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/thread.h>
  29
  30 #include "ardour/ardour.h"
  31 #include "ardour/audioengine.h"
  32 #include "ardour/auditioner.h"
  33 #include "ardour/butler.h"
  34 #include "ardour/debug.h"
  35 #include "ardour/process_thread.h"
  36 #include "ardour/session.h"
  37 #include "ardour/slave.h"
  38 #include "ardour/timestamps.h"
  39 #include "ardour/graph.h"
  40 #include "ardour/audio_port.h"
  41
  42 #include "midi++/manager.h"
  43 #include "midi++/mmc.h"
  44
  45 #include "i18n.h"
  46
  47 using namespace ARDOUR;
  48 using namespace PBD;
  49 using namespace std;
  50
  51 /** Called by the audio engine when there is work to be done with JACK.
  52  * @param nframes Number of frames to process.
  53  */
  54 void
  55 Session::process (pframes_t nframes)
  56 {
  57         MIDI::Manager::instance()->cycle_start(nframes);
  58
  59         _silent = false;
  60
  61         if (processing_blocked()) {
  62                 _silent = true;
  63                 return;
  64         }
  65
  66         if (non_realtime_work_pending()) {
  67                 if (!_butler->transport_work_requested ()) {
  68                         post_transport ();
  69                 }
  70         }
  71
  72         _engine.main_thread()->get_buffers ();
  73
  74         (this->*process_function) (nframes);
  75
  76         _engine.main_thread()->drop_buffers ();
  77
  78         // the ticker is for sending time information like MidiClock
  79         framepos_t transport_frames = transport_frame();
  80         Timecode::BBT_Time transport_bbt;
  81         bbt_time(transport_frames, transport_bbt);
  82         Timecode::Time transport_timecode;
  83         timecode_time(transport_frames, transport_timecode);
  84         tick (transport_frames, transport_bbt, transport_timecode); /* EMIT SIGNAL */
  85
  86         SendFeedback (); /* EMIT SIGNAL */
  87
  88         MIDI::Manager::instance()->cycle_end();
  89 }
  90
  91 int
  92 Session::fail_roll (pframes_t nframes)
  93 {
  94         return no_roll (nframes);
  95 }
  96
  97 int
  98 Session::no_roll (pframes_t nframes)
  99 {
 100         framepos_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 101         int ret = 0;
 102         bool declick = get_transport_declick_required();
 103         boost::shared_ptr<RouteList> r = routes.reader ();
 104
 105         if (_click_io) {
 106                 _click_io->silence (nframes);
 107         }
 108
 109         DEBUG_TRACE(DEBUG::Graph,"calling graph/no-roll\n");
 110         route_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), actively_recording(), declick);
 111         /*
 112         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 113
 114                 if ((*i)->is_hidden()) {
 115                         continue;
 116                 }
 117
 118                 (*i)->set_pending_declick (declick);
 119
 120                 if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending(),
 121                                    actively_recording(), declick)) {
 122                         error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 123                         ret = -1;
 124                         break;
 125                 }
 126         }
 127         */
 128
 129         return ret;
 130 }
 131
 132 int
 133 Session::process_routes (pframes_t nframes, bool& need_butler)
 134 {
 135         bool record_active;
 136         int  declick = get_transport_declick_required();
 137         bool rec_monitors = get_rec_monitors_input();
 138         boost::shared_ptr<RouteList> r = routes.reader ();
 139
 140         if (transport_sub_state & StopPendingCapture) {
 141                 /* force a declick out */
 142                 declick = -1;
 143         }
 144
 145         record_active = actively_recording(); // || (get_record_enabled() && get_punch_in());
 146
 147         const framepos_t start_frame = _transport_frame;
 148         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 149
 150         DEBUG_TRACE(DEBUG::Graph,"calling graph/process-routes\n");
 151         route_graph->process_routes( nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler);
 152 /*
 153         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 154
 155                 int ret;
 156
 157                 if ((*i)->is_hidden()) {
 158                         continue;
 159                 }
 160
 161                 (*i)->set_pending_declick (declick);
 162
 163                 if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler)) < 0) {
 164                         stop_transport ();
 165                         return -1;
 166                 }
 167         }
 168 */
 169         return 0;
 170 }
 171
 172 int
 173 Session::silent_process_routes (pframes_t nframes, bool& need_butler)
 174 {
 175         bool record_active = actively_recording();
 176         int  declick = get_transport_declick_required();
 177         bool rec_monitors = get_rec_monitors_input();
 178         boost::shared_ptr<RouteList> r = routes.reader ();
 179
 180         if (transport_sub_state & StopPendingCapture) {
 181                 /* force a declick out */
 182                 declick = -1;
 183         }
 184
 185         const framepos_t start_frame = _transport_frame;
 186         const framepos_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 187
