SDL  2.0
SDL_audio.c
Go to the documentation of this file.
1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
4 
5  This software is provided 'as-is', without any express or implied
6  warranty. In no event will the authors be held liable for any damages
7  arising from the use of this software.
8 
9  Permission is granted to anyone to use this software for any purpose,
10  including commercial applications, and to alter it and redistribute it
11  freely, subject to the following restrictions:
12 
13  1. The origin of this software must not be misrepresented; you must not
14  claim that you wrote the original software. If you use this software
15  in a product, an acknowledgment in the product documentation would be
16  appreciated but is not required.
17  2. Altered source versions must be plainly marked as such, and must not be
18  misrepresented as being the original software.
19  3. This notice may not be removed or altered from any source distribution.
20 */
21 #include "../SDL_internal.h"
22 
23 /* Allow access to a raw mixing buffer */
24 
25 #include "SDL.h"
26 #include "SDL_audio.h"
27 #include "SDL_audio_c.h"
28 #include "SDL_sysaudio.h"
29 #include "../thread/SDL_systhread.h"
30 
31 #define _THIS SDL_AudioDevice *_this
32 
35 
36 /*
37  * Not all of these will be compiled and linked in, but it's convenient
38  * to have a complete list here and saves yet-another block of #ifdefs...
39  * Please see bootstrap[], below, for the actual #ifdef mess.
40  */
65 
66 /* Available audio drivers */
67 static const AudioBootStrap *const bootstrap[] = {
68 #if SDL_AUDIO_DRIVER_PULSEAUDIO
70 #endif
71 #if SDL_AUDIO_DRIVER_ALSA
73 #endif
74 #if SDL_AUDIO_DRIVER_SNDIO
76 #endif
77 #if SDL_AUDIO_DRIVER_BSD
79 #endif
80 #if SDL_AUDIO_DRIVER_OSS
82 #endif
83 #if SDL_AUDIO_DRIVER_QSA
85 #endif
86 #if SDL_AUDIO_DRIVER_SUNAUDIO
88 #endif
89 #if SDL_AUDIO_DRIVER_ARTS
91 #endif
92 #if SDL_AUDIO_DRIVER_ESD
94 #endif
95 #if SDL_AUDIO_DRIVER_NACL
97 #endif
98 #if SDL_AUDIO_DRIVER_NAS
100 #endif
101 #if SDL_AUDIO_DRIVER_XAUDIO2
103 #endif
104 #if SDL_AUDIO_DRIVER_DSOUND
106 #endif
107 #if SDL_AUDIO_DRIVER_WINMM
109 #endif
110 #if SDL_AUDIO_DRIVER_PAUDIO
112 #endif
113 #if SDL_AUDIO_DRIVER_HAIKU
115 #endif
116 #if SDL_AUDIO_DRIVER_COREAUDIO
118 #endif
119 #if SDL_AUDIO_DRIVER_DISK
121 #endif
122 #if SDL_AUDIO_DRIVER_DUMMY
124 #endif
125 #if SDL_AUDIO_DRIVER_FUSIONSOUND
127 #endif
128 #if SDL_AUDIO_DRIVER_ANDROID
130 #endif
131 #if SDL_AUDIO_DRIVER_PSP
133 #endif
134 #if SDL_AUDIO_DRIVER_EMSCRIPTEN
136 #endif
137  NULL
138 };
139 
140 static SDL_AudioDevice *
142 {
143  id--;
144  if ((id >= SDL_arraysize(open_devices)) || (open_devices[id] == NULL)) {
145  SDL_SetError("Invalid audio device ID");
146  return NULL;
147  }
148 
149  return open_devices[id];
150 }
151 
152 
153 /* stubs for audio drivers that don't need a specific entry point... */
154 static void
156 {
157  /* you have to write your own implementation if these assertions fail. */
159  SDL_assert(current_audio.impl.OnlyHasDefaultCaptureDevice || !current_audio.impl.HasCaptureSupport);
160 
161  SDL_AddAudioDevice(SDL_FALSE, DEFAULT_OUTPUT_DEVNAME, (void *) ((size_t) 0x1));
162  if (current_audio.impl.HasCaptureSupport) {
163  SDL_AddAudioDevice(SDL_TRUE, DEFAULT_INPUT_DEVNAME, (void *) ((size_t) 0x2));
164  }
165 }
166 
167 static void
169 { /* no-op. */
170 }
171 
172 static void
174 { /* no-op. */
175 }
176 
177 static void
179 { /* no-op. */
180 }
181 
182 static int
184 {
185  return 0;
186 }
187 
188 static Uint8 *
190 {
191  return NULL;
192 }
193 
194 static int
196 {
197  return -1; /* just fail immediately. */
198 }
199 
200 static void
202 { /* no-op. */
203 }
204 
205 static void
207 { /* no-op. */
208 }
209 
210 static void
212 { /* no-op. */
213 }
214 
215 static void
217 { /* no-op. */
218 }
219 
220 static void
222 { /* no-op. */
223 }
224 
225 
226 static int
227 SDL_AudioOpenDevice_Default(_THIS, void *handle, const char *devname, int iscapture)
228 {
229  return SDL_Unsupported();
230 }
231 
232 static SDL_INLINE SDL_bool
234 {
235  /* The device thread locks the same mutex, but not through the public API.
236  This check is in case the application, in the audio callback,
237  tries to lock the thread that we've already locked from the
238  device thread...just in case we only have non-recursive mutexes. */
239  if (device->thread && (SDL_ThreadID() == device->threadid)) {
240  return SDL_TRUE;
241  }
242 
243  return SDL_FALSE;
244 }
245 
246 static void
248 {
249  if (!is_in_audio_device_thread(device)) {
250  SDL_LockMutex(device->mixer_lock);
251  }
252 }
253 
254 static void
256 {
257  if (!is_in_audio_device_thread(device)) {
258  SDL_UnlockMutex(device->mixer_lock);
259  }
260 }
261 
262 static void
264 {
265 }
266 
267 static void
269 {
270  /*
271  * Fill in stub functions for unused driver entry points. This lets us
272  * blindly call them without having to check for validity first.
273  */
274 
275  if (current_audio.impl.SkipMixerLock) {
276  if (current_audio.impl.LockDevice == NULL) {
278  }
279  if (current_audio.impl.UnlockDevice == NULL) {
281  }
282  }
283 
284 #define FILL_STUB(x) \
285  if (current_audio.impl.x == NULL) { \
286  current_audio.impl.x = SDL_Audio##x##_Default; \
287  }
288  FILL_STUB(DetectDevices);
289  FILL_STUB(OpenDevice);
290  FILL_STUB(ThreadInit);
291  FILL_STUB(WaitDevice);
292  FILL_STUB(PlayDevice);
293  FILL_STUB(GetPendingBytes);
294  FILL_STUB(GetDeviceBuf);
295  FILL_STUB(CaptureFromDevice);
296  FILL_STUB(FlushCapture);
297  FILL_STUB(PrepareToClose);
298  FILL_STUB(CloseDevice);
299  FILL_STUB(LockDevice);
300  FILL_STUB(UnlockDevice);
301  FILL_STUB(FreeDeviceHandle);
302  FILL_STUB(Deinitialize);
303 #undef FILL_STUB
304 }
305 
306 
307 /* device hotplug support... */
308 
309 static int
310 add_audio_device(const char *name, void *handle, SDL_AudioDeviceItem **devices, int *devCount)
311 {
312  int retval = -1;
313  const size_t size = sizeof (SDL_AudioDeviceItem) + SDL_strlen(name) + 1;
315  if (item == NULL) {
316  return -1;
317  }
318 
319  SDL_assert(handle != NULL); /* we reserve NULL, audio backends can't use it. */
320 
321  item->handle = handle;
322  SDL_strlcpy(item->name, name, size - sizeof (SDL_AudioDeviceItem));
323 
324  SDL_LockMutex(current_audio.detectionLock);
325  item->next = *devices;
326  *devices = item;
327  retval = (*devCount)++;
328  SDL_UnlockMutex(current_audio.detectionLock);
329 
330  return retval;
331 }
332 
333 static SDL_INLINE int
334 add_capture_device(const char *name, void *handle)
335 {
336  SDL_assert(current_audio.impl.HasCaptureSupport);
337  return add_audio_device(name, handle, &current_audio.inputDevices, &current_audio.inputDeviceCount);
338 }
339 
340 static SDL_INLINE int
341 add_output_device(const char *name, void *handle)
342 {
343  return add_audio_device(name, handle, &current_audio.outputDevices, &current_audio.outputDeviceCount);
344 }
345 
346 static void
347 free_device_list(SDL_AudioDeviceItem **devices, int *devCount)
348 {
349  SDL_AudioDeviceItem *item, *next;
350  for (item = *devices; item != NULL; item = next) {
351  next = item->next;
352  if (item->handle != NULL) {
353  current_audio.impl.FreeDeviceHandle(item->handle);
354  }
355  SDL_free(item);
356  }
357  *devices = NULL;
358  *devCount = 0;
359 }
360 
361 
362 /* The audio backends call this when a new device is plugged in. */
363 void
