1 /*
2  * QEMU DirectSound audio driver
3  *
4  * Copyright (c) 2005 Vassili Karpov (malc)
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 /*
26  * SEAL 1.07 by Carlos 'pel' Hasan was used as documentation
27  */
28 
29 #include "qemu/osdep.h"
30 #include "audio.h"
31 
32 #define AUDIO_CAP "dsound"
33 #include "audio_int.h"
34 #include "qemu/host-utils.h"
35 #include "qemu/module.h"
36 
37 #include <windows.h>
38 #include <mmsystem.h>
39 #include <objbase.h>
40 #include <dsound.h>
41 
42 #include "audio_win_int.h"
43 
44 /* #define DEBUG_DSOUND */
45 
46 typedef struct {
47     LPDIRECTSOUND dsound;
48     LPDIRECTSOUNDCAPTURE dsound_capture;
49     struct audsettings settings;
50     Audiodev *dev;
51 } dsound;
52 
53 typedef struct {
54     HWVoiceOut hw;
55     LPDIRECTSOUNDBUFFER dsound_buffer;
56     dsound *s;
57 } DSoundVoiceOut;
58 
59 typedef struct {
60     HWVoiceIn hw;
61     LPDIRECTSOUNDCAPTUREBUFFER dsound_capture_buffer;
62     dsound *s;
63 } DSoundVoiceIn;
64 
dsound_log_hresult(HRESULT hr)65 static void dsound_log_hresult (HRESULT hr)
66 {
67     const char *str = "BUG";
68 
69     switch (hr) {
70     case DS_OK:
71         str = "The method succeeded";
72         break;
73 #ifdef DS_NO_VIRTUALIZATION
74     case DS_NO_VIRTUALIZATION:
75         str = "The buffer was created, but another 3D algorithm was substituted";
76         break;
77 #endif
78 #ifdef DS_INCOMPLETE
79     case DS_INCOMPLETE:
80         str = "The method succeeded, but not all the optional effects were obtained";
81         break;
82 #endif
83 #ifdef DSERR_ACCESSDENIED
84     case DSERR_ACCESSDENIED:
85         str = "The request failed because access was denied";
86         break;
87 #endif
88 #ifdef DSERR_ALLOCATED
89     case DSERR_ALLOCATED:
90         str = "The request failed because resources, such as a priority level, were already in use by another caller";
91         break;
92 #endif
93 #ifdef DSERR_ALREADYINITIALIZED
94     case DSERR_ALREADYINITIALIZED:
95         str = "The object is already initialized";
96         break;
97 #endif
98 #ifdef DSERR_BADFORMAT
99     case DSERR_BADFORMAT:
100         str = "The specified wave format is not supported";
101         break;
102 #endif
103 #ifdef DSERR_BADSENDBUFFERGUID
104     case DSERR_BADSENDBUFFERGUID:
105         str = "The GUID specified in an audiopath file does not match a valid mix-in buffer";
106         break;
107 #endif
108 #ifdef DSERR_BUFFERLOST
109     case DSERR_BUFFERLOST:
110         str = "The buffer memory has been lost and must be restored";
111         break;
112 #endif
113 #ifdef DSERR_BUFFERTOOSMALL
114     case DSERR_BUFFERTOOSMALL:
115         str = "The buffer size is not great enough to enable effects processing";
116         break;
117 #endif
118 #ifdef DSERR_CONTROLUNAVAIL
119     case DSERR_CONTROLUNAVAIL:
120         str = "The buffer control (volume, pan, and so on) requested by the caller is not available. Controls must be specified when the buffer is created, using the dwFlags member of DSBUFFERDESC";
121         break;
122 #endif
123 #ifdef DSERR_DS8_REQUIRED
124     case DSERR_DS8_REQUIRED:
125         str = "A DirectSound object of class CLSID_DirectSound8 or later is required for the requested functionality. For more information, see IDirectSound8 Interface";
126         break;
127 #endif
