text: #ifndef ALSA9_HELPERS_H
  #define ALSA9_HELPERS_H
  
  #define ALSA_PCM_NEW_HW_PARAMS_API
  #define ALSA_PCM_NEW_SW_PARAMS_API
  #include <alsa/asoundlib.h>
  
  class Alsa9Buf
  {
  private:
  	int channels, samplebits;
  	unsigned samplerate;
  	int buffersize;
  	int64_t last_cursor_pos;
  
  	snd_pcm_uframes_t preferred_writeahead, preferred_chunksize;
  	snd_pcm_uframes_t writeahead, chunksize;
  
  	snd_pcm_t *pcm;
  
  	bool Recover( int r );
  	bool SetHWParams();
  	bool SetSWParams();
  
  	static void ErrorHandler(const char *file, int line, const char *function, int err, const char *fmt, ...);
  		
  public:
  	static void InitializeErrorHandler();
  	static void GetSoundCardDebugInfo();
  	static RString GetHardwareID( RString name="" );
  		
  	Alsa9Buf();
  	RString Init( int channels,
  			int iWriteahead,
  			int iChunkSize,
  			int iSampleRate );
  	~Alsa9Buf();
  	
  	int GetNumFramesToFill();
  	bool WaitUntilFramesCanBeFilled( int timeout_ms );
  	void Write( const int16_t *buffer, int frames );
  	
  	void Play();
  	void Stop();
  	void SetVolume(float vol);
  	int GetSampleRate() const { return samplerate; }
  
  	int64_t GetPosition() const;
  	int64_t GetPlayPos() const { return last_cursor_pos; }
  };
  #endif
  
  /*
   * (c) 2002-2004 Glenn Maynard, Aaron VonderHaar
   * All rights reserved.
   * 
   * 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, and/or sell copies of the Software, and to permit persons to
   * whom the Software is furnished to do so, provided that the above
   * copyright notice(s) and this permission notice appear in all copies of
   * the Software and that both the above copyright notice(s) and this
   * permission notice appear in supporting documentation.
   * 
   * 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 OF
   * THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
   * INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
   * OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
   * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
   * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
   * PERFORMANCE OF THIS SOFTWARE.
   */
  