oss.cxx

mgcp协议源代码。支持多种编码：g711

/*
 * sound.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 Code is Equivalence Pty. Ltd.
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): Loopback feature: Philip Edelbrock <[e-mail]>.
 *
 * $Log: oss.cxx,v $
 * Revision 1.22  2000/07/04 20:34:16  rogerh
 * Only use ioctl SNDCTL_DSP_SETDUPLEX is Linux. It is not defined in FreeBSD
 * In NetBSD and OpenBSD (using liboss), the ioctl returns EINVAL.
 *
 * Revision 1.21  2000/07/02 14:18:27  craigs
 * Fixed various problems with buffer handling
 *
 * Revision 1.20  2000/07/02 05:49:43  craigs
 * Really fixed race condition in OSS open
 *
 * Revision 1.19  2000/07/02 04:55:18  craigs
 * Fixed stupid mistake with fix for OSS race condition
 *
 * Revision 1.18  2000/07/02 04:50:44  craigs
 * Fixed potential race condition in OSS initialise
 *
 * Revision 1.17  2000/05/11 02:05:54  craigs
 * Fixed problem with PLayFile not recognizing wait flag
 *
 * Revision 1.16  2000/05/10 02:10:44  craigs
 * Added implementation for PlayFile command
 *
 * Revision 1.15  2000/05/02 08:30:26  craigs
 * Removed "memory leaks" caused by brain-dead GNU linker
 *
 * Revision 1.14  2000/04/09 18:19:23  rogerh
 * Add my changes for NetBSD support.
 *
 * Revision 1.13  2000/03/08 12:17:09  rogerh
 * Add OpenBSD support
 *
 * Revision 1.12  2000/03/04 13:02:28  robertj
 * Added simple play functions for sound files.
 *
 * Revision 1.11  2000/02/15 23:11:34  robertj
 * Audio support for FreeBSD, thanks Roger Hardiman.
 *
 * Revision 1.10  2000/01/08 06:41:08  craigs
 * Fixed problem whereby failure to open sound device returns TRUE
 *
 * Revision 1.9  1999/08/24 13:40:26  craigs
 * Fixed problem with EINTR causing sound channel reads and write to fail
 * Thanks to [e-mail]!
 *
 * Revision 1.8  1999/08/17 09:42:22  robertj
 * Fixed close of sound channel in loopback mode closing stdin!
 *
 * Revision 1.7  1999/08/17 09:28:47  robertj
 * Added audio loopback psuedo-device (thanks Philip Edelbrock)
 *
 * Revision 1.6  1999/07/19 01:31:49  craigs
 * Major rewrite to assure ioctls are all done in the correct order as OSS seems
 *    to be incredibly sensitive to this.
 *
 * Revision 1.5  1999/07/11 13:42:13  craigs
 * pthreads support for Linux
 *
 * Revision 1.4  1999/06/30 13:49:26  craigs
 * Added code to allow full duplex audio
 *
 * Revision 1.3  1999/05/28 14:14:29  robertj
 * Added function to get default audio device.
 *
 * Revision 1.2  1999/05/22 12:49:05  craigs
 * Finished implementation for Linux OSS interface
 *
 * Revision 1.1  1999/02/25 03:45:00  robertj
 * Sound driver implementation changes for various unix platforms.
 *
 * Revision 1.1  1999/02/22 13:24:47  robertj
 * Added first cut sound implmentation.
 *
 */

#pragma implementation "sound.h"

#include <ptlib.h>

#ifdef P_LINUX
#include <sys/soundcard.h>
#include <sys/time.h>
#endif

#ifdef P_FREEBSD
#include <machine/soundcard.h>
#endif

#if defined(P_OPENBSD) || defined(P_NETBSD)
#include <soundcard.h>
#endif

///////////////////////////////////////////////////////////////////////////////
// declare type for sound handle dictionary

class SoundHandleEntry : public PObject {

  PCLASSINFO(SoundHandleEntry, PObject)

  public:
    SoundHandleEntry();

    int handle;
    int direction;

    unsigned numChannels;
    unsigned sampleRate;
    unsigned bitsPerSample;
    unsigned fragmentValue;
    BOOL isInitialised;
};

PDICTIONARY(SoundHandleDict, PString, SoundHandleEntry);

#define LOOPBACK_BUFFER_SIZE 5000
#define BYTESINBUF ((startptr<endptr)?(endptr-startptr):(LOOPBACK_BUFFER_SIZE+endptr-startptr))

static char buffer[LOOPBACK_BUFFER_SIZE];
static int  startptr, endptr;

PMutex PSoundChannel::dictMutex;

static SoundHandleDict & handleDict()
{
  static SoundHandleDict dict;
  return dict;
}

PSound::PSound(unsigned channels,
               unsigned samplesPerSecond,
               unsigned bitsPerSample,
               PINDEX   bufferSize,
               const BYTE * buffer)
{
  encoding = 0;
  numChannels = channels;
  sampleRate = samplesPerSecond;
  sampleSize = bitsPerSample;
  SetSize(bufferSize);
  if (buffer != NULL)
    memcpy(GetPointer(), buffer, bufferSize);
}


PSound::PSound(const PFilePath & filename)
{
  encoding = 0;
  numChannels = 1;
  sampleRate = 8000;
  sampleSize = 16;
  Load(filename);
}


PSound & PSound::operator=(const PBYTEArray & data)
{
  PBYTEArray::operator=(data);
  return *this;
}


void PSound::SetFormat(unsigned channels,
                       unsigned samplesPerSecond,
                       unsigned bitsPerSample)
{
  encoding = 0;
  numChannels = channels;
  sampleRate = samplesPerSecond;
  sampleSize = bitsPerSample;
  formatInfo.SetSize(0);
}


