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
  27 #include <glibmm/thread.h>
  28
  29 #include "ardour/ardour.h"
  30 #include "ardour/audio_diskstream.h"
  31 #include "ardour/audioengine.h"
  32 #include "ardour/auditioner.h"
  33 #include "ardour/butler.h"
  34 #include "ardour/debug.h"
  35 #include "ardour/session.h"
  36 #include "ardour/slave.h"
  37 #include "ardour/timestamps.h"
  38
  39 #include "midi++/manager.h"
  40
  41 #include "i18n.h"
  42
  43 using namespace ARDOUR;
  44 using namespace PBD;
  45 using namespace std;
  46
  47 /** Called by the audio engine when there is work to be done with JACK.
  48  * @param nframes Number of frames to process.
  49  */
  50 void
  51 Session::process (nframes_t nframes)
  52 {
  53         // This is no more the appropriate place to call cycle
  54         // start. cycle_start needs to be called at the Route::roll()
  55         // where the signals which we want to mixdown have been calculated.
  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         (this->*process_function) (nframes);
  73
  74         // the ticker is for sending time information like MidiClock
  75         nframes_t transport_frames = transport_frame();
  76         BBT_Time  transport_bbt;
  77         bbt_time(transport_frames, transport_bbt);
  78         Timecode::Time transport_timecode;
  79         timecode_time(transport_frames, transport_timecode);
  80         tick (transport_frames, transport_bbt, transport_timecode); /* EMIT SIGNAL */
  81
  82         SendFeedback (); /* EMIT SIGNAL */
  83
  84         MIDI::Manager::instance()->cycle_end();
  85 }
  86
  87 void
  88 Session::prepare_diskstreams ()
  89 {
  90         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
  91         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
  92                 (*i)->prepare ();
  93         }
  94 }
  95
  96 int
  97 Session::fail_roll (nframes_t nframes)
  98 {
  99         return no_roll (nframes);
 100 }
 101
 102 int
 103 Session::no_roll (nframes_t nframes)
 104 {
 105         nframes_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 106         int ret = 0;
 107         bool declick = get_transport_declick_required();
 108         boost::shared_ptr<RouteList> r = routes.reader ();
 109
 110         if (_click_io) {
 111                 _click_io->silence (nframes);
 112         }
 113
 114         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 115
 116                 if ((*i)->is_hidden()) {
 117                         continue;
 118                 }
 119
 120                 (*i)->set_pending_declick (declick);
 121
 122                 if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending(),
 123                                    actively_recording(), declick)) {
 124                         error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 125                         ret = -1;
 126                         break;
 127                 }
 128         }
 129
 130         return ret;
 131 }
 132
 133 int
 134 Session::process_routes (nframes_t nframes)
 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 nframes_t start_frame = _transport_frame;
 149         const nframes_t end_frame = _transport_frame + (nframes_t)floor(nframes * _transport_speed);
 150
 151         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 152
 153                 int ret;
 154
 155                 if ((*i)->is_hidden()) {
 156                         continue;
 157                 }
 158
 159                 (*i)->set_pending_declick (declick);
 160
 161                 if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, record_active, rec_monitors)) < 0) {
 162
 163                         /* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
 164                            and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 165                            call path, so make sure we release any outstanding locks here before we return failure.
 166                         */
 167
 168                         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 169                         for (DiskstreamList::iterator ids = dsl->begin(); ids != dsl->end(); ++ids) {
 170                                 (*ids)->recover ();
 171                         }
 172
 173                         stop_transport ();
 174                         return -1;
 175                 }
 176         }
 177
 178         return 0;
 179 }
 180
 181 int
 182 Session::silent_process_routes (nframes_t nframes)
 183 {
 184         bool record_active = actively_recording();
 185         int  declick = get_transport_declick_required();
 186         bool rec_monitors = get_rec_monitors_input();
 187         boost::shared_ptr<RouteList> r = routes.reader ();
 188
 189         if (transport_sub_state & StopPendingCapture) {
 190                 /* force a declick out */
 191                 declick = -1;
 192         }
 193
 194         const nframes_t start_frame = _transport_frame;
 195         const nframes_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 196
 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)) < 0) {
 206
 207                         /* we have to do this here. Route::roll() for an AudioTrack will have called AudioDiskstream::process(),
 208                            and the DS will expect AudioDiskstream::commit() to be called. but we're aborting from that
 209                            call path, so make sure we release any outstanding locks here before we return failure.
