audio/dsoundaudio.c - qemu - Git at Google

 /*
  * QEMU DirectSound audio driver
  *
  * Copyright (c) 2005 Vassili Karpov (malc)
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 /*
  * SEAL 1.07 by Carlos 'pel' Hasan was used as documentation
  */

 #include "qemu/osdep.h"
 #include "qemu-common.h"
 #include "audio.h"

 #define AUDIO_CAP "dsound"
 #include "audio_int.h"
 #include "qemu/host-utils.h"

 #include <windows.h>
 #include <mmsystem.h>
 #include <objbase.h>
 #include <dsound.h>

 #include "audio_win_int.h"

 /* #define DEBUG_DSOUND */

 typedef struct {
     LPDIRECTSOUND dsound;
     LPDIRECTSOUNDCAPTURE dsound_capture;
     struct audsettings settings;
     Audiodev *dev;
 } dsound;

 typedef struct {
     HWVoiceOut hw;
     LPDIRECTSOUNDBUFFER dsound_buffer;
     DWORD old_pos;
     int first_time;
     dsound *s;
 #ifdef DEBUG_DSOUND
     DWORD old_ppos;
     DWORD played;
     DWORD mixed;
 #endif
 } DSoundVoiceOut;

 typedef struct {
     HWVoiceIn hw;
     int first_time;
     LPDIRECTSOUNDCAPTUREBUFFER dsound_capture_buffer;
     dsound *s;
 } DSoundVoiceIn;

 static void dsound_log_hresult (HRESULT hr)
 {
     const char *str = "BUG";

     switch (hr) {
     case DS_OK:
         str = "The method succeeded";
         break;
 #ifdef DS_NO_VIRTUALIZATION
     case DS_NO_VIRTUALIZATION:
         str = "The buffer was created, but another 3D algorithm was substituted";
         break;
 #endif
 #ifdef DS_INCOMPLETE
     case DS_INCOMPLETE:
         str = "The method succeeded, but not all the optional effects were obtained";
         break;
 #endif
 #ifdef DSERR_ACCESSDENIED
     case DSERR_ACCESSDENIED:
         str = "The request failed because access was denied";
         break;
 #endif
 #ifdef DSERR_ALLOCATED
     case DSERR_ALLOCATED:
         str = "The request failed because resources, such as a priority level, were already in use by another caller";
         break;
 #endif
 #ifdef DSERR_ALREADYINITIALIZED
     case DSERR_ALREADYINITIALIZED:
         str = "The object is already initialized";
         break;
 #endif
 #ifdef DSERR_BADFORMAT
     case DSERR_BADFORMAT:
         str = "The specified wave format is not supported";
         break;
 #endif
 #ifdef DSERR_BADSENDBUFFERGUID
     case DSERR_BADSENDBUFFERGUID:
         str = "The GUID specified in an audiopath file does not match a valid mix-in buffer";
         break;
 #endif
 #ifdef DSERR_BUFFERLOST
     case DSERR_BUFFERLOST:
         str = "The buffer memory has been lost and must be restored";
         break;
 #endif
 #ifdef DSERR_BUFFERTOOSMALL
     case DSERR_BUFFERTOOSMALL:
         str = "The buffer size is not great enough to enable effects processing";
         break;
 #endif
 #ifdef DSERR_CONTROLUNAVAIL
     case DSERR_CONTROLUNAVAIL:
         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";
         break;
 #endif
 #ifdef DSERR_DS8_REQUIRED
     case DSERR_DS8_REQUIRED:
         str = "A DirectSound object of class CLSID_DirectSound8 or later is required for the requested functionality. For more information, see IDirectSound8 Interface";
         break;
 #endif
 #ifdef DSERR_FXUNAVAILABLE
     case DSERR_FXUNAVAILABLE:
         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";
         break;
 #endif
 #ifdef DSERR_GENERIC
     case DSERR_GENERIC :
         str = "An undetermined error occurred inside the DirectSound subsystem";
         break;
 #endif
 #ifdef DSERR_INVALIDCALL
     case DSERR_INVALIDCALL:
         str = "This function is not valid for the current state of this object";
         break;
 #endif
 #ifdef DSERR_INVALIDPARAM
     case DSERR_INVALIDPARAM:
         str = "An invalid parameter was passed to the returning function";
         break;
 #endif
 #ifdef DSERR_NOAGGREGATION
     case DSERR_NOAGGREGATION:
         str = "The object does not support aggregation";
         break;
 #endif
 #ifdef DSERR_NODRIVER
     case DSERR_NODRIVER:
         str = "No sound driver is available for use, or the given GUID is not a valid DirectSound device ID";
         break;
 #endif
 #ifdef DSERR_NOINTERFACE
     case DSERR_NOINTERFACE:
         str = "The requested COM interface is not available";
         break;
 #endif
 #ifdef DSERR_OBJECTNOTFOUND
     case DSERR_OBJECTNOTFOUND:
         str = "The requested object was not found";
         break;
 #endif
 #ifdef DSERR_OTHERAPPHASPRIO
     case DSERR_OTHERAPPHASPRIO:
         str = "Another application has a higher priority level, preventing this call from succeeding";
         break;
 #endif
 #ifdef DSERR_OUTOFMEMORY
     case DSERR_OUTOFMEMORY:
         str = "The DirectSound subsystem could not allocate sufficient memory to complete the caller's request";
         break;
 #endif
 #ifdef DSERR_PRIOLEVELNEEDED
     case DSERR_PRIOLEVELNEEDED:
         str = "A cooperative level of DSSCL_PRIORITY or higher is required";
         break;
 #endif
 #ifdef DSERR_SENDLOOP
     case DSERR_SENDLOOP:
         str = "A circular loop of send effects was detected";
         break;
 #endif
 #ifdef DSERR_UNINITIALIZED
     case DSERR_UNINITIALIZED:
         str = "The Initialize method has not been called or has not been called successfully before other methods were called";
         break;
 #endif
 #ifdef DSERR_UNSUPPORTED
     case DSERR_UNSUPPORTED:
         str = "The function called is not supported at this time";
         break;
 #endif
     default:
         AUD_log (AUDIO_CAP, "Reason: Unknown (HRESULT %#lx)\n", hr);
         return;
     }