 188         route_graph->silent_process_routes( nframes, start_frame, end_frame, record_active, rec_monitors, need_butler);
 189 /*
 190         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 191
 192                 int ret;
 193
 194                 if ((*i)->is_hidden()) {
 195                         continue;
 196                 }
 197
 198                 if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, record_active, rec_monitors, need_butler)) < 0) {
 199                         stop_transport ();
 200                         return -1;
 201                 }
 202         }
 203 */
 204         return 0;
 205 }
 206
 207 void
 208 Session::get_track_statistics ()
 209 {
 210         float pworst = 1.0f;
 211         float cworst = 1.0f;
 212
 213         boost::shared_ptr<RouteList> rl = routes.reader();
 214         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 215
 216                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 217
 218                 if (!tr || tr->hidden()) {
 219                         continue;
 220                 }
 221
 222                 pworst = min (pworst, tr->playback_buffer_load());
 223                 cworst = min (cworst, tr->capture_buffer_load());
 224         }
 225
 226         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 227         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 228
 229         if (actively_recording()) {
 230                 set_dirty();
 231         }
 232 }
 233
 234 /** Process callback used when the auditioner is not active */
 235 void
 236 Session::process_with_events (pframes_t nframes)
 237 {
 238         SessionEvent*  ev;
 239         pframes_t      this_nframes;
 240         framepos_t     end_frame;
 241         bool           session_needs_butler = false;
 242         framepos_t     stop_limit;
 243         framecnt_t     frames_moved;
 244
 245         /* make sure the auditioner is silent */
 246
 247         if (auditioner) {
 248                 auditioner->silence (nframes);
 249         }
 250
 251         /* handle any pending events */
 252
 253         while (pending_events.read (&ev, 1) == 1) {
 254                 merge_event (ev);
 255         }
 256
 257         /* if we are not in the middle of a state change,
 258            and there are immediate events queued up,
 259            process them.
 260         */
 261
 262         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 263                 SessionEvent *ev = immediate_events.front ();
 264                 immediate_events.pop_front ();
 265                 process_event (ev);
 266         }
 267
 268         /* Events caused a transport change, send an MTC Full Frame (Timecode) message.
 269          * This is sent whether rolling or not, to give slaves an idea of ardour time
 270          * on locates (and allow slow slaves to position and prepare for rolling)
 271          */
 272         if (_send_timecode_update) {
 273                 send_full_time_code (_transport_frame);
 274         }
 275
 276         if (!process_can_proceed()) {
 277                 _silent = true;
 278                 return;
 279         }
 280
 281         if (events.empty() || next_event == events.end()) {
 282                 process_without_events (nframes);
 283                 return;
 284         }
 285
 286         if (_transport_speed == 1.0) {
 287                 frames_moved = (framecnt_t) nframes;
 288         } else {
 289                 interpolation.set_target_speed (fabs(_target_transport_speed));
 290                 interpolation.set_speed (fabs(_transport_speed));
 291                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 292         }
 293
 294         end_frame = _transport_frame + frames_moved;
 295
 296         {
 297                 SessionEvent* this_event;
 298                 Events::iterator the_next_one;
 299
 300                 if (!process_can_proceed()) {
 301                         _silent = true;
 302                         return;
 303                 }
 304
 305                 if (!_exporting && _slave) {
 306                         if (!follow_slave (nframes)) {
 307                                 return;
 308                         }
 309                 }
 310
 311                 if (_transport_speed == 0) {
 312                         no_roll (nframes);
 313                         return;
 314                 }
 315
 316                 if (!_exporting && !timecode_transmission_suspended()) {
 317                         send_midi_time_code_for_cycle (nframes);
 318                 }
 319
 320                 if (actively_recording()) {
 321                         stop_limit = max_framepos;
 322                 } else {
 323
 324                         if (Config->get_stop_at_session_end()) {
 325                                 stop_limit = current_end_frame();
 326                         } else {
 327                                 stop_limit = max_framepos;
 328                         }
 329                 }
 330
 331                 if (maybe_stop (stop_limit)) {
 332                         no_roll (nframes);
 333                         return;
 334                 }
 335
 336                 this_event = *next_event;
 337                 the_next_one = next_event;
 338                 ++the_next_one;
 339
 340                 /* yes folks, here it is, the actual loop where we really truly
