src/audio/qsa/SDL_qsa_audio.c

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org

    QNX Sound Architecture (QSA) SDL driver
    Copyright (C) 2009 Mike Gorchak
    (mike@malva.ua, lestat@i.com.ua)
*/

#include "SDL_config.h"

#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sched.h>
#include <sys/select.h>
#include <sys/neutrino.h>
#include <sys/asoundlib.h>

#include "SDL_timer.h"
#include "SDL_audio.h"
#include "../SDL_audiomem.h"
#include "../SDL_audio_c.h"
#include "SDL_qsa_audio.h"

/* The tag name used by QSA audio framework */
#define DRIVER_NAME "qsa"

/* default channel communication parameters */
#define DEFAULT_CPARAMS_RATE   44100
#define DEFAULT_CPARAMS_VOICES 1

#define DEFAULT_CPARAMS_FRAG_SIZE 4096
#define DEFAULT_CPARAMS_FRAGS_MIN 1
#define DEFAULT_CPARAMS_FRAGS_MAX 1

#define QSA_NO_WORKAROUNDS  0x00000000
#define QSA_MMAP_WORKAROUND 0x00000001

struct BuggyCards
{
    char* cardname;
    unsigned long bugtype;
};

#define QSA_WA_CARDS             3
#define QSA_MAX_CARD_NAME_LENGTH 33

struct BuggyCards buggycards[QSA_WA_CARDS]=
{
   {"Sound Blaster Live!", QSA_MMAP_WORKAROUND},
   {"Vortex 8820", QSA_MMAP_WORKAROUND},
   {"Vortex 8830", QSA_MMAP_WORKAROUND},
};

/* List of found devices */
#define QSA_MAX_DEVICES       32
#define QSA_MAX_NAME_LENGTH   81+16 /* Hardcoded in QSA, can't be changed */

typedef struct _QSA_Device
{
   char  name[QSA_MAX_NAME_LENGTH];   /* Long audio device name for SDL  */
   int   cardno;
   int   deviceno;
} QSA_Device;

QSA_Device qsa_playback_device[QSA_MAX_DEVICES];
uint32_t   qsa_playback_devices;

QSA_Device qsa_capture_device[QSA_MAX_DEVICES];
uint32_t   qsa_capture_devices;

static inline void QSA_SetError(const char* fn, int status)
{
   SDL_SetError("QSA: %s() failed: %s", fn, snd_strerror(status));
}

/* card names check to apply the workarounds */
static int QSA_CheckBuggyCards(_THIS, unsigned long checkfor)
{
   char scardname[QSA_MAX_CARD_NAME_LENGTH];
   int it;

   if (snd_card_get_name(this->hidden->cardno, scardname, QSA_MAX_CARD_NAME_LENGTH-1)<0)
   {
      return 0;
   }

   for (it=0; it<QSA_WA_CARDS; it++)
   {
      if (SDL_strcmp(buggycards[it].cardname, scardname)==0)
      {
         if (buggycards[it].bugtype==checkfor)
         {
            return 1;
         }
      }
   }

   return 0;
}

static void QSA_ThreadInit(_THIS)
{
   struct sched_param param;
   int status;

   /* Increase default 10 priority to 25 to avoid jerky sound */
   status=SchedGet(0, 0, &param);
   param.sched_priority=param.sched_curpriority + 15;
   status=SchedSet(0, 0, SCHED_NOCHANGE, &param);
}

/* PCM channel parameters initialize function */
static void QSA_InitAudioParams(snd_pcm_channel_params_t* cpars)
{
   SDL_memset(cpars, 0, sizeof(snd_pcm_channel_params_t));

   cpars->channel=SND_PCM_CHANNEL_PLAYBACK;
   cpars->mode=SND_PCM_MODE_BLOCK;
   cpars->start_mode=SND_PCM_START_DATA;
   cpars->stop_mode=SND_PCM_STOP_STOP;
   cpars->format.format=SND_PCM_SFMT_S16_LE;
   cpars->format.interleave=1;
   cpars->format.rate=DEFAULT_CPARAMS_RATE;
   cpars->format.voices=DEFAULT_CPARAMS_VOICES;
   cpars->buf.block.frag_size=DEFAULT_CPARAMS_FRAG_SIZE;
   cpars->buf.block.frags_min=DEFAULT_CPARAMS_FRAGS_MIN;
   cpars->buf.block.frags_max=DEFAULT_CPARAMS_FRAGS_MAX;
}

