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/audio_diskstream.h"
  32 #include "ardour/audioengine.h"
  33 #include "ardour/auditioner.h"
  34 #include "ardour/butler.h"
  35 #include "ardour/debug.h"
  36 #include "ardour/session.h"
  37 #include "ardour/slave.h"
  38 #include "ardour/timestamps.h"
  39
  40 #include "midi++/manager.h"
  41
  42 #include "i18n.h"
  43
  44 using namespace ARDOUR;
  45 using namespace PBD;
  46 using namespace std;
  47
  48 /** Called by the audio engine when there is work to be done with JACK.
  49  * @param nframes Number of frames to process.
  50  */
  51 void
  52 Session::process (nframes_t nframes)
  53 {
  54         MIDI::Manager::instance()->cycle_start(nframes);
  55
  56         _silent = false;
  57
  58         if (processing_blocked()) {
  59                 _silent = true;
  60                 return;
  61         }
  62
  63         if (non_realtime_work_pending()) {
  64                 if (!_butler->transport_work_requested ()) {
  65                         post_transport ();
  66                 }
  67         }
  68
  69         (this->*process_function) (nframes);
  70
  71         // the ticker is for sending time information like MidiClock
  72         nframes_t transport_frames = transport_frame();
  73         BBT_Time  transport_bbt;
  74         bbt_time(transport_frames, transport_bbt);
  75         Timecode::Time transport_timecode;
  76         timecode_time(transport_frames, transport_timecode);
  77         tick (transport_frames, transport_bbt, transport_timecode); /* EMIT SIGNAL */
  78
  79         SendFeedback (); /* EMIT SIGNAL */
  80
  81         MIDI::Manager::instance()->cycle_end();
  82 }
  83
  84 void
  85 Session::prepare_diskstreams ()
  86 {
  87         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
  88         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
  89                 (*i)->prepare ();
  90         }
  91 }
  92
  93 int
  94 Session::fail_roll (nframes_t nframes)
  95 {
  96         return no_roll (nframes);
  97 }
  98
  99 int
 100 Session::no_roll (nframes_t nframes)
 101 {
 102         nframes_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 103         int ret = 0;
 104         bool declick = get_transport_declick_required();
 105         boost::shared_ptr<RouteList> r = routes.reader ();
 106
 107         if (_click_io) {
 108                 _click_io->silence (nframes);
 109         }
 110
 111         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 112
 113                 if ((*i)->is_hidden()) {
 114                         continue;
 115                 }
 116
 117                 (*i)->set_pending_declick (declick);
 118
 119                 if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending(),
 120                                    actively_recording(), declick)) {
 121                         error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 122                         ret = -1;
 123                         break;
 124                 }
 125         }
 126
 127         return ret;
 128 }
 129
 130 int
 131 Session::process_routes (nframes_t nframes)
 132 {
 133         bool record_active;
 134         int  declick = get_transport_declick_required();
 135         bool rec_monitors = get_rec_monitors_input();
 136         boost::shared_ptr<RouteList> r = routes.reader ();
 137
 138         if (transport_sub_state & StopPendingCapture) {
 139                 /* force a declick out */
 140                 declick = -1;
 141         }
 142
 143         record_active = actively_recording(); // || (get_record_enabled() && get_punch_in());
 144
 145         const nframes_t start_frame = _transport_frame;
 146         const nframes_t end_frame = _transport_frame + (nframes_t)floor(nframes * _transport_speed);
 147
 148         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 149
 150                 int ret;
 151
 152                 if ((*i)->is_hidden()) {
 153                         continue;
 154                 }
 155
 156                 (*i)->set_pending_declick (declick);
 157
 158                 if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, record_active, rec_monitors)) < 0) {
 159
 160                         /* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
 161                            and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 162                            call path, so make sure we release any outstanding locks here before we return failure.