 341                    process some audio
 342                 */
 343
 344                 while (nframes) {
 345
 346                         this_nframes = nframes; /* real (jack) time relative */
 347                         frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 348
 349                         /* running an event, position transport precisely to its time */
 350                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 351                                 /* this isn't quite right for reverse play */
 352                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 353                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 354                         }
 355
 356                         if (this_nframes) {
 357
 358                                 click (_transport_frame, this_nframes);
 359
 360                                 if (process_routes (this_nframes, session_needs_butler)) {
 361                                         fail_roll (nframes);
 362                                         return;
 363                                 }
 364
 365                                 get_track_statistics ();
 366
 367                                 nframes -= this_nframes;
 368
 369                                 if (frames_moved < 0) {
 370                                         decrement_transport_position (-frames_moved);
 371                                 } else {
 372                                         increment_transport_position (frames_moved);
 373                                 }
 374
 375                                 maybe_stop (stop_limit);
 376                                 check_declick_out ();
 377                         }
 378
 379                         _engine.split_cycle (this_nframes);
 380
 381                         /* now handle this event and all others scheduled for the same time */
 382
 383                         while (this_event && this_event->action_frame == _transport_frame) {
 384                                 process_event (this_event);
 385
 386                                 if (the_next_one == events.end()) {
 387                                         this_event = 0;
 388                                 } else {
 389                                         this_event = *the_next_one;
 390                                         ++the_next_one;
 391                                 }
 392                         }
 393
 394                         /* if an event left our state changing, do the right thing */
 395
 396                         if (nframes && non_realtime_work_pending()) {
 397                                 no_roll (nframes);
 398                                 break;
 399                         }
 400
 401                         /* this is necessary to handle the case of seamless looping */
 402                         end_frame = _transport_frame + floor (nframes * _transport_speed);
 403
 404                 }
 405
 406                 set_next_event ();
 407
 408         } /* implicit release of route lock */
 409
 410         if (session_needs_butler) {
 411                 _butler->summon ();
 412         }
 413 }
 414
 415 void
 416 Session::reset_slave_state ()
 417 {
 418         average_slave_delta = 1800;
 419         delta_accumulator_cnt = 0;
 420         have_first_delta_accumulator = false;
 421         _slave_state = Stopped;
 422 }
 423
 424 bool
 425 Session::transport_locked () const
 426 {
 427         Slave* sl = _slave;
 428
 429         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 430                 return true;
 431         }
 432
 433         return false;
 434 }
 435
 436 bool
 437 Session::follow_slave (pframes_t nframes)
 438 {
 439         double slave_speed;
 440         framepos_t slave_transport_frame;
 441         framecnt_t this_delta;
 442         int dir;
 443
 444         if (!_slave->ok()) {
 445                 stop_transport ();
 446                 config.set_external_sync (false);
 447                 goto noroll;
 448         }
 449
 450         _slave->speed_and_position (slave_speed, slave_transport_frame);
 451
 452         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 453
 454         if (!_slave->locked()) {
 455                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 456                 goto noroll;
 457         }
 458
 459         if (slave_transport_frame > _transport_frame) {
 460                 this_delta = slave_transport_frame - _transport_frame;
 461                 dir = 1;
 462         } else {
 463                 this_delta = _transport_frame - slave_transport_frame;
 464                 dir = -1;
 465         }
 466
 467         if (_slave->starting()) {
 468                 slave_speed = 0.0f;
 469         }
 470
 471         if (_slave->is_always_synced() || config.get_timecode_source_is_synced()) {
 472
 473                 /* if the TC source is synced, then we assume that its
 474                    speed is binary: 0.0 or 1.0
 475                 */
 476
 477                 if (slave_speed != 0.0f) {
 478                         slave_speed = 1.0f;
 479                 }
 480
 481         } else {
 482
 483                 /* if we are chasing and the average delta between us and the
 484                    master gets too big, we want to switch to silent
 485                    motion. so keep track of that here.
