libs/ardour/session_process.cc

   1 /*
   2     Copyright (C) 1999-2002 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <cmath>
  21 #include <cerrno>
  22 #include <algorithm>
  23 #include <unistd.h>
  24
  25 #include "pbd/error.h"
  26 #include "pbd/enumwriter.h"
  27
  28 #include <glibmm/threads.h>
  29
  30 #include "ardour/audioengine.h"
  31 #include "ardour/auditioner.h"
  32 #include "ardour/butler.h"
  33 #include "ardour/cycle_timer.h"
  34 #include "ardour/debug.h"
  35 #include "ardour/graph.h"
  36 #include "ardour/port.h"
  37 #include "ardour/process_thread.h"
  38 #include "ardour/scene_changer.h"
  39 #include "ardour/session.h"
  40 #include "ardour/slave.h"
  41 #include "ardour/ticker.h"
  42 #include "ardour/types.h"
  43
  44 #include "midi++/mmc.h"
  45
  46 #include "pbd/i18n.h"
  47
  48 using namespace ARDOUR;
  49 using namespace PBD;
  50 using namespace std;
  51
  52 /** Called by the audio engine when there is work to be done with JACK.
  53  * @param nframes Number of frames to process.
  54  */
  55
  56 void
  57 Session::process (pframes_t nframes)
  58 {
  59         framepos_t transport_at_start = _transport_frame;
  60
  61         _silent = false;
  62
  63         if (processing_blocked()) {
  64                 _silent = true;
  65                 return;
  66         }
  67
  68         if (non_realtime_work_pending()) {
  69                 if (!_butler->transport_work_requested ()) {
  70                         post_transport ();
  71                 }
  72         }
  73
  74         _engine.main_thread()->get_buffers ();
  75
  76         (this->*process_function) (nframes);
  77
  78         /* realtime-safe meter-position and processor-order changes
  79          *
  80          * ideally this would be done in
  81          * Route::process_output_buffers() but various functions
  82          * callig it hold a _processor_lock reader-lock
  83          */
  84         boost::shared_ptr<RouteList> r = routes.reader ();
  85         for (RouteList::const_iterator i = r->begin(); i != r->end(); ++i) {
  86                 if ((*i)->apply_processor_changes_rt()) {
  87                         _rt_emit_pending = true;
  88                 }
  89         }
  90         if (_rt_emit_pending) {
  91                 if (!_rt_thread_active) {
  92                         emit_route_signals ();
  93                 }
  94                 if (pthread_mutex_trylock (&_rt_emit_mutex) == 0) {
  95                         pthread_cond_signal (&_rt_emit_cond);
  96                         pthread_mutex_unlock (&_rt_emit_mutex);
  97                         _rt_emit_pending = false;
  98                 }
  99         }
 100
 101         _engine.main_thread()->drop_buffers ();
 102
 103         /* deliver MIDI clock. Note that we need to use the transport frame
 104          * position at the start of process(), not the value at the end of
 105          * it. We may already have ticked() because of a transport state
 106          * change, for example.
 107          */
 108
 109         try {
 110                 if (!_silent && !_engine.freewheeling() && Config->get_send_midi_clock() && (transport_speed() == 1.0f || transport_speed() == 0.0f) && midi_clock->has_midi_port()) {
 111                         midi_clock->tick (transport_at_start, nframes);
 112                 }
 113
 114                 _scene_changer->run (transport_at_start, transport_at_start + nframes);
 115
 116         } catch (...) {
 117                 /* don't bother with a message */
 118         }
 119
 120         SendFeedback (); /* EMIT SIGNAL */
 121 }
 122
 123 int
 124 Session::fail_roll (pframes_t nframes)
 125 {
 126         return no_roll (nframes);
 127 }
 128
 129 int
 130 Session::no_roll (pframes_t nframes)
 131 {
 132         PT_TIMING_CHECK (4);
 133
 134         framepos_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 135         int ret = 0;
 136         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 137         boost::shared_ptr<RouteList> r = routes.reader ();
 138
 139         if (_click_io) {
 140                 _click_io->silence (nframes);
 141         }
 142
 143         ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 144
 145         if (_process_graph) {
 146                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 147                 _process_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), declick);
 148         } else {
 149                 PT_TIMING_CHECK (10);
 150                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 151
 152                         if ((*i)->is_auditioner()) {
 153                                 continue;
 154                         }
 155
 156                         (*i)->set_pending_declick (declick);
 157
 158                         if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending())) {
 159                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 160                                 ret = -1;
 161                                 break;
 162                         }
 163                 }
 164                 PT_TIMING_CHECK (11);
 165         }
 166
 167         PT_TIMING_CHECK (5);
 168         return ret;
 169 }
 170
 171 /** @param need_butler to be set to true by this method if it needs the butler,
 172  *  otherwise it must be left alone.