 210                         */
 211
 212                         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 213                         for (DiskstreamList::iterator ids = dsl->begin(); ids != dsl->end(); ++ids) {
 214                                 (*ids)->recover ();
 215                         }
 216
 217                         stop_transport ();
 218                         return -1;
 219                 }
 220         }
 221
 222         return 0;
 223 }
 224
 225 void
 226 Session::commit_diskstreams (nframes_t nframes, bool &needs_butler)
 227 {
 228         int dret;
 229         float pworst = 1.0f;
 230         float cworst = 1.0f;
 231
 232         boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 233         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 234
 235                 if ((*i)->hidden()) {
 236                         continue;
 237                 }
 238
 239                 /* force all diskstreams not handled by a Route to call do their stuff.
 240                    Note: the diskstreams that were handled by a route will just return zero
 241                    from this call, because they know they were processed. So in fact, this
 242                    also runs commit() for every diskstream.
 243                  */
 244
 245                 if ((dret = (*i)->process (_transport_frame, nframes, actively_recording(), get_rec_monitors_input())) == 0) {
 246                         if ((*i)->commit (nframes)) {
 247                                 needs_butler = true;
 248                         }
 249
 250                 } else if (dret < 0) {
 251                         (*i)->recover();
 252                 }
 253
 254                 pworst = min (pworst, (*i)->playback_buffer_load());
 255                 cworst = min (cworst, (*i)->capture_buffer_load());
 256         }
 257
 258         uint32_t pmin = g_atomic_int_get (&_playback_load);
 259         uint32_t pminold = g_atomic_int_get (&_playback_load_min);
 260         uint32_t cmin = g_atomic_int_get (&_capture_load);
 261         uint32_t cminold = g_atomic_int_get (&_capture_load_min);
 262
 263         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 264         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 265         g_atomic_int_set (&_playback_load_min, min (pmin, pminold));
 266         g_atomic_int_set (&_capture_load_min, min (cmin, cminold));
 267
 268         if (actively_recording()) {
 269                 set_dirty();
 270         }
 271 }
 272
 273 /** Process callback used when the auditioner is not active */
 274 void
 275 Session::process_with_events (nframes_t nframes)
 276 {
 277         Event*         ev;
 278         nframes_t      this_nframes;
 279         nframes_t      end_frame;
 280         bool           session_needs_butler = false;
 281         nframes_t      stop_limit;
 282         long           frames_moved;
 283
 284         /* make sure the auditioner is silent */
 285
 286         if (auditioner) {
 287                 auditioner->silence (nframes);
 288         }
 289
 290         /* handle any pending events */
 291
 292         while (pending_events.read (&ev, 1) == 1) {
 293                 merge_event (ev);
 294         }
 295
 296         /* if we are not in the middle of a state change,
 297            and there are immediate events queued up,
 298            process them.
 299         */
 300
 301         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 302                 Event *ev = immediate_events.front ();
 303                 immediate_events.pop_front ();
 304                 process_event (ev);
 305         }
 306
 307         /* Events caused a transport change, send an MTC Full Frame (Timecode) message.
 308          * This is sent whether rolling or not, to give slaves an idea of ardour time
 309          * on locates (and allow slow slaves to position and prepare for rolling)
 310          */
 311         if (_send_timecode_update) {
 312                 send_full_time_code(nframes);
 313                 deliver_mmc (MIDI::MachineControl::cmdLocate, _transport_frame);
 314         }
 315
 316         if (!process_can_proceed()) {
 317                 _silent = true;
 318                 return;
 319         }
 320
 321         if (events.empty() || next_event == events.end()) {
 322                 process_without_events (nframes);
 323                 return;
 324         }
 325
 326         if (_transport_speed == 1.0) {
 327                 frames_moved = (long) nframes;
 328         } else {
 329                 interpolation.set_target_speed (fabs(_target_transport_speed));
 330                 interpolation.set_speed (fabs(_transport_speed));
 331                 frames_moved = (long) interpolation.interpolate (0, nframes, 0, 0);
 332         }
 333
 334         end_frame = _transport_frame + (nframes_t)frames_moved;
 335
 336         {
 337                 Event* this_event;
 338                 Events::iterator the_next_one;
 339
 340                 if (!process_can_proceed()) {
 341                         _silent = true;
 342                         return;
 343                 }
 344
 345                 if (!_exporting && _slave) {
 346                         if (!follow_slave (nframes)) {
 347                                 return;
 348                         }
 349                 }
 350
 351                 if (_transport_speed == 0) {
 352                         no_roll (nframes);
 353                         return;
 354                 }
 355
 356                 if (!_exporting) {
 357                         send_midi_time_code_for_cycle (nframes);
 358                 }
 359
 360                 if (actively_recording()) {
 361                         stop_limit = max_frames;
 362                 } else {
 363
 364                         if (Config->get_stop_at_session_end()) {
 365                                 stop_limit = current_end_frame();
 366                         } else {
 367                                 stop_limit = max_frames;
 368                         }
 369                 }
 370