 486                 */
 487
 488                 if (_slave_state == Running) {
 489                         calculate_moving_average_of_slave_delta(dir, this_delta);
 490                 }
 491         }
 492
 493         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 494
 495         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 496                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 497
 498
 499         if (_slave_state == Running && !_slave->is_always_synced() && !config.get_timecode_source_is_synced()) {
 500
 501                 if (_transport_speed != 0.0f) {
 502
 503                         /*
 504                            note that average_dir is +1 or -1
 505                         */
 506
 507                         float delta;
 508
 509                         if (average_slave_delta == 0) {
 510                                 delta = this_delta;
 511                                 delta *= dir;
 512                         } else {
 513                                 delta = average_slave_delta;
 514                                 delta *= average_dir;
 515                         }
 516
 517 #ifndef NDEBUG
 518                         if (slave_speed != 0.0) {
 519                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 520                                                                            (int) (dir * this_delta),
 521                                                                            slave_speed,
 522                                                                            _transport_speed,
 523                                                                            _transport_frame,
 524                                                                            slave_transport_frame,
 525                                                                            average_slave_delta));
 526                         }
 527 #endif
 528
 529                         if (_slave->give_slave_full_control_over_transport_speed()) {
 530                                 set_transport_speed (slave_speed, false, false);
 531                                 //std::cout << "set speed = " << slave_speed << "\n";
 532                         } else {
 533                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 534                                 request_transport_speed (adjusted_speed);
 535                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 536                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 537                                                                            slave_speed));
 538                         }
 539
 540 #if 1
 541                         if ((framecnt_t) abs(average_slave_delta) > _slave->resolution()) {
 542                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 543                                 goto silent_motion;
 544                         }
 545 #endif
 546                 }
 547         }
 548
 549
 550         if (_slave_state == Running && !non_realtime_work_pending()) {
 551                 /* speed is set, we're locked, and good to go */
 552                 return true;
 553         }
 554
 555   silent_motion:
 556         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 557         follow_slave_silently (nframes, slave_speed);
 558
 559   noroll:
 560         /* don't move at all */
 561         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 562         no_roll (nframes);
 563         return false;
 564 }
 565
 566 void
 567 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 568 {
 569         if (delta_accumulator_cnt >= delta_accumulator_size) {
 570                 have_first_delta_accumulator = true;
 571                 delta_accumulator_cnt = 0;
 572         }
 573
 574         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 575                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 576         }
 577
 578         if (have_first_delta_accumulator) {
 579                 average_slave_delta = 0L;
 580                 for (int i = 0; i < delta_accumulator_size; ++i) {
 581                         average_slave_delta += delta_accumulator[i];
 582                 }
 583                 average_slave_delta /= (int32_t) delta_accumulator_size;
 584                 if (average_slave_delta < 0L) {
 585                         average_dir = -1;
 586                         average_slave_delta = abs(average_slave_delta);
 587                 } else {
 588                         average_dir = 1;
 589                 }
 590         }
 591 }
 592
 593 void
 594 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t this_delta)
 595 {
 596         if (slave_speed != 0.0f) {
 597
 598                 /* slave is running */
 599
 600                 switch (_slave_state) {
 601                 case Stopped:
 602                         if (_slave->requires_seekahead()) {
 603                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 604                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 605                                 /* we can call locate() here because we are in process context */
 606                                 locate (slave_wait_end, false, false);
 607                                 _slave_state = Waiting;
 608
 609                         } else {
 610
 611                                 _slave_state = Running;
 612
 613                                 Location* al = _locations->auto_loop_location();
 614
 615                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 616                                         // cancel looping
 617                                         request_play_loop(false);
 618                                 }
 619
 620                                 if (slave_transport_frame != _transport_frame) {
 621                                         locate (slave_transport_frame, false, false);
 622                                 }
 623                         }
 624                         break;
 625
 626                 case Waiting:
 627                 default:
 628                         break;
 629                 }
 630
 631                 if (_slave_state == Waiting) {
 632
 633                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 634
 635                         if (slave_transport_frame >= slave_wait_end) {
 636
 637                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 638
 639                                 _slave_state = Running;
 640
 641                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 642                                    precisely with the master.
