ALSA9Helpers.h

#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 std::string GetHardwareID(std::string name = "");
 
    Alsa9Buf();
    std::string 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