 371                 if (maybe_stop (stop_limit)) {
 372                         no_roll (nframes);
 373                         return;
 374                 }
 375
 376                 this_event = *next_event;
 377                 the_next_one = next_event;
 378                 ++the_next_one;
 379
 380                 /* yes folks, here it is, the actual loop where we really truly
 381                    process some audio
 382                 */
 383
 384                 while (nframes) {
 385
 386                         this_nframes = nframes; /* real (jack) time relative */
 387                         frames_moved = (long) floor (_transport_speed * nframes); /* transport relative */
 388
 389                         /* running an event, position transport precisely to its time */
 390                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 391                                 /* this isn't quite right for reverse play */
 392                                 frames_moved = (long) (this_event->action_frame - _transport_frame);
 393                                 this_nframes = (nframes_t) abs( floor(frames_moved / _transport_speed) );
 394                         }
 395
 396                         if (this_nframes) {
 397
 398                                 click (_transport_frame, this_nframes);
 399
 400                                 /* now process frames between now and the first event in this block */
 401                                 prepare_diskstreams ();
 402
 403                                 if (process_routes (this_nframes)) {
 404                                         fail_roll (nframes);
 405                                         return;
 406                                 }
 407
 408                                 commit_diskstreams (this_nframes, session_needs_butler);
 409
 410                                 nframes -= this_nframes;
 411
 412                                 if (frames_moved < 0) {
 413                                         decrement_transport_position (-frames_moved);
 414                                 } else {
 415                                         increment_transport_position (frames_moved);
 416                                 }
 417
 418                                 maybe_stop (stop_limit);
 419                                 check_declick_out ();
 420                         }
 421
 422                         _engine.split_cycle (this_nframes);
 423
 424                         /* now handle this event and all others scheduled for the same time */
 425
 426                         while (this_event && this_event->action_frame == _transport_frame) {
 427                                 process_event (this_event);
 428
 429                                 if (the_next_one == events.end()) {
 430                                         this_event = 0;
 431                                 } else {
 432                                         this_event = *the_next_one;
 433                                         ++the_next_one;
 434                                 }
 435                         }
 436
 437                         /* if an event left our state changing, do the right thing */
 438
 439                         if (nframes && non_realtime_work_pending()) {
 440                                 no_roll (nframes);
 441                                 break;
 442                         }
 443
 444                         /* this is necessary to handle the case of seamless looping */
 445                         end_frame = _transport_frame + (nframes_t) floor (nframes * _transport_speed);
 446
 447                 }
 448
 449                 set_next_event ();
 450
 451         } /* implicit release of route lock */
 452
 453         if (session_needs_butler) {
 454                 _butler->summon ();
 455         }
 456 }
 457
 458 void
 459 Session::reset_slave_state ()
 460 {
 461         average_slave_delta = 1800;
 462         delta_accumulator_cnt = 0;
 463         have_first_delta_accumulator = false;
 464         slave_state = Stopped;
 465 }
 466
 467 bool
 468 Session::transport_locked () const
 469 {
 470         Slave* sl = _slave;
 471
 472         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 473                 return true;
 474         }
 475
 476         return false;
 477 }
 478
 479 bool
 480 Session::follow_slave (nframes_t nframes)
 481 {
 482         double slave_speed;
 483         nframes64_t slave_transport_frame;
 484         nframes_t this_delta;
 485         int dir;
 486         bool starting;
 487
 488         if (!_slave->ok()) {
 489                 stop_transport ();
 490                 config.set_external_sync (false);
 491                 goto noroll;
 492         }
 493
 494         _slave->speed_and_position (slave_speed, slave_transport_frame);
 495
 496         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave @ %2 speed %1\n", slave_speed, slave_transport_frame));
 497
 498         if (!_slave->locked()) {
 499                 goto noroll;
 500         }
 501
 502         if (slave_transport_frame > _transport_frame) {
 503                 this_delta = slave_transport_frame - _transport_frame;
 504                 dir = 1;
 505         } else {
 506                 this_delta = _transport_frame - slave_transport_frame;
 507                 dir = -1;
 508         }
 509
 510         if ((starting = _slave->starting())) {
 511                 slave_speed = 0.0f;
 512         }
 513
 514         if (_slave->is_always_synced() || config.get_timecode_source_is_synced()) {
 515
 516                 /* if the TC source is synced, then we assume that its
 517                    speed is binary: 0.0 or 1.0
 518                 */
 519
 520                 if (slave_speed != 0.0f) {
 521                         slave_speed = 1.0f;
 522                 }
 523
 524         } else {
 525
 526                 /* TC source is able to drift relative to us (slave)
 527                    so we need to keep track of the drift and adjust
 528                    our speed to remain locked.