128 #ifdef DSERR_FXUNAVAILABLE
129     case DSERR_FXUNAVAILABLE:
130         str = "The effects requested could not be found on the system, or they are in the wrong order or in the wrong location; for example, an effect expected in hardware was found in software";
131         break;
132 #endif
133 #ifdef DSERR_GENERIC
134     case DSERR_GENERIC :
135         str = "An undetermined error occurred inside the DirectSound subsystem";
136         break;
137 #endif
138 #ifdef DSERR_INVALIDCALL
139     case DSERR_INVALIDCALL:
140         str = "This function is not valid for the current state of this object";
141         break;
142 #endif
143 #ifdef DSERR_INVALIDPARAM
144     case DSERR_INVALIDPARAM:
145         str = "An invalid parameter was passed to the returning function";
146         break;
147 #endif
148 #ifdef DSERR_NOAGGREGATION
149     case DSERR_NOAGGREGATION:
150         str = "The object does not support aggregation";
151         break;
152 #endif
153 #ifdef DSERR_NODRIVER
154     case DSERR_NODRIVER:
155         str = "No sound driver is available for use, or the given GUID is not a valid DirectSound device ID";
156         break;
157 #endif
158 #ifdef DSERR_NOINTERFACE
159     case DSERR_NOINTERFACE:
160         str = "The requested COM interface is not available";
161         break;
162 #endif
163 #ifdef DSERR_OBJECTNOTFOUND
164     case DSERR_OBJECTNOTFOUND:
165         str = "The requested object was not found";
166         break;
167 #endif
168 #ifdef DSERR_OTHERAPPHASPRIO
169     case DSERR_OTHERAPPHASPRIO:
170         str = "Another application has a higher priority level, preventing this call from succeeding";
171         break;
172 #endif
173 #ifdef DSERR_OUTOFMEMORY
174     case DSERR_OUTOFMEMORY:
175         str = "The DirectSound subsystem could not allocate sufficient memory to complete the caller's request";
176         break;
177 #endif
178 #ifdef DSERR_PRIOLEVELNEEDED
179     case DSERR_PRIOLEVELNEEDED:
180         str = "A cooperative level of DSSCL_PRIORITY or higher is required";
181         break;
182 #endif
183 #ifdef DSERR_SENDLOOP
184     case DSERR_SENDLOOP:
185         str = "A circular loop of send effects was detected";
186         break;
187 #endif
188 #ifdef DSERR_UNINITIALIZED
189     case DSERR_UNINITIALIZED:
190         str = "The Initialize method has not been called or has not been called successfully before other methods were called";
191         break;
192 #endif
193 #ifdef DSERR_UNSUPPORTED
194     case DSERR_UNSUPPORTED:
195         str = "The function called is not supported at this time";
196         break;
197 #endif
198     default:
199         AUD_log (AUDIO_CAP, "Reason: Unknown (HRESULT %#lx)\n", hr);
200         return;
201     }
202 
203     AUD_log (AUDIO_CAP, "Reason: %s\n", str);
204 }
205 
dsound_logerr(HRESULT hr,const char * fmt,...)206 static void GCC_FMT_ATTR (2, 3) dsound_logerr (
207     HRESULT hr,
208     const char *fmt,
209     ...
210     )
211 {
212     va_list ap;
213 
214     va_start (ap, fmt);
215     AUD_vlog (AUDIO_CAP, fmt, ap);
216     va_end (ap);
217 
218     dsound_log_hresult (hr);
219 }
220 
dsound_logerr2(HRESULT hr,const char * typ,const char * fmt,...)221 static void GCC_FMT_ATTR (3, 4) dsound_logerr2 (
222     HRESULT hr,
223     const char *typ,
224     const char *fmt,
225     ...