 643                                 */
 644
 645
 646                                 bool ok = true;
 647                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 648
 649                                 boost::shared_ptr<RouteList> rl = routes.reader();
 650                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 651                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 652                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 653                                                 ok = false;
 654                                                 break;
 655                                         }
 656                                 }
 657
 658                                 if (ok) {
 659                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 660                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 661                                                 if (tr) {
 662                                                         tr->internal_playback_seek (frame_delta);
 663                                                 }
 664                                         }
 665                                         _transport_frame += frame_delta;
 666
 667                                 } else {
 668                                         cerr << "cannot micro-seek\n";
 669                                         /* XXX what? */
 670                                 }
 671
 672                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 673                                 average_slave_delta = 0L;
 674                                 this_delta = 0;
 675                         }
 676                 }
 677
 678                 if (_slave_state == Running && _transport_speed == 0.0f) {
 679                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 680                         start_transport ();
 681                 }
 682
 683         } else { // slave_speed is 0
 684
 685                 /* slave has stopped */
 686
 687                 if (_transport_speed != 0.0f) {
 688                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 689                         stop_transport();
 690                 }
 691
 692                 if (slave_transport_frame != _transport_frame) {
 693                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 694                         force_locate (slave_transport_frame, false);
 695                 }
 696
 697                 _slave_state = Stopped;
 698         }
 699 }
 700
 701 void
 702 Session::follow_slave_silently (pframes_t nframes, float slave_speed)
 703 {
 704         if (slave_speed && _transport_speed) {
 705
 706                 /* something isn't right, but we should move with the master
 707                    for now.
 708                 */
 709
 710                 bool need_butler;
 711
 712                 silent_process_routes (nframes, need_butler);
 713
 714                 get_track_statistics ();
 715
 716                 if (need_butler) {
 717                         _butler->summon ();
 718                 }
 719
 720                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 721
 722                 if (frames_moved < 0) {
 723                         decrement_transport_position (-frames_moved);
 724                 } else {
 725                         increment_transport_position (frames_moved);
 726                 }
 727
 728                 framepos_t stop_limit;
 729
 730                 if (actively_recording()) {
 731                         stop_limit = max_framepos;
 732                 } else {
 733                         if (Config->get_stop_at_session_end()) {
 734                                 stop_limit = current_end_frame();
 735                         } else {
 736                                 stop_limit = max_framepos;
 737                         }
 738                 }
 739
 740                 maybe_stop (stop_limit);
 741         }
 742 }
 743
 744 void
 745 Session::process_without_events (pframes_t nframes)
 746 {
 747         bool session_needs_butler = false;
 748         framepos_t stop_limit;
 749         framecnt_t frames_moved;
 750
 751         if (!process_can_proceed()) {
 752                 _silent = true;
 753                 return;
 754         }
 755
 756         if (!_exporting && _slave) {
 757                 if (!follow_slave (nframes)) {
 758                         return;
 759                 }
 760         }
 761
 762         if (_transport_speed == 0) {
 763                 fail_roll (nframes);
 764                 return;
 765         }
 766
 767         if (!_exporting && !timecode_transmission_suspended()) {
 768                 send_midi_time_code_for_cycle (nframes);
 769         }
 770
 771         if (actively_recording()) {
 772                 stop_limit = max_framepos;
 773         } else {
 774                 if (Config->get_stop_at_session_end()) {
 775                         stop_limit = current_end_frame();
 776                 } else {
 777                         stop_limit = max_framepos;
 778                 }
 779         }
 780
 781         if (maybe_stop (stop_limit)) {
 782                 fail_roll (nframes);
 783                 return;
 784         }
 785
 786         if (maybe_sync_start (nframes)) {
 787                 return;
 788         }
 789
 790         click (_transport_frame, nframes);
 791
 792         if (_transport_speed == 1.0) {
 793                 frames_moved = (framecnt_t) nframes;
 794         } else {
 795                 interpolation.set_target_speed (fabs(_target_transport_speed));
 796                 interpolation.set_speed (fabs(_transport_speed));
 797                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 798         }
 799
 800         if (process_routes (nframes, session_needs_butler)) {
 801                 fail_roll (nframes);
 802                 return;
 803         }
 804
 805         get_track_statistics ();
 806
 807         if (frames_moved < 0) {
 808                 decrement_transport_position (-frames_moved);
 809         } else {
 810                 increment_transport_position (frames_moved);
 811         }
 812
 813         maybe_stop (stop_limit);
 814         check_declick_out ();
 815
 816         if (session_needs_butler) {
 817                 _butler->summon ();
 818         }
 819 }
 820
 821 /** Process callback used when the auditioner is active.
 822  * @param nframes number of frames to process.