/* This function waits until it is possible to write a full sound buffer */
static void QSA_WaitDevice(_THIS)
{
   fd_set wfds;
   fd_set rfds;
   int selectret;
   struct timeval timeout;

   if (!this->hidden->iscapture)
   {
      FD_ZERO(&wfds);
      FD_SET(this->hidden->audio_fd, &wfds);
   }
   else
   {
      FD_ZERO(&rfds);
      FD_SET(this->hidden->audio_fd, &rfds);
   }

   do {
      /* Setup timeout for playing one fragment equal to 2 seconds          */
      /* If timeout occured than something wrong with hardware or driver    */
      /* For example, Vortex 8820 audio driver stucks on second DAC because */
      /* it doesn't exist !                                                 */
      timeout.tv_sec=2;
      timeout.tv_usec=0;
      this->hidden->timeout_on_wait=0;

      if (!this->hidden->iscapture)
      {
         selectret=select(this->hidden->audio_fd+1, NULL, &wfds, NULL, &timeout);
      }
      else
      {
         selectret=select(this->hidden->audio_fd+1, &rfds, NULL, NULL, &timeout);
      }

      switch(selectret)
      {
         case -1:
              {
                 SDL_SetError("QSA: select() failed: %s\n", strerror(errno));
                 return;
              }
              break;
         case 0:
              {
                 SDL_SetError("QSA: timeout on buffer waiting occured\n");
                 this->hidden->timeout_on_wait=1;
                 return;
              }
              break;
         default:
              {
                 if (!this->hidden->iscapture)
                 {
                    if (FD_ISSET(this->hidden->audio_fd, &wfds))
                    {
                       return;
                    }
                 }
                 else
                 {
                    if (FD_ISSET(this->hidden->audio_fd, &rfds))
                    {
                       return;
                    }
                 }
              }
              break;
      }
   } while (1);
}

static void QSA_PlayDevice(_THIS)
{
   snd_pcm_channel_status_t cstatus;
   int   written;
   int   status;
   int   towrite;
   void* pcmbuffer;

   if ((!this->enabled) || (!this->hidden))
   {
      return;
   }

   towrite = this->spec.size;
   pcmbuffer = this->hidden->pcm_buf;

   /* Write the audio data, checking for EAGAIN (buffer full) and underrun */
   do {
      written=snd_pcm_plugin_write(this->hidden->audio_handle, pcmbuffer, towrite);
      if (written!=towrite)
      {
         /* Check if samples playback got stuck somewhere in hardware or in */
         /* the audio device driver */
         if ((errno==EAGAIN) && (written==0))
         {
            if (this->hidden->timeout_on_wait!=0)
            {
               SDL_SetError("QSA: buffer playback timeout\n");
               return;
            }
         }

         /* Check for errors or conditions */
         if ((errno==EAGAIN)||(errno==EWOULDBLOCK))
         {
            /* Let a little CPU time go by and try to write again */
            SDL_Delay(1);

            /* if we wrote some data */
            towrite-=written;
            pcmbuffer+=written*this->spec.channels;
            continue;
         }
         else
         {
            if ((errno==EINVAL)||(errno==EIO))
            {
               SDL_memset(&cstatus, 0, sizeof(cstatus));
               if (!this->hidden->iscapture)
               {
                  cstatus.channel=SND_PCM_CHANNEL_PLAYBACK;
               }
               else
               {
                  cstatus.channel=SND_PCM_CHANNEL_CAPTURE;
               }

               status=snd_pcm_plugin_status(this->hidden->audio_handle, &cstatus);
               if (status<0)
               {
                  QSA_SetError("snd_pcm_plugin_status", status);
                  return;
               }

               if ((cstatus.status==SND_PCM_STATUS_UNDERRUN) ||
                   (cstatus.status==SND_PCM_STATUS_READY))
               {
                  if (!this->hidden->iscapture)
                  {
                     status=snd_pcm_plugin_prepare(this->hidden->audio_handle,
                                                   SND_PCM_CHANNEL_PLAYBACK);
                  }
                  else
                  {
                     status=snd_pcm_plugin_prepare(this->hidden->audio_handle,
                                                   SND_PCM_CHANNEL_CAPTURE);
                  }
                  if (status<0)
                  {
                     QSA_SetError("snd_pcm_plugin_prepare", status);
                     return;
                  }
               }
               continue;
            }
            else
            {
                return;
            }
         }
      }
      else
      {
         /* we wrote all remaining data */
         towrite -= written;
         pcmbuffer += written * this->spec.channels;
      }
   } while ((towrite>0) && (this->enabled));

