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                 boost::shared_ptr<RouteList> r = routes.reader ();
 315                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 316                         samplecnt_t route_offset = (*i)->playback_latency ();
 317                         if (_remaining_latency_preroll > route_offset + ns) {
 318                                 /* route will no-roll for complete pre-roll cycle */
 319                                 continue;
 320                         }
 321                         if (_remaining_latency_preroll > route_offset) {
 322                                 /* route may need partial no-roll and partial roll from
 323                                 * (_transport_sample - _remaining_latency_preroll) ..  +ns.
 324                                 * shorten and split the cycle.
 325                                 */
 326                                 ns = std::min (ns, (_remaining_latency_preroll - route_offset));
 327                         }
 328                 }
 329
 330                 if (_count_in_samples > 0) {
 331                         run_click (_transport_sample - _count_in_samples, ns);
 332                         assert (_count_in_samples >= ns);
 333                         _count_in_samples -= ns;
 334                 }
 335
 336                 if (_remaining_latency_preroll > 0) {
 337                         if (_count_in_samples == 0) {
 338                                 click (_transport_sample - _remaining_latency_preroll, ns);
 339                         }
 340                         if (process_routes (ns, session_needs_butler)) {
 341                                 fail_roll (ns);
 342                         }
 343                 } else {
 344                         no_roll (ns);
 345                 }
 346
 347                 if (_remaining_latency_preroll > 0) {
 348                         assert (_remaining_latency_preroll >= ns);
 349                         _remaining_latency_preroll -= ns;
 350                 }
 351
 352                 nframes -= ns;
 353
 354                 /* process events.. */
 355                 if (!events.empty() && next_event != events.end()) {
 356                         SessionEvent* this_event = *next_event;
 357                         Events::iterator the_next_one = next_event;
 358                         ++the_next_one;
 359
 360                         while (this_event && this_event->action_sample == _transport_sample) {
 361                                 process_event (this_event);
 362                                 if (the_next_one == events.end()) {
 363                                         this_event = 0;
 364                                 } else {
 365                                         this_event = *the_next_one;
 366                                         ++the_next_one;
 367                                 }
 368                         }
 369                         set_next_event ();
 370                 }
 371
 372                 check_declick_out ();
 373
 374                 if (nframes == 0) {
 375                         return;
 376                 } else {
 377                         _engine.split_cycle (ns);
 378                 }
 379         }
 380
 381         /* Decide on what to do with quarter-frame MTC during this cycle */
 382
 383         bool const was_sending_qf_mtc = _send_qf_mtc;
 384         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 385
 386         if (_transport_speed != 0) {
 387                 _send_qf_mtc = (
 388                         Config->get_send_mtc () &&
 389                         _transport_speed >= (1 - tolerance) &&
 390                         _transport_speed <= (1 + tolerance)
 391                         );
 392
 393                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 394                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 395                         _send_timecode_update = true;
 396                 }
 397
 398                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (sample_rate () / 4)) {
 399                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 400                            a quarter of a second since we sent anything at all, so send a full MTC update
 401                            this cycle.
 402                         */
 403                         _send_timecode_update = true;
 404                 }
 405
 406                 _pframes_since_last_mtc += nframes;
 407         }
 408
 409         /* Events caused a transport change (or we re-started sending
 410          * MTC), so send an MTC Full Frame (Timecode) message.  This
 411          * is sent whether rolling or not, to give slaves an idea of
 412          * ardour time on locates (and allow slow slaves to position
 413          * and prepare for rolling)
 414          */
 415         if (_send_timecode_update) {
 416                 send_full_time_code (_transport_sample, nframes);
 417         }
 418
 419         if (!process_can_proceed()) {
 420                 _silent = true;
 421                 return;
 422         }
 423
 424         if (events.empty() || next_event == events.end()) {
 425                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 426                 /* lua scripts may inject events */
 427                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 428                         merge_event (ev);
 429                 }
 430                 if (events.empty() || next_event == events.end()) {
 431                         process_without_events (nframes);
 432                         return;
 433                 }
 434         }
 435
 436         if (_transport_speed == 1.0) {
 437                 samples_moved = (samplecnt_t) nframes;
 438         } else {
 439                 /* use a cubic midi interpolation to compute the number of
 440                  * samples we will move at the current speed.