 163                         */
 164
 165                         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 166                         for (DiskstreamList::iterator ids = dsl->begin(); ids != dsl->end(); ++ids) {
 167                                 (*ids)->recover ();
 168                         }
 169
 170                         stop_transport ();
 171                         return -1;
 172                 }
 173         }
 174
 175         return 0;
 176 }
 177
 178 int
 179 Session::silent_process_routes (nframes_t nframes)
 180 {
 181         bool record_active = actively_recording();
 182         int  declick = get_transport_declick_required();
 183         bool rec_monitors = get_rec_monitors_input();
 184         boost::shared_ptr<RouteList> r = routes.reader ();
 185
 186         if (transport_sub_state & StopPendingCapture) {
 187                 /* force a declick out */
 188                 declick = -1;
 189         }
 190
 191         const nframes_t start_frame = _transport_frame;
 192         const nframes_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 193
 194         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 195
 196                 int ret;
 197
 198                 if ((*i)->is_hidden()) {
 199                         continue;
 200                 }
 201
 202                 if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, record_active, rec_monitors)) < 0) {
 203
 204                         /* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
 205                            and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 206                            call path, so make sure we release any outstanding locks here before we return failure.
 207                         */
 208
 209                         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 210                         for (DiskstreamList::iterator ids = dsl->begin(); ids != dsl->end(); ++ids) {
 211                                 (*ids)->recover ();
 212                         }
 213
 214                         stop_transport ();
 215                         return -1;
 216                 }
 217         }
 218
 219         return 0;
 220 }
 221
 222 void
 223 Session::commit_diskstreams (nframes_t nframes, bool &needs_butler)
 224 {
 225         int dret;
 226         float pworst = 1.0f;
 227         float cworst = 1.0f;
 228
 229         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 230         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 231
 232                 if ((*i)->hidden()) {
 233                         continue;
 234                 }
 235
 236                 /* force all diskstreams not handled by a Route to call do their stuff.
 237                    Note: the diskstreams that were handled by a route will just return zero
 238                    from this call, because they know they were processed. So in fact, this
 239                    also runs commit() for every diskstream.
 240                  */
 241
 242                 if ((dret = (*i)->process (_transport_frame, nframes, actively_recording(), get_rec_monitors_input())) == 0) {
 243                         if ((*i)->commit (nframes)) {
 244                                 needs_butler = true;
 245                         }
 246
 247                 } else if (dret < 0) {
 248                         (*i)->recover();
 249                 }
 250
 251                 pworst = min (pworst, (*i)->playback_buffer_load());
 252                 cworst = min (cworst, (*i)->capture_buffer_load());
 253         }
 254
 255         uint32_t pmin = g_atomic_int_get (&_playback_load);
 256         uint32_t pminold = g_atomic_int_get (&_playback_load_min);
 257         uint32_t cmin = g_atomic_int_get (&_capture_load);
 258         uint32_t cminold = g_atomic_int_get (&_capture_load_min);
 259
 260         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 261         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 262         g_atomic_int_set (&_playback_load_min, min (pmin, pminold));
 263         g_atomic_int_set (&_capture_load_min, min (cmin, cminold));
 264
 265         if (actively_recording()) {
 266                 set_dirty();
 267         }
 268 }
 269
 270 /** Process callback used when the auditioner is not active */
 271 void
 272 Session::process_with_events (nframes_t nframes)
 273 {
 274         SessionEvent*         ev;
 275         nframes_t      this_nframes;
 276         nframes_t      end_frame;
 277         bool           session_needs_butler = false;
 278         nframes_t      stop_limit;
 279         long           frames_moved;
 280
 281         /* make sure the auditioner is silent */
 282
 283         if (auditioner) {
 284                 auditioner->silence (nframes);
 285         }
 286
 287         /* handle any pending events */
 288
 289         while (pending_events.read (&ev, 1) == 1) {
 290                 merge_event (ev);
 291         }
 292
 293         /* if we are not in the middle of a state change,
 294            and there are immediate events queued up,
 295            process them.
 296         */
 297
 298         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 299                 SessionEvent *ev = immediate_events.front ();
 300                 immediate_events.pop_front ();
 301                 process_event (ev);
 302         }
 303
 304         /* Events caused a transport change, send an MTC Full Frame (Timecode) message.
