#include <sys/types.h>#include <stdio.h>#include <fcntl.h>#include <stdlib.h>#include "audio.h"#include <windows.h>static CRITICAL_SECTION        cs;static HWAVEOUT dev    = NULL;static int nBlocks             = 0;static int MAX_BLOCKS  = 6;static _inline void wait(void){   while(nBlocks)       Sleep(77);}static void CALLBACK wave_callback(HWAVE hWave, UINT uMsg, DWORD dwInstance, DWORD dwParam1, DWORD dwParam2){   WAVEHDR *wh;   HGLOBAL hg;   if(uMsg == WOM_DONE)   {       EnterCriticalSection( &cs );       wh = (WAVEHDR *)dwParam1;       waveOutUnprepareHeader(dev, wh, sizeof (WAVEHDR));       //Deallocate the buffer memory       hg = GlobalHandle(wh->lpData);       GlobalUnlock(hg);       GlobalFree(hg);       //Deallocate the header memory       hg = GlobalHandle(wh);       GlobalUnlock(hg);       GlobalFree(hg);       // decrease the number of USED blocks       nBlocks--;       LeaveCriticalSection( &cs );   }}int audio_open(struct audio_info_struct *ai){   MMRESULT res;   WAVEFORMATEX outFormatex;   if(ai->rate == -1)       return(0);   if(!waveOutGetNumDevs())   {       MessageBox(NULL, "No audio devices present!", "Error...", MB_OK);       return -1;   }   outFormatex.wFormatTag      = WAVE_FORMAT_PCM;   outFormatex.wBitsPerSample  = 16;   outFormatex.nChannels       = 2;   outFormatex.nSamplesPerSec  = ai->rate;   outFormatex.nAvgBytesPerSec = outFormatex.nSamplesPerSec * outFormatex.nChannels * outFormatex.wBitsPerSample/8;   outFormatex.nBlockAlign     = outFormatex.nChannels * outFormatex.wBitsPerSample/8;   res = waveOutOpen(&dev, (UINT)ai->device, &outFormatex, (DWORD)wave_callback, 0, CALLBACK_FUNCTION);   if(res != MMSYSERR_NOERROR)   {       switch(res)       {           case MMSYSERR_ALLOCATED:               MessageBox(NULL, "Device Is Already Open", "Error...", MB_OK);               break;           case MMSYSERR_BADDEVICEID:               MessageBox(NULL, "The Specified Device Is out of range", "Error...", MB_OK);               break;           case MMSYSERR_NODRIVER:               MessageBox(NULL, "There is no audio driver in this system.", "Error...", MB_OK);               break;           case MMSYSERR_NOMEM:              MessageBox(NULL, "Unable to allocate sound memory.", "Error...", MB_OK);               break;           case WAVERR_BADFORMAT:               MessageBox(NULL, "This audio format is not supported.", "Error...", MB_OK);               break;           case WAVERR_SYNC:               MessageBox(NULL, "The device is synchronous.", "Error...", MB_OK);               break;           default:               MessageBox(NULL, "Unknown Media Error", "Error...", MB_OK);               break;       }       return -1;   }   waveOutReset(dev);   InitializeCriticalSection(&cs);   return 0;}int audio_reset_parameters(struct audio_info_struct *ai){  return 0;}int audio_rate_best_match(struct audio_info_struct *ai){  return 0;}int audio_set_rate(struct audio_info_struct *ai){  return 0;}int audio_set_channels(struct audio_info_struct *ai){  return 0;}int audio_set_format(struct audio_info_struct *ai){  return 0;}int audio_get_formats(struct audio_info_struct *ai){  return AUDIO_FORMAT_SIGNED_16;}int audio_play_samples(struct audio_info_struct *ai,unsigned char *buf,int len){   HGLOBAL hg, hg2;   LPWAVEHDR wh;   MMRESULT res;   void *b;   ///////////////////////////////////////////////////////   //  Wait for a few FREE blocks...   ///////////////////////////////////////////////////////   while(nBlocks > MAX_BLOCKS)       Sleep(77);   ////////////////////////////////////////////////////////   // FIRST allocate some memory for a copy of the buffer!   ////////////////////////////////////////////////////////   hg2 = GlobalAlloc(GMEM_MOVEABLE, len);   if(!hg2)   {       MessageBox(NULL, "GlobalAlloc failed!", "Error...",  MB_OK);       return(-1);   }   b = GlobalLock(hg2);   //////////////////////////////////////////////////////////   // Here we can call any modification output functions we want....   ///////////////////////////////////////////////////////////   CopyMemory(b, buf, len);   ///////////////////////////////////////////////////////////   // now make a header and WRITE IT!   ///////////////////////////////////////////////////////////   hg = GlobalAlloc (GMEM_MOVEABLE | GMEM_ZEROINIT, sizeof (WAVEHDR));   if(!hg)   {       return -1;   }   wh = GlobalLock(hg);   wh->dwBufferLength = len;   wh->lpData = b;   EnterCriticalSection( &cs );   res = waveOutPrepareHeader(dev, wh, sizeof (WAVEHDR));   if(res)   {       GlobalUnlock(hg);       GlobalFree(hg);       LeaveCriticalSection( &cs );       return -1;   }   res = waveOutWrite(dev, wh, sizeof (WAVEHDR));   if(res)   {       GlobalUnlock(hg);       GlobalFree(hg);       LeaveCriticalSection( &cs );       return (-1);   }   nBlocks++;   LeaveCriticalSection( &cs );   return(len);}int audio_close(struct audio_info_struct *ai){   if(dev)   {       wait();       waveOutReset(dev);      //reset the device       waveOutClose(dev);      //close the device       dev=NULL;   }   DeleteCriticalSection(&cs);   nBlocks = 0;   return(0);}