Method resolve_custom_entry

src/proxy/logging/LogBuffer.cc:484–581

------------------------------------------------------------------------- LogBuffer::resolve_custom_entry -------------------------------------------------------------------------*/

  LogBuffer::resolve_custom_entry
  -------------------------------------------------------------------------*/
int
LogBuffer::resolve_custom_entry(LogFieldList *fieldlist, char *printf_str, char *read_from, char *write_to, int write_to_len,
                                long /* timestamp ATS_UNUSED */, long /* timestamp_usec ATS_UNUSED */,
                                unsigned /* buffer_version ATS_UNUSED */, LogFieldList *alt_fieldlist, char *alt_printf_str,
                                LogEscapeType escape_type)
{
  if (fieldlist == nullptr || printf_str == nullptr) {
    return 0;
  }

  int *readfrom_map = nullptr;

  if (alt_fieldlist && alt_printf_str) {
    LogField *f, *g;
    int       n_alt_fields = alt_fieldlist->count();
    int       i            = 0;

    readfrom_map = static_cast<int *>(ats_malloc(n_alt_fields * sizeof(int)));
    for (f = alt_fieldlist->first(); f; f = alt_fieldlist->next(f)) {
      int  readfrom_pos = 0;
      bool found_match  = false;
      for (g = fieldlist->first(); g; g = fieldlist->next(g)) {
        if (strcmp(f->symbol(), g->symbol()) == 0) {
          found_match       = true;
          readfrom_map[i++] = readfrom_pos;
          break;
        }
        // TODO handle readfrom_pos properly
        // readfrom_pos += g->size();
      }
      if (!found_match) {
        Note("Alternate format contains a field (%s) not in the "
             "format logged",
             f->symbol());
        break;
      }
    }
  }
  //
  // Loop over the printf_str, copying everything to the write_to buffer
  // except the LOG_FIELD_MARKER characters.  When we reach those, we
  // substitute the string from the unmarshal routine of the current
  // LogField object, obtained from the fieldlist.
  //

  LogField *field         = fieldlist->first();
  LogField *lastField     = nullptr;                                // For debug message.
  int       markCount     = 0;                                      // For debug message.
  int       printf_len    = static_cast<int>(::strlen(printf_str)); // OPTIMIZE
  int       bytes_written = 0;
  int       res, i;

  const char *buffer_size_exceeded_msg = "Traffic Server is skipping the current log entry because its size "
                                         "exceeds the maximum line (entry) size for an ascii log buffer";

  for (i = 0; i < printf_len; i++) {
    if (printf_str[i] == LOG_FIELD_MARKER) {
      ++markCount;