     AUD_log (AUDIO_CAP, "Reason: %s\n", str);
 }

 static void GCC_FMT_ATTR (2, 3) dsound_logerr (
     HRESULT hr,
     const char *fmt,
     ...
     )
 {
     va_list ap;

     va_start (ap, fmt);
     AUD_vlog (AUDIO_CAP, fmt, ap);
     va_end (ap);

     dsound_log_hresult (hr);
 }

 static void GCC_FMT_ATTR (3, 4) dsound_logerr2 (
     HRESULT hr,
     const char *typ,
     const char *fmt,
     ...
     )
 {
     va_list ap;

     AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
     va_start (ap, fmt);
     AUD_vlog (AUDIO_CAP, fmt, ap);
     va_end (ap);

     dsound_log_hresult (hr);
 }

 static uint64_t usecs_to_bytes(struct audio_pcm_info *info, uint32_t usecs)
 {
     return muldiv64(usecs, info->bytes_per_second, 1000000);
 }

 #ifdef DEBUG_DSOUND
 static void print_wave_format (WAVEFORMATEX *wfx)
 {
     dolog ("tag             = %d\n", wfx->wFormatTag);
     dolog ("nChannels       = %d\n", wfx->nChannels);
     dolog ("nSamplesPerSec  = %ld\n", wfx->nSamplesPerSec);
     dolog ("nAvgBytesPerSec = %ld\n", wfx->nAvgBytesPerSec);
     dolog ("nBlockAlign     = %d\n", wfx->nBlockAlign);
     dolog ("wBitsPerSample  = %d\n", wfx->wBitsPerSample);
     dolog ("cbSize          = %d\n", wfx->cbSize);
 }
 #endif

 static int dsound_restore_out (LPDIRECTSOUNDBUFFER dsb, dsound *s)
 {
     HRESULT hr;

     hr = IDirectSoundBuffer_Restore (dsb);

     if (hr != DS_OK) {
         dsound_logerr (hr, "Could not restore playback buffer\n");
         return -1;
     }
     return 0;
 }

 #include "dsound_template.h"
 #define DSBTYPE_IN
 #include "dsound_template.h"
 #undef DSBTYPE_IN

 static int dsound_get_status_out (LPDIRECTSOUNDBUFFER dsb, DWORD *statusp,
                                   dsound *s)
 {
     HRESULT hr;

     hr = IDirectSoundBuffer_GetStatus (dsb, statusp);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not get playback buffer status\n");
         return -1;
     }

     if (*statusp & DSERR_BUFFERLOST) {
         dsound_restore_out(dsb, s);
         return -1;
     }

     return 0;
 }

 static int dsound_get_status_in (LPDIRECTSOUNDCAPTUREBUFFER dscb,
                                  DWORD *statusp)
 {
     HRESULT hr;

     hr = IDirectSoundCaptureBuffer_GetStatus (dscb, statusp);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not get capture buffer status\n");
         return -1;
     }

     return 0;
 }

 static void dsound_write_sample (HWVoiceOut *hw, uint8_t *dst, int dst_len)
 {
     int src_len1 = dst_len;
     int src_len2 = 0;
     int pos = hw->rpos + dst_len;
     struct st_sample *src1 = hw->mix_buf + hw->rpos;
     struct st_sample *src2 = NULL;

     if (pos > hw->samples) {
         src_len1 = hw->samples - hw->rpos;
         src2 = hw->mix_buf;
         src_len2 = dst_len - src_len1;
         pos = src_len2;
     }

     if (src_len1) {
         hw->clip (dst, src1, src_len1);
     }

     if (src_len2) {
         dst = advance (dst, src_len1 << hw->info.shift);
         hw->clip (dst, src2, src_len2);
     }

     hw->rpos = pos % hw->samples;
 }

 static void dsound_clear_sample (HWVoiceOut *hw, LPDIRECTSOUNDBUFFER dsb,
                                  dsound *s)
 {
     int err;
     LPVOID p1, p2;
     DWORD blen1, blen2, len1, len2;

     err = dsound_lock_out (
         dsb,
         &hw->info,
         0,
         hw->samples << hw->info.shift,
         &p1, &p2,
         &blen1, &blen2,
         1,
         s
         );
     if (err) {
         return;
     }

     len1 = blen1 >> hw->info.shift;
     len2 = blen2 >> hw->info.shift;

 #ifdef DEBUG_DSOUND
     dolog ("clear %p,%ld,%ld %p,%ld,%ld\n",
            p1, blen1, len1,
            p2, blen2, len2);
 #endif

     if (p1 && len1) {
         audio_pcm_info_clear_buf (&hw->info, p1, len1);
     }

     if (p2 && len2) {
         audio_pcm_info_clear_buf (&hw->info, p2, len2);
     }

     dsound_unlock_out (dsb, p1, p2, blen1, blen2);
 }

 static int dsound_open (dsound *s)
 {
     HRESULT hr;
     HWND hwnd;

     hwnd = GetForegroundWindow ();
     hr = IDirectSound_SetCooperativeLevel (
         s->dsound,
         hwnd,
         DSSCL_PRIORITY
         );

