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/graph.h"
  36 #include "ardour/port.h"
  37 #include "ardour/process_thread.h"
  38 #include "ardour/scene_changer.h"
  39 #include "ardour/session.h"
  40 #include "ardour/slave.h"
  41 #include "ardour/ticker.h"
  42 #include "ardour/types.h"
  43 #include "ardour/vca.h"
  44 #include "ardour/vca_manager.h"
  45
  46 #include "midi++/mmc.h"
  47
  48 #include "pbd/i18n.h"
  49
  50 using namespace ARDOUR;
  51 using namespace PBD;
  52 using namespace std;
  53
  54 /** Called by the audio engine when there is work to be done with JACK.
  55  * @param nframes Number of frames to process.
  56  */
  57
  58 void
  59 Session::process (pframes_t nframes)
  60 {
  61         framepos_t transport_at_start = _transport_frame;
  62
  63         _silent = false;
  64
  65         if (processing_blocked()) {
  66                 _silent = true;
  67                 return;
  68         }
  69
  70         if (non_realtime_work_pending()) {
  71                 if (!_butler->transport_work_requested ()) {
  72                         post_transport ();
  73                 }
  74         }
  75
  76         _engine.main_thread()->get_buffers ();
  77
  78         (this->*process_function) (nframes);
  79
  80         /* realtime-safe meter-position and processor-order changes
  81          *
  82          * ideally this would be done in
  83          * Route::process_output_buffers() but various functions
  84          * callig it hold a _processor_lock reader-lock
  85          */
  86         boost::shared_ptr<RouteList> r = routes.reader ();
  87         for (RouteList::const_iterator i = r->begin(); i != r->end(); ++i) {
  88                 if ((*i)->apply_processor_changes_rt()) {
  89                         _rt_emit_pending = true;
  90                 }
  91         }
  92         if (_rt_emit_pending) {
  93                 if (!_rt_thread_active) {
  94                         emit_route_signals ();
  95                 }
  96                 if (pthread_mutex_trylock (&_rt_emit_mutex) == 0) {
  97                         pthread_cond_signal (&_rt_emit_cond);
  98                         pthread_mutex_unlock (&_rt_emit_mutex);
  99                         _rt_emit_pending = false;
 100                 }
 101         }
 102
 103         _engine.main_thread()->drop_buffers ();
 104
 105         /* deliver MIDI clock. Note that we need to use the transport frame
 106          * position at the start of process(), not the value at the end of
 107          * it. We may already have ticked() because of a transport state
 108          * change, for example.
 109          */
 110
 111         try {
 112                 if (!_silent && !_engine.freewheeling() && Config->get_send_midi_clock() && (transport_speed() == 1.0f || transport_speed() == 0.0f) && midi_clock->has_midi_port()) {
 113                         midi_clock->tick (transport_at_start, nframes);
 114                 }
 115
 116                 _scene_changer->run (transport_at_start, transport_at_start + nframes);
 117
 118         } catch (...) {
 119                 /* don't bother with a message */
 120         }
 121
 122         SendFeedback (); /* EMIT SIGNAL */
 123 }
 124
 125 int
 126 Session::fail_roll (pframes_t nframes)
 127 {
 128         return no_roll (nframes);
 129 }
 130
 131 int
 132 Session::no_roll (pframes_t nframes)
 133 {
 134         PT_TIMING_CHECK (4);
 135
 136         framepos_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 137         int ret = 0;
 138         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 139         boost::shared_ptr<RouteList> r = routes.reader ();
 140
 141         if (_click_io) {
 142                 _click_io->silence (nframes);
 143         }
 144
 145         ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 146
 147         VCAList v = _vca_manager->vcas ();
 148         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 149                 (*i)->automation_run (_transport_frame, nframes);
 150         }
 151
 152         if (_process_graph) {
 153                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 154                 _process_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), declick);
 155         } else {
 156                 PT_TIMING_CHECK (10);
 157                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 158
 159                         if ((*i)->is_auditioner()) {
 160                                 continue;
 161                         }
 162
 163                         (*i)->set_pending_declick (declick);
 164
 165                         if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending())) {
 166                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 167                                 ret = -1;
 168                                 break;
 169                         }
 170                 }
 171                 PT_TIMING_CHECK (11);
 172         }
 173
 174         PT_TIMING_CHECK (5);
 175         return ret;
 176 }
 177
 178 /** @param need_butler to be set to true by this method if it needs the butler,
 179  *  otherwise it must be left alone.
