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vorbis.cpp

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

// Disable symbol overrides for FILE and fseek as those are used in the
// Vorbis headers.
#define FORBIDDEN_SYMBOL_EXCEPTION_FILE
#define FORBIDDEN_SYMBOL_EXCEPTION_fseek

#include "audio/decoders/vorbis.h"

#ifdef USE_VORBIS

#include "common/stream.h"
#include "common/textconsole.h"
#include "common/util.h"

#include "audio/audiostream.h"

#ifdef USE_TREMOR
#ifdef USE_TREMOLO
#include <tremolo/ivorbisfile.h>
#else
#include <tremor/ivorbisfile.h>
#endif
#else
#include <vorbis/vorbisfile.h>
#endif


namespace Audio {

// These are wrapper functions to allow using a SeekableReadStream object to
// provide data to the OggVorbis_File object.

static size_t read_stream_wrap(void *ptr, size_t size, size_t nmemb, void *datasource) {
      Common::SeekableReadStream *stream = (Common::SeekableReadStream *)datasource;

      uint32 result = stream->read(ptr, size * nmemb);

      return result / size;
}

static int seek_stream_wrap(void *datasource, ogg_int64_t offset, int whence) {
      Common::SeekableReadStream *stream = (Common::SeekableReadStream *)datasource;
      stream->seek((int32)offset, whence);
      return stream->pos();
}

static int close_stream_wrap(void *datasource) {
      // Do nothing -- we leave it up to the VorbisStream to free memory as appropriate.
      return 0;
}

static long tell_stream_wrap(void *datasource) {
      Common::SeekableReadStream *stream = (Common::SeekableReadStream *)datasource;
      return stream->pos();
}

static ov_callbacks g_stream_wrap = {
      read_stream_wrap, seek_stream_wrap, close_stream_wrap, tell_stream_wrap
};



#pragma mark -
#pragma mark --- Ogg Vorbis stream ---
#pragma mark -


class VorbisStream : public SeekableAudioStream {
protected:
      Common::SeekableReadStream *_inStream;
      DisposeAfterUse::Flag _disposeAfterUse;

      bool _isStereo;
      int _rate;

      Timestamp _length;

      OggVorbis_File _ovFile;

      int16 _buffer[4096];
      const int16 *_bufferEnd;
      const int16 *_pos;

public:
      // startTime / duration are in milliseconds
      VorbisStream(Common::SeekableReadStream *inStream, DisposeAfterUse::Flag dispose);
      ~VorbisStream();

      int readBuffer(int16 *buffer, const int numSamples);

      bool endOfData() const        { return _pos >= _bufferEnd; }
      bool isStereo() const         { return _isStereo; }
      int getRate() const                 { return _rate; }

      bool seek(const Timestamp &where);
      Timestamp getLength() const { return _length; }
protected:
      bool refill();
};

VorbisStream::VorbisStream(Common::SeekableReadStream *inStream, DisposeAfterUse::Flag dispose) :
      _inStream(inStream),
      _disposeAfterUse(dispose),
      _length(0, 1000),
      _bufferEnd(_buffer + ARRAYSIZE(_buffer)) {

      int res = ov_open_callbacks(inStream, &_ovFile, NULL, 0, g_stream_wrap);
      if (res < 0) {
            warning("Could not create Vorbis stream (%d)", res);
            _pos = _bufferEnd;
            return;
      }

      // Read in initial data
      if (!refill())
            return;

      // Setup some header information
      _isStereo = ov_info(&_ovFile, -1)->channels >= 2;
      _rate = ov_info(&_ovFile, -1)->rate;

#ifdef USE_TREMOR
      _length = Timestamp(ov_time_total(&_ovFile, -1), getRate());
#else
      _length = Timestamp(uint32(ov_time_total(&_ovFile, -1) * 1000.0), getRate());
#endif
}

VorbisStream::~VorbisStream() {
      ov_clear(&_ovFile);
      if (_disposeAfterUse == DisposeAfterUse::YES)
            delete _inStream;
}

int VorbisStream::readBuffer(int16 *buffer, const int numSamples) {
      int samples = 0;
      while (samples < numSamples && _pos < _bufferEnd) {
            const int len = MIN(numSamples - samples, (int)(_bufferEnd - _pos));
            memcpy(buffer, _pos, len * 2);
            buffer += len;
            _pos += len;
            samples += len;
            if (_pos >= _bufferEnd) {
                  if (!refill())
                        break;
            }
      }
      return samples;
}

bool VorbisStream::seek(const Timestamp &where) {
      // Vorbisfile uses the sample pair number, thus we always use "false" for the isStereo parameter
      // of the convertTimeToStreamPos helper.
      int res = ov_pcm_seek(&_ovFile, convertTimeToStreamPos(where, getRate(), false).totalNumberOfFrames());
      if (res) {
            warning("Error seeking in Vorbis stream (%d)", res);
            _pos = _bufferEnd;
            return false;
      }

      return refill();
}

bool VorbisStream::refill() {
      // Read the samples
      uint len_left = sizeof(_buffer);
      char *read_pos = (char *)_buffer;

      while (len_left > 0) {
            long result;

#ifdef USE_TREMOR
            // Tremor ov_read() always returns data as signed 16 bit interleaved PCM
            // in host byte order. As such, it does not take arguments to request
            // specific signedness, byte order or bit depth as in Vorbisfile.
            result = ov_read(&_ovFile, read_pos, len_left,
                                    NULL);
#else
#ifdef SCUMM_BIG_ENDIAN
            result = ov_read(&_ovFile, read_pos, len_left,
                                    1,
                                    2,    // 16 bit
                                    1,    // signed
                                    NULL);
#else
            result = ov_read(&_ovFile, read_pos, len_left,
                                    0,
                                    2,    // 16 bit
                                    1,    // signed
                                    NULL);
#endif
#endif
            if (result == OV_HOLE) {
                  // Possibly recoverable, just warn about it
                  warning("Corrupted data in Vorbis file");
            } else if (result == 0) {
                  //warning("End of file while reading from Vorbis file");
                  //_pos = _bufferEnd;
                  //return false;
                  break;
            } else if (result < 0) {
                  warning("Error reading from Vorbis stream (%d)", int(result));
                  _pos = _bufferEnd;
                  // Don't delete it yet, that causes problems in
                  // the CD player emulation code.
                  return false;
            } else {
                  len_left -= result;
                  read_pos += result;
            }
      }

      _pos = _buffer;
      _bufferEnd = (int16 *)read_pos;

      return true;
}


#pragma mark -
#pragma mark --- Ogg Vorbis factory functions ---
#pragma mark -

SeekableAudioStream *makeVorbisStream(
      Common::SeekableReadStream *stream,
      DisposeAfterUse::Flag disposeAfterUse) {
      SeekableAudioStream *s = new VorbisStream(stream, disposeAfterUse);
      if (s && s->endOfData()) {
            delete s;
            return 0;
      } else {
            return s;
      }
}

} // End of namespace Audio

#endif // #ifdef USE_VORBIS

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