do not allow smf_source's reads to stomp on cached read_end position in parent class...
[ardour.git] / libs / ardour / midi_diskstream.cc
1 /*
2     Copyright (C) 2000-2003 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 #include <fstream>
20 #include <cstdio>
21 #include <unistd.h>
22 #include <cmath>
23 #include <cerrno>
24 #include <string>
25 #include <climits>
26 #include <fcntl.h>
27 #include <cstdlib>
28 #include <ctime>
29 #include <sys/stat.h>
30 #include <sys/mman.h>
31
32 #include "pbd/error.h"
33 #include "pbd/basename.h"
34 #include <glibmm/thread.h>
35 #include "pbd/xml++.h"
36 #include "pbd/memento_command.h"
37 #include "pbd/enumwriter.h"
38
39 #include "ardour/ardour.h"
40 #include "ardour/audioengine.h"
41 #include "ardour/configuration.h"
42 #include "ardour/cycle_timer.h"
43 #include "ardour/io.h"
44 #include "ardour/midi_diskstream.h"
45 #include "ardour/midi_playlist.h"
46 #include "ardour/midi_port.h"
47 #include "ardour/midi_region.h"
48 #include "ardour/playlist_factory.h"
49 #include "ardour/region_factory.h"
50 #include "ardour/send.h"
51 #include "ardour/session.h"
52 #include "ardour/smf_source.h"
53 #include "ardour/utils.h"
54
55 #include "midi++/types.h"
56
57 #include "i18n.h"
58 #include <locale.h>
59
60 using namespace std;
61 using namespace ARDOUR;
62 using namespace PBD;
63
64 nframes_t MidiDiskstream::midi_readahead = 4096;
65
66 MidiDiskstream::MidiDiskstream (Session &sess, const string &name, Diskstream::Flag flag)
67         : Diskstream(sess, name, flag)
68         , _playback_buf(0)
69         , _capture_buf(0)
70         , _source_port(0)
71         , _last_flush_frame(0)
72         , _note_mode(Sustained)
73         , _frames_written_to_ringbuffer(0)
74         , _frames_read_from_ringbuffer(0)
75 {
76         /* prevent any write sources from being created */
77
78         in_set_state = true;
79
80         init(flag);
81         use_new_playlist ();
82
83         in_set_state = false;
84
85         assert(!destructive());
86 }
87         
88 MidiDiskstream::MidiDiskstream (Session& sess, const XMLNode& node)
89         : Diskstream(sess, node)
90         , _playback_buf(0)
91         , _capture_buf(0)
92         , _source_port(0)
93         , _last_flush_frame(0)
94         , _note_mode(Sustained)
95         , _frames_written_to_ringbuffer(0)
96         , _frames_read_from_ringbuffer(0)
97 {
98         in_set_state = true;
99         init (Recordable);
100
101         if (set_state (node)) {
102                 in_set_state = false;
103                 throw failed_constructor();
104         }
105
106         in_set_state = false;
107
108         if (destructive()) {
109                 use_destructive_playlist ();
110         }
111 }
112
113 void
114 MidiDiskstream::init (Diskstream::Flag f)
115 {
116         Diskstream::init(f);
117
118         /* there are no channels at this point, so these
119            two calls just get speed_buffer_size and wrap_buffer
120            size setup without duplicating their code.
121         */
122
123         set_block_size (_session.get_block_size());
124         allocate_temporary_buffers ();
125
126         const size_t size = _session.midi_diskstream_buffer_size();
127         _playback_buf = new MidiRingBuffer<nframes_t>(size);
128         _capture_buf = new MidiRingBuffer<nframes_t>(size);
129         
130         _n_channels = ChanCount(DataType::MIDI, 1);
131
132         assert(recordable());
133 }
134
135 MidiDiskstream::~MidiDiskstream ()
136 {
137         Glib::Mutex::Lock lm (state_lock);
138 }
139
140         
141 void
142 MidiDiskstream::non_realtime_locate (nframes_t position)
143 {
144         if (_write_source) {
145                 _write_source->set_timeline_position (position);
146         }
147         seek(position, false);
148 }
149
150
151 void
152 MidiDiskstream::non_realtime_input_change ()
153 {
154         { 
155                 Glib::Mutex::Lock lm (state_lock);
156
157                 if (input_change_pending == NoChange) {
158                         return;
159                 }
160
161                 if (input_change_pending & ConfigurationChanged) {
162                         if (_io->n_ports().n_midi() != _n_channels.n_midi()) {
163                                 error << "Can not feed IO " << _io->n_ports()
164                                         << " with diskstream " << _n_channels << endl;
165                         }
166                 } 
167
168                 get_input_sources ();
169                 set_capture_offset ();
170
171                 if (first_input_change) {
172                         set_align_style (_persistent_alignment_style);
173                         first_input_change = false;
174                 } else {
175                         set_align_style_from_io ();
176                 }
177
178                 input_change_pending = NoChange;
179                 
180                 /* implicit unlock */
181         }
182
183         /* reset capture files */
184
185         reset_write_sources (false);
186
187         /* now refill channel buffers */
188
189         if (speed() != 1.0f || speed() != -1.0f) {
190                 seek ((nframes_t) (_session.transport_frame() * (double) speed()));
191         }
192         else {
193                 seek (_session.transport_frame());
194         }
195
196         _last_flush_frame = _session.transport_frame();
197 }
198
199 void
200 MidiDiskstream::get_input_sources ()
201 {
202         uint32_t ni = _io->n_ports().n_midi();
203
204         if (ni == 0) {
205                 return;
206         }
207
208         // This is all we do for now at least
209         assert(ni == 1);
210
211         _source_port = _io->midi(0);
212
213         // do... stuff?
