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         if (Config->get_processor_usage() != 1) {
 110                 DEBUG_TRACE(DEBUG::Graph,"calling graph/no-roll\n");
 111                 route_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), actively_recording(), declick);
 112         } else {
 113                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 114
 115                         if ((*i)->is_hidden()) {
 116                                 continue;
 117                         }
 118
 119                         (*i)->set_pending_declick (declick);
 120
 121                         if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending(),
 122                                            actively_recording(), declick)) {
 123                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 124                                 ret = -1;
 125                                 break;
 126                         }
 127                 }
 128         }
 129
 130         return ret;
 131 }
 132
 133 int
 134 Session::process_routes (pframes_t nframes, bool& need_butler)
 135 {
 136         bool record_active;
 137         int  declick = get_transport_declick_required();
 138         bool rec_monitors = get_rec_monitors_input();
 139         boost::shared_ptr<RouteList> r = routes.reader ();
 140
 141         if (transport_sub_state & StopPendingCapture) {
 142                 /* force a declick out */
 143                 declick = -1;
 144         }
 145
 146         record_active = actively_recording(); // || (get_record_enabled() && get_punch_in());
 147
 148         const framepos_t start_frame = _transport_frame;
 149         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 150
 151         if (Config->get_processor_usage() != 1) {
 152                 DEBUG_TRACE(DEBUG::Graph,"calling graph/process-routes\n");
 153                 route_graph->process_routes( nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler);
 154
 155         } else {
 156
 157                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 158
 159                         int ret;
 160
 161                         if ((*i)->is_hidden()) {
 162                                 continue;
 163                         }
 164
 165                         (*i)->set_pending_declick (declick);
 166
 167                         if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, record_active, rec_monitors, need_butler)) < 0) {
 168                                 stop_transport ();
 169                                 return -1;
 170                         }
 171                 }
 172         }
 173
 174         return 0;
 175 }
 176
 177 int
 178 Session::silent_process_routes (pframes_t nframes, bool& need_butler)
 179 {
 180         bool record_active = actively_recording();
 181         int  declick = get_transport_declick_required();
 182         bool rec_monitors = get_rec_monitors_input();
 183         boost::shared_ptr<RouteList> r = routes.reader ();
 184
 185         if (transport_sub_state & StopPendingCapture) {
 186                 /* force a declick out */
 187                 declick = -1;
 188         }
 189
 190         const framepos_t start_frame = _transport_frame;
 191         const framepos_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 192
 193         if (Config->get_processor_usage() != 1) {
 194                 cerr << "GRAPH PROCESS\n";
 195                 route_graph->silent_process_routes( nframes, start_frame, end_frame, record_active, rec_monitors, need_butler);
 196         } else {
 197                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 198
 199                         int ret;
 200
 201                         if ((*i)->is_hidden()) {
 202                                 continue;
 203                         }
 204
 205                         if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, record_active, rec_monitors, need_butler)) < 0) {
 206                                 stop_transport ();
 207                                 return -1;
 208                         }
 209                 }
 210         }
 211
 212         return 0;
 213 }
 214
 215 void
 216 Session::get_track_statistics ()
 217 {
 218         float pworst = 1.0f;
 219         float cworst = 1.0f;
 220
 221         boost::shared_ptr<RouteList> rl = routes.reader();
 222         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 223
 224                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 225
 226                 if (!tr || tr->hidden()) {
 227                         continue;
 228                 }
 229
 230                 pworst = min (pworst, tr->playback_buffer_load());
 231                 cworst = min (cworst, tr->capture_buffer_load());
 232         }
 233
 234         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 235         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 236
 237         if (actively_recording()) {
 238                 set_dirty();
 239         }
 240 }
 241
 242 /** Process callback used when the auditioner is not active */
 243 void
 244 Session::process_with_events (pframes_t nframes)
 245 {
 246         SessionEvent*  ev;
 247         pframes_t      this_nframes;
 248         framepos_t     end_frame;
 249         bool           session_needs_butler = false;
 250         framepos_t     stop_limit;
 251         framecnt_t     frames_moved;
 252
 253         /* make sure the auditioner is silent */
 254
 255         if (auditioner) {
 256                 auditioner->silence (nframes);
 257         }
 258
 259         /* handle any pending events */
 260
 261         while (pending_events.read (&ev, 1) == 1) {
 262                 merge_event (ev);
 263         }
 264
 265         /* if we are not in the middle of a state change,
 266            and there are immediate events queued up,
 267            process them.
