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vorbis.cpp

/* ScummVM - Scumm Interpreter
 * Copyright (C) 2003-2004 The ScummVM project
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * $Header: /cvsroot/scummvm/scummvm/sound/vorbis.cpp,v 1.18 2004/11/27 13:54:08 fingolfin Exp $
 *
 */

#include "sound/vorbis.h"

#ifdef USE_VORBIS

#include "common/file.h"
#include "common/util.h"

#include "sound/audiostream.h"
#include "sound/audiocd.h"

#include <vorbis/vorbisfile.h>


static AudioStream *makeVorbisStream(OggVorbis_File *file, int duration);


#pragma mark -
#pragma mark --- Ogg Vorbis Audio CD emulation ---
#pragma mark -

class VorbisTrackInfo : public DigitalTrackInfo {
private:
      File *_file;
      OggVorbis_File _ov_file;
      bool _error_flag;

public:
      VorbisTrackInfo(File *file);
      ~VorbisTrackInfo();
      bool openTrack();
      bool error() { return _error_flag; }
      void play(SoundMixer *mixer, PlayingSoundHandle *handle, int startFrame, int duration);
};


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

struct file_info {
      File *file;
      int start, curr_pos;
      size_t len;
};

static size_t read_wrap(void *ptr, size_t size, size_t nmemb, void *datasource) {
      file_info *f = (file_info *) datasource;
      int result;

      nmemb *= size;
      if (f->curr_pos > (int) f->len)
            nmemb = 0;
      else if (nmemb > f->len - f->curr_pos)
            nmemb = f->len - f->curr_pos;
      // There is no guarantee that the Vorbis stream is alone in accessing
      // the file, so make sure the current position is what we think it is.
      f->file->seek(f->start + f->curr_pos);
      result = f->file->read(ptr, nmemb);
      if (result == -1) {
            f->curr_pos = f->file->pos() - f->start;
            return (size_t) -1;
      } else {
            f->curr_pos += result;
            return result / size;
      }
}

static int seek_wrap(void *datasource, ogg_int64_t offset, int whence) {
      file_info *f = (file_info *) datasource;

      if (whence == SEEK_SET)
            offset += f->start;
      else if (whence == SEEK_END) {
            offset += f->start + f->len;
            whence = SEEK_SET;
      }

      f->file->seek(offset, whence);
      f->curr_pos = f->file->pos() - f->start;
      return f->curr_pos;
}

static int close_wrap(void *datasource) {
      file_info *f = (file_info *) datasource;

      f->file->decRef();
      delete f;
      return 0;
}

static long tell_wrap(void *datasource) {
      file_info *f = (file_info *) datasource;

      return f->curr_pos;
}

static ov_callbacks g_File_wrap = {
      read_wrap, seek_wrap, close_wrap, tell_wrap
};


VorbisTrackInfo::VorbisTrackInfo(File *file) {
      
      _file = file;
      if (openTrack()) {
            warning("Invalid file format");
            _error_flag = true;
            _file = 0;
      } else {
            _error_flag = false;
            _file->incRef();
            ov_clear(&_ov_file);
      }
}

bool VorbisTrackInfo::openTrack() {
      assert(_file);

      file_info *f = new file_info;

      f->file = _file;
      f->start = 0;
      f->len = _file->size();
      f->curr_pos = 0;
      _file->seek(0);
      
      bool err = (ov_open_callbacks((void *) f, &_ov_file, NULL, 0, g_File_wrap) < 0);
      
      if (err) {
            delete f;
      } else {
            _file->incRef();
      }

      return err;
}

VorbisTrackInfo::~VorbisTrackInfo() {
      if (! _error_flag) {
            ov_clear(&_ov_file);
            _file->decRef();
      }
}

#ifdef CHUNKSIZE
#define VORBIS_TREMOR
#endif

void VorbisTrackInfo::play(SoundMixer *mixer, PlayingSoundHandle *handle, int startFrame, int duration) {

      bool err = openTrack();
      assert(!err);

