libs/ardour/diskstream.cc

   1 /*
   2     Copyright (C) 2000-2006 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 <fstream>
  21 #include <cassert>
  22 #include <cstdio>
  23 #include <unistd.h>
  24 #include <cmath>
  25 #include <cerrno>
  26 #include <string>
  27 #include <climits>
  28 #include <fcntl.h>
  29 #include <cstdlib>
  30 #include <ctime>
  31 #include <sys/stat.h>
  32
  33 #include <glibmm/threads.h>
  34
  35 #include "pbd/error.h"
  36 #include "pbd/basename.h"
  37 #include "pbd/memento_command.h"
  38 #include "pbd/xml++.h"
  39 #include "pbd/stacktrace.h"
  40
  41 #include "ardour/debug.h"
  42 #include "ardour/diskstream.h"
  43 #include "ardour/io.h"
  44 #include "ardour/pannable.h"
  45 #include "ardour/playlist.h"
  46 #include "ardour/session.h"
  47 #include "ardour/track.h"
  48
  49 #include "i18n.h"
  50 #include <locale.h>
  51
  52 using namespace std;
  53 using namespace ARDOUR;
  54 using namespace PBD;
  55
  56 ARDOUR::framecnt_t Diskstream::disk_read_chunk_frames = default_disk_read_chunk_frames ();
  57 ARDOUR::framecnt_t Diskstream::disk_write_chunk_frames = default_disk_write_chunk_frames ();
  58
  59 PBD::Signal0<void>                Diskstream::DiskOverrun;
  60 PBD::Signal0<void>                Diskstream::DiskUnderrun;
  61
  62 Diskstream::Diskstream (Session &sess, const string &name, Flag flag)
  63         : SessionObject(sess, name)
  64         , i_am_the_modifier (0)
  65         , _track (0)
  66         , _record_enabled (0)
  67             , _record_safe (0)
  68         , _visible_speed (1.0f)
  69         , _actual_speed (1.0f)
  70         , _buffer_reallocation_required (false)
  71         , _seek_required (false)
  72         , capture_start_frame (0)
  73         , capture_captured (0)
  74         , was_recording (false)
  75         , adjust_capture_position (0)
  76         , _capture_offset (0)
  77         , _roll_delay (0)
  78         , first_recordable_frame (max_framepos)
  79         , last_recordable_frame (max_framepos)
  80         , last_possibly_recording (0)
  81         , _alignment_style (ExistingMaterial)
  82         , _alignment_choice (Automatic)
  83         , _slaved (false)
  84         , loop_location (0)
  85         , overwrite_frame (0)
  86         , overwrite_offset (0)
  87         , _pending_overwrite (false)
  88         , overwrite_queued (false)
  89         , wrap_buffer_size (0)
  90         , speed_buffer_size (0)
  91         , _speed (1.0)
  92         , _target_speed (_speed)
  93         , file_frame (0)
  94         , playback_sample (0)
  95         , in_set_state (false)
  96         , _flags (flag)
  97         , deprecated_io_node (0)
  98 {
  99 }
 100
 101 Diskstream::Diskstream (Session& sess, const XMLNode& /*node*/)
 102         : SessionObject(sess, "unnamed diskstream")
 103         , i_am_the_modifier (0)
 104         , _track (0)
 105         , _record_enabled (0)
 106             , _record_safe (0)
 107         , _visible_speed (1.0f)
 108         , _actual_speed (1.0f)
 109         , _buffer_reallocation_required (false)
 110         , _seek_required (false)
 111         , capture_start_frame (0)
 112         , capture_captured (0)
 113         , was_recording (false)
 114         , adjust_capture_position (0)
 115         , _capture_offset (0)
 116         , _roll_delay (0)
 117         , first_recordable_frame (max_framepos)
 118         , last_recordable_frame (max_framepos)
 119         , last_possibly_recording (0)
 120         , _alignment_style (ExistingMaterial)
 121         , _alignment_choice (Automatic)
 122         , _slaved (false)
 123         , loop_location (0)
 124         , overwrite_frame (0)
 125         , overwrite_offset (0)
 126         , _pending_overwrite (false)
 127         , overwrite_queued (false)
 128         , wrap_buffer_size (0)
 129         , speed_buffer_size (0)
 130         , _speed (1.0)
 131         , _target_speed (_speed)
 132         , file_frame (0)
 133         , playback_sample (0)
 134         , in_set_state (false)
 135         , _flags (Recordable)
 136         , deprecated_io_node (0)
 137 {
 138 }
 139
 140 Diskstream::~Diskstream ()
 141 {
 142         DEBUG_TRACE (DEBUG::Destruction, string_compose ("Diskstream %1 deleted\n", _name));
 143
 144         if (_playlist) {
 145                 _playlist->release ();
 146         }