 305          * This is sent whether rolling or not, to give slaves an idea of ardour time
 306          * on locates (and allow slow slaves to position and prepare for rolling)
 307          */
 308         if (_send_timecode_update) {
 309                 send_full_time_code(nframes);
 310                 deliver_mmc (MIDI::MachineControl::cmdLocate, _transport_frame);
 311         }
 312
 313         if (!process_can_proceed()) {
 314                 _silent = true;
 315                 return;
 316         }
 317
 318         if (events.empty() || next_event == events.end()) {
 319                 process_without_events (nframes);
 320                 return;
 321         }
 322
 323         if (_transport_speed == 1.0) {
 324                 frames_moved = (long) nframes;
 325         } else {
 326                 interpolation.set_target_speed (fabs(_target_transport_speed));
 327                 interpolation.set_speed (fabs(_transport_speed));
 328                 frames_moved = (long) interpolation.interpolate (0, nframes, 0, 0);
 329         }
 330
 331         end_frame = _transport_frame + (nframes_t)frames_moved;
 332
 333         {
 334                 SessionEvent* this_event;
 335                 Events::iterator the_next_one;
 336
 337                 if (!process_can_proceed()) {
 338                         _silent = true;
 339                         return;
 340                 }
 341
 342                 if (!_exporting && _slave) {
 343                         if (!follow_slave (nframes)) {
 344                                 return;
 345                         }
 346                 }
 347
 348                 if (_transport_speed == 0) {
 349                         no_roll (nframes);
 350                         return;
 351                 }
 352
 353                 if (!_exporting) {
 354                         send_midi_time_code_for_cycle (nframes);
 355                 }
 356
 357                 if (actively_recording()) {
 358                         stop_limit = max_frames;
 359                 } else {
 360
 361                         if (Config->get_stop_at_session_end()) {
 362                                 stop_limit = current_end_frame();
 363                         } else {
 364                                 stop_limit = max_frames;
 365                         }
 366                 }
 367
 368                 if (maybe_stop (stop_limit)) {
 369                         no_roll (nframes);
 370                         return;
 371                 }
 372
 373                 this_event = *next_event;
 374                 the_next_one = next_event;
 375                 ++the_next_one;
 376
 377                 /* yes folks, here it is, the actual loop where we really truly
 378                    process some audio
 379                 */
 380
 381                 while (nframes) {
 382
 383                         this_nframes = nframes; /* real (jack) time relative */
 384                         frames_moved = (long) floor (_transport_speed * nframes); /* transport relative */
 385
 386                         /* running an event, position transport precisely to its time */
 387                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 388                                 /* this isn't quite right for reverse play */
 389                                 frames_moved = (long) (this_event->action_frame - _transport_frame);
 390                                 this_nframes = (nframes_t) abs( floor(frames_moved / _transport_speed) );
 391                         }
 392
 393                         if (this_nframes) {
 394
 395                                 click (_transport_frame, this_nframes);
 396
 397                                 /* now process frames between now and the first event in this block */
 398                                 prepare_diskstreams ();
 399
 400                                 if (process_routes (this_nframes)) {
 401                                         fail_roll (nframes);
 402                                         return;
 403                                 }
 404
 405                                 commit_diskstreams (this_nframes, session_needs_butler);
 406
 407                                 nframes -= this_nframes;
 408
 409                                 if (frames_moved < 0) {
 410                                         decrement_transport_position (-frames_moved);
 411                                 } else {
 412                                         increment_transport_position (frames_moved);
 413                                 }
 414
 415                                 maybe_stop (stop_limit);
 416                                 check_declick_out ();
 417                         }
 418
 419                         _engine.split_cycle (this_nframes);
 420
 421                         /* now handle this event and all others scheduled for the same time */
 422
 423                         while (this_event && this_event->action_frame == _transport_frame) {
 424                                 process_event (this_event);
 425
 426                                 if (the_next_one == events.end()) {
 427                                         this_event = 0;
 428                                 } else {
 429                                         this_event = *the_next_one;
 430                                         ++the_next_one;
 431                                 }
 432                         }
 433
 434                         /* if an event left our state changing, do the right thing */
 435
 436                         if (nframes && non_realtime_work_pending()) {
 437                                 no_roll (nframes);
 438                                 break;
 439                         }
 440
 441                         /* this is necessary to handle the case of seamless looping */
 442                         end_frame = _transport_frame + (nframes_t) floor (nframes * _transport_speed);
