
 291                 _count_in_samples = 0;
 292         }
 293         if (_transport_speed == 0.0) {
 294                 _remaining_latency_preroll = 0;
 295         }
 296
 297         assert (_count_in_samples == 0 || _remaining_latency_preroll == 0 || _count_in_samples == _remaining_latency_preroll);
 298
 299         while (_count_in_samples > 0 || _remaining_latency_preroll > 0) {
 300                 samplecnt_t ns;
 301
 302                 if (_remaining_latency_preroll > 0) {
 303                         ns = std::min ((samplecnt_t)nframes, _remaining_latency_preroll);
 304                 } else {
 305                         ns = std::min ((samplecnt_t)nframes, _count_in_samples);
 306                 }
 307
 308                 boost::shared_ptr<RouteList> r = routes.reader ();
 309                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 310                         samplecnt_t route_offset = (*i)->playback_latency ();
 311                         if (_remaining_latency_preroll > route_offset + ns) {
 312                                 /* route will no-roll for complete pre-roll cycle */
 313                                 continue;
 314                         }
 315                         if (_remaining_latency_preroll > route_offset) {
 316                                 /* route may need partial no-roll and partial roll from
 317                                 * (_transport_sample - _remaining_latency_preroll) ..  +ns.
 318                                 * shorten and split the cycle.
 319                                 */
 320                                 ns = std::min (ns, (_remaining_latency_preroll - route_offset));
 321                         }
 322                 }
 323
 324                 if (_count_in_samples > 0) {
 325                         run_click (_transport_sample - _count_in_samples, ns);
 326                         assert (_count_in_samples >= ns);
 327                         _count_in_samples -= ns;
 328                 }
 329
 330                 if (_remaining_latency_preroll > 0) {
 331                         if (_count_in_samples == 0) {
 332                                 click (_transport_sample - _remaining_latency_preroll, ns);
 333                         }
 334                         if (process_routes (ns, session_needs_butler)) {
 335                                 fail_roll (ns);
 336                         }
 337                 } else {
 338                         no_roll (ns);
 339                 }
 340
 341                 if (_remaining_latency_preroll > 0) {
 342                         assert (_remaining_latency_preroll >= ns);
 343                         _remaining_latency_preroll -= ns;
 344                 }
 345
 346                 nframes -= ns;
 347
 348                 /* process events.. */
 349                 if (!events.empty() && next_event != events.end()) {
 350                         SessionEvent* this_event = *next_event;
 351                         Events::iterator the_next_one = next_event;
 352                         ++the_next_one;
 353
 354                         while (this_event && this_event->action_sample == _transport_sample) {
 355                                 process_event (this_event);
 356                                 if (the_next_one == events.end()) {
 357                                         this_event = 0;
 358                                 } else {
 359                                         this_event = *the_next_one;
 360                                         ++the_next_one;
 361                                 }
 362                         }
 363                         set_next_event ();
 364                 }
 365
 366                 if (nframes == 0) {
 367                         return;
 368                 } else {
 369                         _engine.split_cycle (ns);
 370                 }
 371         }
 372
 373         /* Decide on what to do with quarter-frame MTC during this cycle */
 374
 375         bool const was_sending_qf_mtc = _send_qf_mtc;
 376         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 377
 378         if (_transport_speed != 0) {
 379                 _send_qf_mtc = (
 380                         Config->get_send_mtc () &&
 381                         _transport_speed >= (1 - tolerance) &&
 382                         _transport_speed <= (1 + tolerance)
 383                         );
 384
 385                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 386                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 387                         _send_timecode_update = true;
 388                 }
 389
 390                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (sample_rate () / 4)) {
 391                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 392                            a quarter of a second since we sent anything at all, so send a full MTC update
 393                            this cycle.