 173  */
 174 int
 175 Session::process_routes (pframes_t nframes, bool& need_butler)
 176 {
 177         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 178         boost::shared_ptr<RouteList> r = routes.reader ();
 179
 180         const framepos_t start_frame = _transport_frame;
 181         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 182
 183         if (_process_graph) {
 184                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 185                 if (_process_graph->process_routes (nframes, start_frame, end_frame, declick, need_butler) < 0) {
 186                         stop_transport ();
 187                         return -1;
 188                 }
 189         } else {
 190
 191                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 192
 193                         int ret;
 194
 195                         if ((*i)->is_auditioner()) {
 196                                 continue;
 197                         }
 198
 199                         (*i)->set_pending_declick (declick);
 200
 201                         bool b = false;
 202
 203                         if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, b)) < 0) {
 204                                 stop_transport ();
 205                                 return -1;
 206                         }
 207
 208                         if (b) {
 209                                 need_butler = true;
 210                         }
 211                 }
 212         }
 213
 214         return 0;
 215 }
 216
 217 /** @param need_butler to be set to true by this method if it needs the butler,
 218  *  otherwise it must be left alone.
 219  */
 220 int
 221 Session::silent_process_routes (pframes_t nframes, bool& need_butler)
 222 {
 223         boost::shared_ptr<RouteList> r = routes.reader ();
 224
 225         const framepos_t start_frame = _transport_frame;
 226         const framepos_t end_frame = _transport_frame + lrintf(nframes * _transport_speed);
 227
 228         if (_process_graph) {
 229                 _process_graph->silent_process_routes (nframes, start_frame, end_frame, need_butler);
 230         } else {
 231                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 232
 233                         int ret;
 234
 235                         if ((*i)->is_auditioner()) {
 236                                 continue;
 237                         }
 238
 239                         bool b = false;
 240
 241                         if ((ret = (*i)->silent_roll (nframes, start_frame, end_frame, b)) < 0) {
 242                                 stop_transport ();
 243                                 return -1;
 244                         }
 245
 246                         if (b) {
 247                                 need_butler = true;
 248                         }
 249                 }
 250         }
 251
 252         return 0;
 253 }
 254
 255 void
 256 Session::get_track_statistics ()
 257 {
 258         float pworst = 1.0f;
 259         float cworst = 1.0f;
 260
 261         boost::shared_ptr<RouteList> rl = routes.reader();
 262         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 263
 264                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 265
 266                 if (!tr || tr->hidden()) {
 267                         continue;
 268                 }
 269
 270                 pworst = min (pworst, tr->playback_buffer_load());
 271                 cworst = min (cworst, tr->capture_buffer_load());
 272         }
 273
 274         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 275         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 276
 277         if (actively_recording()) {
 278                 set_dirty();
 279         }
 280 }
 281
 282 /** Process callback used when the auditioner is not active */
 283 void
 284 Session::process_with_events (pframes_t nframes)
 285 {
 286         PT_TIMING_CHECK (3);
 287
 288         SessionEvent*  ev;
 289         pframes_t      this_nframes;
 290         framepos_t     end_frame;
 291         bool           session_needs_butler = false;
 292         framecnt_t     frames_moved;
 293
 294         /* make sure the auditioner is silent */
 295
 296         if (auditioner) {
 297                 auditioner->silence (nframes);
 298         }
 299
 300         /* handle any pending events */
 301
 302         while (pending_events.read (&ev, 1) == 1) {
 303                 merge_event (ev);
 304         }
 305
 306         /* if we are not in the middle of a state change,
 307            and there are immediate events queued up,
 308            process them.
 309         */
 310
 311         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 312                 SessionEvent *ev = immediate_events.front ();
 313                 immediate_events.pop_front ();
 314                 process_event (ev);
 315         }
 316
 317         /* Decide on what to do with quarter-frame MTC during this cycle */
 318
 319         bool const was_sending_qf_mtc = _send_qf_mtc;
 320         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 321
 322         if (_transport_speed != 0) {
 323                 _send_qf_mtc = (
 324                         Config->get_send_mtc () &&
 325                         _transport_speed >= (1 - tolerance) &&
 326                         _transport_speed <= (1 + tolerance)
 327                         );
 328
 329                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 330                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 331                         _send_timecode_update = true;
 332                 }
 333
 334                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (frame_rate () / 4)) {
 335                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 336                            a quarter of a second since we sent anything at all, so send a full MTC update
 337                            this cycle.