 268         */
 269
 270         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 271                 SessionEvent *ev = immediate_events.front ();
 272                 immediate_events.pop_front ();
 273                 process_event (ev);
 274         }
 275
 276         /* Decide on what to do with quarter-frame MTC during this cycle */
 277
 278         bool const was_sending_qf_mtc = _send_qf_mtc;
 279         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 280
 281         if (_transport_speed != 0) {
 282                 _send_qf_mtc = (
 283                         Config->get_send_mtc () &&
 284                         _transport_speed >= (1 - tolerance) &&
 285                         _transport_speed <= (1 + tolerance)
 286                         );
 287
 288                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 289                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 290                         _send_timecode_update = true;
 291                 }
 292
 293                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (frame_rate () / 4)) {
 294                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 295                            a quarter of a second since we sent anything at all, so send a full MTC update
 296                            this cycle.
 297                         */
 298                         _send_timecode_update = true;
 299                 }
 300
 301                 _pframes_since_last_mtc += nframes;
 302         }
 303
 304         /* Events caused a transport change (or we re-started sending
 305          * MTC), so send an MTC Full Frame (Timecode) message.  This
 306          * is sent whether rolling or not, to give slaves an idea of
 307          * ardour time on locates (and allow slow slaves to position
 308          * and prepare for rolling)
 309          */
 310         if (_send_timecode_update) {
 311                 send_full_time_code (_transport_frame);
 312         }
 313
 314         if (!process_can_proceed()) {
 315                 _silent = true;
 316                 return;
 317         }
 318
 319         if (events.empty() || next_event == events.end()) {
 320                 process_without_events (nframes);
 321                 return;
 322         }
 323
 324         if (_transport_speed == 1.0) {
 325                 frames_moved = (framecnt_t) nframes;
 326         } else {
 327                 interpolation.set_target_speed (fabs(_target_transport_speed));
 328                 interpolation.set_speed (fabs(_transport_speed));
 329                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 330         }
 331
 332         end_frame = _transport_frame + frames_moved;
 333
 334         {
 335                 SessionEvent* this_event;
 336                 Events::iterator the_next_one;
 337
 338                 if (!process_can_proceed()) {
 339                         _silent = true;
 340                         return;
 341                 }
 342
 343                 if (!_exporting && _slave) {
 344                         if (!follow_slave (nframes)) {
 345                                 return;
 346                         }
 347                 }
 348
 349                 if (_transport_speed == 0) {
 350                         no_roll (nframes);
 351                         return;
 352                 }
 353
 354                 if (!_exporting && !timecode_transmission_suspended()) {
 355                         send_midi_time_code_for_cycle (_transport_frame, end_frame, nframes);
 356                 }
 357
 358                 if (actively_recording()) {
 359                         stop_limit = max_framepos;
 360                 } else {
 361
 362                         if (Config->get_stop_at_session_end()) {
 363                                 stop_limit = current_end_frame();
 364                         } else {
 365                                 stop_limit = max_framepos;
 366                         }
 367                 }
 368
 369                 if (maybe_stop (stop_limit)) {
 370                         no_roll (nframes);
 371                         return;
 372                 }
 373
 374                 this_event = *next_event;
 375                 the_next_one = next_event;
 376                 ++the_next_one;
 377
 378                 /* yes folks, here it is, the actual loop where we really truly
 379                    process some audio
 380                 */
 381
 382                 while (nframes) {
 383
 384                         this_nframes = nframes; /* real (jack) time relative */
 385                         frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 386
 387                         /* running an event, position transport precisely to its time */
 388                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 389                                 /* this isn't quite right for reverse play */
