@Override
  public void reset() throws IOException {
    if (in.markSupported()) {
      in.reset();
      mTailOffset = mMarkedTailOffset;
    } else {
      throw new IOException("mark is not supported");
    }
  }
InputStream that returns all bytes from another stream, then appends the specified 'tail' bytes.
fbcore/src/main/java/com/facebook/common/streams/TailAppendingInputStream.java