214 }               
215
216 int
217 MidiDiskstream::find_and_use_playlist (const string& name)
218 {
219         boost::shared_ptr<MidiPlaylist> playlist;
220                 
221         if ((playlist = boost::dynamic_pointer_cast<MidiPlaylist> (_session.playlist_by_name (name))) == 0) {
222                 playlist = boost::dynamic_pointer_cast<MidiPlaylist> (PlaylistFactory::create (DataType::MIDI, _session, name));
223         }
224
225         if (!playlist) {
226                 error << string_compose(_("MidiDiskstream: Playlist \"%1\" isn't an midi playlist"), name) << endmsg;
227                 return -1;
228         }
229
230         return use_playlist (playlist);
231 }
232
233 int
234 MidiDiskstream::use_playlist (boost::shared_ptr<Playlist> playlist)
235 {       
236         assert(boost::dynamic_pointer_cast<MidiPlaylist>(playlist));
237
238         Diskstream::use_playlist(playlist);
239
240         return 0;
241 }
242
243 int
244 MidiDiskstream::use_new_playlist ()
245 {       
246         string newname;
247         boost::shared_ptr<MidiPlaylist> playlist;
248
249         if (!in_set_state && destructive()) {
250                 return 0;
251         }
252
253         if (_playlist) {
254                 newname = Playlist::bump_name (_playlist->name(), _session);
255         } else {
256                 newname = Playlist::bump_name (_name, _session);
257         }
258
259         if ((playlist = boost::dynamic_pointer_cast<MidiPlaylist> (PlaylistFactory::create (
260                         DataType::MIDI, _session, newname, hidden()))) != 0) {
261                 
262                 playlist->set_orig_diskstream_id (id());
263                 return use_playlist (playlist);
264
265         } else { 
266                 return -1;
267         }
268 }
269
270 int
271 MidiDiskstream::use_copy_playlist ()
272 {
273         assert(midi_playlist());
274
275         if (destructive()) {
276                 return 0;
277         }
278
279         if (_playlist == 0) {
280                 error << string_compose(_("MidiDiskstream %1: there is no existing playlist to make a copy of!"), _name) << endmsg;
281                 return -1;
282         }
283
284         string newname;
285         boost::shared_ptr<MidiPlaylist> playlist;
286
287         newname = Playlist::bump_name (_playlist->name(), _session);
288         
289         if ((playlist  = boost::dynamic_pointer_cast<MidiPlaylist>(PlaylistFactory::create (midi_playlist(), newname))) != 0) {
290                 playlist->set_orig_diskstream_id (id());
291                 return use_playlist (playlist);
292         } else { 
293                 return -1;
294         }
295 }
296
297 /** Overloaded from parent to die horribly
298  */
299 int
300 MidiDiskstream::set_destructive (bool yn)
301 {
302         assert( ! destructive());
303         assert( ! yn);
304         return -1;
305 }
306         
307 void
308 MidiDiskstream::set_note_mode (NoteMode m)
309 {
310         _note_mode = m;
311         midi_playlist()->set_note_mode(m);
312         if (_write_source && _write_source->model())
313                 _write_source->model()->set_note_mode(m);
314 }
315
316 void
317 MidiDiskstream::check_record_status (nframes_t transport_frame, nframes_t /*nframes*/, bool can_record)
318 {
319         // FIXME: waaay too much code to duplicate (AudioDiskstream)
320         
321         int possibly_recording;
322         int rolling;
323         int change;
324         const int transport_rolling = 0x4;
325         const int track_rec_enabled = 0x2;
326         const int global_rec_enabled = 0x1;
327
328         /* merge together the 3 factors that affect record status, and compute
329            what has changed.
330         */
331
332         rolling = _session.transport_speed() != 0.0f;
333         possibly_recording = (rolling << 2) | (record_enabled() << 1) | can_record;
334         change = possibly_recording ^ last_possibly_recording;
335
336         if (possibly_recording == last_possibly_recording) {
337                 return;
338         }
339
340         /* change state */
341
342         /* if per-track or global rec-enable turned on while the other was already on, we've started recording */
343
344         if (((change & track_rec_enabled) && record_enabled() && (!(change & global_rec_enabled) && can_record)) || 
345             ((change & global_rec_enabled) && can_record && (!(change & track_rec_enabled) && record_enabled()))) {
346                 
347                 /* starting to record: compute first+last frames */
348
349                 first_recordable_frame = transport_frame + _capture_offset;
350                 last_recordable_frame = max_frames;
351                 capture_start_frame = transport_frame;
352
353                 if (!(last_possibly_recording & transport_rolling) && (possibly_recording & transport_rolling)) {
354
355                         /* was stopped, now rolling (and recording) */
356
357                         if (_alignment_style == ExistingMaterial) {
358                                 first_recordable_frame += _session.worst_output_latency();
359                         } else {
360                                 first_recordable_frame += _roll_delay;
361                         }
362                 
363                 } else {
364
365                         /* was rolling, but record state changed */
366
367                         if (_alignment_style == ExistingMaterial) {
368
369
370                                 if (!_session.config.get_punch_in()) {
371
372                                         /* manual punch in happens at the correct transport frame
373                                            because the user hit a button. but to get alignment correct 
374                                            we have to back up the position of the new region to the 
375                                            appropriate spot given the roll delay.
376                                         */
377
378                                         capture_start_frame -= _roll_delay;
379
380                                         /* XXX paul notes (august 2005): i don't know why
381                                            this is needed.
382                                         */
383
384                                         first_recordable_frame += _capture_offset;
385
386                                 } else {
387
388                                         /* autopunch toggles recording at the precise
389                                            transport frame, and then the DS waits
390                                            to start recording for a time that depends
391                                            on the output latency.