 390                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 391                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 392                         }
 393
 394                         if (this_nframes) {
 395
 396                                 click (_transport_frame, this_nframes);
 397
 398                                 if (process_routes (this_nframes, session_needs_butler)) {
 399                                         fail_roll (nframes);
 400                                         return;
 401                                 }
 402
 403                                 get_track_statistics ();
 404
 405                                 nframes -= this_nframes;
 406
 407                                 if (frames_moved < 0) {
 408                                         decrement_transport_position (-frames_moved);
 409                                 } else {
 410                                         increment_transport_position (frames_moved);
 411                                 }
 412
 413                                 maybe_stop (stop_limit);
 414                                 check_declick_out ();
 415                         }
 416
 417                         _engine.split_cycle (this_nframes);
 418
 419                         /* now handle this event and all others scheduled for the same time */
 420
 421                         while (this_event && this_event->action_frame == _transport_frame) {
 422                                 process_event (this_event);
 423
 424                                 if (the_next_one == events.end()) {
 425                                         this_event = 0;
 426                                 } else {
 427                                         this_event = *the_next_one;
 428                                         ++the_next_one;
 429                                 }
 430                         }
 431
 432                         /* if an event left our state changing, do the right thing */
 433
 434                         if (nframes && non_realtime_work_pending()) {
 435                                 no_roll (nframes);
 436                                 break;
 437                         }
 438
 439                         /* this is necessary to handle the case of seamless looping */
 440                         end_frame = _transport_frame + floor (nframes * _transport_speed);
 441
 442                 }
 443
 444                 set_next_event ();
 445
 446         } /* implicit release of route lock */
 447
 448         if (session_needs_butler) {
 449                 _butler->summon ();
 450         }
 451 }
 452
 453 void
 454 Session::reset_slave_state ()
 455 {
 456         average_slave_delta = 1800;
 457         delta_accumulator_cnt = 0;
 458         have_first_delta_accumulator = false;
 459         _slave_state = Stopped;
 460 }
 461
 462 bool
 463 Session::transport_locked () const
 464 {
 465         Slave* sl = _slave;
 466
 467         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 468                 return true;
 469         }
 470
 471         return false;
 472 }
 473
 474 bool
 475 Session::follow_slave (pframes_t nframes)
 476 {
 477         double slave_speed;
 478         framepos_t slave_transport_frame;
 479         framecnt_t this_delta;
 480         int dir;
 481
 482         if (!_slave->ok()) {
 483                 stop_transport ();
 484                 config.set_external_sync (false);
 485                 goto noroll;
 486         }
 487
 488         _slave->speed_and_position (slave_speed, slave_transport_frame);
 489
 490         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 491
 492         if (!_slave->locked()) {
 493                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 494                 goto noroll;
 495         }
 496
 497         if (slave_transport_frame > _transport_frame) {
 498                 this_delta = slave_transport_frame - _transport_frame;
 499                 dir = 1;
 500         } else {
 501                 this_delta = _transport_frame - slave_transport_frame;
 502                 dir = -1;
 503         }
 504
 505         if (_slave->starting()) {
 506                 slave_speed = 0.0f;
 507         }
 508
 509         if (_slave->is_always_synced() || config.get_timecode_source_is_synced()) {
 510
 511                 /* if the TC source is synced, then we assume that its
 512                    speed is binary: 0.0 or 1.0
 513                 */
 514
 515                 if (slave_speed != 0.0f) {
 516                         slave_speed = 1.0f;
 517                 }
 518
 519         } else {
 520
 521                 /* if we are chasing and the average delta between us and the
 522                    master gets too big, we want to switch to silent
 523                    motion. so keep track of that here.