 147
 148         delete deprecated_io_node;
 149 }
 150
 151 void
 152 Diskstream::set_track (Track* t)
 153 {
 154         _track = t;
 155         _io = _track->input();
 156
 157         ic_connection.disconnect();
 158         _io->changed.connect_same_thread (ic_connection, boost::bind (&Diskstream::handle_input_change, this, _1, _2));
 159
 160         if (_io->n_ports() != ChanCount::ZERO) {
 161                 input_change_pending.type = IOChange::Type (IOChange::ConfigurationChanged|IOChange::ConnectionsChanged);
 162                 non_realtime_input_change ();
 163         }
 164
 165         _track->Destroyed.connect_same_thread (*this, boost::bind (&Diskstream::route_going_away, this));
 166 }
 167
 168 void
 169 Diskstream::handle_input_change (IOChange change, void * /*src*/)
 170 {
 171         Glib::Threads::Mutex::Lock lm (state_lock);
 172
 173         if (change.type & (IOChange::ConfigurationChanged|IOChange::ConnectionsChanged)) {
 174
 175                 /* rather than handle this here on a DS-by-DS basis we defer to the
 176                    session transport/butler thread, and let it tackle
 177                    as many diskstreams as need it in one shot. this avoids many repeated
 178                    takings of the audioengine process lock.
 179                 */
 180
 181                 if (!(input_change_pending.type & change.type)) {
 182                         input_change_pending.type = IOChange::Type (input_change_pending.type | change.type);
 183                         _session.request_input_change_handling ();
 184                 }
 185         }
 186 }
 187
 188 void
 189 Diskstream::non_realtime_set_speed ()
 190 {
 191         if (_buffer_reallocation_required)
 192         {
 193                 Glib::Threads::Mutex::Lock lm (state_lock);
 194                 allocate_temporary_buffers ();
 195
 196                 _buffer_reallocation_required = false;
 197         }
 198
 199         if (_seek_required) {
 200                 if (speed() != 1.0f || speed() != -1.0f) {
 201                         seek ((framepos_t) (_session.transport_frame() * (double) speed()), true);
 202                 }
 203                 else {
 204                         seek (_session.transport_frame(), true);
 205                 }
 206
 207                 _seek_required = false;
 208         }
 209 }
 210
 211 bool
 212 Diskstream::realtime_set_speed (double sp, bool global)
 213 {
 214         bool changed = false;
 215         double new_speed = sp * _session.transport_speed();
 216
 217         if (_visible_speed != sp) {
 218                 _visible_speed = sp;
 219                 changed = true;
 220         }
 221
 222         if (new_speed != _actual_speed) {
 223
 224                 framecnt_t required_wrap_size = (framecnt_t) ceil (_session.get_block_size() *
 225                                                                   fabs (new_speed)) + 2;
 226
 227                 if (required_wrap_size > wrap_buffer_size) {
 228                         _buffer_reallocation_required = true;
 229                 }
 230
 231                 _actual_speed = new_speed;
 232                 _target_speed = fabs(_actual_speed);
 233         }
 234
 235         if (changed) {
 236                 if (!global) {
 237                         _seek_required = true;
 238                 }
 239                 SpeedChanged (); /* EMIT SIGNAL */
 240         }
 241
 242         return _buffer_reallocation_required || _seek_required;
 243 }
 244
 245 void
 246 Diskstream::set_capture_offset ()
 247 {
 248         if (_io == 0) {
 249                 /* can't capture, so forget it */
 250                 return;
 251         }
 252
 253         switch (_alignment_style) {
 254         case ExistingMaterial:
 255                 _capture_offset = _io->latency();
 256                 break;
 257
 258         case CaptureTime:
 259         default:
 260                 _capture_offset = 0;
 261                 break;
 262         }
 263
 264         DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose ("%1: using IO latency, capture offset set to %2 with style = %3\n", name(), _capture_offset, enum_2_string (_alignment_style)));
 265 }
 266
 267
 268 void
 269 Diskstream::set_align_style (AlignStyle a, bool force)
 270 {
 271         if (record_enabled() && _session.actively_recording()) {