 441                  */
 442                 CubicInterpolation interp;
 443                 interp.set_speed (_transport_speed);
 444                 samples_moved = interp.distance (nframes);
 445         }
 446
 447         end_sample = _transport_sample + samples_moved;
 448
 449         {
 450                 SessionEvent* this_event;
 451                 Events::iterator the_next_one;
 452
 453                 if (!process_can_proceed()) {
 454                         _silent = true;
 455                         return;
 456                 }
 457
 458                 if (!_exporting && _slave) {
 459                         if (!follow_slave (nframes)) {
 460                                 return;
 461                         }
 462                 }
 463
 464                 if (_transport_speed == 0) {
 465                         no_roll (nframes);
 466                         return;
 467                 }
 468
 469                 if (!_exporting && !timecode_transmission_suspended()) {
 470                         send_midi_time_code_for_cycle (_transport_sample, end_sample, nframes);
 471                 }
 472
 473                 ltc_tx_send_time_code_for_cycle (_transport_sample, end_sample, _target_transport_speed, _transport_speed, nframes);
 474
 475                 samplepos_t stop_limit = compute_stop_limit ();
 476
 477                 if (maybe_stop (stop_limit)) {
 478                         no_roll (nframes);
 479                         return;
 480                 }
 481
 482                 this_event = *next_event;
 483                 the_next_one = next_event;
 484                 ++the_next_one;
 485
 486                 /* yes folks, here it is, the actual loop where we really truly
 487                    process some audio
 488                 */
 489
 490                 while (nframes) {
 491
 492                         this_nframes = nframes; /* real (jack) time relative */
 493                         samples_moved = (samplecnt_t) floor (_transport_speed * nframes); /* transport relative */
 494
 495                         /* running an event, position transport precisely to its time */
 496                         if (this_event && this_event->action_sample <= end_sample && this_event->action_sample >= _transport_sample) {
 497                                 /* this isn't quite right for reverse play */
 498                                 samples_moved = (samplecnt_t) (this_event->action_sample - _transport_sample);
 499                                 this_nframes = abs (floor(samples_moved / _transport_speed));
 500                         }
 501
 502                         try_run_lua (this_nframes);
 503
 504                         if (this_nframes) {
 505
 506                                 click (_transport_sample, this_nframes);
 507
 508                                 if (process_routes (this_nframes, session_needs_butler)) {
 509                                         fail_roll (nframes);
 510                                         return;
 511                                 }
 512
 513                                 get_track_statistics ();
 514
 515                                 nframes -= this_nframes;
 516
 517                                 if (samples_moved < 0) {
 518                                         decrement_transport_position (-samples_moved);
 519                                 } else if (samples_moved) {
 520                                         increment_transport_position (samples_moved);
 521                                 }
 522
 523                                 maybe_stop (stop_limit);
 524                                 check_declick_out ();
 525                         }
 526
 527                         if (nframes > 0) {
 528                                 _engine.split_cycle (this_nframes);
 529                         }
 530
 531                         /* now handle this event and all others scheduled for the same time */
 532
 533                         while (this_event && this_event->action_sample == _transport_sample) {
 534                                 process_event (this_event);
 535
 536                                 if (the_next_one == events.end()) {
 537                                         this_event = 0;
 538                                 } else {
 539                                         this_event = *the_next_one;
 540                                         ++the_next_one;
 541                                 }
 542                         }
 543
 544                         /* if an event left our state changing, do the right thing */
 545
 546                         if (nframes && non_realtime_work_pending()) {
 547                                 no_roll (nframes);
 548                                 break;
 549                         }
 550
 551                         /* this is necessary to handle the case of seamless looping */
 552                         end_sample = _transport_sample + floor (nframes * _transport_speed);
 553                 }
 554
 555                 set_next_event ();
 556
 557         } /* implicit release of route lock */
 558
 559         if (session_needs_butler) {
 560                 DEBUG_TRACE (DEBUG::Butler, "p-with-events: session needs butler, call it\n");
 561                 _butler->summon ();
 562         }
 563 }
 564
 565 void