 338                         */
 339                         _send_timecode_update = true;
 340                 }
 341
 342                 _pframes_since_last_mtc += nframes;
 343         }
 344
 345         /* Events caused a transport change (or we re-started sending
 346          * MTC), so send an MTC Full Frame (Timecode) message.  This
 347          * is sent whether rolling or not, to give slaves an idea of
 348          * ardour time on locates (and allow slow slaves to position
 349          * and prepare for rolling)
 350          */
 351         if (_send_timecode_update) {
 352                 send_full_time_code (_transport_frame, nframes);
 353         }
 354
 355         if (!process_can_proceed()) {
 356                 _silent = true;
 357                 return;
 358         }
 359
 360         if (events.empty() || next_event == events.end()) {
 361                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 362                 /* lua scripts may inject events */
 363                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 364                         merge_event (ev);
 365                 }
 366                 if (events.empty() || next_event == events.end()) {
 367                         process_without_events (nframes);
 368                         return;
 369                 }
 370         }
 371
 372         if (_transport_speed == 1.0) {
 373                 frames_moved = (framecnt_t) nframes;
 374         } else {
 375                 interpolation.set_target_speed (_target_transport_speed);
 376                 interpolation.set_speed (_transport_speed);
 377                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 378         }
 379
 380         end_frame = _transport_frame + frames_moved;
 381
 382         {
 383                 SessionEvent* this_event;
 384                 Events::iterator the_next_one;
 385
 386                 if (!process_can_proceed()) {
 387                         _silent = true;
 388                         return;
 389                 }
 390
 391                 if (!_exporting && _slave) {
 392                         if (!follow_slave (nframes)) {
 393                                 return;
 394                         }
 395                 }
 396
 397                 if (_transport_speed == 0) {
 398                         no_roll (nframes);
 399                         return;
 400                 }
 401
 402                 if (!_exporting && !timecode_transmission_suspended()) {
 403                         send_midi_time_code_for_cycle (_transport_frame, end_frame, nframes);
 404                 }
 405
 406                 ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 407
 408                 framepos_t stop_limit = compute_stop_limit ();
 409
 410                 if (maybe_stop (stop_limit)) {
 411                         no_roll (nframes);
 412                         return;
 413                 }
 414
 415                 this_event = *next_event;
 416                 the_next_one = next_event;
 417                 ++the_next_one;
 418
 419                 /* yes folks, here it is, the actual loop where we really truly
 420                    process some audio
 421                 */
 422
 423                 while (nframes) {
 424
 425                         this_nframes = nframes; /* real (jack) time relative */
 426                         frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 427
 428                         /* running an event, position transport precisely to its time */
 429                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 430                                 /* this isn't quite right for reverse play */
 431                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 432                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 433                         }
 434
 435                         try_run_lua (this_nframes);
 436
 437                         if (this_nframes) {
 438
 439                                 click (_transport_frame, this_nframes);
 440
 441                                 if (process_routes (this_nframes, session_needs_butler)) {
 442                                         fail_roll (nframes);
 443                                         return;
 444                                 }
 445
 446                                 get_track_statistics ();
 447
 448                                 nframes -= this_nframes;
 449
 450                                 if (frames_moved < 0) {
 451                                         decrement_transport_position (-frames_moved);
 452                                 } else {
 453                                         increment_transport_position (frames_moved);
 454                                 }
 455
 456                                 maybe_stop (stop_limit);
 457                                 check_declick_out ();
 458                         }
 459
 460                         if (nframes > 0) {
 461                                 _engine.split_cycle (this_nframes);
 462                         }
 463
 464                         /* now handle this event and all others scheduled for the same time */
 465
 466                         while (this_event && this_event->action_frame == _transport_frame) {
 467                                 process_event (this_event);
 468
 469                                 if (the_next_one == events.end()) {
 470                                         this_event = 0;
 471                                 } else {
 472                                         this_event = *the_next_one;
 473                                         ++the_next_one;
 474                                 }
 475                         }
 476
 477                         /* if an event left our state changing, do the right thing */
 478
 479                         if (nframes && non_realtime_work_pending()) {
 480                                 no_roll (nframes);
 481                                 break;
 482                         }
 483
 484                         /* this is necessary to handle the case of seamless looping */
 485                         end_frame = _transport_frame + floor (nframes * _transport_speed);
 486                 }
 487
 488                 set_next_event ();
 489
 490         } /* implicit release of route lock */
 491
 492         if (session_needs_butler) {
 493                 _butler->summon ();
 494         }
 495 }
 496
 497 void
 498 Session::reset_slave_state ()
 499 {
 500         average_slave_delta = 1800;
 501         delta_accumulator_cnt = 0;
 502         have_first_delta_accumulator = false;
 503         _slave_state = Stopped;
 504 }
 505
 506 bool
 507 Session::transport_locked () const
 508 {
 509         Slave* sl = _slave;
 510
 511         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 512                 return true;
 513         }
 514
 515         return false;
 516 }
 517
 518 bool
 519 Session::follow_slave (pframes_t nframes)
 520 {
 521         double slave_speed;
 522         framepos_t slave_transport_frame;
 523         framecnt_t this_delta;
 524         int dir;
 525
 526         if (!_slave->ok()) {
 527                 stop_transport ();