 524                 */
 525
 526                 if (_slave_state == Running) {
 527                         calculate_moving_average_of_slave_delta(dir, this_delta);
 528                 }
 529         }
 530
 531         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 532
 533         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 534                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 535
 536
 537         if (_slave_state == Running && !_slave->is_always_synced() && !config.get_timecode_source_is_synced()) {
 538
 539                 if (_transport_speed != 0.0f) {
 540
 541                         /*
 542                            note that average_dir is +1 or -1
 543                         */
 544
 545                         float delta;
 546
 547                         if (average_slave_delta == 0) {
 548                                 delta = this_delta;
 549                                 delta *= dir;
 550                         } else {
 551                                 delta = average_slave_delta;
 552                                 delta *= average_dir;
 553                         }
 554
 555 #ifndef NDEBUG
 556                         if (slave_speed != 0.0) {
 557                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 558                                                                            (int) (dir * this_delta),
 559                                                                            slave_speed,
 560                                                                            _transport_speed,
 561                                                                            _transport_frame,
 562                                                                            slave_transport_frame,
 563                                                                            average_slave_delta));
 564                         }
 565 #endif
 566
 567                         if (_slave->give_slave_full_control_over_transport_speed()) {
 568                                 set_transport_speed (slave_speed, false, false);
 569                                 //std::cout << "set speed = " << slave_speed << "\n";
 570                         } else {
 571                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 572                                 request_transport_speed (adjusted_speed);
 573                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 574                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 575                                                                            slave_speed));
 576                         }
 577
 578 #if 1
 579                         if ((framecnt_t) abs(average_slave_delta) > _slave->resolution()) {
 580                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 581                                 goto silent_motion;
 582                         }
 583 #endif
 584                 }
 585         }
 586
 587
 588         if (_slave_state == Running && !non_realtime_work_pending()) {
 589                 /* speed is set, we're locked, and good to go */
 590                 return true;
 591         }
 592
 593   silent_motion:
 594         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 595         follow_slave_silently (nframes, slave_speed);
 596
 597   noroll:
 598         /* don't move at all */
 599         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 600         no_roll (nframes);
 601         return false;
 602 }
 603
 604 void
 605 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 606 {
 607         if (delta_accumulator_cnt >= delta_accumulator_size) {
 608                 have_first_delta_accumulator = true;
 609                 delta_accumulator_cnt = 0;
 610         }
 611
 612         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 613                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 614         }
 615
 616         if (have_first_delta_accumulator) {
 617                 average_slave_delta = 0L;
 618                 for (int i = 0; i < delta_accumulator_size; ++i) {
 619                         average_slave_delta += delta_accumulator[i];
 620                 }
 621                 average_slave_delta /= (int32_t) delta_accumulator_size;
 622                 if (average_slave_delta < 0L) {
 623                         average_dir = -1;
 624                         average_slave_delta = abs(average_slave_delta);
 625                 } else {
 626                         average_dir = 1;
 627                 }
 628         }
 629 }
 630
 631 void
 632 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t this_delta)
 633 {
 634         if (slave_speed != 0.0f) {
 635
 636                 /* slave is running */
 637
 638                 switch (_slave_state) {
 639                 case Stopped:
 640                         if (_slave->requires_seekahead()) {
 641                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 642                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 643                                 /* we can call locate() here because we are in process context */
 644                                 locate (slave_wait_end, false, false);
 645                                 _slave_state = Waiting;
 646
 647                         } else {
 648
 649                                 _slave_state = Running;
 650
 651                                 Location* al = _locations->auto_loop_location();
 652
 653                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 654                                         // cancel looping
 655                                         request_play_loop(false);
 656                                 }
 657
 658                                 if (slave_transport_frame != _transport_frame) {
 659                                         locate (slave_transport_frame, false, false);
 660                                 }
 661                         }
 662                         break;
 663
 664                 case Waiting:
 665                 default:
 666                         break;
 667                 }
 668
 669                 if (_slave_state == Waiting) {
 670
 671                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 672
 673                         if (slave_transport_frame >= slave_wait_end) {
 674
 675                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 676
 677                                 _slave_state = Running;
 678
 679                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 680                                    precisely with the master.
 681                                 */
 682
 683
 684                                 bool ok = true;
 685                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 686
 687                                 boost::shared_ptr<RouteList> rl = routes.reader();
 688                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 689                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 690                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 691                                                 ok = false;
 692                                                 break;
 693                                         }
 694                                 }
 695
 696                                 if (ok) {
 697                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 698                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 699                                                 if (tr) {
 700                                                         tr->internal_playback_seek (frame_delta);
 701                                                 }
 702                                         }
 703                                         _transport_frame += frame_delta;
 704
 705                                 } else {
 706                                         cerr << "cannot micro-seek\n";
 707                                         /* XXX what? */
 708                                 }
 709
 710                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 711                                 average_slave_delta = 0L;
 712                                 this_delta = 0;
 713                         }
 714                 }
 715
 716                 if (_slave_state == Running && _transport_speed == 0.0f) {
 717                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 718                         start_transport ();
 719                 }
 720
 721         } else { // slave_speed is 0
 722
 723                 /* slave has stopped */
 724
 725                 if (_transport_speed != 0.0f) {
 726                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 727                         stop_transport ();
 728                 }
 729
 730                 if (slave_transport_frame != _transport_frame) {
 731                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 732                         force_locate (slave_transport_frame, false);
 733                 }
 734
 735                 _slave_state = Stopped;
 736         }
 737 }
 738
 739 void
 740 Session::follow_slave_silently (pframes_t nframes, float slave_speed)
 741 {
 742         if (slave_speed && _transport_speed) {
 743
 744                 /* something isn't right, but we should move with the master
 745                    for now.