     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not set cooperative level for window %p\n",
                        hwnd);
         return -1;
     }

     return 0;
 }

 static int dsound_ctl_out (HWVoiceOut *hw, int cmd, ...)
 {
     HRESULT hr;
     DWORD status;
     DSoundVoiceOut *ds = (DSoundVoiceOut *) hw;
     LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
     dsound *s = ds->s;

     if (!dsb) {
         dolog ("Attempt to control voice without a buffer\n");
         return 0;
     }

     switch (cmd) {
     case VOICE_ENABLE:
         if (dsound_get_status_out (dsb, &status, s)) {
             return -1;
         }

         if (status & DSBSTATUS_PLAYING) {
             dolog ("warning: Voice is already playing\n");
             return 0;
         }

         dsound_clear_sample (hw, dsb, s);

         hr = IDirectSoundBuffer_Play (dsb, 0, 0, DSBPLAY_LOOPING);
         if (FAILED (hr)) {
             dsound_logerr (hr, "Could not start playing buffer\n");
             return -1;
         }
         break;

     case VOICE_DISABLE:
         if (dsound_get_status_out (dsb, &status, s)) {
             return -1;
         }

         if (status & DSBSTATUS_PLAYING) {
             hr = IDirectSoundBuffer_Stop (dsb);
             if (FAILED (hr)) {
                 dsound_logerr (hr, "Could not stop playing buffer\n");
                 return -1;
             }
         }
         else {
             dolog ("warning: Voice is not playing\n");
         }
         break;
     }
     return 0;
 }

 static int dsound_write (SWVoiceOut *sw, void *buf, int len)
 {
     return audio_pcm_sw_write (sw, buf, len);
 }

 static int dsound_run_out (HWVoiceOut *hw, int live)
 {
     int err;
     HRESULT hr;
     DSoundVoiceOut *ds = (DSoundVoiceOut *) hw;
     LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
     int len, hwshift;
     DWORD blen1, blen2;
     DWORD len1, len2;
     DWORD decr;
     DWORD wpos, ppos, old_pos;
     LPVOID p1, p2;
     int bufsize;
     dsound *s = ds->s;
     AudiodevDsoundOptions *dso = &s->dev->u.dsound;

     if (!dsb) {
         dolog ("Attempt to run empty with playback buffer\n");
         return 0;
     }

     hwshift = hw->info.shift;
     bufsize = hw->samples << hwshift;

     hr = IDirectSoundBuffer_GetCurrentPosition (
         dsb,
         &ppos,
         ds->first_time ? &wpos : NULL
         );
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not get playback buffer position\n");
         return 0;
     }

     len = live << hwshift;

     if (ds->first_time) {
         if (dso->latency) {
             DWORD cur_blat;

             cur_blat = audio_ring_dist (wpos, ppos, bufsize);
             ds->first_time = 0;
             old_pos = wpos;
             old_pos +=
                 usecs_to_bytes(&hw->info, dso->latency) - cur_blat;
             old_pos %= bufsize;
             old_pos &= ~hw->info.align;
         }
         else {
             old_pos = wpos;
         }
 #ifdef DEBUG_DSOUND
         ds->played = 0;
         ds->mixed = 0;
 #endif
     }
     else {
         if (ds->old_pos == ppos) {
 #ifdef DEBUG_DSOUND
             dolog ("old_pos == ppos\n");
 #endif
             return 0;
         }

 #ifdef DEBUG_DSOUND
         ds->played += audio_ring_dist (ds->old_pos, ppos, hw->bufsize);
 #endif
         old_pos = ds->old_pos;
     }

     if ((old_pos < ppos) && ((old_pos + len) > ppos)) {
         len = ppos - old_pos;
     }
     else {
         if ((old_pos > ppos) && ((old_pos + len) > (ppos + bufsize))) {
             len = bufsize - old_pos + ppos;
         }
     }

     if (audio_bug(__func__, len < 0 || len > bufsize)) {
         dolog ("len=%d bufsize=%d old_pos=%ld ppos=%ld\n",
                len, bufsize, old_pos, ppos);
         return 0;
     }

     len &= ~hw->info.align;
     if (!len) {
         return 0;
     }

 #ifdef DEBUG_DSOUND
     ds->old_ppos = ppos;
 #endif
     err = dsound_lock_out (
         dsb,
         &hw->info,
         old_pos,
         len,
         &p1, &p2,
         &blen1, &blen2,
         0,
         s
         );
     if (err) {
         return 0;
     }

     len1 = blen1 >> hwshift;
     len2 = blen2 >> hwshift;
     decr = len1 + len2;

     if (p1 && len1) {
         dsound_write_sample (hw, p1, len1);
     }

     if (p2 && len2) {
         dsound_write_sample (hw, p2, len2);
     }

     dsound_unlock_out (dsb, p1, p2, blen1, blen2);
     ds->old_pos = (old_pos + (decr << hwshift)) % bufsize;

 #ifdef DEBUG_DSOUND
     ds->mixed += decr << hwshift;

     dolog ("played %lu mixed %lu diff %ld sec %f\n",
            ds->played,
            ds->mixed,
            ds->mixed - ds->played,
            abs (ds->mixed - ds->played) / (double) hw->info.bytes_per_second);
 #endif
     return decr;
 }

 static int dsound_ctl_in (HWVoiceIn *hw, int cmd, ...)
 {
     HRESULT hr;
     DWORD status;
     DSoundVoiceIn *ds = (DSoundVoiceIn *) hw;
     LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;

     if (!dscb) {
         dolog ("Attempt to control capture voice without a buffer\n");
         return -1;
     }

     switch (cmd) {
     case VOICE_ENABLE:
         if (dsound_get_status_in (dscb, &status)) {
             return -1;
         }

         if (status & DSCBSTATUS_CAPTURING) {
             dolog ("warning: Voice is already capturing\n");
             return 0;
         }

