libs/backends/portaudio/portaudio_backend.cc

   1 /*
   2  * Copyright (C) 2015-2015 Robin Gareus <robin@gareus.org>
   3  * Copyright (C) 2013 Paul Davis
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 #include <regex.h>
  21
  22 #ifndef PLATFORM_WINDOWS
  23 #include <sys/mman.h>
  24 #include <sys/time.h>
  25 #endif
  26
  27 #ifdef COMPILER_MINGW
  28 #include <sys/time.h>
  29 #endif
  30
  31 #include <glibmm.h>
  32
  33 #include "portaudio_backend.h"
  34
  35 #include "pbd/compose.h"
  36 #include "pbd/error.h"
  37 #include "pbd/file_utils.h"
  38 #include "pbd/pthread_utils.h"
  39 #include "pbd/windows_timer_utils.h"
  40 #include "pbd/windows_mmcss.h"
  41
  42 #include "ardour/filesystem_paths.h"
  43 #include "ardour/port_manager.h"
  44 #include "pbd/i18n.h"
  45
  46 #include "audio_utils.h"
  47
  48 #include "debug.h"
  49
  50 using namespace ARDOUR;
  51
  52 namespace {
  53
  54 const char * const winmme_driver_name = X_("WinMME");
  55
  56 }
  57
  58 static std::string s_instance_name;
  59 size_t PortAudioBackend::_max_buffer_size = 8192;
  60 std::vector<std::string> PortAudioBackend::_midi_options;
  61 std::vector<AudioBackend::DeviceStatus> PortAudioBackend::_input_audio_device_status;
  62 std::vector<AudioBackend::DeviceStatus> PortAudioBackend::_output_audio_device_status;
  63
  64 PortAudioBackend::PortAudioBackend (AudioEngine& e, AudioBackendInfo& info)
  65         : AudioBackend (e, info)
  66         , _pcmio (0)
  67         , _run (false)
  68         , _active (false)
  69         , _use_blocking_api(false)
  70         , _freewheel (false)
  71         , _freewheeling (false)
  72         , _freewheel_ack (false)
  73         , _reinit_thread_callback (false)
  74         , _measure_latency (false)
  75         , _cycle_count(0)
  76         , _total_deviation_us(0)
  77         , _max_deviation_us(0)
  78         , _input_audio_device("")
  79         , _output_audio_device("")
  80         , _midi_driver_option(get_standard_device_name(DeviceNone))
  81         , _samplerate (48000)
  82         , _samples_per_period (1024)
  83         , _n_inputs (0)
  84         , _n_outputs (0)
  85         , _systemic_audio_input_latency (0)
  86         , _systemic_audio_output_latency (0)
  87         , _dsp_load (0)
  88         , _processed_samples (0)
  89         , _port_change_flag (false)
  90 {
  91         _instance_name = s_instance_name;
  92         pthread_mutex_init (&_port_callback_mutex, 0);
  93         pthread_mutex_init (&_freewheel_mutex, 0);
  94         pthread_cond_init (&_freewheel_signal, 0);
  95
  96         _port_connection_queue.reserve (128);
  97
  98         _pcmio = new PortAudioIO ();
  99         _midiio = new WinMMEMidiIO ();
 100 }
 101
 102 PortAudioBackend::~PortAudioBackend ()
 103 {
 104         delete _pcmio; _pcmio = 0;
 105         delete _midiio; _midiio = 0;
 106
 107         pthread_mutex_destroy (&_port_callback_mutex);
 108         pthread_mutex_destroy (&_freewheel_mutex);
 109         pthread_cond_destroy (&_freewheel_signal);
 110 }
 111
 112 /* AUDIOBACKEND API */
 113
 114 std::string
 115 PortAudioBackend::name () const
 116 {
 117         return X_("PortAudio");
 118 }
 119
 120 bool
 121 PortAudioBackend::is_realtime () const
 122 {
 123         return true;
 124 }
 125
 126 bool
 127 PortAudioBackend::requires_driver_selection() const
 128 {
 129         // we could do this but implementation would need changing
 130         /*
 131         if (enumerate_drivers().size() == 1) {
 132                 return false;
 133         }
 134         */
 135         return true;
 136 }
 137
 138 std::vector<std::string>
 139 PortAudioBackend::enumerate_drivers () const
 140 {
 141         DEBUG_AUDIO ("Portaudio: enumerate_drivers\n");
 142         std::vector<std::string> currently_available;
 143         _pcmio->host_api_list (currently_available);
 144         return currently_available;
 145 }
 146
 147 int
 148 PortAudioBackend::set_driver (const std::string& name)
 149 {
 150         DEBUG_AUDIO (string_compose ("Portaudio: set_driver %1 \n", name));
 151         if (!_pcmio->set_host_api (name)) {
 152                 DEBUG_AUDIO (string_compose ("Portaudio: Unable to set_driver %1 \n", name));
 153                 return -1;
 154         }
 155         _pcmio->update_devices();
 156         return 0;
 157 }
 158
 159 bool
 160 PortAudioBackend::update_devices ()
 161 {
 162         // update midi device info?
 163         return _pcmio->update_devices();
 164 }
 165
 166 void
 167 PortAudioBackend::set_use_buffered_io (bool use_buffered_io)
 168 {
 169         DEBUG_AUDIO (string_compose ("Portaudio: use_buffered_io %1 \n", use_buffered_io));
 170
 171         if (running()) {
 172                 return;
 173         }
 174
 175         _use_blocking_api = use_buffered_io;
 176 }
 177
 178 std::string
 179 PortAudioBackend::driver_name () const
 180 {
 181         std::string driver_name = _pcmio->get_host_api ();
 182         DEBUG_AUDIO (string_compose ("Portaudio: driver_name %1 \n", driver_name));
 183         return driver_name;
 184 }
 185
 186 bool
 187 PortAudioBackend::use_separate_input_and_output_devices () const
 188 {
 189         return true;
 190 }
 191
 192 std::vector<AudioBackend::DeviceStatus>
 193 PortAudioBackend::enumerate_devices () const
 194 {
 195         DEBUG_AUDIO ("Portaudio: ERROR enumerate devices should not be called \n");
 196         return std::vector<AudioBackend::DeviceStatus>();
 197 }
 198
 199 std::vector<AudioBackend::DeviceStatus>
 200 PortAudioBackend::enumerate_input_devices () const
 201 {
 202         _input_audio_device_status.clear();
 203         std::map<int, std::string> input_devices;
 204         _pcmio->input_device_list(input_devices);
 205
 206         for (std::map<int, std::string>::const_iterator i = input_devices.begin (); i != input_devices.end(); ++i) {
 207                 if (_input_audio_device == "") _input_audio_device = i->second;
 208                 _input_audio_device_status.push_back (DeviceStatus (i->second, true));
 209         }
 210         return _input_audio_device_status;
 211 }
 212
 213 std::vector<AudioBackend::DeviceStatus>
 214 PortAudioBackend::enumerate_output_devices () const
 215 {
 216         _output_audio_device_status.clear();
 217         std::map<int, std::string> output_devices;
 218         _pcmio->output_device_list(output_devices);
 219
 220         for (std::map<int, std::string>::const_iterator i = output_devices.begin (); i != output_devices.end(); ++i) {
 221                 if (_output_audio_device == "") _output_audio_device = i->second;
 222                 _output_audio_device_status.push_back (DeviceStatus (i->second, true));
 223         }
 224         return _output_audio_device_status;
 225 }
 226
 227 std::vector<float>
 228 PortAudioBackend::available_sample_rates (const std::string&) const
 229 {
 230         DEBUG_AUDIO ("Portaudio: available_sample_rates\n");
 231         std::vector<float> sr;
 232         _pcmio->available_sample_rates(name_to_id(_input_audio_device), sr);
 233         return sr;
 234 }
 235
 236 std::vector<uint32_t>
 237 PortAudioBackend::available_buffer_sizes (const std::string&) const
 238 {
 239         DEBUG_AUDIO ("Portaudio: available_buffer_sizes\n");
 240         std::vector<uint32_t> bs;
 241         _pcmio->available_buffer_sizes(name_to_id(_input_audio_device), bs);
 242         return bs;
 243 }
 244
 245 uint32_t
 246 PortAudioBackend::available_input_channel_count (const std::string&) const
 247 {
 248         return 128; // TODO query current device
 249 }
 250
 251 uint32_t
 252 PortAudioBackend::available_output_channel_count (const std::string&) const
 253 {
 254         return 128; // TODO query current device
 255 }
 256
 257 bool
 258 PortAudioBackend::can_change_sample_rate_when_running () const
 259 {
 260         return false;
 261 }
 262
 263 bool
 264 PortAudioBackend::can_change_buffer_size_when_running () const
 265 {
 266         return false; // TODO
 267 }
 268
 269 int
 270 PortAudioBackend::set_device_name (const std::string& d)
 271 {
 272         DEBUG_AUDIO ("Portaudio: set_device_name should not be called\n");
 273         return 0;
 274 }
 275
 276 int
 277 PortAudioBackend::set_input_device_name (const std::string& d)
 278 {
 279         DEBUG_AUDIO (string_compose ("Portaudio: set_input_device_name %1\n", d));
 280         _input_audio_device = d;
 281         return 0;
 282 }
 283
 284 int
 285 PortAudioBackend::set_output_device_name (const std::string& d)
 286 {
 287         DEBUG_AUDIO (string_compose ("Portaudio: set_output_device_name %1\n", d));
 288         _output_audio_device = d;
 289         return 0;
 290 }
 291
 292 int
 293 PortAudioBackend::set_sample_rate (float sr)
 294 {
 295         if (sr <= 0) { return -1; }
 296         // TODO check if it's in the list of valid SR
 297         _samplerate = sr;
 298         engine.sample_rate_change (sr);
 299         return 0;
 300 }
 301
 302 int
 303 PortAudioBackend::set_buffer_size (uint32_t bs)
 304 {
 305         if (bs <= 0 || bs >= _max_buffer_size) {
 306                 return -1;
 307         }
 308         _samples_per_period = bs;
 309         engine.buffer_size_change (bs);
 310         return 0;
 311 }
 312
 313 int
 314 PortAudioBackend::set_interleaved (bool yn)
 315 {
 316         if (!yn) { return 0; }
 317         return -1;
 318 }
 319
 320 int
 321 PortAudioBackend::set_input_channels (uint32_t cc)
 322 {
 323         _n_inputs = cc;
 324         return 0;
 325 }
 326
 327 int
 328 PortAudioBackend::set_output_channels (uint32_t cc)
 329 {
 330         _n_outputs = cc;
 331         return 0;
 332 }
 333
 334 int
 335 PortAudioBackend::set_systemic_input_latency (uint32_t sl)
 336 {
 337         _systemic_audio_input_latency = sl;
 338         return 0;
 339 }
 340
 341 int
 342 PortAudioBackend::set_systemic_output_latency (uint32_t sl)
 343 {
 344         _systemic_audio_output_latency = sl;
 345         return 0;
 346 }
 347
 348 int
 349 PortAudioBackend::set_systemic_midi_input_latency (std::string const device, uint32_t sl)
 350 {
 351         MidiDeviceInfo* nfo = midi_device_info (device);
 352         if (!nfo) return -1;
 353         nfo->systemic_input_latency = sl;
 354         return 0;
 355 }