 272                 return;
 273         }
 274
 275         if ((a != _alignment_style) || force) {
 276                 _alignment_style = a;
 277                 set_capture_offset ();
 278                 AlignmentStyleChanged ();
 279         }
 280 }
 281
 282 void
 283 Diskstream::set_align_choice (AlignChoice a, bool force)
 284 {
 285         if (record_enabled() && _session.actively_recording()) {
 286                 return;
 287         }
 288
 289         if ((a != _alignment_choice) || force) {
 290                 _alignment_choice = a;
 291
 292                 switch (_alignment_choice) {
 293                         case Automatic:
 294                                 set_align_style_from_io ();
 295                                 break;
 296                         case UseExistingMaterial:
 297                                 set_align_style (ExistingMaterial);
 298                                 break;
 299                         case UseCaptureTime:
 300                                 set_align_style (CaptureTime);
 301                                 break;
 302                 }
 303         }
 304 }
 305
 306 int
 307 Diskstream::set_loop (Location *location)
 308 {
 309         if (location) {
 310                 if (location->start() >= location->end()) {
 311                         error << string_compose(_("Location \"%1\" not valid for track loop (start >= end)"), location->name()) << endl;
 312                         return -1;
 313                 }
 314         }
 315
 316         loop_location = location;
 317
 318         LoopSet (location); /* EMIT SIGNAL */
 319         return 0;
 320 }
 321
 322 /** Get the start position (in session frames) of the nth capture in the current pass */
 323 ARDOUR::framepos_t
 324 Diskstream::get_capture_start_frame (uint32_t n) const
 325 {
 326         Glib::Threads::Mutex::Lock lm (capture_info_lock);
 327
 328         if (capture_info.size() > n) {
 329                 /* this is a completed capture */
 330                 return capture_info[n]->start;
 331         } else {
 332                 /* this is the currently in-progress capture */
 333                 return capture_start_frame;
 334         }
 335 }
 336
 337 ARDOUR::framecnt_t
 338 Diskstream::get_captured_frames (uint32_t n) const
 339 {
 340         Glib::Threads::Mutex::Lock lm (capture_info_lock);
 341
 342         if (capture_info.size() > n) {
 343                 /* this is a completed capture */
 344                 return capture_info[n]->frames;
 345         } else {
 346                 /* this is the currently in-progress capture */
 347                 return capture_captured;
 348         }
 349 }
 350
 351 void
 352 Diskstream::set_roll_delay (ARDOUR::framecnt_t nframes)
 353 {
 354         _roll_delay = nframes;
 355 }
 356
 357 int
 358 Diskstream::use_playlist (boost::shared_ptr<Playlist> playlist)
 359 {
 360         if (!playlist) {
 361                 return 0;
 362         }
 363
 364         bool prior_playlist = false;
 365
 366         {
 367                 Glib::Threads::Mutex::Lock lm (state_lock);
 368
 369                 if (playlist == _playlist) {
 370                         return 0;
 371                 }
 372
 373                 playlist_connections.drop_connections ();
 374
 375                 if (_playlist) {
 376                         _playlist->release();
 377                         prior_playlist = true;
 378                 }
 379
 380                 _playlist = playlist;
 381                 _playlist->use();
 382
 383                 if (!in_set_state && recordable()) {
 384                         reset_write_sources (false);
 385                 }
 386
 387                 _playlist->ContentsChanged.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_modified, this));
 388                 _playlist->DropReferences.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_deleted, this, boost::weak_ptr<Playlist>(_playlist)));
 389                 _playlist->RangesMoved.connect_same_thread (playlist_connections, boost::bind (&Diskstream::playlist_ranges_moved, this, _1, _2));
 390         }
 391
 392         /* don't do this if we've already asked for it *or* if we are setting up
 393            the diskstream for the very first time - the input changed handling will
 394            take care of the buffer refill.
