Method state_common_wait_for_transform_read

src/proxy/http/HttpSM.cc:1229–1312

int HttpSM::state_common_wait_for_transform_read(...) This function handles the overlapping cases between request and response transforms which prevents code duplication

//     transforms which prevents code duplication
//
int
HttpSM::state_common_wait_for_transform_read(HttpTransformInfo *t_info, HttpSMHandler tunnel_handler, int event, void *data)
{
  STATE_ENTER(&HttpSM::state_common_wait_for_transform_read, event);
  HttpTunnelConsumer *c = nullptr;

  switch (event) {
  case HTTP_TUNNEL_EVENT_DONE:
    // There are three reasons why the tunnel could signal completed
    //   1) there was error from the transform write
    //   2) there was an error from the data source
    //   3) the transform write completed before it sent
    //      TRANSFORM_READ_READY which is legal and in which
    //      case we should just wait for the transform read ready
    c = tunnel.get_consumer(t_info->vc);
    ink_assert(c != nullptr);
    ink_assert(c->vc == t_info->entry->vc);

    if (c->handler_state == HTTP_SM_TRANSFORM_FAIL) {
      // Case 1 we failed to complete the write to the
      //  transform fall through to vc event error case
      ink_assert(c->write_success == false);
    } else if (c->producer->read_success == false) {
      // Case 2 - error from data source
      if (c->producer->vc_type == HT_HTTP_CLIENT) {
        // Our source is the client.  POST can't
        //   be truncated so forward to the tunnel
        //   handler to clean this mess up
        ink_assert(t_info == &post_transform_info);
        return (this->*tunnel_handler)(event, data);
      } else {
        // On the response side, we just forward as much
        //   as we can of truncated documents so
        //   just don't cache the result
        ink_assert(t_info == &transform_info);
        t_state.api_info.cache_transformed = false;
        return 0;
      }
    } else {
      // Case 3 - wait for transform read ready
      return 0;
    }
  // FALLTHROUGH
  case VC_EVENT_ERROR:
  case VC_EVENT_EOS:
  case VC_EVENT_INACTIVITY_TIMEOUT:
    // Transform VC sends NULL on error conditions
    if (!c) {
      c = tunnel.get_consumer(t_info->vc);
      ink_assert(c != nullptr);
    }
    vc_table.cleanup_entry(t_info->entry);
    t_info->entry = nullptr;
    // In Case 1: error due to transform write,
    // we need to keep the original t_info->vc for transform_cleanup()
    // to skip do_io_close(); otherwise, set it to NULL.
    if (c->handler_state != HTTP_SM_TRANSFORM_FAIL) {
      t_info->vc = nullptr;