/** * @file MultiObjectTask.h * @brief This file defines the MultiObjectTask class. * @date 30.01.2014 * @author baetz */ #ifndef MULTIOBJECTTASK_H_ #define MULTIOBJECTTASK_H_ #include #include #include #include /** * @brief This class represents a specialized task for periodic activities of multiple objects. * * @details MultiObjectTask is an extension to ObjectTask in the way that it is able to execute * multiple objects that implement the ExecutableObjectIF interface. The objects must be * added prior to starting the task. * * @ingroup task_handling */ class MultiObjectTask: public TaskBase { protected: typedef std::list ObjectList; //!< Typedef for the List of objects. /** * @brief This attribute holds a list of objects to be executed. */ ObjectList objectList; /** * @brief The period of the task. * @details The period determines the frequency of the task's execution. It is expressed in clock ticks. */ Interval_t period; /** * @brief id of the associated OS period */ PeriodId_t periodId; /** * @brief The pointer to the deadline-missed function. * @details This pointer stores the function that is executed if the task's deadline is missed. * So, each may react individually on a timing failure. The pointer may be NULL, * then nothing happens on missing the deadline. The deadline is equal to the next execution * of the periodic task. */ void (*deadlineMissedFunc)(void); /** * @brief This is the function executed in the new task's context. * @details It converts the argument back to the thread object type and copies the class instance * to the task context. The taskFunctionality method is called afterwards. * @param A pointer to the task object itself is passed as argument. */ static TaskReturn_t taskEntryPoint(TaskArgument_t argument); /** * @brief The function containing the actual functionality of the task. * @details The method sets and starts * the task's period, then enters a loop that is repeated as long as the isRunning * attribute is true. Within the loop, all performOperation methods of the added * objects are called. Afterwards the checkAndRestartPeriod system call blocks the task * until the next period. * On missing the deadline, the deadlineMissedFunction is executed. */ void taskFunctionality(void); public: /** * @brief Standard constructor of the class. * @details The class is initialized without allocated objects. These need to be added * with #addObject. * In the underlying TaskBase class, a new operating system task is created. * In addition to the TaskBase parameters, the period, the pointer to the * aforementioned initialization function and an optional "deadline-missed" * function pointer is passed. * @param priority Sets the priority of a task. Values range from a low 0 to a high 99. * @param stack_size The stack size reserved by the operating system for the task. * @param setPeriod The length of the period with which the task's functionality will be * executed. It is expressed in clock ticks. * @param setDeadlineMissedFunc The function pointer to the deadline missed function * that shall be assigned. */ MultiObjectTask(const char *name, TaskPriority_t setPriority, size_t setStack, Interval_t setPeriod, void (*setDeadlineMissedFunc)()); /** * @brief Currently, the executed object's lifetime is not coupled with the task object's * lifetime, so the destructor is empty. */ virtual ~MultiObjectTask(void); /** * @brief The method to start the task. * @details The method starts the task with the respective system call. * Entry point is the taskEntryPoint method described below. * The address of the task object is passed as an argument * to the system call. */ ReturnValue_t startTask(void); /** * Adds an object to the list of objects to be executed. * The objects are executed in the order added. * @param object Id of the object to add. * @return RETURN_OK on success, RETURN_FAILED if the object could not be added. */ ReturnValue_t addObject(object_id_t object); /** * Variant to add objects with known location directly. * @param object Reference to a persistant executable object. * @return RETURN_OK on success, RETURN_FAILED if the object could not be added. */ ReturnValue_t addObject(ExecutableObjectIF* object); }; #endif /* MULTIOBJECTTASK_H_ */