 180  */
 181 int
 182 Session::process_routes (pframes_t nframes, bool& need_butler)
 183 {
 184         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 185         boost::shared_ptr<RouteList> r = routes.reader ();
 186
 187         const framepos_t start_frame = _transport_frame;
 188         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 189
 190         VCAList v = _vca_manager->vcas ();
 191         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 192                 (*i)->automation_run (start_frame, nframes);
 193         }
 194
 195         if (_process_graph) {
 196                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 197                 if (_process_graph->process_routes (nframes, start_frame, end_frame, declick, need_butler) < 0) {
 198                         stop_transport ();
 199                         return -1;
 200                 }
 201         } else {
 202
 203                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 204
 205                         int ret;
 206
 207                         if ((*i)->is_auditioner()) {
 208                                 continue;
 209                         }
 210
 211                         (*i)->set_pending_declick (declick);
 212
 213                         bool b = false;
 214
 215                         if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, b)) < 0) {
 216                                 stop_transport ();
 217                                 return -1;
 218                         }
 219
 220                         if (b) {
 221                                 DEBUG_TRACE (DEBUG::Butler, string_compose ("%1 rolled and needs butler\n", (*i)->name()));
 222                                 need_butler = true;
 223                         }
 224                 }
 225         }
 226
 227         return 0;
 228 }
 229
 230 /** @param need_butler to be set to true by this method if it needs the butler,
 231  *  otherwise it must be left alone.
 232  */
 233 int
 234 Session::silent_process_routes (pframes_t nframes, bool& need_butler)
 235 {
 236         boost::shared_ptr<RouteList> r = routes.reader ();
 237
 238         const framepos_t start_frame = _transport_frame;
 239         const framepos_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 240
 241         VCAList v = _vca_manager->vcas ();
 242         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 243                 (*i)->automation_run (start_frame, nframes);
 244         }
 245
 246         if (_process_graph) {
 247                 _process_graph->silent_process_routes (nframes, start_frame, end_frame, need_butler);
 248         } else {
 249                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 250
 251                         int ret;
 252
 253                         if ((*i)->is_auditioner()) {
 254                                 continue;
 255                         }
 256
 257                         bool b = false;
 258
 259                         if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, b)) < 0) {
 260                                 stop_transport ();
 261                                 return -1;
 262                         }
 263
 264                         if (b) {
 265                                 need_butler = true;
 266                         }
 267                 }
 268         }
 269
 270         return 0;
 271 }
 272
 273 void
 274 Session::get_track_statistics ()
 275 {
 276         float pworst = 1.0f;
 277         float cworst = 1.0f;
 278
 279         boost::shared_ptr<RouteList> rl = routes.reader();
 280         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 281
 282                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 283
 284                 if (!tr || tr->hidden()) {
 285                         continue;
 286                 }
 287
 288                 pworst = min (pworst, tr->playback_buffer_load());
 289                 cworst = min (cworst, tr->capture_buffer_load());
 290         }
 291
 292         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 293         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 294
 295         if (actively_recording()) {
 296                 set_dirty();
 297         }
 298 }
 299
 300 /** Process callback used when the auditioner is not active */
 301 void
 302 Session::process_with_events (pframes_t nframes)
 303 {
 304         PT_TIMING_CHECK (3);
 305
 306         SessionEvent*  ev;
 307         pframes_t      this_nframes;
 308         framepos_t     end_frame;
 309         bool           session_needs_butler = false;
 310         framecnt_t     frames_moved;
 311
 312         /* make sure the auditioner is silent */
 313
 314         if (auditioner) {
 315                 auditioner->silence (nframes);
 316         }
 317
 318         /* handle any pending events */
 319
 320         while (pending_events.read (&ev, 1) == 1) {
 321                 merge_event (ev);
 322         }
 323
 324         /* if we are not in the middle of a state change,
 325            and there are immediate events queued up,
 326            process them.
