AudioALSA.hxx

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#ifndef ALSA_PCM_HDR
#define ALSA_PCM_HDR
/*
  Copyright (c) 2012, Matthew H. Reilly (kb1vc)
  All rights reserved.

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are
  met:

  Redistributions of source code must retain the above copyright
  notice, this list of conditions and the following disclaimer.
  Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer in
  the documentation and/or other materials provided with the
  distribution.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include "SoDaBase.hxx"
#include "AudioIfc.hxx"
#include <string>
#if HAVE_LIBASOUND
#  include <alsa/asoundlib.h>
#  define ALSA_DEF
#else
#  define ALSA_DEF { throw SoDa::SoDaException("ALSA Sound Library is not enabled in this build version."); } 
#endif
#include <boost/format.hpp>
#include <iostream>
#include <stdexcept>

namespace SoDa {
  class AudioALSA : public AudioIfc {
  public:
    AudioALSA(unsigned int _sample_rate,
          AudioIfc::DataFormat _fmt,
          unsigned int _sample_count_hint = 1024,
          std::string audio_port_name = std::string("default"));

    ~AudioALSA() {
#if HAVE_LIBASOUND
      snd_pcm_close(pcm_out);
#endif      
    }
    
    int send(void * buf, unsigned int len) ALSA_DEF ;

    bool sendBufferReady(unsigned int len) ALSA_DEF ;

    int recv(void * buf, unsigned int len, bool block = true) ALSA_DEF ; 

    bool recvBufferReady(unsigned int len) ALSA_DEF ;

    void sleepOut() {
#if HAVE_LIBASOUND
      snd_pcm_drain(pcm_out);
#endif
    }
    void wakeOut() {
#if HAVE_LIBASOUND
      int err; 
      if((err = snd_pcm_prepare(pcm_out)) < 0) {
    throw
      SoDaException((boost::format("AudioALSA::wakeOut() Failed to wake after sleepOut() pcm_prepare -- %s")
             % snd_strerror(err)).str(), this);
      }
      if((err = snd_pcm_start(pcm_out)) < 0) {
    throw
      SoDaException((boost::format("AudioALSA::wakeOut() Failed to wake after sleepOut() pcm_start -- %s")
             % snd_strerror(err)).str(), this);
      }
#endif
    }
        
    void sleepIn() {
#if HAVE_LIBASOUND
      snd_pcm_drop(pcm_in);

      // now read the input buffers until they're empty
      int buf[1000];      
      int len = 1000; 
      int stat = 1;
      while(stat > 0) {
    stat = snd_pcm_readi(pcm_in, buf, len);
    if(stat == 0) break; 
    else if(stat == -EAGAIN) continue; 
    else break; 
      }
#endif
    }

    void wakeIn() {
#if HAVE_LIBASOUND
      int err; 
      if((err = snd_pcm_prepare(pcm_in)) < 0) {
    throw
      SoDaException((boost::format("AudioALSA::wakeIn() Failed to wake after sleepIn() -- %s")
             % snd_strerror(err)).str(), this);
      }
      if((err = snd_pcm_start(pcm_in)) < 0) {
    throw
      SoDaException((boost::format("AudioALSA::wakeIn() Failed to wake after sleepIn() -- %s")
             % snd_strerror(err)).str(), this);
      }
#endif
    }
#if HAVE_LIBASOUND
    std::string currentPlaybackState() { 
      std::string cs = currentState(pcm_out);      
      return (boost::format("%s  ready_frames = %d") % cs % snd_pcm_avail(pcm_out)).str();
    }

    std::string currentCaptureState() { 
      return currentState(pcm_in);
    }
#endif
  protected:
#if HAVE_LIBASOUND    
    snd_pcm_t * pcm_out; 
    snd_pcm_t * pcm_in;  
    snd_pcm_hw_params_t * hw_in_params;  
    snd_pcm_hw_params_t * hw_out_params; 

    std::string currentState(snd_pcm_t * dev) {
      snd_pcm_state_t st = snd_pcm_state(dev);

      switch (st) {
      case SND_PCM_STATE_OPEN:
    return std::string("SND_PCM_STATE_OPEN");
    break;
      case SND_PCM_STATE_SETUP:
    return std::string("SND_PCM_STATE_SETUP");
    break;
      case SND_PCM_STATE_PREPARED:
    return std::string("SND_PCM_STATE_PREPARED");
    break;
      case SND_PCM_STATE_RUNNING:
    return std::string("SND_PCM_STATE_RUNNING");
    break;
      case SND_PCM_STATE_XRUN:
    return std::string("SND_PCM_STATE_XRUN");
    break;
      case SND_PCM_STATE_DRAINING:
    return std::string("SND_PCM_STATE_DRAINING");
    break;
      case SND_PCM_STATE_PAUSED:
    return std::string("SND_PCM_STATE_PAUSED");
    break;
      case SND_PCM_STATE_SUSPENDED:
    return std::string("SND_PCM_STATE_SUSPENDED");
    break;
      case SND_PCM_STATE_DISCONNECTED:
    return std::string("SND_PCM_STATE_DISCONNECTED");
    break;
      default:
    return std::string("BADSTATE-UNKNOWN");
      }
    }

    void setupPlayback(std::string audio_port_name);

    void setupCapture(std::string audio_port_name); 

    void setupParams(snd_pcm_t * dev, snd_pcm_hw_params_t * & hw_params);
    
    snd_pcm_format_t translateFormat(AudioIfc::DataFormat fmt);

    void checkStatus(int err, const std::string & exp, bool fatal = false) {
      
      if (err < 0) {
    if(fatal) throw SoDaException((boost::format("%s %s") % exp % snd_strerror(err)).str(), this);
    else std::cerr << boost::format("%s %s %s\n") % getObjName() % exp % snd_strerror(err);
      }
    }
#endif // HAVE_LIBASOUND
  };
}


#endif