fsfw/osal/FreeRTOS/BinarySemaphore.h

#ifndef FRAMEWORK_OSAL_FREERTOS_BINARYSEMPAHORE_H_
#define FRAMEWORK_OSAL_FREERTOS_BINARYSEMPAHORE_H_

#include <framework/returnvalues/HasReturnvaluesIF.h>
#include <framework/tasks/SemaphoreIF.h>

#include <freertos/FreeRTOS.h>
#include <freertos/semphr.h>

/**
 * @brief 	OS Tool to achieve synchronization of between tasks or between
 * 			task and ISR. The default semaphore implementation creates a
 * 			binary semaphore, which can only be taken once.
 * @details
 * Documentation: https://www.freertos.org/Embedded-RTOS-Binary-Semaphores.html
 *
 * Please note that if the semaphore implementation is only related to
 * the synchronization of one task, the new task notifications can be used,
 * also see the BinSemaphUsingTask and CountingSemaphUsingTask classes.
 * These use the task notification value instead of a queue and are
 * faster and more efficient.
 *
 * @author 	R. Mueller
 * @ingroup osal
 */
class BinarySemaphore: public SemaphoreIF,
		public HasReturnvaluesIF {
public:
	static const uint8_t INTERFACE_ID = CLASS_ID::SEMAPHORE_IF;

	//! @brief Default ctor
	BinarySemaphore();
	//! @brief Copy ctor, deleted explicitely.
	BinarySemaphore(const BinarySemaphore&) = delete;
	//! @brief Copy assignment, deleted explicitely.
	BinarySemaphore& operator=(const BinarySemaphore&) = delete;
	//! @brief Move ctor
	BinarySemaphore (BinarySemaphore &&);
	//! @brief Move assignment
	BinarySemaphore & operator=(BinarySemaphore &&);
	//! @brief Destructor
	virtual ~BinarySemaphore();

	uint8_t getSemaphoreCounter() const override;

	/**
	 * Take the binary semaphore.
	 * If the semaphore has already been taken, the task will be blocked
	 * for a maximum of #timeoutMs or until the semaphore is given back,
	 * for example by an ISR or another task.
	 * @param timeoutMs
	 * @return -@c RETURN_OK on success
	 *         -@c SemaphoreIF::SEMAPHORE_TIMEOUT on timeout
	 */
	ReturnValue_t acquire(uint32_t timeoutMs =
	       	   SemaphoreIF::NO_TIMEOUT) override;

	/**
	 * Same as lockBinarySemaphore() with timeout in FreeRTOS ticks.
	 * @param timeoutTicks
	 * @return -@c RETURN_OK on success
	 *         -@c SemaphoreIF::SEMAPHORE_TIMEOUT on timeout
	 */
	ReturnValue_t  acquireWithTickTimeout(TickType_t timeoutTicks =
	        BinarySemaphore::NO_TIMEOUT);

	/**
	 * Release the binary semaphore.
	 * @return -@c RETURN_OK on success
	 *         -@c SemaphoreIF::SEMAPHORE_NOT_OWNED if the semaphores is
	 *         	already available.
	 */
	ReturnValue_t release() override;

	/**
	 * Get Handle to the semaphore.
	 * @return
	 */
	SemaphoreHandle_t getSemaphore();

	 /**
	 * Wrapper function to give back semaphore from handle
	 * @param semaphore
	 * @return -@c RETURN_OK on success
	 *         -@c SemaphoreIF::SEMAPHORE_NOT_OWNED if the semaphores is
	 *         	already available.
	 */
	static ReturnValue_t release(SemaphoreHandle_t semaphore);

	/**
	 * Wrapper function to give back semaphore from handle when called from an ISR
	 * @param semaphore
	 * @param higherPriorityTaskWoken This will be set to pdPASS if a task with
	 * a higher priority was unblocked. A context switch from an ISR should
	 * then be requested (see TaskManagement functions)
	 * @return -@c RETURN_OK on success
	 *         -@c SemaphoreIF::SEMAPHORE_NOT_OWNED if the semaphores is
	 *         	already available.
	 */
	static ReturnValue_t releaseFromISR(SemaphoreHandle_t semaphore,
				BaseType_t * higherPriorityTaskWoken);

protected:
	SemaphoreHandle_t handle;
};

#endif /* FRAMEWORK_OSAL_FREERTOS_BINARYSEMPAHORE_H_ */