 327         */
 328
 329         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 330                 SessionEvent *ev = immediate_events.front ();
 331                 immediate_events.pop_front ();
 332                 process_event (ev);
 333         }
 334
 335         /* count in */
 336         if (_transport_speed != 1.0 && _count_in_samples > 0) {
 337                 _count_in_samples = 0;
 338         }
 339
 340         if (_count_in_samples > 0) {
 341                 framecnt_t ns = std::min ((framecnt_t)nframes, _count_in_samples);
 342
 343                 no_roll (ns);
 344                 run_click (_transport_frame - _count_in_samples, ns);
 345
 346                 _count_in_samples -= ns;
 347                 nframes -= ns;
 348
 349                 /* process events.. */
 350                 if (!events.empty() && next_event != events.end()) {
 351                         SessionEvent* this_event = *next_event;
 352                         Events::iterator the_next_one = next_event;
 353                         ++the_next_one;
 354
 355                         while (this_event && this_event->action_frame == _transport_frame) {
 356                                 process_event (this_event);
 357                                 if (the_next_one == events.end()) {
 358                                         this_event = 0;
 359                                 } else {
 360                                         this_event = *the_next_one;
 361                                         ++the_next_one;
 362                                 }
 363                         }
 364                         set_next_event ();
 365                 }
 366
 367                 check_declick_out ();
 368
 369                 if (nframes == 0) {
 370                         return;
 371                 } else {
 372                         _engine.split_cycle (ns);
 373                 }
 374         }
 375
 376         /* Decide on what to do with quarter-frame MTC during this cycle */
 377
 378         bool const was_sending_qf_mtc = _send_qf_mtc;
 379         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 380
 381         if (_transport_speed != 0) {
 382                 _send_qf_mtc = (
 383                         Config->get_send_mtc () &&
 384                         _transport_speed >= (1 - tolerance) &&
 385                         _transport_speed <= (1 + tolerance)
 386                         );
 387
 388                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 389                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 390                         _send_timecode_update = true;
 391                 }
 392
 393                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (frame_rate () / 4)) {
 394                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 395                            a quarter of a second since we sent anything at all, so send a full MTC update
 396                            this cycle.
 397                         */
 398                         _send_timecode_update = true;
 399                 }
 400
 401                 _pframes_since_last_mtc += nframes;
 402         }
 403
 404         /* Events caused a transport change (or we re-started sending
 405          * MTC), so send an MTC Full Frame (Timecode) message.  This
 406          * is sent whether rolling or not, to give slaves an idea of
 407          * ardour time on locates (and allow slow slaves to position
 408          * and prepare for rolling)
 409          */
 410         if (_send_timecode_update) {
 411                 send_full_time_code (_transport_frame, nframes);
 412         }
 413
 414         if (!process_can_proceed()) {
 415                 _silent = true;
 416                 return;
 417         }
 418
 419         if (events.empty() || next_event == events.end()) {
 420                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 421                 /* lua scripts may inject events */
 422                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 423                         merge_event (ev);
 424                 }
 425                 if (events.empty() || next_event == events.end()) {
 426                         process_without_events (nframes);
 427                         return;
 428                 }
 429         }
 430
 431         if (locate_pending()) {
 432                 frames_moved = 0;
 433         } else {
 434                 if (_transport_speed == 1.0) {
 435                         frames_moved = (framecnt_t) nframes;
 436                 } else {
 437                         interpolation.set_target_speed (_target_transport_speed);
 438                         interpolation.set_speed (_transport_speed);
 439                         frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 440                 }
 441         }
 442
 443         end_frame = _transport_frame + frames_moved;
 444
 445         {
 446                 SessionEvent* this_event;
 447                 Events::iterator the_next_one;
 448
 449                 if (!process_can_proceed()) {
 450                         _silent = true;
 451                         return;
 452                 }
 453
 454                 if (!_exporting && _slave) {
 455                         if (!follow_slave (nframes)) {
 456                                 return;
 457                         }
 458                 }
 459
 460                 if (_transport_speed == 0) {
 461                         no_roll (nframes);
 462                         return;
 463                 }
 464
 465                 if (!_exporting && !timecode_transmission_suspended()) {
 466                         send_midi_time_code_for_cycle (_transport_frame, end_frame, nframes);
 467                 }
 468
 469                 ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 470
 471                 framepos_t stop_limit = compute_stop_limit ();
 472
 473                 if (maybe_stop (stop_limit)) {
 474                         no_roll (nframes);
 475                         return;
 476                 }
 477
 478                 this_event = *next_event;
 479                 the_next_one = next_event;
 480                 ++the_next_one;
 481
 482                 /* yes folks, here it is, the actual loop where we really truly
 483                    process some audio
 484                 */
 485
 486                 while (nframes) {
 487
 488                         this_nframes = nframes; /* real (jack) time relative */
 489                         if (locate_pending()) {
 490                                 frames_moved = 0;
 491                         } else {
 492                                 frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 493                         }
 494
 495                         /* running an event, position transport precisely to its time */
 496                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 497                                 /* this isn't quite right for reverse play */
 498                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 499                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 500                         }
 501
 502                         try_run_lua (this_nframes);
 503
 504                         if (this_nframes) {
 505
 506                                 click (_transport_frame, 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 (frames_moved < 0) {
 518                                         decrement_transport_position (-frames_moved);
 519                                 } else if (frames_moved) {
 520                                         increment_transport_position (frames_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_frame == _transport_frame) {
 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_frame = _transport_frame + 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 }
 573
 574 bool
 575 Session::transport_locked () const
 576 {
 577         Slave* sl = _slave;
 578
 579         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 580                 return true;
 581         }
 582
 583         return false;
 584 }
 585
 586 bool
 587 Session::follow_slave (pframes_t nframes)
 588 {
 589         double slave_speed;
 590         framepos_t slave_transport_frame;
 591         framecnt_t this_delta;
 592         int dir;
 593
 594         if (!_slave->ok()) {
 595                 stop_transport ();
 596                 config.set_external_sync (false);
 597                 goto noroll;
 598         }
 599
 600         _slave->speed_and_position (slave_speed, slave_transport_frame);
 601
 602         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 603
 604         if (!_slave->locked()) {
 605                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 606                 goto noroll;
 607         }
 608
 609         if (slave_transport_frame > _transport_frame) {
 610                 this_delta = slave_transport_frame - _transport_frame;
 611                 dir = 1;
 612         } else {
 613                 this_delta = _transport_frame - slave_transport_frame;
 614                 dir = -1;
 615         }
 616
 617         if (_slave->starting()) {
 618                 slave_speed = 0.0f;
 619         }
 620
 621         if (_slave->is_always_synced() ||
 622                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 623                         ) {
 624
 625                 /* if the TC source is synced, then we assume that its
 626                    speed is binary: 0.0 or 1.0
 627                 */
 628
 629                 if (slave_speed != 0.0f) {
 630                         slave_speed = 1.0f;
 631                 }
 632
 633         } else {
 634
 635                 /* if we are chasing and the average delta between us and the
 636                    master gets too big, we want to switch to silent
 637                    motion. so keep track of that here.
