sound_alsa.cxx

安装 H323需要的pwlib库

/*
 * sound_alsa.cxx
 *
 * Sound driver implementation.
 *
 * Portable Windows Library
 *
 * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original ALSA Code is 
 * Damien Sandras <[e-mail]>
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): /
 *
 * $Log: sound_alsa.cxx,v $
 * Revision 1.24  2004/11/07 20:23:00  dsandras
 * Removed erroneous update of lastReadCount in previous commit.
 *
 * Revision 1.23  2004/11/07 20:01:32  dsandras
 * Make sure lastWriteCount is updated.
 *
 * Revision 1.22  2004/11/06 16:31:12  dsandras
 * Removed dictionnary copy.
 *
 * Revision 1.21  2004/10/18 11:43:39  dsandras
 * Use Capture instead of Mic when changing the volume. Use the correct mixer when using the Default device.
 *
 * Revision 1.20  2004/10/14 19:30:16  dsandras
 * Removed DMIX and DSNOOP plugins and added support for DEFAULT as it is the correcti way to do things.
 *
 * Revision 1.19  2004/08/30 21:09:41  dsandras
 * Added DSNOOP plugin support.
 *
 * Revision 1.18  2004/05/14 10:15:26  dominance
 * Fixes direct opening of sound output devices. The list of devices does no longer return NULL in that case. Patch provided by Julien Puydt <[e-mail]>.
 *
 * Revision 1.17  2004/04/03 10:33:45  dsandras
 * Use PStringToOrdinal to store the detected devices, that fixes problems if there is a discontinuity in the succession of soundcard ID's. For example the user has card ID 1 and 3, but not 2.
 *
 * Revision 1.16  2004/03/13 12:36:14  dsandras
 * Added support for DMIX plugin output.
 *
 * Revision 1.15  2004/03/04 13:36:13  dsandras
 * Added check so that ALSA doesn't assert on broken installations.
 *
 * Revision 1.14  2004/02/12 09:07:57  csoutheren
 * Fixed typo in ALSA driver, thanks to Julien Puydt
 *
 * Revision 1.13  2004/01/04 20:59:30  dsandras
 * Use set_rate_near instead of set_rate.
 *
 * Revision 1.12  2003/12/28 15:10:35  dsandras
 * Updated to the new PCM API.
 *
 * Revision 1.11  2003/12/18 11:16:41  dominance
 * Removed the ALSA Abort completely upon Damien's request ;)
 *
 * Revision 1.10  2003/12/18 10:38:55  dominance
 * Removed ALSA Abort as it segfaults in various circumstances.
 * Fix proposed by Damien Sandras <[e-mail]>.
 *
 * Revision 1.9  2003/12/09 22:47:10  dsandras
 * Use less aggressive Abort.
 *
 * Revision 1.8  2003/12/03 21:48:21  dsandras
 * Better handling of buffer sizes. Removed unuseful code.
 *
 * Revision 1.7  2003/11/25 20:13:48  dsandras
 * Added #pragma.
 *
 * Revision 1.6  2003/11/25 09:58:01  dsandras
 * Removed Abort call from PlaySound ().
 *
 * Revision 1.5  2003/11/25 09:52:07  dsandras
 * Modified WaitForPlayCompletion so that it uses snd_pcm_drain instead of active waiting.
 *
 * Revision 1.4  2003/11/23 22:09:57  dsandras
 * Removed unuseful stuff and added implementation for functions permitting to play a file or a PSound.
 *
 * Revision 1.3  2003/11/14 05:28:47  csoutheren
 * Updated for new plugin code thanks to Damien and Snark
 *
 */

#pragma implementation "sound_alsa.h"

#include "sound_alsa.h"


PCREATE_SOUND_PLUGIN(ALSA, PSoundChannelALSA)


static PStringToOrdinal playback_devices;
static PStringToOrdinal capture_devices;

///////////////////////////////////////////////////////////////////////////////

PSoundChannelALSA::PSoundChannelALSA()
{
  PSoundChannelALSA::Construct();
}


PSoundChannelALSA::PSoundChannelALSA (const PString &device,
				      Directions dir,
				      unsigned numChannels,
				      unsigned sampleRate,
				      unsigned bitsPerSample)
{
  Construct();
  Open (device, dir, numChannels, sampleRate, bitsPerSample);
}


void PSoundChannelALSA::Construct()
{
  frame_bytes = 0;
  period_size = 0;
  periods = 0;
  card_nr = 0;
  os_handle = NULL;
}