 443
 444                 }
 445
 446                 set_next_event ();
 447
 448         } /* implicit release of route lock */
 449
 450         if (session_needs_butler) {
 451                 _butler->summon ();
 452         }
 453 }
 454
 455 void
 456 Session::reset_slave_state ()
 457 {
 458         average_slave_delta = 1800;
 459         delta_accumulator_cnt = 0;
 460         have_first_delta_accumulator = false;
 461         _slave_state = Stopped;
 462 }
 463
 464 bool
 465 Session::transport_locked () const
 466 {
 467         Slave* sl = _slave;
 468
 469         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 470                 return true;
 471         }
 472
 473         return false;
 474 }
 475
 476 bool
 477 Session::follow_slave (nframes_t nframes)
 478 {
 479         double slave_speed;
 480         nframes64_t slave_transport_frame;
 481         nframes_t this_delta;
 482         int dir;
 483
 484         if (!_slave->ok()) {
 485                 stop_transport ();
 486                 config.set_external_sync (false);
 487                 goto noroll;
 488         }
 489
 490         _slave->speed_and_position (slave_speed, slave_transport_frame);
 491
 492         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 493
 494         if (!_slave->locked()) {
 495                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 496                 goto noroll;
 497         }
 498
 499         if (slave_transport_frame > _transport_frame) {
 500                 this_delta = slave_transport_frame - _transport_frame;
 501                 dir = 1;
 502         } else {
 503                 this_delta = _transport_frame - slave_transport_frame;
 504                 dir = -1;
 505         }
 506
 507         if (_slave->starting()) {
 508                 slave_speed = 0.0f;
 509         }
 510
 511         if (_slave->is_always_synced() || config.get_timecode_source_is_synced()) {
 512
 513                 /* if the TC source is synced, then we assume that its
 514                    speed is binary: 0.0 or 1.0
 515                 */
 516
 517                 if (slave_speed != 0.0f) {
 518                         slave_speed = 1.0f;
 519                 }
 520
 521         } else {
 522
 523                 /* if we are chasing and the average delta between us and the
 524                    master gets too big, we want to switch to silent
 525                    motion. so keep track of that here.
 526                 */
 527
 528                 if (_slave_state == Running) {
 529                         calculate_moving_average_of_slave_delta(dir, this_delta);
 530                 }
 531         }
 532
 533         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 534
 535         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 536                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 537
 538
 539         if (_slave_state == Running && !_slave->is_always_synced() && !config.get_timecode_source_is_synced()) {
 540
 541                 if (_transport_speed != 0.0f) {
 542
 543                         /*
 544                            note that average_dir is +1 or -1
 545                         */
 546
 547                         float delta;
 548
 549                         if (average_slave_delta == 0) {
 550                                 delta = this_delta;
 551                                 delta *= dir;
 552                         } else {
 553                                 delta = average_slave_delta;
 554                                 delta *= average_dir;
 555                         }
 556
 557 #ifndef NDEBUG
 558                         if (slave_speed != 0.0) {
 559                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 560                                                                            (int) (dir * this_delta),
 561                                                                            slave_speed,
 562                                                                            _transport_speed,
 563                                                                            _transport_frame,
 564                                                                            slave_transport_frame,
 565                                                                            average_slave_delta));
 566                         }
 567 #endif
 568
 569                         if (_slave->give_slave_full_control_over_transport_speed()) {
 570                                 set_transport_speed (slave_speed, false, false);
 571                                 //std::cout << "set speed = " << slave_speed << "\n";
 572                         } else {
 573                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 574                                 request_transport_speed (adjusted_speed);
 575                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 576                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 577                                                                            slave_speed));
 578                         }
 579
 580 #if 0
 581                         if (abs(average_slave_delta) > _slave->resolution()) {
 582                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 583                                 goto silent_motion;
 584                         }
 585 #endif
 586                 }
 587         }
 588
 589
 590         if (_slave_state == Running && !non_realtime_work_pending()) {
 591                 /* speed is set, we're locked, and good to go */
 592                 return true;
 593         }
 594
 595   silent_motion:
 596         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 597         follow_slave_silently (nframes, slave_speed);
 598
 599   noroll:
 600         /* don't move at all */
 601         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 602         no_roll (nframes);