 566 Session::reset_slave_state ()
 567 {
 568         average_slave_delta = 1800;
 569         delta_accumulator_cnt = 0;
 570         have_first_delta_accumulator = false;
 571         _slave_state = Stopped;
 572         DiskReader::set_no_disk_output (false);
 573 }
 574
 575 bool
 576 Session::transport_locked () const
 577 {
 578         Slave* sl = _slave;
 579
 580         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 581                 return true;
 582         }
 583
 584         return false;
 585 }
 586
 587 bool
 588 Session::follow_slave (pframes_t nframes)
 589 {
 590         double slave_speed;
 591         samplepos_t slave_transport_sample;
 592         samplecnt_t this_delta;
 593         int dir;
 594
 595         if (!_slave->ok()) {
 596                 stop_transport ();
 597                 config.set_external_sync (false);
 598                 goto noroll;
 599         }
 600
 601         _slave->speed_and_position (slave_speed, slave_transport_sample);
 602
 603         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_sample, slave_speed));
 604
 605         if (!_slave->locked()) {
 606                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 607                 goto noroll;
 608         }
 609
 610         if (slave_transport_sample > _transport_sample) {
 611                 this_delta = slave_transport_sample - _transport_sample;
 612                 dir = 1;
 613         } else {
 614                 this_delta = _transport_sample - slave_transport_sample;
 615                 dir = -1;
 616         }
 617
 618         if (_slave->starting()) {
 619                 slave_speed = 0.0f;
 620         }
 621
 622         if (_slave->is_always_synced() ||
 623                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 624                         ) {
 625
 626                 /* if the TC source is synced, then we assume that its
 627                    speed is binary: 0.0 or 1.0
 628                 */
 629
 630                 if (slave_speed != 0.0f) {
 631                         slave_speed = 1.0f;
 632                 }
 633
 634         } else {
 635
 636                 /* if we are chasing and the average delta between us and the
 637                    master gets too big, we want to switch to silent
 638                    motion. so keep track of that here.
 639                 */
 640
 641                 if (_slave_state == Running) {
 642                         calculate_moving_average_of_slave_delta(dir, abs(this_delta));
 643                 }
 644         }
 645
 646         track_slave_state (slave_speed, slave_transport_sample, this_delta);
 647
 648         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 649                                                    _slave_state, slave_transport_sample, slave_speed, this_delta, average_slave_delta));
 650
 651
 652         if (_slave_state == Running && !_slave->is_always_synced() && !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)) {
 653
 654                 /* may need to varispeed to sync with slave */
 655
 656                 if (_transport_speed != 0.0f) {
 657
 658                         /*
 659                            note that average_dir is +1 or -1
 660                         */
 661
 662                         float delta;
 663
 664                         if (average_slave_delta == 0) {
 665                                 delta = this_delta;
 666                                 delta *= dir;
 667                         } else {
 668                                 delta = average_slave_delta;
 669                                 delta *= average_dir;
 670                         }
 671
 672 #ifndef NDEBUG
 673                         if (slave_speed != 0.0) {
 674                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 675                                                                            (int) (dir * this_delta),
 676                                                                            slave_speed,
 677                                                                            _transport_speed,
 678                                                                            _transport_sample,
 679                                                                            slave_transport_sample,
 680                                                                            average_slave_delta));
 681                         }
 682 #endif
 683
 684                         if (_slave->give_slave_full_control_over_transport_speed()) {
 685                                 set_transport_speed (slave_speed, 0, false, false);
 686                                 //std::cout << "set speed = " << slave_speed << "\n";
 687                         } else {
 688                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_sample_rate)));
 689                                 request_transport_speed (adjusted_speed);
 690                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 691                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 692                                                                            slave_speed));
 693                         }
 694
 695                         if (!actively_recording() && (samplecnt_t) average_slave_delta > _slave->resolution()) {
