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/disk_reader.h"
  36 #include "ardour/graph.h"
  37 #include "ardour/port.h"
  38 #include "ardour/process_thread.h"
  39 #include "ardour/scene_changer.h"
  40 #include "ardour/session.h"
  41 #include "ardour/slave.h"
  42 #include "ardour/ticker.h"
  43 #include "ardour/types.h"
  44 #include "ardour/vca.h"
  45 #include "ardour/vca_manager.h"
  46
  47 #include "midi++/mmc.h"
  48
  49 #include "pbd/i18n.h"
  50
  51 using namespace ARDOUR;
  52 using namespace PBD;
  53 using namespace std;
  54
  55 /** Called by the audio engine when there is work to be done with JACK.
  56  * @param nframes Number of frames to process.
  57  */
  58
  59 void
  60 Session::process (pframes_t nframes)
  61 {
  62         framepos_t transport_at_start = _transport_frame;
  63
  64         _silent = false;
  65
  66         if (processing_blocked()) {
  67                 _silent = true;
  68                 return;
  69         }
  70
  71         if (non_realtime_work_pending()) {
  72                 if (!_butler->transport_work_requested ()) {
  73                         post_transport ();
  74                 }
  75         }
  76
  77         _engine.main_thread()->get_buffers ();
  78
  79         (this->*process_function) (nframes);
  80
  81         /* realtime-safe meter-position and processor-order changes
  82          *
  83          * ideally this would be done in
  84          * Route::process_output_buffers() but various functions
  85          * callig it hold a _processor_lock reader-lock
  86          */
  87         boost::shared_ptr<RouteList> r = routes.reader ();
  88         for (RouteList::const_iterator i = r->begin(); i != r->end(); ++i) {
  89                 if ((*i)->apply_processor_changes_rt()) {
  90                         _rt_emit_pending = true;
  91                 }
  92         }
  93         if (_rt_emit_pending) {
  94                 if (!_rt_thread_active) {
  95                         emit_route_signals ();
  96                 }
  97                 if (pthread_mutex_trylock (&_rt_emit_mutex) == 0) {
  98                         pthread_cond_signal (&_rt_emit_cond);
  99                         pthread_mutex_unlock (&_rt_emit_mutex);
 100                         _rt_emit_pending = false;
 101                 }
 102         }
 103
 104         _engine.main_thread()->drop_buffers ();
 105
 106         /* deliver MIDI clock. Note that we need to use the transport frame
 107          * position at the start of process(), not the value at the end of
 108          * it. We may already have ticked() because of a transport state
 109          * change, for example.
 110          */
 111
 112         try {
 113                 if (!_silent && !_engine.freewheeling() && Config->get_send_midi_clock() && (transport_speed() == 1.0f || transport_speed() == 0.0f) && midi_clock->has_midi_port()) {
 114                         midi_clock->tick (transport_at_start, nframes);
 115                 }
 116
 117                 _scene_changer->run (transport_at_start, transport_at_start + nframes);
 118
 119         } catch (...) {
 120                 /* don't bother with a message */
 121         }
 122
 123         SendFeedback (); /* EMIT SIGNAL */
 124 }
 125
 126 int
 127 Session::fail_roll (pframes_t nframes)
 128 {
 129         return no_roll (nframes);
 130 }
 131
 132 int
 133 Session::no_roll (pframes_t nframes)
 134 {
 135         PT_TIMING_CHECK (4);
 136
 137         framepos_t end_frame = _transport_frame + nframes; // FIXME: varispeed + no_roll ??
 138         int ret = 0;
 139         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 140         boost::shared_ptr<RouteList> r = routes.reader ();
 141
 142         if (_click_io) {
 143                 _click_io->silence (nframes);
 144         }
 145
 146         ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 147
 148         VCAList v = _vca_manager->vcas ();
 149         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 150                 (*i)->automation_run (_transport_frame, nframes);
 151         }
 152
 153         if (_process_graph) {
 154                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/no-roll\n");
 155                 _process_graph->routes_no_roll( nframes, _transport_frame, end_frame, non_realtime_work_pending(), declick);
 156         } else {
 157                 PT_TIMING_CHECK (10);
 158                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 159
 160                         if ((*i)->is_auditioner()) {
 161                                 continue;
 162                         }
 163
 164                         (*i)->set_pending_declick (declick);
 165
 166                         if ((*i)->no_roll (nframes, _transport_frame, end_frame, non_realtime_work_pending())) {
 167                                 error << string_compose(_("Session: error in no roll for %1"), (*i)->name()) << endmsg;
 168                                 ret = -1;
 169                                 break;
 170                         }
 171                 }
 172                 PT_TIMING_CHECK (11);
 173         }
 174
 175         PT_TIMING_CHECK (5);
 176         return ret;
 177 }
 178
 179 /** @param need_butler to be set to true by this method if it needs the butler,
 180  *  otherwise it must be left alone.