 638                 */
 639
 640                 if (_slave_state == Running) {
 641                         calculate_moving_average_of_slave_delta(dir, this_delta);
 642                 }
 643         }
 644
 645         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 646
 647         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 648                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 649
 650
 651         if (_slave_state == Running && !_slave->is_always_synced() &&
 652                         !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 653                         ) {
 654
 655                 if (_transport_speed != 0.0f) {
 656
 657                         /*
 658                            note that average_dir is +1 or -1
 659                         */
 660
 661                         float delta;
 662
 663                         if (average_slave_delta == 0) {
 664                                 delta = this_delta;
 665                                 delta *= dir;
 666                         } else {
 667                                 delta = average_slave_delta;
 668                                 delta *= average_dir;
 669                         }
 670
 671 #ifndef NDEBUG
 672                         if (slave_speed != 0.0) {
 673                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 674                                                                            (int) (dir * this_delta),
 675                                                                            slave_speed,
 676                                                                            _transport_speed,
 677                                                                            _transport_frame,
 678                                                                            slave_transport_frame,
 679                                                                            average_slave_delta));
 680                         }
 681 #endif
 682
 683                         if (_slave->give_slave_full_control_over_transport_speed()) {
 684                                 set_transport_speed (slave_speed, 0, false, false);
 685                                 //std::cout << "set speed = " << slave_speed << "\n";
 686                         } else {
 687                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 688                                 request_transport_speed (adjusted_speed);
 689                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 690                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 691                                                                            slave_speed));
 692                         }
 693
 694 #if 1
 695                         if (!actively_recording() && (framecnt_t) abs(average_slave_delta) > _slave->resolution()) {
 696                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 697                                 goto silent_motion;
 698                         }
 699 #endif
 700                 }
 701         }
 702
 703
 704         if (_slave_state == Running && 0 == (post_transport_work () & ~PostTransportSpeed)) {
 705                 /* speed is set, we're locked, and good to go */
 706                 return true;
 707         }
 708
 709   silent_motion:
 710         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 711         follow_slave_silently (nframes, slave_speed);
 712
 713   noroll:
 714         /* don't move at all */
 715         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 716         no_roll (nframes);
 717         return false;
 718 }
 719
 720 void
 721 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 722 {
 723         if (delta_accumulator_cnt >= delta_accumulator_size) {
 724                 have_first_delta_accumulator = true;
 725                 delta_accumulator_cnt = 0;
 726         }
 727
 728         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 729                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 730         }
 731
 732         if (have_first_delta_accumulator) {
 733                 average_slave_delta = 0L;
 734                 for (int i = 0; i < delta_accumulator_size; ++i) {
 735                         average_slave_delta += delta_accumulator[i];
 736                 }
 737                 average_slave_delta /= (int32_t) delta_accumulator_size;
 738                 if (average_slave_delta < 0L) {
 739                         average_dir = -1;
 740                         average_slave_delta = abs(average_slave_delta);
 741                 } else {
 742                         average_dir = 1;
 743                 }
 744         }
 745 }
 746
 747 void
 748 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t /*this_delta*/)
 749 {
 750         if (slave_speed != 0.0f) {
 751
 752                 /* slave is running */
 753
 754                 switch (_slave_state) {
 755                 case Stopped:
 756                         if (_slave->requires_seekahead()) {
 757                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 758                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 759                                 /* we can call locate() here because we are in process context */
 760                                 locate (slave_wait_end, false, false);
 761                                 _slave_state = Waiting;
 762
 763                         } else {
 764
 765                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_frame));
 766
 767                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 768                                 average_slave_delta = 0L;
 769
 770                                 Location* al = _locations->auto_loop_location();
 771
 772                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 773                                         // cancel looping
 774                                         request_play_loop(false);
 775                                 }
 776
 777                                 if (slave_transport_frame != _transport_frame) {
 778                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_frame, slave_transport_frame));
 779                                         locate (slave_transport_frame, false, false);
 780                                 }
 781                                 _slave_state = Running;
 782                         }
 783                         break;
 784
 785                 case Waiting:
 786                 default:
 787                         break;
 788                 }
 789
 790                 if (_slave_state == Waiting) {
 791
 792                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 793
 794                         if (slave_transport_frame >= slave_wait_end) {
 795
 796                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 797
 798                                 _slave_state = Running;
 799
 800                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 801                                    precisely with the master.