 394                         */
 395                         _send_timecode_update = true;
 396                 }
 397
 398                 _pframes_since_last_mtc += nframes;
 399         }
 400
 401         /* Events caused a transport change (or we re-started sending
 402          * MTC), so send an MTC Full Frame (Timecode) message.  This
 403          * is sent whether rolling or not, to give slaves an idea of
 404          * ardour time on locates (and allow slow slaves to position
 405          * and prepare for rolling)
 406          */
 407         if (_send_timecode_update) {
 408                 send_full_time_code (_transport_sample, nframes);
 409         }
 410
 411         if (!process_can_proceed()) {
 412                 _silent = true;
 413                 return;
 414         }
 415
 416         if (events.empty() || next_event == events.end()) {
 417                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 418                 /* lua scripts may inject events */
 419                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 420                         merge_event (ev);
 421                 }
 422                 if (events.empty() || next_event == events.end()) {
 423                         process_without_events (nframes);
 424                         return;
 425                 }
 426         }
 427
 428         assert (_transport_speed == 0 || _transport_speed == 1.0 || _transport_speed == -1.0);
 429
 430         samples_moved = (samplecnt_t) nframes * _transport_speed;
 431
 432         end_sample = _transport_sample + samples_moved;
 433
 434         {
 435                 SessionEvent* this_event;
 436                 Events::iterator the_next_one;
 437
 438                 if (!process_can_proceed()) {
 439                         _silent = true;
 440                         return;
 441                 }
 442
 443                 if (!_exporting && _slave) {
 444                         if (!follow_slave (nframes)) {
 445                                 return;
 446                         }
 447                 }
 448
 449                 if (_transport_speed == 0) {
 450                         no_roll (nframes);
 451                         return;
 452                 }
 453
 454                 if (!_exporting && !timecode_transmission_suspended()) {
 455                         send_midi_time_code_for_cycle (_transport_sample, end_sample, nframes);
 456                 }
 457
 458                 ltc_tx_send_time_code_for_cycle (_transport_sample, end_sample, _target_transport_speed, _transport_speed, nframes);
 459
 460                 samplepos_t stop_limit = compute_stop_limit ();
 461
 462                 if (maybe_stop (stop_limit)) {
 463                         no_roll (nframes);
 464                         return;
 465                 }
 466
 467                 this_event = *next_event;
 468                 the_next_one = next_event;
 469                 ++the_next_one;
 470
 471                 /* yes folks, here it is, the actual loop where we really truly
 472                    process some audio
 473                 */
 474
 475                 while (nframes) {
 476
 477                         this_nframes = nframes; /* real (jack) time relative */
 478                         samples_moved = (samplecnt_t) floor (_transport_speed * nframes); /* transport relative */
 479
 480                         /* running an event, position transport precisely to its time */
 481                         if (this_event && this_event->action_sample <= end_sample && this_event->action_sample >= _transport_sample) {
 482                                 /* this isn't quite right for reverse play */
 483                                 samples_moved = (samplecnt_t) (this_event->action_sample - _transport_sample);
 484                                 this_nframes = abs (floor(samples_moved / _transport_speed));
 485                         }
 486
 487                         try_run_lua (this_nframes);
 488
 489                         if (this_nframes) {
 490
 491                                 click (_transport_sample, this_nframes);
 492
 493                                 if (process_routes (this_nframes, session_needs_butler)) {
 494                                         fail_roll (nframes);
 495                                         return;
 496                                 }
 497
 498                                 get_track_statistics ();
 499
 500                                 nframes -= this_nframes;
 501
 502                                 if (samples_moved < 0) {
 503                                         decrement_transport_position (-samples_moved);
 504                                 } else if (samples_moved) {
 505                                         increment_transport_position (samples_moved);
 506                                 }
 507
 508                                 maybe_stop (stop_limit);
 509                         }
 510
 511                         if (nframes > 0) {
 512                                 _engine.split_cycle (this_nframes);
 513                         }
 514
 515                         /* now handle this event and all others scheduled for the same time */
 516
 517                         while (this_event && this_event->action_sample == _transport_sample) {
 518                                 process_event (this_event);
 519
 520                                 if (the_next_one == events.end()) {
 521                                         this_event = 0;
 522                                 } else {
 523                                         this_event = *the_next_one;
 524                                         ++the_next_one;
 525                                 }
 526                         }
 527