 528                 config.set_external_sync (false);
 529                 goto noroll;
 530         }
 531
 532         _slave->speed_and_position (slave_speed, slave_transport_frame);
 533
 534         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 535
 536         if (!_slave->locked()) {
 537                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 538                 goto noroll;
 539         }
 540
 541         if (slave_transport_frame > _transport_frame) {
 542                 this_delta = slave_transport_frame - _transport_frame;
 543                 dir = 1;
 544         } else {
 545                 this_delta = _transport_frame - slave_transport_frame;
 546                 dir = -1;
 547         }
 548
 549         if (_slave->starting()) {
 550                 slave_speed = 0.0f;
 551         }
 552
 553         if (_slave->is_always_synced() ||
 554                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 555                         ) {
 556
 557                 /* if the TC source is synced, then we assume that its
 558                    speed is binary: 0.0 or 1.0
 559                 */
 560
 561                 if (slave_speed != 0.0f) {
 562                         slave_speed = 1.0f;
 563                 }
 564
 565         } else {
 566
 567                 /* if we are chasing and the average delta between us and the
 568                    master gets too big, we want to switch to silent
 569                    motion. so keep track of that here.
 570                 */
 571
 572                 if (_slave_state == Running) {
 573                         calculate_moving_average_of_slave_delta(dir, this_delta);
 574                 }
 575         }
 576
 577         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 578
 579         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 580                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 581
 582
 583         if (_slave_state == Running && !_slave->is_always_synced() &&
 584                         !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 585                         ) {
 586
 587                 if (_transport_speed != 0.0f) {
 588
 589                         /*
 590                            note that average_dir is +1 or -1
 591                         */
 592
 593                         float delta;
 594
 595                         if (average_slave_delta == 0) {
 596                                 delta = this_delta;
 597                                 delta *= dir;
 598                         } else {
 599                                 delta = average_slave_delta;
 600                                 delta *= average_dir;
 601                         }
 602
 603 #ifndef NDEBUG
 604                         if (slave_speed != 0.0) {
 605                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 606                                                                            (int) (dir * this_delta),
 607                                                                            slave_speed,
 608                                                                            _transport_speed,
 609                                                                            _transport_frame,
 610                                                                            slave_transport_frame,
 611                                                                            average_slave_delta));
 612                         }
 613 #endif
 614
 615                         if (_slave->give_slave_full_control_over_transport_speed()) {
 616                                 set_transport_speed (slave_speed, 0, false, false);
 617                                 //std::cout << "set speed = " << slave_speed << "\n";
 618                         } else {
 619                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 620                                 request_transport_speed (adjusted_speed);
 621                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 622                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 623                                                                            slave_speed));
 624                         }
 625
 626 #if 1
 627                         if (!actively_recording() && (framecnt_t) abs(average_slave_delta) > _slave->resolution()) {
 628                                 cerr << "average slave delta greater than slave resolution (" << _slave->resolution() << "), going to silent motion\n";
 629                                 goto silent_motion;
 630                         }
 631 #endif
 632                 }
 633         }
 634
 635
 636         if (_slave_state == Running && !non_realtime_work_pending()) {
 637                 /* speed is set, we're locked, and good to go */
 638                 return true;
 639         }
 640
 641   silent_motion:
 642         DEBUG_TRACE (DEBUG::Slave, "silent motion\n")
 643         follow_slave_silently (nframes, slave_speed);
 644
 645   noroll:
 646         /* don't move at all */
 647         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 648         no_roll (nframes);
 649         return false;
 650 }
 651
 652 void
 653 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 654 {
 655         if (delta_accumulator_cnt >= delta_accumulator_size) {
 656                 have_first_delta_accumulator = true;
 657                 delta_accumulator_cnt = 0;
 658         }
 659
 660         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 661                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 662         }
 663
 664         if (have_first_delta_accumulator) {
 665                 average_slave_delta = 0L;
 666                 for (int i = 0; i < delta_accumulator_size; ++i) {
 667                         average_slave_delta += delta_accumulator[i];
 668                 }
 669                 average_slave_delta /= (int32_t) delta_accumulator_size;
 670                 if (average_slave_delta < 0L) {
 671                         average_dir = -1;
 672                         average_slave_delta = abs(average_slave_delta);
 673                 } else {
 674                         average_dir = 1;
 675                 }
 676         }
 677 }
 678
 679 void
 680 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t /*this_delta*/)
 681 {
 682         if (slave_speed != 0.0f) {
 683
 684                 /* slave is running */
 685
 686                 switch (_slave_state) {
 687                 case Stopped:
 688                         if (_slave->requires_seekahead()) {
 689                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 690                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 691                                 /* we can call locate() here because we are in process context */
 692                                 locate (slave_wait_end, false, false);
 693                                 _slave_state = Waiting;
 694
 695                         } else {
 696
 697                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_frame));
 698
 699                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 700                                 average_slave_delta = 0L;