PSoundChannelALSA::~PSoundChannelALSA()
{
  Close();
}


void PSoundChannelALSA::UpdateDictionary (Directions dir)
{
  int card = -1, dev = -1;
  
  snd_ctl_t *handle = NULL;
  snd_ctl_card_info_t *info = NULL;
  snd_pcm_info_t *pcminfo = NULL;
  snd_pcm_stream_t stream;

  char *name = NULL;
  char card_id [32];

  if (dir == Recorder) {

    stream = SND_PCM_STREAM_CAPTURE;
    capture_devices = PStringToOrdinal ();
  }
  else {

    stream = SND_PCM_STREAM_PLAYBACK;
    playback_devices = PStringToOrdinal ();
  }

  snd_ctl_card_info_alloca (&info);
  snd_pcm_info_alloca (&pcminfo);

  /* No sound card found */
  if (snd_card_next (&card) < 0 || card < 0) {

    return;
  }

  while (card >= 0) {

    snprintf (card_id, 32, "hw:%d", card);
    
    if (snd_ctl_open (&handle, card_id, 0) == 0) {

      snd_ctl_card_info (handle, info);

      while (1) {

        snd_ctl_pcm_next_device (handle, &dev);

        if (dev < 0)
          break;

        snd_pcm_info_set_device (pcminfo, dev);
        snd_pcm_info_set_subdevice (pcminfo, 0);
        snd_pcm_info_set_stream (pcminfo, stream);

        if (snd_ctl_pcm_info (handle, pcminfo) >= 0) {

	  snd_card_get_name (card, &name);
	  if (dir == Recorder) 
	    capture_devices.SetAt (name, card);

	  else 
	    playback_devices.SetAt (name, card);
          free (name);
        }
      }
    }

    snd_ctl_close(handle);
    snd_card_next (&card);
  }
}


PStringArray PSoundChannelALSA::GetDeviceNames (Directions dir)
{
  PStringArray devices;
 
  UpdateDictionary (dir);
  
  if (dir == Recorder) {
    
    for (PINDEX j = 0 ; j < capture_devices.GetSize () ; j++) 
      devices += capture_devices.GetKeyAt (j);
  }
  else {

    for (PINDEX j = 0 ; j < playback_devices.GetSize () ; j++) 
      devices += playback_devices.GetKeyAt (j);
  }


  if (devices.GetSize () > 0)
    devices += "Default";
  
  return devices;
}


PString PSoundChannelALSA::GetDefaultDevice(Directions dir)
{
  PStringArray devicenames;
  devicenames = PSoundChannelALSA::GetDeviceNames (dir);

  return devicenames[0];
}


BOOL PSoundChannelALSA::Open (const PString & _device,
                              Directions _dir,
			      unsigned _numChannels,
			      unsigned _sampleRate,
			      unsigned _bitsPerSample)
{
  PString real_device_name;
  POrdinalKey *i = NULL;
  snd_pcm_stream_t stream;

  Close();

  os_handle = NULL;

  if (_dir == Recorder)
    stream = SND_PCM_STREAM_CAPTURE;
  else
    stream = SND_PCM_STREAM_PLAYBACK;

  /* Open in NONBLOCK mode */
  if (_device == "Default") {

    real_device_name = "default";
    card_nr = -2;
  }
  else {

  if ((_dir == Recorder && capture_devices.IsEmpty ())
      || (_dir == Player && playback_devices.IsEmpty ()))
    UpdateDictionary (_dir);

    i = (_dir == Recorder) ? capture_devices.GetAt (_device) : playback_devices.GetAt (_device);

    if (i) {

      real_device_name = "plughw:" + PString (*i);
      card_nr = *i;
    }
    else {

      PTRACE (1, "ALSA\tDevice not found");
      return FALSE;
    }
  }
    
  if (snd_pcm_open (&os_handle, real_device_name, stream, SND_PCM_NONBLOCK) < 0) {

    PTRACE (1, "ALSA\tOpen Failed");
    return FALSE;
  }
  else 
    snd_pcm_nonblock (os_handle, 0);
   