364 SDL_AddAudioDevice(const int iscapture, const char *name, void *handle)
365 {
366  const int device_index = iscapture ? add_capture_device(name, handle) : add_output_device(name, handle);
367  if (device_index != -1) {
368  /* Post the event, if desired */
371  SDL_zero(event);
372  event.adevice.type = SDL_AUDIODEVICEADDED;
373  event.adevice.which = device_index;
374  event.adevice.iscapture = iscapture;
375  SDL_PushEvent(&event);
376  }
377  }
378 }
379 
380 /* The audio backends call this when a currently-opened device is lost. */
382 {
383  SDL_assert(get_audio_device(device->id) == device);
384 
385  if (!SDL_AtomicGet(&device->enabled)) {
386  return;
387  }
388 
389  /* Ends the audio callback and mark the device as STOPPED, but the
390  app still needs to close the device to free resources. */
391  current_audio.impl.LockDevice(device);
392  SDL_AtomicSet(&device->enabled, 0);
393  current_audio.impl.UnlockDevice(device);
394 
395  /* Post the event, if desired */
398  SDL_zero(event);
399  event.adevice.type = SDL_AUDIODEVICEREMOVED;
400  event.adevice.which = device->id;
401  event.adevice.iscapture = device->iscapture ? 1 : 0;
402  SDL_PushEvent(&event);
403  }
404 }
405 
406 static void
407 mark_device_removed(void *handle, SDL_AudioDeviceItem *devices, SDL_bool *removedFlag)
408 {
409  SDL_AudioDeviceItem *item;
410  SDL_assert(handle != NULL);
411  for (item = devices; item != NULL; item = item->next) {
412  if (item->handle == handle) {
413  item->handle = NULL;
414  *removedFlag = SDL_TRUE;
415  return;
416  }
417  }
418 }
419 
420 /* The audio backends call this when a device is removed from the system. */
421 void
422 SDL_RemoveAudioDevice(const int iscapture, void *handle)
423 {
424  int device_index;
425  SDL_AudioDevice *device = NULL;
426 
427  SDL_LockMutex(current_audio.detectionLock);
428  if (iscapture) {
429  mark_device_removed(handle, current_audio.inputDevices, &current_audio.captureDevicesRemoved);
430  } else {
431  mark_device_removed(handle, current_audio.outputDevices, &current_audio.outputDevicesRemoved);
432  }
433  for (device_index = 0; device_index < SDL_arraysize(open_devices); device_index++)
434  {
435  device = open_devices[device_index];
436  if (device != NULL && device->handle == handle)
437  {
439  break;
440  }
441  }
442  SDL_UnlockMutex(current_audio.detectionLock);
443 
444  current_audio.impl.FreeDeviceHandle(handle);
445 }
446 
447 
448 
449 /* buffer queueing support... */
450 
451 /* this expects that you managed thread safety elsewhere. */
452 static void
454 {
455  while (packet) {
456  SDL_AudioBufferQueue *next = packet->next;
457  SDL_free(packet);
458  packet = next;
459  }
460 }
461 
462 /* NOTE: This assumes you'll hold the mixer lock before calling! */
463 static int
465 {
466  SDL_AudioBufferQueue *orighead;
467  SDL_AudioBufferQueue *origtail;
468  Uint32 origlen;
469  Uint32 datalen;
470 
471  orighead = device->buffer_queue_head;
472  origtail = device->buffer_queue_tail;
473  origlen = origtail ? origtail->datalen : 0;
474 
475  while (len > 0) {
476  SDL_AudioBufferQueue *packet = device->buffer_queue_tail;
477  SDL_assert(!packet || (packet->datalen <= SDL_AUDIOBUFFERQUEUE_PACKETLEN));
478  if (!packet || (packet->datalen >= SDL_AUDIOBUFFERQUEUE_PACKETLEN)) {
479  /* tail packet missing or completely full; we need a new packet. */
480  packet = device->buffer_queue_pool;
481  if (packet != NULL) {
482  /* we have one available in the pool. */
483  device->buffer_queue_pool = packet->next;
484  } else {
485  /* Have to allocate a new one! */
487  if (packet == NULL) {
488  /* uhoh, reset so we've queued nothing new, free what we can. */
489  if (!origtail) {
490  packet = device->buffer_queue_head; /* whole queue. */
491  } else {
492  packet = origtail->next; /* what we added to existing queue. */
493  origtail->next = NULL;
494  origtail->datalen = origlen;
495  }
496  device->buffer_queue_head = orighead;
497  device->buffer_queue_tail = origtail;
498  device->buffer_queue_pool = NULL;
499 
500  free_audio_queue(packet); /* give back what we can. */
501 
502  return SDL_OutOfMemory();
503  }
504  }
505  packet->datalen = 0;
506  packet->startpos = 0;
507  packet->next = NULL;
508 
509  SDL_assert((device->buffer_queue_head != NULL) == (device->queued_bytes != 0));
510  if (device->buffer_queue_tail == NULL) {
511  device->buffer_queue_head = packet;
512  } else {
513  device->buffer_queue_tail->next = packet;
514  }
515  device->buffer_queue_tail = packet;
516  }
517 
518  datalen = SDL_min(len, SDL_AUDIOBUFFERQUEUE_PACKETLEN - packet->datalen);
519  SDL_memcpy(packet->data + packet->datalen, data, datalen);
520  data += datalen;
521  len -= datalen;
522  packet->datalen += datalen;
523  device->queued_bytes += datalen;
524  }
525 
526  return 0;
527 }
528 
529 /* NOTE: This assumes you'll hold the mixer lock before calling! */
530 static Uint32
532 {
533  SDL_AudioBufferQueue *packet;
534  Uint8 *ptr = stream;
535 
536  while ((len > 0) && ((packet = device->buffer_queue_head) != NULL)) {
537  const Uint32 avail = packet->datalen - packet->startpos;
538  const Uint32 cpy = SDL_min(len, avail);
539  SDL_assert(device->queued_bytes >= avail);
540 
541  SDL_memcpy(ptr, packet->data + packet->startpos, cpy);
542  packet->startpos += cpy;
543  ptr += cpy;
544  device->queued_bytes -= cpy;
545  len -= cpy;
546 
547  if (packet->startpos == packet->datalen) { /* packet is done, put it in the pool. */
548  device->buffer_queue_head = packet->next;
549  SDL_assert((packet->next != NULL) || (packet == device->buffer_queue_tail));
550  packet->next = device->buffer_queue_pool;
551  device->buffer_queue_pool = packet;
552  }
553  }
554 
555  SDL_assert((device->buffer_queue_head != NULL) == (device->queued_bytes != 0));
556 
557  if (device->buffer_queue_head == NULL) {
558  device->buffer_queue_tail = NULL; /* in case we drained the queue entirely. */
559  }
560 
561  return (Uint32) (ptr - stream);
562 }
563 
564 static void SDLCALL
566 {
567  /* this function always holds the mixer lock before being called. */
568  SDL_AudioDevice *device = (SDL_AudioDevice *) userdata;
569  Uint32 written;
570 
571  SDL_assert(device != NULL); /* this shouldn't ever happen, right?! */
572  SDL_assert(!device->iscapture); /* this shouldn't ever happen, right?! */
573  SDL_assert(len >= 0); /* this shouldn't ever happen, right?! */
574 
575  written = dequeue_audio_from_device(device, stream, (Uint32) len);
576  stream += written;
577  len -= (int) written;
578 
579  if (len > 0) { /* fill any remaining space in the stream with silence. */
580  SDL_assert(device->buffer_queue_head == NULL);
581  SDL_memset(stream, device->spec.silence, len);
582  }
583 }
584 
585 static void SDLCALL
587 {
588  /* this function always holds the mixer lock before being called. */
589  SDL_AudioDevice *device = (SDL_AudioDevice *) userdata;
590 
591  SDL_assert(device != NULL); /* this shouldn't ever happen, right?! */
592  SDL_assert(device->iscapture); /* this shouldn't ever happen, right?! */
593  SDL_assert(len >= 0); /* this shouldn't ever happen, right?! */
594 
595  /* note that if this needs to allocate more space and run out of memory,
596  we have no choice but to quietly drop the data and hope it works out
597  later, but you probably have bigger problems in this case anyhow. */
598  queue_audio_to_device(device, stream, (Uint32) len);
599 }
600 
601 int
603 {