226     )
227 {
228     va_list ap;
229 
230     AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
231     va_start (ap, fmt);
232     AUD_vlog (AUDIO_CAP, fmt, ap);
233     va_end (ap);
234 
235     dsound_log_hresult (hr);
236 }
237 
238 #ifdef DEBUG_DSOUND
print_wave_format(WAVEFORMATEX * wfx)239 static void print_wave_format (WAVEFORMATEX *wfx)
240 {
241     dolog ("tag             = %d\n", wfx->wFormatTag);
242     dolog ("nChannels       = %d\n", wfx->nChannels);
243     dolog ("nSamplesPerSec  = %ld\n", wfx->nSamplesPerSec);
244     dolog ("nAvgBytesPerSec = %ld\n", wfx->nAvgBytesPerSec);
245     dolog ("nBlockAlign     = %d\n", wfx->nBlockAlign);
246     dolog ("wBitsPerSample  = %d\n", wfx->wBitsPerSample);
247     dolog ("cbSize          = %d\n", wfx->cbSize);
248 }
249 #endif
250 
dsound_restore_out(LPDIRECTSOUNDBUFFER dsb,dsound * s)251 static int dsound_restore_out (LPDIRECTSOUNDBUFFER dsb, dsound *s)
252 {
253     HRESULT hr;
254 
255     hr = IDirectSoundBuffer_Restore (dsb);
256 
257     if (hr != DS_OK) {
258         dsound_logerr (hr, "Could not restore playback buffer\n");
259         return -1;
260     }
261     return 0;
262 }
263 
264 #include "dsound_template.h"
265 #define DSBTYPE_IN
266 #include "dsound_template.h"
267 #undef DSBTYPE_IN
268 
dsound_get_status_out(LPDIRECTSOUNDBUFFER dsb,DWORD * statusp,dsound * s)269 static int dsound_get_status_out (LPDIRECTSOUNDBUFFER dsb, DWORD *statusp,
270                                   dsound *s)
271 {
272     HRESULT hr;
273 
274     hr = IDirectSoundBuffer_GetStatus (dsb, statusp);
275     if (FAILED (hr)) {
276         dsound_logerr (hr, "Could not get playback buffer status\n");
277         return -1;
278     }
279 
280     if (*statusp & DSERR_BUFFERLOST) {
281         dsound_restore_out(dsb, s);
282         return -1;
283     }
284 
285     return 0;
286 }
287 
dsound_get_status_in(LPDIRECTSOUNDCAPTUREBUFFER dscb,DWORD * statusp)288 static int dsound_get_status_in (LPDIRECTSOUNDCAPTUREBUFFER dscb,
289                                  DWORD *statusp)
290 {
291     HRESULT hr;
292 
293     hr = IDirectSoundCaptureBuffer_GetStatus (dscb, statusp);
294     if (FAILED (hr)) {
295         dsound_logerr (hr, "Could not get capture buffer status\n");
296         return -1;
297     }
298 
299     return 0;
300 }
301 
dsound_clear_sample(HWVoiceOut * hw,LPDIRECTSOUNDBUFFER dsb,dsound * s)302 static void dsound_clear_sample (HWVoiceOut *hw, LPDIRECTSOUNDBUFFER dsb,
303                                  dsound *s)
304 {
305     int err;
306     LPVOID p1, p2;
307     DWORD blen1, blen2, len1, len2;
308 
309     err = dsound_lock_out (
310         dsb,
311         &hw->info,
312         0,
313         hw->size_emul,
314         &p1, &p2,
315         &blen1, &blen2,
316         1,
317         s
318         );
319     if (err) {
320         return;
321     }
322 
323     len1 = blen1 / hw->info.bytes_per_frame;
324     len2 = blen2 / hw->info.bytes_per_frame;
325 
326 #ifdef DEBUG_DSOUND
327     dolog ("clear %p,%ld,%ld %p,%ld,%ld\n",
328            p1, blen1, len1,
329            p2, blen2, len2);
330 #endif
331 
332     if (p1 && len1) {
333         audio_pcm_info_clear_buf (&hw->info, p1, len1);
334     }
335 
336     if (p2 && len2) {
337         audio_pcm_info_clear_buf (&hw->info, p2, len2);
338     }
339 
340     dsound_unlock_out (dsb, p1, p2, blen1, blen2);
341 }
342 
dsound_open(dsound * s)343 static int dsound_open (dsound *s)
344 {
345     HRESULT hr;
346     HWND hwnd;
347 
348     hwnd = GetForegroundWindow ();