  /* save internal parameters */
  direction = _dir;
  device = real_device_name;
  mNumChannels = _numChannels;
  mSampleRate = _sampleRate;
  mBitsPerSample = _bitsPerSample;
  isInitialised = FALSE;

  PTRACE (1, "ALSA\tDevice " << real_device_name << " Opened");

  return TRUE;
}


BOOL PSoundChannelALSA::Setup()
{
  snd_pcm_hw_params_t *hw_params = NULL;
  snd_pcm_uframes_t buffer_size = 0;
  
  int err = 0;
  enum _snd_pcm_format val = SND_PCM_FORMAT_UNKNOWN;
  BOOL no_error = TRUE;


  if (os_handle == NULL) {

    PTRACE(6, "ALSA\tSkipping setup of " << device << " as not open");
    return FALSE;
  }

  if (isInitialised) {

    PTRACE(6, "ALSA\tSkipping setup of " << device << " as instance already initialised");
    return TRUE;
  }


#if PBYTE_ORDER == PLITTLE_ENDIAN
  val = (mBitsPerSample == 16) ? SND_PCM_FORMAT_S16_LE : SND_PCM_FORMAT_U8;
#else
  val = (mBitsPerSample == 16) ? SND_PCM_FORMAT_S16_BE : SND_PCM_FORMAT_U8;
#endif

  frame_bytes = (mNumChannels * (snd_pcm_format_width (val) / 8));

  snd_pcm_hw_params_alloca (&hw_params);

  if ((err = snd_pcm_hw_params_any (os_handle, hw_params)) < 0) {

    PTRACE (1, "ALSA\tCannot initialize hardware parameter structure " <<
	    snd_strerror (err));
    no_error = FALSE;
  }


  if ((err = snd_pcm_hw_params_set_access (os_handle, hw_params, 
					   SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {

    PTRACE (1, "ALSA\tCannot set access type " <<
	    snd_strerror (err));
    no_error = FALSE;
  }


  if ((err = snd_pcm_hw_params_set_format (os_handle, hw_params, val)) < 0) {

    PTRACE (1, "ALSA\tCannot set sample format " <<
             snd_strerror (err));
    no_error = FALSE;
  }


  if ((err = snd_pcm_hw_params_set_rate_near (os_handle,
					      hw_params, 
					      &mSampleRate,
					      NULL)) < 0) {

    PTRACE (1, "ALSA\tCannot set sample rate " <<
	    snd_strerror (err));
    no_error = FALSE;
  }


  if ((err = snd_pcm_hw_params_set_channels (os_handle, hw_params, 
					     mNumChannels)) < 0) {

    PTRACE (1, "ALSA\tCannot set channel count " <<
             snd_strerror (err));
    no_error = FALSE;
  }


  // Ignore errors here 
  if (periods && period_size) {

    if ((err = snd_pcm_hw_params_set_period_size_near (os_handle, 
						       hw_params, 
						       &period_size, 
						       0)) < 0)
      PTRACE (1, "ALSA\tCannot set period size " <<
	      snd_strerror (err));
    
    if ((err = snd_pcm_hw_params_set_periods_near (os_handle, 
						   hw_params, 
						   &periods,
						   0)) < 0)
      PTRACE (1, "ALSA\tCannot set number of periods " <<
	      snd_strerror (err));

    buffer_size = periods*period_size/frame_bytes;
      
    if ((err = (int) snd_pcm_hw_params_set_buffer_size_near (os_handle, 
							     hw_params, 
							     &buffer_size))
	< 0)
      PTRACE (1, "ALSA\tCannot set buffer size " <<
	      snd_strerror (err));
  }
    
  
  if ((err = snd_pcm_hw_params (os_handle, hw_params)) < 0) {

    PTRACE (1, "ALSA\tCannot set parameters " <<
	    snd_strerror (err));
    no_error = FALSE;
  }

  
  isInitialised = TRUE;

  return no_error;
}


BOOL PSoundChannelALSA::Close()
{
  PWaitAndSignal m(device_mutex);

  /* if the channel isn't open, do nothing */
  if (!os_handle)
    return FALSE;