 395         */
 396
 397         if (!overwrite_queued && prior_playlist) {
 398                 _session.request_overwrite_buffer (_track);
 399                 overwrite_queued = true;
 400         }
 401
 402         PlaylistChanged (); /* EMIT SIGNAL */
 403         _session.set_dirty ();
 404
 405         return 0;
 406 }
 407
 408 void
 409 Diskstream::playlist_changed (const PropertyChange&)
 410 {
 411         playlist_modified ();
 412 }
 413
 414 void
 415 Diskstream::playlist_modified ()
 416 {
 417         if (!i_am_the_modifier && !overwrite_queued) {
 418                 _session.request_overwrite_buffer (_track);
 419                 overwrite_queued = true;
 420         }
 421 }
 422
 423 void
 424 Diskstream::playlist_deleted (boost::weak_ptr<Playlist> wpl)
 425 {
 426         boost::shared_ptr<Playlist> pl (wpl.lock());
 427
 428         if (pl == _playlist) {
 429
 430                 /* this catches an ordering issue with session destruction. playlists
 431                    are destroyed before diskstreams. we have to invalidate any handles
 432                    we have to the playlist.
 433                 */
 434
 435                 if (_playlist) {
 436                         _playlist.reset ();
 437                 }
 438         }
 439 }
 440
 441 bool
 442 Diskstream::set_name (const string& str)
 443 {
 444         if (_name != str) {
 445                 assert(playlist());
 446                 playlist()->set_name (str);
 447                 SessionObject::set_name(str);
 448         }
 449         return true;
 450 }
 451
 452 bool
 453 Diskstream::set_write_source_name (const std::string& str) {
 454         _write_source_name = str;
 455         return true;
 456 }
 457
 458 XMLNode&
 459 Diskstream::get_state ()
 460 {
 461         XMLNode* node = new XMLNode ("Diskstream");
 462         char buf[64];
 463         LocaleGuard lg (X_("C"));
 464
 465         node->add_property ("flags", enum_2_string (_flags));
 466         node->add_property ("playlist", _playlist->name());
 467         node->add_property("name", _name);
 468         id().print (buf, sizeof (buf));
 469         node->add_property("id", buf);
 470         snprintf (buf, sizeof(buf), "%f", _visible_speed);
 471         node->add_property ("speed", buf);
 472         node->add_property ("capture-alignment", enum_2_string (_alignment_choice));
 473         node->add_property ("record-safe", _record_safe ? "yes" : "no");
 474
 475         if (_extra_xml) {
 476                 node->add_child_copy (*_extra_xml);
 477         }
 478
 479         return *node;
 480 }
 481
 482 int
 483 Diskstream::set_state (const XMLNode& node, int /*version*/)
 484 {
 485         const XMLProperty* prop;
 486
 487         if ((prop = node.property ("name")) != 0) {
 488                 _name = prop->value();
 489         }
 490
 491         if (deprecated_io_node) {
 492                 set_id (*deprecated_io_node);
 493         } else {
 494                 set_id (node);
 495         }
 496
 497         if ((prop = node.property ("flags")) != 0) {
 498                 _flags = Flag (string_2_enum (prop->value(), _flags));
 499         }
 500
 501         if ((prop = node.property (X_("capture-alignment"))) != 0) {
 502                 set_align_choice (AlignChoice (string_2_enum (prop->value(), _alignment_choice)), true);
 503         } else {
 504                 set_align_choice (Automatic, true);
 505         }
 506
 507         if ((prop = node.property ("playlist")) == 0) {
 508                 return -1;
 509         }
 510
 511         if (find_and_use_playlist (prop->value())) {
 512                 return -1;
 513         }
 514
 515         if ((prop = node.property ("speed")) != 0) {
