fsfw/src/fsfw/tcdistribution/TcDistributorBase.h

#ifndef FSFW_TMTCSERVICES_TCDISTRIBUTOR_H_
#define FSFW_TMTCSERVICES_TCDISTRIBUTOR_H_

#include <map>

#include "fsfw/events/Event.h"
#include "fsfw/ipc/MessageQueueIF.h"
#include "fsfw/objectmanager/ObjectManagerIF.h"
#include "fsfw/objectmanager/SystemObject.h"
#include "fsfw/returnvalues/HasReturnvaluesIF.h"
#include "fsfw/storagemanager/StorageManagerIF.h"
#include "fsfw/tasks/ExecutableObjectIF.h"
#include "fsfw/tmtcservices/TmTcMessage.h"

/**
 * @defgroup tc_distribution Telecommand Distribution
 * All classes associated with Routing and Distribution of Telecommands
 * belong to this group.
 */

/**
 * This is the base class to implement distributors for telecommands.
 * Typically, the distribution is required to forward telecommand packets
 * over the satellite applications and services. The class receives
 * TC packets over a message queue and holds a map that links other
 * message queue IDs to some identifier. The process of unpacking the
 * destination information from the packet is handled by the child class
 * implementations.
 * @ingroup tc_distribution
 */
class TcDistributorBase : public SystemObject, public ExecutableObjectIF, public HasReturnvaluesIF {
 public:
  static constexpr uint8_t INTERFACE_ID = CLASS_ID::PACKET_DISTRIBUTION;
  static constexpr ReturnValue_t PACKET_LOST = MAKE_RETURN_CODE(1);
  static constexpr ReturnValue_t DESTINATION_NOT_FOUND = MAKE_RETURN_CODE(2);
  static constexpr ReturnValue_t SERVICE_ID_ALREADY_EXISTS = MAKE_RETURN_CODE(3);

  static constexpr uint8_t SUBSYSTEM_ID = SUBSYSTEM_ID::TC_DISTRIBUTION;
  //! P1: Returnvalue, P2: Line number
  static constexpr Event HANDLE_PACKET_FAILED = event::makeEvent(SUBSYSTEM_ID, 0, severity::LOW);
  /**
   * Within the default constructor, the SystemObject id is set and the
   * message queue is initialized.
   * Filling the map is under control of the child classes.
   * @param set_object_id	This id is assigned to the distributor
   * 		implementation.
   */
  explicit TcDistributorBase(object_id_t objectId, MessageQueueIF* tcQueue = nullptr);
  /**
   * The destructor is empty, the message queues are not in the vicinity of
   * this class.
   */
  ~TcDistributorBase() override;
  /**
   * The method is called cyclically and fetches new incoming packets from
   * the message queue.
   * In case a new packet is found, it calls the handlePacket method to deal
   * with distribution.
   * @return The error code of the message queue call.
   */
  ReturnValue_t performOperation(uint8_t opCode) override;

 protected:
  bool ownedQueue = false;
  /**
   * This is the receiving queue for incoming Telecommands.
   * The child classes must make its queue id public.
   */
  MessageQueueIF* tcQueue = nullptr;
  /**
   * The last received incoming packet information is stored in this
   * member.
   * As different child classes unpack the incoming packet differently
   * (i.e. as a CCSDS Space Packet or as a PUS Telecommand Packet), no unpacking will be
   * done in this class.
   */
  TmTcMessage currentMessage;

  /**
   * This method shall unpack the routing information from the incoming
   * packet and select the map entry which represents the packet's target.
   * @return
   *  - @c RETURN_OK if a desitnation was selected successfully
   */
  virtual ReturnValue_t selectDestination(MessageQueueId_t& destId) = 0;
  /**
   * The handlePacket method calls the child class's selectDestination method
   * and forwards the packet to its destination, if found.
   * @return The message queue return value or @c RETURN_FAILED, in case no
   * 		destination was found.
   */
  ReturnValue_t handlePacket();
  /**
   * This method gives the child class a chance to perform some kind of
   * operation after the parent tried to forward the message.
   * A typically application would be sending success/failure messages.
   * The default implementation just returns @c RETURN_OK.
   * @param queueStatus	The status of the message queue after an attempt
   *                      to send the TC.
   * @return	- @c RETURN_OK on success
   * 			- @c RETURN_FAILED on failure
   */
  virtual ReturnValue_t callbackAfterSending(ReturnValue_t queueStatus);

 private:
  /**
   * This constant sets the maximum number of packets distributed per call.
   */
  static constexpr uint8_t DISTRIBUTER_MAX_PACKETS = 128;
};

#endif /* FSFW_TMTCSERVICES_TCDISTRIBUTOR_H_ */