 529                 */
 530
 531                 calculate_moving_average_of_slave_delta(dir, this_delta);
 532         }
 533
 534         track_slave_state(slave_speed, slave_transport_frame, this_delta, starting);
 535
 536         if (slave_state == Running && !_slave->is_always_synced() && !config.get_timecode_source_is_synced()) {
 537
 538                 if (_transport_speed != 0.0f) {
 539
 540                         /*
 541                            note that average_dir is +1 or -1
 542                         */
 543
 544                         float delta;
 545
 546 #ifdef USE_MOVING_AVERAGE_OF_SLAVE
 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 #else
 555                         delta = this_delta;
 556                         delta *= dir;
 557 #endif
 558
 559                         if (fabs(delta) > frames_per_cycle()) {
 560                                 /* too far off, so locate and keep rolling */
 561                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave delta is too big, locate to %1\n", slave_transport_frame));
 562                                 request_locate (slave_transport_frame, true);
 563                         } else {
 564                                 float adjusted_speed = slave_speed + (delta /  float(_current_frame_rate));
 565
 566                                 if (_slave->give_slave_full_control_over_transport_speed()) {
 567                                         request_transport_speed(slave_speed);
 568                                 } else {
 569                                         request_transport_speed(adjusted_speed);
 570                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 571                                                                                    delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 572                                                                                    slave_speed));
 573                                 }
 574                         }
 575
 576                         if (abs(average_slave_delta) > (long) _slave->resolution()) {
 577                                 cerr << "average slave delta greater than slave resolution, going to silent motion\n";
 578                                 goto silent_motion;
 579                         }
 580                 }
 581         }
 582
 583 #ifndef NDEBUG
 584         if (slave_speed != 0.0) {
 585                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 586                                                            (int) (dir * this_delta),
 587                                                            slave_speed,
 588                                                            _transport_speed,
 589                                                            slave_transport_frame,
 590                                                            _transport_frame,
 591                                                            average_slave_delta));
 592         }
 593 #endif
 594
 595         if (!starting && !non_realtime_work_pending()) {
 596                 /* speed is set, we're locked, and good to go */
 597                 return true;
 598         }
 599
 600   silent_motion:
 601         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 602         follow_slave_silently (nframes, slave_speed);
 603
 604   noroll:
 605         /* don't move at all */
 606         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 607         no_roll (nframes);
 608         return false;
 609 }
 610
 611 void
 612 Session::calculate_moving_average_of_slave_delta(int dir, nframes_t this_delta)
 613 {
 614         if (delta_accumulator_cnt >= delta_accumulator_size) {
 615                 have_first_delta_accumulator = true;
 616                 delta_accumulator_cnt = 0;
 617         }
 618
 619         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 620                 delta_accumulator[delta_accumulator_cnt++] = long(dir) * long(this_delta);
 621         }
 622
 623         if (have_first_delta_accumulator) {
 624                 average_slave_delta = 0L;
 625                 for (int i = 0; i < delta_accumulator_size; ++i) {
 626                         average_slave_delta += delta_accumulator[i];
 627                 }
 628                 average_slave_delta /= long(delta_accumulator_size);
 629                 if (average_slave_delta < 0L) {
 630                         average_dir = -1;
 631                         average_slave_delta = abs(average_slave_delta);
 632                 } else {
 633                         average_dir = 1;
 634                 }
 635         }
 636 }
 637
 638 void
 639 Session::track_slave_state(