604  SDL_AudioDevice *device = get_audio_device(devid);
605  int rc = 0;
606 
607  if (!device) {
608  return -1; /* get_audio_device() will have set the error state */
609  } else if (device->iscapture) {
610  return SDL_SetError("This is a capture device, queueing not allowed");
611  } else if (device->spec.callback != SDL_BufferQueueDrainCallback) {
612  return SDL_SetError("Audio device has a callback, queueing not allowed");
613  }
614 
615  if (len > 0) {
616  current_audio.impl.LockDevice(device);
617  rc = queue_audio_to_device(device, data, len);
618  current_audio.impl.UnlockDevice(device);
619  }
620 
621  return rc;
622 }
623 
624 Uint32
626 {
627  SDL_AudioDevice *device = get_audio_device(devid);
628  Uint32 rc;
629 
630  if ( (len == 0) || /* nothing to do? */
631  (!device) || /* called with bogus device id */
632  (!device->iscapture) || /* playback devices can't dequeue */
633  (device->spec.callback != SDL_BufferQueueFillCallback) ) { /* not set for queueing */
634  return 0; /* just report zero bytes dequeued. */
635  }
636 
637  current_audio.impl.LockDevice(device);
638  rc = dequeue_audio_from_device(device, data, len);
639  current_audio.impl.UnlockDevice(device);
640  return rc;
641 }
642 
643 Uint32
645 {
646  Uint32 retval = 0;
647  SDL_AudioDevice *device = get_audio_device(devid);
648 
649  if (!device) {
650  return 0;
651  }
652 
653  /* Nothing to do unless we're set up for queueing. */
654  if (device->spec.callback == SDL_BufferQueueDrainCallback) {
655  current_audio.impl.LockDevice(device);
656  retval = device->queued_bytes + current_audio.impl.GetPendingBytes(device);
657  current_audio.impl.UnlockDevice(device);
658  } else if (device->spec.callback == SDL_BufferQueueFillCallback) {
659  current_audio.impl.LockDevice(device);
660  retval = device->queued_bytes;
661  current_audio.impl.UnlockDevice(device);
662  }
663 
664  return retval;
665 }
666 
667 void
669 {
670  SDL_AudioDevice *device = get_audio_device(devid);
671  SDL_AudioBufferQueue *packet;
672 
673  if (!device) {
674  return; /* nothing to do. */
675  }
676 
677  /* Blank out the device and release the mutex. Free it afterwards. */
678  current_audio.impl.LockDevice(device);
679 
680  /* merge the available pool and the current queue into one list. */
681  packet = device->buffer_queue_head;
682  if (packet) {
683  device->buffer_queue_tail->next = device->buffer_queue_pool;
684  } else {
685  packet = device->buffer_queue_pool;
686  }
687 
688  /* Remove the queued packets from the device. */
689  device->buffer_queue_tail = NULL;
690  device->buffer_queue_head = NULL;
691  device->queued_bytes = 0;
692  device->buffer_queue_pool = packet;
693 
694  /* Keep up to two packets in the pool to reduce future malloc pressure. */
695  if (packet) {
696  if (!packet->next) {
697  packet = NULL; /* one packet (the only one) for the pool. */
698  } else {
699  SDL_AudioBufferQueue *next = packet->next->next;
700  packet->next->next = NULL; /* two packets for the pool. */
701  packet = next; /* rest will be freed. */
702  }
703  }
704 
705  current_audio.impl.UnlockDevice(device);
706 
707  /* free any extra packets we didn't keep in the pool. */
708  free_audio_queue(packet);
709 }
710 
711 
712 /* The general mixing thread function */
713 static int SDLCALL
714 SDL_RunAudio(void *devicep)
715 {
716  SDL_AudioDevice *device = (SDL_AudioDevice *) devicep;
717  const int silence = (int) device->spec.silence;
718  const Uint32 delay = ((device->spec.samples * 1000) / device->spec.freq);
719  const int stream_len = (device->convert.needed) ? device->convert.len : device->spec.size;
720  Uint8 *stream;
721  void *udata = device->spec.userdata;
722  void (SDLCALL *callback) (void *, Uint8 *, int) = device->spec.callback;
723 
724  SDL_assert(!device->iscapture);
725 
726  /* The audio mixing is always a high priority thread */
728 
729  /* Perform any thread setup */
730  device->threadid = SDL_ThreadID();
731  current_audio.impl.ThreadInit(device);
732 
733  /* Loop, filling the audio buffers */
734  while (!SDL_AtomicGet(&device->shutdown)) {
735  /* Fill the current buffer with sound */
736  if (device->convert.needed) {
737  stream = device->convert.buf;
738  } else if (SDL_AtomicGet(&device->enabled)) {
739  stream = current_audio.impl.GetDeviceBuf(device);
740  } else {
741  /* if the device isn't enabled, we still write to the
742  fake_stream, so the app's callback will fire with
743  a regular frequency, in case they depend on that
744  for timing or progress. They can use hotplug
745  now to know if the device failed. */
746  stream = NULL;
747  }
748 
749  if (stream == NULL) {
750  stream = device->fake_stream;
751  }
752 
753  /* !!! FIXME: this should be LockDevice. */
754  if ( SDL_AtomicGet(&device->enabled) ) {
755  SDL_LockMutex(device->mixer_lock);
756  if (SDL_AtomicGet(&device->paused)) {
757  SDL_memset(stream, silence, stream_len);
758  } else {
759  (*callback) (udata, stream, stream_len);
760  }
761  SDL_UnlockMutex(device->mixer_lock);
762  }
763 
764  /* Convert the audio if necessary */
765  if (device->convert.needed && SDL_AtomicGet(&device->enabled)) {
766  SDL_ConvertAudio(&device->convert);
767  stream = current_audio.impl.GetDeviceBuf(device);
768  if (stream == NULL) {
769  stream = device->fake_stream;
770  } else {
771  SDL_memcpy(stream, device->convert.buf,
772  device->convert.len_cvt);
773  }
774  }
775 
776  /* Ready current buffer for play and change current buffer */
777  if (stream == device->fake_stream) {
778  SDL_Delay(delay);
779  } else {
780  current_audio.impl.PlayDevice(device);
781  current_audio.impl.WaitDevice(device);
782  }
783  }
784 
785  current_audio.impl.PrepareToClose(device);
786 
787  /* Wait for the audio to drain. */
788  SDL_Delay(((device->spec.samples * 1000) / device->spec.freq) * 2);
789 
790  return 0;
791 }
792 
793 /* The general capture thread function */
794 static int SDLCALL
795 SDL_CaptureAudio(void *devicep)
796 {
797  SDL_AudioDevice *device = (SDL_AudioDevice *) devicep;
798  const int silence = (int) device->spec.silence;
799  const Uint32 delay = ((device->spec.samples * 1000) / device->spec.freq);
800  const int stream_len = (device->convert.needed) ? device->convert.len : device->spec.size;
801  Uint8 *stream;
802  void *udata = device->spec.userdata;
803  void (SDLCALL *callback) (void *, Uint8 *, int) = device->spec.callback;
804 
805  SDL_assert(device->iscapture);
806 
807  /* The audio mixing is always a high priority thread */
809 
810  /* Perform any thread setup */
811  device->threadid = SDL_ThreadID();
812  current_audio.impl.ThreadInit(device);
813 
814  /* Loop, filling the audio buffers */
815  while (!SDL_AtomicGet(&device->shutdown)) {
816  int still_need;
817  Uint8 *ptr;
818 
819  if (!SDL_AtomicGet(&device->enabled) || SDL_AtomicGet(&device->paused)) {
820  SDL_Delay(delay); /* just so we don't cook the CPU. */
821  current_audio.impl.FlushCapture(device); /* dump anything pending. */
822  continue;
823  }
824 
825  /* Fill the current buffer with sound */
826  still_need = stream_len;
827  if (device->convert.needed) {
828  ptr = stream = device->convert.buf;
829  } else {
830  /* just use the "fake" stream to hold data read from the device. */
831  ptr = stream = device->fake_stream;
832  }
833 
834  /* We still read from the device when "paused" to keep the state sane,
835  and block when there isn't data so this thread isn't eating CPU.