 603         return false;
 604 }
 605
 606 void
 607 Session::calculate_moving_average_of_slave_delta(int dir, nframes_t this_delta)
 608 {
 609         if (delta_accumulator_cnt >= delta_accumulator_size) {
 610                 have_first_delta_accumulator = true;
 611                 delta_accumulator_cnt = 0;
 612         }
 613
 614         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 615                 delta_accumulator[delta_accumulator_cnt++] = long(dir) * long(this_delta);
 616         }
 617
 618         if (have_first_delta_accumulator) {
 619                 average_slave_delta = 0L;
 620                 for (int i = 0; i < delta_accumulator_size; ++i) {
 621                         average_slave_delta += delta_accumulator[i];
 622                 }
 623                 average_slave_delta /= long(delta_accumulator_size);
 624                 if (average_slave_delta < 0L) {
 625                         average_dir = -1;
 626                         average_slave_delta = abs(average_slave_delta);
 627                 } else {
 628                         average_dir = 1;
 629                 }
 630         }
 631 }
 632
 633 void
 634 Session::track_slave_state (float slave_speed, nframes_t slave_transport_frame, nframes_t this_delta)
 635 {
 636         if (slave_speed != 0.0f) {
 637
 638                 /* slave is running */
 639
 640                 switch (_slave_state) {
 641                 case Stopped:
 642                         if (_slave->requires_seekahead()) {
 643                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 644                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 645                                 /* we can call locate() here because we are in process context */
 646                                 locate (slave_wait_end, false, false);
 647                                 _slave_state = Waiting;
 648
 649                         } else {
 650
 651                                 _slave_state = Running;
 652
 653                                 Location* al = _locations.auto_loop_location();
 654
 655                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 656                                         // cancel looping
 657                                         request_play_loop(false);
 658                                 }
 659
 660                                 if (slave_transport_frame != _transport_frame) {
 661                                         locate (slave_transport_frame, false, false);
 662                                 }
 663                         }
 664                         break;
 665
 666                 case Waiting:
 667                 default:
 668                         break;
 669                 }
 670
 671                 if (_slave_state == Waiting) {
 672
 673                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 674
 675                         if (slave_transport_frame >= slave_wait_end) {
 676
 677                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 678
 679                                 _slave_state = Running;
 680
 681                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 682                                    precisely with the master.
 683                                 */
 684
 685
 686                                 bool ok = true;
 687                                 nframes_t frame_delta = slave_transport_frame - _transport_frame;
 688
 689                                 boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 690
 691                                 for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 692                                         if (!(*i)->can_internal_playback_seek (frame_delta)) {
 693                                                 ok = false;
 694                                                 break;
 695                                         }
 696                                 }
 697
 698                                 if (ok) {
 699                                         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 700                                                 (*i)->internal_playback_seek (frame_delta);
 701                                         }
 702                                         _transport_frame += frame_delta;
 703
 704                                 } else {
 705                                         cerr << "cannot micro-seek\n";
 706                                         /* XXX what? */
 707                                 }
 708
 709                                 memset (delta_accumulator, 0, sizeof (long) * delta_accumulator_size);
 710                                 average_slave_delta = 0L;
 711                                 this_delta = 0;
 712                         }
 713                 }
 714
 715                 if (_slave_state == Running && _transport_speed == 0.0f) {
 716                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 717                         start_transport ();
 718                 }
 719
 720         } else { // slave_speed is 0
 721
 722                 /* slave has stopped */
 723
 724                 if (_transport_speed != 0.0f) {
 725                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 726                         stop_transport();
 727                 }
 728
 729                 if (slave_transport_frame != _transport_frame) {
 730                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 731                         force_locate (slave_transport_frame, false);
 732                 }
 733
 734                 _slave_state = Stopped;
 735         }
 736 }
 737
 738 void
 739 Session::follow_slave_silently (nframes_t nframes, float slave_speed)
 740 {
 741         if (slave_speed && _transport_speed) {
 742
 743                 /* something isn't right, but we should move with the master
 744                    for now.