   /* If we couldn't write, assume fatal error for now */
   if (towrite!=0)
   {
      this->enabled=0;
   }
}

static Uint8* QSA_GetDeviceBuf(_THIS)
{
   return this->hidden->pcm_buf;
}

static void QSA_CloseDevice(_THIS)
{
   if (this->hidden!=NULL)
   {
      if (this->hidden->audio_handle!=NULL)
      {
         if (!this->hidden->iscapture)
         {
            /* Finish playing available samples */
            snd_pcm_plugin_flush(this->hidden->audio_handle, SND_PCM_CHANNEL_PLAYBACK);
         }
         else
         {
            /* Cancel unread samples during capture */
            snd_pcm_plugin_flush(this->hidden->audio_handle, SND_PCM_CHANNEL_CAPTURE);
         }
         snd_pcm_close(this->hidden->audio_handle);
         this->hidden->audio_handle=NULL;
      }

      if (this->hidden->pcm_buf!=NULL)
      {
         SDL_FreeAudioMem(this->hidden->pcm_buf);
         this->hidden->pcm_buf=NULL;
      }

      SDL_free(this->hidden);
      this->hidden=NULL;
   }
}

static int QSA_OpenDevice(_THIS, const char* devname, int iscapture)
{
   int status=0;
   int format=0;
   SDL_AudioFormat test_format=0;
   int found=0;
   snd_pcm_channel_setup_t  csetup;
   snd_pcm_channel_params_t cparams;

   /* Initialize all variables that we clean on shutdown */
   this->hidden=(struct SDL_PrivateAudioData*)SDL_calloc(1, (sizeof(struct SDL_PrivateAudioData)));
   if (this->hidden==NULL)
   {
      SDL_OutOfMemory();
      return 0;
   }
   SDL_memset(this->hidden, 0, sizeof(struct SDL_PrivateAudioData));

   /* Initialize channel transfer parameters to default */
   QSA_InitAudioParams(&cparams);

   /* Initialize channel direction: capture or playback */
   this->hidden->iscapture=iscapture;

   /* Find deviceid and cardid by device name for playback */
   if ((!this->hidden->iscapture) && (devname!=NULL))
   {
      uint32_t device;
      int32_t  status;

      /* Search in the playback devices */
      device=0;
      do {
         status=SDL_strcmp(qsa_playback_device[device].name, devname);
         if (status==0)
         {
            /* Found requested device */
            this->hidden->deviceno=qsa_playback_device[device].deviceno;
            this->hidden->cardno=qsa_playback_device[device].cardno;
            break;
         }
         device++;
         if (device>=qsa_playback_devices)
         {
            QSA_CloseDevice(this);
            SDL_SetError("No such playback device");
            return 0;
         }
      } while(1);
   }

   /* Find deviceid and cardid by device name for capture */
   if ((this->hidden->iscapture) && (devname!=NULL))
   {
      /* Search in the capture devices */
      uint32_t device;
      int32_t  status;

      /* Searching in the playback devices */
      device=0;
      do {
         status=SDL_strcmp(qsa_capture_device[device].name, devname);
         if (status==0)
         {
            /* Found requested device */
            this->hidden->deviceno=qsa_capture_device[device].deviceno;
            this->hidden->cardno=qsa_capture_device[device].cardno;
            break;
         }
         device++;
         if (device>=qsa_capture_devices)
         {
            QSA_CloseDevice(this);
            SDL_SetError("No such capture device");
            return 0;
         }
      } while(1);
   }

   /* Check if SDL requested default audio device */
   if (devname==NULL)
   {
      /* Open system default audio device */
      if (!this->hidden->iscapture)
      {
         status=snd_pcm_open_preferred(&this->hidden->audio_handle,
                                       &this->hidden->cardno,
                                       &this->hidden->deviceno, SND_PCM_OPEN_PLAYBACK);
      }
      else
      {
         status=snd_pcm_open_preferred(&this->hidden->audio_handle,
                                       &this->hidden->cardno,
                                       &this->hidden->deviceno, SND_PCM_OPEN_CAPTURE);
      }
   }
   else
   {
      /* Open requested audio device */
      if (!this->hidden->iscapture)
      {
         status=snd_pcm_open(&this->hidden->audio_handle, this->hidden->cardno,
                              this->hidden->deviceno, SND_PCM_OPEN_PLAYBACK);
      }
      else
      {
         status=snd_pcm_open(&this->hidden->audio_handle, this->hidden->cardno,
                              this->hidden->deviceno, SND_PCM_OPEN_CAPTURE);
      }
   }