836  But we don't process it further or call the app's callback. */
837 
838  while (still_need > 0) {
839  const int rc = current_audio.impl.CaptureFromDevice(device, ptr, still_need);
840  SDL_assert(rc <= still_need); /* device should not overflow buffer. :) */
841  if (rc > 0) {
842  still_need -= rc;
843  ptr += rc;
844  } else { /* uhoh, device failed for some reason! */
846  break;
847  }
848  }
849 
850  if (still_need > 0) {
851  /* Keep any data we already read, silence the rest. */
852  SDL_memset(ptr, silence, still_need);
853  }
854 
855  if (device->convert.needed) {
856  SDL_ConvertAudio(&device->convert);
857  }
858 
859  /* !!! FIXME: this should be LockDevice. */
860  SDL_LockMutex(device->mixer_lock);
861  if (SDL_AtomicGet(&device->paused)) {
862  current_audio.impl.FlushCapture(device); /* one snuck in! */
863  } else {
864  (*callback)(udata, stream, stream_len);
865  }
866  SDL_UnlockMutex(device->mixer_lock);
867  }
868 
869  current_audio.impl.FlushCapture(device);
870 
871  return 0;
872 }
873 
874 
875 static SDL_AudioFormat
876 SDL_ParseAudioFormat(const char *string)
877 {
878 #define CHECK_FMT_STRING(x) if (SDL_strcmp(string, #x) == 0) return AUDIO_##x
879  CHECK_FMT_STRING(U8);
880  CHECK_FMT_STRING(S8);
881  CHECK_FMT_STRING(U16LSB);
882  CHECK_FMT_STRING(S16LSB);
883  CHECK_FMT_STRING(U16MSB);
884  CHECK_FMT_STRING(S16MSB);
885  CHECK_FMT_STRING(U16SYS);
886  CHECK_FMT_STRING(S16SYS);
887  CHECK_FMT_STRING(U16);
888  CHECK_FMT_STRING(S16);
889  CHECK_FMT_STRING(S32LSB);
890  CHECK_FMT_STRING(S32MSB);
891  CHECK_FMT_STRING(S32SYS);
893  CHECK_FMT_STRING(F32LSB);
894  CHECK_FMT_STRING(F32MSB);
895  CHECK_FMT_STRING(F32SYS);
896  CHECK_FMT_STRING(F32);
897 #undef CHECK_FMT_STRING
898  return 0;
899 }
900 
901 int
903 {
904  return SDL_arraysize(bootstrap) - 1;
905 }
906 
907 const char *
909 {
910  if (index >= 0 && index < SDL_GetNumAudioDrivers()) {
911  return bootstrap[index]->name;
912  }
913  return NULL;
914 }
915 
916 int
917 SDL_AudioInit(const char *driver_name)
918 {
919  int i = 0;
920  int initialized = 0;
921  int tried_to_init = 0;
922 
924  SDL_AudioQuit(); /* shutdown driver if already running. */
925  }
926 
927  SDL_zero(current_audio);
928  SDL_zero(open_devices);
929 
930  /* Select the proper audio driver */
931  if (driver_name == NULL) {
932  driver_name = SDL_getenv("SDL_AUDIODRIVER");
933  }
934 
935  for (i = 0; (!initialized) && (bootstrap[i]); ++i) {
936  /* make sure we should even try this driver before doing so... */
937  const AudioBootStrap *backend = bootstrap[i];
938  if ((driver_name && (SDL_strncasecmp(backend->name, driver_name, SDL_strlen(driver_name)) != 0)) ||
939  (!driver_name && backend->demand_only)) {
940  continue;
941  }
942 
943  tried_to_init = 1;
944  SDL_zero(current_audio);
945  current_audio.name = backend->name;
946  current_audio.desc = backend->desc;
947  initialized = backend->init(&current_audio.impl);
948  }
949 
950  if (!initialized) {
951  /* specific drivers will set the error message if they fail... */
952  if (!tried_to_init) {
953  if (driver_name) {
954  SDL_SetError("Audio target '%s' not available", driver_name);
955  } else {
956  SDL_SetError("No available audio device");
957  }
958  }
959 
960  SDL_zero(current_audio);
961  return -1; /* No driver was available, so fail. */
962  }
963 
964  current_audio.detectionLock = SDL_CreateMutex();
965 
967 
968  /* Make sure we have a list of devices available at startup. */
969  current_audio.impl.DetectDevices();
970 
971  return 0;
972 }
973 
974 /*
975  * Get the current audio driver name
976  */
977 const char *
979 {
980  return current_audio.name;
981 }
982 
983 /* Clean out devices that we've removed but had to keep around for stability. */
984 static void
985 clean_out_device_list(SDL_AudioDeviceItem **devices, int *devCount, SDL_bool *removedFlag)
986 {
987  SDL_AudioDeviceItem *item = *devices;
988  SDL_AudioDeviceItem *prev = NULL;
989  int total = 0;
990 
991  while (item) {
992  SDL_AudioDeviceItem *next = item->next;
993  if (item->handle != NULL) {
994  total++;
995  prev = item;
996  } else {
997  if (prev) {
998  prev->next = next;
999  } else {
1000  *devices = next;
1001  }
1002  SDL_free(item);
1003  }
1004  item = next;
1005  }
1006 
1007  *devCount = total;
1008  *removedFlag = SDL_FALSE;
1009 }
1010 
1011 
1012 int
1014 {
1015  int retval = 0;
1016 
1017  if (!SDL_WasInit(SDL_INIT_AUDIO)) {
1018  return -1;
1019  }
1020 
1021  SDL_LockMutex(current_audio.detectionLock);
1022  if (iscapture && current_audio.captureDevicesRemoved) {
1023  clean_out_device_list(&current_audio.inputDevices, &current_audio.inputDeviceCount, &current_audio.captureDevicesRemoved);
1024  }
1025 
1026  if (!iscapture && current_audio.outputDevicesRemoved) {
1027  clean_out_device_list(&current_audio.outputDevices, &current_audio.outputDeviceCount, &current_audio.outputDevicesRemoved);
1028  current_audio.outputDevicesRemoved = SDL_FALSE;
1029  }
1030 
1031  retval = iscapture ? current_audio.inputDeviceCount : current_audio.outputDeviceCount;
1032  SDL_UnlockMutex(current_audio.detectionLock);
1033 
1034  return retval;
1035 }
1036 
1037 
1038 const char *
1039 SDL_GetAudioDeviceName(int index, int iscapture)
1040 {
1041  const char *retval = NULL;
1042 
1043  if (!SDL_WasInit(SDL_INIT_AUDIO)) {
1044  SDL_SetError("Audio subsystem is not initialized");
1045  return NULL;
1046  }
1047 
1048  if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) {
1049  SDL_SetError("No capture support");
1050  return NULL;
1051  }
1052 
1053  if (index >= 0) {
1054  SDL_AudioDeviceItem *item;
1055  int i;
1056 
1057  SDL_LockMutex(current_audio.detectionLock);
1058  item = iscapture ? current_audio.inputDevices : current_audio.outputDevices;
1059  i = iscapture ? current_audio.inputDeviceCount : current_audio.outputDeviceCount;
1060  if (index < i) {
1061  for (i--; i > index; i--, item = item->next) {
1062  SDL_assert(item != NULL);
1063  }
1064  SDL_assert(item != NULL);
1065  retval = item->name;
1066  }
1067  SDL_UnlockMutex(current_audio.detectionLock);
1068  }
1069 
1070  if (retval == NULL) {
1071  SDL_SetError("No such device");
1072  }
1073 
1074  return retval;
1075 }
1076 
1077 
1078 static void
1080 {
1081  if (!device) {
1082  return;
1083  }
1084 
1085  if (device->id > 0) {
1086  SDL_AudioDevice *opendev = open_devices[device->id - 1];
1087  SDL_assert((opendev == device) || (opendev == NULL));
1088  if (opendev == device) {
1089  open_devices[device->id - 1] = NULL;
1090  }
1091  }
1092 
1093  SDL_AtomicSet(&device->shutdown, 1);
1094  SDL_AtomicSet(&device->enabled, 0);
1095  if (device->thread != NULL) {
1096  SDL_WaitThread(device->thread, NULL);
1097  }
1098  if (device->mixer_lock != NULL) {
1099  SDL_DestroyMutex(device->mixer_lock);
1100  }
1101  SDL_free(device->fake_stream);
1102  if (device->convert.needed) {
1103  SDL_free(device->convert.buf);
1104  }
1105  if (device->hidden != NULL) {
1106  current_audio.impl.CloseDevice(device);
1107  }
1108 
1111 
1112  SDL_free(device);
1113 }
1114 
1115 
1116 /*
1117  * Sanity check desired AudioSpec for SDL_OpenAudio() in (orig).
1118  * Fills in a sanitized copy in (prepared).
1119  * Returns non-zero if okay, zero on fatal parameters in (orig).
