This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
/
SDL_audio.c
982 lines (857 loc) · 26.6 KB
1
2
/*
SDL - Simple DirectMedia Layer
3
Copyright (C) 1997-2006 Sam Lantinga
4
5
This library is free software; you can redistribute it and/or
6
modify it under the terms of the GNU Lesser General Public
7
License as published by the Free Software Foundation; either
8
version 2.1 of the License, or (at your option) any later version.
9
10
11
12
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13
Lesser General Public License for more details.
14
15
16
17
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18
19
Sam Lantinga
20
slouken@libsdl.org
21
*/
22
#include "SDL_config.h"
23
24
25
26
27
28
29
30
/* Allow access to a raw mixing buffer */
#include "SDL.h"
#include "SDL_audio_c.h"
#include "SDL_audiomem.h"
#include "SDL_sysaudio.h"
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
#define _THIS SDL_AudioDevice *this
static SDL_AudioDriver current_audio;
static SDL_AudioDevice *open_devices[16];
/* !!! FIXME: These are wordy and unlocalized... */
#define DEFAULT_OUTPUT_DEVNAME "System audio output device"
#define DEFAULT_INPUT_DEVNAME "System audio capture device"
/*
* Not all of these will be compiled and linked in, but it's convenient
* to have a complete list here and saves yet-another block of #ifdefs...
* Please see bootstrap[], below, for the actual #ifdef mess.
*/
extern AudioBootStrap BSD_AUDIO_bootstrap;
extern AudioBootStrap DSP_bootstrap;
extern AudioBootStrap DMA_bootstrap;
extern AudioBootStrap ALSA_bootstrap;
extern AudioBootStrap QNXNTOAUDIO_bootstrap;
extern AudioBootStrap SUNAUDIO_bootstrap;
extern AudioBootStrap DMEDIA_bootstrap;
extern AudioBootStrap ARTS_bootstrap;
extern AudioBootStrap ESD_bootstrap;
extern AudioBootStrap NAS_bootstrap;
extern AudioBootStrap DSOUND_bootstrap;
57
extern AudioBootStrap WINWAVEOUT_bootstrap;
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
extern AudioBootStrap PAUDIO_bootstrap;
extern AudioBootStrap BEOSAUDIO_bootstrap;
extern AudioBootStrap COREAUDIO_bootstrap;
extern AudioBootStrap SNDMGR_bootstrap;
extern AudioBootStrap MINTAUDIO_GSXB_bootstrap;
extern AudioBootStrap MINTAUDIO_MCSN_bootstrap;
extern AudioBootStrap MINTAUDIO_STFA_bootstrap;
extern AudioBootStrap MINTAUDIO_XBIOS_bootstrap;
extern AudioBootStrap MINTAUDIO_DMA8_bootstrap;
extern AudioBootStrap DISKAUD_bootstrap;
extern AudioBootStrap DUMMYAUD_bootstrap;
extern AudioBootStrap DCAUD_bootstrap;
extern AudioBootStrap MMEAUDIO_bootstrap;
extern AudioBootStrap DART_bootstrap;
73
74
75
/* Available audio drivers */
static AudioBootStrap *bootstrap[] = {
76
#if SDL_AUDIO_DRIVER_BSD
77
&BSD_AUDIO_bootstrap,
78
#endif
79
#if SDL_AUDIO_DRIVER_OSS
80
81
&DSP_bootstrap,
&DMA_bootstrap,
82
#endif
83
#if SDL_AUDIO_DRIVER_ALSA
84
&ALSA_bootstrap,
85
#endif
86
#if SDL_AUDIO_DRIVER_QNXNTO
87
&QNXNTOAUDIO_bootstrap,
88
#endif
89
#if SDL_AUDIO_DRIVER_SUNAUDIO
90
&SUNAUDIO_bootstrap,
91
#endif
92
#if SDL_AUDIO_DRIVER_DMEDIA