 696                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("average slave delta %1 greater than slave resolution %2 => no disk output\n", average_slave_delta, _slave->resolution()));
 697                                 /* run routes as normal, but no disk output */
 698                                 DiskReader::set_no_disk_output (true);
 699                                 return true;
 700                         }
 701
 702                         if (!have_first_delta_accumulator) {
 703                                 DEBUG_TRACE (DEBUG::Slave, "waiting for first slave delta accumulator to be ready, no disk output\n");
 704                                 /* run routes as normal, but no disk output */
 705                                 DiskReader::set_no_disk_output (true);
 706                                 return true;
 707                         }
 708                 }
 709         }
 710
 711
 712         if (!have_first_delta_accumulator) {
 713                 DEBUG_TRACE (DEBUG::Slave, "still waiting to compute slave delta, no disk output\n");
 714                 DiskReader::set_no_disk_output (true);
 715         } else {
 716                 DiskReader::set_no_disk_output (false);
 717         }
 718
 719         if ((_slave_state == Running) && (0 == (post_transport_work () & ~PostTransportSpeed))) {
 720                 /* speed is set, we're locked, and good to go */
 721                 return true;
 722         }
 723
 724   noroll:
 725         /* don't move at all */
 726         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 727         no_roll (nframes);
 728         return false;
 729 }
 730
 731 void
 732 Session::calculate_moving_average_of_slave_delta (int dir, samplecnt_t this_delta)
 733 {
 734         if (delta_accumulator_cnt >= delta_accumulator_size) {
 735                 have_first_delta_accumulator = true;
 736                 delta_accumulator_cnt = 0;
 737         }
 738
 739         if (delta_accumulator_cnt != 0 || this_delta < _current_sample_rate) {
 740                 delta_accumulator[delta_accumulator_cnt++] = (samplecnt_t) dir *  (samplecnt_t) this_delta;
 741         }
 742
 743         if (have_first_delta_accumulator) {
 744                 average_slave_delta = 0L;
 745                 for (int i = 0; i < delta_accumulator_size; ++i) {
 746                         average_slave_delta += delta_accumulator[i];
 747                 }
 748                 average_slave_delta /= (int32_t) delta_accumulator_size;
 749                 if (average_slave_delta < 0L) {
 750                         average_dir = -1;
 751                         average_slave_delta = average_slave_delta;
 752                 } else {
 753                         average_dir = 1;
 754                 }
 755         }
 756 }
 757
 758 void
 759 Session::track_slave_state (float slave_speed, samplepos_t slave_transport_sample, samplecnt_t /*this_delta*/)
 760 {
 761         if (slave_speed != 0.0f) {
 762
 763                 /* slave is running */
 764
 765                 switch (_slave_state) {
 766                 case Stopped:
 767                         if (_slave->requires_seekahead()) {
 768                                 slave_wait_end = slave_transport_sample + _slave->seekahead_distance ();
 769                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 770                                 /* we can call locate() here because we are in process context */
 771                                 locate (slave_wait_end, false, false);
 772                                 _slave_state = Waiting;
 773
 774                         } else {
 775
 776                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_sample));
 777
 778                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 779                                 average_slave_delta = 0L;
 780
 781                                 Location* al = _locations->auto_loop_location();
 782
 783                                 if (al && play_loop && (slave_transport_sample < al->start() || slave_transport_sample > al->end())) {
 784                                         // cancel looping
 785                                         request_play_loop(false);
 786                                 }
 787
 788                                 if (slave_transport_sample != _transport_sample) {
 789                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_sample, slave_transport_sample));
 790                                         locate (slave_transport_sample, false, false);
 791                                 }
 792                                 _slave_state = Running;
 793                         }
 794                         break;
 795
 796                 case Waiting:
 797                 default:
 798                         break;
 799                 }
 800
 801                 if (_slave_state == Waiting) {
 802
 803                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_sample));
 804
 805                         if (slave_transport_sample >= slave_wait_end) {
 806
 807                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_sample, _transport_sample));
 808
 809                                 _slave_state = Running;
 810
 811                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 812                                    precisely with the master.