 802                                 */
 803
 804
 805                                 bool ok = true;
 806                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 807
 808                                 boost::shared_ptr<RouteList> rl = routes.reader();
 809                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 810                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 811                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 812                                                 ok = false;
 813                                                 break;
 814                                         }
 815                                 }
 816
 817                                 if (ok) {
 818                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 819                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 820                                                 if (tr) {
 821                                                         tr->internal_playback_seek (frame_delta);
 822                                                 }
 823                                         }
 824                                         _transport_frame += frame_delta;
 825
 826                                 } else {
 827                                         cerr << "cannot micro-seek\n";
 828                                         /* XXX what? */
 829                                 }
 830                         }
 831                 }
 832
 833                 if (_slave_state == Running && _transport_speed == 0.0f) {
 834                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 835                         start_transport ();
 836                 }
 837
 838         } else { // slave_speed is 0
 839
 840                 /* slave has stopped */
 841
 842                 if (_transport_speed != 0.0f) {
 843                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 844                         stop_transport ();
 845                 }
 846
 847                 if (slave_transport_frame != _transport_frame) {
 848                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 849                         force_locate (slave_transport_frame, false);
 850                 }
 851
 852                 reset_slave_state();
 853         }
 854 }
 855
 856 void
 857 Session::follow_slave_silently (pframes_t nframes, float slave_speed)
 858 {
 859         if (slave_speed && _transport_speed) {
 860
 861                 /* something isn't right, but we should move with the master
 862                    for now.
 863                 */
 864
 865                 bool need_butler = false;
 866
 867                 silent_process_routes (nframes, need_butler);
 868
 869                 get_track_statistics ();
 870
 871                 if (need_butler) {
 872                         DEBUG_TRACE (DEBUG::Butler, "f-slave-silently: session needs butler, call it\n");
 873                         _butler->summon ();
 874                 }
 875
 876                 int32_t frames_moved;
 877
 878                 if (locate_pending()) {
 879                         frames_moved = 0;
 880                 } else {
 881                         frames_moved = (int32_t) floor (_transport_speed * nframes);
 882                 }
 883
 884                 if (frames_moved < 0) {
 885                         decrement_transport_position (-frames_moved);
 886                 } else if (frames_moved) {
 887                         increment_transport_position (frames_moved);
 888                 }
 889
 890                 framepos_t const stop_limit = compute_stop_limit ();
 891                 maybe_stop (stop_limit);
 892         }
 893 }
 894
 895 void
 896 Session::process_without_events (pframes_t nframes)
 897 {
 898         bool session_needs_butler = false;
 899         framecnt_t frames_moved;
 900
 901         if (!process_can_proceed()) {
 902                 _silent = true;
 903                 return;
 904         }
 905
 906         if (!_exporting && _slave) {
 907                 if (!follow_slave (nframes)) {
 908                         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame, 0, 0 , nframes);
 909                         return;
 910                 }
 911         }
 912
 913         if (_transport_speed == 0) {
 914                 no_roll (nframes);
 915                 return;
 916         }
 917
 918         if (locate_pending()) {
 919                 frames_moved = 0;
 920         } else {
 921                 if (_transport_speed == 1.0) {
 922                         frames_moved = (framecnt_t) nframes;
 923                 } else {
 924                         interpolation.set_target_speed (_target_transport_speed);
 925                         interpolation.set_speed (_transport_speed);
 926                         frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 927                 }
 928         }
 929
 930         if (!_exporting && !timecode_transmission_suspended()) {
 931                 send_midi_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, nframes);
 932         }
 933
 934         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, _target_transport_speed, _transport_speed, nframes);
 935
 936         framepos_t const stop_limit = compute_stop_limit ();
 937
 938         if (maybe_stop (stop_limit)) {
 939                 no_roll (nframes);
 940                 return;
 941         }
 942
 943         if (maybe_sync_start (nframes)) {
 944                 return;
 945         }
 946
 947         click (_transport_frame, nframes);
 948
 949         if (process_routes (nframes, session_needs_butler)) {
 950                 fail_roll (nframes);
 951                 return;
 952         }
 953
 954         get_track_statistics ();
 955
 956         if (frames_moved < 0) {
 957                 decrement_transport_position (-frames_moved);
 958         } else if (frames_moved) {
 959                 increment_transport_position (frames_moved);
 960         }
 961
 962         maybe_stop (stop_limit);
 963         check_declick_out ();
 964
 965         if (session_needs_butler) {
 966                 DEBUG_TRACE (DEBUG::Butler, "p-without-events: session needs butler, call it\n");
 967                 _butler->summon ();
 968         }
 969 }
 970
 971 /** Process callback used when the auditioner is active.
