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         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 140         boost::shared_ptr<RouteList> r = routes.reader ();
 141
 142         if (_click_io) {
 143                 _click_io->silence (nframes);
 144         }
 145
 146         ltc_tx_send_time_code_for_cycle (_transport_sample, end_sample, _target_transport_speed, _transport_speed, nframes);
 147
 148         VCAList v = _vca_manager->vcas ();
 149         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 150                 (*i)->automation_run (_transport_sample, nframes);
 151         }
 152
 153         if (_process_graph) {
 154                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 155                 _process_graph->routes_no_roll( nframes, _transport_sample, end_sample, non_realtime_work_pending(), declick);
 156         } else {
 157                 PT_TIMING_CHECK (10);
 158                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 159
 160                         if ((*i)->is_auditioner()) {
 161                                 continue;
 162                         }
 163
 164                         (*i)->set_pending_declick (declick);
 165
 166                         if ((*i)->no_roll (nframes, _transport_sample, end_sample, non_realtime_work_pending())) {
 167                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 168                                 ret = -1;
 169                                 break;
 170                         }
 171                 }
 172                 PT_TIMING_CHECK (11);
 173         }
 174
 175         PT_TIMING_CHECK (5);
 176         return ret;
 177 }
 178
 179 /** @param need_butler to be set to true by this method if it needs the butler,
 180  *  otherwise it must be left alone.
 181  */
 182 int
 183 Session::process_routes (pframes_t nframes, bool& need_butler)
 184 {
 185         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 186         boost::shared_ptr<RouteList> r = routes.reader ();
 187
 188         const samplepos_t start_sample = _transport_sample;
 189         const samplepos_t end_sample = _transport_sample + floor (nframes * _transport_speed);
 190
 191         VCAList v = _vca_manager->vcas ();
 192         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 193                 (*i)->automation_run (start_sample, nframes);
 194         }
 195
 196         _global_locate_pending = locate_pending ();
 197
 198         if (_process_graph) {
 199                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 200                 if (_process_graph->process_routes (nframes, start_sample, end_sample, declick, need_butler) < 0) {
 201                         stop_transport ();
 202                         return -1;
 203                 }
 204         } else {
 205
 206                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 207
 208                         int ret;
 209
 210                         if ((*i)->is_auditioner()) {
 211                                 continue;
 212                         }
 213
 214                         (*i)->set_pending_declick (declick);
 215
 216                         bool b = false;
 217
 218                         if ((ret = (*i)->roll (nframes, start_sample, end_sample, declick, b)) < 0) {
 219                                 stop_transport ();
 220                                 return -1;
 221                         }
 222
 223                         if (b) {
 224                                 DEBUG_TRACE (DEBUG::Butler, string_compose ("%1 rolled and needs butler\n", (*i)->name()));
 225                                 need_butler = true;
 226                         }
 227                 }
 228         }
 229
 230         return 0;
 231 }
 232
 233 void
 234 Session::get_track_statistics ()
 235 {
 236         float pworst = 1.0f;
 237         float cworst = 1.0f;
 238
 239         boost::shared_ptr<RouteList> rl = routes.reader();
 240         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 241
 242                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 243
 244                 if (!tr || tr->is_private_route()) {
 245                         continue;
 246                 }
 247
 248                 pworst = min (pworst, tr->playback_buffer_load());
 249                 cworst = min (cworst, tr->capture_buffer_load());
 250         }
 251
 252         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 253         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 254
 255         if (actively_recording()) {
 256                 set_dirty();
 257         }
 258 }
 259
 260 /** Process callback used when the auditioner is not active */
 261 void
 262 Session::process_with_events (pframes_t nframes)
 263 {
 264         PT_TIMING_CHECK (3);
 265
 266         SessionEvent*  ev;
 267         pframes_t      this_nframes;
 268         samplepos_t     end_sample;
 269         bool           session_needs_butler = false;
 270         samplecnt_t     samples_moved;
 271
 272         /* make sure the auditioner is silent */
 273
 274         if (auditioner) {
 275                 auditioner->silence (nframes);
 276         }
 277
 278         /* handle any pending events */
 279
 280         while (pending_events.read (&ev, 1) == 1) {
 281                 merge_event (ev);
 282         }
 283
 284         /* if we are not in the middle of a state change,
 285            and there are immediate events queued up,
 286            process them.