         /* clear ?? */

         hr = IDirectSoundCaptureBuffer_Start (dscb, DSCBSTART_LOOPING);
         if (FAILED (hr)) {
             dsound_logerr (hr, "Could not start capturing\n");
             return -1;
         }
         break;

     case VOICE_DISABLE:
         if (dsound_get_status_in (dscb, &status)) {
             return -1;
         }

         if (status & DSCBSTATUS_CAPTURING) {
             hr = IDirectSoundCaptureBuffer_Stop (dscb);
             if (FAILED (hr)) {
                 dsound_logerr (hr, "Could not stop capturing\n");
                 return -1;
             }
         }
         else {
             dolog ("warning: Voice is not capturing\n");
         }
         break;
     }
     return 0;
 }

 static int dsound_read (SWVoiceIn *sw, void *buf, int len)
 {
     return audio_pcm_sw_read (sw, buf, len);
 }

 static int dsound_run_in (HWVoiceIn *hw)
 {
     int err;
     HRESULT hr;
     DSoundVoiceIn *ds = (DSoundVoiceIn *) hw;
     LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;
     int live, len, dead;
     DWORD blen1, blen2;
     DWORD len1, len2;
     DWORD decr;
     DWORD cpos, rpos;
     LPVOID p1, p2;
     int hwshift;
     dsound *s = ds->s;

     if (!dscb) {
         dolog ("Attempt to run without capture buffer\n");
         return 0;
     }

     hwshift = hw->info.shift;

     live = audio_pcm_hw_get_live_in (hw);
     dead = hw->samples - live;
     if (!dead) {
         return 0;
     }

     hr = IDirectSoundCaptureBuffer_GetCurrentPosition (
         dscb,
         &cpos,
         ds->first_time ? &rpos : NULL
         );
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not get capture buffer position\n");
         return 0;
     }

     if (ds->first_time) {
         ds->first_time = 0;
         if (rpos & hw->info.align) {
             ldebug ("warning: Misaligned capture read position %ld(%d)\n",
                     rpos, hw->info.align);
         }
         hw->wpos = rpos >> hwshift;
     }

     if (cpos & hw->info.align) {
         ldebug ("warning: Misaligned capture position %ld(%d)\n",
                 cpos, hw->info.align);
     }
     cpos >>= hwshift;

     len = audio_ring_dist (cpos, hw->wpos, hw->samples);
     if (!len) {
         return 0;
     }
     len = audio_MIN (len, dead);

     err = dsound_lock_in (
         dscb,
         &hw->info,
         hw->wpos << hwshift,
         len << hwshift,
         &p1,
         &p2,
         &blen1,
         &blen2,
         0,
         s
         );
     if (err) {
         return 0;
     }

     len1 = blen1 >> hwshift;
     len2 = blen2 >> hwshift;
     decr = len1 + len2;

     if (p1 && len1) {
         hw->conv (hw->conv_buf + hw->wpos, p1, len1);
     }

     if (p2 && len2) {
         hw->conv (hw->conv_buf, p2, len2);
     }

     dsound_unlock_in (dscb, p1, p2, blen1, blen2);
     hw->wpos = (hw->wpos + decr) % hw->samples;
     return decr;
 }

 static void dsound_audio_fini (void *opaque)
 {
     HRESULT hr;
     dsound *s = opaque;

     if (!s->dsound) {
         g_free(s);
         return;
     }

     hr = IDirectSound_Release (s->dsound);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not release DirectSound\n");
     }
     s->dsound = NULL;

     if (!s->dsound_capture) {
         g_free(s);
         return;
     }

     hr = IDirectSoundCapture_Release (s->dsound_capture);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not release DirectSoundCapture\n");
     }
     s->dsound_capture = NULL;

     g_free(s);
 }

 static void *dsound_audio_init(Audiodev *dev)
 {
     int err;
     HRESULT hr;
     dsound *s = g_malloc0(sizeof(dsound));
     AudiodevDsoundOptions *dso;

     assert(dev->driver == AUDIODEV_DRIVER_DSOUND);
     s->dev = dev;
     dso = &dev->u.dsound;

     if (!dso->has_latency) {
         dso->has_latency = true;
         dso->latency = 10000; /* 10 ms */
     }

     hr = CoInitialize (NULL);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not initialize COM\n");
         g_free(s);
         return NULL;
     }

     hr = CoCreateInstance (
         &CLSID_DirectSound,
         NULL,
         CLSCTX_ALL,
         &IID_IDirectSound,
         (void **) &s->dsound
         );
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not create DirectSound instance\n");
         g_free(s);
         return NULL;
     }

     hr = IDirectSound_Initialize (s->dsound, NULL);
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not initialize DirectSound\n");

         hr = IDirectSound_Release (s->dsound);
         if (FAILED (hr)) {
             dsound_logerr (hr, "Could not release DirectSound\n");
         }
         g_free(s);
         return NULL;
     }

     hr = CoCreateInstance (
         &CLSID_DirectSoundCapture,
         NULL,
         CLSCTX_ALL,
         &IID_IDirectSoundCapture,
         (void **) &s->dsound_capture
         );
     if (FAILED (hr)) {
         dsound_logerr (hr, "Could not create DirectSoundCapture instance\n");
     }
     else {
         hr = IDirectSoundCapture_Initialize (s->dsound_capture, NULL);
         if (FAILED (hr)) {
             dsound_logerr (hr, "Could not initialize DirectSoundCapture\n");

             hr = IDirectSoundCapture_Release (s->dsound_capture);
             if (FAILED (hr)) {
                 dsound_logerr (hr, "Could not release DirectSoundCapture\n");
             }
             s->dsound_capture = NULL;
         }
     }

     err = dsound_open (s);
     if (err) {
         dsound_audio_fini (s);
         return NULL;
     }

     return s;
 }

 static struct audio_pcm_ops dsound_pcm_ops = {
     .init_out = dsound_init_out,
     .fini_out = dsound_fini_out,
     .run_out  = dsound_run_out,
     .write    = dsound_write,
     .ctl_out  = dsound_ctl_out,

     .init_in  = dsound_init_in,
     .fini_in  = dsound_fini_in,
     .run_in   = dsound_run_in,
     .read     = dsound_read,
     .ctl_in   = dsound_ctl_in
 };

 static struct audio_driver dsound_audio_driver = {
     .name           = "dsound",
     .descr          = "DirectSound http://wikipedia.org/wiki/DirectSound",
     .init           = dsound_audio_init,
     .fini           = dsound_audio_fini,
     .pcm_ops        = &dsound_pcm_ops,
     .can_be_default = 1,
     .max_voices_out = INT_MAX,
     .max_voices_in  = 1,
     .voice_size_out = sizeof (DSoundVoiceOut),
     .voice_size_in  = sizeof (DSoundVoiceIn)
 };

 static void register_audio_dsound(void)
 {
     audio_driver_register(&dsound_audio_driver);
 }
 type_init(register_audio_dsound);
	/*
	* QEMU DirectSound audio driver
	*
	* Copyright (c) 2005 Vassili Karpov (malc)
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	/*
	* SEAL 1.07 by Carlos 'pel' Hasan was used as documentation
	*/