 701
 702                                 Location* al = _locations->auto_loop_location();
 703
 704                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 705                                         // cancel looping
 706                                         request_play_loop(false);
 707                                 }
 708
 709                                 if (slave_transport_frame != _transport_frame) {
 710                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_frame, slave_transport_frame));
 711                                         locate (slave_transport_frame, false, false);
 712                                 }
 713                                 _slave_state = Running;
 714                         }
 715                         break;
 716
 717                 case Waiting:
 718                 default:
 719                         break;
 720                 }
 721
 722                 if (_slave_state == Waiting) {
 723
 724                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 725
 726                         if (slave_transport_frame >= slave_wait_end) {
 727
 728                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 729
 730                                 _slave_state = Running;
 731
 732                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 733                                    precisely with the master.
 734                                 */
 735
 736
 737                                 bool ok = true;
 738                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 739
 740                                 boost::shared_ptr<RouteList> rl = routes.reader();
 741                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 742                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 743                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 744                                                 ok = false;
 745                                                 break;
 746                                         }
 747                                 }
 748
 749                                 if (ok) {
 750                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 751                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 752                                                 if (tr) {
 753                                                         tr->internal_playback_seek (frame_delta);
 754                                                 }
 755                                         }
 756                                         _transport_frame += frame_delta;
 757
 758                                 } else {
 759                                         cerr << "cannot micro-seek\n";
 760                                         /* XXX what? */
 761                                 }
 762                         }
 763                 }
 764
 765                 if (_slave_state == Running && _transport_speed == 0.0f) {
 766                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 767                         start_transport ();
 768                 }
 769
 770         } else { // slave_speed is 0
 771
 772                 /* slave has stopped */
 773
 774                 if (_transport_speed != 0.0f) {
 775                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 776                         stop_transport ();
 777                 }
 778
 779                 if (slave_transport_frame != _transport_frame) {
 780                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 781                         force_locate (slave_transport_frame, false);
 782                 }
 783
 784                 reset_slave_state();
 785         }
 786 }
 787
 788 void
 789 Session::follow_slave_silently (pframes_t nframes, float slave_speed)
 790 {
 791         if (slave_speed && _transport_speed) {
 792
 793                 /* something isn't right, but we should move with the master
 794                    for now.
 795                 */
 796
 797                 bool need_butler = false;
 798
 799                 silent_process_routes (nframes, need_butler);
 800
 801                 get_track_statistics ();
 802
 803                 if (need_butler) {
 804                         _butler->summon ();
 805                 }
 806
 807                 int32_t frames_moved = (int32_t) floor (_transport_speed * nframes);
 808
 809                 if (frames_moved < 0) {
 810                         decrement_transport_position (-frames_moved);
 811                 } else {
 812                         increment_transport_position (frames_moved);
 813                 }
 814
 815                 framepos_t const stop_limit = compute_stop_limit ();
 816                 maybe_stop (stop_limit);
 817         }
 818 }
 819
 820 void
 821 Session::process_without_events (pframes_t nframes)
 822 {
 823         bool session_needs_butler = false;
 824         framecnt_t frames_moved;
 825
 826         if (!process_can_proceed()) {
 827                 _silent = true;
 828                 return;
 829         }
 830
 831         if (!_exporting && _slave) {
 832                 if (!follow_slave (nframes)) {
 833                         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame, 0, 0 , nframes);
 834                         return;
 835                 }
 836         }
 837
 838         if (_transport_speed == 0) {
 839                 fail_roll (nframes);
 840                 return;
 841         }
 842
 843         if (_transport_speed == 1.0) {
 844                 frames_moved = (framecnt_t) nframes;
 845         } else {
 846                 interpolation.set_target_speed (_target_transport_speed);
 847                 interpolation.set_speed (_transport_speed);
 848                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 849         }
 850
 851         if (!_exporting && !timecode_transmission_suspended()) {
 852                 send_midi_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, nframes);
 853         }
 854
 855         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, _target_transport_speed, _transport_speed, nframes);
 856
 857         framepos_t const stop_limit = compute_stop_limit ();
 858
 859         if (maybe_stop (stop_limit)) {
 860                 fail_roll (nframes);
 861                 return;
 862         }
 863
 864         if (maybe_sync_start (nframes)) {
 865                 return;
 866         }
 867
 868         click (_transport_frame, nframes);
 869
 870         if (process_routes (nframes, session_needs_butler)) {
 871                 fail_roll (nframes);
 872                 return;
 873         }
 874
 875         get_track_statistics ();
 876
 877         if (frames_moved < 0) {
 878                 decrement_transport_position (-frames_moved);
 879         } else {
 880                 increment_transport_position (frames_moved);
 881         }
 882
 883         maybe_stop (stop_limit);
 884         check_declick_out ();
 885
 886         if (session_needs_butler) {
 887                 _butler->summon ();
 888         }
 889 }
 890
 891 /** Process callback used when the auditioner is active.
