fsfw/datalinklayer/MapPacketExtraction.h

/**
 * @file	MapPacketExtraction.h
 * @brief	This file defines the MapPacketExtraction class.
 * @date	26.03.2013
 * @author	baetz
 */

#ifndef MAPPACKETEXTRACTION_H_
#define MAPPACKETEXTRACTION_H_

#include <framework/datalinklayer/MapPacketExtractionIF.h>
#include <framework/objectmanager/ObjectManagerIF.h>
#include <framework/returnvalues/HasReturnvaluesIF.h>
#include <framework/ipc/MessageQueueSenderIF.h>

class StorageManagerIF;

/**
 * Implementation of a MAP Packet Extraction class.
 * The class implements the full MAP Packet Extraction functionality as described in the CCSDS
 * TC Space Data Link Protocol. It internally stores incomplete segmented packets until they are
 * fully received. All found packets are forwarded to a single distribution entity.
 */
class MapPacketExtraction: public MapPacketExtractionIF {
private:
	static const uint32_t MAX_PACKET_SIZE = 4096;
	uint8_t lastSegmentationFlag;	//!< The segmentation flag of the last received frame.
	uint8_t mapId;	//!< MAP ID of this MAP Channel.
	uint32_t packetLength;	//!< Complete length of the current Space Packet.
	uint8_t* bufferPosition;	//!< Position to write to in the internal Packet buffer.
	uint8_t packetBuffer[MAX_PACKET_SIZE];	//!< The internal Space Packet Buffer.
	object_id_t packetDestination;
	StorageManagerIF* packetStore;	//!< Pointer to the store where full TC packets are stored.
	MessageQueueId_t tcQueueId;		//!< QueueId to send found packets to the distributor.
	/**
	 * Debug method to print the packet Buffer's content.
	 */
	void printPacketBuffer();
	/**
	 * Method that is called if the segmentation flag is @c NO_SEGMENTATION.
	 * The method extracts one or more packets within the frame and forwards them to the OBSW.
	 * @param frame	The TC Transfer Frame to work on.
	 * @return	@c RETURN_OK if all Packets were extracted. If something is entirely wrong,
	 * 	 @c DATA_CORRUPTED is returned, if some bytes are left over @c RESIDUAL_DATA.
	 */
	ReturnValue_t unpackBlockingPackets(TcTransferFrame* frame);
	/**
	 * Helper method to forward a complete packet to the OBSW.
	 * @param data	Pointer to the data, either directly from the frame or from the packetBuffer.
	 * @param size	Complete total size of the packet.
	 * @return	Return Code of the Packet Store or the Message Queue.
	 */
	ReturnValue_t sendCompletePacket( uint8_t* data, uint32_t size );
	/**
	 * Helper method to reset the internal buffer.
	 */
	void clearBuffers();
public:
	/**
	 * Default constructor.
	 * Members are set to default values.
	 * @param setMapId	The MAP ID of the instance.
	 */
	MapPacketExtraction( uint8_t setMapId, object_id_t setPacketDestination );
	ReturnValue_t extractPackets(TcTransferFrame* frame);
	/**
	 * The #packetStore and the default destination of #tcQueue are initialized here.
	 * @return	@c RETURN_OK on success, @c RETURN_FAILED otherwise.
	 */
	ReturnValue_t initialize();
	/**
	 * Getter.
	 * @return The MAP ID of this instance.
	 */
	uint8_t getMapId() const;
};

#endif /* MAPPACKETEXTRACTION_H_ */