 356
 357 int
 358 PortAudioBackend::set_systemic_midi_output_latency (std::string const device, uint32_t sl)
 359 {
 360         MidiDeviceInfo* nfo = midi_device_info (device);
 361         if (!nfo) return -1;
 362         nfo->systemic_output_latency = sl;
 363         return 0;
 364 }
 365
 366 /* Retrieving parameters */
 367 std::string
 368 PortAudioBackend::device_name () const
 369 {
 370         return "Unused";
 371 }
 372
 373 std::string
 374 PortAudioBackend::input_device_name () const
 375 {
 376         return _input_audio_device;
 377 }
 378
 379 std::string
 380 PortAudioBackend::output_device_name () const
 381 {
 382         return _output_audio_device;
 383 }
 384
 385 float
 386 PortAudioBackend::sample_rate () const
 387 {
 388         return _samplerate;
 389 }
 390
 391 uint32_t
 392 PortAudioBackend::buffer_size () const
 393 {
 394         return _samples_per_period;
 395 }
 396
 397 bool
 398 PortAudioBackend::interleaved () const
 399 {
 400         return false;
 401 }
 402
 403 uint32_t
 404 PortAudioBackend::input_channels () const
 405 {
 406         return _n_inputs;
 407 }
 408
 409 uint32_t
 410 PortAudioBackend::output_channels () const
 411 {
 412         return _n_outputs;
 413 }
 414
 415 uint32_t
 416 PortAudioBackend::systemic_input_latency () const
 417 {
 418         return _systemic_audio_input_latency;
 419 }
 420
 421 uint32_t
 422 PortAudioBackend::systemic_output_latency () const
 423 {
 424         return _systemic_audio_output_latency;
 425 }
 426
 427 uint32_t
 428 PortAudioBackend::systemic_midi_input_latency (std::string const device) const
 429 {
 430         MidiDeviceInfo* nfo = midi_device_info (device);
 431         if (!nfo) return 0;
 432         return nfo->systemic_input_latency;
 433 }
 434
 435 uint32_t
 436 PortAudioBackend::systemic_midi_output_latency (std::string const device) const
 437 {
 438         MidiDeviceInfo* nfo = midi_device_info (device);
 439         if (!nfo) return 0;
 440         return nfo->systemic_output_latency;
 441 }
 442
 443 std::string
 444 PortAudioBackend::control_app_name () const
 445 {
 446         return _pcmio->control_app_name (name_to_id (_input_audio_device));
 447 }
 448
 449 void
 450 PortAudioBackend::launch_control_app ()
 451 {
 452         return _pcmio->launch_control_app (name_to_id(_input_audio_device));
 453 }
 454
 455 /* MIDI */
 456
 457 std::vector<std::string>
 458 PortAudioBackend::enumerate_midi_options () const
 459 {
 460         if (_midi_options.empty()) {
 461                 _midi_options.push_back (winmme_driver_name);
 462                 _midi_options.push_back (get_standard_device_name(DeviceNone));
 463         }
 464         return _midi_options;
 465 }
 466
 467 int
 468 PortAudioBackend::set_midi_option (const std::string& opt)
 469 {
 470         if (opt != get_standard_device_name(DeviceNone) && opt != winmme_driver_name) {
 471                 return -1;
 472         }
 473         DEBUG_MIDI (string_compose ("Setting midi option to %1\n", opt));
 474         _midi_driver_option = opt;
 475         return 0;
 476 }
 477
 478 std::string
 479 PortAudioBackend::midi_option () const
 480 {
 481         return _midi_driver_option;
 482 }
 483
 484 std::vector<AudioBackend::DeviceStatus>
 485 PortAudioBackend::enumerate_midi_devices () const
 486 {
 487         std::vector<AudioBackend::DeviceStatus> midi_device_status;
 488         std::vector<MidiDeviceInfo*> device_info;
 489
 490         if (_midi_driver_option == winmme_driver_name) {
 491                 _midiio->update_device_info ();
 492                 device_info = _midiio->get_device_info ();
 493         }
 494
 495         for (std::vector<MidiDeviceInfo*>::const_iterator i = device_info.begin();
 496              i != device_info.end();
 497              ++i) {
 498                 midi_device_status.push_back(DeviceStatus((*i)->device_name, true));
 499         }
 500         return midi_device_status;
 501 }
 502
 503 MidiDeviceInfo*
 504 PortAudioBackend::midi_device_info (const std::string& device_name) const
 505 {
 506         std::vector<MidiDeviceInfo*> dev_info;
 507
 508         if (_midi_driver_option == winmme_driver_name) {
 509                 dev_info = _midiio->get_device_info();
 510
 511                 for (std::vector<MidiDeviceInfo*>::const_iterator i = dev_info.begin();
 512                      i != dev_info.end();
 513                      ++i) {
 514                         if ((*i)->device_name == device_name) {
 515                                 return *i;
 516                         }
 517                 }
 518         }
 519         return 0;
 520 }
 521
 522 int
 523 PortAudioBackend::set_midi_device_enabled (std::string const device, bool enable)
 524 {
 525         MidiDeviceInfo* nfo = midi_device_info(device);
 526         if (!nfo) return -1;
 527         nfo->enable = enable;
 528         return 0;
 529 }
 530
 531 bool
 532 PortAudioBackend::midi_device_enabled (std::string const device) const
 533 {
 534         MidiDeviceInfo* nfo = midi_device_info(device);
 535         if (!nfo) return false;
 536         return nfo->enable;
 537 }
 538
 539 /* State Control */
 540
 541 static void * blocking_thread_func (void *arg)
 542 {
 543         PortAudioBackend *d = static_cast<PortAudioBackend *>(arg);
 544         d->blocking_process_thread ();
 545         pthread_exit (0);
 546         return 0;
 547 }
 548
 549 bool
 550 PortAudioBackend::engine_halted ()
 551 {
 552         return !_active && _run;
 553 }
 554
 555 bool
 556 PortAudioBackend::running ()
 557 {
 558         return _active || _run;
 559 }
 560
 561 int
 562 PortAudioBackend::_start (bool for_latency_measurement)
 563 {
 564         if (engine_halted()) {
 565                 stop();
 566         }
 567
 568         if (running()) {
 569                 DEBUG_AUDIO("Already started.\n");
 570                 return BackendReinitializationError;
 571         }
 572
 573         if (_ports.size()) {
 574                 DEBUG_AUDIO(
 575                     "Recovering from unclean shutdown, port registry is not empty.\n");
 576                 _system_inputs.clear();
 577                 _system_outputs.clear();
 578                 _system_midi_in.clear();
 579                 _system_midi_out.clear();
 580                 _ports.clear();
 581         }
 582
 583         /* reset internal state */
 584         assert (_run == false);
 585         _run = false;
 586         _dsp_load = 0;
 587         _freewheeling = false;
 588         _freewheel = false;
 589
 590         PaErrorCode err = paNoError;
 591
 592         if (_use_blocking_api) {
 593                 DEBUG_AUDIO("Opening blocking audio stream\n");
 594                 err = _pcmio->open_blocking_stream(name_to_id(_input_audio_device),
 595                                                    name_to_id(_output_audio_device),
 596                                                    _samplerate,
 597                                                    _samples_per_period);
 598         } else {
 599                 DEBUG_AUDIO("Opening callback audio stream\n");
 600                 err = _pcmio->open_callback_stream(name_to_id(_input_audio_device),
 601                                                    name_to_id(_output_audio_device),
 602                                                    _samplerate,
 603                                                    _samples_per_period,
 604                                                    portaudio_callback,
 605                                                    this);
 606         }
 607
 608         // reintepret Portaudio error messages
 609         switch (err) {
 610         case paNoError:
 611                 break;
 612         case paBadIODeviceCombination:
 613                 return DeviceConfigurationNotSupportedError;
 614         case paInvalidChannelCount:
 615                 return ChannelCountNotSupportedError;
 616         case paInvalidSampleRate:
 617                 return SampleRateNotSupportedError;
 618         default:
 619                 return AudioDeviceOpenError;
 620         }
 621
 622         if (_n_outputs != _pcmio->n_playback_channels ()) {
 623                 _n_outputs = _pcmio->n_playback_channels ();
 624                 PBD::info << get_error_string(OutputChannelCountNotSupportedError) << endmsg;
 625         }
 626
 627         if (_n_inputs != _pcmio->n_capture_channels ()) {
 628                 _n_inputs = _pcmio->n_capture_channels ();
 629                 PBD::info << get_error_string(InputChannelCountNotSupportedError) << endmsg;
 630         }
 631 #if 0
 632         if (_pcmio->samples_per_period() != _samples_per_period) {
 633                 _samples_per_period = _pcmio->samples_per_period();
 634                 PBD::warning << _("PortAudioBackend: samples per period does not match.") << endmsg;
 635         }
 636 #endif
 637
 638         if (_pcmio->sample_rate() != _samplerate) {
 639                 _samplerate = _pcmio->sample_rate();
 640                 engine.sample_rate_change (_samplerate);
 641                 PBD::warning << get_error_string(SampleRateNotSupportedError) << endmsg;
 642         }
 643
 644         _measure_latency = for_latency_measurement;
 645
 646         _port_change_flag = false;
 647
 648         if (_midi_driver_option == winmme_driver_name) {
 649                 _midiio->set_enabled(true);
 650                 //_midiio->set_port_changed_callback(midi_port_change, this);
 651                 _midiio->start(); // triggers port discovery, callback coremidi_rediscover()
 652         }
 653
 654         _cycle_timer.set_samplerate(_samplerate);
 655         _cycle_timer.set_samples_per_cycle(_samples_per_period);
 656
 657         _dsp_calc.set_max_time_us (_cycle_timer.get_length_us());
 658
 659         DEBUG_MIDI ("Registering MIDI ports\n");
 660
 661         if (register_system_midi_ports () != 0) {
 662                 DEBUG_PORTS("Failed to register system midi ports.\n")
 663                 return PortRegistrationError;
 664         }
 665
 666         DEBUG_AUDIO ("Registering Audio ports\n");
 667
 668         if (register_system_audio_ports()) {
 669                 DEBUG_PORTS("Failed to register system audio ports.\n");
 670                 return PortRegistrationError;
