dvd_udf.c

君正早期ucos系统(只有早期的才不没有打包成库),MPLAYER,文件系统,图片解码,浏览,电子书,录音,想学ucos,识货的人就下吧 russblock fmradio explore set

  while( p < 176 + L_EA + L_AD ) {
    switch( flags & 0x0007 ) {
    case 0: UDFShortAD( &data[ p ], ad, partition ); p += 8;  break;
    case 1: UDFLongAD( &data[ p ], ad );  p += 16; break;
    case 2: UDFExtAD( &data[ p ], ad );   p += 20; break;
    case 3:
      switch( L_AD ) {
      case 8:  UDFShortAD( &data[ p ], ad, partition ); break;
      case 16: UDFLongAD( &data[ p ], ad );  break;
      case 20: UDFExtAD( &data[ p ], ad );   break;
      }
      p += L_AD;
      break;
    default:
      p += L_AD; break;
    }
  }
  return 0;
}

static int UDFFileIdentifier( uint8_t *data, uint8_t *FileCharacteristics,
                              char *FileName, struct AD *FileICB )
{
  uint8_t L_FI;
  uint16_t L_IU;

  *FileCharacteristics = GETN1(18);
  L_FI = GETN1(19);
  UDFLongAD(&data[20], FileICB);
  L_IU = GETN2(36);
  if (L_FI) Unicodedecode(&data[38 + L_IU], L_FI, FileName);
  else FileName[0] = '\0';
  return 4 * ((38 + L_FI + L_IU + 3) / 4);
}

/**
 * Maps ICB to FileAD
 * ICB: Location of ICB of directory to scan
 * FileType: Type of the file
 * File: Location of file the ICB is pointing to
 * return 1 on success, 0 on error;
 */
static int UDFMapICB( dvd_reader_t *device, struct AD ICB, uint8_t *FileType,
                      struct Partition *partition, struct AD *File ) 
{
  uint8_t *LogBlock;
  uint32_t lbnum;
  uint16_t TagID;
  struct icbmap tmpmap;

  lbnum = partition->Start + ICB.Location;
  tmpmap.lbn = lbnum;
  if(GetUDFCache(device, MapCache, lbnum, &tmpmap)) {
    *FileType = tmpmap.filetype;
    *File = tmpmap.file;
    return 1;
  }

  LogBlock = dvdalign_lbmalloc(device, 1);
  if(!LogBlock) {
    return 0;
  }
    
  do {
    if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
      TagID = 0;
    } else {
      UDFDescriptor( LogBlock, &TagID );
    }

    if( TagID == 261 ) {
      UDFFileEntry( LogBlock, FileType, partition, File );
      tmpmap.file = *File;
      tmpmap.filetype = *FileType;
      SetUDFCache(device, MapCache, tmpmap.lbn, &tmpmap);
      dvdalign_lbfree(device, LogBlock);
      return 1;
    };
  } while( ( lbnum <= partition->Start + ICB.Location + ( ICB.Length - 1 )
             / DVD_VIDEO_LB_LEN ) && ( TagID != 261 ) );

  dvdalign_lbfree(device, LogBlock);
  return 0;
}

/**
 * Dir: Location of directory to scan
 * FileName: Name of file to look for
 * FileICB: Location of ICB of the found file
 * return 1 on success, 0 on error;
 */
static int UDFScanDir( dvd_reader_t *device, struct AD Dir, char *FileName,
                       struct Partition *partition, struct AD *FileICB,
                       int cache_file_info) 
{
  char filename[ MAX_UDF_FILE_NAME_LEN ];
  uint8_t *directory;
  uint32_t lbnum;
  uint16_t TagID;
  uint8_t filechar;
  unsigned int p;
  uint8_t *cached_dir = NULL;
  uint32_t dir_lba;
  struct AD tmpICB;
  int found = 0;
  int in_cache = 0;

  /* Scan dir for ICB of file */
  lbnum = partition->Start + Dir.Location;
    
  if(DVDUDFCacheLevel(device, -1) > 0) {
    /* caching */
      
    if(!GetUDFCache(device, LBUDFCache, lbnum, &cached_dir)) {
      dir_lba = (Dir.Length + DVD_VIDEO_LB_LEN) / DVD_VIDEO_LB_LEN;
      if((cached_dir = dvdalign_lbmalloc(device, dir_lba)) == NULL) {
        return 0;
      }
      if( DVDReadLBUDF( device, lbnum, dir_lba, cached_dir, 0) <= 0 ) {
        dvdalign_lbfree(device, cached_dir);
        cached_dir = NULL;
      }
      SetUDFCache(device, LBUDFCache, lbnum, &cached_dir);
    } else {
      in_cache = 1;
    }
      
    if(cached_dir == NULL) {
      return 0;
    }
      
    p = 0;
      
    while( p < Dir.Length ) {
      UDFDescriptor( &cached_dir[ p ], &TagID );
      if( TagID == 257 ) {
        p += UDFFileIdentifier( &cached_dir[ p ], &filechar,
                                filename, &tmpICB );
        if(cache_file_info && !in_cache) {
          uint8_t tmpFiletype;
          struct AD tmpFile;
            
          if( !strcasecmp( FileName, filename ) ) {
            *FileICB = tmpICB;
            found = 1;
              