 745                 */
 746
 747                 bool need_butler;
 748
 749                 prepare_diskstreams ();
 750                 silent_process_routes (nframes);
 751                 commit_diskstreams (nframes, need_butler);
 752
 753                 if (need_butler) {
 754                         _butler->summon ();
 755                 }
 756
 757                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 758
 759                 if (frames_moved < 0) {
 760                         decrement_transport_position (-frames_moved);
 761                 } else {
 762                         increment_transport_position (frames_moved);
 763                 }
 764
 765                 nframes_t stop_limit;
 766
 767                 if (actively_recording()) {
 768                         stop_limit = max_frames;
 769                 } else {
 770                         if (Config->get_stop_at_session_end()) {
 771                                 stop_limit = current_end_frame();
 772                         } else {
 773                                 stop_limit = max_frames;
 774                         }
 775                 }
 776
 777                 maybe_stop (stop_limit);
 778         }
 779 }
 780
 781 void
 782 Session::process_without_events (nframes_t nframes)
 783 {
 784         bool session_needs_butler = false;
 785         nframes_t stop_limit;
 786         long frames_moved;
 787
 788         if (!process_can_proceed()) {
 789                 _silent = true;
 790                 return;
 791         }
 792
 793         if (!_exporting && _slave) {
 794                 if (!follow_slave (nframes)) {
 795                         return;
 796                 }
 797         }
 798
 799         if (_transport_speed == 0) {
 800                 fail_roll (nframes);
 801                 return;
 802         }
 803
 804         if (!_exporting) {
 805                 send_midi_time_code_for_cycle (nframes);
 806         }
 807
 808         if (actively_recording()) {
 809                 stop_limit = max_frames;
 810         } else {
 811                 if (Config->get_stop_at_session_end()) {
 812                         stop_limit = current_end_frame();
 813                 } else {
 814                         stop_limit = max_frames;
 815                 }
 816         }
 817
 818         if (maybe_stop (stop_limit)) {
 819                 fail_roll (nframes);
 820                 return;
 821         }
 822
 823         if (maybe_sync_start (nframes)) {
 824                 return;
 825         }
 826
 827         click (_transport_frame, nframes);
 828
 829         prepare_diskstreams ();
 830
 831         if (_transport_speed == 1.0) {
 832                 frames_moved = (long) nframes;
 833         } else {
 834                 interpolation.set_target_speed (fabs(_target_transport_speed));
 835                 interpolation.set_speed (fabs(_transport_speed));
 836                 frames_moved = (long) interpolation.interpolate (0, nframes, 0, 0);
 837         }
 838
 839         if (process_routes (nframes)) {
 840                 fail_roll (nframes);
 841                 return;
 842         }
 843
 844         commit_diskstreams (nframes, session_needs_butler);
 845
 846         if (frames_moved < 0) {
 847                 decrement_transport_position (-frames_moved);
 848         } else {
 849                 increment_transport_position (frames_moved);
 850         }
 851
 852         maybe_stop (stop_limit);
 853         check_declick_out ();
 854
 855         if (session_needs_butler) {
 856                 _butler->summon ();
 857         }
 858 }
 859
 860 /** Process callback used when the auditioner is active.
 861  * @param nframes number of frames to process.
 862  */
 863 void
 864 Session::process_audition (nframes_t nframes)
 865 {
 866         SessionEvent* ev;
 867         boost::shared_ptr<RouteList> r = routes.reader ();
 868
 869         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 870                 if (!(*i)->is_hidden()) {
 871                         (*i)->silence (nframes);
 872                 }
 873         }
 874
 875         /* run the auditioner, and if it says we need butler service, ask for it */
 876
 877         if (auditioner->play_audition (nframes) > 0) {
 878                 _butler->summon ();
 879         }
 880
 881         /* handle pending events */
 882
 883         while (pending_events.read (&ev, 1) == 1) {
 884                 merge_event (ev);
 885         }
 886
 887         /* if we are not in the middle of a state change,
 888            and there are immediate events queued up,
 889            process them.