 287         */
 288
 289         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 290                 SessionEvent *ev = immediate_events.front ();
 291                 immediate_events.pop_front ();
 292                 process_event (ev);
 293         }
 294
 295         /* only count-in when going to roll at speed 1.0 */
 296         if (_transport_speed != 1.0 && _count_in_samples > 0) {
 297                 _count_in_samples = 0;
 298         }
 299         if (_transport_speed == 0.0) {
 300                 _remaining_latency_preroll = 0;
 301         }
 302
 303         assert (_count_in_samples == 0 || _remaining_latency_preroll == 0 || _count_in_samples == _remaining_latency_preroll);
 304
 305         if (_count_in_samples > 0 || _remaining_latency_preroll > 0) {
 306                 samplecnt_t ns;
 307
 308                 if (_remaining_latency_preroll > 0) {
 309                         ns = std::min ((samplecnt_t)nframes, _remaining_latency_preroll);
 310                 } else {
 311                         ns = std::min ((samplecnt_t)nframes, _count_in_samples);
 312                 }
 313
 314                 if (_count_in_samples > 0) {
 315                         run_click (_transport_sample - _count_in_samples, ns);
 316                         assert (_count_in_samples >= ns);
 317                         _count_in_samples -= ns;
 318                 }
 319
 320                 if (_remaining_latency_preroll > 0) {
 321                         if (_count_in_samples == 0) {
 322                                 click (_transport_sample - _remaining_latency_preroll, ns);
 323                         }
 324                         if (process_routes (ns, session_needs_butler)) {
 325                                 fail_roll (ns);
 326                         }
 327                 } else {
 328                         no_roll (ns);
 329                 }
 330
 331                 if (_remaining_latency_preroll > 0) {
 332                         assert (_remaining_latency_preroll >= ns);
 333                         _remaining_latency_preroll -= ns;
 334                 }
 335
 336                 nframes -= ns;
 337
 338                 /* process events.. */
 339                 if (!events.empty() && next_event != events.end()) {
 340                         SessionEvent* this_event = *next_event;
 341                         Events::iterator the_next_one = next_event;
 342                         ++the_next_one;
 343
 344                         while (this_event && this_event->action_sample == _transport_sample) {
 345                                 process_event (this_event);
 346                                 if (the_next_one == events.end()) {
 347                                         this_event = 0;
 348                                 } else {
 349                                         this_event = *the_next_one;
 350                                         ++the_next_one;
 351                                 }
 352                         }
 353                         set_next_event ();
 354                 }
 355
 356                 check_declick_out ();
 357
 358                 if (nframes == 0) {
 359                         return;
 360                 } else {
 361                         _engine.split_cycle (ns);
 362                 }
 363         }
 364
 365         /* Decide on what to do with quarter-frame MTC during this cycle */
 366
 367         bool const was_sending_qf_mtc = _send_qf_mtc;
 368         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 369
 370         if (_transport_speed != 0) {
 371                 _send_qf_mtc = (
 372                         Config->get_send_mtc () &&
 373                         _transport_speed >= (1 - tolerance) &&
 374                         _transport_speed <= (1 + tolerance)
 375                         );
 376
 377                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 378                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 379                         _send_timecode_update = true;
 380                 }
 381
 382                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (sample_rate () / 4)) {
 383                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 384                            a quarter of a second since we sent anything at all, so send a full MTC update
 385                            this cycle.
 386                         */
 387                         _send_timecode_update = true;
 388                 }
 389
 390                 _pframes_since_last_mtc += nframes;
 391         }
 392
 393         /* Events caused a transport change (or we re-started sending
 394          * MTC), so send an MTC Full Frame (Timecode) message.  This
 395          * is sent whether rolling or not, to give slaves an idea of
 396          * ardour time on locates (and allow slow slaves to position
 397          * and prepare for rolling)
 398          */
 399         if (_send_timecode_update) {
 400                 send_full_time_code (_transport_sample, nframes);
 401         }
 402
 403         if (!process_can_proceed()) {
 404                 _silent = true;
 405                 return;
 406         }
 407
 408         if (events.empty() || next_event == events.end()) {
 409                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 410                 /* lua scripts may inject events */
 411                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 412                         merge_event (ev);
 413                 }
 414                 if (events.empty() || next_event == events.end()) {
 415                         process_without_events (nframes);
 416                         return;
 417                 }
 418         }
 419
 420         if (_transport_speed == 1.0) {
 421                 samples_moved = (samplecnt_t) nframes;
 422         } else {
 423                 interpolation.set_target_speed (_target_transport_speed);
 424                 interpolation.set_speed (_transport_speed);
 425                 samples_moved = (samplecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 426         }
 427
 428         end_sample = _transport_sample + samples_moved;
 429
 430         {
 431                 SessionEvent* this_event;
 432                 Events::iterator the_next_one;
 433
 434                 if (!process_can_proceed()) {
 435                         _silent = true;
 436                         return;
 437                 }
 438
 439                 if (!_exporting && _slave) {
 440                         if (!follow_slave (nframes)) {
 441                                 return;
 442                         }
 443                 }
 444
 445                 if (_transport_speed == 0) {
 446                         no_roll (nframes);
 447                         return;