 671         }
 672
 673         engine.sample_rate_change (_samplerate);
 674         engine.buffer_size_change (_samples_per_period);
 675
 676         if (engine.reestablish_ports ()) {
 677                 DEBUG_PORTS("Could not re-establish ports.\n");
 678                 return PortReconnectError;
 679         }
 680
 681         _run = true;
 682
 683         engine.reconnect_ports ();
 684         _port_change_flag = false;
 685
 686         if (_use_blocking_api) {
 687                 if (!start_blocking_process_thread()) {
 688                         return ProcessThreadStartError;
 689                 }
 690         } else {
 691                 if (_pcmio->start_stream() != paNoError) {
 692                         DEBUG_AUDIO("Unable to start stream\n");
 693                         return AudioDeviceOpenError;
 694                 }
 695
 696                 if (!start_freewheel_process_thread()) {
 697                         DEBUG_AUDIO("Unable to start freewheel thread\n");
 698                         stop();
 699                         return ProcessThreadStartError;
 700                 }
 701
 702                 /* wait for backend to become active */
 703                 int timeout = 5000;
 704                 while (!_active && --timeout > 0) { Glib::usleep (1000); }
 705
 706                 if (timeout == 0 || !_active) {
 707                         PBD::error << _("PortAudio:: failed to start device.") << endmsg;
 708                         stop ();
 709                         return ProcessThreadStartError;
 710                 }
 711         }
 712
 713         return NoError;
 714 }
 715
 716 int
 717 PortAudioBackend::portaudio_callback(const void* input,
 718                                      void* output,
 719                                      unsigned long frame_count,
 720                                      const PaStreamCallbackTimeInfo* time_info,
 721                                      PaStreamCallbackFlags status_flags,
 722                                      void* user_data)
 723 {
 724         PortAudioBackend* pa_backend = static_cast<PortAudioBackend*>(user_data);
 725
 726         if (!pa_backend->process_callback((const float*)input,
 727                                           (float*)output,
 728                                           frame_count,
 729                                           time_info,
 730                                           status_flags)) {
 731                 return paAbort;
 732         }
 733
 734         return paContinue;
 735 }
 736
 737 bool
 738 PortAudioBackend::process_callback(const float* input,
 739                                    float* output,
 740                                    uint32_t frame_count,
 741                                    const PaStreamCallbackTimeInfo* timeInfo,
 742                                    PaStreamCallbackFlags statusFlags)
 743 {
 744         _active = true;
 745
 746         _dsp_calc.set_start_timestamp_us (PBD::get_microseconds());
 747
 748         if (_run && _freewheel && !_freewheel_ack) {
 749                 // acknowledge freewheeling; hand-over thread ID
 750                 pthread_mutex_lock (&_freewheel_mutex);
 751                 if (_freewheel) {
 752                         DEBUG_AUDIO("Setting _freewheel_ack = true;\n");
 753                         _freewheel_ack = true;
 754                 }
 755                 DEBUG_AUDIO("Signalling freewheel thread\n");
 756                 pthread_cond_signal (&_freewheel_signal);
 757                 pthread_mutex_unlock (&_freewheel_mutex);
 758         }
 759
 760         if (statusFlags & paInputUnderflow ||
 761                 statusFlags & paInputOverflow ||
 762                 statusFlags & paOutputUnderflow ||
 763                 statusFlags & paOutputOverflow ) {
 764                 DEBUG_AUDIO("PortAudio: Xrun\n");
 765                 engine.Xrun();
 766                 return true;
 767         }
 768
 769         if (!_run || _freewheel) {
 770                 memset(output, 0, frame_count * sizeof(float) * _system_outputs.size());
 771                 return true;
 772         }
 773
 774         bool in_main_thread = pthread_equal(_main_thread, pthread_self());
 775
 776         if (_reinit_thread_callback || !in_main_thread) {
 777                 _reinit_thread_callback = false;
 778                 _main_thread = pthread_self();
 779                 AudioEngine::thread_init_callback (this);
 780         }
 781
 782         process_port_connection_changes();
 783
 784         return blocking_process_main (input, output);
 785 }
 786
 787 bool
 788 PortAudioBackend::start_blocking_process_thread ()
 789 {
 790         if (pbd_realtime_pthread_create (PBD_SCHED_FIFO, -20, 100000,
 791                                 &_main_blocking_thread, blocking_thread_func, this))
 792         {
 793                 if (pthread_create (&_main_blocking_thread, NULL, blocking_thread_func, this))
 794                 {
 795                         DEBUG_AUDIO("Failed to create main audio thread\n");
 796                         _run = false;
 797                         return false;
 798                 } else {
 799                         PBD::warning << get_error_string(AquireRealtimePermissionError) << endmsg;
 800                 }
 801         }
 802
 803         int timeout = 5000;
 804         while (!_active && --timeout > 0) { Glib::usleep (1000); }
 805
 806         if (timeout == 0 || !_active) {
 807                 DEBUG_AUDIO("Failed to start main audio thread\n");
 808                 _pcmio->close_stream();
 809                 _run = false;
 810                 unregister_ports();
 811                 _active = false;
 812                 return false;
 813         }
 814         return true;
 815 }
 816
 817 bool
 818 PortAudioBackend::stop_blocking_process_thread ()
 819 {
 820         void *status;
 821
 822         if (pthread_join (_main_blocking_thread, &status)) {
 823                 DEBUG_AUDIO("Failed to stop main audio thread\n");
 824                 return false;
 825         }
 826
 827         return true;
 828 }
 829
 830 int
 831 PortAudioBackend::stop ()
 832 {
 833         if (!_run) {
 834                 return 0;
 835         }
 836
 837         _midiio->stop();
 838
 839         _run = false;
 840
 841         if (_use_blocking_api) {
 842                 if (!stop_blocking_process_thread()) {
 843                         return -1;
 844                 }
 845         } else {
 846                 _pcmio->close_stream();
 847                 _active = false;
 848
 849                 if (!stop_freewheel_process_thread()) {
 850                         return -1;
 851                 }
 852         }
 853
 854         unregister_ports();
 855
 856         return (_active == false) ? 0 : -1;
 857 }
 858
 859 static void* freewheel_thread(void* arg)
 860 {
 861         PortAudioBackend* d = static_cast<PortAudioBackend*>(arg);
 862         d->freewheel_process_thread ();
 863         pthread_exit (0);
 864         return 0;
 865 }
 866
 867 bool
 868 PortAudioBackend::start_freewheel_process_thread ()
 869 {
 870         if (pthread_create(&_pthread_freewheel, NULL, freewheel_thread, this)) {
 871                 DEBUG_AUDIO("Failed to create main audio thread\n");
 872                 return false;
 873         }
 874
 875         int timeout = 5000;
 876         while (!_freewheel_thread_active && --timeout > 0) { Glib::usleep (1000); }
 877
 878         if (timeout == 0 || !_freewheel_thread_active) {
 879                 DEBUG_AUDIO("Failed to start freewheel thread\n");
 880                 return false;
 881         }
 882         return true;
 883 }
 884
 885 bool
 886 PortAudioBackend::stop_freewheel_process_thread ()
 887 {
 888         void *status;
 889
 890         if (!_freewheel_thread_active) {
 891                 return true;
 892         }
 893
 894         DEBUG_AUDIO("Signaling freewheel thread to stop\n");
 895
 896         pthread_mutex_lock (&_freewheel_mutex);
 897         pthread_cond_signal (&_freewheel_signal);
 898         pthread_mutex_unlock (&_freewheel_mutex);
 899
 900         if (pthread_join (_pthread_freewheel, &status) != 0) {
 901                 DEBUG_AUDIO("Failed to stop freewheel thread\n");
 902                 return false;
 903         }
 904
 905         return true;
 906 }
 907
 908 void*
 909 PortAudioBackend::freewheel_process_thread()
 910 {
 911         _freewheel_thread_active = true;
 912
 913         bool first_run = false;
 914
 915         pthread_mutex_lock (&_freewheel_mutex);
 916
 917         while(_run) {
 918                 // check if we should run,
 919                 if (_freewheeling != _freewheel) {
 920                         if (!_freewheeling) {
 921                                 DEBUG_AUDIO("Leaving freewheel\n");
 922                                 _freewheel = false; // first mark as disabled
 923                                 _reinit_thread_callback = true; // hand over _main_thread
 924                                 _freewheel_ack = false; // prepare next handshake
 925                                 _midiio->set_enabled(true);
 926                                 engine.freewheel_callback (_freewheeling);
 927                         } else {
 928                                 first_run = true;
 929                                 _freewheel = true;
 930                         }
 931                 }
 932
 933                 if (!_freewheel || !_freewheel_ack) {
 934                         // wait for a change, we use a timed wait to
 935                         // terminate early in case some error sets _run = 0
 936                         struct timeval tv;
 937                         struct timespec ts;
 938                         gettimeofday (&tv, NULL);
 939                         ts.tv_sec = tv.tv_sec + 3;
 940                         ts.tv_nsec = 0;
 941                         DEBUG_AUDIO("Waiting for freewheel change\n");
 942                         pthread_cond_timedwait (&_freewheel_signal, &_freewheel_mutex, &ts);
 943                         continue;
 944                 }
 945
 946                 if (first_run) {
 947                         // tell the engine we're ready to GO.