 890         */
 891
 892         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 893                 SessionEvent *ev = immediate_events.front ();
 894                 immediate_events.pop_front ();
 895                 process_event (ev);
 896         }
 897
 898         if (!auditioner->active()) {
 899                 /* auditioner no longer active, so go back to the normal process callback */
 900                 process_function = &Session::process_with_events;
 901         }
 902 }
 903
 904 bool
 905 Session::maybe_sync_start (nframes_t& nframes)
 906 {
 907         nframes_t sync_offset;
 908
 909         if (!waiting_for_sync_offset) {
 910                 return false;
 911         }
 912
 913         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 914
 915                 /* generate silence up to the sync point, then
 916                    adjust nframes + offset to reflect whatever
 917                    is left to do.
 918                 */
 919
 920                 no_roll (sync_offset);
 921                 nframes -= sync_offset;
 922                 Port::increment_port_offset (sync_offset);
 923                 waiting_for_sync_offset = false;
 924
 925                 if (nframes == 0) {
 926                         return true; // done, nothing left to process
 927                 }
 928
 929         } else {
 930
 931                 /* sync offset point is not within this process()
 932                    cycle, so just generate silence. and don't bother
 933                    with any fancy stuff here, just the minimal silence.
 934                 */
 935
 936                 _silent = true;
 937
 938                 if (Config->get_locate_while_waiting_for_sync()) {
 939                         if (micro_locate (nframes)) {
 940                                 /* XXX ERROR !!! XXX */
 941                         }
 942                 }
 943
 944                 return true; // done, nothing left to process
 945         }
 946
 947         return false;
 948 }
 949
 950 void
 951 Session::queue_event (SessionEvent* ev)
 952 {
 953         if (_state_of_the_state & Deletion) {
 954                 return;
 955         } else if (_state_of_the_state & Loading) {
 956                 merge_event (ev);
 957         } else {
 958                 pending_events.write (&ev, 1);
 959         }
 960 }
 961
 962 void
 963 Session::set_next_event ()
 964 {
 965         if (events.empty()) {
 966                 next_event = events.end();
 967                 return;
 968         }
 969
 970         if (next_event == events.end()) {
 971                 next_event = events.begin();
 972         }
 973
 974         if ((*next_event)->action_frame > _transport_frame) {
 975                 next_event = events.begin();
 976         }
 977
 978         for (; next_event != events.end(); ++next_event) {
 979                 if ((*next_event)->action_frame >= _transport_frame) {
 980                         break;
 981                 }
 982         }
 983 }
 984
 985 void
 986 Session::process_event (SessionEvent* ev)
 987 {
 988         bool remove = true;
 989         bool del = true;
 990
 991         /* if we're in the middle of a state change (i.e. waiting
 992            for the butler thread to complete the non-realtime
 993            part of the change), we'll just have to queue this
 994            event for a time when the change is complete.