 181  */
 182 int
 183 Session::process_routes (pframes_t nframes, bool& need_butler)
 184 {
 185         int declick = (config.get_use_transport_fades() ? get_transport_declick_required() : false);
 186         boost::shared_ptr<RouteList> r = routes.reader ();
 187
 188         const framepos_t start_frame = _transport_frame;
 189         const framepos_t end_frame = _transport_frame + floor (nframes * _transport_speed);
 190
 191         VCAList v = _vca_manager->vcas ();
 192         for (VCAList::const_iterator i = v.begin(); i != v.end(); ++i) {
 193                 (*i)->automation_run (start_frame, nframes);
 194         }
 195
 196         _global_locate_pending = locate_pending ();
 197
 198         if (_process_graph) {
 199                 DEBUG_TRACE(DEBUG::ProcessThreads,"calling graph/process-routes\n");
 200                 if (_process_graph->process_routes (nframes, start_frame, end_frame, declick, need_butler) < 0) {
 201                         stop_transport ();
 202                         return -1;
 203                 }
 204         } else {
 205
 206                 for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 207
 208                         int ret;
 209
 210                         if ((*i)->is_auditioner()) {
 211                                 continue;
 212                         }
 213
 214                         (*i)->set_pending_declick (declick);
 215
 216                         bool b = false;
 217
 218                         if ((ret = (*i)->roll (nframes, start_frame, end_frame, declick, b)) < 0) {
 219                                 stop_transport ();
 220                                 return -1;
 221                         }
 222
 223                         if (b) {
 224                                 DEBUG_TRACE (DEBUG::Butler, string_compose ("%1 rolled and needs butler\n", (*i)->name()));
 225                                 need_butler = true;
 226                         }
 227                 }
 228         }
 229
 230         return 0;
 231 }
 232
 233 void
 234 Session::get_track_statistics ()
 235 {
 236         float pworst = 1.0f;
 237         float cworst = 1.0f;
 238
 239         boost::shared_ptr<RouteList> rl = routes.reader();
 240         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 241
 242                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 243
 244                 if (!tr || tr->is_private_route()) {
 245                         continue;
 246                 }
 247
 248                 pworst = min (pworst, tr->playback_buffer_load());
 249                 cworst = min (cworst, tr->capture_buffer_load());
 250         }
 251
 252         g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
 253         g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
 254
 255         if (actively_recording()) {
 256                 set_dirty();
 257         }
 258 }
 259
 260 /** Process callback used when the auditioner is not active */
 261 void
 262 Session::process_with_events (pframes_t nframes)
 263 {
 264         PT_TIMING_CHECK (3);
 265
 266         SessionEvent*  ev;
 267         pframes_t      this_nframes;
 268         framepos_t     end_frame;
 269         bool           session_needs_butler = false;
 270         framecnt_t     frames_moved;
 271
 272         /* make sure the auditioner is silent */
 273
 274         if (auditioner) {
 275                 auditioner->silence (nframes);
 276         }
 277
 278         /* handle any pending events */
 279
 280         while (pending_events.read (&ev, 1) == 1) {
 281                 merge_event (ev);
 282         }
 283
 284         /* if we are not in the middle of a state change,
 285            and there are immediate events queued up,
 286            process them.
 287         */
 288
 289         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 290                 SessionEvent *ev = immediate_events.front ();
 291                 immediate_events.pop_front ();
 292                 process_event (ev);
 293         }
 294
 295         /* count in */
 296         if (_transport_speed != 1.0 && _count_in_samples > 0) {
 297                 _count_in_samples = 0;
 298         }
 299
 300         if (_count_in_samples > 0) {
 301                 framecnt_t ns = std::min ((framecnt_t)nframes, _count_in_samples);
 302
 303                 no_roll (ns);
 304                 run_click (_transport_frame - _count_in_samples, ns);
 305
 306                 _count_in_samples -= ns;
 307                 nframes -= ns;
 308
 309                 /* process events.. */
 310                 if (!events.empty() && next_event != events.end()) {
 311                         SessionEvent* this_event = *next_event;
 312                         Events::iterator the_next_one = next_event;
 313                         ++the_next_one;
 314
 315                         while (this_event && this_event->action_frame == _transport_frame) {
 316                                 process_event (this_event);
 317                                 if (the_next_one == events.end()) {
 318                                         this_event = 0;
 319                                 } else {
 320                                         this_event = *the_next_one;
 321                                         ++the_next_one;
 322                                 }
 323                         }
 324                         set_next_event ();
 325                 }
 326
 327                 check_declick_out ();
 328
 329                 if (nframes == 0) {
 330                         return;
 331                 } else {
 332                         _engine.split_cycle (ns);
 333                 }
 334         }
 335
 336         /* Decide on what to do with quarter-frame MTC during this cycle */
 337
 338         bool const was_sending_qf_mtc = _send_qf_mtc;
 339         double const tolerance = Config->get_mtc_qf_speed_tolerance() / 100.0;
 340
 341         if (_transport_speed != 0) {
 342                 _send_qf_mtc = (
 343                         Config->get_send_mtc () &&
 344                         _transport_speed >= (1 - tolerance) &&
 345                         _transport_speed <= (1 + tolerance)
 346                         );
 347
 348                 if (_send_qf_mtc && !was_sending_qf_mtc) {
 349                         /* we will re-start quarter-frame MTC this cycle, so send a full update to set things up */
 350                         _send_timecode_update = true;
 351                 }
 352
 353                 if (Config->get_send_mtc() && !_send_qf_mtc && _pframes_since_last_mtc > (frame_rate () / 4)) {
 354                         /* we're sending MTC, but we're not sending QF MTC at the moment, and it's been
 355                            a quarter of a second since we sent anything at all, so send a full MTC update
 356                            this cycle.