93
&DMEDIA_bootstrap,
94
#endif
95
#if SDL_AUDIO_DRIVER_ARTS
96
&ARTS_bootstrap,
97
#endif
98
#if SDL_AUDIO_DRIVER_ESD
99
&ESD_bootstrap,
100
#endif
101
#if SDL_AUDIO_DRIVER_NAS
102
&NAS_bootstrap,
103
#endif
104
#if SDL_AUDIO_DRIVER_DSOUND
105
&DSOUND_bootstrap,
106
#endif
107
108
#if SDL_AUDIO_DRIVER_WINWAVEOUT
&WINWAVEOUT_bootstrap,
109
#endif
110
111
#if SDL_AUDIO_DRIVER_PAUDIO
&PAUDIO_bootstrap,
112
#endif
113
114
#if SDL_AUDIO_DRIVER_BEOSAUDIO
&BEOSAUDIO_bootstrap,
115
#endif
116
#if SDL_AUDIO_DRIVER_COREAUDIO
117
&COREAUDIO_bootstrap,
118
#endif
119
#if SDL_AUDIO_DRIVER_SNDMGR
120
&SNDMGR_bootstrap,
121
#endif
122
#if SDL_AUDIO_DRIVER_MINT
123
124
125
126
127
&MINTAUDIO_GSXB_bootstrap,
&MINTAUDIO_MCSN_bootstrap,
&MINTAUDIO_STFA_bootstrap,
&MINTAUDIO_XBIOS_bootstrap,
&MINTAUDIO_DMA8_bootstrap,
128
#endif
129
#if SDL_AUDIO_DRIVER_DISK
130
&DISKAUD_bootstrap,
131
#endif
132
#if SDL_AUDIO_DRIVER_DUMMY
133
&DUMMYAUD_bootstrap,
134
#endif
135
#if SDL_AUDIO_DRIVER_DC
136
&DCAUD_bootstrap,
137
#endif
138
#if SDL_AUDIO_DRIVER_MMEAUDIO
139
&MMEAUDIO_bootstrap,
140
141
#endif
#if SDL_AUDIO_DRIVER_DART
142
&DART_bootstrap,
143
#endif
144
NULL
145
146
};
147
148
static SDL_AudioDevice *
get_audio_device(SDL_AudioDeviceID id)
149
150
{
id--;
151
if ((id >= SDL_arraysize(open_devices)) || (open_devices[id] == NULL)) {
152
153
154
155
156
157
158
159
160
SDL_SetError("Invalid audio device ID");
return NULL;
}
return open_devices[id];
}
/* stubs for audio drivers that don't need a specific entry point... */
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
static int
SDL_AudioDetectDevices_Default(int iscapture)
{
return -1;
}
static void
SDL_AudioThreadInit_Default(_THIS)
{ /* no-op. */
}
static void
SDL_AudioWaitDevice_Default(_THIS)
{ /* no-op. */
}
static void
SDL_AudioPlayDevice_Default(_THIS)
{ /* no-op. */
}
static Uint8 *
SDL_AudioGetDeviceBuf_Default(_THIS)
{
return NULL;
}
static void
SDL_AudioWaitDone_Default(_THIS)
{ /* no-op. */
}
static void
SDL_AudioCloseDevice_Default(_THIS)
{ /* no-op. */
}
static void
SDL_AudioDeinitialize_Default(void)
{ /* no-op. */
}
195
196
197
198
199
200
201
static int
SDL_AudioOpenDevice_Default(_THIS, const char *devname, int iscapture)
{
return 0;
}
202
203
static const char *
SDL_AudioGetDeviceName_Default(int index, int iscapture)
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
{
SDL_SetError("No such device");
return NULL;
}
static void
SDL_AudioLockDevice_Default(SDL_AudioDevice * device)
{
if (device->thread && (SDL_ThreadID() == device->threadid)) {
return;
}
SDL_mutexP(device->mixer_lock);
}
static void
SDL_AudioUnlockDevice_Default(SDL_AudioDevice * device)
{
if (device->thread && (SDL_ThreadID() == device->threadid)) {
return;
}
SDL_mutexV(device->mixer_lock);
}
228
229
static void
finalize_audio_entry_points(void)
230
231
232
233
234
235
{
/*
* Fill in stub functions for unused driver entry points. This lets us
* blindly call them without having to check for validity first.