 516                 double sp = atof (prop->value().c_str());
 517
 518                 if (realtime_set_speed (sp, false)) {
 519                         non_realtime_set_speed ();
 520                 }
 521         }
 522
 523         if ((prop = node.property ("record-safe")) != 0) {
 524             _record_safe = PBD::string_is_affirmative (prop->value()) ? 1 : 0;
 525         }
 526
 527         return 0;
 528 }
 529
 530 void
 531 Diskstream::playlist_ranges_moved (list< Evoral::RangeMove<framepos_t> > const & movements_frames, bool from_undo)
 532 {
 533         /* If we're coming from an undo, it will have handled
 534            automation undo (it must, since automation-follows-regions
 535            can lose automation data).  Hence we can do nothing here.
 536         */
 537
 538         if (from_undo) {
 539                 return;
 540         }
 541
 542         if (!_track || Config->get_automation_follows_regions () == false) {
 543                 return;
 544         }
 545
 546         list< Evoral::RangeMove<double> > movements;
 547
 548         for (list< Evoral::RangeMove<framepos_t> >::const_iterator i = movements_frames.begin();
 549              i != movements_frames.end();
 550              ++i) {
 551
 552                 movements.push_back(Evoral::RangeMove<double>(i->from, i->length, i->to));
 553         }
 554
 555         /* move panner automation */
 556         boost::shared_ptr<Pannable> pannable = _track->pannable();
 557         Evoral::ControlSet::Controls& c (pannable->controls());
 558
 559         for (Evoral::ControlSet::Controls::iterator ci = c.begin(); ci != c.end(); ++ci) {
 560                 boost::shared_ptr<AutomationControl> ac = boost::dynamic_pointer_cast<AutomationControl>(ci->second);
 561                 if (!ac) {
 562                         continue;
 563                 }
 564                 boost::shared_ptr<AutomationList> alist = ac->alist();
 565
 566                 XMLNode & before = alist->get_state ();
 567                 bool const things_moved = alist->move_ranges (movements);
 568                 if (things_moved) {
 569                         _session.add_command (new MementoCommand<AutomationList> (
 570                                                       *alist.get(), &before, &alist->get_state ()));
 571                 }
 572         }
 573
 574         /* move processor automation */
 575         _track->foreach_processor (boost::bind (&Diskstream::move_processor_automation, this, _1, movements_frames));
 576 }
 577
 578 void
 579 Diskstream::move_processor_automation (boost::weak_ptr<Processor> p, list< Evoral::RangeMove<framepos_t> > const & movements_frames)
 580 {
 581         boost::shared_ptr<Processor> processor (p.lock ());
 582         if (!processor) {
 583                 return;
 584         }
 585
 586         list< Evoral::RangeMove<double> > movements;
 587         for (list< Evoral::RangeMove<framepos_t> >::const_iterator i = movements_frames.begin(); i != movements_frames.end(); ++i) {
 588                 movements.push_back(Evoral::RangeMove<double>(i->from, i->length, i->to));
 589         }
 590
 591         set<Evoral::Parameter> const a = processor->what_can_be_automated ();
 592
 593         for (set<Evoral::Parameter>::const_iterator i = a.begin (); i != a.end (); ++i) {
 594                 boost::shared_ptr<AutomationList> al = processor->automation_control(*i)->alist();
 595                 XMLNode & before = al->get_state ();
 596                 bool const things_moved = al->move_ranges (movements);
 597                 if (things_moved) {
 598                         _session.add_command (
 599                                 new MementoCommand<AutomationList> (