	#include "qemu/osdep.h"
	#include "qemu-common.h"
	#include "audio.h"

	#define AUDIO_CAP "dsound"
	#include "audio_int.h"
	#include "qemu/host-utils.h"

	#include <windows.h>
	#include <mmsystem.h>
	#include <objbase.h>
	#include <dsound.h>

	#include "audio_win_int.h"

	/* #define DEBUG_DSOUND */

	typedef struct {
	LPDIRECTSOUND dsound;
	LPDIRECTSOUNDCAPTURE dsound_capture;
	struct audsettings settings;
	Audiodev *dev;
	} dsound;

	typedef struct {
	HWVoiceOut hw;
	LPDIRECTSOUNDBUFFER dsound_buffer;
	DWORD old_pos;
	int first_time;
	dsound *s;
	#ifdef DEBUG_DSOUND
	DWORD old_ppos;
	DWORD played;
	DWORD mixed;
	#endif
	} DSoundVoiceOut;

	typedef struct {
	HWVoiceIn hw;
	int first_time;
	LPDIRECTSOUNDCAPTUREBUFFER dsound_capture_buffer;
	dsound *s;
	} DSoundVoiceIn;

	static void dsound_log_hresult (HRESULT hr)
	{
	const char *str = "BUG";

	switch (hr) {
	case DS_OK:
	str = "The method succeeded";
	break;
	#ifdef DS_NO_VIRTUALIZATION
	case DS_NO_VIRTUALIZATION:
	str = "The buffer was created, but another 3D algorithm was substituted";
	break;
	#endif
	#ifdef DS_INCOMPLETE
	case DS_INCOMPLETE:
	str = "The method succeeded, but not all the optional effects were obtained";
	break;
	#endif
	#ifdef DSERR_ACCESSDENIED
	case DSERR_ACCESSDENIED:
	str = "The request failed because access was denied";
	break;
	#endif
	#ifdef DSERR_ALLOCATED
	case DSERR_ALLOCATED:
	str = "The request failed because resources, such as a priority level, were already in use by another caller";
	break;
	#endif
	#ifdef DSERR_ALREADYINITIALIZED
	case DSERR_ALREADYINITIALIZED:
	str = "The object is already initialized";
	break;
	#endif
	#ifdef DSERR_BADFORMAT
	case DSERR_BADFORMAT:
	str = "The specified wave format is not supported";
	break;
	#endif
	#ifdef DSERR_BADSENDBUFFERGUID
	case DSERR_BADSENDBUFFERGUID:
	str = "The GUID specified in an audiopath file does not match a valid mix-in buffer";
	break;
	#endif
	#ifdef DSERR_BUFFERLOST
	case DSERR_BUFFERLOST:
	str = "The buffer memory has been lost and must be restored";
	break;
	#endif
	#ifdef DSERR_BUFFERTOOSMALL
	case DSERR_BUFFERTOOSMALL:
	str = "The buffer size is not great enough to enable effects processing";
	break;
	#endif
	#ifdef DSERR_CONTROLUNAVAIL
	case DSERR_CONTROLUNAVAIL:
	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";
	break;
	#endif
	#ifdef DSERR_DS8_REQUIRED
	case DSERR_DS8_REQUIRED:
	str = "A DirectSound object of class CLSID_DirectSound8 or later is required for the requested functionality. For more information, see IDirectSound8 Interface";
	break;
	#endif
	#ifdef DSERR_FXUNAVAILABLE
	case DSERR_FXUNAVAILABLE:
	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";
	break;
	#endif
	#ifdef DSERR_GENERIC
	case DSERR_GENERIC :
	str = "An undetermined error occurred inside the DirectSound subsystem";
	break;
	#endif
	#ifdef DSERR_INVALIDCALL
	case DSERR_INVALIDCALL:
	str = "This function is not valid for the current state of this object";
	break;
	#endif
	#ifdef DSERR_INVALIDPARAM
	case DSERR_INVALIDPARAM:
	str = "An invalid parameter was passed to the returning function";
	break;
	#endif
	#ifdef DSERR_NOAGGREGATION
	case DSERR_NOAGGREGATION:
	str = "The object does not support aggregation";
	break;
	#endif
	#ifdef DSERR_NODRIVER
	case DSERR_NODRIVER:
	str = "No sound driver is available for use, or the given GUID is not a valid DirectSound device ID";
	break;
	#endif
	#ifdef DSERR_NOINTERFACE
	case DSERR_NOINTERFACE:
	str = "The requested COM interface is not available";
	break;
	#endif
	#ifdef DSERR_OBJECTNOTFOUND
	case DSERR_OBJECTNOTFOUND:
	str = "The requested object was not found";
	break;
	#endif
	#ifdef DSERR_OTHERAPPHASPRIO
	case DSERR_OTHERAPPHASPRIO:
	str = "Another application has a higher priority level, preventing this call from succeeding";
	break;
	#endif
	#ifdef DSERR_OUTOFMEMORY
	case DSERR_OUTOFMEMORY:
	str = "The DirectSound subsystem could not allocate sufficient memory to complete the caller's request";
	break;
	#endif
	#ifdef DSERR_PRIOLEVELNEEDED
	case DSERR_PRIOLEVELNEEDED:
	str = "A cooperative level of DSSCL_PRIORITY or higher is required";
	break;
	#endif
	#ifdef DSERR_SENDLOOP
	case DSERR_SENDLOOP:
	str = "A circular loop of send effects was detected";
	break;
	#endif
	#ifdef DSERR_UNINITIALIZED
	case DSERR_UNINITIALIZED:
	str = "The Initialize method has not been called or has not been called successfully before other methods were called";
	break;
	#endif
	#ifdef DSERR_UNSUPPORTED
	case DSERR_UNSUPPORTED:
	str = "The function called is not supported at this time";
	break;
	#endif
	default:
	AUD_log (AUDIO_CAP, "Reason: Unknown (HRESULT %#lx)\n", hr);
	return;
	}