 448                 }
 449
 450                 if (!_exporting && !timecode_transmission_suspended()) {
 451                         send_midi_time_code_for_cycle (_transport_sample, end_sample, nframes);
 452                 }
 453
 454                 ltc_tx_send_time_code_for_cycle (_transport_sample, end_sample, _target_transport_speed, _transport_speed, nframes);
 455
 456                 samplepos_t stop_limit = compute_stop_limit ();
 457
 458                 if (maybe_stop (stop_limit)) {
 459                         no_roll (nframes);
 460                         return;
 461                 }
 462
 463                 this_event = *next_event;
 464                 the_next_one = next_event;
 465                 ++the_next_one;
 466
 467                 /* yes folks, here it is, the actual loop where we really truly
 468                    process some audio
 469                 */
 470
 471                 while (nframes) {
 472
 473                         this_nframes = nframes; /* real (jack) time relative */
 474                         samples_moved = (samplecnt_t) floor (_transport_speed * nframes); /* transport relative */
 475
 476                         /* running an event, position transport precisely to its time */
 477                         if (this_event && this_event->action_sample <= end_sample && this_event->action_sample >= _transport_sample) {
 478                                 /* this isn't quite right for reverse play */
 479                                 samples_moved = (samplecnt_t) (this_event->action_sample - _transport_sample);
 480                                 this_nframes = abs (floor(samples_moved / _transport_speed));
 481                         }
 482
 483                         try_run_lua (this_nframes);
 484
 485                         if (this_nframes) {
 486
 487                                 click (_transport_sample, this_nframes);
 488
 489                                 if (process_routes (this_nframes, session_needs_butler)) {
 490                                         fail_roll (nframes);
 491                                         return;
 492                                 }
 493
 494                                 get_track_statistics ();
 495
 496                                 nframes -= this_nframes;
 497
 498                                 if (samples_moved < 0) {
 499                                         decrement_transport_position (-samples_moved);
 500                                 } else if (samples_moved) {
 501                                         increment_transport_position (samples_moved);
 502                                 }
 503
 504                                 maybe_stop (stop_limit);
 505                                 check_declick_out ();
 506                         }
 507
 508                         if (nframes > 0) {
 509                                 _engine.split_cycle (this_nframes);
 510                         }
 511
 512                         /* now handle this event and all others scheduled for the same time */
 513
 514                         while (this_event && this_event->action_sample == _transport_sample) {
 515                                 process_event (this_event);
 516
 517                                 if (the_next_one == events.end()) {
 518                                         this_event = 0;
 519                                 } else {
 520                                         this_event = *the_next_one;
 521                                         ++the_next_one;
 522                                 }
 523                         }
 524
 525                         /* if an event left our state changing, do the right thing */
 526
 527                         if (nframes && non_realtime_work_pending()) {
 528                                 no_roll (nframes);
 529                                 break;
 530                         }
 531
 532                         /* this is necessary to handle the case of seamless looping */
 533                         end_sample = _transport_sample + floor (nframes * _transport_speed);
 534                 }
 535
 536                 set_next_event ();
 537
 538         } /* implicit release of route lock */
 539
 540         if (session_needs_butler) {
 541                 DEBUG_TRACE (DEBUG::Butler, "p-with-events: session needs butler, call it\n");
 542                 _butler->summon ();
 543         }
 544 }
 545
 546 void
 547 Session::reset_slave_state ()
 548 {
 549         average_slave_delta = 1800;
 550         delta_accumulator_cnt = 0;
 551         have_first_delta_accumulator = false;
 552         _slave_state = Stopped;
 553         DiskReader::set_no_disk_output (false);
 554 }
 555
 556 bool
 557 Session::transport_locked () const
 558 {
 559         Slave* sl = _slave;
 560
 561         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 562                 return true;
 563         }
 564
 565         return false;
 566 }
 567
 568 bool
 569 Session::follow_slave (pframes_t nframes)
 570 {
 571         double slave_speed;
 572         samplepos_t slave_transport_sample;
 573         samplecnt_t this_delta;
 574         int dir;
 575
 576         if (!_slave->ok()) {
 577                 stop_transport ();
 578                 config.set_external_sync (false);
 579                 goto noroll;
 580         }
 581
 582         _slave->speed_and_position (slave_speed, slave_transport_sample);
 583
 584         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_sample, slave_speed));
 585
 586         if (!_slave->locked()) {
 587                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 588                 goto noroll;
 589         }
 590
 591         if (slave_transport_sample > _transport_sample) {
 592                 this_delta = slave_transport_sample - _transport_sample;
 593                 dir = 1;
 594         } else {
 595                 this_delta = _transport_sample - slave_transport_sample;
 596                 dir = -1;
 597         }
 598
 599         if (_slave->starting()) {
 600                 slave_speed = 0.0f;
 601         }
 602
 603         if (_slave->is_always_synced() ||
 604                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 605                         ) {
 606
 607                 /* if the TC source is synced, then we assume that its
 608                    speed is binary: 0.0 or 1.0
 609                 */
 610
 611                 if (slave_speed != 0.0f) {
 612                         slave_speed = 1.0f;
 613                 }
 614
 615         } else {
 616
 617                 /* if we are chasing and the average delta between us and the
 618                    master gets too big, we want to switch to silent
 619                    motion. so keep track of that here.