349     hr = IDirectSound_SetCooperativeLevel (
350         s->dsound,
351         hwnd,
352         DSSCL_PRIORITY
353         );
354 
355     if (FAILED (hr)) {
356         dsound_logerr (hr, "Could not set cooperative level for window %p\n",
357                        hwnd);
358         return -1;
359     }
360 
361     return 0;
362 }
363 
dsound_enable_out(HWVoiceOut * hw,bool enable)364 static void dsound_enable_out(HWVoiceOut *hw, bool enable)
365 {
366     HRESULT hr;
367     DWORD status;
368     DSoundVoiceOut *ds = (DSoundVoiceOut *) hw;
369     LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
370     dsound *s = ds->s;
371 
372     if (!dsb) {
373         dolog ("Attempt to control voice without a buffer\n");
374         return;
375     }
376 
377     if (enable) {
378         if (dsound_get_status_out (dsb, &status, s)) {
379             return;
380         }
381 
382         if (status & DSBSTATUS_PLAYING) {
383             dolog ("warning: Voice is already playing\n");
384             return;
385         }
386 
387         dsound_clear_sample (hw, dsb, s);
388 
389         hr = IDirectSoundBuffer_Play (dsb, 0, 0, DSBPLAY_LOOPING);
390         if (FAILED (hr)) {
391             dsound_logerr (hr, "Could not start playing buffer\n");
392             return;
393         }
394     } else {
395         if (dsound_get_status_out (dsb, &status, s)) {
396             return;
397         }
398 
399         if (status & DSBSTATUS_PLAYING) {
400             hr = IDirectSoundBuffer_Stop (dsb);
401             if (FAILED (hr)) {
402                 dsound_logerr (hr, "Could not stop playing buffer\n");
403                 return;
404             }
405         }
406         else {
407             dolog ("warning: Voice is not playing\n");
408         }
409     }
410 }
411 
dsound_get_buffer_out(HWVoiceOut * hw,size_t * size)412 static void *dsound_get_buffer_out(HWVoiceOut *hw, size_t *size)
413 {
414     DSoundVoiceOut *ds = (DSoundVoiceOut *) hw;
415     LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
416     HRESULT hr;
417     DWORD ppos, act_size;
418     size_t req_size;
419     int err;
420     void *ret;
421 
422     hr = IDirectSoundBuffer_GetCurrentPosition(dsb, &ppos, NULL);
423     if (FAILED(hr)) {
424         dsound_logerr(hr, "Could not get playback buffer position\n");
425         *size = 0;
426         return NULL;
427     }
428 
429     req_size = audio_ring_dist(ppos, hw->pos_emul, hw->size_emul);
430     req_size = MIN(req_size, hw->size_emul - hw->pos_emul);
431 
432     err = dsound_lock_out(dsb, &hw->info, hw->pos_emul, req_size, &ret, NULL,
433                           &act_size, NULL, false, ds->s);
434     if (err) {
435         dolog("Failed to lock buffer\n");
436         *size = 0;
437         return NULL;
438     }
439 
440     *size = act_size;
441     return ret;
442 }
443 
dsound_put_buffer_out(HWVoiceOut * hw,void * buf,size_t len)444 static size_t dsound_put_buffer_out(HWVoiceOut *hw, void *buf, size_t len)
445 {
446     DSoundVoiceOut *ds = (DSoundVoiceOut *) hw;
447     LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
448     int err = dsound_unlock_out(dsb, buf, NULL, len, 0);
449 
450     if (err) {
451         dolog("Failed to unlock buffer!!\n");
452         return 0;
453     }
454     hw->pos_emul = (hw->pos_emul + len) % hw->size_emul;
455 
456     return len;
457 }
458 
dsound_enable_in(HWVoiceIn * hw,bool enable)459 static void dsound_enable_in(HWVoiceIn *hw, bool enable)
460 {
461     HRESULT hr;
462     DWORD status;
463     DSoundVoiceIn *ds = (DSoundVoiceIn *) hw;