          }
          UDFMapICB(device, tmpICB, &tmpFiletype,
                    partition, &tmpFile);
        } else {
          if( !strcasecmp( FileName, filename ) ) {
            *FileICB = tmpICB;
            return 1;
          }
        }
      } else {
        if(cache_file_info && (!in_cache) && found) {
          return 1;
        }
        return 0;
      }
    }
    if(cache_file_info && (!in_cache) && found) {
      return 1;
    }
    return 0;
  }

  directory = dvdalign_lbmalloc(device, 2);
  if(!directory) {
    return 0;
  }
  if( DVDReadLBUDF( device, lbnum, 2, directory, 0 ) <= 0 ) {
    dvdalign_lbfree(device, directory);
    return 0;
  }

  p = 0;
  while( p < Dir.Length ) {
    if( p > DVD_VIDEO_LB_LEN ) {
      ++lbnum;
      p -= DVD_VIDEO_LB_LEN;
      Dir.Length -= DVD_VIDEO_LB_LEN;
      if( DVDReadLBUDF( device, lbnum, 2, directory, 0 ) <= 0 ) {
        dvdalign_lbfree(device, directory);
        return 0;
      }
    }
    UDFDescriptor( &directory[ p ], &TagID );
    if( TagID == 257 ) {
      p += UDFFileIdentifier( &directory[ p ], &filechar,
                              filename, FileICB );
      if( !strcasecmp( FileName, filename ) ) {
        dvdalign_lbfree(device, directory);
        return 1;
      }
    } else {
      dvdalign_lbfree(device, directory);
      return 0;
    }
  }

  dvdalign_lbfree(device, directory);
  return 0;
}


static int UDFGetAVDP( dvd_reader_t *device,
                       struct avdp_t *avdp)
{
  uint8_t *Anchor;
  uint32_t lbnum, MVDS_location, MVDS_length;
  uint16_t TagID;
  uint32_t lastsector;
  int terminate;
  struct avdp_t; 
  
  if(GetUDFCache(device, AVDPCache, 0, avdp)) {
    return 1;
  }
  
  /* Find Anchor */
  lastsector = 0;
  lbnum = 256;   /* Try #1, prime anchor */
  terminate = 0;
  
  Anchor = dvdalign_lbmalloc(device, 1);
  if(!Anchor) {
    return 0;
  }
  for(;;) {
    if( DVDReadLBUDF( device, lbnum, 1, Anchor, 0 ) > 0 ) {
      UDFDescriptor( Anchor, &TagID );
    } else {
      TagID = 0;
    }
    if (TagID != 2) {
      /* Not an anchor */
      if( terminate ) {
        dvdalign_lbfree(device, Anchor);
        errno = EMEDIUMTYPE;
        return 0; /* Final try failed */
      } 
      
      if( lastsector ) {
        /* We already found the last sector.  Try #3, alternative
         * backup anchor.  If that fails, don't try again.
         */
        lbnum = lastsector;
        terminate = 1;
      } else {
        /* TODO: Find last sector of the disc (this is optional). */
        if( lastsector ) {
          /* Try #2, backup anchor */
          lbnum = lastsector - 256;
        } else {
          /* Unable to find last sector */
          dvdalign_lbfree(device, Anchor);
          errno = EMEDIUMTYPE;
          return 0;
        }
      }
    } else {
      /* It's an anchor! We can leave */
      break;
    }
  }
  /* Main volume descriptor */
  UDFExtentAD( &Anchor[ 16 ], &MVDS_length, &MVDS_location );
  avdp->mvds.location = MVDS_location;
  avdp->mvds.length = MVDS_length;
  
  /* Backup volume descriptor */
  UDFExtentAD( &Anchor[ 24 ], &MVDS_length, &MVDS_location );
  avdp->rvds.location = MVDS_location;
  avdp->rvds.length = MVDS_length;
  