 640                 float slave_speed,
 641                 nframes_t slave_transport_frame,
 642                 nframes_t this_delta,
 643                 bool starting)
 644 {
 645         if (slave_speed != 0.0f) {
 646
 647                 /* slave is running */
 648
 649                 switch (slave_state) {
 650                 case Stopped:
 651                         if (_slave->requires_seekahead()) {
 652                                 slave_wait_end = slave_transport_frame + _current_frame_rate;
 653                                 locate (slave_wait_end, false, false);
 654                                 slave_state = Waiting;
 655                                 starting = true;
 656
 657                         } else {
 658
 659                                 slave_state = Running;
 660
 661                                 Location* al = _locations.auto_loop_location();
 662
 663                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 664                                         // cancel looping
 665                                         request_play_loop(false);
 666                                 }
 667
 668                                 if (slave_transport_frame != _transport_frame) {
 669                                         locate (slave_transport_frame, false, false);
 670                                 }
 671                         }
 672                         break;
 673
 674                 case Waiting:
 675                         break;
 676
 677                 default:
 678                         break;
 679
 680                 }
 681
 682                 if (slave_state == Waiting) {
 683
 684                 #ifdef DEBUG_SLAVES
 685                         cerr << "waiting at " << slave_transport_frame << endl;
 686                 #endif
 687                         if (slave_transport_frame >= slave_wait_end) {
 688 #ifdef DEBUG_SLAVES
 689                                 cerr << "\tstart at " << _transport_frame << endl;
 690 #endif
 691                                 slave_state = Running;
 692
 693                                 bool ok = true;
 694                                 nframes_t frame_delta = slave_transport_frame - _transport_frame;
 695
 696                                 boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
 697
 698                                 for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 699                                         if (!(*i)->can_internal_playback_seek (frame_delta)) {
 700                                                 ok = false;
 701                                                 break;
 702                                         }
 703                                 }
 704
 705                                 if (ok) {
 706                                         for (DiskstreamList::iterator i = dsl->begin(); i != dsl->end(); ++i) {
 707                                                 (*i)->internal_playback_seek (frame_delta);
 708                                         }
 709                                         _transport_frame += frame_delta;
 710
 711                                 } else {
 712                                         cerr << "cannot micro-seek\n";
 713                                         /* XXX what? */
 714                                 }
 715
 716                                 memset (delta_accumulator, 0, sizeof (long) * delta_accumulator_size);
 717                                 average_slave_delta = 0L;
 718                                 this_delta = 0;
 719                         }
 720                 }
 721
 722                 if (slave_state == Running && _transport_speed == 0.0f) {
 723                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 724                         start_transport ();
 725                 }
 726
 727         } else { // slave_speed is 0
 728
 729                 /* slave has stopped */
 730
 731                 if (_transport_speed != 0.0f) {
 732                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 733                         stop_transport();
 734                 }
 735
 736                 if (slave_transport_frame != _transport_frame) {
 737                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 738                         force_locate (slave_transport_frame, false);
 739                 }
 740
 741                 slave_state = Stopped;
 742         }
 743 }
 744
 745 void
 746 Session::follow_slave_silently (nframes_t nframes, float slave_speed)
 747 {
 748         if (slave_speed && _transport_speed) {
 749
 750                 /* something isn't right, but we should move with the master
 751                    for now.