 620                 */
 621
 622                 if (_slave_state == Running) {
 623                         calculate_moving_average_of_slave_delta(dir, abs(this_delta));
 624                 }
 625         }
 626
 627         track_slave_state (slave_speed, slave_transport_sample, this_delta);
 628
 629         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 630                                                    _slave_state, slave_transport_sample, slave_speed, this_delta, average_slave_delta));
 631
 632
 633         if (_slave_state == Running && !_slave->is_always_synced() && !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)) {
 634
 635                 /* may need to varispeed to sync with slave */
 636
 637                 if (_transport_speed != 0.0f) {
 638
 639                         /*
 640                            note that average_dir is +1 or -1
 641                         */
 642
 643                         float delta;
 644
 645                         if (average_slave_delta == 0) {
 646                                 delta = this_delta;
 647                                 delta *= dir;
 648                         } else {
 649                                 delta = average_slave_delta;
 650                                 delta *= average_dir;
 651                         }
 652
 653 #ifndef NDEBUG
 654                         if (slave_speed != 0.0) {
 655                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 656                                                                            (int) (dir * this_delta),
 657                                                                            slave_speed,
 658                                                                            _transport_speed,
 659                                                                            _transport_sample,
 660                                                                            slave_transport_sample,
 661                                                                            average_slave_delta));
 662                         }
 663 #endif
 664
 665                         if (_slave->give_slave_full_control_over_transport_speed()) {
 666                                 set_transport_speed (slave_speed, 0, false, false);
 667                                 //std::cout << "set speed = " << slave_speed << "\n";
 668                         } else {
 669                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_sample_rate)));
 670                                 request_transport_speed (adjusted_speed);
 671                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 672                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 673                                                                            slave_speed));
 674                         }
 675
 676                         if (!actively_recording() && (samplecnt_t) average_slave_delta > _slave->resolution()) {
 677                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("average slave delta %1 greater than slave resolution %2 => no disk output\n", average_slave_delta, _slave->resolution()));
 678                                 /* run routes as normal, but no disk output */
 679                                 DiskReader::set_no_disk_output (true);
 680                                 return true;
 681                         }
 682
 683                         if (!have_first_delta_accumulator) {
 684                                 DEBUG_TRACE (DEBUG::Slave, "waiting for first slave delta accumulator to be ready, no disk output\n");
 685                                 /* run routes as normal, but no disk output */
 686                                 DiskReader::set_no_disk_output (true);
 687                                 return true;
 688                         }
 689                 }
 690         }
 691
 692
 693         if (!have_first_delta_accumulator) {
 694                 DEBUG_TRACE (DEBUG::Slave, "still waiting to compute slave delta, no disk output\n");
 695                 DiskReader::set_no_disk_output (true);
 696         } else {
 697                 DiskReader::set_no_disk_output (false);
 698         }
 699
 700         if ((_slave_state == Running) && (0 == (post_transport_work () & ~PostTransportSpeed))) {
 701                 /* speed is set, we're locked, and good to go */
 702                 return true;
 703         }
 704
 705   noroll:
 706         /* don't move at all */
 707         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 708         no_roll (nframes);
 709         return false;
 710 }
 711
 712 void
 713 Session::calculate_moving_average_of_slave_delta (int dir, samplecnt_t this_delta)
 714 {
 715         if (delta_accumulator_cnt >= delta_accumulator_size) {
 716                 have_first_delta_accumulator = true;
 717                 delta_accumulator_cnt = 0;
 718         }
 719
 720         if (delta_accumulator_cnt != 0 || this_delta < _current_sample_rate) {
 721                 delta_accumulator[delta_accumulator_cnt++] = (samplecnt_t) dir *  (samplecnt_t) this_delta;
 722         }
 723
 724         if (have_first_delta_accumulator) {
 725                 average_slave_delta = 0L;
 726                 for (int i = 0; i < delta_accumulator_size; ++i) {
 727                         average_slave_delta += delta_accumulator[i];
 728                 }
 729                 average_slave_delta /= (int32_t) delta_accumulator_size;
 730                 if (average_slave_delta < 0L) {
 731                         average_dir = -1;
 732                         average_slave_delta = average_slave_delta;
 733                 } else {
 734                         average_dir = 1;
 735                 }
 736         }
 737 }
 738
 739 void
 740 Session::track_slave_state (float slave_speed, samplepos_t slave_transport_sample, samplecnt_t /*this_delta*/)
 741 {
 742         if (slave_speed != 0.0f) {
 743
 744                 /* slave is running */
 745
 746                 switch (_slave_state) {
 747                 case Stopped:
 748                         if (_slave->requires_seekahead()) {
 749                                 slave_wait_end = slave_transport_sample + _slave->seekahead_distance ();
 750                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 751                                 /* we can call locate() here because we are in process context */
 752                                 locate (slave_wait_end, false, false);
 753                                 _slave_state = Waiting;
 754
 755                         } else {
 756
 757                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_sample));