  SetUDFCache(device, AVDPCache, 0, avdp);
  
  dvdalign_lbfree(device, Anchor);
  return 1;
}

/**
 * Looks for partition on the disc.  Returns 1 if partition found, 0 on error.
 *   partnum: Number of the partition, starting at 0.
 *   part: structure to fill with the partition information
 */
static int UDFFindPartition( dvd_reader_t *device, int partnum,
                             struct Partition *part ) 
{
  uint8_t *LogBlock;
  uint32_t lbnum, MVDS_location, MVDS_length;
  uint16_t TagID;
  int i, volvalid;
  struct avdp_t avdp;

    
  if(!UDFGetAVDP(device, &avdp)) {
    return 0;
  }

  LogBlock = dvdalign_lbmalloc(device, 1);
  if(!LogBlock) {
    return 0;
  }
  /* Main volume descriptor */
  MVDS_location = avdp.mvds.location;
  MVDS_length = avdp.mvds.length;

  part->valid = 0;
  volvalid = 0;
  part->VolumeDesc[ 0 ] = '\0';
  i = 1;
  do {
    /* Find Volume Descriptor */
    lbnum = MVDS_location;
    do {

      if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
        TagID = 0;
      } else {
        UDFDescriptor( LogBlock, &TagID );
      }

      if( ( TagID == 5 ) && ( !part->valid ) ) {
        /* Partition Descriptor */
        UDFPartition( LogBlock, &part->Flags, &part->Number,
                      part->Contents, &part->Start, &part->Length );
        part->valid = ( partnum == part->Number );
      } else if( ( TagID == 6 ) && ( !volvalid ) ) {
        /* Logical Volume Descriptor */
        if( UDFLogVolume( LogBlock, part->VolumeDesc ) ) {  
          /* TODO: sector size wrong! */
        } else {
          volvalid = 1;
        }
      }

    } while( ( lbnum <= MVDS_location + ( MVDS_length - 1 )
               / DVD_VIDEO_LB_LEN ) && ( TagID != 8 )
             && ( ( !part->valid ) || ( !volvalid ) ) );

    if( ( !part->valid) || ( !volvalid ) ) {
      /* Backup volume descriptor */
      MVDS_location = avdp.mvds.location;
      MVDS_length = avdp.mvds.length;
    }
  } while( i-- && ( ( !part->valid ) || ( !volvalid ) ) );

  dvdalign_lbfree(device, LogBlock);
  /* We only care for the partition, not the volume */
  return part->valid;
}

uint32_t UDFFindFile( dvd_reader_t *device, char *filename,
                      uint32_t *filesize )
{
  uint8_t *LogBlock;
  uint32_t lbnum;
  uint16_t TagID;
  struct Partition partition;
  struct AD RootICB, File, ICB;
  char tokenline[ MAX_UDF_FILE_NAME_LEN ];
  char *token;
  uint8_t filetype;
  
  if(filesize) {
    *filesize = 0;
  }
  tokenline[0] = '\0';
  strcat( tokenline, filename );

    
  if(!(GetUDFCache(device, PartitionCache, 0, &partition) &&
       GetUDFCache(device, RootICBCache, 0, &RootICB))) {
    /* Find partition, 0 is the standard location for DVD Video.*/
    if( !UDFFindPartition( device, 0, &partition ) ) {
      return 0;
    }
    SetUDFCache(device, PartitionCache, 0, &partition);
    
    LogBlock = dvdalign_lbmalloc(device, 1);
    if(!LogBlock) {
      return 0;
    }
    /* Find root dir ICB */
    lbnum = partition.Start;
    do {
      if( DVDReadLBUDF( device, lbnum++, 1, LogBlock, 0 ) <= 0 ) {
        TagID = 0;
      } else {
        UDFDescriptor( LogBlock, &TagID );
      }

      /* File Set Descriptor */
      if( TagID == 256 ) {  // File Set Descriptor
        UDFLongAD( &LogBlock[ 400 ], &RootICB );
      }
    } while( ( lbnum < partition.Start + partition.Length )
             && ( TagID != 8 ) && ( TagID != 256 ) );

    dvdalign_lbfree(device, LogBlock);
      
    /* Sanity checks. */
    if( TagID != 256 ) {
      return 0;
    }
    if( RootICB.Partition != 0 ) {
      return 0;
    }
    SetUDFCache(device, RootICBCache, 0, &RootICB);
  }

  /* Find root dir */
  if( !UDFMapICB( device, RootICB, &filetype, &partition, &File ) ) {
    return 0;
  }
  if( filetype != 4 ) {
    return 0;  /* Root dir should be dir */
  }
  {
    int cache_file_info = 0;
    /* Tokenize filepath */
    token = strtok(tokenline, "/");
    
    while( token != NULL ) {
      
      if( !UDFScanDir( device, File, token, &partition, &ICB,
                       cache_file_info)) {
        return 0;
      }
      if( !UDFMapICB( device, ICB, &filetype, &partition, &File ) ) {
        return 0;
      }
      if(!strcmp(token, "VIDEO_TS")) {
        cache_file_info = 1;
      }
      token = strtok( NULL, "/" );
    }
  } 