 357                         */
 358                         _send_timecode_update = true;
 359                 }
 360
 361                 _pframes_since_last_mtc += nframes;
 362         }
 363
 364         /* Events caused a transport change (or we re-started sending
 365          * MTC), so send an MTC Full Frame (Timecode) message.  This
 366          * is sent whether rolling or not, to give slaves an idea of
 367          * ardour time on locates (and allow slow slaves to position
 368          * and prepare for rolling)
 369          */
 370         if (_send_timecode_update) {
 371                 send_full_time_code (_transport_frame, nframes);
 372         }
 373
 374         if (!process_can_proceed()) {
 375                 _silent = true;
 376                 return;
 377         }
 378
 379         if (events.empty() || next_event == events.end()) {
 380                 try_run_lua (nframes); // also during export ?? ->move to process_without_events()
 381                 /* lua scripts may inject events */
 382                 while (_n_lua_scripts > 0 && pending_events.read (&ev, 1) == 1) {
 383                         merge_event (ev);
 384                 }
 385                 if (events.empty() || next_event == events.end()) {
 386                         process_without_events (nframes);
 387                         return;
 388                 }
 389         }
 390
 391         if (_transport_speed == 1.0) {
 392                 frames_moved = (framecnt_t) nframes;
 393         } else {
 394                 interpolation.set_target_speed (_target_transport_speed);
 395                 interpolation.set_speed (_transport_speed);
 396                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 397         }
 398
 399         end_frame = _transport_frame + frames_moved;
 400
 401         {
 402                 SessionEvent* this_event;
 403                 Events::iterator the_next_one;
 404
 405                 if (!process_can_proceed()) {
 406                         _silent = true;
 407                         return;
 408                 }
 409
 410                 if (!_exporting && _slave) {
 411                         if (!follow_slave (nframes)) {
 412                                 cerr << "P-w-E: FS fail\n";
 413                                 return;
 414                         }
 415                 }
 416
 417                 if (_transport_speed == 0) {
 418                         cerr << "P-w-E: ts = 0\n";
 419                         no_roll (nframes);
 420                         return;
 421                 }
 422
 423                 if (!_exporting && !timecode_transmission_suspended()) {
 424                         send_midi_time_code_for_cycle (_transport_frame, end_frame, nframes);
 425                 }
 426
 427                 ltc_tx_send_time_code_for_cycle (_transport_frame, end_frame, _target_transport_speed, _transport_speed, nframes);
 428
 429                 framepos_t stop_limit = compute_stop_limit ();
 430
 431                 if (maybe_stop (stop_limit)) {
 432                         cerr << "P-w-E: mebbe stop\n";
 433                         no_roll (nframes);
 434                         return;
 435                 }
 436
 437                 this_event = *next_event;
 438                 the_next_one = next_event;
 439                 ++the_next_one;
 440
 441                 /* yes folks, here it is, the actual loop where we really truly
 442                    process some audio
 443                 */
 444
 445                 while (nframes) {
 446
 447                         this_nframes = nframes; /* real (jack) time relative */
 448                         frames_moved = (framecnt_t) floor (_transport_speed * nframes); /* transport relative */
 449
 450                         /* running an event, position transport precisely to its time */
 451                         if (this_event && this_event->action_frame <= end_frame && this_event->action_frame >= _transport_frame) {
 452                                 /* this isn't quite right for reverse play */
 453                                 frames_moved = (framecnt_t) (this_event->action_frame - _transport_frame);
 454                                 this_nframes = abs (floor(frames_moved / _transport_speed));
 455                         }
 456
 457                         try_run_lua (this_nframes);
 458
 459                         if (this_nframes) {
 460
 461                                 click (_transport_frame, this_nframes);
 462
 463                                 if (process_routes (this_nframes, session_needs_butler)) {
 464                                         cerr << "P-w-E: PR fail\n";
 465                                         fail_roll (nframes);
 466                                         return;
 467                                 }
 468
 469                                 get_track_statistics ();
 470
 471                                 nframes -= this_nframes;
 472
 473                                 if (frames_moved < 0) {
 474                                         decrement_transport_position (-frames_moved);
 475                                 } else if (frames_moved) {
 476                                         increment_transport_position (frames_moved);
 477                                 }
 478
 479                                 cerr << "P-w-E: ts now = " << _transport_frame << endl;
 480
 481                                 maybe_stop (stop_limit);
 482                                 check_declick_out ();
 483                         }
 484
 485                         if (nframes > 0) {
 486                                 _engine.split_cycle (this_nframes);
 487                         }
 488
 489                         /* now handle this event and all others scheduled for the same time */
 490
 491                         while (this_event && this_event->action_frame == _transport_frame) {
 492                                 process_event (this_event);
 493
 494                                 if (the_next_one == events.end()) {
 495                                         this_event = 0;
 496                                 } else {
 497                                         this_event = *the_next_one;
 498                                         ++the_next_one;
 499                                 }
 500                         }
 501
 502                         /* if an event left our state changing, do the right thing */
 503
 504                         if (nframes && non_realtime_work_pending()) {
 505                                 cerr << "P-w-E: nrtwp no roll\n";
 506                                 no_roll (nframes);
 507                                 break;
 508                         }
 509
 510                         /* this is necessary to handle the case of seamless looping */