 972  * @param nframes number of frames to process.
 973  */
 974 void
 975 Session::process_audition (pframes_t nframes)
 976 {
 977         SessionEvent* ev;
 978         boost::shared_ptr<RouteList> r = routes.reader ();
 979
 980         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 981                 if (!(*i)->is_auditioner()) {
 982                         (*i)->silence (nframes);
 983                 }
 984         }
 985
 986         /* run the auditioner, and if it says we need butler service, ask for it */
 987
 988         if (auditioner->play_audition (nframes) > 0) {
 989                 DEBUG_TRACE (DEBUG::Butler, "auditioner needs butler, call it\n");
 990                 _butler->summon ();
 991         }
 992
 993         /* if using a monitor section, run it because otherwise we don't hear anything */
 994
 995         if (_monitor_out && auditioner->needs_monitor()) {
 996                 _monitor_out->monitor_run (_transport_frame, _transport_frame + nframes, nframes, false);
 997         }
 998
 999         /* handle pending events */
1000
1001         while (pending_events.read (&ev, 1) == 1) {
1002                 merge_event (ev);
1003         }
1004
1005         /* if we are not in the middle of a state change,
1006            and there are immediate events queued up,
1007            process them.
1008         */
1009
1010         while (!non_realtime_work_pending() && !immediate_events.empty()) {
1011                 SessionEvent *ev = immediate_events.front ();
1012                 immediate_events.pop_front ();
1013                 process_event (ev);
1014         }
1015
1016         if (!auditioner->auditioning()) {
1017                 /* auditioner no longer active, so go back to the normal process callback */
1018                 process_function = &Session::process_with_events;
1019         }
1020 }
1021
1022 bool
1023 Session::maybe_sync_start (pframes_t & nframes)
1024 {
1025         pframes_t sync_offset;
1026
1027         if (!waiting_for_sync_offset) {
1028                 return false;
1029         }
1030
1031         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
1032
1033                 /* generate silence up to the sync point, then
1034                    adjust nframes + offset to reflect whatever
1035                    is left to do.
1036                 */
1037
1038                 no_roll (sync_offset);
1039                 nframes -= sync_offset;
1040                 Port::increment_global_port_buffer_offset (sync_offset);
1041                 waiting_for_sync_offset = false;
1042
1043                 if (nframes == 0) {
1044                         return true; // done, nothing left to process
1045                 }
1046
1047         } else {
1048
1049                 /* sync offset point is not within this process()
1050                    cycle, so just generate silence. and don't bother
1051                    with any fancy stuff here, just the minimal silence.
1052                 */
1053
1054                 _silent = true;
1055
1056                 if (Config->get_locate_while_waiting_for_sync()) {
1057                         if (micro_locate (nframes)) {
1058                                 /* XXX ERROR !!! XXX */
1059                         }
1060                 }
1061
1062                 return true; // done, nothing left to process
1063         }
1064
1065         return false;
1066 }
1067
1068 void
1069 Session::queue_event (SessionEvent* ev)
1070 {
1071         if (_state_of_the_state & Deletion) {
1072                 return;
1073         } else if (_state_of_the_state & Loading) {
1074                 merge_event (ev);
1075         } else {
1076                 Glib::Threads::Mutex::Lock lm (rb_write_lock);
1077                 pending_events.write (&ev, 1);
1078         }
1079 }
1080
1081 void
1082 Session::set_next_event ()
1083 {
1084         if (events.empty()) {
1085                 next_event = events.end();
1086                 return;
1087         }
1088
1089         if (next_event == events.end()) {
1090                 next_event = events.begin();
1091         }
1092
1093         if ((*next_event)->action_frame > _transport_frame) {
1094                 next_event = events.begin();
1095         }
1096
1097         for (; next_event != events.end(); ++next_event) {
1098                 if ((*next_event)->action_frame >= _transport_frame) {
1099                         break;
1100                 }
1101         }
1102 }
1103
1104 void
1105 Session::process_event (SessionEvent* ev)
1106 {
1107         bool remove = true;
1108         bool del = true;
1109
1110         /* if we're in the middle of a state change (i.e. waiting
1111            for the butler thread to complete the non-realtime
1112            part of the change), we'll just have to queue this
1113            event for a time when the change is complete.