 995         */
 996
 997         if (non_realtime_work_pending()) {
 998
 999                 /* except locates, which we have the capability to handle */
1000
1001                 if (ev->type != SessionEvent::Locate) {
1002                         immediate_events.insert (immediate_events.end(), ev);
1003                         _remove_event (ev);
1004                         return;
1005                 }
1006         }
1007
1008         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1009
1010         switch (ev->type) {
1011         case SessionEvent::SetLoop:
1012                 set_play_loop (ev->yes_or_no);
1013                 break;
1014
1015         case SessionEvent::AutoLoop:
1016                 if (play_loop) {
1017                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1018                 }
1019                 remove = false;
1020                 del = false;
1021                 break;
1022
1023         case SessionEvent::Locate:
1024                 if (ev->yes_or_no) {
1025                         // cerr << "forced locate to " << ev->target_frame << endl;
1026                         locate (ev->target_frame, false, true, false);
1027                 } else {
1028                         // cerr << "soft locate to " << ev->target_frame << endl;
1029                         start_locate (ev->target_frame, false, true, false);
1030                 }
1031                 _send_timecode_update = true;
1032                 break;
1033
1034         case SessionEvent::LocateRoll:
1035                 if (ev->yes_or_no) {
1036                         // cerr << "forced locate to+roll " << ev->target_frame << endl;
1037                         locate (ev->target_frame, true, true, false);
1038                 } else {
1039                         // cerr << "soft locate to+roll " << ev->target_frame << endl;
1040                         start_locate (ev->target_frame, true, true, false);
1041                 }
1042                 _send_timecode_update = true;
1043                 break;
1044
1045         case SessionEvent::LocateRollLocate:
1046                 // locate is handled by ::request_roll_at_and_return()
1047                 _requested_return_frame = ev->target_frame;
1048                 request_locate (ev->target2_frame, true);
1049                 break;
1050
1051
1052         case SessionEvent::SetTransportSpeed:
1053                 set_transport_speed (ev->speed, ev->yes_or_no, ev->second_yes_or_no);
1054                 break;
1055
1056         case SessionEvent::PunchIn:
1057                 // cerr << "PunchIN at " << transport_frame() << endl;
1058                 if (config.get_punch_in() && record_status() == Enabled) {
1059                         enable_record ();
1060                 }
1061                 remove = false;
1062                 del = false;
1063                 break;
1064
1065         case SessionEvent::PunchOut:
1066                 // cerr << "PunchOUT at " << transport_frame() << endl;
1067                 if (config.get_punch_out()) {
1068                         step_back_from_record ();
1069                 }
1070                 remove = false;
1071                 del = false;
1072                 break;
1073
1074         case SessionEvent::StopOnce:
1075                 if (!non_realtime_work_pending()) {
1076                         stop_transport (ev->yes_or_no);
1077                         _clear_event_type (SessionEvent::StopOnce);
1078                 }
1079                 remove = false;
1080                 del = false;
1081                 break;
1082
1083         case SessionEvent::RangeStop:
1084                 if (!non_realtime_work_pending()) {
1085                         stop_transport (ev->yes_or_no);
1086                 }
1087                 remove = false;
1088                 del = false;
1089                 break;
1090
1091         case SessionEvent::RangeLocate:
1092                 start_locate (ev->target_frame, true, true, false);
1093                 remove = false;
1094                 del = false;
1095                 break;
1096
1097         case SessionEvent::Overwrite:
1098                 overwrite_some_buffers (static_cast<Diskstream*>(ev->ptr));
1099                 break;
1100
1101         case SessionEvent::SetDiskstreamSpeed:
1102                 set_diskstream_speed (static_cast<Diskstream*> (ev->ptr), ev->speed);
1103                 break;
1104
1105         case SessionEvent::SetSyncSource:
1106                 use_sync_source (ev->slave);
1107                 break;
1108
1109         case SessionEvent::Audition:
1110                 set_audition (ev->region);
1111                 // drop reference to region
1112                 ev->region.reset ();
1113                 break;
1114
1115         case SessionEvent::InputConfigurationChange:
1116                 add_post_transport_work (PostTransportInputChange);
1117                 _butler->schedule_transport_work ();
1118                 break;
1119
1120         case SessionEvent::SetPlayAudioRange:
1121                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1122                 break;
1123
1124         case SessionEvent::RealTimeOperation:
1125                 process_rtop (ev);
1126                 del = false; // other side of RT request needs to clean up
1127                 break;
1128
1129         default:
1130           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1131                 /*NOTREACHED*/
1132                 break;
1133         };
1134
1135         if (remove) {
1136                 del = del && !_remove_event (ev);
1137         }
1138
1139         if (del) {
1140                 delete ev;
1141         }
1142 }
1143
1144 void
1145 Session::process_rtop (SessionEvent* ev)
1146 {
1147         ev->rt_slot ();
1148         ev->rt_return (ev);
1149 }