 813                                 */
 814
 815
 816                                 bool ok = true;
 817                                 samplecnt_t sample_delta = slave_transport_sample - _transport_sample;
 818
 819                                 boost::shared_ptr<RouteList> rl = routes.reader();
 820                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 821                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 822                                         if (tr && !tr->can_internal_playback_seek (sample_delta)) {
 823                                                 ok = false;
 824                                                 break;
 825                                         }
 826                                 }
 827
 828                                 if (ok) {
 829                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 830                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 831                                                 if (tr) {
 832                                                         tr->internal_playback_seek (sample_delta);
 833                                                 }
 834                                         }
 835                                         _transport_sample += sample_delta;
 836
 837                                 } else {
 838                                         cerr << "cannot micro-seek\n";
 839                                         /* XXX what? */
 840                                 }
 841                         }
 842                 }
 843
 844                 if (_slave_state == Running && _transport_speed == 0.0f) {
 845                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 846                         start_transport ();
 847                 }
 848
 849         } else { // slave_speed is 0
 850
 851                 /* slave has stopped */
 852
 853                 if (_transport_speed != 0.0f) {
 854                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 sample %2 tf %3\n", slave_speed, slave_transport_sample, _transport_sample));
 855                         stop_transport ();
 856                 }
 857
 858                 if (slave_transport_sample != _transport_sample) {
 859                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_sample));
 860                         force_locate (slave_transport_sample, false);
 861                 }
 862
 863                 reset_slave_state();
 864         }
 865 }
 866
 867 void
 868 Session::process_without_events (pframes_t nframes)
 869 {
 870         bool session_needs_butler = false;
 871         samplecnt_t samples_moved;
 872
 873         if (!process_can_proceed()) {
 874                 _silent = true;
 875                 return;
 876         }
 877
 878         if (!_exporting && _slave) {
 879                 if (!follow_slave (nframes)) {
 880                         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample, 0, 0 , nframes);
 881                         return;
 882                 }
 883         }
 884
 885         if (_transport_speed == 0) {
 886                 no_roll (nframes);
 887                 return;
 888         }
 889
 890         if (_transport_speed == 1.0) {
 891                 samples_moved = (samplecnt_t) nframes;
 892         } else {
 893                 interpolation.set_speed (_transport_speed);
 894                 samples_moved = interpolation.distance (nframes);
 895         }
 896
 897         if (!_exporting && !timecode_transmission_suspended()) {
 898                 send_midi_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, nframes);
 899         }
 900
 901         ltc_tx_send_time_code_for_cycle (_transport_sample, _transport_sample + samples_moved, _target_transport_speed, _transport_speed, nframes);
 902
 903         samplepos_t const stop_limit = compute_stop_limit ();
 904
 905         if (maybe_stop (stop_limit)) {
 906                 no_roll (nframes);
 907                 return;
 908         }
 909
 910         if (maybe_sync_start (nframes)) {
 911                 return;
 912         }
 913
 914         click (_transport_sample, nframes);
 915
 916         if (process_routes (nframes, session_needs_butler)) {
 917                 fail_roll (nframes);
 918                 return;
 919         }
 920
 921         get_track_statistics ();
 922
 923         if (samples_moved < 0) {
 924                 decrement_transport_position (-samples_moved);
 925         } else if (samples_moved) {
 926                 increment_transport_position (samples_moved);
 927         }
 928
 929         maybe_stop (stop_limit);
 930         check_declick_out ();
 931
 932         if (session_needs_butler) {
 933                 DEBUG_TRACE (DEBUG::Butler, "p-without-events: session needs butler, call it\n");
 934                 _butler->summon ();
 935         }
 936 }
 937
 938 /** Process callback used when the auditioner is active.
 939  * @param nframes number of samples to process.