 823  */
 824 void
 825 Session::process_audition (pframes_t nframes)
 826 {
 827         SessionEvent* ev;
 828         boost::shared_ptr<RouteList> r = routes.reader ();
 829
 830         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 831                 if (!(*i)->is_hidden()) {
 832                         (*i)->silence (nframes);
 833                 }
 834         }
 835
 836         /* run the auditioner, and if it says we need butler service, ask for it */
 837
 838         if (auditioner->play_audition (nframes) > 0) {
 839                 _butler->summon ();
 840         }
 841
 842         /* if using a monitor section, run it because otherwise we don't hear anything */
 843
 844         if (auditioner->needs_monitor()) {
 845                 _monitor_out->passthru (_transport_frame, _transport_frame + nframes, nframes, false);
 846         }
 847
 848         /* handle pending events */
 849
 850         while (pending_events.read (&ev, 1) == 1) {
 851                 merge_event (ev);
 852         }
 853
 854         /* if we are not in the middle of a state change,
 855            and there are immediate events queued up,
 856            process them.
 857         */
 858
 859         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 860                 SessionEvent *ev = immediate_events.front ();
 861                 immediate_events.pop_front ();
 862                 process_event (ev);
 863         }
 864
 865         if (!auditioner->auditioning()) {
 866                 /* auditioner no longer active, so go back to the normal process callback */
 867                 process_function = &Session::process_with_events;
 868         }
 869 }
 870
 871 bool
 872 Session::maybe_sync_start (pframes_t & nframes)
 873 {
 874         pframes_t sync_offset;
 875
 876         if (!waiting_for_sync_offset) {
 877                 return false;
 878         }
 879
 880         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 881
 882                 /* generate silence up to the sync point, then
 883                    adjust nframes + offset to reflect whatever
 884                    is left to do.
 885                 */
 886
 887                 no_roll (sync_offset);
 888                 nframes -= sync_offset;
 889                 AudioPort::increment_port_offset (sync_offset);
 890                 waiting_for_sync_offset = false;
 891
 892                 if (nframes == 0) {
 893                         return true; // done, nothing left to process
 894                 }
 895
 896         } else {
 897
 898                 /* sync offset point is not within this process()
 899                    cycle, so just generate silence. and don't bother
 900                    with any fancy stuff here, just the minimal silence.
 901                 */
 902
 903                 _silent = true;
 904
 905                 if (Config->get_locate_while_waiting_for_sync()) {
 906                         if (micro_locate (nframes)) {
 907                                 /* XXX ERROR !!! XXX */
 908                         }
 909                 }
 910
 911                 return true; // done, nothing left to process
 912         }
 913
 914         return false;
 915 }
 916
 917 void
 918 Session::queue_event (SessionEvent* ev)
 919 {
 920         if (_state_of_the_state & Deletion) {
 921                 return;
 922         } else if (_state_of_the_state & Loading) {
 923                 merge_event (ev);
 924         } else {
 925                 pending_events.write (&ev, 1);
 926         }
 927 }
 928
 929 void
 930 Session::set_next_event ()
 931 {
 932         if (events.empty()) {
 933                 next_event = events.end();
 934                 return;
 935         }
 936
 937         if (next_event == events.end()) {
 938                 next_event = events.begin();
 939         }
 940
 941         if ((*next_event)->action_frame > _transport_frame) {
 942                 next_event = events.begin();
 943         }
 944
 945         for (; next_event != events.end(); ++next_event) {
 946                 if ((*next_event)->action_frame >= _transport_frame) {
 947                         break;
 948                 }
 949         }
 950 }
 951
 952 void
 953 Session::process_event (SessionEvent* ev)
 954 {
 955         bool remove = true;
 956         bool del = true;
 957
 958         /* if we're in the middle of a state change (i.e. waiting
 959            for the butler thread to complete the non-realtime
 960            part of the change), we'll just have to queue this
 961            event for a time when the change is complete.