 600                                         *al.get(), &before, &al->get_state ()
 601                                         )
 602                                 );
 603                 }
 604         }
 605 }
 606
 607 void
 608 Diskstream::check_record_status (framepos_t transport_frame, bool can_record)
 609 {
 610         int possibly_recording;
 611         int rolling;
 612         int change;
 613         const int transport_rolling = 0x4;
 614         const int track_rec_enabled = 0x2;
 615         const int global_rec_enabled = 0x1;
 616         const int fully_rec_enabled = (transport_rolling|track_rec_enabled|global_rec_enabled);
 617
 618         /* merge together the 3 factors that affect record status, and compute
 619          * what has changed.
 620          */
 621
 622         rolling = _session.transport_speed() != 0.0f;
 623         possibly_recording = (rolling << 2) | ((int)record_enabled() << 1) | (int)can_record;
 624         change = possibly_recording ^ last_possibly_recording;
 625
 626         if (possibly_recording == last_possibly_recording) {
 627                 return;
 628         }
 629
 630         const framecnt_t existing_material_offset = _session.worst_playback_latency();
 631
 632         if (possibly_recording == fully_rec_enabled) {
 633
 634                 if (last_possibly_recording == fully_rec_enabled) {
 635                         return;
 636                 }
 637
 638                 capture_start_frame = _session.transport_frame();
 639                 first_recordable_frame = capture_start_frame + _capture_offset;
 640                 last_recordable_frame = max_framepos;
 641
 642                 DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose ("%1: @ %7 (%9) FRF = %2 CSF = %4 CO = %5, EMO = %6 RD = %8 WOL %10 WTL %11\n",
 643                                                                       name(), first_recordable_frame, last_recordable_frame, capture_start_frame,
 644                                                                       _capture_offset,
 645                                                                       existing_material_offset,
 646                                                                       transport_frame,
 647                                                                       _roll_delay,
 648                                                                       _session.transport_frame(),
 649                                                                       _session.worst_output_latency(),
 650                                                                       _session.worst_track_latency()));
 651
 652
 653                 if (_alignment_style == ExistingMaterial) {
 654                         first_recordable_frame += existing_material_offset;
 655                         DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose ("\tshift FRF by EMO %1\n",
 656                                                                               first_recordable_frame));
 657                 }
 658
 659                 prepare_record_status (capture_start_frame);
 660
 661         } else {
 662
 663                 if (last_possibly_recording == fully_rec_enabled) {
 664
 665                         /* we were recording last time */
 666
 667                         if (change & transport_rolling) {
 668
 669                                 /* transport-change (stopped rolling): last_recordable_frame was set in ::prepare_to_stop(). We
 670                                  * had to set it there because we likely rolled past the stopping point to declick out,
 671                                  * and then backed up.