1120  */
1121 static int
1123 {
1124  SDL_memcpy(prepared, orig, sizeof(SDL_AudioSpec));
1125 
1126  if (orig->freq == 0) {
1127  const char *env = SDL_getenv("SDL_AUDIO_FREQUENCY");
1128  if ((!env) || ((prepared->freq = SDL_atoi(env)) == 0)) {
1129  prepared->freq = 22050; /* a reasonable default */
1130  }
1131  }
1132 
1133  if (orig->format == 0) {
1134  const char *env = SDL_getenv("SDL_AUDIO_FORMAT");
1135  if ((!env) || ((prepared->format = SDL_ParseAudioFormat(env)) == 0)) {
1136  prepared->format = AUDIO_S16; /* a reasonable default */
1137  }
1138  }
1139 
1140  switch (orig->channels) {
1141  case 0:{
1142  const char *env = SDL_getenv("SDL_AUDIO_CHANNELS");
1143  if ((!env) || ((prepared->channels = (Uint8) SDL_atoi(env)) == 0)) {
1144  prepared->channels = 2; /* a reasonable default */
1145  }
1146  break;
1147  }
1148  case 1: /* Mono */
1149  case 2: /* Stereo */
1150  case 4: /* surround */
1151  case 6: /* surround with center and lfe */
1152  break;
1153  default:
1154  SDL_SetError("Unsupported number of audio channels.");
1155  return 0;
1156  }
1157 
1158  if (orig->samples == 0) {
1159  const char *env = SDL_getenv("SDL_AUDIO_SAMPLES");
1160  if ((!env) || ((prepared->samples = (Uint16) SDL_atoi(env)) == 0)) {
1161  /* Pick a default of ~46 ms at desired frequency */
1162  /* !!! FIXME: remove this when the non-Po2 resampling is in. */
1163  const int samples = (prepared->freq / 1000) * 46;
1164  int power2 = 1;
1165  while (power2 < samples) {
1166  power2 *= 2;
1167  }
1168  prepared->samples = power2;
1169  }
1170  }
1171 
1172  /* Calculate the silence and size of the audio specification */
1173  SDL_CalculateAudioSpec(prepared);
1174 
1175  return 1;
1176 }
1177 
1178 static SDL_AudioDeviceID
1179 open_audio_device(const char *devname, int iscapture,
1180  const SDL_AudioSpec * desired, SDL_AudioSpec * obtained,
1181  int allowed_changes, int min_id)
1182 {
1183  const SDL_bool is_internal_thread = (desired->callback != NULL);
1184  SDL_AudioDeviceID id = 0;
1185  SDL_AudioSpec _obtained;
1186  SDL_AudioDevice *device;
1187  SDL_bool build_cvt;
1188  void *handle = NULL;
1189  int i = 0;
1190 
1191  if (!SDL_WasInit(SDL_INIT_AUDIO)) {
1192  SDL_SetError("Audio subsystem is not initialized");
1193  return 0;
1194  }
1195 
1196  if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) {
1197  SDL_SetError("No capture support");
1198  return 0;
1199  }
1200 
1201  /* !!! FIXME: there is a race condition here if two devices open from two threads at once. */
1202  /* Find an available device ID... */
1203  for (id = min_id - 1; id < SDL_arraysize(open_devices); id++) {
1204  if (open_devices[id] == NULL) {
1205  break;
1206  }
1207  }
1208 
1209  if (id == SDL_arraysize(open_devices)) {
1210  SDL_SetError("Too many open audio devices");
1211  return 0;
1212  }
1213 
1214  if (!obtained) {
1215  obtained = &_obtained;
1216  }
1217  if (!prepare_audiospec(desired, obtained)) {
1218  return 0;
1219  }
1220 
1221  /* If app doesn't care about a specific device, let the user override. */
1222  if (devname == NULL) {
1223  devname = SDL_getenv("SDL_AUDIO_DEVICE_NAME");
1224  }
1225 
1226  /*
1227  * Catch device names at the high level for the simple case...
1228  * This lets us have a basic "device enumeration" for systems that
1229  * don't have multiple devices, but makes sure the device name is
1230  * always NULL when it hits the low level.
1231  *
1232  * Also make sure that the simple case prevents multiple simultaneous
1233  * opens of the default system device.
1234  */
1235 
1236  if ((iscapture) && (current_audio.impl.OnlyHasDefaultCaptureDevice)) {
1237  if ((devname) && (SDL_strcmp(devname, DEFAULT_INPUT_DEVNAME) != 0)) {
1238  SDL_SetError("No such device");
1239  return 0;
1240  }
1241  devname = NULL;
1242 
1243  for (i = 0; i < SDL_arraysize(open_devices); i++) {
1244  if ((open_devices[i]) && (open_devices[i]->iscapture)) {
1245  SDL_SetError("Audio device already open");
1246  return 0;
1247  }
1248  }
1249  } else if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) {
1250  if ((devname) && (SDL_strcmp(devname, DEFAULT_OUTPUT_DEVNAME) != 0)) {
1251  SDL_SetError("No such device");
1252  return 0;
1253  }
1254  devname = NULL;
1255 
1256  for (i = 0; i < SDL_arraysize(open_devices); i++) {
1257  if ((open_devices[i]) && (!open_devices[i]->iscapture)) {
1258  SDL_SetError("Audio device already open");
1259  return 0;
1260  }
1261  }
1262  } else if (devname != NULL) {
1263  /* if the app specifies an exact string, we can pass the backend
1264  an actual device handle thingey, which saves them the effort of
1265  figuring out what device this was (such as, reenumerating
1266  everything again to find the matching human-readable name).
1267  It might still need to open a device based on the string for,
1268  say, a network audio server, but this optimizes some cases. */
1269  SDL_AudioDeviceItem *item;
1270  SDL_LockMutex(current_audio.detectionLock);
1271  for (item = iscapture ? current_audio.inputDevices : current_audio.outputDevices; item; item = item->next) {
1272  if ((item->handle != NULL) && (SDL_strcmp(item->name, devname) == 0)) {
1273  handle = item->handle;
1274  break;
1275  }
1276  }
1277  SDL_UnlockMutex(current_audio.detectionLock);
1278  }
1279 
1280  if (!current_audio.impl.AllowsArbitraryDeviceNames) {
1281  /* has to be in our device list, or the default device. */
1282  if ((handle == NULL) && (devname != NULL)) {
1283  SDL_SetError("No such device.");
1284  return 0;
1285  }
1286  }
1287 
1288  device = (SDL_AudioDevice *) SDL_calloc(1, sizeof (SDL_AudioDevice));
1289  if (device == NULL) {
1290  SDL_OutOfMemory();
1291  return 0;
1292  }
1293  device->id = id + 1;
1294  device->spec = *obtained;
1295  device->iscapture = iscapture ? SDL_TRUE : SDL_FALSE;
1296  device->handle = handle;
1297 
1298  SDL_AtomicSet(&device->shutdown, 0); /* just in case. */
1299  SDL_AtomicSet(&device->paused, 1);
1300  SDL_AtomicSet(&device->enabled, 1);
1301 
1302  /* Create a mutex for locking the sound buffers */
1303  if (!current_audio.impl.SkipMixerLock) {
1304  device->mixer_lock = SDL_CreateMutex();
1305  if (device->mixer_lock == NULL) {
1306  close_audio_device(device);
1307  SDL_SetError("Couldn't create mixer lock");
1308  return 0;
1309  }
1310  }
1311 
1312  if (current_audio.impl.OpenDevice(device, handle, devname, iscapture) < 0) {
1313  close_audio_device(device);
1314  return 0;
1315  }
1316 
1317  /* if your target really doesn't need it, set it to 0x1 or something. */
1318  /* otherwise, close_audio_device() won't call impl.CloseDevice(). */
1319  SDL_assert(device->hidden != NULL);
1320 
1321  /* See if we need to do any conversion */
1322  build_cvt = SDL_FALSE;
1323  if (obtained->freq != device->spec.freq) {
1324  if (allowed_changes & SDL_AUDIO_ALLOW_FREQUENCY_CHANGE) {
1325  obtained->freq = device->spec.freq;
1326  } else {
1327  build_cvt = SDL_TRUE;
1328  }
1329  }
1330  if (obtained->format != device->spec.format) {
1331  if (allowed_changes & SDL_AUDIO_ALLOW_FORMAT_CHANGE) {
1332  obtained->format = device->spec.format;
1333  } else {
1334  build_cvt = SDL_TRUE;
1335  }
1336  }
1337  if (obtained->channels != device->spec.channels) {
1338  if (allowed_changes & SDL_AUDIO_ALLOW_CHANNELS_CHANGE) {
1339  obtained->channels = device->spec.channels;
1340  } else {
1341  build_cvt = SDL_TRUE;
1342  }
1343  }
1344 
1345  /* If the audio driver changes the buffer size, accept it.
1346  This needs to be done after the format is modified above,
1347  otherwise it might not have the correct buffer size.