 940  */
 941 void
 942 Session::process_audition (pframes_t nframes)
 943 {
 944         SessionEvent* ev;
 945         boost::shared_ptr<RouteList> r = routes.reader ();
 946
 947         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 948                 if (!(*i)->is_auditioner()) {
 949                         (*i)->silence (nframes);
 950                 }
 951         }
 952
 953         /* run the auditioner, and if it says we need butler service, ask for it */
 954
 955         if (auditioner->play_audition (nframes) > 0) {
 956                 DEBUG_TRACE (DEBUG::Butler, "auditioner needs butler, call it\n");
 957                 _butler->summon ();
 958         }
 959
 960         /* if using a monitor section, run it because otherwise we don't hear anything */
 961
 962         if (_monitor_out && auditioner->needs_monitor()) {
 963                 _monitor_out->monitor_run (_transport_sample, _transport_sample + nframes, nframes, false);
 964         }
 965
 966         /* handle pending events */
 967
 968         while (pending_events.read (&ev, 1) == 1) {
 969                 merge_event (ev);
 970         }
 971
 972         /* if we are not in the middle of a state change,
 973            and there are immediate events queued up,
 974            process them.
 975         */
 976
 977         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 978                 SessionEvent *ev = immediate_events.front ();
 979                 immediate_events.pop_front ();
 980                 process_event (ev);
 981         }
 982
 983         if (!auditioner->auditioning()) {
 984                 /* auditioner no longer active, so go back to the normal process callback */
 985                 process_function = &Session::process_with_events;
 986         }
 987 }
 988
 989 bool
 990 Session::maybe_sync_start (pframes_t & nframes)
 991 {
 992         pframes_t sync_offset;
 993
 994         if (!waiting_for_sync_offset) {
 995                 return false;
 996         }
 997
 998         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 999
1000                 /* generate silence up to the sync point, then
1001                    adjust nframes + offset to reflect whatever
1002                    is left to do.
1003                 */
1004
1005                 no_roll (sync_offset);
1006                 nframes -= sync_offset;
1007                 Port::increment_global_port_buffer_offset (sync_offset);
1008                 waiting_for_sync_offset = false;
1009
1010                 if (nframes == 0) {
1011                         return true; // done, nothing left to process
1012                 }
1013
1014         } else {
1015
1016                 /* sync offset point is not within this process()
1017                    cycle, so just generate silence. and don't bother
1018                    with any fancy stuff here, just the minimal silence.
1019                 */
1020
1021                 _silent = true;
1022
1023                 if (Config->get_locate_while_waiting_for_sync()) {
1024                         if (micro_locate (nframes)) {
1025                                 /* XXX ERROR !!! XXX */
1026                         }
1027                 }
1028
1029                 return true; // done, nothing left to process
1030         }
1031
1032         return false;
1033 }
1034
1035 void
1036 Session::queue_event (SessionEvent* ev)
1037 {
1038         if (_state_of_the_state & Deletion) {
1039                 return;
1040         } else if (_state_of_the_state & Loading) {
1041                 merge_event (ev);
1042         } else {
1043                 Glib::Threads::Mutex::Lock lm (rb_write_lock);
1044                 pending_events.write (&ev, 1);
1045         }
1046 }
1047
1048 void
1049 Session::set_next_event ()
1050 {
1051         if (events.empty()) {
1052                 next_event = events.end();
1053                 return;
1054         }
1055
1056         if (next_event == events.end()) {
1057                 next_event = events.begin();
1058         }
1059
1060         if ((*next_event)->action_sample > _transport_sample) {
1061                 next_event = events.begin();
1062         }
1063
1064         for (; next_event != events.end(); ++next_event) {
1065                 if ((*next_event)->action_sample >= _transport_sample) {
1066                         break;
1067                 }
1068         }
1069 }
1070
1071 void
1072 Session::process_event (SessionEvent* ev)
1073 {
1074         bool remove = true;
1075         bool del = true;
1076
1077         /* if we're in the middle of a state change (i.e. waiting
1078            for the butler thread to complete the non-realtime
1079            part of the change), we'll just have to queue this
1080            event for a time when the change is complete.