 528                         /* if an event left our state changing, do the right thing */
 529
 530                         if (nframes && non_realtime_work_pending()) {
 531                                 no_roll (nframes);
 532                                 break;
 533                         }
 534
 535                         /* this is necessary to handle the case of seamless looping */
 536                         end_sample = _transport_sample + floor (nframes * _transport_speed);
 537                 }
 538
 539                 set_next_event ();
 540
 541         } /* implicit release of route lock */
 542
 543         if (session_needs_butler) {
 544                 DEBUG_TRACE (DEBUG::Butler, "p-with-events: session needs butler, call it\n");
 545                 _butler->summon ();
 546         }
 547 }
 548
 549 void
 550 Session::reset_slave_state ()
 551 {
 552         average_slave_delta = 1800;
 553         delta_accumulator_cnt = 0;
 554         have_first_delta_accumulator = false;
 555         _slave_state = Stopped;
 556         DiskReader::set_no_disk_output (false);
 557 }
 558
 559 bool
 560 Session::transport_locked () const
 561 {
 562         Slave* sl = _slave;
 563
 564         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 565                 return true;
 566         }
 567
 568         return false;
 569 }
 570
 571 bool
 572 Session::follow_slave (pframes_t nframes)
 573 {
 574         double slave_speed;
 575         samplepos_t slave_transport_sample;
 576         samplecnt_t this_delta;
 577         int dir;
 578
 579         if (!_slave->ok()) {
 580                 stop_transport ();
 581                 config.set_external_sync (false);
 582                 goto noroll;
 583         }
 584
 585         _slave->speed_and_position (slave_speed, slave_transport_sample);
 586
 587         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_sample, slave_speed));
 588
 589         if (!_slave->locked()) {
 590                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 591                 goto noroll;
 592         }
 593
 594         if (slave_transport_sample > _transport_sample) {
 595                 this_delta = slave_transport_sample - _transport_sample;
 596                 dir = 1;
 597         } else {
 598                 this_delta = _transport_sample - slave_transport_sample;
 599                 dir = -1;
 600         }
 601
 602         if (_slave->starting()) {
 603                 slave_speed = 0.0f;
 604         }
 605
 606         if (_slave->is_always_synced() ||
 607                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 608                         ) {
 609
 610                 /* if the TC source is synced, then we assume that its
 611                    speed is binary: 0.0 or 1.0
 612                 */
 613
 614                 if (slave_speed != 0.0f) {
 615                         slave_speed = 1.0f;
 616                 }
 617
 618         } else {
 619
 620                 /* if we are chasing and the average delta between us and the
 621                    master gets too big, we want to switch to silent
 622                    motion. so keep track of that here.
 623                 */
 624
 625                 if (_slave_state == Running) {
 626                         calculate_moving_average_of_slave_delta(dir, abs(this_delta));
 627                 }
 628         }
 629
 630         track_slave_state (slave_speed, slave_transport_sample, this_delta);
 631
 632         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 633                                                    _slave_state, slave_transport_sample, slave_speed, this_delta, average_slave_delta));
 634
 635
 636         if (_slave_state == Running && !_slave->is_always_synced() && !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)) {
 637
 638                 /* may need to varispeed to sync with slave */
 639
 640                 if (_transport_speed != 0.0f) {
 641
 642                         /*
 643                            note that average_dir is +1 or -1
 644                         */
 645
 646                         float delta;
 647
 648                         if (average_slave_delta == 0) {
 649                                 delta = this_delta;
 650                                 delta *= dir;
 651                         } else {
 652                                 delta = average_slave_delta;
 653                                 delta *= average_dir;
 654                         }
 655
 656 #ifndef NDEBUG
 657                         if (slave_speed != 0.0) {
 658                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 659                                                                            (int) (dir * this_delta),
 660                                                                            slave_speed,
 661                                                                            _transport_speed,
 662                                                                            _transport_sample,
 663                                                                            slave_transport_sample,
 664                                                                            average_slave_delta));
 665                         }
 666 #endif
 667
 668                         if (_slave->give_slave_full_control_over_transport_speed()) {
 669                                 set_transport_speed (slave_speed, 0, false, false);
 670                                 //std::cout << "set speed = " << slave_speed << "\n";
 671                         } else {
 672                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_sample_rate)));
 673                                 request_transport_speed (adjusted_speed);