1114         */
1115
1116         if (non_realtime_work_pending()) {
1117
1118                 /* except locates, which we have the capability to handle */
1119
1120                 if (ev->type != SessionEvent::Locate) {
1121                         immediate_events.insert (immediate_events.end(), ev);
1122                         _remove_event (ev);
1123                         return;
1124                 }
1125         }
1126
1127         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1128
1129         switch (ev->type) {
1130         case SessionEvent::SetLoop:
1131                 set_play_loop (ev->yes_or_no, ev->speed);
1132                 break;
1133
1134         case SessionEvent::AutoLoop:
1135                 if (play_loop) {
1136                         /* roll after locate, do not flush, set "with loop"
1137                            true only if we are seamless looping
1138                         */
1139                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1140                 }
1141                 remove = false;
1142                 del = false;
1143                 break;
1144
1145         case SessionEvent::AutoLoopDeclick:
1146                 if (play_loop) {
1147                         /* Request a declick fade-out and a fade-in; the fade-out will happen
1148                            at the end of the loop, and the fade-in at the start.
1149                         */
1150                         transport_sub_state |= (PendingLoopDeclickOut | PendingLoopDeclickIn);
1151                 }
1152                 remove = false;
1153                 del = false;
1154                 break;
1155
1156         case SessionEvent::Locate:
1157                 if (ev->yes_or_no) {
1158                         /* args: do not roll after locate, do flush, not with loop */
1159                         locate (ev->target_frame, false, true, false);
1160                 } else {
1161                         /* args: do not roll after locate, do flush, not with loop */
1162                         start_locate (ev->target_frame, false, true, false);
1163                 }
1164                 _send_timecode_update = true;
1165                 break;
1166
1167         case SessionEvent::LocateRoll:
1168                 if (ev->yes_or_no) {
1169                         /* args: roll after locate, do flush, not with loop */
1170                         locate (ev->target_frame, true, true, false);
1171                 } else {
1172                         /* args: roll after locate, do flush, not with loop */
1173                         start_locate (ev->target_frame, true, true, false);
1174                 }
1175                 _send_timecode_update = true;
1176                 break;
1177
1178         case SessionEvent::Skip:
1179                 if (Config->get_skip_playback()) {
1180                         start_locate (ev->target_frame, true, true, false);
1181                         _send_timecode_update = true;
1182                 }
1183                 remove = false;
1184                 del = false;
1185                 break;
1186
1187         case SessionEvent::LocateRollLocate:
1188                 // locate is handled by ::request_roll_at_and_return()
1189                 _requested_return_frame = ev->target_frame;
1190                 request_locate (ev->target2_frame, true);
1191                 break;
1192
1193
1194         case SessionEvent::SetTransportSpeed:
1195                 set_transport_speed (ev->speed, ev->target_frame, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1196                 break;
1197
1198         case SessionEvent::PunchIn:
1199                 // cerr << "PunchIN at " << transport_frame() << endl;
1200                 if (config.get_punch_in() && record_status() == Enabled && !preroll_record_punch_enabled()) {
1201                         enable_record ();
1202                 }
1203                 remove = false;
1204                 del = false;
1205                 break;
1206
1207         case SessionEvent::PunchOut:
1208                 // cerr << "PunchOUT at " << transport_frame() << endl;
1209                 if (config.get_punch_out() && !preroll_record_punch_enabled()) {
1210                         step_back_from_record ();
1211                 }
1212                 remove = false;
1213                 del = false;
1214                 break;
1215
1216         case SessionEvent::RecordStart:
1217                 if (preroll_record_punch_enabled() && record_status() == Enabled) {
1218                         enable_record ();
1219                 }
1220                 remove = false;
1221                 del = false;
1222                 break;
1223
1224         case SessionEvent::StopOnce:
1225                 if (!non_realtime_work_pending()) {
1226                         _clear_event_type (SessionEvent::StopOnce);
1227                         stop_transport (ev->yes_or_no);
1228                 }
1229                 remove = false;
1230                 del = false;
1231                 break;
1232
1233         case SessionEvent::RangeStop:
1234                 if (!non_realtime_work_pending()) {
1235                         stop_transport (ev->yes_or_no);
1236                 }
1237                 remove = false;
1238                 del = false;
1239                 break;
1240
1241         case SessionEvent::RangeLocate:
1242                 /* args: roll after locate, do flush, not with loop */