 962         */
 963
 964         if (non_realtime_work_pending()) {
 965
 966                 /* except locates, which we have the capability to handle */
 967
 968                 if (ev->type != SessionEvent::Locate) {
 969                         immediate_events.insert (immediate_events.end(), ev);
 970                         _remove_event (ev);
 971                         return;
 972                 }
 973         }
 974
 975         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
 976
 977         switch (ev->type) {
 978         case SessionEvent::SetLoop:
 979                 set_play_loop (ev->yes_or_no);
 980                 break;
 981
 982         case SessionEvent::AutoLoop:
 983                 if (play_loop) {
 984                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
 985                 }
 986                 remove = false;
 987                 del = false;
 988                 break;
 989
 990         case SessionEvent::Locate:
 991                 if (ev->yes_or_no) {
 992                         // cerr << "forced locate to " << ev->target_frame << endl;
 993                         locate (ev->target_frame, false, true, false);
 994                 } else {
 995                         // cerr << "soft locate to " << ev->target_frame << endl;
 996                         start_locate (ev->target_frame, false, true, false);
 997                 }
 998                 _send_timecode_update = true;
 999                 break;
1000
1001         case SessionEvent::LocateRoll:
1002                 if (ev->yes_or_no) {
1003                         // cerr << "forced locate to+roll " << ev->target_frame << endl;
1004                         locate (ev->target_frame, true, true, false);
1005                 } else {
1006                         // cerr << "soft locate to+roll " << ev->target_frame << endl;
1007                         start_locate (ev->target_frame, true, true, false);
1008                 }
1009                 _send_timecode_update = true;
1010                 break;
1011
1012         case SessionEvent::LocateRollLocate:
1013                 // locate is handled by ::request_roll_at_and_return()
1014                 _requested_return_frame = ev->target_frame;
1015                 request_locate (ev->target2_frame, true);
1016                 break;
1017
1018
1019         case SessionEvent::SetTransportSpeed:
1020                 set_transport_speed (ev->speed, ev->yes_or_no, ev->second_yes_or_no);
1021                 break;
1022
1023         case SessionEvent::PunchIn:
1024                 // cerr << "PunchIN at " << transport_frame() << endl;
1025                 if (config.get_punch_in() && record_status() == Enabled) {
1026                         enable_record ();
1027                 }
1028                 remove = false;
1029                 del = false;
1030                 break;
1031
1032         case SessionEvent::PunchOut:
1033                 // cerr << "PunchOUT at " << transport_frame() << endl;
1034                 if (config.get_punch_out()) {
1035                         step_back_from_record ();
1036                 }
1037                 remove = false;
1038                 del = false;
1039                 break;
1040
1041         case SessionEvent::StopOnce:
1042                 if (!non_realtime_work_pending()) {
1043                         stop_transport (ev->yes_or_no);
1044                         _clear_event_type (SessionEvent::StopOnce);
1045                 }
1046                 remove = false;
1047                 del = false;
1048                 break;
1049
1050         case SessionEvent::RangeStop:
1051                 if (!non_realtime_work_pending()) {
1052                         stop_transport (ev->yes_or_no);
1053                 }
1054                 remove = false;
1055                 del = false;
1056                 break;
1057
1058         case SessionEvent::RangeLocate:
1059                 start_locate (ev->target_frame, true, true, false);
1060                 remove = false;
1061                 del = false;
1062                 break;
1063
1064         case SessionEvent::Overwrite:
1065                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1066                 break;
1067
1068         case SessionEvent::SetTrackSpeed:
1069                 set_track_speed (static_cast<Track*> (ev->ptr), ev->speed);
1070                 break;
1071
1072         case SessionEvent::SetSyncSource:
1073                 use_sync_source (ev->slave);
1074                 break;
1075
1076         case SessionEvent::Audition:
1077                 set_audition (ev->region);
1078                 // drop reference to region
1079                 ev->region.reset ();
1080                 break;
1081
1082         case SessionEvent::InputConfigurationChange:
1083                 add_post_transport_work (PostTransportInputChange);
1084                 _butler->schedule_transport_work ();
1085                 break;
1086
1087         case SessionEvent::SetPlayAudioRange:
1088                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1089                 break;
1090
1091         case SessionEvent::RealTimeOperation:
1092                 process_rtop (ev);
1093                 del = false; // other side of RT request needs to clean up
1094                 break;
1095
1096         case SessionEvent::AdjustPlaybackBuffering:
1097                 schedule_playback_buffering_adjustment ();
1098                 break;
1099
1100         case SessionEvent::AdjustCaptureBuffering:
1101                 schedule_capture_buffering_adjustment ();
1102                 break;
1103
1104         case SessionEvent::SetTimecodeTransmission:
1105                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1106                 break;
1107
1108         default:
1109           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1110                 /*NOTREACHED*/
1111                 break;
1112         };
1113
1114         if (remove) {
1115                 del = del && !_remove_event (ev);
1116         }
1117
1118         if (del) {
1119                 delete ev;
1120         }
1121 }
1122