	AUD_log (AUDIO_CAP, "Reason: %s\n", str);
	}

	static void GCC_FMT_ATTR (2, 3) dsound_logerr (
	HRESULT hr,
	const char *fmt,
	...
	)
	{
	va_list ap;

	va_start (ap, fmt);
	AUD_vlog (AUDIO_CAP, fmt, ap);
	va_end (ap);

	dsound_log_hresult (hr);
	}

	static void GCC_FMT_ATTR (3, 4) dsound_logerr2 (
	HRESULT hr,
	const char *typ,
	const char *fmt,
	...
	)
	{
	va_list ap;

	AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
	va_start (ap, fmt);
	AUD_vlog (AUDIO_CAP, fmt, ap);
	va_end (ap);

	dsound_log_hresult (hr);
	}

	static uint64_t usecs_to_bytes(struct audio_pcm_info *info, uint32_t usecs)
	{
	return muldiv64(usecs, info->bytes_per_second, 1000000);
	}

	#ifdef DEBUG_DSOUND
	static void print_wave_format (WAVEFORMATEX *wfx)
	{
	dolog ("tag = %d\n", wfx->wFormatTag);
	dolog ("nChannels = %d\n", wfx->nChannels);
	dolog ("nSamplesPerSec = %ld\n", wfx->nSamplesPerSec);
	dolog ("nAvgBytesPerSec = %ld\n", wfx->nAvgBytesPerSec);
	dolog ("nBlockAlign = %d\n", wfx->nBlockAlign);
	dolog ("wBitsPerSample = %d\n", wfx->wBitsPerSample);
	dolog ("cbSize = %d\n", wfx->cbSize);
	}
	#endif

	static int dsound_restore_out (LPDIRECTSOUNDBUFFER dsb, dsound *s)
	{
	HRESULT hr;

	hr = IDirectSoundBuffer_Restore (dsb);

	if (hr != DS_OK) {
	dsound_logerr (hr, "Could not restore playback buffer\n");
	return -1;
	}
	return 0;
	}

	#include "dsound_template.h"
	#define DSBTYPE_IN
	#include "dsound_template.h"
	#undef DSBTYPE_IN

	static int dsound_get_status_out (LPDIRECTSOUNDBUFFER dsb, DWORD *statusp,
	dsound *s)
	{
	HRESULT hr;

	hr = IDirectSoundBuffer_GetStatus (dsb, statusp);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not get playback buffer status\n");
	return -1;
	}

	if (*statusp & DSERR_BUFFERLOST) {
	dsound_restore_out(dsb, s);
	return -1;
	}

	return 0;
	}

	static int dsound_get_status_in (LPDIRECTSOUNDCAPTUREBUFFER dscb,
	DWORD *statusp)
	{
	HRESULT hr;

	hr = IDirectSoundCaptureBuffer_GetStatus (dscb, statusp);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not get capture buffer status\n");
	return -1;
	}

	return 0;
	}

	static void dsound_write_sample (HWVoiceOut hw, uint8_t dst, int dst_len)
	{
	int src_len1 = dst_len;
	int src_len2 = 0;
	int pos = hw->rpos + dst_len;
	struct st_sample *src1 = hw->mix_buf + hw->rpos;
	struct st_sample *src2 = NULL;

	if (pos > hw->samples) {
	src_len1 = hw->samples - hw->rpos;
	src2 = hw->mix_buf;
	src_len2 = dst_len - src_len1;
	pos = src_len2;
	}

	if (src_len1) {
	hw->clip (dst, src1, src_len1);
	}

	if (src_len2) {
	dst = advance (dst, src_len1 << hw->info.shift);
	hw->clip (dst, src2, src_len2);
	}

	hw->rpos = pos % hw->samples;
	}

	static void dsound_clear_sample (HWVoiceOut *hw, LPDIRECTSOUNDBUFFER dsb,
	dsound *s)
	{
	int err;
	LPVOID p1, p2;
	DWORD blen1, blen2, len1, len2;

	err = dsound_lock_out (
	dsb,
	&hw->info,
	0,
	hw->samples << hw->info.shift,
	&p1, &p2,
	&blen1, &blen2,
	1,
	s
	);
	if (err) {
	return;
	}

	len1 = blen1 >> hw->info.shift;
	len2 = blen2 >> hw->info.shift;

	#ifdef DEBUG_DSOUND
	dolog ("clear %p,%ld,%ld %p,%ld,%ld\n",
	p1, blen1, len1,
	p2, blen2, len2);
	#endif

	if (p1 && len1) {
	audio_pcm_info_clear_buf (&hw->info, p1, len1);
	}

	if (p2 && len2) {
	audio_pcm_info_clear_buf (&hw->info, p2, len2);
	}

	dsound_unlock_out (dsb, p1, p2, blen1, blen2);
	}

	static int dsound_open (dsound *s)
	{
	HRESULT hr;
	HWND hwnd;

	hwnd = GetForegroundWindow ();
	hr = IDirectSound_SetCooperativeLevel (
	s->dsound,
	hwnd,
	DSSCL_PRIORITY
	);