1348  */
1349  if (device->spec.samples != obtained->samples) {
1350  obtained->samples = device->spec.samples;
1351  SDL_CalculateAudioSpec(obtained);
1352  }
1353 
1354  if (build_cvt) {
1355  /* Build an audio conversion block */
1356  if (SDL_BuildAudioCVT(&device->convert,
1357  obtained->format, obtained->channels,
1358  obtained->freq,
1359  device->spec.format, device->spec.channels,
1360  device->spec.freq) < 0) {
1361  close_audio_device(device);
1362  return 0;
1363  }
1364  if (device->convert.needed) {
1365  device->convert.len = (int) (((double) device->spec.size) /
1366  device->convert.len_ratio);
1367 
1368  device->convert.buf =
1369  (Uint8 *) SDL_malloc(device->convert.len *
1370  device->convert.len_mult);
1371  if (device->convert.buf == NULL) {
1372  close_audio_device(device);
1373  SDL_OutOfMemory();
1374  return 0;
1375  }
1376  }
1377  }
1378 
1379  if (device->spec.callback == NULL) { /* use buffer queueing? */
1380  /* pool a few packets to start. Enough for two callbacks. */
1381  const int packetlen = SDL_AUDIOBUFFERQUEUE_PACKETLEN;
1382  const int wantbytes = ((device->convert.needed) ? device->convert.len : device->spec.size) * 2;
1383  const int wantpackets = (wantbytes / packetlen) + ((wantbytes % packetlen) ? packetlen : 0);
1384  for (i = 0; i < wantpackets; i++) {
1386  if (packet) { /* don't care if this fails, we'll deal later. */
1387  packet->datalen = 0;
1388  packet->startpos = 0;
1389  packet->next = device->buffer_queue_pool;
1390  device->buffer_queue_pool = packet;
1391  }
1392  }
1393 
1395  device->spec.userdata = device;
1396  }
1397 
1398  /* add it to our list of open devices. */
1399  open_devices[id] = device;
1400 
1401  /* Start the audio thread if necessary */
1402  if (!current_audio.impl.ProvidesOwnCallbackThread) {
1403  /* Start the audio thread */
1404  /* !!! FIXME: we don't force the audio thread stack size here if it calls into user code, but maybe we should? */
1405  /* buffer queueing callback only needs a few bytes, so make the stack tiny. */
1406  const size_t stacksize = is_internal_thread ? 64 * 1024 : 0;
1407  char threadname[64];
1408 
1409  /* Allocate a fake audio buffer; only used by our internal threads. */
1410  Uint32 stream_len = (device->convert.needed) ? device->convert.len_cvt : 0;
1411  if (device->spec.size > stream_len) {
1412  stream_len = device->spec.size;
1413  }
1414  SDL_assert(stream_len > 0);
1415 
1416  device->fake_stream = (Uint8 *) SDL_malloc(stream_len);
1417  if (device->fake_stream == NULL) {
1418  close_audio_device(device);
1419  SDL_OutOfMemory();
1420  return 0;
1421  }
1422 
1423  SDL_snprintf(threadname, sizeof (threadname), "SDLAudioDev%d", (int) device->id);
1424  device->thread = SDL_CreateThreadInternal(iscapture ? SDL_CaptureAudio : SDL_RunAudio, threadname, stacksize, device);
1425 
1426  if (device->thread == NULL) {
1427  close_audio_device(device);
1428  SDL_SetError("Couldn't create audio thread");
1429  return 0;
1430  }
1431  }
1432 
1433  return device->id;
1434 }
1435 
1436 
1437 int
1439 {
1440  SDL_AudioDeviceID id = 0;
1441 
1442  /* Start up the audio driver, if necessary. This is legacy behaviour! */
1443  if (!SDL_WasInit(SDL_INIT_AUDIO)) {
1444  if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) {
1445  return -1;
1446  }
1447  }
1448 
1449  /* SDL_OpenAudio() is legacy and can only act on Device ID #1. */
1450  if (open_devices[0] != NULL) {
1451  SDL_SetError("Audio device is already opened");
1452  return -1;
1453  }
1454 
1455  if (obtained) {
1456  id = open_audio_device(NULL, 0, desired, obtained,
1458  } else {
1459  id = open_audio_device(NULL, 0, desired, NULL, 0, 1);
1460  }
1461 
1462  SDL_assert((id == 0) || (id == 1));
1463  return (id == 0) ? -1 : 0;
1464 }
1465 
1467 SDL_OpenAudioDevice(const char *device, int iscapture,
1468  const SDL_AudioSpec * desired, SDL_AudioSpec * obtained,
1469  int allowed_changes)
1470 {
1471  return open_audio_device(device, iscapture, desired, obtained,
1472  allowed_changes, 2);
1473 }
1474 
1477 {
1478  SDL_AudioDevice *device = get_audio_device(devid);
1480  if (device && SDL_AtomicGet(&device->enabled)) {
1481  if (SDL_AtomicGet(&device->paused)) {
1482  status = SDL_AUDIO_PAUSED;
1483  } else {
1484  status = SDL_AUDIO_PLAYING;
1485  }
1486  }
1487  return status;
1488 }
1489 
1490 
1493 {
1494  return SDL_GetAudioDeviceStatus(1);
1495 }
1496 
1497 void
1499 {
1500  SDL_AudioDevice *device = get_audio_device(devid);
1501  if (device) {
1502  current_audio.impl.LockDevice(device);
1503  SDL_AtomicSet(&device->paused, pause_on ? 1 : 0);
1504  current_audio.impl.UnlockDevice(device);
1505  }
1506 }
1507 
1508 void
1509 SDL_PauseAudio(int pause_on)
1510 {
1511  SDL_PauseAudioDevice(1, pause_on);
1512 }
1513 
1514 
1515 void
1517 {
1518  /* Obtain a lock on the mixing buffers */
1519  SDL_AudioDevice *device = get_audio_device(devid);
1520  if (device) {
1521  current_audio.impl.LockDevice(device);
1522  }
1523 }
1524 
1525 void
1527 {
1529 }
1530 
1531 void
1533 {
1534  /* Obtain a lock on the mixing buffers */
1535  SDL_AudioDevice *device = get_audio_device(devid);
1536  if (device) {
1537  current_audio.impl.UnlockDevice(device);
1538  }
1539 }
1540 
1541 void
1543 {
1545 }
1546 
1547 void
1549 {
1551 }
1552 
1553 void
1555 {
1557 }
1558 
1559 void
1561 {
1563 
1564  if (!current_audio.name) { /* not initialized?! */
1565  return;
1566  }
1567 
1568  for (i = 0; i < SDL_arraysize(open_devices); i++) {
1569  close_audio_device(open_devices[i]);
1570  }
1571 
1572  free_device_list(&current_audio.outputDevices, &current_audio.outputDeviceCount);
1573  free_device_list(&current_audio.inputDevices, &current_audio.inputDeviceCount);
1574 
1575  /* Free the driver data */
1576  current_audio.impl.Deinitialize();
1577 
1578  SDL_DestroyMutex(current_audio.detectionLock);
1579 
1580  SDL_zero(current_audio);
1581  SDL_zero(open_devices);
1582 }
1583 
1584 #define NUM_FORMATS 10
1585 static int format_idx;
1586 static int format_idx_sub;
1608 };
1609 
1612 {
1613  for (format_idx = 0; format_idx < NUM_FORMATS; ++format_idx) {
1614  if (format_list[format_idx][0] == format) {
1615  break;
1616  }
1617  }
1618  format_idx_sub = 0;
1619  return SDL_NextAudioFormat();
1620 }
1621 
1624 {
1625  if ((format_idx == NUM_FORMATS) || (format_idx_sub == NUM_FORMATS)) {
1626  return 0;
1627  }
1629 }
1630 
1631 void
1633 {
1634  switch (spec->format) {
1635  case AUDIO_U8:
1636  spec->silence = 0x80;
1637  break;
1638  default:
1639  spec->silence = 0x00;
1640  break;
1641  }
1642  spec->size = SDL_AUDIO_BITSIZE(spec->format) / 8;
1643  spec->size *= spec->channels;
1644  spec->size *= spec->samples;
1645 }
1646 
1647 
1648 /*
1649  * Moved here from SDL_mixer.c, since it relies on internals of an opened
1650  * audio device (and is deprecated, by the way!).