392                                         */
393
394                                         first_recordable_frame += _session.worst_output_latency();
395                                 }
396
397                         } else {
398
399                                 if (_session.config.get_punch_in()) {
400                                         first_recordable_frame += _roll_delay;
401                                 } else {
402                                         capture_start_frame -= _roll_delay;
403                                 }
404                         }
405                         
406                 }
407
408         } else if (!record_enabled() || !can_record) {
409                 
410                 /* stop recording */
411
412                 last_recordable_frame = transport_frame + _capture_offset;
413                 
414                 if (_alignment_style == ExistingMaterial) {
415                         last_recordable_frame += _session.worst_output_latency();
416                 } else {
417                         last_recordable_frame += _roll_delay;
418                 }
419         }
420
421         last_possibly_recording = possibly_recording;
422 }
423
424 #if 0
425 static void
426 trace_midi (ostream& o, MIDI::byte *msg, size_t len)
427 {
428         using namespace MIDI;
429         eventType type;
430         const char trace_prefix = ':';
431         
432         type = (eventType) (msg[0]&0xF0);
433
434         switch (type) {
435         case off:
436                 o << trace_prefix
437                    << "Channel "
438                    << (msg[0]&0xF)+1
439                    << " NoteOff NoteNum "
440                    << (int) msg[1]
441                    << " Vel "
442                    << (int) msg[2]
443                    << endl;
444                 break;
445                 
446         case on:
447                 o << trace_prefix
448                    << "Channel "
449                    << (msg[0]&0xF)+1
450                    << " NoteOn NoteNum "
451                    << (int) msg[1]
452                    << " Vel "
453                    << (int) msg[2]
454                    << endl;
455                 break;
456             
457         case polypress:
458                 o << trace_prefix
459                    << "Channel "
460                    << (msg[0]&0xF)+1
461                    << " PolyPressure"
462                    << (int) msg[1]
463                    << endl;
464                 break;
465             
466         case MIDI::controller:
467                 o << trace_prefix
468                    << "Channel "
469                    << (msg[0]&0xF)+1
470                    << " Controller "
471                    << (int) msg[1]
472                    << " Value "
473                    << (int) msg[2]
474                    << endl;
475                 break;
476                 
477         case program:
478                 o << trace_prefix 
479                    << "Channel "
480                    << (msg[0]&0xF)+1
481                    <<  " Program Change ProgNum "
482                    << (int) msg[1]
483                    << endl;
484                 break;
485                 
486         case chanpress:
487                 o << trace_prefix 
488                    << "Channel "
489                    << (msg[0]&0xF)+1
490                    << " Channel Pressure "
491                    << (int) msg[1]
492                    << endl;
493                 break;
494             
495         case MIDI::pitchbend:
496                 o << trace_prefix
497                    << "Channel "
498                    << (msg[0]&0xF)+1
499                    << " Pitch Bend "
500                    << ((msg[2]<<7)|msg[1])
501                    << endl;
502                 break;
503             
504         case MIDI::sysex:
505                 if (len == 1) {
506                         switch (msg[0]) {
507                         case 0xf8:
508                                 o << trace_prefix
509                                    << "Clock"
510                                    << endl;
511                                 break;
512                         case 0xfa:
513                                 o << trace_prefix
514                                    << "Start"
515                                    << endl;
516                                 break;
517                         case 0xfb:
518                                 o << trace_prefix
519                                    << "Continue"
520                                    << endl;
521                                 break;
522                         case 0xfc:
523                                 o << trace_prefix
524                                    << "Stop"
525                                    << endl;
526                                 break;
527                         case 0xfe:
528                                 o << trace_prefix
529                                    << "Active Sense"
530                                    << endl;
531                                 break;
532                         case 0xff:
533                                 o << trace_prefix
534                                    << "System Reset"
535                                    << endl;
536                                 break;
537                         default:
538                                 o << trace_prefix
539                                    << "System Exclusive (1 byte : " << hex << (int) *msg << dec << ')'
540                                    << endl;             
541                                 break;
542                         } 
543                 } else {
544                         o << trace_prefix
545                            << "System Exclusive (" << len << ") = [ " << hex;
546                         for (unsigned int i = 0; i < len; ++i) {
547                                 o << (int) msg[i] << ' ';
548                         }
549                         o << dec << ']' << endl;
550                         
551                 }
552                 break;
553             
554         case MIDI::song:
555                 o << trace_prefix << "Song" << endl;
556                 break;
557             
558         case MIDI::tune:
559                 o << trace_prefix << "Tune" << endl;
560                 break;
561             
562         case MIDI::eox:
563                 o << trace_prefix << "End-of-System Exclusive" << endl;
564                 break;
565             
566         case MIDI::timing:
567                 o << trace_prefix << "Timing" << endl;
568                 break;
569             
570         case MIDI::start:
571                 o << trace_prefix << "Start" << endl;
572                 break;
573             
574         case MIDI::stop:
575                 o << trace_prefix << "Stop" << endl;
576                 break;
577             
578         case MIDI::contineu:
579                 o << trace_prefix << "Continue" << endl;
580                 break;
581             
582         case active:
583                 o << trace_prefix << "Active Sense" << endl;
584                 break;
585             
586         default:
587                 o << trace_prefix << "Unrecognized MIDI message" << endl;
588                 break;
589         }
590 }
591 #endif
592
593 int
594 MidiDiskstream::process (nframes_t transport_frame, nframes_t nframes, bool can_record, bool rec_monitors_input)
595 {
596         // FIXME: waay too much code to duplicate (AudioDiskstream::process)
597         int       ret = -1;
598         nframes_t rec_offset = 0;
599         nframes_t rec_nframes = 0;
600         bool      nominally_recording;
601         bool      re = record_enabled ();
602         bool      collect_playback = true;
603
604         /* if we've already processed the frames corresponding to this call,
605            just return. this allows multiple routes that are taking input
606            from this diskstream to call our ::process() method, but have
607            this stuff only happen once. more commonly, it allows both
608            the AudioTrack that is using this AudioDiskstream *and* the Session
609            to call process() without problems.
610            */
611
612         if (_processed) {
613                 return 0;
614         }
615         
616         commit_should_unlock = false;
617
618         check_record_status (transport_frame, nframes, can_record);
619
620         nominally_recording = (can_record && re);
621
622         if (nframes == 0) {
623                 _processed = true;
624                 return 0;
625         }
626
627         /* This lock is held until the end of ::commit, so these two functions
628            must always be called as a pair. The only exception is if this function
629            returns a non-zero value, in which case, ::commit should not be called.
630            */
631
632         // If we can't take the state lock return.
633         if (!state_lock.trylock()) {
634                 return 1;
635         }
636         commit_should_unlock = true;
637         adjust_capture_position = 0;
638
639         if (nominally_recording || (_session.get_record_enabled() && _session.config.get_punch_in())) {
640                 OverlapType ot;
641
642                 ot = coverage (first_recordable_frame, last_recordable_frame, transport_frame, transport_frame + nframes);
643
644                 switch (ot) {
645                         case OverlapNone:
646                                 rec_nframes = 0;
647                                 break;
648
649                         case OverlapInternal:
650                                 /*     ----------    recrange
651                                            |---|       transrange
652                                            */
653                                 rec_nframes = nframes;
654                                 rec_offset = 0;
655                                 break;
656
657                         case OverlapStart:
658                                 /*    |--------|    recrange
659                                           -----|          transrange
660                                           */
661                                 rec_nframes = transport_frame + nframes - first_recordable_frame;
662                                 if (rec_nframes) {
663                                         rec_offset = first_recordable_frame - transport_frame;
664                                 }
665                                 break;
666
667                         case OverlapEnd:
668                                 /*    |--------|    recrange
669                                           |--------  transrange
670                                           */
671                                 rec_nframes = last_recordable_frame - transport_frame;
672                                 rec_offset = 0;
673                                 break;
674
675                         case OverlapExternal:
676                                 /*    |--------|    recrange
677                                           --------------  transrange
678                                           */
679                                 rec_nframes = last_recordable_frame - last_recordable_frame;
680                                 rec_offset = first_recordable_frame - transport_frame;
681                                 break;
682                 }
683
684                 if (rec_nframes && !was_recording) {
685                         capture_captured = 0;
686                         was_recording = true;
687                 }
688         }
689
690
691         if (can_record && !_last_capture_regions.empty()) {
692                 _last_capture_regions.clear ();
693         }
694
695         if (nominally_recording || rec_nframes) {
696
697                 // Pump entire port buffer into the ring buffer (FIXME: split cycles?)