 674                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 675                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 676                                                                            slave_speed));
 677                         }
 678
 679                         if (!actively_recording() && (samplecnt_t) average_slave_delta > _slave->resolution()) {
 680                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("average slave delta %1 greater than slave resolution %2 => no disk output\n", average_slave_delta, _slave->resolution()));
 681                                 /* run routes as normal, but no disk output */
 682                                 DiskReader::set_no_disk_output (true);
 683                                 return true;
 684                         }
 685
 686                         if (!have_first_delta_accumulator) {
 687                                 DEBUG_TRACE (DEBUG::Slave, "waiting for first slave delta accumulator to be ready, no disk output\n");
 688                                 /* run routes as normal, but no disk output */
 689                                 DiskReader::set_no_disk_output (true);
 690                                 return true;
 691                         }
 692                 }
 693         }
 694
 695
 696         if (!have_first_delta_accumulator) {
 697                 DEBUG_TRACE (DEBUG::Slave, "still waiting to compute slave delta, no disk output\n");
 698                 DiskReader::set_no_disk_output (true);
 699         } else {
 700                 DiskReader::set_no_disk_output (false);
 701         }
 702
 703         if ((_slave_state == Running) && (0 == (post_transport_work () & ~PostTransportSpeed))) {
 704                 /* speed is set, we're locked, and good to go */
 705                 return true;
 706         }
 707
 708   noroll:
 709         /* don't move at all */
 710         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 711         no_roll (nframes);
 712         return false;
 713 }
 714
 715 void
 716 Session::calculate_moving_average_of_slave_delta (int dir, samplecnt_t this_delta)
 717 {
 718         if (delta_accumulator_cnt >= delta_accumulator_size) {
 719                 have_first_delta_accumulator = true;
 720                 delta_accumulator_cnt = 0;
 721         }
 722
 723         if (delta_accumulator_cnt != 0 || this_delta < _current_sample_rate) {
 724                 delta_accumulator[delta_accumulator_cnt++] = (samplecnt_t) dir *  (samplecnt_t) this_delta;
 725         }
 726
 727         if (have_first_delta_accumulator) {
 728                 average_slave_delta = 0L;
 729                 for (int i = 0; i < delta_accumulator_size; ++i) {
 730                         average_slave_delta += delta_accumulator[i];
 731                 }
 732                 average_slave_delta /= (int32_t) delta_accumulator_size;
 733                 if (average_slave_delta < 0L) {
 734                         average_dir = -1;
 735                         average_slave_delta = average_slave_delta;
 736                 } else {
 737                         average_dir = 1;
 738                 }
 739         }
 740 }
 741
 742 void
 743 Session::track_slave_state (float slave_speed, samplepos_t slave_transport_sample, samplecnt_t /*this_delta*/)
 744 {
 745         if (slave_speed != 0.0f) {
 746
 747                 /* slave is running */
 748
 749                 switch (_slave_state) {
 750                 case Stopped:
 751                         if (_slave->requires_seekahead()) {
 752                                 slave_wait_end = slave_transport_sample + _slave->seekahead_distance ();
 753                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 754                                 /* we can call locate() here because we are in process context */
 755                                 locate (slave_wait_end, false, false);
 756                                 _slave_state = Waiting;
 757
 758                         } else {
 759
 760                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_sample));
 761
 762                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 763                                 average_slave_delta = 0L;
 764
 765                                 Location* al = _locations->auto_loop_location();
 766
 767                                 if (al && play_loop && (slave_transport_sample < al->start() || slave_transport_sample > al->end())) {
 768                                         // cancel looping
 769                                         request_play_loop(false);
 770                                 }
 771
 772                                 if (slave_transport_sample != _transport_sample) {
 773                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_sample, slave_transport_sample));
 774                                         locate (slave_transport_sample, false, false);
 775                                 }
 776                                 _slave_state = Running;
 777                         }
 778                         break;
 779
 780                 case Waiting:
 781                 default:
 782                         break;
 783                 }
 784
 785                 if (_slave_state == Waiting) {
 786
 787                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_sample));
 788
 789                         if (slave_transport_sample >= slave_wait_end) {
 790
 791                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_sample, _transport_sample));
 792
 793                                 _slave_state = Running;
 794
 795                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 796                                    precisely with the master.
