long Cluster::GetFirst(const BlockEntry*& pFirst) const {
  if (m_entries_count <= 0) {
    long long pos;
    long len;

    const long status = Parse(pos, len);

    if (status < 0) {  // error
      pFirst = NULL;
      return status;
    }

    if (m_entries_count <= 0) {  // empty cluster
      pFirst = NULL;
      return 0;
    }
  }

  assert(m_entries);

  pFirst = m_entries[0];
  assert(pFirst);

  return 0;  // success
}
Unknown