Function state_write_to_cache

example/plugins/c-api/protocol/TxnSM.cc:677–730

If the whole doc has been written into the cache, send the response to the client, otherwise, reenable the read_vio. */

/* If the whole doc has been written into the cache, send the response
   to the client, otherwise, reenable the read_vio. */
int
state_write_to_cache(TSCont contp, TSEvent event, TSVIO vio)
{
  TxnSM *txn_sm = static_cast<TxnSM *>(TSContDataGet(contp));

  Dbg(dbg_ctl, "enter state_write_to_cache");

  switch (event) {
  case TS_EVENT_VCONN_WRITE_READY:
    TSVIOReenable(txn_sm->q_cache_write_vio);
    return TS_SUCCESS;

  case TS_EVENT_VCONN_WRITE_COMPLETE:
    Dbg(dbg_ctl, "nbytes %" PRId64 ", ndone %" PRId64, TSVIONBytesGet(vio), TSVIONDoneGet(vio));
    /* Since the first write is through TSVConnWrite, which already consume
       the data in cache_buffer_reader, don't consume it again. */
    if (txn_sm->q_cache_response_length > 0 && txn_sm->q_block_bytes_read > 0) {
      TSIOBufferReaderConsume(txn_sm->q_cache_response_buffer_reader, txn_sm->q_block_bytes_read);
    }

    txn_sm->q_cache_response_length += TSVIONBytesGet(vio);

    /* If not all data have been read in, we have to reenable the read_vio */
    if (txn_sm->q_server_vc != nullptr) {
      Dbg(dbg_ctl, "re-enable server_read_vio");
      TSVIOReenable(txn_sm->q_server_read_vio);
      return TS_SUCCESS;
    }

    if (txn_sm->q_cache_response_length >= txn_sm->q_server_response_length) {
      /* Write is complete, close the cache_vc. */
      Dbg(dbg_ctl, "close cache_vc, cache_response_length is %d, server_response_length is %d", txn_sm->q_cache_response_length,
          txn_sm->q_server_response_length);
      TSVConnClose(txn_sm->q_cache_vc);
      txn_sm->q_cache_vc        = nullptr;
      txn_sm->q_cache_write_vio = nullptr;
      TSIOBufferReaderFree(txn_sm->q_cache_response_buffer_reader);

      /* Open cache_vc to read data and send to client. */
      set_handler(txn_sm->q_current_handler, (TxnSMHandler)&state_handle_cache_lookup);
      txn_sm->q_pending_action = TSCacheRead(contp, txn_sm->q_key);
    } else { /* not done with writing into cache */

      Dbg(dbg_ctl, "re-enable cache_write_vio");
      TSVIOReenable(txn_sm->q_cache_write_vio);
    }
    return TS_SUCCESS;
  default:
    break;
  }

  /* Something wrong if getting here. */
  return prepare_to_die(contp);
}

/* If the response has been fully written into the client_vc,
   which means this txn is done, close the client_vc. Otherwise,