   /* Check if requested device is opened */
   if (status<0)
   {
      this->hidden->audio_handle=NULL;
      QSA_CloseDevice(this);
      QSA_SetError("snd_pcm_open", status);
      return 0;
   }

   if (!QSA_CheckBuggyCards(this, QSA_MMAP_WORKAROUND))
   {
      /* Disable QSA MMAP plugin for buggy audio drivers */
      status=snd_pcm_plugin_set_disable(this->hidden->audio_handle, PLUGIN_DISABLE_MMAP);
      if (status<0)
      {
         QSA_CloseDevice(this);
         QSA_SetError("snd_pcm_plugin_set_disable", status);
         return 0;
      }
   }

   /* Try for a closest match on audio format */
   format = 0;
   /* can't use format as SND_PCM_SFMT_U8 = 0 in qsa */
   found = 0;

   for (test_format = SDL_FirstAudioFormat(this->spec.format); !found;)
   {
      /* if match found set format to equivalent QSA format */
      switch (test_format)
      {
         case AUDIO_U8:
              {
                 format=SND_PCM_SFMT_U8;
                 found=1;
              }
              break;
         case AUDIO_S8:
              {
                 format=SND_PCM_SFMT_S8;
                 found=1;
              }
              break;
         case AUDIO_S16LSB:
              {
                 format=SND_PCM_SFMT_S16_LE;
                 found=1;
              }
              break;
         case AUDIO_S16MSB:
              {
                 format=SND_PCM_SFMT_S16_BE;
                 found=1;
              }
              break;
         case AUDIO_U16LSB:
              {
                 format=SND_PCM_SFMT_U16_LE;
                 found=1;
              }
              break;
         case AUDIO_U16MSB:
              {
                 format=SND_PCM_SFMT_U16_BE;
                 found=1;
              }
              break;
         case AUDIO_S32LSB:
              {
                 format=SND_PCM_SFMT_S32_LE;
                 found=1;
              }
              break;
         case AUDIO_S32MSB:
              {
                 format=SND_PCM_SFMT_S32_BE;
                 found=1;
              }
              break;
         case AUDIO_F32LSB:
              {
                 format=SND_PCM_SFMT_FLOAT_LE;
                 found=1;
              }
              break;
         case AUDIO_F32MSB:
              {
                 format=SND_PCM_SFMT_FLOAT_BE;
                 found=1;
              }
              break;
         default:
              {
                 break;
              }
      }

      if (!found)
      {
         test_format = SDL_NextAudioFormat();
      }
   }

   /* assumes test_format not 0 on success */
   if (test_format==0)
   {
      QSA_CloseDevice(this);
      SDL_SetError("QSA: Couldn't find any hardware audio formats");
      return 0;
   }

   this->spec.format=test_format;

   /* Set the audio format */
   cparams.format.format=format;

   /* Set mono/stereo/4ch/6ch/8ch audio */
   cparams.format.voices=this->spec.channels;

   /* Set rate */
   cparams.format.rate=this->spec.freq;

   /* Setup the transfer parameters according to cparams */
   status=snd_pcm_plugin_params(this->hidden->audio_handle, &cparams);
   if (status<0)
   {
      QSA_CloseDevice(this);
      QSA_SetError("snd_pcm_channel_params", status);
      return 0;
   }

   /* Make sure channel is setup right one last time */
   SDL_memset(&csetup, '\0', sizeof(csetup));
   if (!this->hidden->iscapture)
   {
      csetup.channel=SND_PCM_CHANNEL_PLAYBACK;
   }
   else
   {
      csetup.channel=SND_PCM_CHANNEL_CAPTURE;
   }

   /* Setup an audio channel */
   if (snd_pcm_plugin_setup(this->hidden->audio_handle, &csetup) < 0)
   {
      QSA_CloseDevice(this);
      SDL_SetError("QSA: Unable to setup channel\n");
      return 0;
   }

   /* Calculate the final parameters for this audio specification */
   SDL_CalculateAudioSpec(&this->spec);

   this->hidden->pcm_len = this->spec.size;

   if (this->hidden->pcm_len==0)
   {
      this->hidden->pcm_len=csetup.buf.block.frag_size * this->spec.channels *
                           (snd_pcm_format_width(format) / 8);
   }