 511                         end_frame = _transport_frame + floor (nframes * _transport_speed);
 512                 }
 513
 514                 set_next_event ();
 515
 516         } /* implicit release of route lock */
 517
 518         cerr << "P-w-E: final ts = " << _transport_frame << endl;
 519
 520         if (session_needs_butler) {
 521                 DEBUG_TRACE (DEBUG::Butler, "p-with-events: session needs butler, call it\n");
 522                 _butler->summon ();
 523         }
 524 }
 525
 526 void
 527 Session::reset_slave_state ()
 528 {
 529         average_slave_delta = 1800;
 530         delta_accumulator_cnt = 0;
 531         have_first_delta_accumulator = false;
 532         _slave_state = Stopped;
 533         DiskReader::set_no_disk_output (false);
 534 }
 535
 536 bool
 537 Session::transport_locked () const
 538 {
 539         Slave* sl = _slave;
 540
 541         if (!locate_pending() && (!config.get_external_sync() || (sl && sl->ok() && sl->locked()))) {
 542                 return true;
 543         }
 544
 545         return false;
 546 }
 547
 548 bool
 549 Session::follow_slave (pframes_t nframes)
 550 {
 551         double slave_speed;
 552         framepos_t slave_transport_frame;
 553         framecnt_t this_delta;
 554         int dir;
 555
 556         if (!_slave->ok()) {
 557                 stop_transport ();
 558                 config.set_external_sync (false);
 559                 goto noroll;
 560         }
 561
 562         _slave->speed_and_position (slave_speed, slave_transport_frame);
 563
 564         DEBUG_TRACE (DEBUG::Slave, string_compose ("Slave position %1 speed %2\n", slave_transport_frame, slave_speed));
 565
 566         if (!_slave->locked()) {
 567                 DEBUG_TRACE (DEBUG::Slave, "slave not locked\n");
 568                 goto noroll;
 569         }
 570
 571         if (slave_transport_frame > _transport_frame) {
 572                 this_delta = slave_transport_frame - _transport_frame;
 573                 dir = 1;
 574         } else {
 575                 this_delta = _transport_frame - slave_transport_frame;
 576                 dir = -1;
 577         }
 578
 579         if (_slave->starting()) {
 580                 slave_speed = 0.0f;
 581         }
 582
 583         if (_slave->is_always_synced() ||
 584                         (Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)
 585                         ) {
 586
 587                 /* if the TC source is synced, then we assume that its
 588                    speed is binary: 0.0 or 1.0
 589                 */
 590
 591                 if (slave_speed != 0.0f) {
 592                         slave_speed = 1.0f;
 593                 }
 594
 595         } else {
 596
 597                 /* if we are chasing and the average delta between us and the
 598                    master gets too big, we want to switch to silent
 599                    motion. so keep track of that here.
 600                 */
 601
 602                 if (_slave_state == Running) {
 603                         calculate_moving_average_of_slave_delta(dir, abs(this_delta));
 604                 }
 605         }
 606
 607         track_slave_state (slave_speed, slave_transport_frame, this_delta);
 608
 609         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave state %1 @ %2 speed %3 cur delta %4 avg delta %5\n",
 610                                                    _slave_state, slave_transport_frame, slave_speed, this_delta, average_slave_delta));
 611
 612
 613         if (_slave_state == Running && !_slave->is_always_synced() && !(Config->get_timecode_source_is_synced() && (dynamic_cast<TimecodeSlave*>(_slave)) != 0)) {
 614
 615                 /* may need to varispeed to sync with slave */
 616
 617                 if (_transport_speed != 0.0f) {
 618
 619                         /*
 620                            note that average_dir is +1 or -1
 621                         */
 622
 623                         float delta;
 624
 625                         if (average_slave_delta == 0) {
 626                                 delta = this_delta;
 627                                 delta *= dir;
 628                         } else {
 629                                 delta = average_slave_delta;
 630                                 delta *= average_dir;
 631                         }
 632
 633 #ifndef NDEBUG
 634                         if (slave_speed != 0.0) {
 635                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("delta = %1 speed = %2 ts = %3 M@%4 S@%5 avgdelta %6\n",
 636                                                                            (int) (dir * this_delta),
 637                                                                            slave_speed,
 638                                                                            _transport_speed,
 639                                                                            _transport_frame,
 640                                                                            slave_transport_frame,
 641                                                                            average_slave_delta));
 642                         }
 643 #endif
 644
 645                         if (_slave->give_slave_full_control_over_transport_speed()) {
 646                                 set_transport_speed (slave_speed, 0, false, false);
 647                                 //std::cout << "set speed = " << slave_speed << "\n";
 648                         } else {
 649                                 float adjusted_speed = slave_speed + (1.5 * (delta /  float(_current_frame_rate)));
 650                                 request_transport_speed (adjusted_speed);
 651                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("adjust using %1 towards %2 ratio %3 current %4 slave @ %5\n",
 652                                                                            delta, adjusted_speed, adjusted_speed/slave_speed, _transport_speed,
 653                                                                            slave_speed));
 654                         }
 655
 656                         if (!actively_recording() && (framecnt_t) average_slave_delta > _slave->resolution()) {
 657                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("average slave delta %1 greater than slave resolution %2 => no disk output\n", average_slave_delta, _slave->resolution()));
 658                                 /* run routes as normal, but no disk output */
 659                                 DiskReader::set_no_disk_output (true);
 660                                 return true;
 661                         }
 662
 663                         if (!have_first_delta_accumulator) {
 664                                 DEBUG_TRACE (DEBUG::Slave, "waiting for first slave delta accumulator to be ready, no disk output\n");