 758
 759                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 760                                 average_slave_delta = 0L;
 761
 762                                 Location* al = _locations->auto_loop_location();
 763
 764                                 if (al && play_loop && (slave_transport_sample < al->start() || slave_transport_sample > al->end())) {
 765                                         // cancel looping
 766                                         request_play_loop(false);
 767                                 }
 768
 769                                 if (slave_transport_sample != _transport_sample) {
 770                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_sample, slave_transport_sample));
 771                                         locate (slave_transport_sample, false, false);
 772                                 }
 773                                 _slave_state = Running;
 774                         }
 775                         break;
 776
 777                 case Waiting:
 778                 default:
 779                         break;
 780                 }
 781
 782                 if (_slave_state == Waiting) {
 783
 784                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_sample));
 785
 786                         if (slave_transport_sample >= slave_wait_end) {
 787
 788                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_sample, _transport_sample));
 789
 790                                 _slave_state = Running;
 791
 792                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 793                                    precisely with the master.
 794                                 */
 795
 796
 797                                 bool ok = true;
 798                                 samplecnt_t sample_delta = slave_transport_sample - _transport_sample;
 799
 800                                 boost::shared_ptr<RouteList> rl = routes.reader();
 801                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 802                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 803                                         if (tr && !tr->can_internal_playback_seek (sample_delta)) {
 804                                                 ok = false;
 805                                                 break;
 806                                         }
 807                                 }
 808
 809                                 if (ok) {
 810                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 811                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 812                                                 if (tr) {
 813                                                         tr->internal_playback_seek (sample_delta);
 814                                                 }
 815                                         }
 816                                         _transport_sample += sample_delta;
 817
 818                                 } else {
 819                                         cerr << "cannot micro-seek\n";
 820                                         /* XXX what? */
 821                                 }
 822                         }
 823                 }
 824
 825                 if (_slave_state == Running && _transport_speed == 0.0f) {
 826                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 827                         start_transport ();
 828                 }
 829
 830         } else { // slave_speed is 0
 831
 832                 /* slave has stopped */
 833
 834                 if (_transport_speed != 0.0f) {
 835                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 sample %2 tf %3\n", slave_speed, slave_transport_sample, _transport_sample));
 836                         stop_transport ();
 837                 }
 838
 839                 if (slave_transport_sample != _transport_sample) {
 840                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_sample));
 841                         force_locate (slave_transport_sample, false);
 842                 }
 843
 844                 reset_slave_state();
 845         }
 846 }
 847
 848 void
 849 Session::process_without_events (pframes_t nframes)
 850 {
 851         bool session_needs_butler = false;
 852         samplecnt_t samples_moved;
 853
 854         if (!process_can_proceed()) {
 855                 _silent = true;
 856                 return;
 857         }
 858
 859         if (!_exporting && _slave) {
 860                 if (!follow_slave (nframes)) {
 861                         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample, 0, 0 , nframes);
 862                         return;
 863                 }
 864         }
 865
 866         if (_transport_speed == 0) {
 867                 no_roll (nframes);
 868                 return;
 869         }
 870
 871         if (_transport_speed == 1.0) {
 872                 samples_moved = (samplecnt_t) nframes;
 873         } else {
 874                 interpolation.set_target_speed (_target_transport_speed);
 875                 interpolation.set_speed (_transport_speed);
 876                 samples_moved = (samplecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 877         }
 878
 879         if (!_exporting && !timecode_transmission_suspended()) {
 880                 send_midi_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, nframes);
 881         }
 882
 883         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, _target_transport_speed, _transport_speed, nframes);
 884
 885         samplepos_t const stop_limit = compute_stop_limit ();
 886
 887         if (maybe_stop (stop_limit)) {
 888                 no_roll (nframes);
 889                 return;
 890         }
 891
 892         if (maybe_sync_start (nframes)) {
 893                 return;
 894         }
 895
 896         click (_transport_sample, nframes);
 897
 898         if (process_routes (nframes, session_needs_butler)) {
 899                 fail_roll (nframes);
 900                 return;
 901         }
 902
 903         get_track_statistics ();
 904
 905         if (samples_moved < 0) {
 906                 decrement_transport_position (-samples_moved);
 907         } else if (samples_moved) {
 908                 increment_transport_position (samples_moved);
 909         }
 910
 911         maybe_stop (stop_limit);
 912         check_declick_out ();
 913
 914         if (session_needs_butler) {
 915                 DEBUG_TRACE (DEBUG::Butler, "p-without-events: session needs butler, call it\n");
 916                 _butler->summon ();
 917         }
 918 }
 919
 920 /** Process callback used when the auditioner is active.