*/
236
#define FILL_STUB(x) \
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
if (current_audio.impl.x == NULL) { \
current_audio.impl.x = SDL_Audio##x##_Default; \
}
FILL_STUB(DetectDevices);
FILL_STUB(GetDeviceName);
FILL_STUB(OpenDevice);
FILL_STUB(ThreadInit);
FILL_STUB(WaitDevice);
FILL_STUB(PlayDevice);
FILL_STUB(GetDeviceBuf);
FILL_STUB(WaitDone);
FILL_STUB(CloseDevice);
FILL_STUB(LockDevice);
FILL_STUB(UnlockDevice);
FILL_STUB(Deinitialize);
252
#undef FILL_STUB
253
}
254
255
256
/* The general mixing thread function */
257
int SDLCALL
258
SDL_RunAudio(void *devicep)
259
{
260
SDL_AudioDevice *device = (SDL_AudioDevice *) devicep;
261
262
263
264
265
Uint8 *stream;
int stream_len;
void *udata;
void (SDLCALL * fill) (void *userdata, Uint8 * stream, int len);
int silence;
266
267
/* Perform any thread setup */
268
269
device->threadid = SDL_ThreadID();
current_audio.impl.ThreadInit(device);
270
271
/* Set up the mixing function */
272
273
fill = device->spec.callback;
udata = device->spec.userdata;
274
275
276
if (device->convert.needed) {
if (device->convert.src_format == AUDIO_U8) {
277
278
279
280
silence = 0x80;
} else {
silence = 0;
}
281
stream_len = device->convert.len;
282
} else {
283
284
silence = device->spec.silence;
stream_len = device->spec.size;
285
}
286
287
/* Loop, filling the audio buffers */
288
while (device->enabled) {
289
290
/* Fill the current buffer with sound */
291
292
293
if (device->convert.needed) {
if (device->convert.buf) {
stream = device->convert.buf;
294
295
296
297
} else {
continue;
}
} else {
298
stream = current_audio.impl.GetDeviceBuf(device);
299
if (stream == NULL) {
300
stream = device->fake_stream;
301
}
302
}
303
304
305
if (!device->paused) {
SDL_mutexP(device->mixer_lock);
306
(*fill) (udata, stream, stream_len);
307
SDL_mutexV(device->mixer_lock);
308
}
309
310
/* Convert the audio if necessary */
311
312
313
if (device->convert.needed) {
SDL_ConvertAudio(&device->convert);
stream = current_audio.impl.GetDeviceBuf(device);
314
if (stream == NULL) {
315
stream = device->fake_stream;
316
}
317
SDL_memcpy(stream, device->convert.buf, device->convert.len_cvt);
318
319
320
}
/* Ready current buffer for play and change current buffer */
321
322
if (stream != device->fake_stream) {
current_audio.impl.PlayDevice(device);
323
324
325
}
/* Wait for an audio buffer to become available */
326
327
if (stream == device->fake_stream) {
SDL_Delay((device->spec.samples * 1000) / device->spec.freq);
328
} else {
329
current_audio.impl.WaitDevice(device);
330
331
332
333
}
}
/* Wait for the audio to drain.. */
334
current_audio.impl.WaitDone(device);
335
336
return (0);
337
338
}
339
340
static SDL_AudioFormat
341
SDL_ParseAudioFormat(const char *string)
342
{
343
#define CHECK_FMT_STRING(x) if (SDL_strcmp(string, #x) == 0) return AUDIO_##x
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
CHECK_FMT_STRING(U8);
CHECK_FMT_STRING(S8);
CHECK_FMT_STRING(U16LSB);
CHECK_FMT_STRING(S16LSB);
CHECK_FMT_STRING(U16MSB);
CHECK_FMT_STRING(S16MSB);
CHECK_FMT_STRING(U16SYS);
CHECK_FMT_STRING(S16SYS);
CHECK_FMT_STRING(U16);
CHECK_FMT_STRING(S16);
CHECK_FMT_STRING(S32LSB);
CHECK_FMT_STRING(S32MSB);
CHECK_FMT_STRING(S32SYS);
CHECK_FMT_STRING(S32);
CHECK_FMT_STRING(F32LSB);
CHECK_FMT_STRING(F32MSB);
CHECK_FMT_STRING(F32SYS);
CHECK_FMT_STRING(F32);
362
#undef CHECK_FMT_STRING
363
return 0;
364
365
}
366
367
int
SDL_GetNumAudioDrivers(void)
368
{
369
370
return (SDL_arraysize(bootstrap) - 1);
}
371
372
373
374
375
376
377
378
379
380
381
382
383
const char *