BOOL PSound::Load(const PFilePath & /*filename*/)
{
  return FALSE;
}


BOOL PSound::Save(const PFilePath & /*filename*/)
{
  return FALSE;
}


BOOL PSound::Play()
{
  PSoundChannel channel(PSoundChannel::GetDefaultDevice(PSoundChannel::Player),
                        PSoundChannel::Player);
  if (!channel.IsOpen())
    return FALSE;

  return channel.PlaySound(*this, TRUE);
}


BOOL PSound::PlayFile(const PFilePath & file, BOOL wait)
{
  PSoundChannel channel(PSoundChannel::GetDefaultDevice(PSoundChannel::Player),
                        PSoundChannel::Player);
  if (!channel.IsOpen())
    return FALSE;

  return channel.PlayFile(file, wait);
}


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

SoundHandleEntry::SoundHandleEntry()
{
  handle    = -1;
  direction = 0;
}

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

PSoundChannel::PSoundChannel()
{
  Construct();
}


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


void PSoundChannel::Construct()
{
  os_handle = -1;
}


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


PStringArray PSoundChannel::GetDeviceNames(Directions /*dir*/)
{
  static const char * const devices[] = {
    "/dev/audio",
    "/dev/dsp",
    "/dev/dspW",
    "loopback"
  };

  return PStringArray(PARRAYSIZE(devices), devices);
}


PString PSoundChannel::GetDefaultDevice(Directions /*dir*/)
{
  return "/dev/dsp";
}


BOOL PSoundChannel::Open(const PString & _device,
                              Directions _dir,
                                unsigned _numChannels,
                                unsigned _sampleRate,
                                unsigned _bitsPerSample)
{
  Close();

  // lock the dictionary
  PWaitAndSignal mutex(dictMutex);

  // make the direction value 1 or 2
  int dir = _dir + 1;

  // if this device in in the dictionary
  if (handleDict().Contains(_device)) {

    PTRACE(6, "OSS\tOpen occured for existing entry");

    SoundHandleEntry & entry = handleDict()[_device];

    // see if the sound channel is already open in this direction
    if ((entry.direction & dir) != 0) 
      return FALSE;

    // flag this entry as open in this direction
    entry.direction |= dir;
    os_handle = entry.handle;

  } else {

    PTRACE(6, "OSS\tOpen occured for new entry");

    // this is the first time this device has been used
    // open the device in read/write mode always
    if (_device == "loopback") {
      startptr = endptr = 0;
      os_handle = 0; // Use os_handle value 0 to indicate loopback, cannot ever be stdin!
    }
    else if (!ConvertOSError(os_handle = ::open((const char *)_device, O_RDWR))) 
      return FALSE;

    // add the device to the dictionary
    SoundHandleEntry * entry = PNEW SoundHandleEntry;
    handleDict().SetAt(_device, entry); 

    // save the information into the dictionary entry
    entry->handle        = os_handle;
    entry->direction     = dir;
    entry->numChannels   = _numChannels;
    entry->sampleRate    = _sampleRate;
    entry->bitsPerSample = _bitsPerSample;
    entry->isInitialised = FALSE;
    entry->fragmentValue = 0x7fff0008;
  }
   
  // save the direction and device
  direction     = _dir;
  device        = _device;
  isInitialised = FALSE;

  return TRUE;
}

BOOL PSoundChannel::Setup()
{
  PWaitAndSignal mutex(dictMutex);

  if (os_handle < 0) {
    PTRACE(6, "OSS\tSkipping setup of " << device << " as not open");
    return FALSE;
  }

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

  // the device must always be in the dictionary
  PAssertOS(handleDict().Contains(device));

  // get record for the device
  SoundHandleEntry & entry = handleDict()[device];

  // set default return status
  BOOL stat = TRUE;

  // do not re-initialise initialised devices
  if (entry.isInitialised || (device == "loopback")) {
    PTRACE(6, "OSS\tSkipping setup for " << device << " as already initialised");

  } else {
    PTRACE(6, "OSS\tInitialising " << device << "(" << (void *)(&entry) << ")");


#if defined(P_LINUX)
    // enable full duplex (maybe).
    ::ioctl(os_handle, SNDCTL_DSP_SETDUPLEX, 0);
#endif

    stat = FALSE;

  // must always set paramaters in the following order:
  //   buffer paramaters
  //   sample format (number of bits)
  //   number of channels (mon/stereo)
  //   speed (sampling rate)

    int arg, val;

    // reset the device first so it will accept the new parms
    if (ConvertOSError(::ioctl(os_handle, SNDCTL_DSP_RESET, &arg))) {

      // set the write fragment size (applies to sound output only)
      arg = val = entry.fragmentValue;
      ::ioctl(os_handle, SNDCTL_DSP_SETFRAGMENT, &arg); 

      audio_buf_info info;
      ::ioctl(os_handle, SNDCTL_DSP_GETOSPACE, &info);
      PTRACE(6, "OSS\tOutput: fragments = " << info.fragments
                     << ", total frags = " << info.fragstotal
                     << ", frag size   = " << info.fragsize
                     << ", bytes       = " << info.bytes);

      ::ioctl(os_handle, SNDCTL_DSP_GETISPACE, &info);
      PTRACE(6, "OSS\tInput: fragments = " << info.fragments
                     << ", total frags = " << info.fragstotal
                     << ", frag size   = " << info.fragsize
                     << ", bytes       = " << info.bytes);

      arg = val = (entry.bitsPerSample == 16) ? AFMT_S16_LE : AFMT_S8;
      if (ConvertOSError(::ioctl(os_handle, SNDCTL_DSP_SETFMT, &arg)) || (arg != val)) {