 948                         engine.freewheel_callback (_freewheeling);
 949                         first_run = false;
 950                         _main_thread = pthread_self();
 951                         AudioEngine::thread_init_callback (this);
 952                         _midiio->set_enabled(false);
 953                 }
 954
 955                 if (!blocking_process_freewheel()) {
 956                         break;
 957                 }
 958
 959                 process_port_connection_changes();
 960         }
 961
 962         pthread_mutex_unlock (&_freewheel_mutex);
 963
 964         _freewheel_thread_active = false;
 965
 966         if (_run) {
 967                 // engine.process_callback() returner error
 968                 engine.halted_callback("CoreAudio Freehweeling aborted.");
 969         }
 970         return 0;
 971 }
 972
 973 int
 974 PortAudioBackend::freewheel (bool onoff)
 975 {
 976         if (onoff == _freewheeling) {
 977                 return 0;
 978         }
 979         _freewheeling = onoff;
 980
 981         if (0 == pthread_mutex_trylock (&_freewheel_mutex)) {
 982                 pthread_cond_signal (&_freewheel_signal);
 983                 pthread_mutex_unlock (&_freewheel_mutex);
 984         }
 985         return 0;
 986 }
 987
 988 float
 989 PortAudioBackend::dsp_load () const
 990 {
 991         return 100.f * _dsp_load;
 992 }
 993
 994 size_t
 995 PortAudioBackend::raw_buffer_size (DataType t)
 996 {
 997         switch (t) {
 998         case DataType::AUDIO:
 999                 return _samples_per_period * sizeof(Sample);
1000         case DataType::MIDI:
1001                 return _max_buffer_size; // XXX not really limited
1002         }
1003         return 0;
1004 }
1005
1006 /* Process time */
1007 framepos_t
1008 PortAudioBackend::sample_time ()
1009 {
1010         return _processed_samples;
1011 }
1012
1013 framepos_t
1014 PortAudioBackend::sample_time_at_cycle_start ()
1015 {
1016         return _processed_samples;
1017 }
1018
1019 pframes_t
1020 PortAudioBackend::samples_since_cycle_start ()
1021 {
1022         if (!_active || !_run || _freewheeling || _freewheel) {
1023                 return 0;
1024         }
1025         if (!_cycle_timer.valid()) {
1026                 return 0;
1027         }
1028
1029         return _cycle_timer.samples_since_cycle_start (PBD::get_microseconds());
1030 }
1031
1032 int
1033 PortAudioBackend::name_to_id(std::string device_name) const {
1034         uint32_t device_id = UINT32_MAX;
1035         std::map<int, std::string> devices;
1036         _pcmio->input_device_list(devices);
1037         _pcmio->output_device_list(devices);
1038
1039         for (std::map<int, std::string>::const_iterator i = devices.begin (); i != devices.end(); ++i) {
1040                 if (i->second == device_name) {
1041                         device_id = i->first;
1042                         break;
1043                 }
1044         }
1045         return device_id;
1046 }
1047
1048 bool
1049 PortAudioBackend::set_mmcss_pro_audio (HANDLE* task_handle)
1050 {
1051         bool mmcss_success = PBD::MMCSS::set_thread_characteristics ("Pro Audio", task_handle);
1052
1053         if (!mmcss_success) {
1054                 PBD::warning << get_error_string(SettingAudioThreadPriorityError) << endmsg;
1055                 return false;
1056         } else {
1057                 DEBUG_THREADS("Thread characteristics set to Pro Audio\n");
1058         }
1059
1060         bool mmcss_priority =
1061                 PBD::MMCSS::set_thread_priority(*task_handle, PBD::MMCSS::AVRT_PRIORITY_NORMAL);
1062
1063         if (!mmcss_priority) {
1064                 PBD::warning << get_error_string(SettingAudioThreadPriorityError) << endmsg;
1065                 return false;
1066         } else {
1067                 DEBUG_THREADS("Thread priority set to AVRT_PRIORITY_NORMAL\n");
1068         }
1069
1070         return true;
1071 }
1072
1073 bool
1074 PortAudioBackend::reset_mmcss (HANDLE task_handle)
1075 {
1076         if (!PBD::MMCSS::revert_thread_characteristics(task_handle)) {
1077                 DEBUG_THREADS("Unable to reset process thread characteristics\n");
1078                 return false;
1079         }
1080         return true;
1081 }
1082
1083 void *
1084 PortAudioBackend::portaudio_process_thread (void *arg)
1085 {
1086         ThreadData* td = reinterpret_cast<ThreadData*> (arg);
1087         boost::function<void ()> f = td->f;
1088         delete td;
1089
1090 #ifdef USE_MMCSS_THREAD_PRIORITIES
1091         HANDLE task_handle;
1092         bool mmcss_success = set_mmcss_pro_audio (&task_handle);
1093 #endif
1094
1095         DWORD tid = GetCurrentThreadId ();
1096         DEBUG_THREADS (string_compose ("Process Thread Child ID: %1\n", tid));
1097
1098         f ();
1099
1100 #ifdef USE_MMCSS_THREAD_PRIORITIES
1101         if (mmcss_success) {
1102                 reset_mmcss (task_handle);
1103         }
1104 #endif
1105
1106         return 0;
1107 }
1108
1109 int
1110 PortAudioBackend::create_process_thread (boost::function<void()> func)
1111 {
1112         pthread_t thread_id;
1113         pthread_attr_t attr;
1114         size_t stacksize = 100000;
1115
1116         ThreadData* td = new ThreadData (this, func, stacksize);
1117
1118         if (pbd_realtime_pthread_create (PBD_SCHED_FIFO, -22, stacksize,
1119                                 &thread_id, portaudio_process_thread, td)) {
1120                 pthread_attr_init (&attr);
1121                 pthread_attr_setstacksize (&attr, stacksize);
1122                 if (pthread_create (&thread_id, &attr, portaudio_process_thread, td)) {
1123                         DEBUG_AUDIO("Cannot create process thread.");
1124                         pthread_attr_destroy (&attr);
1125                         return -1;
1126                 }
1127                 pthread_attr_destroy (&attr);
1128         }
1129
1130         _threads.push_back (thread_id);
1131         return 0;
1132 }
1133
1134 int
1135 PortAudioBackend::join_process_threads ()
1136 {
1137         int rv = 0;
1138
1139         for (std::vector<pthread_t>::const_iterator i = _threads.begin (); i != _threads.end (); ++i)
1140         {
1141                 void *status;
1142                 if (pthread_join (*i, &status)) {
1143                         DEBUG_AUDIO("Cannot terminate process thread.");
1144                         rv -= 1;
1145                 }
1146         }
1147         _threads.clear ();
1148         return rv;
1149 }
1150
1151 bool
1152 PortAudioBackend::in_process_thread ()
1153 {
1154         if (_use_blocking_api) {
1155                 if (pthread_equal(_main_blocking_thread, pthread_self()) != 0) {
1156                         return true;
1157                 }
1158         } else {
1159                 if (pthread_equal(_main_thread, pthread_self()) != 0) {
1160                         return true;
1161                 }
1162         }
1163         for (std::vector<pthread_t>::const_iterator i = _threads.begin (); i != _threads.end (); ++i)
1164         {
1165                 if (pthread_equal (*i, pthread_self ()) != 0) {
1166                         return true;
1167                 }
1168         }
1169         return false;
1170 }
1171
1172 uint32_t
1173 PortAudioBackend::process_thread_count ()
1174 {
1175         return _threads.size ();
1176 }
1177
1178 void
1179 PortAudioBackend::update_latencies ()
1180 {
1181         // trigger latency callback in RT thread (locked graph)
1182         port_connect_add_remove_callback();
1183 }
1184
1185 /* PORTENGINE API */
1186
1187 void*
1188 PortAudioBackend::private_handle () const
1189 {
1190         return NULL;
1191 }
1192
1193 const std::string&
1194 PortAudioBackend::my_name () const
1195 {
1196         return _instance_name;
1197 }
1198
1199 bool
1200 PortAudioBackend::available () const
1201 {
1202         return _run && _active;
1203 }
1204
1205 uint32_t
1206 PortAudioBackend::port_name_size () const
1207 {
1208         return 256;
1209 }
1210
1211 int
1212 PortAudioBackend::set_port_name (PortEngine::PortHandle port, const std::string& name)
1213 {
1214         if (!valid_port (port)) {
1215                 DEBUG_PORTS("set_port_name: Invalid Port(s)\n");
1216                 return -1;
1217         }
1218         return static_cast<PamPort*>(port)->set_name (_instance_name + ":" + name);
1219 }
1220
1221 std::string
1222 PortAudioBackend::get_port_name (PortEngine::PortHandle port) const
1223 {
1224         if (!valid_port (port)) {
1225                 DEBUG_PORTS("get_port_name: Invalid Port(s)\n");
1226                 return std::string ();
1227         }
1228         return static_cast<PamPort*>(port)->name ();
1229 }
1230
1231 int
1232 PortAudioBackend::get_port_property (PortHandle port,
1233                                      const std::string& key,
1234                                      std::string& value,
1235                                      std::string& type) const
1236 {
1237         if (!valid_port (port)) {
1238                 DEBUG_PORTS("get_port_name: Invalid Port(s)\n");
1239                 return -1;
1240         }
1241
1242         if (key == "http://jackaudio.org/metadata/pretty-name") {
1243                 type = "";