1081         */
1082
1083         if (non_realtime_work_pending()) {
1084
1085                 /* except locates, which we have the capability to handle */
1086
1087                 if (ev->type != SessionEvent::Locate) {
1088                         immediate_events.insert (immediate_events.end(), ev);
1089                         _remove_event (ev);
1090                         return;
1091                 }
1092         }
1093
1094         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_sample));
1095
1096         switch (ev->type) {
1097         case SessionEvent::SetLoop:
1098                 set_play_loop (ev->yes_or_no, ev->speed);
1099                 break;
1100
1101         case SessionEvent::AutoLoop:
1102                 if (play_loop) {
1103                         /* roll after locate, do not flush, set "with loop"
1104                            true only if we are seamless looping
1105                         */
1106                         start_locate (ev->target_sample, true, false, Config->get_seamless_loop());
1107                 }
1108                 remove = false;
1109                 del = false;
1110                 break;
1111
1112         case SessionEvent::AutoLoopDeclick:
1113                 if (play_loop) {
1114                         /* Request a declick fade-out and a fade-in; the fade-out will happen
1115                            at the end of the loop, and the fade-in at the start.
1116                         */
1117                         transport_sub_state |= (PendingLoopDeclickOut | PendingLoopDeclickIn);
1118                 }
1119                 remove = false;
1120                 del = false;
1121                 break;
1122
1123         case SessionEvent::Locate:
1124                 if (ev->yes_or_no) { /* force locate */
1125                         /* args: do not roll after locate, do flush, not with loop */
1126                         locate (ev->target_sample, false, true, false);
1127                 } else {
1128                         /* args: do not roll after locate, do flush, not with loop */
1129                         start_locate (ev->target_sample, false, true, false);
1130                 }
1131                 _send_timecode_update = true;
1132                 break;
1133
1134         case SessionEvent::LocateRoll:
1135                 if (ev->yes_or_no) {
1136                         /* args: roll after locate, do flush, not with loop */
1137                         locate (ev->target_sample, true, true, false);
1138                 } else {
1139                         /* args: roll after locate, do flush, not with loop */
1140                         start_locate (ev->target_sample, true, true, false);
1141                 }
1142                 _send_timecode_update = true;
1143                 break;
1144
1145         case SessionEvent::Skip:
1146                 if (Config->get_skip_playback()) {
1147                         start_locate (ev->target_sample, true, true, false);
1148                         _send_timecode_update = true;
1149                 }
1150                 remove = false;
1151                 del = false;
1152                 break;
1153
1154         case SessionEvent::LocateRollLocate:
1155                 // locate is handled by ::request_roll_at_and_return()
1156                 _requested_return_sample = ev->target_sample;
1157                 request_locate (ev->target2_sample, true);
1158                 break;
1159
1160
1161         case SessionEvent::SetTransportSpeed:
1162                 set_transport_speed (ev->speed, ev->target_sample, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1163                 break;
1164
1165         case SessionEvent::PunchIn:
1166                 // cerr << "PunchIN at " << transport_sample() << endl;
1167                 if (config.get_punch_in() && record_status() == Enabled) {
1168                         enable_record ();
1169                 }
1170                 remove = false;
1171                 del = false;
1172                 break;
1173
1174         case SessionEvent::PunchOut:
1175                 // cerr << "PunchOUT at " << transport_sample() << endl;
1176                 if (config.get_punch_out()) {
1177                         step_back_from_record ();
1178                 }
1179                 remove = false;
1180                 del = false;
1181                 break;
1182
1183         case SessionEvent::StopOnce:
1184                 if (!non_realtime_work_pending()) {
1185                         _clear_event_type (SessionEvent::StopOnce);
1186                         stop_transport (ev->yes_or_no);
1187                 }
1188                 remove = false;
1189                 del = false;
1190                 break;
1191
1192         case SessionEvent::RangeStop:
1193                 if (!non_realtime_work_pending()) {
1194                         stop_transport (ev->yes_or_no);
1195                 }
1196                 remove = false;
1197                 del = false;
1198                 break;
1199
1200         case SessionEvent::RangeLocate:
1201                 /* args: roll after locate, do flush, not with loop */
1202                 start_locate (ev->target_sample, true, true, false);