 921  * @param nframes number of samples to process.
 922  */
 923 void
 924 Session::process_audition (pframes_t nframes)
 925 {
 926         SessionEvent* ev;
 927         boost::shared_ptr<RouteList> r = routes.reader ();
 928
 929         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 930                 if (!(*i)->is_auditioner()) {
 931                         (*i)->silence (nframes);
 932                 }
 933         }
 934
 935         /* run the auditioner, and if it says we need butler service, ask for it */
 936
 937         if (auditioner->play_audition (nframes) > 0) {
 938                 DEBUG_TRACE (DEBUG::Butler, "auditioner needs butler, call it\n");
 939                 _butler->summon ();
 940         }
 941
 942         /* if using a monitor section, run it because otherwise we don't hear anything */
 943
 944         if (_monitor_out && auditioner->needs_monitor()) {
 945                 _monitor_out->monitor_run (_transport_sample, _transport_sample + nframes, nframes, false);
 946         }
 947
 948         /* handle pending events */
 949
 950         while (pending_events.read (&ev, 1) == 1) {
 951                 merge_event (ev);
 952         }
 953
 954         /* if we are not in the middle of a state change,
 955            and there are immediate events queued up,
 956            process them.
 957         */
 958
 959         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 960                 SessionEvent *ev = immediate_events.front ();
 961                 immediate_events.pop_front ();
 962                 process_event (ev);
 963         }
 964
 965         if (!auditioner->auditioning()) {
 966                 /* auditioner no longer active, so go back to the normal process callback */
 967                 process_function = &Session::process_with_events;
 968         }
 969 }
 970
 971 bool
 972 Session::maybe_sync_start (pframes_t & nframes)
 973 {
 974         pframes_t sync_offset;
 975
 976         if (!waiting_for_sync_offset) {
 977                 return false;
 978         }
 979
 980         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 981
 982                 /* generate silence up to the sync point, then
 983                    adjust nframes + offset to reflect whatever
 984                    is left to do.
 985                 */
 986
 987                 no_roll (sync_offset);
 988                 nframes -= sync_offset;
 989                 Port::increment_global_port_buffer_offset (sync_offset);
 990                 waiting_for_sync_offset = false;
 991
 992                 if (nframes == 0) {
 993                         return true; // done, nothing left to process
 994                 }
 995
 996         } else {
 997
 998                 /* sync offset point is not within this process()
 999                    cycle, so just generate silence. and don't bother
1000                    with any fancy stuff here, just the minimal silence.
1001                 */
1002
1003                 _silent = true;
1004
1005                 if (Config->get_locate_while_waiting_for_sync()) {
1006                         if (micro_locate (nframes)) {
1007                                 /* XXX ERROR !!! XXX */
1008                         }
1009                 }
1010
1011                 return true; // done, nothing left to process
1012         }
1013
1014         return false;
1015 }
1016
1017 void
1018 Session::queue_event (SessionEvent* ev)
1019 {
1020         if (_state_of_the_state & Deletion) {
1021                 return;
1022         } else if (_state_of_the_state & Loading) {
1023                 merge_event (ev);
1024         } else {
1025                 Glib::Threads::Mutex::Lock lm (rb_write_lock);
1026                 pending_events.write (&ev, 1);
1027         }
1028 }
1029
1030 void
1031 Session::set_next_event ()
1032 {
1033         if (events.empty()) {
1034                 next_event = events.end();
1035                 return;
1036         }
1037
1038         if (next_event == events.end()) {
1039                 next_event = events.begin();
1040         }
1041
1042         if ((*next_event)->action_sample > _transport_sample) {
1043                 next_event = events.begin();
1044         }
1045
1046         for (; next_event != events.end(); ++next_event) {
1047                 if ((*next_event)->action_sample >= _transport_sample) {
1048                         break;
1049                 }
1050         }
1051 }
1052
1053 void
1054 Session::process_event (SessionEvent* ev)
1055 {
1056         bool remove = true;
1057         bool del = true;
1058
1059         /* if we're in the middle of a state change (i.e. waiting
1060            for the butler thread to complete the non-realtime
1061            part of the change), we'll just have to queue this
1062            event for a time when the change is complete.