 797                                 */
 798
 799
 800                                 bool ok = true;
 801                                 samplecnt_t sample_delta = slave_transport_sample - _transport_sample;
 802
 803                                 boost::shared_ptr<RouteList> rl = routes.reader();
 804                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 805                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 806                                         if (tr && !tr->can_internal_playback_seek (sample_delta)) {
 807                                                 ok = false;
 808                                                 break;
 809                                         }
 810                                 }
 811
 812                                 if (ok) {
 813                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 814                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 815                                                 if (tr) {
 816                                                         tr->internal_playback_seek (sample_delta);
 817                                                 }
 818                                         }
 819                                         _transport_sample += sample_delta;
 820
 821                                 } else {
 822                                         cerr << "cannot micro-seek\n";
 823                                         /* XXX what? */
 824                                 }
 825                         }
 826                 }
 827
 828                 if (_slave_state == Running && _transport_speed == 0.0f) {
 829                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 830                         start_transport ();
 831                 }
 832
 833         } else { // slave_speed is 0
 834
 835                 /* slave has stopped */
 836
 837                 if (_transport_speed != 0.0f) {
 838                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 sample %2 tf %3\n", slave_speed, slave_transport_sample, _transport_sample));
 839                         stop_transport ();
 840                 }
 841
 842                 if (slave_transport_sample != _transport_sample) {
 843                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_sample));
 844                         force_locate (slave_transport_sample, false);
 845                 }
 846
 847                 reset_slave_state();
 848         }
 849 }
 850
 851 void
 852 Session::process_without_events (pframes_t nframes)
 853 {
 854         bool session_needs_butler = false;
 855         samplecnt_t samples_moved;
 856
 857         if (!process_can_proceed()) {
 858                 _silent = true;
 859                 return;
 860         }
 861
 862         if (!_exporting && _slave) {
 863                 if (!follow_slave (nframes)) {
 864                         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample, 0, 0 , nframes);
 865                         return;
 866                 }
 867         }
 868
 869         if (_transport_speed == 0) {
 870                 no_roll (nframes);
 871                 return;
 872         }
 873
 874         assert (_transport_speed == 1.f || _transport_speed == -1.f);
 875         samples_moved = (samplecnt_t) nframes * _transport_speed;
 876
 877         if (!_exporting && !timecode_transmission_suspended()) {
 878                 send_midi_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, nframes);
 879         }
 880
 881         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, _target_transport_speed, _transport_speed, nframes);
 882
 883         samplepos_t const stop_limit = compute_stop_limit ();
 884
 885         if (maybe_stop (stop_limit)) {
 886                 no_roll (nframes);
 887                 return;
 888         }
 889
 890         if (maybe_sync_start (nframes)) {
 891                 return;
 892         }
 893
 894         click (_transport_sample, nframes);
 895
 896         if (process_routes (nframes, session_needs_butler)) {
 897                 fail_roll (nframes);
 898                 return;
 899         }
 900
 901         get_track_statistics ();
 902
 903         if (samples_moved < 0) {
 904                 decrement_transport_position (-samples_moved);
 905         } else if (samples_moved) {
 906                 increment_transport_position (samples_moved);
 907         }
 908
 909         maybe_stop (stop_limit);
 910
 911         if (session_needs_butler) {
 912                 DEBUG_TRACE (DEBUG::Butler, "p-without-events: session needs butler, call it\n");
 913                 _butler->summon ();
 914         }
 915 }
 916
 917 /** Process callback used when the auditioner is active.
 918  * @param nframes number of samples to process.