 752                 */
 753
 754                 bool need_butler;
 755
 756                 prepare_diskstreams ();
 757                 silent_process_routes (nframes);
 758                 commit_diskstreams (nframes, need_butler);
 759
 760                 if (need_butler) {
 761                         _butler->summon ();
 762                 }
 763
 764                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 765
 766                 if (frames_moved < 0) {
 767                         decrement_transport_position (-frames_moved);
 768                 } else {
 769                         increment_transport_position (frames_moved);
 770                 }
 771
 772                 nframes_t stop_limit;
 773
 774                 if (actively_recording()) {
 775                         stop_limit = max_frames;
 776                 } else {
 777                         if (Config->get_stop_at_session_end()) {
 778                                 stop_limit = current_end_frame();
 779                         } else {
 780                                 stop_limit = max_frames;
 781                         }
 782                 }
 783
 784                 maybe_stop (stop_limit);
 785         }
 786 }
 787
 788 void
 789 Session::process_without_events (nframes_t nframes)
 790 {
 791         bool session_needs_butler = false;
 792         nframes_t stop_limit;
 793         long frames_moved;
 794
 795         if (!process_can_proceed()) {
 796                 _silent = true;
 797                 return;
 798         }
 799
 800         if (!_exporting && _slave) {
 801                 if (!follow_slave (nframes)) {
 802                         return;
 803                 }
 804         }
 805
 806         if (_transport_speed == 0) {
 807                 fail_roll (nframes);
 808                 return;
 809         }
 810
 811         if (!_exporting) {
 812                 send_midi_time_code_for_cycle (nframes);
 813         }
 814
 815         if (actively_recording()) {
 816                 stop_limit = max_frames;
 817         } else {
 818                 if (Config->get_stop_at_session_end()) {
 819                         stop_limit = current_end_frame();
 820                 } else {
 821                         stop_limit = max_frames;
 822                 }
 823         }
 824
 825         if (maybe_stop (stop_limit)) {
 826                 fail_roll (nframes);
 827                 return;
 828         }
 829
 830         if (maybe_sync_start (nframes)) {
 831                 return;
 832         }
 833
 834         click (_transport_frame, nframes);
 835
 836         prepare_diskstreams ();
 837
 838         if (_transport_speed == 1.0) {
 839                 frames_moved = (long) nframes;
 840         } else {
 841                 interpolation.set_target_speed (fabs(_target_transport_speed));
 842                 interpolation.set_speed (fabs(_transport_speed));
 843                 frames_moved = (long) interpolation.interpolate (0, nframes, 0, 0);
 844         }
 845
 846         if (process_routes (nframes)) {
 847                 fail_roll (nframes);
 848                 return;
 849         }
 850
 851         commit_diskstreams (nframes, session_needs_butler);
 852
 853         if (frames_moved < 0) {
 854                 decrement_transport_position (-frames_moved);
 855         } else {
 856                 increment_transport_position (frames_moved);
 857         }
 858
 859         maybe_stop (stop_limit);
 860         check_declick_out ();
 861
 862         if (session_needs_butler) {
 863                 _butler->summon ();
 864         }
 865 }
 866
 867 /** Process callback used when the auditioner is active.
 868  * @param nframes number of frames to process.
 869  */
 870 void
 871 Session::process_audition (nframes_t nframes)
 872 {
 873         Event* ev;
 874         boost::shared_ptr<RouteList> r = routes.reader ();
 875
 876         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 877                 if (!(*i)->is_hidden()) {
 878                         (*i)->silence (nframes);
 879                 }
 880         }
 881
 882         /* run the auditioner, and if it says we need butler service, ask for it */
 883
 884         if (auditioner->play_audition (nframes) > 0) {
 885                 _butler->summon ();
 886         }
 887
 888         /* handle pending events */
 889
 890         while (pending_events.read (&ev, 1) == 1) {
 891                 merge_event (ev);
 892         }
 893
 894         /* if we are not in the middle of a state change,
 895            and there are immediate events queued up,
 896            process them.
 897         */
 898
 899         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 900                 Event *ev = immediate_events.front ();
 901                 immediate_events.pop_front ();
 902                 process_event (ev);
 903         }
 904
 905         if (!auditioner->active()) {
 906                 /* auditioner no longer active, so go back to the normal process callback */
 907                 process_function = &Session::process_with_events;
 908         }
 909 }
 910
 911 bool
 912 Session::maybe_sync_start (nframes_t& nframes)
 913 {
 914         nframes_t sync_offset;
 915
 916         if (!waiting_for_sync_offset) {
 917                 return false;
 918         }
 919
 920         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 921
 922                 /* generate silence up to the sync point, then
 923                    adjust nframes + offset to reflect whatever
 924                    is left to do.
 925                 */
 926
 927                 no_roll (sync_offset);
 928                 nframes -= sync_offset;
 929                 Port::increment_port_offset (sync_offset);
 930                 waiting_for_sync_offset = false;
 931
 932                 if (nframes == 0) {
 933                         return true; // done, nothing left to process
 934                 }
 935
 936         } else {
 937
 938                 /* sync offset point is not within this process()
 939                    cycle, so just generate silence. and don't bother
 940                    with any fancy stuff here, just the minimal silence.
 941                 */
 942
 943                 _silent = true;
 944
 945                 if (Config->get_locate_while_waiting_for_sync()) {
 946                         if (micro_locate (nframes)) {
 947                                 /* XXX ERROR !!! XXX */
 948                         }
 949                 }
 950
 951                 return true; // done, nothing left to process
 952         }
 953
 954         return false;
 955 }
 956