SDL_GetAudioDriver(int index)
{
if (index >= 0 && index < SDL_GetNumAudioDrivers()) {
return (bootstrap[index]->name);
}
return (NULL);
}
int
SDL_AudioInit(const char *driver_name)
{
384
385
386
int i = 0;
int initialized = 0;
int tried_to_init = 0;
387
388
if (SDL_WasInit(SDL_INIT_AUDIO)) {
389
SDL_AudioQuit(); /* shutdown driver if already running. */
390
391
}
392
393
SDL_memset(¤t_audio, '\0', sizeof(current_audio));
SDL_memset(open_devices, '\0', sizeof(open_devices));
394
395
/* Select the proper audio driver */
396
397
398
if (driver_name == NULL) {
driver_name = SDL_getenv("SDL_AUDIODRIVER");
}
399
400
401
402
for (i = 0; (!initialized) && (bootstrap[i]); ++i) {
/* make sure we should even try this driver before doing so... */
const AudioBootStrap *backend = bootstrap[i];
403
404
if (((driver_name) && (SDL_strcasecmp(backend->name, driver_name))) ||
((!driver_name) && (backend->demand_only))) {
405
continue;
406
}
407
408
tried_to_init = 1;
409
SDL_memset(¤t_audio, 0, sizeof(current_audio));
410
411
412
current_audio.name = backend->name;
current_audio.desc = backend->desc;
initialized = backend->init(¤t_audio.impl);
413
}
414
415
416
417
if (!initialized) {
/* specific drivers will set the error message if they fail... */
if (!tried_to_init) {
418
419
420
421
422
423
if (driver_name) {
SDL_SetError("%s not available", driver_name);
} else {
SDL_SetError("No available audio device");
}
}
424
425
426
SDL_memset(¤t_audio, 0, sizeof(current_audio));
return (-1); /* No driver was available, so fail. */
427
}
428
429
430
finalize_audio_entry_points();
431
return (0);
432
433
}
434
435
436
437
438
/*
* Get the current audio driver name
*/
const char *
SDL_GetCurrentAudioDriver()
439
{
440
return current_audio.name;
441
442
}
443
444
int
445
SDL_GetNumAudioDevices(int iscapture)
446
{
447
448
449
450
451
452
if (!SDL_WasInit(SDL_INIT_AUDIO)) {
return -1;
}
if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) {
return 0;
}
453
454
455
if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) {
return 1;
456
457
}
458
459
if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) {
return 1;
460
461
}
462
463
464
465
466
467
468
469
470
471
return current_audio.impl.DetectDevices(iscapture);
}
const char *
SDL_GetAudioDeviceName(int index, int iscapture)
{
if (!SDL_WasInit(SDL_INIT_AUDIO)) {
SDL_SetError("Audio subsystem is not initialized");
return NULL;
472
}
473
474
475
476
if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) {
SDL_SetError("No capture support");
return NULL;
477
}
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
if (index < 0) {
SDL_SetError("No such device");
return NULL;
}
if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) {
return DEFAULT_INPUT_DEVNAME;
}
if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) {
return DEFAULT_OUTPUT_DEVNAME;
}
return current_audio.impl.GetDeviceName(index, iscapture);
}
static void
497
close_audio_device(SDL_AudioDevice * device)
498
499
500
501
502
503
504
{
device->enabled = 0;
if (device->thread != NULL) {
SDL_WaitThread(device->thread, NULL);
}
if (device->mixer_lock != NULL) {
SDL_DestroyMutex(device->mixer_lock);
505
}
506
507
if (device->fake_stream != NULL) {
SDL_FreeAudioMem(device->fake_stream);
508
}
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
if (device->convert.needed) {
SDL_FreeAudioMem(device->convert.buf);
}
if (device->opened) {
current_audio.impl.CloseDevice(device);
device->opened = 0;
}
SDL_FreeAudioMem(device);
}
/*
* Sanity check desired AudioSpec for SDL_OpenAudio() in (orig).