	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not set cooperative level for window %p\n",
	hwnd);
	return -1;
	}

	return 0;
	}

	static int dsound_ctl_out (HWVoiceOut *hw, int cmd, ...)
	{
	HRESULT hr;
	DWORD status;
	DSoundVoiceOut ds = (DSoundVoiceOut ) hw;
	LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
	dsound *s = ds->s;

	if (!dsb) {
	dolog ("Attempt to control voice without a buffer\n");
	return 0;
	}

	switch (cmd) {
	case VOICE_ENABLE:
	if (dsound_get_status_out (dsb, &status, s)) {
	return -1;
	}

	if (status & DSBSTATUS_PLAYING) {
	dolog ("warning: Voice is already playing\n");
	return 0;
	}

	dsound_clear_sample (hw, dsb, s);

	hr = IDirectSoundBuffer_Play (dsb, 0, 0, DSBPLAY_LOOPING);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not start playing buffer\n");
	return -1;
	}
	break;

	case VOICE_DISABLE:
	if (dsound_get_status_out (dsb, &status, s)) {
	return -1;
	}

	if (status & DSBSTATUS_PLAYING) {
	hr = IDirectSoundBuffer_Stop (dsb);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not stop playing buffer\n");
	return -1;
	}
	}
	else {
	dolog ("warning: Voice is not playing\n");
	}
	break;
	}
	return 0;
	}

	static int dsound_write (SWVoiceOut sw, void buf, int len)
	{
	return audio_pcm_sw_write (sw, buf, len);
	}

	static int dsound_run_out (HWVoiceOut *hw, int live)
	{
	int err;
	HRESULT hr;
	DSoundVoiceOut ds = (DSoundVoiceOut ) hw;
	LPDIRECTSOUNDBUFFER dsb = ds->dsound_buffer;
	int len, hwshift;
	DWORD blen1, blen2;
	DWORD len1, len2;
	DWORD decr;
	DWORD wpos, ppos, old_pos;
	LPVOID p1, p2;
	int bufsize;
	dsound *s = ds->s;
	AudiodevDsoundOptions *dso = &s->dev->u.dsound;

	if (!dsb) {
	dolog ("Attempt to run empty with playback buffer\n");
	return 0;
	}

	hwshift = hw->info.shift;
	bufsize = hw->samples << hwshift;

	hr = IDirectSoundBuffer_GetCurrentPosition (
	dsb,
	&ppos,
	ds->first_time ? &wpos : NULL
	);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not get playback buffer position\n");
	return 0;
	}

	len = live << hwshift;

	if (ds->first_time) {
	if (dso->latency) {
	DWORD cur_blat;

	cur_blat = audio_ring_dist (wpos, ppos, bufsize);
	ds->first_time = 0;
	old_pos = wpos;
	old_pos +=
	usecs_to_bytes(&hw->info, dso->latency) - cur_blat;
	old_pos %= bufsize;
	old_pos &= ~hw->info.align;
	}
	else {
	old_pos = wpos;
	}
	#ifdef DEBUG_DSOUND
	ds->played = 0;
	ds->mixed = 0;
	#endif
	}
	else {
	if (ds->old_pos == ppos) {
	#ifdef DEBUG_DSOUND
	dolog ("old_pos == ppos\n");
	#endif
	return 0;
	}

	#ifdef DEBUG_DSOUND
	ds->played += audio_ring_dist (ds->old_pos, ppos, hw->bufsize);
	#endif
	old_pos = ds->old_pos;
	}

	if ((old_pos < ppos) && ((old_pos + len) > ppos)) {
	len = ppos - old_pos;
	}
	else {
	if ((old_pos > ppos) && ((old_pos + len) > (ppos + bufsize))) {
	len = bufsize - old_pos + ppos;
	}
	}

	if (audio_bug(__func__, len < 0 \|\| len > bufsize)) {
	dolog ("len=%d bufsize=%d old_pos=%ld ppos=%ld\n",
	len, bufsize, old_pos, ppos);
	return 0;
	}

	len &= ~hw->info.align;
	if (!len) {
	return 0;
	}

	#ifdef DEBUG_DSOUND
	ds->old_ppos = ppos;
	#endif
	err = dsound_lock_out (
	dsb,
	&hw->info,
	old_pos,
	len,
	&p1, &p2,
	&blen1, &blen2,
	0,
	s
	);
	if (err) {
	return 0;
	}

	len1 = blen1 >> hwshift;
	len2 = blen2 >> hwshift;
	decr = len1 + len2;

	if (p1 && len1) {
	dsound_write_sample (hw, p1, len1);
	}

	if (p2 && len2) {
	dsound_write_sample (hw, p2, len2);
	}

	dsound_unlock_out (dsb, p1, p2, blen1, blen2);
	ds->old_pos = (old_pos + (decr << hwshift)) % bufsize;

	#ifdef DEBUG_DSOUND
	ds->mixed += decr << hwshift;

	dolog ("played %lu mixed %lu diff %ld sec %f\n",
	ds->played,
	ds->mixed,
	ds->mixed - ds->played,
	abs (ds->mixed - ds->played) / (double) hw->info.bytes_per_second);
	#endif
	return decr;
	}

	static int dsound_ctl_in (HWVoiceIn *hw, int cmd, ...)
	{
	HRESULT hr;
	DWORD status;
	DSoundVoiceIn ds = (DSoundVoiceIn ) hw;
	LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;

	if (!dscb) {
	dolog ("Attempt to control capture voice without a buffer\n");
	return -1;
	}

	switch (cmd) {
	case VOICE_ENABLE:
	if (dsound_get_status_in (dscb, &status)) {
	return -1;
	}

	if (status & DSCBSTATUS_CAPTURING) {
	dolog ("warning: Voice is already capturing\n");
	return 0;
	}