   /*
    * Allocate memory to the audio buffer and initialize with silence
    *  (Note that buffer size must be a multiple of fragment size, so find
    *  closest multiple)
    */
   this->hidden->pcm_buf=(Uint8*)SDL_AllocAudioMem(this->hidden->pcm_len);
   if (this->hidden->pcm_buf==NULL)
   {
      QSA_CloseDevice(this);
      SDL_OutOfMemory();
      return 0;
   }
   SDL_memset(this->hidden->pcm_buf, this->spec.silence, this->hidden->pcm_len);

   /* get the file descriptor */
   if (!this->hidden->iscapture)
   {
      this->hidden->audio_fd=snd_pcm_file_descriptor(this->hidden->audio_handle,
                                                     SND_PCM_CHANNEL_PLAYBACK);
   }
   else
   {
      this->hidden->audio_fd=snd_pcm_file_descriptor(this->hidden->audio_handle,
                                                     SND_PCM_CHANNEL_CAPTURE);
   }

   if (this->hidden->audio_fd<0)
   {
      QSA_CloseDevice(this);
      QSA_SetError("snd_pcm_file_descriptor", status);
      return 0;
   }

   /* Prepare an audio channel */
   if (!this->hidden->iscapture)
   {
      /* Prepare audio playback */
      status=snd_pcm_plugin_prepare(this->hidden->audio_handle, SND_PCM_CHANNEL_PLAYBACK);
   }
   else
   {
      /* Prepare audio capture */
      status=snd_pcm_plugin_prepare(this->hidden->audio_handle, SND_PCM_CHANNEL_CAPTURE);
   }

   if (status<0)
   {
      QSA_CloseDevice(this);
      QSA_SetError("snd_pcm_plugin_prepare", status);
      return 0;
   }

   /* We're really ready to rock and roll. :-) */
   return 1;
}

int QSA_DetectDevices(int iscapture)
{
   uint32_t it;
   uint32_t cards;
   uint32_t devices;
   int32_t  status;

   /* Detect amount of available devices       */
   /* this value can be changed in the runtime */
   cards=snd_cards();

   /* If io-audio manager is not running we will get 0 as number */
   /* of available audio devices                                 */
   if (cards==0)
   {
      /* We have no any available audio devices */
      return 0;
   }

   /* Find requested devices by type */
   if (!iscapture)
   {
      /* Playback devices enumeration requested */
      for(it=0; it<cards; it++)
      {
         devices=0;
         do {
            status=snd_card_get_longname(it, qsa_playback_device[qsa_playback_devices].name, QSA_MAX_NAME_LENGTH);
            if (status==EOK)
            {
               snd_pcm_t* handle;

               /* Add device number to device name */
               sprintf(qsa_playback_device[qsa_playback_devices].name + SDL_strlen(qsa_playback_device[qsa_playback_devices].name), " d%d", devices);

               /* Store associated card number id */
               qsa_playback_device[qsa_playback_devices].cardno=it;

               /* Check if this device id could play anything */
               status=snd_pcm_open(&handle, it, devices, SND_PCM_OPEN_PLAYBACK);
               if (status==EOK)
               {
                  qsa_playback_device[qsa_playback_devices].deviceno=devices;
                  status=snd_pcm_close(handle);
                  if (status==EOK)
                  {
                     qsa_playback_devices++;
                  }
               }
               else
               {
                  /* Check if we got end of devices list */
                  if (status==-ENOENT)
                  {
                     break;
                  }
               }
            }
            else
            {
               break;
            }

            /* Check if we reached maximum devices count */
            if (qsa_playback_devices>=QSA_MAX_DEVICES)
            {
               break;
            }
            devices++;
         } while(1);

         /* Check if we reached maximum devices count */
         if (qsa_playback_devices>=QSA_MAX_DEVICES)
         {
            break;
         }
      }
   }
   else
   {
      /* Capture devices enumeration requested */
      for(it=0; it<cards; it++)
      {
         devices=0;
         do {
            status=snd_card_get_longname(it, qsa_capture_device[qsa_capture_devices].name, QSA_MAX_NAME_LENGTH);
            if (status==EOK)
            {
               snd_pcm_t* handle;

               /* Add device number to device name */
               sprintf(qsa_capture_device[qsa_capture_devices].name + SDL_strlen(qsa_capture_device[qsa_capture_devices].name), " d%d", devices);

               /* Store associated card number id */
               qsa_capture_device[qsa_capture_devices].cardno=it;