 746                 */
 747
 748                 bool need_butler;
 749
 750                 silent_process_routes (nframes, need_butler);
 751
 752                 get_track_statistics ();
 753
 754                 if (need_butler) {
 755                         _butler->summon ();
 756                 }
 757
 758                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 759
 760                 if (frames_moved < 0) {
 761                         decrement_transport_position (-frames_moved);
 762                 } else {
 763                         increment_transport_position (frames_moved);
 764                 }
 765
 766                 framepos_t stop_limit;
 767
 768                 if (actively_recording()) {
 769                         stop_limit = max_framepos;
 770                 } else {
 771                         if (Config->get_stop_at_session_end()) {
 772                                 stop_limit = current_end_frame();
 773                         } else {
 774                                 stop_limit = max_framepos;
 775                         }
 776                 }
 777
 778                 maybe_stop (stop_limit);
 779         }
 780 }
 781
 782 void
 783 Session::process_without_events (pframes_t nframes)
 784 {
 785         bool session_needs_butler = false;
 786         framepos_t stop_limit;
 787         framecnt_t frames_moved;
 788
 789         if (!process_can_proceed()) {
 790                 _silent = true;
 791                 return;
 792         }
 793
 794         if (!_exporting && _slave) {
 795                 if (!follow_slave (nframes)) {
 796                         return;
 797                 }
 798         }
 799
 800         if (_transport_speed == 0) {
 801                 fail_roll (nframes);
 802                 return;
 803         }
 804
 805         if (_transport_speed == 1.0) {
 806                 frames_moved = (framecnt_t) nframes;
 807         } else {
 808                 interpolation.set_target_speed (fabs(_target_transport_speed));
 809                 interpolation.set_speed (fabs(_transport_speed));
 810                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 811         }
 812
 813         if (!_exporting && !timecode_transmission_suspended()) {
 814                 send_midi_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, nframes);
 815         }
 816
 817         if (actively_recording()) {
 818                 stop_limit = max_framepos;
 819         } else {
 820                 if (Config->get_stop_at_session_end()) {
 821                         stop_limit = current_end_frame();
 822                 } else {
 823                         stop_limit = max_framepos;
 824                 }
 825         }
 826
 827         if (maybe_stop (stop_limit)) {
 828                 fail_roll (nframes);
 829                 return;
 830         }
 831
 832         if (maybe_sync_start (nframes)) {
 833                 return;
 834         }
 835
 836         click (_transport_frame, nframes);
 837
 838         if (process_routes (nframes, session_needs_butler)) {
 839                 fail_roll (nframes);
 840                 return;
 841         }
 842
 843         get_track_statistics ();
 844
 845         /* XXX: I'm not sure whether this is correct, but at least it
 846            matches process_with_events, so that this new frames_moved
 847            is -ve when transport speed is -ve.  This means that the
 848            transport position is updated correctly when we are in
 849            reverse.  It seems a bit wrong that we're not using the
 850            interpolator to compute this.
 851         */
 852
 853         frames_moved = (framecnt_t) floor (_transport_speed * nframes);
 854
 855         if (frames_moved < 0) {
 856                 decrement_transport_position (-frames_moved);
 857         } else {
 858                 increment_transport_position (frames_moved);
 859         }
 860
 861         maybe_stop (stop_limit);
 862         check_declick_out ();
 863
 864         if (session_needs_butler) {
 865                 _butler->summon ();
 866         }
 867 }
 868
 869 /** Process callback used when the auditioner is active.
 870  * @param nframes number of frames to process.