 665                                 /* run routes as normal, but no disk output */
 666                                 DiskReader::set_no_disk_output (true);
 667                                 return true;
 668                         }
 669                 }
 670         }
 671
 672
 673         if (!have_first_delta_accumulator) {
 674                 DEBUG_TRACE (DEBUG::Slave, "still waiting to compute slave delta, no disk output\n");
 675                 DiskReader::set_no_disk_output (true);
 676         } else {
 677                 DiskReader::set_no_disk_output (false);
 678         }
 679
 680         if ((_slave_state == Running) && (0 == (post_transport_work () & ~PostTransportSpeed))) {
 681                 /* speed is set, we're locked, and good to go */
 682                 return true;
 683         }
 684
 685   noroll:
 686         /* don't move at all */
 687         DEBUG_TRACE (DEBUG::Slave, "no roll\n")
 688         no_roll (nframes);
 689         return false;
 690 }
 691
 692 void
 693 Session::calculate_moving_average_of_slave_delta (int dir, framecnt_t this_delta)
 694 {
 695         if (delta_accumulator_cnt >= delta_accumulator_size) {
 696                 have_first_delta_accumulator = true;
 697                 delta_accumulator_cnt = 0;
 698         }
 699
 700         if (delta_accumulator_cnt != 0 || this_delta < _current_frame_rate) {
 701                 delta_accumulator[delta_accumulator_cnt++] = (framecnt_t) dir *  (framecnt_t) this_delta;
 702         }
 703
 704         if (have_first_delta_accumulator) {
 705                 average_slave_delta = 0L;
 706                 for (int i = 0; i < delta_accumulator_size; ++i) {
 707                         average_slave_delta += delta_accumulator[i];
 708                 }
 709                 average_slave_delta /= (int32_t) delta_accumulator_size;
 710                 if (average_slave_delta < 0L) {
 711                         average_dir = -1;
 712                         average_slave_delta = average_slave_delta;
 713                 } else {
 714                         average_dir = 1;
 715                 }
 716         }
 717 }
 718
 719 void
 720 Session::track_slave_state (float slave_speed, framepos_t slave_transport_frame, framecnt_t /*this_delta*/)
 721 {
 722         if (slave_speed != 0.0f) {
 723
 724                 /* slave is running */
 725
 726                 switch (_slave_state) {
 727                 case Stopped:
 728                         if (_slave->requires_seekahead()) {
 729                                 slave_wait_end = slave_transport_frame + _slave->seekahead_distance ();
 730                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, but running, requires seekahead to %1\n", slave_wait_end));
 731                                 /* we can call locate() here because we are in process context */
 732                                 locate (slave_wait_end, false, false);
 733                                 _slave_state = Waiting;
 734
 735                         } else {
 736
 737                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped -> running at %1\n", slave_transport_frame));
 738
 739                                 memset (delta_accumulator, 0, sizeof (int32_t) * delta_accumulator_size);
 740                                 average_slave_delta = 0L;
 741
 742                                 Location* al = _locations->auto_loop_location();
 743
 744                                 if (al && play_loop && (slave_transport_frame < al->start() || slave_transport_frame > al->end())) {
 745                                         // cancel looping
 746                                         request_play_loop(false);
 747                                 }
 748
 749                                 if (slave_transport_frame != _transport_frame) {
 750                                         DEBUG_TRACE (DEBUG::Slave, string_compose ("require locate to run. eng: %1 -> sl: %2\n", _transport_frame, slave_transport_frame));
 751                                         locate (slave_transport_frame, false, false);
 752                                 }
 753                                 _slave_state = Running;
 754                         }
 755                         break;
 756
 757                 case Waiting:
 758                 default:
 759                         break;
 760                 }
 761
 762                 if (_slave_state == Waiting) {
 763
 764                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave waiting at %1\n", slave_transport_frame));
 765
 766                         if (slave_transport_frame >= slave_wait_end) {
 767
 768                                 DEBUG_TRACE (DEBUG::Slave, string_compose ("slave start at %1 vs %2\n", slave_transport_frame, _transport_frame));
 769
 770                                 _slave_state = Running;
 771
 772                                 /* now perform a "micro-seek" within the disk buffers to realign ourselves
 773                                    precisely with the master.
 774                                 */
 775
 776
 777                                 bool ok = true;
 778                                 framecnt_t frame_delta = slave_transport_frame - _transport_frame;
 779
 780                                 boost::shared_ptr<RouteList> rl = routes.reader();
 781                                 for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 782                                         boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 783                                         if (tr && !tr->can_internal_playback_seek (frame_delta)) {
 784                                                 ok = false;
 785                                                 break;
 786                                         }
 787                                 }
 788
 789                                 if (ok) {
 790                                         for (RouteList::iterator i = rl->begin(); i != rl->end(); ++i) {
 791                                                 boost::shared_ptr<Track> tr = boost::dynamic_pointer_cast<Track> (*i);
 792                                                 if (tr) {
 793                                                         tr->internal_playback_seek (frame_delta);
 794                                                 }
 795                                         }
 796                                         _transport_frame += frame_delta;
 797
 798                                 } else {
 799                                         cerr << "cannot micro-seek\n";
 800                                         /* XXX what? */
 801                                 }
 802                         }
 803                 }
 804
 805                 if (_slave_state == Running && _transport_speed == 0.0f) {
 806                         DEBUG_TRACE (DEBUG::Slave, "slave starts transport\n");