* Fills in a sanitized copy in (prepared).
* Returns non-zero if okay, zero on fatal parameters in (orig).
*/
static int
526
prepare_audiospec(const SDL_AudioSpec * orig, SDL_AudioSpec * prepared)
527
{
528
SDL_memcpy(prepared, orig, sizeof(SDL_AudioSpec));
529
530
531
532
533
534
535
536
if (orig->callback == NULL) {
SDL_SetError("SDL_OpenAudio() passed a NULL callback");
return 0;
}
if (orig->freq == 0) {
const char *env = SDL_getenv("SDL_AUDIO_FREQUENCY");
537
538
if ((!env) || ((prepared->freq = SDL_atoi(env)) == 0)) {
prepared->freq = 22050; /* a reasonable default */
539
540
}
}
541
542
543
544
if (orig->format == 0) {
const char *env = SDL_getenv("SDL_AUDIO_FORMAT");
if ((!env) || ((prepared->format = SDL_ParseAudioFormat(env)) == 0)) {
545
prepared->format = AUDIO_S16; /* a reasonable default */
546
547
548
549
}
}
switch (orig->channels) {
550
551
case 0:{
const char *env = SDL_getenv("SDL_AUDIO_CHANNELS");
552
if ((!env) || ((prepared->channels = (Uint8) SDL_atoi(env)) == 0)) {
553
554
555
prepared->channels = 2; /* a reasonable default */
}
break;
556
}
557
558
559
560
561
562
case 1: /* Mono */
case 2: /* Stereo */
case 4: /* surround */
case 6: /* surround with center and lfe */
break;
default:
563
564
SDL_SetError("Unsupported number of audio channels.");
return 0;
565
}
566
567
568
if (orig->samples == 0) {
const char *env = SDL_getenv("SDL_AUDIO_SAMPLES");
569
if ((!env) || ((prepared->samples = (Uint16) SDL_atoi(env)) == 0)) {
570
571
572
573
574
575
576
577
/* Pick a default of ~46 ms at desired frequency */
/* !!! FIXME: remove this when the non-Po2 resampling is in. */
const int samples = (prepared->freq / 1000) * 46;
int power2 = 1;
while (power2 < samples) {
power2 *= 2;
}
prepared->samples = power2;
578
579
}
}
580
581
582
583
584
585
586
587
588
589
/* Calculate the silence and size of the audio specification */
SDL_CalculateAudioSpec(prepared);
return 1;
}
static SDL_AudioDeviceID
open_audio_device(const char *devname, int iscapture,
590
591
const SDL_AudioSpec * _desired, SDL_AudioSpec * obtained,
int min_id)
592
593
594
595
596
597
598
599
600
{
SDL_AudioDeviceID id = 0;
SDL_AudioSpec desired;
SDL_AudioDevice *device;
int i = 0;
if (!SDL_WasInit(SDL_INIT_AUDIO)) {
SDL_SetError("Audio subsystem is not initialized");
return 0;
601
}
602
603
604
605
if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) {
SDL_SetError("No capture support");
return 0;
606
}
607
608
609
610
if (!prepare_audiospec(_desired, &desired)) {
return 0;
}
611
612
613
614
615
/* If app doesn't care about a specific device, let the user override. */
if (devname == NULL) {
devname = SDL_getenv("SDL_AUDIO_DEVICE_NAME");
}
616
617
618
619
620
621
622
623
624
625
/*
* Catch device names at the high level for the simple case...
