fsfw/osal/host/PeriodicTask.h

#ifndef FRAMEWORK_OSAL_HOST_PERIODICTASK_H_
#define FRAMEWORK_OSAL_HOST_PERIODICTASK_H_

#include "../../objectmanager/ObjectManagerIF.h"
#include "../../tasks/PeriodicTaskIF.h"
#include "../../tasks/Typedef.h"

#include <vector>
#include <thread>
#include <condition_variable>
#include <atomic>

class ExecutableObjectIF;

/**
 * @brief 	This class represents a specialized task for
 * 			periodic activities of multiple objects.
 * @details
 *
 * @ingroup task_handling
 */
class PeriodicTask: public PeriodicTaskIF {
public:
	/**
	 * @brief	Standard constructor of the class.
	 * @details
	 * The class is initialized without allocated objects. These need to be
	 * added with #addComponent.
	 * @param priority
	 * @param stack_size
	 * @param setPeriod
	 * @param setDeadlineMissedFunc
	 * The function pointer to the deadline missed function that shall be
	 * assigned.
	 */
	PeriodicTask(const char *name, TaskPriority setPriority, TaskStackSize setStack,
			TaskPeriod 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 ~PeriodicTask(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
	 *  -@c RETURN_OK on success
	 *  -@c RETURN_FAILED if the object could not be added.
	 */
	ReturnValue_t addComponent(object_id_t object);

	uint32_t getPeriodMs() const;

	ReturnValue_t sleepFor(uint32_t ms);

protected:
	using chron_ms = std::chrono::milliseconds;
	bool started;
	//!< Typedef for the List of objects.
	typedef std::vector<ExecutableObjectIF*> ObjectList;
	std::thread mainThread;
	std::atomic<bool> terminateThread = false;

	/**
	 * @brief	This attribute holds a list of objects to be executed.
	 */
	ObjectList objectList;

	std::condition_variable initCondition;
	std::mutex initMutex;
	std::string taskName;
	/**
	 * @brief	The period of the task.
	 * @details
	 * The period determines the frequency of the task's execution.
	 * It is expressed in clock ticks.
	 */
	TaskPeriod period;
	/**
	 * @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.
	 */

	void taskEntryPoint(void* 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);

	bool delayForInterval(chron_ms * previousWakeTimeMs,
	        const chron_ms interval);
};

#endif /* PERIODICTASK_H_ */