 807                         start_transport ();
 808                 }
 809
 810         } else { // slave_speed is 0
 811
 812                 /* slave has stopped */
 813
 814                 if (_transport_speed != 0.0f) {
 815                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stops transport: %1 frame %2 tf %3\n", slave_speed, slave_transport_frame, _transport_frame));
 816                         stop_transport ();
 817                 }
 818
 819                 if (slave_transport_frame != _transport_frame) {
 820                         DEBUG_TRACE (DEBUG::Slave, string_compose ("slave stopped, move to %1\n", slave_transport_frame));
 821                         force_locate (slave_transport_frame, false);
 822                 }
 823
 824                 reset_slave_state();
 825         }
 826 }
 827
 828 void
 829 Session::process_without_events (pframes_t nframes)
 830 {
 831         bool session_needs_butler = false;
 832         framecnt_t frames_moved;
 833
 834         if (!process_can_proceed()) {
 835                 _silent = true;
 836                 return;
 837         }
 838
 839         if (!_exporting && _slave) {
 840                 if (!follow_slave (nframes)) {
 841                         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame, 0, 0 , nframes);
 842                         cerr << "p-WO-E: FS fail\n";
 843                         return;
 844                 }
 845         }
 846
 847         if (_transport_speed == 0) {
 848                 cerr << "p-WO-E: ts = 0\n";
 849                 no_roll (nframes);
 850                 return;
 851         }
 852
 853         if (_transport_speed == 1.0) {
 854                 frames_moved = (framecnt_t) nframes;
 855         } else {
 856                 interpolation.set_target_speed (_target_transport_speed);
 857                 interpolation.set_speed (_transport_speed);
 858                 frames_moved = (framecnt_t) interpolation.interpolate (0, nframes, 0, 0);
 859                 cerr << "p-WO-E: current speed : " << _transport_speed << " interpolate says " << frames_moved << endl;
 860         }
 861
 862         cerr << "p-WO-E: will move " << frames_moved << endl;
 863
 864         if (!_exporting && !timecode_transmission_suspended()) {
 865                 send_midi_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, nframes);
 866         }
 867
 868         ltc_tx_send_time_code_for_cycle (_transport_frame, _transport_frame + frames_moved, _target_transport_speed, _transport_speed, nframes);
 869
 870         framepos_t const stop_limit = compute_stop_limit ();
 871
 872         if (maybe_stop (stop_limit)) {
 873                 cerr << "p-WO-E: mebbe stop\n";
 874                 no_roll (nframes);
 875                 return;
 876         }
 877
 878         if (maybe_sync_start (nframes)) {
 879                 cerr << "p-WO-E: sync start said no\n";
 880                 return;
 881         }
 882
 883         click (_transport_frame, nframes);
 884
 885         if (process_routes (nframes, session_needs_butler)) {
 886                 cerr << "p-WO-E: pr failed\n";
 887                 fail_roll (nframes);
 888                 return;
 889         }
 890
 891         get_track_statistics ();
 892
 893         if (frames_moved < 0) {
 894                 decrement_transport_position (-frames_moved);
 895         } else if (frames_moved) {
 896                 increment_transport_position (frames_moved);
 897         }
 898
 899         cerr << "p-WO-E: ts now " << _transport_frame << endl;
 900
 901         maybe_stop (stop_limit);
 902         check_declick_out ();
 903
 904         if (session_needs_butler) {
 905                 DEBUG_TRACE (DEBUG::Butler, "p-without-events: session needs butler, call it\n");
 906                 _butler->summon ();
 907         }
 908 }
 909
 910 /** Process callback used when the auditioner is active.
 911  * @param nframes number of frames to process.
 912  */
 913 void
 914 Session::process_audition (pframes_t nframes)
 915 {
 916         SessionEvent* ev;
 917         boost::shared_ptr<RouteList> r = routes.reader ();
 918
 919         for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
 920                 if (!(*i)->is_auditioner()) {
 921                         (*i)->silence (nframes);
 922                 }
 923         }
 924
 925         /* run the auditioner, and if it says we need butler service, ask for it */
 926
 927         if (auditioner->play_audition (nframes) > 0) {
 928                 DEBUG_TRACE (DEBUG::Butler, "auditioner needs butler, call it\n");
 929                 _butler->summon ();
 930         }
 931
 932         /* if using a monitor section, run it because otherwise we don't hear anything */
 933
 934         if (_monitor_out && auditioner->needs_monitor()) {
 935                 _monitor_out->monitor_run (_transport_frame, _transport_frame + nframes, nframes, false);
 936         }
 937
 938         /* handle pending events */
 939
 940         while (pending_events.read (&ev, 1) == 1) {
 941                 merge_event (ev);
 942         }
 943
 944         /* if we are not in the middle of a state change,
 945            and there are immediate events queued up,
 946            process them.
 947         */
 948
 949         while (!non_realtime_work_pending() && !immediate_events.empty()) {
 950                 SessionEvent *ev = immediate_events.front ();
 951                 immediate_events.pop_front ();
 952                 process_event (ev);
 953         }
 954
 955         if (!auditioner->auditioning()) {
 956                 /* auditioner no longer active, so go back to the normal process callback */
 957                 process_function = &Session::process_with_events;
 958         }
 959 }
 960
 961 bool
 962 Session::maybe_sync_start (pframes_t & nframes)
 963 {
 964         pframes_t sync_offset;
 965
 966         if (!waiting_for_sync_offset) {
 967                 return false;
 968         }
 969
 970         if (_engine.get_sync_offset (sync_offset) && sync_offset < nframes) {
 971
 972                 /* generate silence up to the sync point, then
 973                    adjust nframes + offset to reflect whatever
 974                    is left to do.
 975                 */
 976
 977                 no_roll (sync_offset);
 978                 nframes -= sync_offset;
 979                 Port::increment_global_port_buffer_offset (sync_offset);
 980                 waiting_for_sync_offset = false;
 981
 982                 if (nframes == 0) {
 983                         return true; // done, nothing left to process
 984                 }
 985
 986         } else {
 987
 988                 /* sync offset point is not within this process()
 989                    cycle, so just generate silence. and don't bother
 990                    with any fancy stuff here, just the minimal silence.