* This lets us have a basic "device enumeration" for systems that
* don't have multiple devices, but makes sure the device name is
* always NULL when it hits the low level.
*
* Also make sure that the simple case prevents multiple simultaneous
* opens of the default system device.
*/
626
627
628
629
630
631
632
if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) {
if ((devname) && (SDL_strcmp(devname, DEFAULT_INPUT_DEVNAME) != 0)) {
SDL_SetError("No such device");
return 0;
}
devname = NULL;
633
634
635
636
637
638
639
for (i = 0; i < SDL_arraysize(open_devices); i++) {
if ((open_devices[i]) && (open_devices[i]->iscapture)) {
SDL_SetError("Audio device already open");
return 0;
}
}
640
641
}
642
643
644
645
646
647
if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) {
if ((devname) && (SDL_strcmp(devname, DEFAULT_OUTPUT_DEVNAME) != 0)) {
SDL_SetError("No such device");
return 0;
}
devname = NULL;
648
649
650
651
652
653
654
655
for (i = 0; i < SDL_arraysize(open_devices); i++) {
if ((open_devices[i]) && (!open_devices[i]->iscapture)) {
SDL_SetError("Audio device already open");
return 0;
}
}
}
656
657
device = (SDL_AudioDevice *) SDL_AllocAudioMem(sizeof(SDL_AudioDevice));
658
659
660
if (device == NULL) {
SDL_OutOfMemory();
return 0;
661
}
662
663
SDL_memset(device, '\0', sizeof(SDL_AudioDevice));
SDL_memcpy(&device->spec, &desired, sizeof(SDL_AudioSpec));
664
665
666
device->enabled = 1;
device->paused = 1;
device->iscapture = iscapture;
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
/* Create a semaphore for locking the sound buffers */
if (!current_audio.impl.SkipMixerLock) {
device->mixer_lock = SDL_CreateMutex();
if (device->mixer_lock == NULL) {
close_audio_device(device);
SDL_SetError("Couldn't create mixer lock");
return 0;
}
}
if (!current_audio.impl.OpenDevice(device, devname, iscapture)) {
close_audio_device(device);
return 0;
}
device->opened = 1;
683
684
/* If the audio driver changes the buffer size, accept it */
685
686
687
if (device->spec.samples != desired.samples) {
desired.samples = device->spec.samples;
SDL_CalculateAudioSpec(&device->spec);
688
689
690
}
/* Allocate a fake audio memory buffer */
691
692
693
device->fake_stream = SDL_AllocAudioMem(device->spec.size);
if (device->fake_stream == NULL) {
close_audio_device(device);
694
SDL_OutOfMemory();
695
return 0;
696
697
698
699
}
/* See if we need to do any conversion */
if (obtained != NULL) {
700
701
702
703
SDL_memcpy(obtained, &device->spec, sizeof(SDL_AudioSpec));
} else if (desired.freq != device->spec.freq ||
desired.format != device->spec.format ||
desired.channels != device->spec.channels) {
704
/* Build an audio conversion block */
705
706
707
708
709
710
711
if (SDL_BuildAudioCVT(&device->convert,
desired.format, desired.channels,
desired.freq,
device->spec.format, device->spec.channels,
device->spec.freq) < 0) {
close_audio_device(device);
return 0;
712
}
713
if (device->convert.needed) {
714
715
device->convert.len = (int) (((double) desired.size) /
device->convert.len_ratio);
716
717
718
719
720
721
device->convert.buf =
(Uint8 *) SDL_AllocAudioMem(device->convert.len *
device->convert.len_mult);
if (device->convert.buf == NULL) {
close_audio_device(device);
722
SDL_OutOfMemory();
723
return 0;
724
725
726
}
}
}
727
728
/* Find an available device ID and store the structure... */
729
for (id = min_id - 1; id < SDL_arraysize(open_devices); id++) {
730
731
732
733
734
735
736
737
738
739