698                 MidiBuffer& buf = _source_port->get_midi_buffer(nframes);
699                 for (MidiBuffer::iterator i = buf.begin(); i != buf.end(); ++i) {
700                         const Evoral::MIDIEvent<MidiBuffer::TimeType> ev(*i, false);
701                         assert(ev.buffer());
702                         _capture_buf->write(ev.time() + transport_frame, ev.type(), ev.size(), ev.buffer());
703                 }
704         
705         } else {
706
707                 if (was_recording) {
708                         finish_capture (rec_monitors_input);
709                 }
710
711         }
712
713         if (rec_nframes) {
714
715                 /* data will be written to disk */
716
717                 if (rec_nframes == nframes && rec_offset == 0) {
718                         playback_distance = nframes;
719                 }
720
721                 adjust_capture_position = rec_nframes;
722
723         } else if (nominally_recording) {
724
725                 /* can't do actual capture yet - waiting for latency effects to finish before we start*/
726
727                 playback_distance = nframes;
728                 collect_playback = false;
729
730         }
731
732         if (collect_playback) {
733
734                 /* we're doing playback */
735
736                 nframes_t necessary_samples;
737
738                 /* no varispeed playback if we're recording, because the output .... TBD */
739
740                 if (rec_nframes == 0 && _actual_speed != 1.0f) {
741                         necessary_samples = (nframes_t) floor ((nframes * fabs (_actual_speed))) + 1;
742                 } else {
743                         necessary_samples = nframes;
744                 }
745
746                 // Pump entire port buffer into playback buffer (FIXME: split cycles?)
747                 MidiBuffer& buf = _source_port->get_midi_buffer(nframes);
748                 for (MidiBuffer::iterator i = buf.begin(); i != buf.end(); ++i) {
749                         const Evoral::MIDIEvent<MidiBuffer::TimeType> ev(*i, false);
750                         assert(ev.buffer());
751                         _playback_buf->write(ev.time() + transport_frame, ev.type(), ev.size(), ev.buffer());
752                 }
753         }
754
755         ret = 0;
756
757         _processed = true;
758
759         if (ret) {
760
761                 /* we're exiting with failure, so ::commit will not
762                    be called. unlock the state lock.
763                    */
764
765                 commit_should_unlock = false;
766                 state_lock.unlock();
767         } 
768
769         return ret;
770 }
771
772 bool
773 MidiDiskstream::commit (nframes_t nframes)
774 {
775         bool need_butler = false;
776
777         if (_actual_speed < 0.0) {
778                 playback_sample -= playback_distance;
779         } else {
780                 playback_sample += playback_distance;
781         }
782
783         if (adjust_capture_position != 0) {
784                 capture_captured += adjust_capture_position;
785                 adjust_capture_position = 0;
786         }
787
788         uint32_t frames_read = g_atomic_int_get(&_frames_read_from_ringbuffer);
789         uint32_t frames_written = g_atomic_int_get(&_frames_written_to_ringbuffer);
790         if ((frames_written - frames_read) + nframes < midi_readahead) {
791                 need_butler = true;
792         }
793
794         /*cerr << "MDS written: " << frames_written << " - read: " << frames_read <<
795                 " = " << frames_written - frames_read
796                 << " + " << nframes << " < " << midi_readahead << " = " << need_butler << ")" << endl;*/
797         
798         if (commit_should_unlock) {
799                 state_lock.unlock();
800         }
801
802         _processed = false;
803
804         return need_butler;
805 }
806
807 void
808 MidiDiskstream::set_pending_overwrite (bool yn)
809 {
810         /* called from audio thread, so we can use the read ptr and playback sample as we wish */
811         
812         pending_overwrite = yn;
813         
814         overwrite_frame = playback_sample;
815 }
816
817 int
818 MidiDiskstream::overwrite_existing_buffers ()
819 {
820         //read(overwrite_frame, disk_io_chunk_frames, false);
821         overwrite_queued = false;
822         pending_overwrite = false;
823
824         return 0;
825 }
826
827 int
828 MidiDiskstream::seek (nframes_t frame, bool complete_refill)
829 {
830         Glib::Mutex::Lock lm (state_lock);
831         int ret = -1;
832         
833         _playback_buf->reset();
834         _capture_buf->reset();
835         g_atomic_int_set(&_frames_read_from_ringbuffer, 0);
836         g_atomic_int_set(&_frames_written_to_ringbuffer, 0);
837
838         playback_sample = frame;
839         file_frame = frame;
840
841         if (complete_refill) {
842                 while ((ret = do_refill_with_alloc ()) > 0) ;
843         } else {
844                 ret = do_refill_with_alloc ();
845         }
846
847         return ret;
848 }
849
850 int
851 MidiDiskstream::can_internal_playback_seek (nframes_t distance)
852 {
853         uint32_t frames_read    = g_atomic_int_get(&_frames_read_from_ringbuffer);
854         uint32_t frames_written = g_atomic_int_get(&_frames_written_to_ringbuffer);
855         return ((frames_written - frames_read) < distance);
856 }
857
858 int
859 MidiDiskstream::internal_playback_seek (nframes_t distance)
860 {
861         first_recordable_frame += distance;
862         playback_sample += distance;
863
864         return 0;
865 }
866
867 /** @a start is set to the new frame position (TIME) read up to */
868 int
869 MidiDiskstream::read (nframes_t& start, nframes_t dur, bool reversed)
870 {       
871         nframes_t this_read = 0;
872         bool reloop = false;
873         nframes_t loop_end = 0;
874         nframes_t loop_start = 0;
875         nframes_t loop_length = 0;
876         Location *loc = 0;
877
878         if (!reversed) {
879                 /* Make the use of a Location atomic for this read operation.