 892  * @param nframes number of frames to process.
 893  */
 894 void
 895 Session::process_audition (pframes_t nframes)
 896 {
 897         SessionEvent* ev;
 898         boost::shared_ptr<RouteList> r = routes.reader ();
 899
 900         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 901                 if (!(*i)->is_auditioner()) {
 902                         (*i)->silence (nframes);
 903                 }
 904         }
 905
 906         /* run the auditioner, and if it says we need butler service, ask for it */
 907
 908         if (auditioner->play_audition (nframes) > 0) {
 909                 _butler->summon ();
 910         }
 911
 912         /* if using a monitor section, run it because otherwise we don't hear anything */
 913
 914         if (_monitor_out && auditioner->needs_monitor()) {
 915                 _monitor_out->monitor_run (_transport_frame, _transport_frame + nframes, nframes, false);
 916         }
 917
 918         /* handle pending events */
 919
 920         while (pending_events.read (&ev, 1) == 1) {
 921                 merge_event (ev);
 922         }
 923
 924         /* if we are not in the middle of a state change,
 925            and there are immediate events queued up,
 926            process them.
 927         */
 928
 929         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 930                 SessionEvent *ev = immediate_events.front ();
 931                 immediate_events.pop_front ();
 932                 process_event (ev);
 933         }
 934
 935         if (!auditioner->auditioning()) {
 936                 /* auditioner no longer active, so go back to the normal process callback */
 937                 process_function = &Session::process_with_events;
 938         }
 939 }
 940
 941 bool
 942 Session::maybe_sync_start (pframes_t & nframes)
 943 {
 944         pframes_t sync_offset;
 945
 946         if (!waiting_for_sync_offset) {
 947                 return false;
 948         }
 949
 950         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 951
 952                 /* generate silence up to the sync point, then
 953                    adjust nframes + offset to reflect whatever
 954                    is left to do.
 955                 */
 956
 957                 no_roll (sync_offset);
 958                 nframes -= sync_offset;
 959                 Port::increment_global_port_buffer_offset (sync_offset);
 960                 waiting_for_sync_offset = false;
 961
 962                 if (nframes == 0) {
 963                         return true; // done, nothing left to process
 964                 }
 965
 966         } else {
 967
 968                 /* sync offset point is not within this process()
 969                    cycle, so just generate silence. and don't bother
 970                    with any fancy stuff here, just the minimal silence.
 971                 */
 972
 973                 _silent = true;
 974
 975                 if (Config->get_locate_while_waiting_for_sync()) {
 976                         if (micro_locate (nframes)) {
 977                                 /* XXX ERROR !!! XXX */
 978                         }
 979                 }
 980
 981                 return true; // done, nothing left to process
 982         }
 983
 984         return false;
 985 }
 986
 987 void
 988 Session::queue_event (SessionEvent* ev)
 989 {
 990         if (_state_of_the_state & Deletion) {
 991                 return;
 992         } else if (_state_of_the_state & Loading) {
 993                 merge_event (ev);
 994         } else {
 995                 pending_events.write (&ev, 1);
 996         }
 997 }
 998
 999 void
1000 Session::set_next_event ()
1001 {
1002         if (events.empty()) {
1003                 next_event = events.end();
1004                 return;
1005         }
1006
1007         if (next_event == events.end()) {
1008                 next_event = events.begin();
1009         }
1010
1011         if ((*next_event)->action_frame > _transport_frame) {
1012                 next_event = events.begin();
1013         }
1014
1015         for (; next_event != events.end(); ++next_event) {
1016                 if ((*next_event)->action_frame >= _transport_frame) {
1017                         break;
1018                 }
1019         }
1020 }
1021
1022 void
1023 Session::process_event (SessionEvent* ev)
1024 {
1025         bool remove = true;
1026         bool del = true;
1027
1028         /* if we're in the middle of a state change (i.e. waiting
1029            for the butler thread to complete the non-realtime
1030            part of the change), we'll just have to queue this
1031            event for a time when the change is complete.