740
741
if (open_devices[id] == NULL) {
open_devices[id] = device;
break;
}
}
if (id == SDL_arraysize(open_devices)) {
SDL_SetError("Too many open audio devices");
close_audio_device(device);
return 0;
}
742
/* Start the audio thread if necessary */
743
if (!current_audio.impl.ProvidesOwnCallbackThread) {
744
/* Start the audio thread */
745
/* !!! FIXME: this is nasty. */
746
#if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC)
747
#undef SDL_CreateThread
748
device->thread = SDL_CreateThread(SDL_RunAudio, device, NULL, NULL);
749
#else
750
device->thread = SDL_CreateThread(SDL_RunAudio, device);
751
#endif
752
if (device->thread == NULL) {
753
SDL_CloseAudioDevice(id + 1);
754
SDL_SetError("Couldn't create audio thread");
755
756
757
758
return 0;
}
}
759
return id + 1;
760
761
762
763
764
765
766
767
768
769
770
}
int
SDL_OpenAudio(const SDL_AudioSpec * desired, SDL_AudioSpec * obtained)
{
SDL_AudioDeviceID id = 0;
/* Start up the audio driver, if necessary. This is legacy behaviour! */
if (!SDL_WasInit(SDL_INIT_AUDIO)) {
if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) {
771
772
return (-1);
}
773
}
774
775
776
777
778
/* SDL_OpenAudio() is legacy and can only act on Device ID #1. */
if (open_devices[0] != NULL) {
SDL_SetError("Audio device is already opened");
return (-1);
779
}
780
781
id = open_audio_device(NULL, 0, desired, obtained, 1);
782
if (id > 1) { /* this should never happen in theory... */
783
SDL_CloseAudioDevice(id);
784
SDL_SetError("Internal error"); /* MUST be Device ID #1! */
785
786
return (-1);
}
787
788
return ((id == 0) ? -1 : 0);
789
790
}
791
792
SDL_AudioDeviceID
SDL_OpenAudioDevice(const char *device, int iscapture,
793
const SDL_AudioSpec * desired, SDL_AudioSpec * obtained)
794
{
795
796
return open_audio_device(device, iscapture, desired, obtained, 2);
}
797
798
799
800
801
802
803
804
SDL_audiostatus
SDL_GetAudioDeviceStatus(SDL_AudioDeviceID devid)
{
SDL_AudioDevice *device = get_audio_device(devid);
SDL_audiostatus status = SDL_AUDIO_STOPPED;
if (device && device->enabled) {
if (device->paused) {
805
806
807
808
809
810
status = SDL_AUDIO_PAUSED;
} else {
status = SDL_AUDIO_PLAYING;
}
}
return (status);
811
812
}
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
SDL_audiostatus
SDL_GetAudioStatus(void)
{
return SDL_GetAudioDeviceStatus(1);
}
void
SDL_PauseAudioDevice(SDL_AudioDeviceID devid, int pause_on)
{
SDL_AudioDevice *device = get_audio_device(devid);
if (device) {
device->paused = pause_on;
}
}
829
830
void
SDL_PauseAudio(int pause_on)
831
{
832
833
834
SDL_PauseAudioDevice(1, pause_on);
}
835
836
837
838
839
840
841
842
void
SDL_LockAudioDevice(SDL_AudioDeviceID devid)
{
/* Obtain a lock on the mixing buffers */
SDL_AudioDevice *device = get_audio_device(devid);
if (device) {
current_audio.impl.LockDevice(device);
843
}
844
845
}
846
847
void
SDL_LockAudio(void)
848
{
849
850
SDL_LockAudioDevice(1);
}
851
852
853
854
void
SDL_UnlockAudioDevice(SDL_AudioDeviceID devid)
{
855
/* Obtain a lock on the mixing buffers */
856
857
858
SDL_AudioDevice *device = get_audio_device(devid);
if (device) {
current_audio.impl.UnlockDevice(device);
859
}
860
861
}
862
863
void
SDL_UnlockAudio(void)
864
{
865
866
SDL_UnlockAudioDevice(1);
}
867
868
869
870
871
872
873
void
SDL_CloseAudioDevice(SDL_AudioDeviceID devid)
{
SDL_AudioDevice *device = get_audio_device(devid);
if (device) {
close_audio_device(device);
874
open_devices[devid - 1] = NULL;
875
