Method merge_warning_header

src/proxy/http/HttpTransact.cc:5091–5161

}

void
HttpTransact::merge_warning_header(HTTPHdr *cached_header, HTTPHdr *response_header)
{
  //  The plan:
  //
  //    1) The cached header has it's warning codes untouched
  //         since merge_response_header_with_cached_header()
  //         doesn't deal with warning headers.
  //    2) If there are 1xx warning codes in the cached
  //         header, they need to be removed.  Removal
  //         is difficult since the hdrs don't comma
  //         separate values, so build up a new header
  //         piecemeal.  Very slow but shouldn't happen
  //         very often
  //    3) Since we keep the all the warning codes from
  //         the response header, append if to
  //         the cached header
  //
  MIMEField  *c_warn    = cached_header->field_find(MIME_FIELD_WARNING, MIME_LEN_WARNING);
  MIMEField  *r_warn    = response_header->field_find(MIME_FIELD_WARNING, MIME_LEN_WARNING);
  MIMEField  *new_cwarn = nullptr;
  int         move_warn_len;
  const char *move_warn;

  // Loop over the cached warning header and transfer all non 1xx
  //   warning values to a new header
  if (c_warn) {
    HdrCsvIter csv;

    move_warn = csv.get_first(c_warn, &move_warn_len);
    while (move_warn) {
      int code = ink_atoi(move_warn, move_warn_len);
      if (code < 100 || code > 199) {
        bool first_move;
        if (!new_cwarn) {
          new_cwarn  = cached_header->field_create();
          first_move = true;
        } else {
          first_move = false;
        }
        cached_header->field_value_append(new_cwarn, move_warn, move_warn_len, !first_move);
      }

      move_warn = csv.get_next(&move_warn_len);
    }

    // At this point we can nuke the old warning headers
    cached_header->field_delete(MIME_FIELD_WARNING, MIME_LEN_WARNING);

    // Add in the new header if it has anything in it
    if (new_cwarn) {
      new_cwarn->name_set(cached_header->m_heap, cached_header->m_mime, MIME_FIELD_WARNING, MIME_LEN_WARNING);
      cached_header->field_attach(new_cwarn);
    }
  }
  // Loop over all the dups in the response warning header and append
  //  them one by one on to the cached warning header
  while (r_warn) {