  /* Sanity check. */
  if( File.Partition != 0 ) {
    return 0;
  }

  if(filesize) {
    *filesize = File.Length;
  }
  /* Hack to not return partition.Start for empty files. */
  if( !File.Location ) {
    return 0;
  } else {
    return partition.Start + File.Location;
  }
}



/**
 * Gets a Descriptor .
 * Returns 1 if descriptor found, 0 on error.
 * id, tagid of descriptor
 * bufsize, size of BlockBuf (must be >= DVD_VIDEO_LB_LEN)
 * and aligned for raw/O_DIRECT read.
 */
static int UDFGetDescriptor( dvd_reader_t *device, int id,
                             uint8_t *descriptor, int bufsize) 
{
  uint32_t lbnum, MVDS_location, MVDS_length;
  struct avdp_t avdp;
  uint16_t TagID;
  uint32_t lastsector;
  int i, terminate;
  int desc_found = 0;
  /* Find Anchor */
  lastsector = 0;
  lbnum = 256;   /* Try #1, prime anchor */
  terminate = 0;
  if(bufsize < DVD_VIDEO_LB_LEN) {
    return 0;
  }
  
  if(!UDFGetAVDP(device, &avdp)) {
    return 0;
  }

  /* Main volume descriptor */
  MVDS_location = avdp.mvds.location;
  MVDS_length = avdp.mvds.length;
  
  i = 1;
  do {
    /* Find  Descriptor */
    lbnum = MVDS_location;
    do {
      
      if( DVDReadLBUDF( device, lbnum++, 1, descriptor, 0 ) <= 0 ) {
        TagID = 0;
      } else {
        UDFDescriptor( descriptor, &TagID );
      }
      
      if( (TagID == id) && ( !desc_found ) ) {
        /* Descriptor */
        desc_found = 1;
      }
    } while( ( lbnum <= MVDS_location + ( MVDS_length - 1 )
               / DVD_VIDEO_LB_LEN ) && ( TagID != 8 )
             && ( !desc_found) );
    
    if( !desc_found ) {
      /* Backup volume descriptor */
      MVDS_location = avdp.rvds.location;
      MVDS_length = avdp.rvds.length;
    }
  } while( i-- && ( !desc_found )  );

  
  return desc_found;
}


static int UDFGetPVD(dvd_reader_t *device, struct pvd_t *pvd)
{
  uint8_t *pvd_buf;
  
  if(GetUDFCache(device, PVDCache, 0, pvd)) {
    return 1;
  }
  
  pvd_buf = dvdalign_lbmalloc(device, 1);
  if(!pvd_buf) {
    return 0;
  }
  if(!UDFGetDescriptor( device, 1, pvd_buf, 1*DVD_VIDEO_LB_LEN)) {
    dvdalign_lbfree(device, pvd_buf);
    return 0;
  }
  
  memcpy(pvd->VolumeIdentifier, &pvd_buf[24], 32);
  memcpy(pvd->VolumeSetIdentifier, &pvd_buf[72], 128);
  SetUDFCache(device, PVDCache, 0, pvd);
  
  dvdalign_lbfree(device, pvd_buf);

  return 1;
}

/**
 * Gets the Volume Identifier string, in 8bit unicode (latin-1)
 * volid, place to put the string
 * volid_size, size of the buffer volid points to
 * returns the size of buffer needed for all data
 */
int UDFGetVolumeIdentifier(dvd_reader_t *device, char *volid,
                           unsigned int volid_size)
{
  struct pvd_t pvd;
  unsigned int volid_len;

  /* get primary volume descriptor */
  if(!UDFGetPVD(device, &pvd)) {
    return 0;
  }

  volid_len = pvd.VolumeIdentifier[31];
  if(volid_len > 31) {
    /* this field is only 32 bytes something is wrong */
    volid_len = 31;
  }
  if(volid_size > volid_len) {
    volid_size = volid_len;
  }
  Unicodedecode(pvd.VolumeIdentifier, volid_size, volid);
  
  return volid_len;
}

/**
 * Gets the Volume Set Identifier, as a 128-byte dstring (not decoded)
 * WARNING This is not a null terminated string
 * volsetid, place to put the data
 * volsetid_size, size of the buffer volsetid points to 
 * the buffer should be >=128 bytes to store the whole volumesetidentifier
 * returns the size of the available volsetid information (128)
 * or 0 on error
 */
int UDFGetVolumeSetIdentifier(dvd_reader_t *device, uint8_t *volsetid,
                              unsigned int volsetid_size)
{
  struct pvd_t pvd;

  /* get primary volume descriptor */
  if(!UDFGetPVD(device, &pvd)) {
    return 0;
  }


  if(volsetid_size > 128) {
    volsetid_size = 128;
  }
  
  memcpy(volsetid, pvd.VolumeSetIdentifier, volsetid_size);
  
  return 128;
}