1651  */
1652 void
1653 SDL_MixAudio(Uint8 * dst, const Uint8 * src, Uint32 len, int volume)
1654 {
1655  /* Mix the user-level audio format */
1656  SDL_AudioDevice *device = get_audio_device(1);
1657  if (device != NULL) {
1659  if (device->convert.needed) {
1660  format = device->convert.src_format;
1661  } else {
1662  format = device->spec.format;
1663  }
1664  SDL_MixAudioFormat(dst, src, format, len, volume);
1665  }
1666 }
1667 
1668 /* vi: set ts=4 sw=4 expandtab: */
static SDL_AudioDevice * open_devices[16]
Definition: SDL_audio.c:34
#define SDL_ThreadID
struct SDL_PrivateAudioData * hidden
Definition: SDL_sysaudio.h:189
static int format_idx_sub
Definition: SDL_audio.c:1586
void SDL_LockAudioDevice(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:1516
#define SDL_strlcpy
GLenum GLenum dst
static int queue_audio_to_device(SDL_AudioDevice *device, const Uint8 *data, Uint32 len)
Definition: SDL_audio.c:464
SDL_AudioDeviceID id
Definition: SDL_sysaudio.h:153
#define SDL_AUDIO_ALLOW_FREQUENCY_CHANGE
Definition: SDL_audio.h:140
void SDL_UnlockAudio(void)
Definition: SDL_audio.c:1542
#define SDL_LockMutex
GLint GLint GLsizei GLsizei GLsizei GLint GLenum format
Definition: SDL_opengl.h:1565
GLuint id
static int SDL_CaptureAudio(void *devicep)
Definition: SDL_audio.c:795
AudioBootStrap PSPAUDIO_bootstrap
AudioBootStrap SUNAUDIO_bootstrap
static int format_idx
Definition: SDL_audio.c:1585
GLuint GLfloat GLfloat GLfloat x1
SDL_mutex * mixer_lock
Definition: SDL_sysaudio.h:175
#define SDL_min(x, y)
Definition: SDL_stdinc.h:349
SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format)
Definition: SDL_audio.c:1611
#define AUDIO_S32MSB
Definition: SDL_audio.h:104
SDL_bool captureDevicesRemoved
Definition: SDL_sysaudio.h:130
SDL_atomic_t enabled
Definition: SDL_sysaudio.h:167
#define S32
AudioBootStrap PULSEAUDIO_bootstrap
const char * name
Definition: SDL_sysaudio.h:120
void(* DetectDevices)(void)
Definition: SDL_sysaudio.h:75
int SDL_GetNumAudioDrivers(void)
Definition: SDL_audio.c:902
Uint8 silence
Definition: SDL_audio.h:173
int SDL_OpenAudio(SDL_AudioSpec *desired, SDL_AudioSpec *obtained)
Definition: SDL_audio.c:1438
const char * SDL_GetCurrentAudioDriver()
Definition: SDL_audio.c:978
const char * name
Definition: SDL_sysaudio.h:197
static void mark_device_removed(void *handle, SDL_AudioDeviceItem *devices, SDL_bool *removedFlag)
Definition: SDL_audio.c:407
#define AUDIO_U16LSB
Definition: SDL_audio.h:91
Uint8 * buf
Definition: SDL_audio.h:206
GLuint GLuint stream
const char * SDL_GetAudioDriver(int index)
Definition: SDL_audio.c:908
#define SDL_BuildAudioCVT
struct SDL_AudioDeviceItem * next
Definition: SDL_sysaudio.h:107
static void clean_out_device_list(SDL_AudioDeviceItem **devices, int *devCount, SDL_bool *removedFlag)
Definition: SDL_audio.c:985
AudioBootStrap QSAAUDIO_bootstrap
SDL_atomic_t paused
Definition: SDL_sysaudio.h:168
static SDL_INLINE int add_output_device(const char *name, void *handle)
Definition: SDL_audio.c:341
#define SDL_CreateMutex
SDL_atomic_t shutdown
Definition: SDL_sysaudio.h:166
static SDL_AudioFormat format_list[NUM_FORMATS][NUM_FORMATS]
Definition: SDL_audio.c:1587
double len_ratio
Definition: SDL_audio.h:210
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1967
SDL_AudioStatus
Definition: SDL_audio.h:369
SDL_AudioDeviceID SDL_OpenAudioDevice(const char *device, int iscapture, const SDL_AudioSpec *desired, SDL_AudioSpec *obtained, int allowed_changes)
Definition: SDL_audio.c:1467
SDL_threadID threadid
Definition: SDL_sysaudio.h:179
#define SDL_ENABLE
Definition: SDL_events.h:722
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:79
SDL_AudioBufferQueue * buffer_queue_pool
Definition: SDL_sysaudio.h:184
Uint16 samples
Definition: SDL_audio.h:174
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:78
void SDL_ClearQueuedAudio(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:668
void SDL_OpenedAudioDeviceDisconnected(SDL_AudioDevice *device)
Definition: SDL_audio.c:381
#define SDL_InitSubSystem
static int SDL_RunAudio(void *devicep)
Definition: SDL_audio.c:714
#define SDL_MixAudioFormat
SDL_AudioSpec spec
Definition: SDL_sysaudio.h:156
Uint16 SDL_AudioFormat
Audio format flags.
Definition: SDL_audio.h:64
Uint32 SDL_GetQueuedAudioSize(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:644
static Uint8 * SDL_AudioGetDeviceBuf_Default(_THIS)
Definition: SDL_audio.c:189
GLuint const GLchar * name
AudioBootStrap DSOUND_bootstrap
static void SDL_AudioUnlockDevice_Default(SDL_AudioDevice *device)
Definition: SDL_audio.c:255
uint32_t Uint32
An unsigned 32-bit integer type.
Definition: SDL_stdinc.h:159
static SDL_AudioDriver current_audio
Definition: SDL_audio.c:33
void(* UnlockDevice)(_THIS)
Definition: SDL_sysaudio.h:87
AudioBootStrap ARTS_bootstrap
#define SDL_strncasecmp
AudioBootStrap WINMM_bootstrap
GLsizeiptr size
AudioBootStrap BSD_AUDIO_bootstrap
GLfixed GLfixed x2
GLenum GLsizei len
SDL_AudioFormat SDL_NextAudioFormat(void)
Definition: SDL_audio.c:1623
#define SDL_AUDIO_ALLOW_CHANNELS_CHANGE
Definition: SDL_audio.h:142
#define FILL_STUB(x)
#define AUDIO_F32MSB
Definition: SDL_audio.h:113
SDL_mutex * detectionLock
Definition: SDL_sysaudio.h:129
SDL_AudioBufferQueue * buffer_queue_head
Definition: SDL_sysaudio.h:182
SDL_AudioSpec spec
Definition: loopwave.c:35
SDL_bool retval
AudioBootStrap ANDROIDAUDIO_bootstrap
#define AUDIO_U8
Definition: SDL_audio.h:89
void SDL_LockAudio(void)
Definition: SDL_audio.c:1526
SDL_AudioBufferQueue * buffer_queue_tail
Definition: SDL_sysaudio.h:183
#define SDL_memcpy
SDL_Thread * SDL_CreateThreadInternal(int(*fn)(void *), const char *name, const size_t stacksize, void *data)
Definition: SDL_thread.c:427
void * SDL_calloc(size_t nmemb, size_t size)
static void SDL_AudioDeinitialize_Default(void)
Definition: SDL_audio.c:216
struct SDL_AudioBufferQueue * next
Definition: SDL_sysaudio.h:70
void(* ThreadInit)(_THIS)
Definition: SDL_sysaudio.h:77
SDL_AudioStatus SDL_GetAudioDeviceStatus(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:1476
#define SDL_GetEventState(type)
Definition: SDL_events.h:735
#define SDL_ConvertAudio
void SDL_RemoveAudioDevice(const int iscapture, void *handle)
Definition: SDL_audio.c:422
Uint8 channels
Definition: SDL_audio.h:172
#define _THIS
Definition: SDL_audio.c:31
uint8_t Uint8
An unsigned 8-bit integer type.