 991                 */
 992
 993                 _silent = true;
 994
 995                 if (Config->get_locate_while_waiting_for_sync()) {
 996                         if (micro_locate (nframes)) {
 997                                 /* XXX ERROR !!! XXX */
 998                         }
 999                 }
1000
1001                 return true; // done, nothing left to process
1002         }
1003
1004         return false;
1005 }
1006
1007 void
1008 Session::queue_event (SessionEvent* ev)
1009 {
1010         if (_state_of_the_state & Deletion) {
1011                 return;
1012         } else if (_state_of_the_state & Loading) {
1013                 merge_event (ev);
1014         } else {
1015                 Glib::Threads::Mutex::Lock lm (rb_write_lock);
1016                 pending_events.write (&ev, 1);
1017         }
1018 }
1019
1020 void
1021 Session::set_next_event ()
1022 {
1023         if (events.empty()) {
1024                 next_event = events.end();
1025                 return;
1026         }
1027
1028         if (next_event == events.end()) {
1029                 next_event = events.begin();
1030         }
1031
1032         if ((*next_event)->action_frame > _transport_frame) {
1033                 next_event = events.begin();
1034         }
1035
1036         for (; next_event != events.end(); ++next_event) {
1037                 if ((*next_event)->action_frame >= _transport_frame) {
1038                         break;
1039                 }
1040         }
1041 }
1042
1043 void
1044 Session::process_event (SessionEvent* ev)
1045 {
1046         bool remove = true;
1047         bool del = true;
1048
1049         /* if we're in the middle of a state change (i.e. waiting
1050            for the butler thread to complete the non-realtime
1051            part of the change), we'll just have to queue this
1052            event for a time when the change is complete.
1053         */
1054
1055         if (non_realtime_work_pending()) {
1056
1057                 /* except locates, which we have the capability to handle */
1058
1059                 if (ev->type != SessionEvent::Locate) {
1060                         immediate_events.insert (immediate_events.end(), ev);
1061                         _remove_event (ev);
1062                         return;
1063                 }
1064         }
1065
1066         DEBUG_TRACE (DEBUG::SessionEvents, string_compose ("Processing event: %1 @ %2\n", enum_2_string (ev->type), _transport_frame));
1067
1068         switch (ev->type) {
1069         case SessionEvent::SetLoop:
1070                 set_play_loop (ev->yes_or_no, ev->speed);
1071                 break;
1072
1073         case SessionEvent::AutoLoop:
1074                 if (play_loop) {
1075                         /* roll after locate, do not flush, set "with loop"
1076                            true only if we are seamless looping
1077                         */
1078                         start_locate (ev->target_frame, true, false, Config->get_seamless_loop());
1079                 }
1080                 remove = false;
1081                 del = false;
1082                 break;
1083
1084         case SessionEvent::AutoLoopDeclick:
1085                 if (play_loop) {
1086                         /* Request a declick fade-out and a fade-in; the fade-out will happen
1087                            at the end of the loop, and the fade-in at the start.
1088                         */
1089                         transport_sub_state |= (PendingLoopDeclickOut | PendingLoopDeclickIn);
1090                 }
1091                 remove = false;
1092                 del = false;
1093                 break;
1094
1095         case SessionEvent::Locate:
1096                 if (ev->yes_or_no) {
1097                         /* args: do not roll after locate, do flush, not with loop */
1098                         locate (ev->target_frame, false, true, false);
1099                 } else {
1100                         /* args: do not roll after locate, do flush, not with loop */
1101                         start_locate (ev->target_frame, false, true, false);
1102                 }
1103                 _send_timecode_update = true;
1104                 break;
1105
1106         case SessionEvent::LocateRoll:
1107                 if (ev->yes_or_no) {
1108                         /* args: roll after locate, do flush, not with loop */
1109                         locate (ev->target_frame, true, true, false);
1110                 } else {
1111                         /* args: roll after locate, do flush, not with loop */
1112                         start_locate (ev->target_frame, true, true, false);
1113                 }
1114                 _send_timecode_update = true;
1115                 break;
1116
1117         case SessionEvent::Skip:
1118                 if (Config->get_skip_playback()) {
1119                         start_locate (ev->target_frame, true, true, false);
1120                         _send_timecode_update = true;
1121                 }
1122                 remove = false;
1123                 del = false;
1124                 break;
1125
1126         case SessionEvent::LocateRollLocate:
1127                 // locate is handled by ::request_roll_at_and_return()
1128                 _requested_return_frame = ev->target_frame;
1129                 request_locate (ev->target2_frame, true);
1130                 break;
1131
1132
1133         case SessionEvent::SetTransportSpeed:
1134                 set_transport_speed (ev->speed, ev->target_frame, ev->yes_or_no, ev->second_yes_or_no, ev->third_yes_or_no);
1135                 break;
1136
1137         case SessionEvent::PunchIn:
1138                 // cerr << "PunchIN at " << transport_frame() << endl;
1139                 if (config.get_punch_in() && record_status() == Enabled && !preroll_record_punch_enabled()) {
1140                         enable_record ();
1141                 }
1142                 remove = false;
1143                 del = false;
1144                 break;
1145
1146         case SessionEvent::PunchOut:
1147                 // cerr << "PunchOUT at " << transport_frame() << endl;
1148                 if (config.get_punch_out() && !preroll_record_punch_enabled()) {
1149                         step_back_from_record ();
1150                 }
1151                 remove = false;
1152                 del = false;
1153                 break;
1154
1155         case SessionEvent::RecordStart:
1156                 if (preroll_record_punch_enabled() && record_status() == Enabled) {
