Method updateHeaderFooter

src/traffic_cache_tool/CacheDefs.cc:293–357

}

Errata
StripeSM::updateHeaderFooter()
{
  Errata zret;
  this->vol_init_data();

  int64_t hdr_size      = this->vol_headerlen();
  int64_t dir_size      = this->vol_dirlen();
  Bytes   footer_offset = Bytes(dir_size - ROUND_TO_STORE_BLOCK(sizeof(StripeMeta)));
  _meta_pos[A][HEAD]    = round_down(_start);
  _meta_pos[A][FOOT]    = round_down(_start + footer_offset);
  _meta_pos[B][HEAD]    = round_down(this->_start + Bytes(dir_size));
  _meta_pos[B][FOOT]    = round_down(this->_start + Bytes(dir_size) + footer_offset);
  std::cout << "updating header " << _meta_pos[0][0] << std::endl;
  std::cout << "updating header " << _meta_pos[0][1] << std::endl;
  std::cout << "updating header " << _meta_pos[1][0] << std::endl;
  std::cout << "updating header " << _meta_pos[1][1] << std::endl;
  InitializeMeta();

  if (!OPEN_RW_FLAG) {
    zret.note("Writing Not Enabled.. Please use --write to enable writing to disk");
    return zret;
  }

  char *meta_t = static_cast<char *>(ats_memalign(ats_pagesize(), dir_size));
  // copy headers
  for (auto i : {A, B}) {
    // copy header
    memcpy(meta_t, &_meta[i][HEAD], sizeof(StripeMeta));
    // copy freelist
    memcpy(meta_t + sizeof(StripeMeta) - sizeof(uint16_t), this->freelist, this->_segments * sizeof(uint16_t));

    ssize_t n = pwrite(_span->_fd, meta_t, hdr_size, _meta_pos[i][HEAD]);
    if (n < hdr_size) {
      zret = swoc::Errata(make_errno_code(), "Failed to write stripe header ");
      std::cout << "problem writing header to disk: " << strerror(errno) << ":" << " " << n << "<" << hdr_size << std::endl;
      ats_free(meta_t);
      return zret;
    }
    // copy dir entries
    dir_size = dir_size - hdr_size - ROUND_TO_STORE_BLOCK(sizeof(StripeMeta));
    memcpy(meta_t, (char *)dir, dir_size);
    n = pwrite(_span->_fd, meta_t, dir_size, _meta_pos[i][HEAD] + hdr_size); //
    if (n < dir_size) {
      zret = Errata(make_errno_code(), "Failed to write stripe header ");
      std::cout << "problem writing dir to disk: " << strerror(errno) << ":" << " " << n << "<" << dir_size << std::endl;
      ats_free(meta_t);
      return zret;
    }

    // copy footer,
    memcpy(meta_t, &_meta[i][FOOT], sizeof(StripeMeta));

    int64_t footer_size = ROUND_TO_STORE_BLOCK(sizeof(StripeMeta));
    n                   = pwrite(_span->_fd, meta_t, footer_size, _meta_pos[i][FOOT]);
    if (n < footer_size) {
      zret = Errata(make_errno_code(), "Failed to write stripe header ");
      std::cout << "problem writing footer to disk: " << strerror(errno) << ":" << " " << n << "<" << footer_size << std::endl;