 672                                  */
 673
 674                         } else {
 675                                 /* punch out */
 676
 677                                 last_recordable_frame = _session.transport_frame() + _capture_offset;
 678
 679                                 if (_alignment_style == ExistingMaterial) {
 680                                         last_recordable_frame += existing_material_offset;
 681                                 }
 682                         }
 683                 }
 684         }
 685
 686         last_possibly_recording = possibly_recording;
 687 }
 688
 689 void
 690 Diskstream::route_going_away ()
 691 {
 692         _io.reset ();
 693 }
 694
 695 void
 696 Diskstream::calculate_record_range (Evoral::OverlapType ot, framepos_t transport_frame, framecnt_t nframes,
 697                                     framecnt_t & rec_nframes, framecnt_t & rec_offset)
 698 {
 699         switch (ot) {
 700         case Evoral::OverlapNone:
 701                 rec_nframes = 0;
 702                 break;
 703
 704         case Evoral::OverlapInternal:
 705                 /*     ----------    recrange
 706                  *       |---|       transrange
 707                  */
 708                 rec_nframes = nframes;
 709                 rec_offset = 0;
 710                 break;
 711
 712         case Evoral::OverlapStart:
 713                 /*    |--------|    recrange
 714                  *  -----|          transrange
 715                  */
 716                 rec_nframes = transport_frame + nframes - first_recordable_frame;
 717                 if (rec_nframes) {
 718                         rec_offset = first_recordable_frame - transport_frame;
 719                 }
 720                 break;
 721
 722         case Evoral::OverlapEnd:
 723                 /*    |--------|    recrange
 724                  *       |--------  transrange
 725                  */
 726                 rec_nframes = last_recordable_frame - transport_frame;
 727                 rec_offset = 0;
 728                 break;
 729
 730         case Evoral::OverlapExternal:
 731                 /*    |--------|    recrange
 732                  *  --------------  transrange
 733                  */
 734                 rec_nframes = last_recordable_frame - first_recordable_frame;
 735                 rec_offset = first_recordable_frame - transport_frame;
 736                 break;
 737         }
 738
 739         DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose ("%1 rec? %2 @ %3 (for %4) FRF %5 LRF %6 : rf %7 @ %8\n",
 740                                                               _name, enum_2_string (ot), transport_frame, nframes,
 741                                                               first_recordable_frame, last_recordable_frame, rec_nframes, rec_offset));
 742 }
 743
 744 void
 745 Diskstream::prepare_to_stop (framepos_t transport_frame, framepos_t audible_frame)
 746 {
 747         switch (_alignment_style) {
 748         case ExistingMaterial:
 749                 last_recordable_frame = transport_frame + _capture_offset;
 750                 DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose("%1: prepare to stop sets last recordable frame to %2 + %3 = %4\n", _name, transport_frame, _capture_offset, last_recordable_frame));
 751                 break;
 752
 753         case CaptureTime:
 754                 last_recordable_frame = audible_frame; // note that capture_offset is zero
 755                 /* we may already have captured audio before the last_recordable_frame (audible frame),
 756                    so deal with this.
 757                 */
 758                 if (last_recordable_frame > capture_start_frame) {
 759                         capture_captured = min (capture_captured, last_recordable_frame - capture_start_frame);
 760                 }
 761                 DEBUG_TRACE (DEBUG::CaptureAlignment, string_compose("%1: prepare to stop sets last recordable frame to audible frame @ %2\n", _name, audible_frame));
 762                 break;
 763         }
 764
 765 }
 766
 767 void
 768 Diskstream::engage_record_enable ()
 769 {
 770         g_atomic_int_set (&_record_enabled, 1);
 771 }
 772
 773 void
 774 Diskstream::disengage_record_enable ()
 775 {
 776         g_atomic_int_set (&_record_enabled, 0);
 777 }
 778
 779 void
 780 Diskstream::engage_record_safe ()
 781 {
 782         g_atomic_int_set (&_record_safe, 1);
 783 }
 784
 785 void
 786 Diskstream::disengage_record_safe ()
 787 {
 788         g_atomic_int_set (&_record_safe, 0);
 789 }
 790
 791 framecnt_t
 792 Diskstream::default_disk_read_chunk_frames()
 793 {
 794         return 65536;
 795 }
 796
 797 framecnt_t
 798 Diskstream::default_disk_write_chunk_frames ()
 799 {
 800         return 65536;
 801 }