880                    
881                    Note: Locations don't get deleted, so all we care about
882                    when I say "atomic" is that we are always pointing to
883                    the same one and using a start/length values obtained
884                    just once.
885                 */
886                 
887                 if ((loc = loop_location) != 0) {
888                         loop_start = loc->start();
889                         loop_end = loc->end();
890                         loop_length = loop_end - loop_start;
891                 }
892                 
893                 /* if we are looping, ensure that the first frame we read is at the correct
894                    position within the loop.
895                 */
896                 
897                 if (loc && (start >= loop_end)) {
898                         //cerr << "start adjusted from " << start;
899                         start = loop_start + ((start - loop_start) % loop_length);
900                         //cerr << "to " << start << endl;
901                 }
902                 //cerr << "start is " << start << "  loopstart: " << loop_start << "  loopend: " << loop_end << endl;
903         }
904
905         while (dur) {
906
907                 /* take any loop into account. we can't read past the end of the loop. */
908
909                 if (loc && (loop_end - start < dur)) {
910                         this_read = loop_end - start;
911                         //cerr << "reloop true: thisread: " << this_read << "  dur: " << dur << endl;
912                         reloop = true;
913                 } else {
914                         reloop = false;
915                         this_read = dur;
916                 }
917
918                 if (this_read == 0) {
919                         break;
920                 }
921
922                 this_read = min(dur,this_read);
923
924                 if (midi_playlist()->read (*_playback_buf, start, this_read) != this_read) {
925                         error << string_compose(
926                                         _("MidiDiskstream %1: cannot read %2 from playlist at frame %3"),
927                                         _id, this_read, start) << endmsg;
928                         return -1;
929                 }
930
931                 g_atomic_int_add(&_frames_written_to_ringbuffer, this_read);
932
933                 _read_data_count = _playlist->read_data_count();
934                 
935                 if (reversed) {
936
937                         // Swap note ons with note offs here.  etc?
938                         // Fully reversing MIDI requires look-ahead (well, behind) to find previous
939                         // CC values etc.  hard.
940
941                 } else {
942                         
943                         /* if we read to the end of the loop, go back to the beginning */
944                         
945                         if (reloop) {
946                                 // Synthesize LoopEvent here, because the next events
947                                 // written will have non-monotonic timestamps.
948                                 _playback_buf->write(loop_end - 1, LoopEventType, 0, 0);
949                                 cout << "Pushing LoopEvent ts=" << loop_end-1 
950                                      << " start+this_read " << start+this_read << endl;
951
952                                 start = loop_start;
953                         } else {
954                                 start += this_read;
955                         }
956                 } 
957
958                 dur -= this_read;
959                 //offset += this_read;
960         }
961
962         return 0;
963 }
964
965 int
966 MidiDiskstream::do_refill_with_alloc ()
967 {
968         return do_refill();
969 }
970
971 int
972 MidiDiskstream::do_refill ()
973 {
974         int     ret         = 0;
975         size_t  write_space = _playback_buf->write_space();
976         bool    reversed    = (_visible_speed * _session.transport_speed()) < 0.0f;
977
978         if (write_space == 0) {
979                 return 0;
980         }
981         
982         if (reversed) {
983                 return 0;
984         }
985
986         /* at end: nothing to do */
987         if (file_frame == max_frames) {
988                 return 0;
989         }
990
991         // At this point we...
992         assert(_playback_buf->write_space() > 0); // ... have something to write to, and
993         assert(file_frame <= max_frames); // ... something to write
994
995         // now calculate how much time is in the ringbuffer.
996         // and lets write as much as we need to get this to be midi_readahead;
997         uint32_t frames_read = g_atomic_int_get(&_frames_read_from_ringbuffer);
998         uint32_t frames_written = g_atomic_int_get(&_frames_written_to_ringbuffer);
999         if ((frames_written - frames_read) >= midi_readahead) {
1000                 //cout << "MDS Nothing to do. all fine" << endl;
1001                 return 0;
1002         }
1003
1004         nframes_t to_read = midi_readahead - (frames_written - frames_read);
1005
1006         //cout << "MDS read for midi_readahead " << to_read << "  rb_contains: "
1007         //      << frames_written - frames_read << endl;
1008
1009         to_read = min(to_read, (max_frames - file_frame));
1010         
1011         if (read (file_frame, to_read, reversed)) {
1012                 ret = -1;
1013         }
1014                 
1015         return ret;
1016 }
1017
1018 /** Flush pending data to disk.
1019  *
1020  * Important note: this function will write *AT MOST* disk_io_chunk_frames
1021  * of data to disk. it will never write more than that.  If it writes that
1022  * much and there is more than that waiting to be written, it will return 1,
1023  * otherwise 0 on success or -1 on failure.
1024  * 
1025  * If there is less than disk_io_chunk_frames to be written, no data will be
1026  * written at all unless @a force_flush is true.
1027  */
1028 int
1029 MidiDiskstream::do_flush (RunContext /*context*/, bool force_flush)
1030 {
1031         uint32_t to_write;
1032         int32_t ret = 0;
1033         nframes_t total;
1034
1035         _write_data_count = 0;
1036
1037         total = _session.transport_frame() - _last_flush_frame;
1038         
1039         if (_last_flush_frame > _session.transport_frame()
1040                         || _last_flush_frame < capture_start_frame) {
1041                 _last_flush_frame = _session.transport_frame();
1042         }
1043
1044         if (total == 0 || _capture_buf->read_space() == 0
1045                         || (!force_flush && (total < disk_io_chunk_frames && was_recording))) {
1046                 goto out;
1047         }
1048
1049         /* if there are 2+ chunks of disk i/o possible for
1050            this track, let the caller know so that it can arrange
1051            for us to be called again, ASAP.
1052
1053            if we are forcing a flush, then if there is* any* extra
1054            work, let the caller know.
1055
1056            if we are no longer recording and there is any extra work,
1057            let the caller know too.