 871  */
 872 void
 873 Session::process_audition (pframes_t nframes)
 874 {
 875         SessionEvent* ev;
 876         boost::shared_ptr<RouteList> r = routes.reader ();
 877
 878         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 879                 if (!(*i)->is_hidden()) {
 880                         (*i)->silence (nframes);
 881                 }
 882         }
 883
 884         /* run the auditioner, and if it says we need butler service, ask for it */
 885
 886         if (auditioner->play_audition (nframes) > 0) {
 887                 _butler->summon ();
 888         }
 889
 890         /* if using a monitor section, run it because otherwise we don't hear anything */
 891
 892         if (auditioner->needs_monitor()) {
 893                 _monitor_out->passthru (_transport_frame, _transport_frame + nframes, nframes, false);
 894         }
 895
 896         /* handle pending events */
 897
 898         while (pending_events.read (&ev, 1) == 1) {
 899                 merge_event (ev);
 900         }
 901
 902         /* if we are not in the middle of a state change,
 903            and there are immediate events queued up,
 904            process them.
 905         */
 906
 907         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 908                 SessionEvent *ev = immediate_events.front ();
 909                 immediate_events.pop_front ();
 910                 process_event (ev);
 911         }
 912
 913         if (!auditioner->auditioning()) {
 914                 /* auditioner no longer active, so go back to the normal process callback */
 915                 process_function = &Session::process_with_events;
 916         }
 917 }
 918
 919 bool
 920 Session::maybe_sync_start (pframes_t & nframes)
 921 {
 922         pframes_t sync_offset;
 923
 924         if (!waiting_for_sync_offset) {
 925                 return false;
 926         }
 927
 928         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 929
 930                 /* generate silence up to the sync point, then
 931                    adjust nframes + offset to reflect whatever
 932                    is left to do.
 933                 */
 934
 935                 no_roll (sync_offset);
 936                 nframes -= sync_offset;
 937                 AudioPort::increment_port_offset (sync_offset);
 938                 waiting_for_sync_offset = false;
 939
 940                 if (nframes == 0) {
 941                         return true; // done, nothing left to process
 942                 }
 943
 944         } else {
 945
 946                 /* sync offset point is not within this process()
 947                    cycle, so just generate silence. and don't bother
 948                    with any fancy stuff here, just the minimal silence.
 949                 */
 950
 951                 _silent = true;
 952
 953                 if (Config->get_locate_while_waiting_for_sync()) {
 954                         if (micro_locate (nframes)) {
 955                                 /* XXX ERROR !!! XXX */
 956                         }
 957                 }
 958
 959                 return true; // done, nothing left to process
 960         }
 961
 962         return false;
 963 }
 964
 965 void
 966 Session::queue_event (SessionEvent* ev)
 967 {
 968         if (_state_of_the_state & Deletion) {
 969                 return;
 970         } else if (_state_of_the_state & Loading) {
 971                 merge_event (ev);
 972         } else {
 973                 pending_events.write (&ev, 1);
 974         }
 975 }
 976
 977 void
 978 Session::set_next_event ()
 979 {
 980         if (events.empty()) {
 981                 next_event = events.end();
 982                 return;
 983         }
 984
 985         if (next_event == events.end()) {
 986                 next_event = events.begin();
 987         }
 988
 989         if ((*next_event)->action_frame > _transport_frame) {
 990                 next_event = events.begin();
 991         }
 992
 993         for (; next_event != events.end(); ++next_event) {
 994                 if ((*next_event)->action_frame >= _transport_frame) {
 995                         break;
 996                 }
 997         }
 998 }
 999
1000 void
1001 Session::process_event (SessionEvent* ev)
1002 {
1003         bool remove = true;
1004         bool del = true;
1005
1006         /* if we're in the middle of a state change (i.e. waiting
1007            for the butler thread to complete the non-realtime
1008            part of the change), we'll just have to queue this
1009            event for a time when the change is complete.