}
876
877
}
878
879
void
SDL_CloseAudio(void)
880
{
881
SDL_CloseAudioDevice(1);
882
883
}
884
885
void
SDL_AudioQuit(void)
886
{
887
888
889
SDL_AudioDeviceID i;
for (i = 0; i < SDL_arraysize(open_devices); i++) {
SDL_CloseAudioDevice(i);
890
}
891
892
893
/* Free the driver data */
current_audio.impl.Deinitialize();
894
895
SDL_memset(¤t_audio, '\0', sizeof(current_audio));
SDL_memset(open_devices, '\0', sizeof(open_devices));
896
897
}
898
#define NUM_FORMATS 10
899
900
static int format_idx;
static int format_idx_sub;
901
static SDL_AudioFormat format_list[NUM_FORMATS][NUM_FORMATS] = {
902
{AUDIO_U8, AUDIO_S8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB,
903
AUDIO_U16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB},
904
{AUDIO_S8, AUDIO_U8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB,
905
906
907
908
909
910
911
912
913
AUDIO_U16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB},
{AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S32LSB,
AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_U8, AUDIO_S8},
{AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S32MSB,
AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_U8, AUDIO_S8},
{AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_S32LSB,
AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_U8, AUDIO_S8},
{AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_S32MSB,
AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_U8, AUDIO_S8},
914
915
916
917
918
919
920
921
{AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_S16LSB,
AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8, AUDIO_S8},
{AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_S16MSB,
AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8, AUDIO_S8},
{AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_S16LSB,
AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8, AUDIO_S8},
{AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_S16MSB,
AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8, AUDIO_S8},
922
923
};
924
925
SDL_AudioFormat
SDL_FirstAudioFormat(SDL_AudioFormat format)
926
{
927
928
929
930
931
932
933
for (format_idx = 0; format_idx < NUM_FORMATS; ++format_idx) {
if (format_list[format_idx][0] == format) {
break;
}
}
format_idx_sub = 0;
return (SDL_NextAudioFormat());
934
935
}
936
SDL_AudioFormat
937
SDL_NextAudioFormat(void)
938
{
939
940
941
942
if ((format_idx == NUM_FORMATS) || (format_idx_sub == NUM_FORMATS)) {
return (0);
}
return (format_list[format_idx][format_idx_sub++]);
943
944
}
945
946
void
SDL_CalculateAudioSpec(SDL_AudioSpec * spec)
947
{
948
949
950
951
952
953
954
955
switch (spec->format) {
case AUDIO_U8:
spec->silence = 0x80;
break;
default:
spec->silence = 0x00;
break;
}
956
spec->size = SDL_AUDIO_BITSIZE(spec->format) / 8;
957
958
spec->size *= spec->channels;
spec->size *= spec->samples;
959
}
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
/*
* Moved here from SDL_mixer.c, since it relies on internals of an opened
* audio device (and is deprecated, by the way!).
*/
void
SDL_MixAudio(Uint8 * dst, const Uint8 * src, Uint32 len, int volume)
{
/* Mix the user-level audio format */
SDL_AudioDevice *device = get_audio_device(1);
if (device != NULL) {
SDL_AudioFormat format;
if (device->convert.needed) {
format = device->convert.src_format;
} else {
format = device->spec.format;
}
SDL_MixAudioFormat(dst, src, format, len, volume);
}
}
982
/* vi: set ts=4 sw=4 expandtab: */