fsfw/tmtcpacket/pus/TmPacketBase.h

#ifndef TMTCPACKET_PUS_TMPACKETBASE_H_
#define TMTCPACKET_PUS_TMPACKETBASE_H_

#include "../SpacePacketBase.h"
#include "../../timemanager/TimeStamperIF.h"
#include "../../timemanager/Clock.h"
#include "../../objectmanager/SystemObjectIF.h"

namespace Factory{
void setStaticFrameworkObjectIds();
}


/**
 * This class is the basic data handler for any ECSS PUS Telemetry packet.
 *
 * In addition to #SpacePacketBase, the class provides methods to handle
 * the standardized entries of the PUS TM Packet Data Field Header.
 * It does not contain the packet data itself but a pointer to the
 * data must be set on instantiation. An invalid pointer may cause
 * damage, as no getter method checks data validity. Anyway, a NULL
 * check can be performed by making use of the getWholeData method.
 * @ingroup tmtcpackets
 */
class TmPacketBase : public SpacePacketBase {
    friend void (Factory::setStaticFrameworkObjectIds)();
public:

    //! Maximum size of a TM Packet in this mission.
    //! TODO: Make this dependant on a config variable.
    static const uint32_t MISSION_TM_PACKET_MAX_SIZE = 2048;
    //! First byte of secondary header for PUS-A packets.
    //! TODO: Maybe also support PUS-C via config?
    static const uint8_t VERSION_NUMBER_BYTE = 0b00010000;

    /**
     * This is the default constructor.
     * It sets its internal data pointer to the address passed and also
     * forwards the data pointer to the parent SpacePacketBase class.
     * @param set_address	The position where the packet data lies.
     */
    TmPacketBase( uint8_t* setData );
    /**
     * This is the empty default destructor.
     */
    virtual ~TmPacketBase();

    /**
     * This is a getter for the packet's PUS Service ID, which is the second
     * byte of the Data Field Header.
     * @return	The packet's PUS Service ID.
     */
    virtual uint8_t getService() = 0;
    /**
     * This is a getter for the packet's PUS Service Subtype, which is the
     * third byte of the Data Field Header.
     * @return	The packet's PUS Service Subtype.
     */
    virtual uint8_t getSubService() = 0;
    /**
     * This is a getter for a pointer to the packet's Source data.
     *
     * These are the bytes that follow after the Data Field Header. They form
     * the packet's source data.
     * @return	A pointer to the PUS Source Data.
     */
    virtual uint8_t* getSourceData() = 0;
    /**
     * This method calculates the size of the PUS Source data field.
     *
     * It takes the information stored in the CCSDS Packet Data Length field
     * and subtracts the Data Field Header size and the CRC size.
     * @return	The size of the PUS Source Data (without Error Control field)
     */
    virtual uint16_t getSourceDataSize() = 0;

    /**
     * Get size of data field which can differ based on implementation
     * @return
     */
    virtual uint16_t getDataFieldSize() = 0;

    virtual size_t getPacketMinimumSize() const = 0;

    /**
     * Interprets the "time"-field in the secondary header and returns it in
     * timeval format.
     * @return Converted timestamp of packet.
     */
    virtual ReturnValue_t getPacketTime(timeval* timestamp) const = 0;
    /**
     * Returns a raw pointer to the beginning of the time field.
     * @return Raw pointer to time field.
     */
    virtual uint8_t* getPacketTimeRaw() const = 0;

    virtual size_t getTimestampSize() const = 0;

    /**
     * This is a debugging helper method that prints the whole packet content
     * to the screen.
     */
    void print();
    /**
     * With this method, the Error Control Field is updated to match the
     * current content of the packet. This method is not protected because
     * a recalculation by the user might be necessary when manipulating fields
     * like the sequence count.
     */
    void setErrorControl();
    /**
     * This getter returns the Error Control Field of the packet.
     *
     * The field is placed after any possible Source Data. If no
     * Source Data is present there's still an Error Control field. It is
     * supposed to be a 16bit-CRC.
     * @return  The PUS Error Control
     */
    uint16_t getErrorControl();

protected:
    /**
     * The timeStamper is responsible for adding a timestamp to the packet.
     * It is initialized lazy.
     */
    static TimeStamperIF* timeStamper;
    //! The ID to use when looking for a time stamper.
    static object_id_t timeStamperId;

    /**
     * Checks if a time stamper is available and tries to set it if not.
     * @return Returns false if setting failed.
     */
    bool checkAndSetStamper();
};


#endif /* TMTCPACKET_PUS_TMPACKETBASE_H_ */