1244                 value = static_cast<PamPort*>(port)->pretty_name ();
1245                 if (!value.empty()) {
1246                         return 0;
1247                 }
1248         }
1249         return -1;
1250 }
1251
1252 int
1253 PortAudioBackend::set_port_property (PortHandle port,
1254                                      const std::string& key,
1255                                      const std::string& value,
1256                                      const std::string& type)
1257 {
1258         if (!valid_port (port)) {
1259                 DEBUG_PORTS("get_port_name: Invalid Port(s)\n");
1260                 return -1;
1261         }
1262
1263         if (key == "http://jackaudio.org/metadata/pretty-name" && type.empty ()) {
1264                 static_cast<PamPort*>(port)->set_pretty_name (value);
1265                 return 0;
1266         }
1267         return -1;
1268 }
1269
1270 PortEngine::PortHandle
1271 PortAudioBackend::get_port_by_name (const std::string& name) const
1272 {
1273         PortHandle port = (PortHandle) find_port (name);
1274         return port;
1275 }
1276
1277 int
1278 PortAudioBackend::get_ports (
1279                 const std::string& port_name_pattern,
1280                 DataType type, PortFlags flags,
1281                 std::vector<std::string>& port_names) const
1282 {
1283         int rv = 0;
1284         regex_t port_regex;
1285         bool use_regexp = false;
1286         if (port_name_pattern.size () > 0) {
1287                 if (!regcomp (&port_regex, port_name_pattern.c_str (), REG_EXTENDED|REG_NOSUB)) {
1288                         use_regexp = true;
1289                 }
1290         }
1291         for (size_t i = 0; i < _ports.size (); ++i) {
1292                 PamPort* port = _ports[i];
1293                 if ((port->type () == type) && flags == (port->flags () & flags)) {
1294                         if (!use_regexp || !regexec (&port_regex, port->name ().c_str (), 0, NULL, 0)) {
1295                                 port_names.push_back (port->name ());
1296                                 ++rv;
1297                         }
1298                 }
1299         }
1300         if (use_regexp) {
1301                 regfree (&port_regex);
1302         }
1303         return rv;
1304 }
1305
1306 DataType
1307 PortAudioBackend::port_data_type (PortEngine::PortHandle port) const
1308 {
1309         if (!valid_port (port)) {
1310                 return DataType::NIL;
1311         }
1312         return static_cast<PamPort*>(port)->type ();
1313 }
1314
1315 PortEngine::PortHandle
1316 PortAudioBackend::register_port (
1317                 const std::string& name,
1318                 ARDOUR::DataType type,
1319                 ARDOUR::PortFlags flags)
1320 {
1321         if (name.size () == 0) { return 0; }
1322         if (flags & IsPhysical) { return 0; }
1323         return add_port (_instance_name + ":" + name, type, flags);
1324 }
1325
1326 PortEngine::PortHandle
1327 PortAudioBackend::add_port (
1328                 const std::string& name,
1329                 ARDOUR::DataType type,
1330                 ARDOUR::PortFlags flags)
1331 {
1332         assert(name.size ());
1333         if (find_port (name)) {
1334                 DEBUG_PORTS(
1335                     string_compose("register_port: Port already exists: (%1)\n", name));
1336                 return 0;
1337         }
1338         PamPort* port = NULL;
1339         switch (type) {
1340         case DataType::AUDIO:
1341                 port = new PortAudioPort(*this, name, flags);
1342                 break;
1343         case DataType::MIDI:
1344                 port = new PortMidiPort(*this, name, flags);
1345                 break;
1346         default:
1347                 DEBUG_PORTS("register_port: Invalid Data Type.\n");
1348                 return 0;
1349         }
1350
1351         _ports.push_back (port);
1352
1353         return port;
1354 }
1355
1356 void
1357 PortAudioBackend::unregister_port (PortEngine::PortHandle port_handle)
1358 {
1359         if (!_run) {
1360                 return;
1361         }
1362         PamPort* port = static_cast<PamPort*>(port_handle);
1363         std::vector<PamPort*>::iterator i = std::find (_ports.begin (), _ports.end (), static_cast<PamPort*>(port_handle));
1364         if (i == _ports.end ()) {
1365                 DEBUG_PORTS("unregister_port: Failed to find port\n");
1366                 return;
1367         }
1368         disconnect_all(port_handle);
1369         _ports.erase (i);
1370         delete port;
1371 }
1372
1373 int
1374 PortAudioBackend::register_system_audio_ports()
1375 {
1376         LatencyRange lr;
1377
1378         const uint32_t a_ins = _n_inputs;
1379         const uint32_t a_out = _n_outputs;
1380
1381         uint32_t capture_latency = 0;
1382         uint32_t playback_latency = 0;
1383
1384         // guard against erroneous latency values
1385         if (_pcmio->capture_latency() > _samples_per_period) {
1386                 capture_latency = _pcmio->capture_latency() - _samples_per_period;
1387         }
1388         if (_pcmio->playback_latency() > _samples_per_period) {
1389                 playback_latency = _pcmio->playback_latency() - _samples_per_period;
1390         }
1391
1392         /* audio ports */
1393         lr.min = lr.max = capture_latency + (_measure_latency ? 0 : _systemic_audio_input_latency);
1394         for (uint32_t i = 0; i < a_ins; ++i) {
1395                 char tmp[64];
1396                 snprintf(tmp, sizeof(tmp), "system:capture_%d", i+1);
1397                 PortHandle p = add_port(std::string(tmp), DataType::AUDIO, static_cast<PortFlags>(IsOutput | IsPhysical | IsTerminal));
1398                 if (!p) return -1;
1399                 set_latency_range (p, false, lr);
1400                 PortAudioPort* audio_port = static_cast<PortAudioPort*>(p);
1401                 audio_port->set_pretty_name (
1402                     _pcmio->get_input_channel_name (name_to_id (_input_audio_device), i));
1403                 _system_inputs.push_back (audio_port);
1404         }
1405
1406         lr.min = lr.max = playback_latency + (_measure_latency ? 0 : _systemic_audio_output_latency);
1407         for (uint32_t i = 0; i < a_out; ++i) {
1408                 char tmp[64];
1409                 snprintf(tmp, sizeof(tmp), "system:playback_%d", i+1);
1410                 PortHandle p = add_port(std::string(tmp), DataType::AUDIO, static_cast<PortFlags>(IsInput | IsPhysical | IsTerminal));
1411                 if (!p) return -1;
1412                 set_latency_range (p, true, lr);
1413                 PortAudioPort* audio_port = static_cast<PortAudioPort*>(p);
1414                 audio_port->set_pretty_name (
1415                     _pcmio->get_output_channel_name (name_to_id (_output_audio_device), i));
1416                 _system_outputs.push_back(audio_port);
1417         }
1418         return 0;
1419 }
1420
1421 int
1422 PortAudioBackend::register_system_midi_ports()
1423 {
1424         if (_midi_driver_option == get_standard_device_name(DeviceNone)) {
1425                 DEBUG_MIDI("No MIDI backend selected, not system midi ports available\n");
1426                 return 0;
1427         }
1428
1429         LatencyRange lr;
1430         lr.min = lr.max = _samples_per_period;
1431
1432         const std::vector<WinMMEMidiInputDevice*> inputs = _midiio->get_inputs();
1433
1434         for (std::vector<WinMMEMidiInputDevice*>::const_iterator i = inputs.begin ();
1435              i != inputs.end ();
1436              ++i) {
1437                 std::string port_name = "system:midi_capture_" + (*i)->name();
1438                 PortHandle p =
1439                     add_port (port_name,
1440                               DataType::MIDI,
1441                               static_cast<PortFlags>(IsOutput | IsPhysical | IsTerminal));
1442                 if (!p) return -1;
1443
1444                 MidiDeviceInfo* info = _midiio->get_device_info((*i)->name());
1445                 if (info) { // assert?
1446                         lr.min = lr.max = _samples_per_period + info->systemic_input_latency;
1447                 }
1448                 set_latency_range (p, false, lr);
1449
1450                 PortMidiPort* midi_port = static_cast<PortMidiPort*>(p);
1451                 midi_port->set_pretty_name ((*i)->name());
1452                 _system_midi_in.push_back (midi_port);
1453                 DEBUG_MIDI (string_compose ("Registered MIDI input port: %1\n", port_name));
1454         }
1455
1456         const std::vector<WinMMEMidiOutputDevice*> outputs = _midiio->get_outputs();
1457
1458         for (std::vector<WinMMEMidiOutputDevice*>::const_iterator i = outputs.begin ();
1459              i != outputs.end ();
1460              ++i) {
1461                 std::string port_name = "system:midi_playback_" + (*i)->name();
1462                 PortHandle p =
1463                     add_port (port_name,
1464                               DataType::MIDI,
1465                               static_cast<PortFlags>(IsInput | IsPhysical | IsTerminal));
1466                 if (!p) return -1;
1467
1468                 MidiDeviceInfo* info = _midiio->get_device_info((*i)->name());
1469                 if (info) { // assert?
