Method handle_content_length_header

src/proxy/http/HttpTransact.cc:6664–6776

* handle_content_length_header(...) * Function handles the insertion of content length headers into * header. header CAN equal base. */

 * header. header CAN equal base.
 */
void
HttpTransact::handle_content_length_header(State *s, HTTPHdr *header, HTTPHdr *base)
{
  int64_t cl = HTTP_UNDEFINED_CL;
  ink_assert(header->type_get() == HTTP_TYPE_RESPONSE);
  if (base->presence(MIME_PRESENCE_CONTENT_LENGTH)) {
    cl = base->get_content_length();
    if (cl >= 0) {
      // header->set_content_length(cl);
      ink_assert(header->get_content_length() == cl);

      switch (s->source) {
      case SOURCE_HTTP_ORIGIN_SERVER:
        // We made our decision about whether to trust the
        //   response content length in init_state_vars_from_response()
        if (s->range_setup != HttpTransact::RANGE_NOT_TRANSFORM_REQUESTED) {
          break;
        }
        // fallthrough

      case SOURCE_CACHE:
        // if we are doing a single Range: request, calculate the new
        // C-L: header
        if (s->range_setup == HttpTransact::RANGE_NOT_TRANSFORM_REQUESTED) {
          change_response_header_because_of_range_request(s, header);
          s->hdr_info.trust_response_cl = true;
        }
        ////////////////////////////////////////////////
        //  Make sure that the cache's object size    //
        //   agrees with the Content-Length           //
        //   Otherwise, set the state's machine view  //
        //   of c-l to undefined to turn off K-A      //
        ////////////////////////////////////////////////
        else if (s->cache_info.object_read->object_size_get() == cl) {
          s->hdr_info.trust_response_cl = true;
        } else {
          TxnDbg(dbg_ctl_http_trans, "Content Length header and cache object size mismatch."
                                     "Disabling keep-alive");
          s->hdr_info.trust_response_cl = false;
        }
        break;

      case SOURCE_TRANSFORM:
        if (s->range_setup == HttpTransact::RANGE_REQUESTED) {
          header->set_content_length(s->range_output_cl);
          s->hdr_info.trust_response_cl = true;
        } else if (s->hdr_info.transform_response_cl == HTTP_UNDEFINED_CL) {
          s->hdr_info.trust_response_cl = false;
        } else {
          s->hdr_info.trust_response_cl = true;
        }
        break;

      default:
        ink_release_assert(0);
        break;
      }
    } else {