1032         */
1033
1034         if (non_realtime_work_pending()) {
1035
1036                 /* except locates, which we have the capability to handle */
1037
1038                 if (ev->type != SessionEvent::Locate) {
1039                         immediate_events.insert (immediate_events.end(), ev);
1040                         _remove_event (ev);
1041                         return;
1042                 }
1043         }
1044
1045         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1046
1047         switch (ev->type) {
1048         case SessionEvent::SetLoop:
1049                 set_play_loop (ev->yes_or_no, ev->speed);
1050                 break;
1051
1052         case SessionEvent::AutoLoop:
1053                 if (play_loop) {
1054                         /* roll after locate, do not flush, set "with loop"
1055                            true only if we are seamless looping
1056                         */
1057                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1058                 }
1059                 remove = false;
1060                 del = false;
1061                 break;
1062
1063         case SessionEvent::AutoLoopDeclick:
1064                 if (play_loop) {
1065                         /* Request a declick fade-out and a fade-in; the fade-out will happen
1066                            at the end of the loop, and the fade-in at the start.
1067                         */
1068                         transport_sub_state |= (PendingLoopDeclickOut | PendingLoopDeclickIn);
1069                 }
1070                 remove = false;
1071                 del = false;
1072                 break;
1073
1074         case SessionEvent::Locate:
1075                 if (ev->yes_or_no) {
1076                         /* args: do not roll after locate, do flush, not with loop */
1077                         locate (ev->target_frame, false, true, false);
1078                 } else {
1079                         /* args: do not roll after locate, do flush, not with loop */
1080                         start_locate (ev->target_frame, false, true, false);
1081                 }
1082                 _send_timecode_update = true;
1083                 break;
1084
1085         case SessionEvent::LocateRoll:
1086                 if (ev->yes_or_no) {
1087                         /* args: roll after locate, do flush, not with loop */
1088                         locate (ev->target_frame, true, true, false);
1089                 } else {
1090                         /* args: roll after locate, do flush, not with loop */
1091                         start_locate (ev->target_frame, true, true, false);
1092                 }
1093                 _send_timecode_update = true;
1094                 break;
1095
1096         case SessionEvent::Skip:
1097                 if (Config->get_skip_playback()) {
1098                         start_locate (ev->target_frame, true, true, false);
1099                         _send_timecode_update = true;
1100                 }
1101                 remove = false;
1102                 del = false;
1103                 break;
1104
1105         case SessionEvent::LocateRollLocate:
1106                 // locate is handled by ::request_roll_at_and_return()
1107                 _requested_return_frame = ev->target_frame;
1108                 request_locate (ev->target2_frame, true);
1109                 break;
1110
1111
1112         case SessionEvent::SetTransportSpeed:
1113                 set_transport_speed (ev->speed, ev->target_frame, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1114                 break;
1115
1116         case SessionEvent::PunchIn:
1117                 // cerr << "PunchIN at " << transport_frame() << endl;
1118                 if (config.get_punch_in() && record_status() == Enabled) {
1119                         enable_record ();
1120                 }
1121                 remove = false;
1122                 del = false;
1123                 break;
1124
1125         case SessionEvent::PunchOut:
1126                 // cerr << "PunchOUT at " << transport_frame() << endl;
1127                 if (config.get_punch_out()) {
1128                         step_back_from_record ();
1129                 }
1130                 remove = false;
1131                 del = false;
1132                 break;
1133
1134         case SessionEvent::StopOnce:
1135                 if (!non_realtime_work_pending()) {
1136                         _clear_event_type (SessionEvent::StopOnce);
1137                         stop_transport (ev->yes_or_no);
1138                 }
1139                 remove = false;
1140                 del = false;
1141                 break;
1142
1143         case SessionEvent::RangeStop:
1144                 if (!non_realtime_work_pending()) {
1145                         stop_transport (ev->yes_or_no);
1146                 }
1147                 remove = false;
1148                 del = false;
1149                 break;
1150
1151         case SessionEvent::RangeLocate:
1152                 /* args: roll after locate, do flush, not with loop */
1153                 start_locate (ev->target_frame, true, true, false);
1154                 remove = false;
1155                 del = false;
1156                 break;
1157
1158         case SessionEvent::Overwrite:
1159                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1160                 break;