1470                         lr.min = lr.max = _samples_per_period + info->systemic_output_latency;
1471                 }
1472                 set_latency_range (p, false, lr);
1473
1474                 PortMidiPort* midi_port = static_cast<PortMidiPort*>(p);
1475                 midi_port->set_n_periods(2);
1476                 midi_port->set_pretty_name ((*i)->name());
1477                 _system_midi_out.push_back (midi_port);
1478                 DEBUG_MIDI (string_compose ("Registered MIDI output port: %1\n", port_name));
1479         }
1480         return 0;
1481 }
1482
1483 void
1484 PortAudioBackend::unregister_ports (bool system_only)
1485 {
1486         size_t i = 0;
1487         _system_inputs.clear();
1488         _system_outputs.clear();
1489         _system_midi_in.clear();
1490         _system_midi_out.clear();
1491         while (i <  _ports.size ()) {
1492                 PamPort* port = _ports[i];
1493                 if (! system_only || (port->is_physical () && port->is_terminal ())) {
1494                         port->disconnect_all ();
1495                         delete port;
1496                         _ports.erase (_ports.begin() + i);
1497                 } else {
1498                         ++i;
1499                 }
1500         }
1501 }
1502
1503 int
1504 PortAudioBackend::connect (const std::string& src, const std::string& dst)
1505 {
1506         PamPort* src_port = find_port (src);
1507         PamPort* dst_port = find_port (dst);
1508
1509         if (!src_port) {
1510                 DEBUG_PORTS(string_compose("connect: Invalid Source port: (%1)\n", src));
1511                 return -1;
1512         }
1513         if (!dst_port) {
1514                 DEBUG_PORTS(string_compose("connect: Invalid Destination port: (%1)\n", dst));
1515                 return -1;
1516         }
1517         return src_port->connect (dst_port);
1518 }
1519
1520 int
1521 PortAudioBackend::disconnect (const std::string& src, const std::string& dst)
1522 {
1523         PamPort* src_port = find_port (src);
1524         PamPort* dst_port = find_port (dst);
1525
1526         if (!src_port || !dst_port) {
1527                 DEBUG_PORTS("disconnect: Invalid Port(s)\n");
1528                 return -1;
1529         }
1530         return src_port->disconnect (dst_port);
1531 }
1532
1533 int
1534 PortAudioBackend::connect (PortEngine::PortHandle src, const std::string& dst)
1535 {
1536         PamPort* dst_port = find_port (dst);
1537         if (!valid_port (src)) {
1538                 DEBUG_PORTS("connect: Invalid Source Port Handle\n");
1539                 return -1;
1540         }
1541         if (!dst_port) {
1542                 DEBUG_PORTS(string_compose("connect: Invalid Destination Port (%1)\n", dst));
1543                 return -1;
1544         }
1545         return static_cast<PamPort*>(src)->connect (dst_port);
1546 }
1547
1548 int
1549 PortAudioBackend::disconnect (PortEngine::PortHandle src, const std::string& dst)
1550 {
1551         PamPort* dst_port = find_port (dst);
1552         if (!valid_port (src) || !dst_port) {
1553                 DEBUG_PORTS("disconnect: Invalid Port(s)\n");
1554                 return -1;
1555         }
1556         return static_cast<PamPort*>(src)->disconnect (dst_port);
1557 }
1558
1559 int
1560 PortAudioBackend::disconnect_all (PortEngine::PortHandle port)
1561 {
1562         if (!valid_port (port)) {
1563                 DEBUG_PORTS("disconnect_all: Invalid Port\n");
1564                 return -1;
1565         }
1566         static_cast<PamPort*>(port)->disconnect_all ();
1567         return 0;
1568 }
1569
1570 bool
1571 PortAudioBackend::connected (PortEngine::PortHandle port, bool /* process_callback_safe*/)
1572 {
1573         if (!valid_port (port)) {
1574                 DEBUG_PORTS("disconnect_all: Invalid Port\n");
1575                 return false;
1576         }
1577         return static_cast<PamPort*>(port)->is_connected ();
1578 }
1579
1580 bool
1581 PortAudioBackend::connected_to (PortEngine::PortHandle src, const std::string& dst, bool /*process_callback_safe*/)
1582 {
1583         PamPort* dst_port = find_port (dst);
1584         if (!valid_port (src) || !dst_port) {
1585                 DEBUG_PORTS("connected_to: Invalid Port\n");
1586                 return false;
1587         }
1588         return static_cast<PamPort*>(src)->is_connected (dst_port);
1589 }
1590
1591 bool
1592 PortAudioBackend::physically_connected (PortEngine::PortHandle port, bool /*process_callback_safe*/)
1593 {
1594         if (!valid_port (port)) {
1595                 DEBUG_PORTS("physically_connected: Invalid Port\n");
1596                 return false;
1597         }
1598         return static_cast<PamPort*>(port)->is_physically_connected ();
1599 }
1600
1601 int
1602 PortAudioBackend::get_connections (PortEngine::PortHandle port, std::vector<std::string>& names, bool /*process_callback_safe*/)
1603 {
1604         if (!valid_port (port)) {
1605                 DEBUG_PORTS("get_connections: Invalid Port\n");
1606                 return -1;
1607         }
1608
1609         assert (0 == names.size ());
1610
1611         const std::vector<PamPort*>& connected_ports = static_cast<PamPort*>(port)->get_connections ();
1612
1613         for (std::vector<PamPort*>::const_iterator i = connected_ports.begin (); i != connected_ports.end (); ++i) {
1614                 names.push_back ((*i)->name ());
1615         }
1616
1617         return (int)names.size ();
1618 }
1619
1620 /* MIDI */
1621 int
1622 PortAudioBackend::midi_event_get (
1623                 pframes_t& timestamp,
1624                 size_t& size, uint8_t const** buf, void* port_buffer,
1625                 uint32_t event_index)
1626 {
1627         if (!buf || !port_buffer) return -1;
1628         PortMidiBuffer& source = * static_cast<PortMidiBuffer*>(port_buffer);
1629         if (event_index >= source.size ()) {
1630                 return -1;
1631         }
1632         PortMidiEvent const& event = source[event_index];
1633
1634         timestamp = event.timestamp ();
1635         size = event.size ();
1636         *buf = event.data ();
1637         return 0;
1638 }
1639
1640 int
1641 PortAudioBackend::midi_event_put (
1642                 void* port_buffer,
1643                 pframes_t timestamp,
1644                 const uint8_t* buffer, size_t size)
1645 {
1646         if (!buffer || !port_buffer) return -1;
1647         PortMidiBuffer& dst = * static_cast<PortMidiBuffer*>(port_buffer);
1648 #ifndef NDEBUG
1649         if (dst.size () && (pframes_t)dst.back ().timestamp () > timestamp) {
1650                 // nevermind, ::get_buffer() sorts events
1651                 DEBUG_MIDI (string_compose ("PortMidiBuffer: unordered event: %1 > %2\n",
1652                                             (pframes_t)dst.back ().timestamp (),
1653                                             timestamp));
1654         }
1655 #endif
1656         dst.push_back (PortMidiEvent (timestamp, buffer, size));
1657         return 0;
1658 }
1659
1660 uint32_t
1661 PortAudioBackend::get_midi_event_count (void* port_buffer)
1662 {
1663         if (!port_buffer) return 0;
1664         return static_cast<PortMidiBuffer*>(port_buffer)->size ();
1665 }
1666
1667 void
1668 PortAudioBackend::midi_clear (void* port_buffer)
1669 {
1670         if (!port_buffer) return;
1671         PortMidiBuffer * buf = static_cast<PortMidiBuffer*>(port_buffer);
1672         assert (buf);
1673         buf->clear ();
1674 }
1675
1676 /* Monitoring */
1677
1678 bool
1679 PortAudioBackend::can_monitor_input () const
1680 {
1681         return false;
1682 }
1683
1684 int
1685 PortAudioBackend::request_input_monitoring (PortEngine::PortHandle, bool)
1686 {
1687         return -1;
1688 }
1689
1690 int
1691 PortAudioBackend::ensure_input_monitoring (PortEngine::PortHandle, bool)
1692 {
1693         return -1;
1694 }
1695
1696 bool
1697 PortAudioBackend::monitoring_input (PortEngine::PortHandle)
1698 {
1699         return false;
1700 }
1701
1702 /* Latency management */
1703
1704 void
1705 PortAudioBackend::set_latency_range (PortEngine::PortHandle port, bool for_playback, LatencyRange latency_range)
1706 {
1707         if (!valid_port (port)) {
1708                 DEBUG_PORTS("PamPort::set_latency_range (): invalid port.\n");
1709         }
1710         static_cast<PamPort*>(port)->set_latency_range (latency_range, for_playback);
1711 }
1712
1713 LatencyRange
1714 PortAudioBackend::get_latency_range (PortEngine::PortHandle port, bool for_playback)
1715 {
1716         LatencyRange r;
1717         if (!valid_port (port)) {
1718                 DEBUG_PORTS("PamPort::get_latency_range (): invalid port.\n");
1719                 r.min = 0;
1720                 r.max = 0;
1721                 return r;
1722         }
1723         PamPort* p = static_cast<PamPort*>(port);
1724         assert(p);
1725
1726         r = p->latency_range (for_playback);
1727         // TODO MIDI
1728         if (p->is_physical() && p->is_terminal() && p->type() == DataType::AUDIO) {
1729                 if (p->is_input() && for_playback) {
1730                         r.min += _samples_per_period;
1731                         r.max += _samples_per_period;
1732                 }
1733                 if (p->is_output() && !for_playback) {
1734                         r.min += _samples_per_period;
1735                         r.max += _samples_per_period;
1736                 }
1737         }
1738         return r;
1739 }
1740
1741 /* Discovering physical ports */
1742
1743 bool
1744 PortAudioBackend::port_is_physical (PortEngine::PortHandle port) const
1745 {
1746         if (!valid_port (port)) {
1747                 DEBUG_PORTS("PamPort::port_is_physical (): invalid port.\n");
1748                 return false;
1749         }
1750         return static_cast<PamPort*>(port)->is_physical ();
1751 }
1752
1753 void
1754 PortAudioBackend::get_physical_outputs (DataType type, std::vector<std::string>& port_names)
1755 {
1756         for (size_t i = 0; i < _ports.size (); ++i) {
1757                 PamPort* port = _ports[i];
1758                 if ((port->type () == type) && port->is_input () && port->is_physical ()) {
1759                         port_names.push_back (port->name ());
1760                 }
1761         }
1762 }
1763
1764 void
1765 PortAudioBackend::get_physical_inputs (DataType type, std::vector<std::string>& port_names)
1766 {
1767         for (size_t i = 0; i < _ports.size (); ++i) {
1768                 PamPort* port = _ports[i];
1769                 if ((port->type () == type) && port->is_output () && port->is_physical ()) {
1770                         port_names.push_back (port->name ());
1771                 }
1772         }
1773 }
1774
1775 ChanCount
1776 PortAudioBackend::n_physical_outputs () const
1777 {
1778         int n_midi = 0;
1779         int n_audio = 0;
1780         for (size_t i = 0; i < _ports.size (); ++i) {
1781                 PamPort* port = _ports[i];
1782                 if (port->is_output () && port->is_physical ()) {
1783                         switch (port->type ()) {
1784                         case DataType::AUDIO:
1785                                 ++n_audio;
1786                                 break;
1787                         case DataType::MIDI:
1788                                 ++n_midi;
1789                                 break;
1790                         default:
1791                                 break;
1792                         }
1793                 }
1794         }
1795         ChanCount cc;
1796         cc.set (DataType::AUDIO, n_audio);
1797         cc.set (DataType::MIDI, n_midi);
1798         return cc;
1799 }
1800
1801 ChanCount
1802 PortAudioBackend::n_physical_inputs () const
1803 {
1804         int n_midi = 0;
1805         int n_audio = 0;
1806         for (size_t i = 0; i < _ports.size (); ++i) {