Definition: SDL_stdinc.h:143
const char * desc
Definition: SDL_sysaudio.h:124
struct _cl_event * event
static void SDL_AudioWaitDevice_Default(_THIS)
Definition: SDL_audio.c:173
static void SDL_AudioLockOrUnlockDeviceWithNoMixerLock(SDL_AudioDevice *device)
Definition: SDL_audio.c:263
void SDL_free(void *mem)
AudioBootStrap DISKAUDIO_bootstrap
#define SDL_AUDIO_BITSIZE(x)
Definition: SDL_audio.h:75
#define AUDIO_F32LSB
Definition: SDL_audio.h:112
void(* PrepareToClose)(_THIS)
Definition: SDL_sysaudio.h:84
SDL_bool iscapture
Definition: SDL_sysaudio.h:169
AudioBootStrap PAUDIO_bootstrap
void SDL_AudioQuit(void)
Definition: SDL_audio.c:1560
#define SDL_AUDIO_ALLOW_ANY_CHANGE
Definition: SDL_audio.h:143
#define SDL_PushEvent
void(* Deinitialize)(void)
Definition: SDL_sysaudio.h:89
static int prepare_audiospec(const SDL_AudioSpec *orig, SDL_AudioSpec *prepared)
Definition: SDL_audio.c:1122
void SDL_UnlockAudioDevice(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:1532
static int SDL_AudioOpenDevice_Default(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_audio.c:227
static Uint32 dequeue_audio_from_device(SDL_AudioDevice *device, Uint8 *stream, Uint32 len)
Definition: SDL_audio.c:531
AudioBootStrap COREAUDIO_bootstrap
#define AUDIO_S32LSB
Definition: SDL_audio.h:103
#define SDL_zero(x)
Definition: SDL_stdinc.h:359
static Uint32 callback(Uint32 interval, void *param)
Definition: testtimer.c:34
void SDL_PauseAudio(int pause_on)
Definition: SDL_audio.c:1509
#define NUM_FORMATS
Definition: SDL_audio.c:1584
AudioBootStrap ALSA_bootstrap
void SDL_CalculateAudioSpec(SDL_AudioSpec *spec)
Definition: SDL_audio.c:1632
GLsizei samples
SDL_AudioStatus SDL_GetAudioStatus(void)
Definition: SDL_audio.c:1492
SDL_AudioCallback callback
Definition: SDL_audio.h:177
SDL_AudioFormat src_format
Definition: SDL_audio.h:203
static void SDL_AudioThreadInit_Default(_THIS)
Definition: SDL_audio.c:168
static void SDL_AudioDetectDevices_Default(void)
Definition: SDL_audio.c:155
static int SDL_AudioCaptureFromDevice_Default(_THIS, void *buffer, int buflen)
Definition: SDL_audio.c:195
Uint8 * fake_stream
Definition: SDL_sysaudio.h:172
#define SDL_atoi
GLuint index
int SDL_QueueAudio(SDL_AudioDeviceID devid, const void *data, Uint32 len)
Definition: SDL_audio.c:602
static int add_audio_device(const char *name, void *handle, SDL_AudioDeviceItem **devices, int *devCount)
Definition: SDL_audio.c:310
AudioBootStrap NAS_bootstrap
void(* LockDevice)(_THIS)
Definition: SDL_sysaudio.h:86
const char * SDL_GetAudioDeviceName(int index, int iscapture)
Definition: SDL_audio.c:1039
#define SDL_Delay
static void SDL_BufferQueueDrainCallback(void *userdata, Uint8 *stream, int len)
Definition: SDL_audio.c:565
#define SDL_getenv
SDL_AudioDeviceItem * outputDevices
Definition: SDL_sysaudio.h:134
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
Uint32 size
Definition: SDL_audio.h:176
static int SDL_AudioGetPendingBytes_Default(_THIS)
Definition: SDL_audio.c:183
#define SDL_assert(condition)
Definition: SDL_assert.h:167
static const AudioBootStrap *const bootstrap[]
Definition: SDL_audio.c:67
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:76
static void SDL_AudioPlayDevice_Default(_THIS)
Definition: SDL_audio.c:178
#define NULL
Definition: begin_code.h:143
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_bool
Definition: SDL_stdinc.h:130
SDL_bool outputDevicesRemoved
Definition: SDL_sysaudio.h:131
int(* CaptureFromDevice)(_THIS, void *buffer, int buflen)
Definition: SDL_sysaudio.h:82
static void free_device_list(SDL_AudioDeviceItem **devices, int *devCount)
Definition: SDL_audio.c:347
AudioBootStrap DSP_bootstrap
static void SDL_BufferQueueFillCallback(void *userdata, Uint8 *stream, int len)
Definition: SDL_audio.c:586
#define SDL_SetError
static SDL_AudioDeviceID open_audio_device(const char *devname, int iscapture, const SDL_AudioSpec *desired, SDL_AudioSpec *obtained, int allowed_changes, int min_id)
Definition: SDL_audio.c:1179
AudioBootStrap DUMMYAUDIO_bootstrap
SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char const char SDL_SCANF_FORMAT_STRING const char return SDL_ThreadFunction const char void return Uint32 return Uint32 void
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:85
#define SDL_DestroyMutex
static SDL_INLINE int add_capture_device(const char *name, void *handle)
Definition: SDL_audio.c:334
#define SDL_INIT_AUDIO
Definition: SDL.h:76
static void free_audio_queue(SDL_AudioBufferQueue *packet)
Definition: SDL_audio.c:453
#define AUDIO_S16MSB
Definition: SDL_audio.h:94
static void SDL_AudioLockDevice_Default(SDL_AudioDevice *device)
Definition: SDL_audio.c:247
AudioBootStrap NACLAUDIO_bootstrap
SDL_AudioDriverImpl impl
Definition: SDL_sysaudio.h:126
void(* FreeDeviceHandle)(void *handle)
Definition: SDL_sysaudio.h:88
#define SDL_strlen
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:304
SDL_AudioFormat format
Definition: SDL_audio.h:171
void(* FlushCapture)(_THIS)
Definition: SDL_sysaudio.h:83
AudioBootStrap XAUDIO2_bootstrap
AudioBootStrap HAIKUAUDIO_bootstrap
GLuint buffer
#define AUDIO_S16
Definition: SDL_audio.h:96
#define AUDIO_S16LSB
Definition: SDL_audio.h:92
void SDL_CloseAudio(void)
Definition: SDL_audio.c:1554
Uint8 *(* GetDeviceBuf)(_THIS)
Definition: SDL_sysaudio.h:81
#define SDL_AtomicSet
int SDL_GetNumAudioDevices(int iscapture)
Definition: SDL_audio.c:1013
AudioBootStrap EMSCRIPTENAUDIO_bootstrap
#define SDL_AtomicGet
uint16_t Uint16
An unsigned 16-bit integer type.
Definition: SDL_stdinc.h:151
void * userdata
Definition: SDL_audio.h:178
#define DEFAULT_OUTPUT_DEVNAME
Definition: SDL_sysaudio.h:30
#define SDL_AUDIO_ALLOW_FORMAT_CHANGE
Definition: SDL_audio.h:141
#define SDL_snprintf
static SDL_AudioFormat SDL_ParseAudioFormat(const char *string)
Definition: SDL_audio.c:876
#define DEFAULT_INPUT_DEVNAME
Definition: SDL_sysaudio.h:31
#define SDL_UnlockMutex
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:90
Uint8 data[SDL_AUDIOBUFFERQUEUE_PACKETLEN]
Definition: SDL_sysaudio.h:67
static void SDL_AudioPrepareToClose_Default(_THIS)
Definition: SDL_audio.c:206
#define SDL_INLINE
Definition: begin_code.h:120
General event structure.
Definition: SDL_events.h:525
#define SDL_malloc
int(* init)(SDL_AudioDriverImpl *impl)
Definition: SDL_sysaudio.h:199
static void SDL_AudioCloseDevice_Default(_THIS)
Definition: SDL_audio.c:211
int(* GetPendingBytes)(_THIS)
Definition: SDL_sysaudio.h:80
#define SDL_strcmp
const char * desc
Definition: SDL_sysaudio.h:198
AudioBootStrap ESD_bootstrap
SDL_Thread * thread
Definition: SDL_sysaudio.h:178
Uint32 SDL_DequeueAudio(SDL_AudioDeviceID devid, void *data, Uint32 len)
Definition: SDL_audio.c:625
#define SDL_WasInit
void SDL_CloseAudioDevice(SDL_AudioDeviceID devid)
Definition: SDL_audio.c:1548
#define SDL_AUDIOBUFFERQUEUE_PACKETLEN
Definition: SDL_sysaudio.h:62
static void SDL_AudioFlushCapture_Default(_THIS)
Definition: SDL_audio.c:201
SDL_AudioCVT convert
Definition: SDL_sysaudio.h:159
#define AUDIO_S8
Definition: SDL_audio.h:90
void SDL_MixAudio(Uint8 *dst, const Uint8 *src, Uint32 len, int volume)
Definition: SDL_audio.c:1653
#define CHECK_FMT_STRING(x)
GLenum src
#define SDLCALL
Definition: SDL_internal.h:31
void SDL_PauseAudioDevice(SDL_AudioDeviceID devid, int pause_on)
Definition: SDL_audio.c:1498
static SDL_AudioDevice * get_audio_device(SDL_AudioDeviceID id)
Definition: SDL_audio.c:141
#define SDL_Unsupported()
Definition: SDL_error.h:53
static SDL_INLINE SDL_bool is_in_audio_device_thread(SDL_AudioDevice *device)
Definition: SDL_audio.c:233
#define SDL_SetThreadPriority
static void finish_audio_entry_points_init(void)
Definition: SDL_audio.c:268
SDL_AudioDeviceItem * inputDevices
Definition: SDL_sysaudio.h:135
#define SDL_memset
static void SDL_AudioFreeDeviceHandle_Default(void *handle)
Definition: SDL_audio.c:221
AudioBootStrap SNDIO_bootstrap
Definition: SDL_audio.c:63
int SDL_AudioInit(const char *driver_name)
Definition: SDL_audio.c:917
#define SDL_WaitThread
#define AUDIO_U16MSB
Definition: SDL_audio.h:93
void SDL_AddAudioDevice(const int iscapture, const char *name, void *handle)
Definition: SDL_audio.c:364
static void close_audio_device(SDL_AudioDevice *device)
Definition: SDL_audio.c:1079
AudioBootStrap FUSIONSOUND_bootstrap