	/* clear ?? */

	hr = IDirectSoundCaptureBuffer_Start (dscb, DSCBSTART_LOOPING);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not start capturing\n");
	return -1;
	}
	break;

	case VOICE_DISABLE:
	if (dsound_get_status_in (dscb, &status)) {
	return -1;
	}

	if (status & DSCBSTATUS_CAPTURING) {
	hr = IDirectSoundCaptureBuffer_Stop (dscb);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not stop capturing\n");
	return -1;
	}
	}
	else {
	dolog ("warning: Voice is not capturing\n");
	}
	break;
	}
	return 0;
	}

	static int dsound_read (SWVoiceIn sw, void buf, int len)
	{
	return audio_pcm_sw_read (sw, buf, len);
	}

	static int dsound_run_in (HWVoiceIn *hw)
	{
	int err;
	HRESULT hr;
	DSoundVoiceIn ds = (DSoundVoiceIn ) hw;
	LPDIRECTSOUNDCAPTUREBUFFER dscb = ds->dsound_capture_buffer;
	int live, len, dead;
	DWORD blen1, blen2;
	DWORD len1, len2;
	DWORD decr;
	DWORD cpos, rpos;
	LPVOID p1, p2;
	int hwshift;
	dsound *s = ds->s;

	if (!dscb) {
	dolog ("Attempt to run without capture buffer\n");
	return 0;
	}

	hwshift = hw->info.shift;

	live = audio_pcm_hw_get_live_in (hw);
	dead = hw->samples - live;
	if (!dead) {
	return 0;
	}

	hr = IDirectSoundCaptureBuffer_GetCurrentPosition (
	dscb,
	&cpos,
	ds->first_time ? &rpos : NULL
	);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not get capture buffer position\n");
	return 0;
	}

	if (ds->first_time) {
	ds->first_time = 0;
	if (rpos & hw->info.align) {
	ldebug ("warning: Misaligned capture read position %ld(%d)\n",
	rpos, hw->info.align);
	}
	hw->wpos = rpos >> hwshift;
	}

	if (cpos & hw->info.align) {
	ldebug ("warning: Misaligned capture position %ld(%d)\n",
	cpos, hw->info.align);
	}
	cpos >>= hwshift;

	len = audio_ring_dist (cpos, hw->wpos, hw->samples);
	if (!len) {
	return 0;
	}
	len = audio_MIN (len, dead);

	err = dsound_lock_in (
	dscb,
	&hw->info,
	hw->wpos << hwshift,
	len << hwshift,
	&p1,
	&p2,
	&blen1,
	&blen2,
	0,
	s
	);
	if (err) {
	return 0;
	}

	len1 = blen1 >> hwshift;
	len2 = blen2 >> hwshift;
	decr = len1 + len2;

	if (p1 && len1) {
	hw->conv (hw->conv_buf + hw->wpos, p1, len1);
	}

	if (p2 && len2) {
	hw->conv (hw->conv_buf, p2, len2);
	}

	dsound_unlock_in (dscb, p1, p2, blen1, blen2);
	hw->wpos = (hw->wpos + decr) % hw->samples;
	return decr;
	}

	static void dsound_audio_fini (void *opaque)
	{
	HRESULT hr;
	dsound *s = opaque;

	if (!s->dsound) {
	g_free(s);
	return;
	}

	hr = IDirectSound_Release (s->dsound);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not release DirectSound\n");
	}
	s->dsound = NULL;

	if (!s->dsound_capture) {
	g_free(s);
	return;
	}

	hr = IDirectSoundCapture_Release (s->dsound_capture);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not release DirectSoundCapture\n");
	}
	s->dsound_capture = NULL;

	g_free(s);
	}

	static void dsound_audio_init(Audiodev dev)
	{
	int err;
	HRESULT hr;
	dsound *s = g_malloc0(sizeof(dsound));
	AudiodevDsoundOptions *dso;

	assert(dev->driver == AUDIODEV_DRIVER_DSOUND);
	s->dev = dev;
	dso = &dev->u.dsound;

	if (!dso->has_latency) {
	dso->has_latency = true;
	dso->latency = 10000; /* 10 ms */
	}

	hr = CoInitialize (NULL);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not initialize COM\n");
	g_free(s);
	return NULL;
	}

	hr = CoCreateInstance (
	&CLSID_DirectSound,
	NULL,
	CLSCTX_ALL,
	&IID_IDirectSound,
	(void **) &s->dsound
	);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not create DirectSound instance\n");
	g_free(s);
	return NULL;
	}

	hr = IDirectSound_Initialize (s->dsound, NULL);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not initialize DirectSound\n");

	hr = IDirectSound_Release (s->dsound);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not release DirectSound\n");
	}
	g_free(s);
	return NULL;
	}

	hr = CoCreateInstance (
	&CLSID_DirectSoundCapture,
	NULL,
	CLSCTX_ALL,
	&IID_IDirectSoundCapture,
	(void **) &s->dsound_capture
	);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not create DirectSoundCapture instance\n");
	}
	else {
	hr = IDirectSoundCapture_Initialize (s->dsound_capture, NULL);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not initialize DirectSoundCapture\n");

	hr = IDirectSoundCapture_Release (s->dsound_capture);
	if (FAILED (hr)) {
	dsound_logerr (hr, "Could not release DirectSoundCapture\n");
	}
	s->dsound_capture = NULL;
	}
	}

	err = dsound_open (s);
	if (err) {
	dsound_audio_fini (s);
	return NULL;
	}

	return s;
	}

	static struct audio_pcm_ops dsound_pcm_ops = {
	.init_out = dsound_init_out,
	.fini_out = dsound_fini_out,
	.run_out = dsound_run_out,
	.write = dsound_write,
	.ctl_out = dsound_ctl_out,

	.init_in = dsound_init_in,
	.fini_in = dsound_fini_in,
	.run_in = dsound_run_in,
	.read = dsound_read,
	.ctl_in = dsound_ctl_in
	};

	static struct audio_driver dsound_audio_driver = {
	.name = "dsound",
	.descr = "DirectSound http://wikipedia.org/wiki/DirectSound",
	.init = dsound_audio_init,
	.fini = dsound_audio_fini,
	.pcm_ops = &dsound_pcm_ops,
	.can_be_default = 1,
	.max_voices_out = INT_MAX,
	.max_voices_in = 1,
	.voice_size_out = sizeof (DSoundVoiceOut),
	.voice_size_in = sizeof (DSoundVoiceIn)
	};

	static void register_audio_dsound(void)
	{
	audio_driver_register(&dsound_audio_driver);
	}
	type_init(register_audio_dsound);