 919  */
 920 void
 921 Session::process_audition (pframes_t nframes)
 922 {
 923         SessionEvent* ev;
 924         boost::shared_ptr<RouteList> r = routes.reader ();
 925
 926         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 927                 if (!(*i)->is_auditioner()) {
 928                         (*i)->silence (nframes);
 929                 }
 930         }
 931
 932         /* run the auditioner, and if it says we need butler service, ask for it */
 933
 934         if (auditioner->play_audition (nframes) > 0) {
 935                 DEBUG_TRACE (DEBUG::Butler, "auditioner needs butler, call it\n");
 936                 _butler->summon ();
 937         }
 938
 939         /* if using a monitor section, run it because otherwise we don't hear anything */
 940
 941         if (_monitor_out && auditioner->needs_monitor()) {
 942                 _monitor_out->monitor_run (_transport_sample, _transport_sample + nframes, nframes);
 943         }
 944
 945         /* handle pending events */
 946
 947         while (pending_events.read (&ev, 1) == 1) {
 948                 merge_event (ev);
 949         }
 950
 951         /* if we are not in the middle of a state change,
 952            and there are immediate events queued up,
 953            process them.
 954         */
 955
 956         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 957                 SessionEvent *ev = immediate_events.front ();
 958                 immediate_events.pop_front ();
 959                 process_event (ev);
 960         }
 961
 962         if (!auditioner->auditioning()) {
 963                 /* auditioner no longer active, so go back to the normal process callback */
 964                 process_function = &Session::process_with_events;
 965         }
 966 }
 967
 968 bool
 969 Session::maybe_sync_start (pframes_t & nframes)
 970 {
 971         pframes_t sync_offset;
 972
 973         if (!waiting_for_sync_offset) {
 974                 return false;
 975         }
 976
 977         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 978
 979                 /* generate silence up to the sync point, then
 980                    adjust nframes + offset to reflect whatever
 981                    is left to do.
 982                 */
 983
 984                 no_roll (sync_offset);
 985                 nframes -= sync_offset;
 986                 Port::increment_global_port_buffer_offset (sync_offset);
 987                 waiting_for_sync_offset = false;
 988
 989                 if (nframes == 0) {
 990                         return true; // done, nothing left to process
 991                 }
 992
 993         } else {
 994
 995                 /* sync offset point is not within this process()
 996                    cycle, so just generate silence. and don't bother
 997                    with any fancy stuff here, just the minimal silence.
 998                 */
 999
1000                 _silent = true;
1001
1002                 if (Config->get_locate_while_waiting_for_sync()) {
1003                         if (micro_locate (nframes)) {
1004                                 /* XXX ERROR !!! XXX */
1005                         }
1006                 }
1007
1008                 return true; // done, nothing left to process
1009         }
1010
1011         return false;
1012 }
1013
1014 void
1015 Session::queue_event (SessionEvent* ev)
1016 {
1017         if (_state_of_the_state & Deletion) {
1018                 return;
1019         } else if (_state_of_the_state & Loading) {
1020                 merge_event (ev);
1021         } else {
1022                 Glib::Threads::Mutex::Lock lm (rb_write_lock);
1023                 pending_events.write (&ev, 1);
1024         }
1025 }
1026
1027 void
1028 Session::set_next_event ()
1029 {
1030         if (events.empty()) {
1031                 next_event = events.end();
1032                 return;
1033         }
1034
1035         if (next_event == events.end()) {
1036                 next_event = events.begin();
1037         }
1038
1039         if ((*next_event)->action_sample > _transport_sample) {
1040                 next_event = events.begin();
1041         }
1042
1043         for (; next_event != events.end(); ++next_event) {
1044                 if ((*next_event)->action_sample >= _transport_sample) {
1045                         break;
1046                 }
1047         }
1048 }
1049
1050 void
1051 Session::process_event (SessionEvent* ev)
1052 {
1053         bool remove = true;
1054         bool del = true;
1055
1056         /* if we're in the middle of a state change (i.e. waiting
1057            for the butler thread to complete the non-realtime
1058            part of the change), we'll just have to queue this
1059            event for a time when the change is complete.