1157                         enable_record ();
1158                 }
1159                 remove = false;
1160                 del = false;
1161                 break;
1162
1163         case SessionEvent::StopOnce:
1164                 if (!non_realtime_work_pending()) {
1165                         _clear_event_type (SessionEvent::StopOnce);
1166                         stop_transport (ev->yes_or_no);
1167                 }
1168                 remove = false;
1169                 del = false;
1170                 break;
1171
1172         case SessionEvent::RangeStop:
1173                 if (!non_realtime_work_pending()) {
1174                         stop_transport (ev->yes_or_no);
1175                 }
1176                 remove = false;
1177                 del = false;
1178                 break;
1179
1180         case SessionEvent::RangeLocate:
1181                 /* args: roll after locate, do flush, not with loop */
1182                 start_locate (ev->target_frame, true, true, false);
1183                 remove = false;
1184                 del = false;
1185                 break;
1186
1187         case SessionEvent::Overwrite:
1188                 overwrite_some_buffers (static_cast<Track*>(ev->ptr));
1189                 break;
1190
1191         case SessionEvent::SetSyncSource:
1192                 DEBUG_TRACE (DEBUG::Slave, "seen request for new slave\n");
1193                 use_sync_source (ev->slave);
1194                 break;
1195
1196         case SessionEvent::Audition:
1197                 set_audition (ev->region);
1198                 // drop reference to region
1199                 ev->region.reset ();
1200                 break;
1201
1202         case SessionEvent::SetPlayAudioRange:
1203                 set_play_range (ev->audio_range, (ev->speed == 1.0f));
1204                 break;
1205
1206         case SessionEvent::CancelPlayAudioRange:
1207                 unset_play_range();
1208                 break;
1209
1210         case SessionEvent::RealTimeOperation:
1211                 process_rtop (ev);
1212                 del = false; // other side of RT request needs to clean up
1213                 break;
1214
1215         case SessionEvent::AdjustPlaybackBuffering:
1216                 schedule_playback_buffering_adjustment ();
1217                 break;
1218
1219         case SessionEvent::AdjustCaptureBuffering:
1220                 schedule_capture_buffering_adjustment ();
1221                 break;
1222
1223         case SessionEvent::SetTimecodeTransmission:
1224                 g_atomic_int_set (&_suspend_timecode_transmission, ev->yes_or_no ? 0 : 1);
1225                 break;
1226
1227         default:
1228           fatal << string_compose(_("Programming error: illegal event type in process_event (%1)"), ev->type) << endmsg;
1229                 abort(); /*NOTREACHED*/
1230                 break;
1231         };
1232
1233         if (remove) {
1234                 del = del && !_remove_event (ev);
1235         }
1236
1237         if (del) {
1238                 delete ev;
1239         }
1240 }
1241
1242 framepos_t
1243 Session::compute_stop_limit () const
1244 {
1245         if (!Config->get_stop_at_session_end ()) {
1246                 return max_framepos;
1247         }
1248
1249         if (_slave) {
1250                 return max_framepos;
1251         }
1252
1253         if (preroll_record_punch_enabled ()) {
1254                 return max_framepos;
1255         }
1256
1257         bool const punching_in = (config.get_punch_in () && _locations->auto_punch_location());
1258         bool const punching_out = (config.get_punch_out () && _locations->auto_punch_location());
1259
1260         if (actively_recording ()) {
1261                 /* permanently recording */
1262                 return max_framepos;
1263         } else if (punching_in && !punching_out) {
1264                 /* punching in but never out */
1265                 return max_framepos;
1266         } else if (punching_in && punching_out && _locations->auto_punch_location()->end() > current_end_frame()) {
1267                 /* punching in and punching out after session end */
1268                 return max_framepos;
1269         }
1270
1271         return current_end_frame ();
1272 }
1273
1274
1275
1276 /* dedicated thread for signal emission.
1277  *
1278  * while sending cross-thread signals from the process thread
1279  * is fine in general, PBD::Signal's use of boost::function and
1280  * boost:bind can produce a vast overhead which is not
1281  * acceptable for low latency.
1282  *
1283  * This works around the issue by moving the boost overhead
1284  * out of the RT thread. The overall load is probably higher but
1285  * the realtime thread remains unaffected.
1286  */
1287
1288 void
1289 Session::emit_route_signals ()
1290 {
1291         // TODO use RAII to allow using these signals in other places
1292         BatchUpdateStart(); /* EMIT SIGNAL */
1293         boost::shared_ptr<RouteList> r = routes.reader ();
1294         for (RouteList::const_iterator ci = r->begin(); ci != r->end(); ++ci) {
1295                 (*ci)->emit_pending_signals ();
1296         }
1297         BatchUpdateEnd(); /* EMIT SIGNAL */
1298 }
1299
1300 void
1301 Session::emit_thread_start ()
1302 {
1303         if (_rt_thread_active) {
1304                 return;
1305         }
1306         _rt_thread_active = true;
1307
1308         if (pthread_create (&_rt_emit_thread, NULL, emit_thread, this)) {
1309                 _rt_thread_active = false;
1310         }
1311 }
1312
1313 void
1314 Session::emit_thread_terminate ()
1315 {
1316         if (!_rt_thread_active) {
1317                 return;
1318         }
1319         _rt_thread_active = false;
1320
1321         if (pthread_mutex_lock (&_rt_emit_mutex) == 0) {
1322                 pthread_cond_signal (&_rt_emit_cond);
1323                 pthread_mutex_unlock (&_rt_emit_mutex);
1324         }
1325
1326         void *status;
1327         pthread_join (_rt_emit_thread, &status);
1328 }
1329
1330 void *
1331 Session::emit_thread (void *arg)
1332 {
1333         Session *s = static_cast<Session *>(arg);
1334         s->emit_thread_run ();
1335         pthread_exit (0);
1336         return 0;
1337 }
1338
1339 void
1340 Session::emit_thread_run ()
1341 {
1342         pthread_mutex_lock (&_rt_emit_mutex);
1343         while (_rt_thread_active) {
1344                 emit_route_signals();
1345                 pthread_cond_wait (&_rt_emit_cond, &_rt_emit_mutex);
1346         }
1347         pthread_mutex_unlock (&_rt_emit_mutex);
1348 }