1807                 PamPort* port = _ports[i];
1808                 if (port->is_input () && port->is_physical ()) {
1809                         switch (port->type ()) {
1810                         case DataType::AUDIO:
1811                                 ++n_audio;
1812                                 break;
1813                         case DataType::MIDI:
1814                                 ++n_midi;
1815                                 break;
1816                         default:
1817                                 break;
1818                         }
1819                 }
1820         }
1821         ChanCount cc;
1822         cc.set (DataType::AUDIO, n_audio);
1823         cc.set (DataType::MIDI, n_midi);
1824         return cc;
1825 }
1826
1827 /* Getting access to the data buffer for a port */
1828
1829 void*
1830 PortAudioBackend::get_buffer (PortEngine::PortHandle port, pframes_t nframes)
1831 {
1832         assert (port);
1833         assert (valid_port (port));
1834         if (!port || !valid_port (port)) return NULL; // XXX remove me
1835         return static_cast<PamPort*>(port)->get_buffer (nframes);
1836 }
1837
1838
1839 void *
1840 PortAudioBackend::blocking_process_thread ()
1841 {
1842         AudioEngine::thread_init_callback (this);
1843         _active = true;
1844         _processed_samples = 0;
1845
1846         manager.registration_callback();
1847         manager.graph_order_callback();
1848
1849         if (_pcmio->start_stream() != paNoError) {
1850                 _pcmio->close_stream ();
1851                 _active = false;
1852                 engine.halted_callback(get_error_string(AudioDeviceIOError).c_str());
1853         }
1854
1855 #ifdef USE_MMCSS_THREAD_PRIORITIES
1856         HANDLE task_handle;
1857         bool mmcss_success = set_mmcss_pro_audio (&task_handle);
1858 #endif
1859
1860         DWORD tid = GetCurrentThreadId ();
1861         DEBUG_THREADS (string_compose ("Process Thread Master ID: %1\n", tid));
1862
1863         while (_run) {
1864
1865                 if (_freewheeling != _freewheel) {
1866                         _freewheel = _freewheeling;
1867                         engine.freewheel_callback (_freewheel);
1868                 }
1869
1870                 if (!_freewheel) {
1871
1872                         switch (_pcmio->next_cycle (_samples_per_period)) {
1873                         case 0: // OK
1874                                 break;
1875                         case 1:
1876                                 DEBUG_AUDIO("PortAudio: Xrun\n");
1877                                 engine.Xrun();
1878                                 break;
1879                         default:
1880                                 PBD::error << get_error_string(AudioDeviceIOError) << endmsg;
1881                                 break;
1882                         }
1883
1884                         if (!blocking_process_main(_pcmio->get_capture_buffer(),
1885                                                    _pcmio->get_playback_buffer())) {
1886                                 return 0;
1887                         }
1888                 } else {
1889
1890                         if (!blocking_process_freewheel()) {
1891                                 return 0;
1892                         }
1893                 }
1894
1895                 process_port_connection_changes();
1896         }
1897         _pcmio->close_stream();
1898         _active = false;
1899         if (_run) {
1900                 engine.halted_callback(get_error_string(AudioDeviceIOError).c_str());
1901         }
1902
1903 #ifdef USE_MMCSS_THREAD_PRIORITIES
1904         if (mmcss_success) {
1905                 reset_mmcss(task_handle);
1906         }
1907 #endif
1908
1909         return 0;
1910 }
1911
1912 bool
1913 PortAudioBackend::blocking_process_main(const float* interleaved_input_data,
1914                                         float* interleaved_output_data)
1915 {
1916         uint32_t i = 0;
1917         int64_t min_elapsed_us = 1000000;
1918         int64_t max_elapsed_us = 0;
1919
1920         _dsp_calc.set_start_timestamp_us (PBD::get_microseconds());
1921
1922         i = 0;
1923         /* Copy input audio data into input port buffers */
1924         for (std::vector<PamPort*>::const_iterator it = _system_inputs.begin();
1925              it != _system_inputs.end();
1926              ++it, ++i) {
1927                 assert(_system_inputs.size() == _pcmio->n_capture_channels());
1928                 uint32_t channels = _system_inputs.size();
1929                 float* input_port_buffer = (float*)(*it)->get_buffer(_samples_per_period);
1930                 deinterleave_audio_data(
1931                     interleaved_input_data, input_port_buffer, _samples_per_period, i, channels);
1932         }
1933
1934         process_incoming_midi ();
1935
1936         /* clear output buffers */
1937         for (std::vector<PamPort*>::const_iterator it = _system_outputs.begin();
1938              it != _system_outputs.end();
1939              ++it) {
1940                 memset((*it)->get_buffer(_samples_per_period),
1941                        0,
1942                        _samples_per_period * sizeof(Sample));
1943         }
1944
1945         _last_cycle_start = _cycle_timer.get_start();
1946         _cycle_timer.reset_start(PBD::get_microseconds());
1947         _cycle_count++;
1948
1949         uint64_t cycle_diff_us = (_cycle_timer.get_start() - _last_cycle_start);
1950         int64_t deviation_us = (cycle_diff_us - _cycle_timer.get_length_us());
1951         _total_deviation_us += ::llabs(deviation_us);
1952         _max_deviation_us =
1953             std::max(_max_deviation_us, (uint64_t)::llabs(deviation_us));
1954
1955         if ((_cycle_count % 1000) == 0) {
1956                 uint64_t mean_deviation_us = _total_deviation_us / _cycle_count;
1957                 DEBUG_TIMING(string_compose("Mean avg cycle deviation: %1(ms), max %2(ms)\n",
1958                                             mean_deviation_us * 1e-3,
1959                                             _max_deviation_us * 1e-3));
1960         }
1961
1962         if (::llabs(deviation_us) > _cycle_timer.get_length_us()) {
1963                 DEBUG_TIMING(
1964                     string_compose("time between process(ms): %1, Est(ms): %2, Dev(ms): %3\n",
1965                                    cycle_diff_us * 1e-3,
1966                                    _cycle_timer.get_length_us() * 1e-3,
1967                                    deviation_us * 1e-3));
1968         }
1969
1970         /* call engine process callback */
1971         if (engine.process_callback(_samples_per_period)) {
1972                 _pcmio->close_stream();
1973                 _active = false;
1974                 return false;
1975         }
1976
1977         process_outgoing_midi ();
1978
1979         /* write back audio */
1980         i = 0;
1981         for (std::vector<PamPort*>::const_iterator it = _system_outputs.begin();
1982              it != _system_outputs.end();
1983              ++it, ++i) {
1984                 assert(_system_outputs.size() == _pcmio->n_playback_channels());
1985                 const uint32_t channels = _system_outputs.size();
1986                 float* output_port_buffer = (float*)(*it)->get_buffer(_samples_per_period);
1987                 interleave_audio_data(
1988                     output_port_buffer, interleaved_output_data, _samples_per_period, i, channels);
1989         }
1990
1991         _processed_samples += _samples_per_period;
1992
1993         /* calculate DSP load */
1994         _dsp_calc.set_stop_timestamp_us (PBD::get_microseconds());
1995         _dsp_load = _dsp_calc.get_dsp_load();
1996
1997         DEBUG_TIMING(string_compose("DSP Load: %1\n", _dsp_load));
1998
1999         max_elapsed_us = std::max(_dsp_calc.elapsed_time_us(), max_elapsed_us);
2000         min_elapsed_us = std::min(_dsp_calc.elapsed_time_us(), min_elapsed_us);
2001         if ((_cycle_count % 1000) == 0) {
2002                 DEBUG_TIMING(string_compose("Elapsed process time(usecs) max: %1, min: %2\n",
2003                                             max_elapsed_us,
2004                                             min_elapsed_us));
2005         }
2006
2007         return true;
2008 }
2009
2010 bool
2011 PortAudioBackend::blocking_process_freewheel()
2012 {
2013         // zero audio input buffers
2014         for (std::vector<PamPort*>::const_iterator it = _system_inputs.begin();
2015              it != _system_inputs.end();
2016              ++it) {
2017                 memset((*it)->get_buffer(_samples_per_period),
2018                        0,
2019                        _samples_per_period * sizeof(Sample));
2020         }
2021
2022         // TODO clear midi or stop midi recv when entering fwheelin'
2023
2024         if (engine.process_callback(_samples_per_period)) {
2025                 _pcmio->close_stream();
2026                 _active = false;
2027                 return false;
2028         }
2029
2030         // drop all outgoing MIDI messages
2031         for (std::vector<PamPort*>::const_iterator it = _system_midi_out.begin();
2032              it != _system_midi_out.end();
2033              ++it) {
2034                 void* bptr = (*it)->get_buffer(0);
2035                 midi_clear(bptr);
2036         }
2037
2038         _dsp_load = 1.0;
2039         Glib::usleep(100); // don't hog cpu
2040         return true;
2041 }
2042
2043 void
2044 PortAudioBackend::process_incoming_midi ()
2045 {
2046         uint32_t i = 0;
2047         for (std::vector<PamPort*>::const_iterator it = _system_midi_in.begin();
2048              it != _system_midi_in.end();
2049              ++it, ++i) {
2050                 PortMidiBuffer* mbuf = static_cast<PortMidiBuffer*>((*it)->get_buffer(0));
2051                 mbuf->clear();
2052                 uint64_t timestamp;
2053                 pframes_t sample_offset;
2054                 uint8_t data[MaxWinMidiEventSize];
2055                 size_t size = sizeof(data);
2056                 while (_midiio->dequeue_input_event(i,
2057                                                     _cycle_timer.get_start(),
2058                                                     _cycle_timer.get_next_start(),
2059                                                     timestamp,
2060                                                     data,
2061                                                     size)) {
2062                         sample_offset = _cycle_timer.samples_since_cycle_start(timestamp);
2063                         midi_event_put(mbuf, sample_offset, data, size);
2064                         DEBUG_MIDI(string_compose("Dequeuing incoming MIDI data for device: %1 "
2065                                                   "sample_offset: %2 timestamp: %3, size: %4\n",
2066                                                   _midiio->get_inputs()[i]->name(),
2067                                                   sample_offset,
2068                                                   timestamp,
2069                                                   size));
2070                         size = sizeof(data);
2071                 }
2072         }
2073 }
2074
2075 void
2076 PortAudioBackend::process_outgoing_midi ()
2077 {
2078         /* mixdown midi */
2079         for (std::vector<PamPort*>::iterator it = _system_midi_out.begin();
2080              it != _system_midi_out.end();
2081              ++it) {
2082                 static_cast<PortMidiPort*>(*it)->next_period();
2083         }
2084         /* queue outgoing midi */
2085         uint32_t i = 0;
2086         for (std::vector<PamPort*>::const_iterator it = _system_midi_out.begin();
2087              it != _system_midi_out.end();
2088              ++it, ++i) {
2089                 const PortMidiBuffer* src =
2090                     static_cast<const PortMidiPort*>(*it)->const_buffer();