1058            */
1059
1060         if (total >= 2 * disk_io_chunk_frames || ((force_flush || !was_recording) && total > disk_io_chunk_frames)) {
1061                 ret = 1;
1062         } 
1063
1064         to_write = disk_io_chunk_frames;
1065
1066         assert(!destructive());
1067
1068         if (record_enabled()
1069                         && (   (_session.transport_frame() - _last_flush_frame > disk_io_chunk_frames)
1070                                 || force_flush)) {
1071                 if ((!_write_source) || _write_source->midi_write (*_capture_buf, capture_start_frame, to_write) != to_write) {
1072                         error << string_compose(_("MidiDiskstream %1: cannot write to disk"), _id) << endmsg;
1073                         return -1;
1074                 } else {
1075                         _last_flush_frame = _session.transport_frame();
1076                 }
1077         }
1078
1079 out:
1080         return ret;
1081 }
1082
1083 void
1084 MidiDiskstream::transport_stopped (struct tm& /*when*/, time_t /*twhen*/, bool abort_capture)
1085 {
1086         uint32_t buffer_position;
1087         bool more_work = true;
1088         int err = 0;
1089         boost::shared_ptr<MidiRegion> region;
1090         nframes_t total_capture;
1091         MidiRegion::SourceList srcs;
1092         MidiRegion::SourceList::iterator src;
1093         vector<CaptureInfo*>::iterator ci;
1094         bool mark_write_completed = false;
1095
1096         finish_capture (true);
1097
1098         /* butler is already stopped, but there may be work to do 
1099            to flush remaining data to disk.
1100            */
1101
1102         while (more_work && !err) {
1103                 switch (do_flush (TransportContext, true)) {
1104                         case 0:
1105                                 more_work = false;
1106                                 break;
1107                         case 1:
1108                                 break;
1109                         case -1:
1110                                 error << string_compose(_("MidiDiskstream \"%1\": cannot flush captured data to disk!"), _name) << endmsg;
1111                                 err++;
1112                 }
1113         }
1114
1115         /* XXX is there anything we can do if err != 0 ? */
1116         Glib::Mutex::Lock lm (capture_info_lock);
1117
1118         if (capture_info.empty()) {
1119                 return;
1120         }
1121
1122         if (abort_capture) {
1123
1124                 if (_write_source) {
1125
1126                         _write_source->mark_for_remove ();
1127                         _write_source->drop_references ();
1128                         _write_source.reset();
1129                 }
1130
1131                 /* new source set up in "out" below */
1132
1133         } else {
1134
1135                 assert(_write_source);
1136
1137                 for (total_capture = 0, ci = capture_info.begin(); ci != capture_info.end(); ++ci) {
1138                         total_capture += (*ci)->frames;
1139                 }
1140
1141                 /* figure out the name for this take */
1142         
1143                 srcs.push_back (_write_source);
1144                 _write_source->set_timeline_position (capture_info.front()->start);
1145                 _write_source->set_captured_for (_name);
1146
1147                 string whole_file_region_name;
1148                 whole_file_region_name = region_name_from_path (_write_source->name(), true);
1149
1150                 /* Register a new region with the Session that
1151                    describes the entire source. Do this first
1152                    so that any sub-regions will obviously be
1153                    children of this one (later!)
1154                    */
1155
1156                 try {
1157                         boost::shared_ptr<Region> rx (RegionFactory::create (srcs, 0,
1158                                         total_capture, whole_file_region_name, 0,
1159                                         Region::Flag (Region::DefaultFlags|Region::Automatic|Region::WholeFile)));
1160
1161                         region = boost::dynamic_pointer_cast<MidiRegion> (rx);
1162                         region->special_set_position (capture_info.front()->start);
1163                 }
1164
1165
1166                 catch (failed_constructor& err) {
1167                         error << string_compose(_("%1: could not create region for complete midi file"), _name) << endmsg;
1168                         /* XXX what now? */
1169                 }
1170
1171                 _last_capture_regions.push_back (region);
1172
1173                 // cerr << _name << ": there are " << capture_info.size() << " capture_info records\n";
1174
1175                 XMLNode &before = _playlist->get_state();
1176                 _playlist->freeze ();
1177
1178                 for (buffer_position = 0, ci = capture_info.begin(); ci != capture_info.end(); ++ci) {
1179
1180                         string region_name;
1181
1182                         _session.region_name (region_name, _write_source->name(), false);
1183
1184                         // cerr << _name << ": based on ci of " << (*ci)->start << " for " << (*ci)->frames << " add a region\n";
1185
1186                         try {
1187                                 boost::shared_ptr<Region> rx (RegionFactory::create (srcs, buffer_position, (*ci)->frames, region_name));
1188                                 region = boost::dynamic_pointer_cast<MidiRegion> (rx);
1189                         }
1190
1191                         catch (failed_constructor& err) {
1192                                 error << _("MidiDiskstream: could not create region for captured midi!") << endmsg;
1193                                 continue; /* XXX is this OK? */
1194                         }
1195                         
1196                         region->GoingAway.connect (bind (mem_fun (*this, &Diskstream::remove_region_from_last_capture), boost::weak_ptr<Region>(region)));
1197
1198                         _last_capture_regions.push_back (region);
1199
1200                         // cerr << "add new region, buffer position = " << buffer_position << " @ " << (*ci)->start << endl;
1201
1202                         i_am_the_modifier++;
1203                         _playlist->add_region (region, (*ci)->start);
1204                         i_am_the_modifier--;
1205
1206                         buffer_position += (*ci)->frames;
1207                 }
1208
1209                 _playlist->thaw ();
1210                 XMLNode &after = _playlist->get_state();
1211                 _session.add_command (new MementoCommand<Playlist>(*_playlist, &before, &after));
1212
1213         }
1214
1215         mark_write_completed = true;
1216
1217         reset_write_sources (mark_write_completed);
1218
1219         for (ci = capture_info.begin(); ci != capture_info.end(); ++ci) {
1220                 delete *ci;
1221         }
1222
1223         capture_info.clear ();
1224         capture_start_frame = 0;
1225 }
1226
1227 void
1228 MidiDiskstream::transport_looped (nframes_t transport_frame)
1229 {
1230         if (was_recording) {
1231
1232                 // adjust the capture length knowing that the data will be recorded to disk
1233                 // only necessary after the first loop where we're recording
1234                 if (capture_info.size() == 0) {
1235                         capture_captured += _capture_offset;
1236
1237                         if (_alignment_style == ExistingMaterial) {
1238                                 capture_captured += _session.worst_output_latency();
1239                         } else {
1240                                 capture_captured += _roll_delay;
1241                         }
1242                 }
1243
1244                 finish_capture (true);
1245
1246                 // the next region will start recording via the normal mechanism
1247                 // we'll set the start position to the current transport pos
1248                 // no latency adjustment or capture offset needs to be made, as that already happened the first time
1249                 capture_start_frame = transport_frame;
1250                 first_recordable_frame = transport_frame; // mild lie
1251                 last_recordable_frame = max_frames;
1252                 was_recording = true;
1253         }
1254 }
1255
1256 void
1257 MidiDiskstream::finish_capture (bool /*rec_monitors_input*/)
1258 {
1259         was_recording = false;
1260         
1261         if (capture_captured == 0) {
1262                 return;
1263         }
1264
1265         // Why must we destroy?