1243                 start_locate (ev->target_frame, true, true, false);
1244                 remove = false;
1245                 del = false;
1246                 break;
1247
1248         case SessionEvent::Overwrite:
1249                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1250                 break;
1251
1252         case SessionEvent::SetSyncSource:
1253                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1254                 use_sync_source (ev->slave);
1255                 break;
1256
1257         case SessionEvent::Audition:
1258                 set_audition (ev->region);
1259                 // drop reference to region
1260                 ev->region.reset ();
1261                 break;
1262
1263         case SessionEvent::SetPlayAudioRange:
1264                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1265                 break;
1266
1267         case SessionEvent::CancelPlayAudioRange:
1268                 unset_play_range();
1269                 break;
1270
1271         case SessionEvent::RealTimeOperation:
1272                 process_rtop (ev);
1273                 del = false; // other side of RT request needs to clean up
1274                 break;
1275
1276         case SessionEvent::AdjustPlaybackBuffering:
1277                 schedule_playback_buffering_adjustment ();
1278                 break;
1279
1280         case SessionEvent::AdjustCaptureBuffering:
1281                 schedule_capture_buffering_adjustment ();
1282                 break;
1283
1284         case SessionEvent::SetTimecodeTransmission:
1285                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1286                 break;
1287
1288         default:
1289           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1290                 abort(); /*NOTREACHED*/
1291                 break;
1292         };
1293
1294         if (remove) {
1295                 del = del && !_remove_event (ev);
1296         }
1297
1298         if (del) {
1299                 delete ev;
1300         }
1301 }
1302
1303 framepos_t
1304 Session::compute_stop_limit () const
1305 {
1306         if (!Config->get_stop_at_session_end ()) {
1307                 return max_framepos;
1308         }
1309
1310         if (_slave) {
1311                 return max_framepos;
1312         }
1313
1314         if (preroll_record_punch_enabled ()) {
1315                 return max_framepos;
1316         }
1317
1318         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1319         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1320
1321         if (actively_recording ()) {
1322                 /* permanently recording */
1323                 return max_framepos;
1324         } else if (punching_in && !punching_out) {
1325                 /* punching in but never out */
1326                 return max_framepos;
1327         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_frame()) {
1328                 /* punching in and punching out after session end */
1329                 return max_framepos;
1330         }
1331
1332         return current_end_frame ();
1333 }
1334
1335
1336
1337 /* dedicated thread for signal emission.
1338  *
1339  * while sending cross-thread signals from the process thread
1340  * is fine in general, PBD::Signal's use of boost::function and
1341  * boost:bind can produce a vast overhead which is not
1342  * acceptable for low latency.
1343  *
1344  * This works around the issue by moving the boost overhead
1345  * out of the RT thread. The overall load is probably higher but
1346  * the realtime thread remains unaffected.
1347  */
1348
1349 void
1350 Session::emit_route_signals ()
1351 {
1352         // TODO use RAII to allow using these signals in other places
1353         BatchUpdateStart(); /* EMIT SIGNAL */
1354         boost::shared_ptr<RouteList> r = routes.reader ();
1355         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1356                 (*ci)->emit_pending_signals ();
1357         }
1358         BatchUpdateEnd(); /* EMIT SIGNAL */
1359 }
1360
1361 void
1362 Session::emit_thread_start ()
1363 {
1364         if (_rt_thread_active) {
1365                 return;
1366         }
1367         _rt_thread_active = true;
1368
1369         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1370                 _rt_thread_active = false;
1371         }
1372 }
1373
1374 void
1375 Session::emit_thread_terminate ()
1376 {
1377         if (!_rt_thread_active) {
1378                 return;
1379         }
1380         _rt_thread_active = false;
1381
1382         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1383                 pthread_cond_signal (&_rt_emit_cond);
1384                 pthread_mutex_unlock (&_rt_emit_mutex);
1385         }
1386
1387         void *status;
1388         pthread_join (_rt_emit_thread, &status);
1389 }
1390
1391 void *
1392 Session::emit_thread (void *arg)
1393 {
1394         Session *s = static_cast<Session *>(arg);
1395         s->emit_thread_run ();
1396         pthread_exit (0);
1397         return 0;
1398 }
1399
1400 void
1401 Session::emit_thread_run ()
1402 {
1403         pthread_mutex_lock (&_rt_emit_mutex);
1404         while (_rt_thread_active) {
1405                 emit_route_signals();
1406                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1407         }
1408         pthread_mutex_unlock (&_rt_emit_mutex);
1409 }