1161
1162         case SessionEvent::SetTrackSpeed:
1163                 set_track_speed (static_cast<Track*> (ev->ptr), ev->speed);
1164                 break;
1165
1166         case SessionEvent::SetSyncSource:
1167                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1168                 use_sync_source (ev->slave);
1169                 break;
1170
1171         case SessionEvent::Audition:
1172                 set_audition (ev->region);
1173                 // drop reference to region
1174                 ev->region.reset ();
1175                 break;
1176
1177         case SessionEvent::InputConfigurationChange:
1178                 add_post_transport_work (PostTransportInputChange);
1179                 _butler->schedule_transport_work ();
1180                 break;
1181
1182         case SessionEvent::SetPlayAudioRange:
1183                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1184                 break;
1185
1186         case SessionEvent::CancelPlayAudioRange:
1187                 unset_play_range();
1188                 break;
1189
1190         case SessionEvent::RealTimeOperation:
1191                 process_rtop (ev);
1192                 del = false; // other side of RT request needs to clean up
1193                 break;
1194
1195         case SessionEvent::AdjustPlaybackBuffering:
1196                 schedule_playback_buffering_adjustment ();
1197                 break;
1198
1199         case SessionEvent::AdjustCaptureBuffering:
1200                 schedule_capture_buffering_adjustment ();
1201                 break;
1202
1203         case SessionEvent::SetTimecodeTransmission:
1204                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1205                 break;
1206
1207         default:
1208           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1209                 abort(); /*NOTREACHED*/
1210                 break;
1211         };
1212
1213         if (remove) {
1214                 del = del && !_remove_event (ev);
1215         }
1216
1217         if (del) {
1218                 delete ev;
1219         }
1220 }
1221
1222 framepos_t
1223 Session::compute_stop_limit () const
1224 {
1225         if (!Config->get_stop_at_session_end ()) {
1226                 return max_framepos;
1227         }
1228
1229         if (_slave) {
1230                 return max_framepos;
1231         }
1232
1233
1234         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1235         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1236
1237         if (actively_recording ()) {
1238                 /* permanently recording */
1239                 return max_framepos;
1240         } else if (punching_in && !punching_out) {
1241                 /* punching in but never out */
1242                 return max_framepos;
1243         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_frame()) {
1244                 /* punching in and punching out after session end */
1245                 return max_framepos;
1246         }
1247
1248         return current_end_frame ();
1249 }
1250
1251
1252
1253 /* dedicated thread for signal emission.
1254  *
1255  * while sending cross-thread signals from the process thread
1256  * is fine in general, PBD::Signal's use of boost::function and
1257  * boost:bind can produce a vast overhead which is not
1258  * acceptable for low latency.
1259  *
1260  * This works around the issue by moving the boost overhead
1261  * out of the RT thread. The overall load is probably higher but
1262  * the realtime thread remains unaffected.
1263  */
1264
1265 void
1266 Session::emit_route_signals ()
1267 {
1268         // TODO use RAII to allow using these signals in other places
1269         BatchUpdateStart(); /* EMIT SIGNAL */
1270         boost::shared_ptr<RouteList> r = routes.reader ();
1271         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1272                 (*ci)->emit_pending_signals ();
1273         }
1274         BatchUpdateEnd(); /* EMIT SIGNAL */
1275 }
1276
1277 void
1278 Session::emit_thread_start ()
1279 {
1280         if (_rt_thread_active) {
1281                 return;
1282         }
1283         _rt_thread_active = true;
1284
1285         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1286                 _rt_thread_active = false;
1287         }
1288 }
1289
1290 void
1291 Session::emit_thread_terminate ()
1292 {
1293         if (!_rt_thread_active) {
1294                 return;
1295         }
1296         _rt_thread_active = false;
1297
1298         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1299                 pthread_cond_signal (&_rt_emit_cond);
1300                 pthread_mutex_unlock (&_rt_emit_mutex);
1301         }
1302
1303         void *status;
1304         pthread_join (_rt_emit_thread, &status);
1305 }
1306
1307 void *
1308 Session::emit_thread (void *arg)
1309 {
1310         Session *s = static_cast<Session *>(arg);
1311         s->emit_thread_run ();
1312         pthread_exit (0);
1313         return 0;
1314 }
1315
1316 void
1317 Session::emit_thread_run ()
1318 {
1319         pthread_mutex_lock (&_rt_emit_mutex);
1320         while (_rt_thread_active) {
1321                 emit_route_signals();
1322                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1323         }
1324         pthread_mutex_unlock (&_rt_emit_mutex);
1325 }