1203                 remove = false;
1204                 del = false;
1205                 break;
1206
1207         case SessionEvent::Overwrite:
1208                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1209                 break;
1210
1211         case SessionEvent::SetSyncSource:
1212                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1213                 use_sync_source (ev->slave);
1214                 break;
1215
1216         case SessionEvent::Audition:
1217                 set_audition (ev->region);
1218                 // drop reference to region
1219                 ev->region.reset ();
1220                 break;
1221
1222         case SessionEvent::SetPlayAudioRange:
1223                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1224                 break;
1225
1226         case SessionEvent::CancelPlayAudioRange:
1227                 unset_play_range();
1228                 break;
1229
1230         case SessionEvent::RealTimeOperation:
1231                 process_rtop (ev);
1232                 del = false; // other side of RT request needs to clean up
1233                 break;
1234
1235         case SessionEvent::AdjustPlaybackBuffering:
1236                 schedule_playback_buffering_adjustment ();
1237                 break;
1238
1239         case SessionEvent::AdjustCaptureBuffering:
1240                 schedule_capture_buffering_adjustment ();
1241                 break;
1242
1243         case SessionEvent::SetTimecodeTransmission:
1244                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1245                 break;
1246
1247         default:
1248           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1249                 abort(); /*NOTREACHED*/
1250                 break;
1251         };
1252
1253         if (remove) {
1254                 del = del && !_remove_event (ev);
1255         }
1256
1257         if (del) {
1258                 delete ev;
1259         }
1260 }
1261
1262 samplepos_t
1263 Session::compute_stop_limit () const
1264 {
1265         if (!Config->get_stop_at_session_end ()) {
1266                 return max_samplepos;
1267         }
1268
1269         if (_slave) {
1270                 return max_samplepos;
1271         }
1272
1273         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1274         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1275
1276         if (actively_recording ()) {
1277                 /* permanently recording */
1278                 return max_samplepos;
1279         } else if (punching_in && !punching_out) {
1280                 /* punching in but never out */
1281                 return max_samplepos;
1282         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_sample()) {
1283                 /* punching in and punching out after session end */
1284                 return max_samplepos;
1285         }
1286
1287         return current_end_sample ();
1288 }
1289
1290
1291
1292 /* dedicated thread for signal emission.
1293  *
1294  * while sending cross-thread signals from the process thread
1295  * is fine in general, PBD::Signal's use of boost::function and
1296  * boost:bind can produce a vast overhead which is not
1297  * acceptable for low latency.
1298  *
1299  * This works around the issue by moving the boost overhead
1300  * out of the RT thread. The overall load is probably higher but
1301  * the realtime thread remains unaffected.
1302  */
1303
1304 void
1305 Session::emit_route_signals ()
1306 {
1307         // TODO use RAII to allow using these signals in other places
1308         BatchUpdateStart(); /* EMIT SIGNAL */
1309         boost::shared_ptr<RouteList> r = routes.reader ();
1310         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1311                 (*ci)->emit_pending_signals ();
1312         }
1313         BatchUpdateEnd(); /* EMIT SIGNAL */
1314 }
1315
1316 void
1317 Session::emit_thread_start ()
1318 {
1319         if (_rt_thread_active) {
1320                 return;
1321         }
1322         _rt_thread_active = true;
1323
1324         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1325                 _rt_thread_active = false;
1326         }
1327 }
1328
1329 void
1330 Session::emit_thread_terminate ()
1331 {
1332         if (!_rt_thread_active) {
1333                 return;
1334         }
1335         _rt_thread_active = false;
1336
1337         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1338                 pthread_cond_signal (&_rt_emit_cond);
1339                 pthread_mutex_unlock (&_rt_emit_mutex);
1340         }
1341
1342         void *status;
1343         pthread_join (_rt_emit_thread, &status);
1344 }
1345
1346 void *
1347 Session::emit_thread (void *arg)
1348 {
1349         Session *s = static_cast<Session *>(arg);
1350         s->emit_thread_run ();
1351         pthread_exit (0);
1352         return 0;
1353 }
1354
1355 void
1356 Session::emit_thread_run ()
1357 {
1358         pthread_mutex_lock (&_rt_emit_mutex);
1359         while (_rt_thread_active) {
1360                 emit_route_signals();
1361                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1362         }
1363         pthread_mutex_unlock (&_rt_emit_mutex);
1364 }