1060         */
1061
1062         if (non_realtime_work_pending()) {
1063
1064                 /* except locates, which we have the capability to handle */
1065
1066                 if (ev->type != SessionEvent::Locate) {
1067                         immediate_events.insert (immediate_events.end(), ev);
1068                         _remove_event (ev);
1069                         return;
1070                 }
1071         }
1072
1073         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_sample));
1074
1075         switch (ev->type) {
1076         case SessionEvent::SetLoop:
1077                 set_play_loop (ev->yes_or_no, ev->speed);
1078                 break;
1079
1080         case SessionEvent::AutoLoop:
1081                 if (play_loop) {
1082                         /* roll after locate, do not flush, set "with loop"
1083                            true only if we are seamless looping
1084                         */
1085                         start_locate (ev->target_sample, true, false, Config->get_seamless_loop());
1086                 }
1087                 remove = false;
1088                 del = false;
1089                 break;
1090
1091         case SessionEvent::Locate:
1092                 if (ev->yes_or_no) { /* force locate */
1093                         /* args: do not roll after locate, do flush, not with loop */
1094                         locate (ev->target_sample, false, true, false);
1095                 } else {
1096                         /* args: do not roll after locate, do flush, not with loop */
1097                         start_locate (ev->target_sample, false, true, false);
1098                 }
1099                 _send_timecode_update = true;
1100                 break;
1101
1102         case SessionEvent::LocateRoll:
1103                 if (ev->yes_or_no) {
1104                         /* args: roll after locate, do flush, not with loop */
1105                         locate (ev->target_sample, true, true, false);
1106                 } else {
1107                         /* args: roll after locate, do flush, not with loop */
1108                         start_locate (ev->target_sample, true, true, false);
1109                 }
1110                 _send_timecode_update = true;
1111                 break;
1112
1113         case SessionEvent::Skip:
1114                 if (Config->get_skip_playback()) {
1115                         start_locate (ev->target_sample, true, true, false);
1116                         _send_timecode_update = true;
1117                 }
1118                 remove = false;
1119                 del = false;
1120                 break;
1121
1122         case SessionEvent::LocateRollLocate:
1123                 // locate is handled by ::request_roll_at_and_return()
1124                 _requested_return_sample = ev->target_sample;
1125                 request_locate (ev->target2_sample, true);
1126                 break;
1127
1128
1129         case SessionEvent::SetTransportSpeed:
1130                 set_transport_speed (ev->speed, ev->target_sample, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1131                 break;
1132
1133         case SessionEvent::PunchIn:
1134                 // cerr << "PunchIN at " << transport_sample() << endl;
1135                 if (config.get_punch_in() && record_status() == Enabled) {
1136                         enable_record ();
1137                 }
1138                 remove = false;
1139                 del = false;
1140                 break;
1141
1142         case SessionEvent::PunchOut:
1143                 // cerr << "PunchOUT at " << transport_sample() << endl;
1144                 if (config.get_punch_out()) {
1145                         step_back_from_record ();
1146                 }
1147                 remove = false;
1148                 del = false;
1149                 break;
1150
1151         case SessionEvent::StopOnce:
1152                 if (!non_realtime_work_pending()) {
1153                         _clear_event_type (SessionEvent::StopOnce);
1154                         stop_transport (ev->yes_or_no);
1155                 }
1156                 remove = false;
1157                 del = false;
1158                 break;
1159
1160         case SessionEvent::RangeStop:
1161                 if (!non_realtime_work_pending()) {
1162                         stop_transport (ev->yes_or_no);
1163                 }
1164                 remove = false;
1165                 del = false;
1166                 break;
1167
1168         case SessionEvent::RangeLocate:
1169                 /* args: roll after locate, do flush, not with loop */
1170                 start_locate (ev->target_sample, true, true, false);
1171                 remove = false;
1172                 del = false;
1173                 break;
1174
1175         case SessionEvent::Overwrite:
1176                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1177                 break;
1178