464     LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;
465 
466     if (!dscb) {
467         dolog ("Attempt to control capture voice without a buffer\n");
468         return;
469     }
470 
471     if (enable) {
472         if (dsound_get_status_in (dscb, &status)) {
473             return;
474         }
475 
476         if (status & DSCBSTATUS_CAPTURING) {
477             dolog ("warning: Voice is already capturing\n");
478             return;
479         }
480 
481         /* clear ?? */
482 
483         hr = IDirectSoundCaptureBuffer_Start (dscb, DSCBSTART_LOOPING);
484         if (FAILED (hr)) {
485             dsound_logerr (hr, "Could not start capturing\n");
486             return;
487         }
488     } else {
489         if (dsound_get_status_in (dscb, &status)) {
490             return;
491         }
492 
493         if (status & DSCBSTATUS_CAPTURING) {
494             hr = IDirectSoundCaptureBuffer_Stop (dscb);
495             if (FAILED (hr)) {
496                 dsound_logerr (hr, "Could not stop capturing\n");
497                 return;
498             }
499         }
500         else {
501             dolog ("warning: Voice is not capturing\n");
502         }
503     }
504 }
505 
dsound_get_buffer_in(HWVoiceIn * hw,size_t * size)506 static void *dsound_get_buffer_in(HWVoiceIn *hw, size_t *size)
507 {
508     DSoundVoiceIn *ds = (DSoundVoiceIn *) hw;
509     LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;
510     HRESULT hr;
511     DWORD cpos, act_size;
512     size_t req_size;
513     int err;
514     void *ret;
515 
516     hr = IDirectSoundCaptureBuffer_GetCurrentPosition(dscb, &cpos, NULL);
517     if (FAILED(hr)) {
518         dsound_logerr(hr, "Could not get capture buffer position\n");
519         *size = 0;
520         return NULL;
521     }
522 
523     req_size = audio_ring_dist(cpos, hw->pos_emul, hw->size_emul);
524     req_size = MIN(req_size, hw->size_emul - hw->pos_emul);
525 
526     err = dsound_lock_in(dscb, &hw->info, hw->pos_emul, req_size, &ret, NULL,
527                          &act_size, NULL, false, ds->s);
528     if (err) {
529         dolog("Failed to lock buffer\n");
530         *size = 0;
531         return NULL;
532     }
533 
534     *size = act_size;
535     return ret;
536 }
537 
dsound_put_buffer_in(HWVoiceIn * hw,void * buf,size_t len)538 static void dsound_put_buffer_in(HWVoiceIn *hw, void *buf, size_t len)
539 {
540     DSoundVoiceIn *ds = (DSoundVoiceIn *) hw;
541     LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;
542     int err = dsound_unlock_in(dscb, buf, NULL, len, 0);
543 
544     if (err) {
545         dolog("Failed to unlock buffer!!\n");
546         return;
547     }
548     hw->pos_emul = (hw->pos_emul + len) % hw->size_emul;
549 }
550 
dsound_audio_fini(void * opaque)551 static void dsound_audio_fini (void *opaque)
552 {
553     HRESULT hr;
554     dsound *s = opaque;
555 
556     if (!s->dsound) {
557         g_free(s);
558         return;
559     }
560 
561     hr = IDirectSound_Release (s->dsound);
562     if (FAILED (hr)) {
563         dsound_logerr (hr, "Could not release DirectSound\n");
564     }
565     s->dsound = NULL;
566 
567     if (!s->dsound_capture) {
568         g_free(s);
569         return;
570     }
571 
572     hr = IDirectSoundCapture_Release (s->dsound_capture);
573     if (FAILED (hr)) {
574         dsound_logerr (hr, "Could not release DirectSoundCapture\n");
575     }
576     s->dsound_capture = NULL;
577 
578     g_free(s);
579 }
580 