1010         */
1011
1012         if (non_realtime_work_pending()) {
1013
1014                 /* except locates, which we have the capability to handle */
1015
1016                 if (ev->type != SessionEvent::Locate) {
1017                         immediate_events.insert (immediate_events.end(), ev);
1018                         _remove_event (ev);
1019                         return;
1020                 }
1021         }
1022
1023         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1024
1025         switch (ev->type) {
1026         case SessionEvent::SetLoop:
1027                 set_play_loop (ev->yes_or_no);
1028                 break;
1029
1030         case SessionEvent::AutoLoop:
1031                 if (play_loop) {
1032                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1033                 }
1034                 remove = false;
1035                 del = false;
1036                 break;
1037
1038         case SessionEvent::Locate:
1039                 if (ev->yes_or_no) {
1040                         // cerr << "forced locate to " << ev->target_frame << endl;
1041                         locate (ev->target_frame, false, true, false);
1042                 } else {
1043                         // cerr << "soft locate to " << ev->target_frame << endl;
1044                         start_locate (ev->target_frame, false, true, false);
1045                 }
1046                 _send_timecode_update = true;
1047                 break;
1048
1049         case SessionEvent::LocateRoll:
1050                 if (ev->yes_or_no) {
1051                         // cerr << "forced locate to+roll " << ev->target_frame << endl;
1052                         locate (ev->target_frame, true, true, false);
1053                 } else {
1054                         // cerr << "soft locate to+roll " << ev->target_frame << endl;
1055                         start_locate (ev->target_frame, true, true, false);
1056                 }
1057                 _send_timecode_update = true;
1058                 break;
1059
1060         case SessionEvent::LocateRollLocate:
1061                 // locate is handled by ::request_roll_at_and_return()
1062                 _requested_return_frame = ev->target_frame;
1063                 request_locate (ev->target2_frame, true);
1064                 break;
1065
1066
1067         case SessionEvent::SetTransportSpeed:
1068                 set_transport_speed (ev->speed, ev->yes_or_no, ev->second_yes_or_no);
1069                 break;
1070
1071         case SessionEvent::PunchIn:
1072                 // cerr << "PunchIN at " << transport_frame() << endl;
1073                 if (config.get_punch_in() && record_status() == Enabled) {
1074                         enable_record ();
1075                 }
1076                 remove = false;
1077                 del = false;
1078                 break;
1079
1080         case SessionEvent::PunchOut:
1081                 // cerr << "PunchOUT at " << transport_frame() << endl;
1082                 if (config.get_punch_out()) {
1083                         step_back_from_record ();
1084                 }
1085                 remove = false;
1086                 del = false;
1087                 break;
1088
1089         case SessionEvent::StopOnce:
1090                 if (!non_realtime_work_pending()) {
1091                         stop_transport (ev->yes_or_no);
1092                         _clear_event_type (SessionEvent::StopOnce);
1093                 }
1094                 remove = false;
1095                 del = false;
1096                 break;
1097
1098         case SessionEvent::RangeStop:
1099                 if (!non_realtime_work_pending()) {
1100                         stop_transport (ev->yes_or_no);
1101                 }
1102                 remove = false;
1103                 del = false;
1104                 break;
1105
1106         case SessionEvent::RangeLocate:
1107                 start_locate (ev->target_frame, true, true, false);
1108                 remove = false;
1109                 del = false;
1110                 break;
1111
1112         case SessionEvent::Overwrite:
1113                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1114                 break;
1115
1116         case SessionEvent::SetTrackSpeed:
1117                 set_track_speed (static_cast<Track*> (ev->ptr), ev->speed);
1118                 break;
1119
1120         case SessionEvent::SetSyncSource:
1121                 use_sync_source (ev->slave);
1122                 break;
1123
1124         case SessionEvent::Audition:
1125                 set_audition (ev->region);
1126                 // drop reference to region
1127                 ev->region.reset ();
1128                 break;
1129
1130         case SessionEvent::InputConfigurationChange:
1131                 add_post_transport_work (PostTransportInputChange);
1132                 _butler->schedule_transport_work ();
1133                 break;
1134
1135         case SessionEvent::SetPlayAudioRange:
1136                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1137                 break;
1138
1139         case SessionEvent::RealTimeOperation:
1140                 process_rtop (ev);
1141                 del = false; // other side of RT request needs to clean up
1142                 break;
1143
1144         case SessionEvent::AdjustPlaybackBuffering:
1145                 schedule_playback_buffering_adjustment ();
1146                 break;
1147
1148         case SessionEvent::AdjustCaptureBuffering:
1149                 schedule_capture_buffering_adjustment ();
1150                 break;
1151
1152         case SessionEvent::SetTimecodeTransmission:
1153                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1154                 break;
1155
1156         default:
1157           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1158                 /*NOTREACHED*/
1159                 break;
1160         };
1161
1162         if (remove) {
1163                 del = del && !_remove_event (ev);
1164         }
1165
1166         if (del) {
1167                 delete ev;
1168         }
1169 }
1170