2091
2092                 for (PortMidiBuffer::const_iterator mit = src->begin(); mit != src->end();
2093                      ++mit) {
2094                         uint64_t timestamp =
2095                             _cycle_timer.timestamp_from_sample_offset(mit->timestamp());
2096                         DEBUG_MIDI(string_compose("Queuing outgoing MIDI data for device: "
2097                                                   "%1 sample_offset: %2 timestamp: %3, size: %4\n",
2098                                                   _midiio->get_outputs()[i]->name(),
2099                                                   mit->timestamp(),
2100                                                   timestamp,
2101                                                   mit->size()));
2102                         _midiio->enqueue_output_event(i, timestamp, mit->data(), mit->size());
2103                 }
2104         }
2105 }
2106
2107 void
2108 PortAudioBackend::process_port_connection_changes ()
2109 {
2110         bool connections_changed = false;
2111         bool ports_changed = false;
2112         if (!pthread_mutex_trylock (&_port_callback_mutex)) {
2113                 if (_port_change_flag) {
2114                         ports_changed = true;
2115                         _port_change_flag = false;
2116                 }
2117                 if (!_port_connection_queue.empty ()) {
2118                         connections_changed = true;
2119                 }
2120                 while (!_port_connection_queue.empty ()) {
2121                         PortConnectData *c = _port_connection_queue.back ();
2122                         manager.connect_callback (c->a, c->b, c->c);
2123                         _port_connection_queue.pop_back ();
2124                         delete c;
2125                 }
2126                 pthread_mutex_unlock (&_port_callback_mutex);
2127         }
2128         if (ports_changed) {
2129                 manager.registration_callback();
2130         }
2131         if (connections_changed) {
2132                 manager.graph_order_callback();
2133         }
2134         if (connections_changed || ports_changed) {
2135                 engine.latency_callback(false);
2136                 engine.latency_callback(true);
2137         }
2138 }
2139
2140 /******************************************************************************/
2141
2142 static boost::shared_ptr<PortAudioBackend> _instance;
2143
2144 static boost::shared_ptr<AudioBackend> backend_factory (AudioEngine& e);
2145 static int instantiate (const std::string& arg1, const std::string& /* arg2 */);
2146 static int deinstantiate ();
2147 static bool already_configured ();
2148 static bool available ();
2149
2150 static ARDOUR::AudioBackendInfo _descriptor = {
2151         BACKEND_NAME,
2152         instantiate,
2153         deinstantiate,
2154         backend_factory,
2155         already_configured,
2156         available
2157 };
2158
2159 static boost::shared_ptr<AudioBackend>
2160 backend_factory (AudioEngine& e)
2161 {
2162         if (!_instance) {
2163                 _instance.reset (new PortAudioBackend (e, _descriptor));
2164         }
2165         return _instance;
2166 }
2167
2168 static int
2169 instantiate (const std::string& arg1, const std::string& /* arg2 */)
2170 {
2171         s_instance_name = arg1;
2172         return 0;
2173 }
2174
2175 static int
2176 deinstantiate ()
2177 {
2178         _instance.reset ();
2179         return 0;
2180 }
2181
2182 static bool
2183 already_configured ()
2184 {
2185         return false;
2186 }
2187
2188 static bool
2189 available ()
2190 {
2191         return true;
2192 }
2193
2194 extern "C" ARDOURBACKEND_API ARDOUR::AudioBackendInfo* descriptor ()
2195 {
2196         return &_descriptor;
2197 }
2198
2199
2200 /******************************************************************************/
2201 PamPort::PamPort (PortAudioBackend &b, const std::string& name, PortFlags flags)
2202         : _osx_backend (b)
2203         , _name  (name)
2204         , _flags (flags)
2205 {
2206         _capture_latency_range.min = 0;
2207         _capture_latency_range.max = 0;
2208         _playback_latency_range.min = 0;
2209         _playback_latency_range.max = 0;
2210 }
2211
2212 PamPort::~PamPort () {
2213         disconnect_all ();
2214 }
2215
2216
2217 int PamPort::connect (PamPort *port)
2218 {
2219         if (!port) {
2220                 DEBUG_PORTS("PamPort::connect (): invalid (null) port\n");
2221                 return -1;
2222         }
2223
2224         if (type () != port->type ()) {
2225                 DEBUG_PORTS("PamPort::connect (): wrong port-type\n");
2226                 return -1;
2227         }
2228
2229         if (is_output () && port->is_output ()) {
2230                 DEBUG_PORTS("PamPort::connect (): cannot inter-connect output ports.\n");
2231                 return -1;
2232         }
2233
2234         if (is_input () && port->is_input ()) {
2235                 DEBUG_PORTS("PamPort::connect (): cannot inter-connect input ports.\n");
2236                 return -1;
2237         }
2238
2239         if (this == port) {
2240                 DEBUG_PORTS("PamPort::connect (): cannot self-connect ports.\n");
2241                 return -1;
2242         }
2243
2244         if (is_connected (port)) {
2245 #if 0 // don't bother to warn about this for now. just ignore it
2246                 PBD::error << _("PamPort::connect (): ports are already connected:")
2247                         << " (" << name () << ") -> (" << port->name () << ")"
2248                         << endmsg;
2249 #endif
2250                 return -1;
2251         }
2252
2253         _connect (port, true);
2254         return 0;
2255 }
2256
2257
2258 void PamPort::_connect (PamPort *port, bool callback)
2259 {
2260         _connections.push_back (port);
2261         if (callback) {
2262                 port->_connect (this, false);
2263                 _osx_backend.port_connect_callback (name(),  port->name(), true);
2264         }
2265 }
2266
2267 int PamPort::disconnect (PamPort *port)
2268 {
2269         if (!port) {
2270                 DEBUG_PORTS("PamPort::disconnect (): invalid (null) port\n");
2271                 return -1;
2272         }
2273
2274         if (!is_connected (port)) {
2275                 DEBUG_PORTS(string_compose(
2276                     "PamPort::disconnect (): ports are not connected: (%1) -> (%2)\n",
2277                     name(),
2278                     port->name()));
2279                 return -1;
2280         }
2281         _disconnect (port, true);
2282         return 0;
2283 }
2284
2285 void PamPort::_disconnect (PamPort *port, bool callback)
2286 {
2287         std::vector<PamPort*>::iterator it = std::find (_connections.begin (), _connections.end (), port);
2288
2289         assert (it != _connections.end ());
2290
2291         _connections.erase (it);
2292
2293         if (callback) {
2294                 port->_disconnect (this, false);
2295                 _osx_backend.port_connect_callback (name(),  port->name(), false);
2296         }
2297 }
2298
2299
2300 void PamPort::disconnect_all ()
2301 {
2302         while (!_connections.empty ()) {
2303                 _connections.back ()->_disconnect (this, false);
2304                 _osx_backend.port_connect_callback (name(),  _connections.back ()->name(), false);
2305                 _connections.pop_back ();
2306         }
2307 }
2308
2309 bool
2310 PamPort::is_connected (const PamPort *port) const
2311 {
2312         return std::find (_connections.begin (), _connections.end (), port) != _connections.end ();
2313 }
2314
2315 bool PamPort::is_physically_connected () const
2316 {
2317         for (std::vector<PamPort*>::const_iterator it = _connections.begin (); it != _connections.end (); ++it) {
2318                 if ((*it)->is_physical ()) {
2319                         return true;
2320                 }
2321         }
2322         return false;
2323 }
2324
2325 /******************************************************************************/
2326
2327 PortAudioPort::PortAudioPort (PortAudioBackend &b, const std::string& name, PortFlags flags)
2328         : PamPort (b, name, flags)
2329 {
2330         memset (_buffer, 0, sizeof (_buffer));
2331 #ifndef PLATFORM_WINDOWS
2332         mlock(_buffer, sizeof (_buffer));
2333 #endif
2334 }
2335
2336 PortAudioPort::~PortAudioPort () { }
2337
2338 void* PortAudioPort::get_buffer (pframes_t n_samples)
2339 {
2340         if (is_input ()) {
2341                 std::vector<PamPort*>::const_iterator it = get_connections ().begin ();
2342                 if (it == get_connections ().end ()) {
2343                         memset (_buffer, 0, n_samples * sizeof (Sample));
2344                 } else {
2345                         PortAudioPort const * source = static_cast<const PortAudioPort*>(*it);
2346                         assert (source && source->is_output ());
2347                         memcpy (_buffer, source->const_buffer (), n_samples * sizeof (Sample));
2348                         while (++it != get_connections ().end ()) {
2349                                 source = static_cast<const PortAudioPort*>(*it);
2350                                 assert (source && source->is_output ());
2351                                 Sample* dst = buffer ();
2352                                 const Sample* src = source->const_buffer ();
2353                                 for (uint32_t s = 0; s < n_samples; ++s, ++dst, ++src) {
2354                                         *dst += *src;
2355                                 }
2356                         }
2357                 }
2358         }
2359         return _buffer;
2360 }
2361
2362
2363 PortMidiPort::PortMidiPort (PortAudioBackend &b, const std::string& name, PortFlags flags)
2364         : PamPort (b, name, flags)
2365         , _n_periods (1)
2366         , _bufperiod (0)
2367 {
2368         _buffer[0].clear ();
2369         _buffer[1].clear ();
2370
2371         _buffer[0].reserve (256);
2372         _buffer[1].reserve (256);
2373 }
2374
2375 PortMidiPort::~PortMidiPort () { }
2376
2377 struct MidiEventSorter {
2378         bool operator() (PortMidiEvent const& a, PortMidiEvent const& b) {
2379                 return a < b;
2380         }
2381 };
2382
2383 void* PortMidiPort::get_buffer (pframes_t /* nframes */)
2384 {
2385         if (is_input ()) {
2386                 (_buffer[_bufperiod]).clear ();
2387                 for (std::vector<PamPort*>::const_iterator i = get_connections ().begin ();
2388                                 i != get_connections ().end ();
2389                                 ++i) {
2390                         const PortMidiBuffer * src = static_cast<const PortMidiPort*>(*i)->const_buffer ();
2391                         for (PortMidiBuffer::const_iterator it = src->begin (); it != src->end (); ++it) {
2392                                 (_buffer[_bufperiod]).push_back (*it);
2393                         }
2394                 }
2395                 std::stable_sort ((_buffer[_bufperiod]).begin (), (_buffer[_bufperiod]).end (), MidiEventSorter());
2396         }
2397         return &(_buffer[_bufperiod]);
2398 }
2399
2400 PortMidiEvent::PortMidiEvent (const pframes_t timestamp, const uint8_t* data, size_t size)
2401         : _size (size)
2402         , _timestamp (timestamp)
2403 {
2404         if (size > 0 && size < MaxWinMidiEventSize) {
2405                 memcpy (_data, data, size);
2406         }
2407 }
2408
2409 PortMidiEvent::PortMidiEvent (const PortMidiEvent& other)
2410         : _size (other.size ())
2411         , _timestamp (other.timestamp ())
2412 {
2413         if (other._size > 0) {
2414                 assert (other._size < MaxWinMidiEventSize);
2415                 memcpy (_data, other._data, other._size);
2416         }
2417 };