1063         */
1064
1065         if (non_realtime_work_pending()) {
1066
1067                 /* except locates, which we have the capability to handle */
1068
1069                 if (ev->type != SessionEvent::Locate) {
1070                         immediate_events.insert (immediate_events.end(), ev);
1071                         _remove_event (ev);
1072                         return;
1073                 }
1074         }
1075
1076         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_sample));
1077
1078         switch (ev->type) {
1079         case SessionEvent::SetLoop:
1080                 set_play_loop (ev->yes_or_no, ev->speed);
1081                 break;
1082
1083         case SessionEvent::AutoLoop:
1084                 if (play_loop) {
1085                         /* roll after locate, do not flush, set "with loop"
1086                            true only if we are seamless looping
1087                         */
1088                         start_locate (ev->target_sample, true, false, Config->get_seamless_loop());
1089                 }
1090                 remove = false;
1091                 del = false;
1092                 break;
1093
1094         case SessionEvent::AutoLoopDeclick:
1095                 if (play_loop) {
1096                         /* Request a declick fade-out and a fade-in; the fade-out will happen
1097                            at the end of the loop, and the fade-in at the start.
1098                         */
1099                         transport_sub_state |= (PendingLoopDeclickOut | PendingLoopDeclickIn);
1100                 }
1101                 remove = false;
1102                 del = false;
1103                 break;
1104
1105         case SessionEvent::Locate:
1106                 if (ev->yes_or_no) { /* force locate */
1107                         /* args: do not roll after locate, do flush, not with loop */
1108                         locate (ev->target_sample, false, true, false);
1109                 } else {
1110                         /* args: do not roll after locate, do flush, not with loop */
1111                         start_locate (ev->target_sample, false, true, false);
1112                 }
1113                 _send_timecode_update = true;
1114                 break;
1115
1116         case SessionEvent::LocateRoll:
1117                 if (ev->yes_or_no) {
1118                         /* args: roll after locate, do flush, not with loop */
1119                         locate (ev->target_sample, true, true, false);
1120                 } else {
1121                         /* args: roll after locate, do flush, not with loop */
1122                         start_locate (ev->target_sample, true, true, false);
1123                 }
1124                 _send_timecode_update = true;
1125                 break;
1126
1127         case SessionEvent::Skip:
1128                 if (Config->get_skip_playback()) {
1129                         start_locate (ev->target_sample, true, true, false);
1130                         _send_timecode_update = true;
1131                 }
1132                 remove = false;
1133                 del = false;
1134                 break;
1135
1136         case SessionEvent::LocateRollLocate:
1137                 // locate is handled by ::request_roll_at_and_return()
1138                 _requested_return_sample = ev->target_sample;
1139                 request_locate (ev->target2_sample, true);
1140                 break;
1141
1142
1143         case SessionEvent::SetTransportSpeed:
1144                 set_transport_speed (ev->speed, ev->target_sample, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1145                 break;
1146
1147         case SessionEvent::PunchIn:
1148                 // cerr << "PunchIN at " << transport_sample() << endl;
1149                 if (config.get_punch_in() && record_status() == Enabled) {
1150                         enable_record ();
1151                 }
1152                 remove = false;
1153                 del = false;
1154                 break;
1155
1156         case SessionEvent::PunchOut:
1157                 // cerr << "PunchOUT at " << transport_sample() << endl;
1158                 if (config.get_punch_out()) {
1159                         step_back_from_record ();
1160                 }
1161                 remove = false;
1162                 del = false;
1163                 break;
1164
1165         case SessionEvent::StopOnce:
1166                 if (!non_realtime_work_pending()) {
1167                         _clear_event_type (SessionEvent::StopOnce);
1168                         stop_transport (ev->yes_or_no);
1169                 }
1170                 remove = false;
1171                 del = false;
1172                 break;
1173
1174         case SessionEvent::RangeStop:
1175                 if (!non_realtime_work_pending()) {
1176                         stop_transport (ev->yes_or_no);
1177                 }
1178                 remove = false;
1179                 del = false;
1180                 break;
1181
1182         case SessionEvent::RangeLocate:
1183                 /* args: roll after locate, do flush, not with loop */
1184                 start_locate (ev->target_sample, true, true, false);