               /* Check if this device id could play anything */
               status=snd_pcm_open(&handle, it, devices, SND_PCM_OPEN_CAPTURE);
               if (status==EOK)
               {
                  qsa_capture_device[qsa_capture_devices].deviceno=devices;
                  status=snd_pcm_close(handle);
                  if (status==EOK)
                  {
                     qsa_capture_devices++;
                  }
               }
               else
               {
                  /* Check if we got end of devices list */
                  if (status==-ENOENT)
                  {
                     break;
                  }
               }

               /* Check if we reached maximum devices count */
               if (qsa_capture_devices>=QSA_MAX_DEVICES)
               {
                  break;
               }
            }
            else
            {
               break;
            }
            devices++;
         } while(1);

         /* Check if we reached maximum devices count */
         if (qsa_capture_devices>=QSA_MAX_DEVICES)
         {
            break;
         }
      }
   }

   /* Return amount of available playback or capture devices */
   if (!iscapture)
   {
      return qsa_playback_devices;
   }
   else
   {
      return qsa_capture_devices;
   }
}

const char* QSA_GetDeviceName(int index, int iscapture)
{
   if (!iscapture)
   {
      if (index>=qsa_playback_devices)
      {
         return "No such playback device";
      }

      return qsa_playback_device[index].name;
   }
   else
   {
      if (index>=qsa_capture_devices)
      {
         return "No such capture device";
      }

      return qsa_capture_device[index].name;
   }
}

void QSA_WaitDone(_THIS)
{
   if (!this->hidden->iscapture)
   {
      if (this->hidden->audio_handle!=NULL)
      {
         /* Wait till last fragment is played and stop channel */
         snd_pcm_plugin_flush(this->hidden->audio_handle, SND_PCM_CHANNEL_PLAYBACK);
      }
   }
   else
   {
      if (this->hidden->audio_handle!=NULL)
      {
         /* Discard all unread data and stop channel */
         snd_pcm_plugin_flush(this->hidden->audio_handle, SND_PCM_CHANNEL_CAPTURE);
      }
   }
}

void QSA_Deinitialize(void)
{
   /* Clear devices array on shutdown */
   SDL_memset(qsa_playback_device, 0x00, sizeof(QSA_Device)*QSA_MAX_DEVICES);
   SDL_memset(qsa_capture_device, 0x00, sizeof(QSA_Device)*QSA_MAX_DEVICES);
   qsa_playback_devices=0;
   qsa_capture_devices=0;
}

static int QSA_Init(SDL_AudioDriverImpl* impl)
{
   snd_pcm_t* handle=NULL;
   int32_t    status=0;

   /* Clear devices array */
   SDL_memset(qsa_playback_device, 0x00, sizeof(QSA_Device)*QSA_MAX_DEVICES);
   SDL_memset(qsa_capture_device, 0x00, sizeof(QSA_Device)*QSA_MAX_DEVICES);
   qsa_playback_devices=0;
   qsa_capture_devices=0;

   /* Set function pointers                                     */
   /* DeviceLock and DeviceUnlock functions are used default,   */
   /* provided by SDL, which uses pthread_mutex for lock/unlock */
   impl->DetectDevices=QSA_DetectDevices;
   impl->GetDeviceName=QSA_GetDeviceName;
   impl->OpenDevice=QSA_OpenDevice;
   impl->ThreadInit=QSA_ThreadInit;
   impl->WaitDevice=QSA_WaitDevice;
   impl->PlayDevice=QSA_PlayDevice;
   impl->GetDeviceBuf=QSA_GetDeviceBuf;
   impl->CloseDevice=QSA_CloseDevice;
   impl->WaitDone=QSA_WaitDone;
   impl->Deinitialize=QSA_Deinitialize;
   impl->LockDevice=NULL;
   impl->UnlockDevice=NULL;

   impl->OnlyHasDefaultOutputDevice=0;
   impl->ProvidesOwnCallbackThread=0;
   impl->SkipMixerLock=0;
   impl->HasCaptureSupport=1;
   impl->OnlyHasDefaultOutputDevice=0;
   impl->OnlyHasDefaultInputDevice=0;

   /* Check if io-audio manager is running or not */
   status=snd_cards();
   if (status==0)
   {
      /* if no, return immediately */
      return 1;
   }

   /* At this point we are definitely has an audio device */
   return 2;
}

AudioBootStrap QSAAUDIO_bootstrap=
{
   DRIVER_NAME, "QNX QSA Audio", QSA_Init, 0
};

/* vi: set ts=4 sw=4 expandtab: */