#ifdef VORBIS_TREMOR
      ov_time_seek(&_ov_file, (ogg_int64_t)(startFrame / 75.0 * 1000));
#else
      ov_time_seek(&_ov_file, startFrame / 75.0);
#endif

      AudioStream *input = makeVorbisStream(&_ov_file, duration * ov_info(&_ov_file, -1)->rate / 75);
      mixer->playInputStream(handle, input, true);
}

DigitalTrackInfo *getVorbisTrack(int track) {
      char track_name[32];
      File *file = new File();

      sprintf(track_name, "track%d.ogg", track);
      file->open(track_name);

      if (file->isOpen()) {
            VorbisTrackInfo *trackInfo = new VorbisTrackInfo(file);
            file->decRef();
            if (!trackInfo->error())
                  return trackInfo;
            delete trackInfo;
      }
      delete file;
      return NULL;
}

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


class VorbisInputStream : public AudioStream {
      OggVorbis_File *_ov_file;
      int _end_pos;
      int _numChannels;
      int16 _buffer[4096];
      const int16 *_bufferEnd;
      const int16 *_pos;
      bool _deleteFileAfterUse;
      
      void refill();
      inline bool eosIntern() const;
public:
      VorbisInputStream(OggVorbis_File *file, int duration, bool deleteFileAfterUse);
      ~VorbisInputStream();

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

      bool endOfData() const        { return eosIntern(); }
      bool isStereo() const         { return _numChannels >= 2; }
      
      int getRate() const                 { return ov_info(_ov_file, -1)->rate; }

};


#ifdef CHUNKSIZE
#define VORBIS_TREMOR
#endif


VorbisInputStream::VorbisInputStream(OggVorbis_File *file, int duration, bool deleteFileAfterUse) 
      : _ov_file(file),
      _bufferEnd(_buffer + ARRAYSIZE(_buffer)),
      _deleteFileAfterUse(deleteFileAfterUse) {

      // Check the header, determine if this is a stereo stream
      _numChannels = ov_info(_ov_file, -1)->channels;

      // Determine the end position
      if (duration)
            _end_pos = ov_pcm_tell(_ov_file) + duration;
      else
            _end_pos = ov_pcm_total(_ov_file, -1);

      // Read in initial data
      refill();
}

VorbisInputStream::~VorbisInputStream() {
      ov_clear(_ov_file);
      if (_deleteFileAfterUse)
            delete _ov_file;
}

inline bool VorbisInputStream::eosIntern() const {
      return _pos >= _bufferEnd;
}

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

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

      while (len_left > 0 && _end_pos > ov_pcm_tell(_ov_file)) {
            long result = ov_read(_ov_file, read_pos, len_left,
#ifndef VORBIS_TREMOR
#ifdef SCUMM_BIG_ENDIAN
                                    1,
#else
                                    0,
#endif
                                    2,    // 16 bit
                                    1,    // signed
#endif
                                    NULL);
            if (result == OV_HOLE) {
                  // Possibly recoverable, just warn about it
                  warning("Corrupted data in Vorbis file");
            } else if (result <= 0) {
                  if (result < 0)
                        debug(1, "Decode error %ld in Vorbis file", result);
                  // Don't delete it yet, that causes problems in
                  // the CD player emulation code.
                  memset(read_pos, 0, len_left);
                  break;
            } else {
                  len_left -= result;
                  read_pos += result;
            }
      }

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

static AudioStream *makeVorbisStream(OggVorbis_File *file, int duration) {
      return new VorbisInputStream(file, duration, false);
}

AudioStream *makeVorbisStream(File *file, uint32 size) {
      OggVorbis_File *ov_file = new OggVorbis_File;
      file_info *f = new file_info;

      f->file = file;
      f->start = file->pos();
      f->len = size;
      f->curr_pos = 0;

      if (ov_open_callbacks((void *) f, ov_file, NULL, 0, g_File_wrap) < 0) {
            warning("Invalid file format");
            delete ov_file;
            delete f;
            return 0;
      } else {
            file->incRef();
            return new VorbisInputStream(ov_file, 0, true);
      }
}

#endif

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