1185                 remove = false;
1186                 del = false;
1187                 break;
1188
1189         case SessionEvent::Overwrite:
1190                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1191                 break;
1192
1193         case SessionEvent::SetSyncSource:
1194                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1195                 use_sync_source (ev->slave);
1196                 break;
1197
1198         case SessionEvent::Audition:
1199                 set_audition (ev->region);
1200                 // drop reference to region
1201                 ev->region.reset ();
1202                 break;
1203
1204         case SessionEvent::SetPlayAudioRange:
1205                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1206                 break;
1207
1208         case SessionEvent::CancelPlayAudioRange:
1209                 unset_play_range();
1210                 break;
1211
1212         case SessionEvent::RealTimeOperation:
1213                 process_rtop (ev);
1214                 del = false; // other side of RT request needs to clean up
1215                 break;
1216
1217         case SessionEvent::AdjustPlaybackBuffering:
1218                 schedule_playback_buffering_adjustment ();
1219                 break;
1220
1221         case SessionEvent::AdjustCaptureBuffering:
1222                 schedule_capture_buffering_adjustment ();
1223                 break;
1224
1225         case SessionEvent::SetTimecodeTransmission:
1226                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1227                 break;
1228
1229         default:
1230           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1231                 abort(); /*NOTREACHED*/
1232                 break;
1233         };
1234
1235         if (remove) {
1236                 del = del && !_remove_event (ev);
1237         }
1238
1239         if (del) {
1240                 delete ev;
1241         }
1242 }
1243
1244 samplepos_t
1245 Session::compute_stop_limit () const
1246 {
1247         if (!Config->get_stop_at_session_end ()) {
1248                 return max_samplepos;
1249         }
1250
1251         if (_slave) {
1252                 return max_samplepos;
1253         }
1254
1255         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1256         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1257
1258         if (actively_recording ()) {
1259                 /* permanently recording */
1260                 return max_samplepos;
1261         } else if (punching_in && !punching_out) {
1262                 /* punching in but never out */
1263                 return max_samplepos;
1264         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_sample()) {
1265                 /* punching in and punching out after session end */
1266                 return max_samplepos;
1267         }
1268
1269         return current_end_sample ();
1270 }
1271
1272
1273
1274 /* dedicated thread for signal emission.
1275  *
1276  * while sending cross-thread signals from the process thread
1277  * is fine in general, PBD::Signal's use of boost::function and
1278  * boost:bind can produce a vast overhead which is not
1279  * acceptable for low latency.
1280  *
1281  * This works around the issue by moving the boost overhead
1282  * out of the RT thread. The overall load is probably higher but
1283  * the realtime thread remains unaffected.
1284  */
1285
1286 void
1287 Session::emit_route_signals ()
1288 {
1289         // TODO use RAII to allow using these signals in other places
1290         BatchUpdateStart(); /* EMIT SIGNAL */
1291         boost::shared_ptr<RouteList> r = routes.reader ();
1292         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1293                 (*ci)->emit_pending_signals ();
1294         }
1295         BatchUpdateEnd(); /* EMIT SIGNAL */
1296 }
1297
1298 void
1299 Session::emit_thread_start ()
1300 {
1301         if (_rt_thread_active) {
1302                 return;
1303         }
1304         _rt_thread_active = true;
1305
1306         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1307                 _rt_thread_active = false;
1308         }
1309 }
1310
1311 void
1312 Session::emit_thread_terminate ()
1313 {
1314         if (!_rt_thread_active) {
1315                 return;
1316         }
1317         _rt_thread_active = false;
1318
1319         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1320                 pthread_cond_signal (&_rt_emit_cond);
1321                 pthread_mutex_unlock (&_rt_emit_mutex);
1322         }
1323
1324         void *status;
1325         pthread_join (_rt_emit_thread, &status);
1326 }
1327
1328 void *
1329 Session::emit_thread (void *arg)
1330 {
1331         Session *s = static_cast<Session *>(arg);
1332         s->emit_thread_run ();
1333         pthread_exit (0);
1334         return 0;
1335 }
1336
1337 void
1338 Session::emit_thread_run ()
1339 {
1340         pthread_mutex_lock (&_rt_emit_mutex);
1341         while (_rt_thread_active) {
1342                 emit_route_signals();
1343                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1344         }
1345         pthread_mutex_unlock (&_rt_emit_mutex);
1346 }