1179         case SessionEvent::SetSyncSource:
1180                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1181                 use_sync_source (ev->slave);
1182                 break;
1183
1184         case SessionEvent::Audition:
1185                 set_audition (ev->region);
1186                 // drop reference to region
1187                 ev->region.reset ();
1188                 break;
1189
1190         case SessionEvent::SetPlayAudioRange:
1191                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1192                 break;
1193
1194         case SessionEvent::CancelPlayAudioRange:
1195                 unset_play_range();
1196                 break;
1197
1198         case SessionEvent::RealTimeOperation:
1199                 process_rtop (ev);
1200                 del = false; // other side of RT request needs to clean up
1201                 break;
1202
1203         case SessionEvent::AdjustPlaybackBuffering:
1204                 schedule_playback_buffering_adjustment ();
1205                 break;
1206
1207         case SessionEvent::AdjustCaptureBuffering:
1208                 schedule_capture_buffering_adjustment ();
1209                 break;
1210
1211         case SessionEvent::SetTimecodeTransmission:
1212                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1213                 break;
1214
1215         default:
1216           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1217                 abort(); /*NOTREACHED*/
1218                 break;
1219         };
1220
1221         if (remove) {
1222                 del = del && !_remove_event (ev);
1223         }
1224
1225         if (del) {
1226                 delete ev;
1227         }
1228 }
1229
1230 samplepos_t
1231 Session::compute_stop_limit () const
1232 {
1233         if (!Config->get_stop_at_session_end ()) {
1234                 return max_samplepos;
1235         }
1236
1237         if (_slave) {
1238                 return max_samplepos;
1239         }
1240
1241         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1242         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1243
1244         if (actively_recording ()) {
1245                 /* permanently recording */
1246                 return max_samplepos;
1247         } else if (punching_in && !punching_out) {
1248                 /* punching in but never out */
1249                 return max_samplepos;
1250         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_sample()) {
1251                 /* punching in and punching out after session end */
1252                 return max_samplepos;
1253         }
1254
1255         return current_end_sample ();
1256 }
1257
1258
1259
1260 /* dedicated thread for signal emission.
1261  *
1262  * while sending cross-thread signals from the process thread
1263  * is fine in general, PBD::Signal's use of boost::function and
1264  * boost:bind can produce a vast overhead which is not
1265  * acceptable for low latency.
1266  *
1267  * This works around the issue by moving the boost overhead
1268  * out of the RT thread. The overall load is probably higher but
1269  * the realtime thread remains unaffected.
1270  */
1271
1272 void
1273 Session::emit_route_signals ()
1274 {
1275         // TODO use RAII to allow using these signals in other places
1276         BatchUpdateStart(); /* EMIT SIGNAL */
1277         boost::shared_ptr<RouteList> r = routes.reader ();
1278         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1279                 (*ci)->emit_pending_signals ();
1280         }
1281         BatchUpdateEnd(); /* EMIT SIGNAL */
1282 }
1283
1284 void
1285 Session::emit_thread_start ()
1286 {
1287         if (_rt_thread_active) {
1288                 return;
1289         }
1290         _rt_thread_active = true;
1291
1292         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1293                 _rt_thread_active = false;
1294         }
1295 }
1296
1297 void
1298 Session::emit_thread_terminate ()
1299 {
1300         if (!_rt_thread_active) {
1301                 return;
1302         }
1303         _rt_thread_active = false;
1304
1305         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1306                 pthread_cond_signal (&_rt_emit_cond);
1307                 pthread_mutex_unlock (&_rt_emit_mutex);
1308         }
1309
1310         void *status;
1311         pthread_join (_rt_emit_thread, &status);
1312 }
1313
1314 void *
1315 Session::emit_thread (void *arg)
1316 {
1317         Session *s = static_cast<Session *>(arg);
1318         s->emit_thread_run ();
1319         pthread_exit (0);
1320         return 0;
1321 }
1322
1323 void
1324 Session::emit_thread_run ()
1325 {
1326         pthread_mutex_lock (&_rt_emit_mutex);
1327         while (_rt_thread_active) {
1328                 emit_route_signals();
1329                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1330         }
1331         pthread_mutex_unlock (&_rt_emit_mutex);
1332 }