UncompressedData.fromBlob constructor

UncompressedData.fromBlob(List<int> rawBytes)

Implementation

factory UncompressedData.fromBlob(List<int> rawBytes) {
  if (rawBytes.isEmpty) {
    throw WinmdException('Bad signature');
  }

  // Smallest -- one byte
  if ((rawBytes[0] & 0x80) == 0x00) // 0??? ????
  {
    final value = rawBytes[0];
    final length = 1;
    return UncompressedData(value, length);
  }

  // Medium -- two bytes
  else if ((rawBytes[0] & 0xC0) == 0x80) // 10?? ????
  {
    if (rawBytes.length < 2) {
      throw WinmdException('Bad signature');
    } else {
      final value = (rawBytes[0] & 0x3f) << 8 | rawBytes[1];
      final length = 2;
      return UncompressedData(value, length);
    }
  }

  // Large -- four bytes
  else if ((rawBytes[0] & 0xE0) == 0xC0) // 110? ????
  {
    if (rawBytes.length < 4) {
      throw WinmdException('Bad signature');
    } else {
      final value = (rawBytes[0] & 0x1f) << 24 |
          (rawBytes[1]) << 16 |
          (rawBytes[2]) << 8 |
          (rawBytes[3]);
      final length = 4;
      return UncompressedData(value, length);
    }
  } else // We don't recognize this encoding
  {
    throw WinmdException('Bad signature');
  }
}