anchor.diff:  
   
   %% @private
  --spec maybe_schedule_uploads_checkup(state()) -> state().
  -maybe_schedule_uploads_checkup(#state{checkup_timer = undefined} = State) ->
  +-spec schedule_uploads_checkup(state()) -> state().
  +schedule_uploads_checkup(#state{checkup_timer = undefined} = State) ->
       State#state{checkup_timer = erlang:send_after(
           ?UPLOADS_CHECKUP_INTERVAL, self(), ?CHECK_UPLOADS_REQ
       )};
  -maybe_schedule_uploads_checkup(State) ->
  +schedule_uploads_checkup(State) ->
       State.
   
   
  
positive.code: %%%===================================================================
  %%% Internal functions
  %%%===================================================================
  
  
  %% @private
  
negative.code: %%--------------------------------------------------------------------
  -spec handle_call(Request :: term(), From :: {pid(), Tag :: term()}, state()) ->
      {reply, Reply :: term(), NewState :: state()} |
      {reply, Reply :: term(), NewState :: state(), hibernate}.
  handle_call(?REGISTER_UPLOAD_REQ(UserId, FileGuid), _, #state{uploads = Uploads} = State) ->
      UploadCtx = #upload_ctx{
          user_id = UserId,
          monitors = ordsets:new(),
          latest_chunk_upload_ended_timestamp = ?NOW()
      },  %% TODO check if not registered ?
      reply(ok, State#state{uploads = Uploads#{FileGuid => UploadCtx}});
  
  handle_call(?AUTHORIZE_CHUNK_UPLOAD(UserId, FileGuid), {ClientPid, _}, State = #state{
      uploads = Uploads,
      monitor_to_file_mapping = MonitorToFileMapping
  }) ->
      case maps:find(FileGuid, Uploads) of
          {ok, #upload_ctx{user_id = UserId, monitors = Monitors} = UploadCtx} ->
              Monitor = erlang:monitor(process, ClientPid),
              NewUploadCtx = UploadCtx#upload_ctx{monitors = ordsets:add_element(
                  Monitor, Monitors
              )},
              reply(true, State#state{
                  uploads = Uploads#{FileGuid => NewUploadCtx},
                  monitor_to_file_mapping = MonitorToFileMapping#{Monitor => FileGuid}
              });
          _ ->
              reply(false, State)
      end;
  
  handle_call(Request, _From, State) ->
      ?log_bad_request(Request),
      reply({error, wrong_request}, State).
  
  
  %%--------------------------------------------------------------------
  