dsound_audio_init(Audiodev * dev)581 static void *dsound_audio_init(Audiodev *dev)
582 {
583     int err;
584     HRESULT hr;
585     dsound *s = g_malloc0(sizeof(dsound));
586     AudiodevDsoundOptions *dso;
587 
588     assert(dev->driver == AUDIODEV_DRIVER_DSOUND);
589     s->dev = dev;
590     dso = &dev->u.dsound;
591 
592     if (!dso->has_latency) {
593         dso->has_latency = true;
594         dso->latency = 10000; /* 10 ms */
595     }
596 
597     hr = CoInitialize (NULL);
598     if (FAILED (hr)) {
599         dsound_logerr (hr, "Could not initialize COM\n");
600         g_free(s);
601         return NULL;
602     }
603 
604     hr = CoCreateInstance (
605         &CLSID_DirectSound,
606         NULL,
607         CLSCTX_ALL,
608         &IID_IDirectSound,
609         (void **) &s->dsound
610         );
611     if (FAILED (hr)) {
612         dsound_logerr (hr, "Could not create DirectSound instance\n");
613         g_free(s);
614         return NULL;
615     }
616 
617     hr = IDirectSound_Initialize (s->dsound, NULL);
618     if (FAILED (hr)) {
619         dsound_logerr (hr, "Could not initialize DirectSound\n");
620 
621         hr = IDirectSound_Release (s->dsound);
622         if (FAILED (hr)) {
623             dsound_logerr (hr, "Could not release DirectSound\n");
624         }
625         g_free(s);
626         return NULL;
627     }
628 
629     hr = CoCreateInstance (
630         &CLSID_DirectSoundCapture,
631         NULL,
632         CLSCTX_ALL,
633         &IID_IDirectSoundCapture,
634         (void **) &s->dsound_capture
635         );
636     if (FAILED (hr)) {
637         dsound_logerr (hr, "Could not create DirectSoundCapture instance\n");
638     }
639     else {
640         hr = IDirectSoundCapture_Initialize (s->dsound_capture, NULL);
641         if (FAILED (hr)) {
642             dsound_logerr (hr, "Could not initialize DirectSoundCapture\n");
643 
644             hr = IDirectSoundCapture_Release (s->dsound_capture);
645             if (FAILED (hr)) {
646                 dsound_logerr (hr, "Could not release DirectSoundCapture\n");
647             }
648             s->dsound_capture = NULL;
649         }
650     }
651 
652     err = dsound_open (s);
653     if (err) {
654         dsound_audio_fini (s);
655         return NULL;
656     }
657 
658     return s;
659 }
660 
661 static struct audio_pcm_ops dsound_pcm_ops = {
662     .init_out = dsound_init_out,
663     .fini_out = dsound_fini_out,
664     .write    = audio_generic_write,
665     .get_buffer_out = dsound_get_buffer_out,
666     .put_buffer_out = dsound_put_buffer_out,
667     .enable_out = dsound_enable_out,
668 
669     .init_in  = dsound_init_in,
670     .fini_in  = dsound_fini_in,
671     .read     = audio_generic_read,
672     .get_buffer_in = dsound_get_buffer_in,
673     .put_buffer_in = dsound_put_buffer_in,
674     .enable_in = dsound_enable_in,
675 };
676 
677 static struct audio_driver dsound_audio_driver = {
678     .name           = "dsound",
679     .descr          = "DirectSound http://wikipedia.org/wiki/DirectSound",
680     .init           = dsound_audio_init,
681     .fini           = dsound_audio_fini,
682     .pcm_ops        = &dsound_pcm_ops,
683     .can_be_default = 1,
684     .max_voices_out = INT_MAX,
685     .max_voices_in  = 1,
686     .voice_size_out = sizeof (DSoundVoiceOut),
687     .voice_size_in  = sizeof (DSoundVoiceIn)
688 };
689 
register_audio_dsound(void)690 static void register_audio_dsound(void)
691 {
692     audio_driver_register(&dsound_audio_driver);
693 }
694 type_init(register_audio_dsound);
695