1266         assert(!destructive());
1267
1268         CaptureInfo* ci = new CaptureInfo;
1269         
1270         ci->start  = capture_start_frame;
1271         ci->frames = capture_captured;
1272         
1273         /* XXX theoretical race condition here. Need atomic exchange ? 
1274            However, the circumstances when this is called right 
1275            now (either on record-disable or transport_stopped)
1276            mean that no actual race exists. I think ...
1277            We now have a capture_info_lock, but it is only to be used
1278            to synchronize in the transport_stop and the capture info
1279            accessors, so that invalidation will not occur (both non-realtime).
1280         */
1281
1282         // cerr << "Finish capture, add new CI, " << ci->start << '+' << ci->frames << endl;
1283
1284         capture_info.push_back (ci);
1285         capture_captured = 0;
1286 }
1287
1288 void
1289 MidiDiskstream::set_record_enabled (bool yn)
1290 {
1291         if (!recordable() || !_session.record_enabling_legal()) {
1292                 return;
1293         }
1294
1295         assert(!destructive());
1296         
1297         if (yn && _source_port == 0) {
1298
1299                 /* pick up connections not initiated *from* the IO object
1300                    we're associated with.
1301                 */
1302
1303                 get_input_sources ();
1304         }
1305
1306         /* yes, i know that this not proof against race conditions, but its
1307            good enough. i think.
1308         */
1309
1310         if (record_enabled() != yn) {
1311                 if (yn) {
1312                         engage_record_enable ();
1313                 } else {
1314                         disengage_record_enable ();
1315                 }
1316         }
1317 }
1318
1319 void
1320 MidiDiskstream::engage_record_enable ()
1321 {
1322     bool rolling = _session.transport_speed() != 0.0f;
1323
1324         g_atomic_int_set (&_record_enabled, 1);
1325         
1326         if (_source_port && Config->get_monitoring_model() == HardwareMonitoring) {
1327                 _source_port->request_monitor_input (!(_session.config.get_auto_input() && rolling));
1328         }
1329
1330         // FIXME: Why is this necessary?  Isn't needed for AudioDiskstream...
1331         if (!_write_source)
1332                 use_new_write_source();
1333
1334         _write_source->mark_streaming_midi_write_started (_note_mode, _session.transport_frame());
1335
1336         RecordEnableChanged (); /* EMIT SIGNAL */
1337 }
1338
1339 void
1340 MidiDiskstream::disengage_record_enable ()
1341 {
1342         g_atomic_int_set (&_record_enabled, 0);
1343         if (_source_port && Config->get_monitoring_model() == HardwareMonitoring) {
1344                 if (_source_port) {
1345                         _source_port->request_monitor_input (false);
1346                 }
1347         }
1348
1349         RecordEnableChanged (); /* EMIT SIGNAL */
1350 }
1351
1352 XMLNode&
1353 MidiDiskstream::get_state ()
1354 {
1355         XMLNode* node = new XMLNode ("MidiDiskstream");
1356         char buf[64];
1357         LocaleGuard lg (X_("POSIX"));
1358
1359         snprintf (buf, sizeof(buf), "0x%x", _flags);
1360         node->add_property ("flags", buf);
1361
1362         node->add_property("channel-mode", enum_2_string(get_channel_mode()));
1363         
1364         snprintf (buf, sizeof(buf), "0x%x", get_channel_mask());
1365         node->add_property("channel-mask", buf);
1366         
1367         node->add_property ("playlist", _playlist->name());
1368         
1369         snprintf (buf, sizeof(buf), "%f", _visible_speed);
1370         node->add_property ("speed", buf);
1371
1372         node->add_property("name", _name);
1373         id().print(buf, sizeof(buf));
1374         node->add_property("id", buf);
1375
1376         if (_write_source && _session.get_record_enabled()) {
1377
1378                 XMLNode* cs_child = new XMLNode (X_("CapturingSources"));
1379                 XMLNode* cs_grandchild;
1380
1381                 cs_grandchild = new XMLNode (X_("file"));
1382                 cs_grandchild->add_property (X_("path"), _write_source->path());
1383                 cs_child->add_child_nocopy (*cs_grandchild);
1384
1385                 /* store the location where capture will start */
1386
1387                 Location* pi;
1388
1389                 if (_session.config.get_punch_in() && ((pi = _session.locations()->auto_punch_location()) != 0)) {
1390                         snprintf (buf, sizeof (buf), "%" PRId64, pi->start());
1391                 } else {
1392                         snprintf (buf, sizeof (buf), "%" PRIu32, _session.transport_frame());
1393                 }
1394
1395                 cs_child->add_property (X_("at"), buf);
1396                 node->add_child_nocopy (*cs_child);
1397         }
1398
1399         if (_extra_xml) {
1400                 node->add_child_copy (*_extra_xml);
1401         }
1402
1403         return* node;
1404 }
1405
1406 int
1407 MidiDiskstream::set_state (const XMLNode& node)
1408 {
1409         const XMLProperty* prop;
1410         XMLNodeList nlist = node.children();
1411         XMLNodeIterator niter;
1412         uint32_t nchans = 1;
1413         XMLNode* capture_pending_node = 0;
1414         LocaleGuard lg (X_("POSIX"));
1415
1416         in_set_state = true;
1417
1418         for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
1419                 /*if ((*niter)->name() == IO::state_node_name) {
1420                         deprecated_io_node = new XMLNode (**niter);
1421                 }*/
1422                 assert ((*niter)->name() != IO::state_node_name);
1423
1424                 if ((*niter)->name() == X_("CapturingSources")) {
1425                         capture_pending_node = *niter;
1426                 }
1427         }
1428
1429         /* prevent write sources from being created */
1430         
1431         in_set_state = true;
1432         
1433         if ((prop = node.property ("name")) != 0) {
1434                 _name = prop->value();
1435         } 
1436
1437         if ((prop = node.property ("id")) != 0) {
1438                 _id = prop->value ();
1439         }
1440
1441         if ((prop = node.property ("flags")) != 0) {
1442                 _flags = Flag (string_2_enum (prop->value(), _flags));
1443         }
1444
1445         ChannelMode channel_mode = AllChannels;
1446         if ((prop = node.property ("channel-mode")) != 0) {
1447                 channel_mode = ChannelMode (string_2_enum(prop->value(), channel_mode));
1448         }
1449         
1450         unsigned int channel_mask = 0xFFFF;
1451         if ((prop = node.property ("channel-mask")) != 0) {
1452                 sscanf (prop->value().c_str(), "0x%x", &channel_mask);
1453                 if (channel_mask & (~0xFFFF)) {
1454                         warning << _("MidiDiskstream: XML property channel-mask out of range") << endmsg;
1455                 }
1456         }
1457
1458         set_channel_mode(channel_mode, channel_mask);
1459         
1460         if ((prop = node.property ("channels")) != 0) {
1461                 nchans = atoi (prop->value().c_str());
1462         }
1463         
1464         if ((prop = node.property ("playlist")) == 0) {
1465                 return -1;
1466         }
1467
1468         {
1469                 bool had_playlist = (_playlist != 0);
1470         
1471                 if (find_and_use_playlist (prop->value())) {
1472                         return -1;
1473                 }
1474
1475                 if (!had_playlist) {
1476                         _playlist->set_orig_diskstream_id (_id);
1477                 }
1478                 
1479                 if (capture_pending_node) {
1480                         use_pending_capture_data (*capture_pending_node);
1481                 }
1482
1483         }
1484
1485         if ((prop = node.property ("speed")) != 0) {
1486                 double sp = atof (prop->value().c_str());
1487
1488                 if (realtime_set_speed (sp, false)) {
1489                         non_realtime_set_speed ();
1490                 }
1491         }
1492
1493         in_set_state = false;
1494
1495         /* make sure this is clear before we do anything else */
1496
1497         // FIXME?
1498         //_capturing_source = 0;
1499
1500         /* write sources are handled when we handle the input set 
1501            up of the IO that owns this DS (::non_realtime_input_change())
1502         */
1503                 
1504         in_set_state = false;
1505
1506         return 0;
1507 }
1508
1509 int
1510 MidiDiskstream::use_new_write_source (uint32_t n)
1511 {
1512         if (!recordable()) {
1513                 return 1;
1514         }
1515
1516         assert(n == 0);
1517
1518         if (_write_source) {
1519
1520                 if (_write_source->is_empty ()) {
1521                         _write_source->mark_for_remove ();
1522                         _write_source.reset();
1523                 } else {
1524                         _write_source.reset();
1525                 }
1526         }
1527
1528         try {
1529                 _write_source = boost::dynamic_pointer_cast<SMFSource>(_session.create_midi_source_for_session (*this));
1530                 if (!_write_source) {
1531                         throw failed_constructor();
1532                 }
1533         } 
1534
1535         catch (failed_constructor &err) {
1536                 error << string_compose (_("%1:%2 new capture file not initialized correctly"), _name, n) << endmsg;
1537                 _write_source.reset();
1538                 return -1;
1539         }
1540
1541         _write_source->set_allow_remove_if_empty (true);
1542
1543         return 0;
1544 }
1545
1546 void
1547 MidiDiskstream::reset_write_sources (bool mark_write_complete, bool /*force*/)
1548 {
1549         if (!recordable()) {
1550                 return;
1551         }
1552
1553         if (_write_source && mark_write_complete) {
1554                 _write_source->mark_streaming_write_completed ();
1555         }
1556
1557         use_new_write_source (0);
1558                         
1559         if (record_enabled()) {
1560                 //_capturing_sources.push_back (_write_source);
1561         }
1562 }
1563
1564 int
1565 MidiDiskstream::rename_write_sources ()
1566 {
1567         if (_write_source != 0) {
1568                 _write_source->set_source_name (_name, destructive());
1569                 /* XXX what to do if this fails ? */
1570         }
1571         return 0;
1572 }
1573
1574 void
1575 MidiDiskstream::set_block_size (nframes_t /*nframes*/)
1576 {
1577 }
1578
1579 void
1580 MidiDiskstream::allocate_temporary_buffers ()
1581 {
1582 }
1583
1584 void
1585 MidiDiskstream::monitor_input (bool yn)
1586 {
1587         if (_source_port)
1588                 _source_port->ensure_monitor_input (yn);
1589 }
1590
1591 void
1592 MidiDiskstream::set_align_style_from_io ()
1593 {
1594         bool have_physical = false;
1595
1596         if (_io == 0) {
1597                 return;
1598         }
1599
1600         get_input_sources ();
1601         
1602         if (_source_port && _source_port->flags() & JackPortIsPhysical) {
1603                 have_physical = true;
1604         }
1605
1606         if (have_physical) {
1607                 set_align_style (ExistingMaterial);
1608         } else {
1609                 set_align_style (CaptureTime);
1610         }
1611 }
1612
1613
1614 float
1615 MidiDiskstream::playback_buffer_load () const
1616 {
1617         return (float) ((double) _playback_buf->read_space()/
1618                         (double) _playback_buf->capacity());
1619 }
1620
1621 float
1622 MidiDiskstream::capture_buffer_load () const
1623 {
1624         return (float) ((double) _capture_buf->write_space()/
1625                         (double) _capture_buf->capacity());
1626 }
1627
1628 int
1629 MidiDiskstream::use_pending_capture_data (XMLNode& /*node*/)
1630 {
1631         return 0;
1632 }
1633
1634 /** Writes playback events in the given range to \a dst, translating time stamps
1635  * so that an event at \a start has time = 0
1636  */
1637 void
1638 MidiDiskstream::get_playback (MidiBuffer& dst, nframes_t start, nframes_t end)
1639 {
1640         dst.clear();
1641         assert(dst.size() == 0);
1642         
1643         // Reverse.  ... We just don't do reverse, ok?  Back off.
1644         if (end <= start) {
1645                 return;
1646         }
1647
1648         // Translates stamps to be relative to start
1649
1650
1651         _playback_buf->read(dst, start, end);
1652
1653 #if 0
1654         const size_t events_read = _playback_buf->read(dst, start, end);
1655         cout << _name << ": MDS events read = " << events_read
1656              << " start = " << start << " end = " << end
1657              << " readspace " << _playback_buf->read_space()
1658              << " writespace " << _playback_buf->write_space() << endl;
1659 #endif
1660         
1661         gint32 frames_read = end - start;
1662         g_atomic_int_add(&_frames_read_from_ringbuffer, frames_read);
1663 }
1664