fsfw/datapool/PoolDataSetBase.h

171 lines
6.2 KiB
C++

#ifndef FSFW_DATAPOOL_POOLDATASETBASE_H_
#define FSFW_DATAPOOL_POOLDATASETBASE_H_
#include "PoolDataSetIF.h"
#include "PoolVariableIF.h"
#include "../ipc/MutexIF.h"
/**
* @brief The DataSetBase class manages a set of locally checked out variables.
* @details
* This class manages a list, where a set of local variables (or pool variables)
* are registered. They are checked-out (i.e. their values are looked
* up and copied) with the read call. After the user finishes working with the
* pool variables, he can write back all variable values to the pool with
* the commit call. The data set manages locking and freeing the data pool,
* to ensure that all values are read and written back at once.
*
* An internal state manages usage of this class. Variables may only be
* registered before the read call is made, and the commit call only
* after the read call.
*
* If pool variables are writable and not committed until destruction
* of the set, the DataSet class automatically sets the valid flag in the
* data pool to invalid (without) changing the variable's value.
*
* The base class lockDataPool und unlockDataPool implementation are empty
* and should be implemented to protect the underlying pool type.
* @author Bastian Baetz
* @ingroup data_pool
*/
class PoolDataSetBase: public PoolDataSetIF,
public SerializeIF,
public HasReturnvaluesIF {
public:
/**
* @brief Creates an empty dataset. Use registerVariable or
* supply a pointer to this dataset to PoolVariable
* initializations to register pool variables.
*/
PoolDataSetBase(PoolVariableIF** registeredVariablesArray,
const size_t maxFillCount);
virtual~ PoolDataSetBase();
/**
* @brief The read call initializes reading out all registered variables.
* It is mandatory to call commit after every read call!
* @details
*
* TODO: Write RAII helper so user can not forget to call commit anymore.
*
* It iterates through the list of registered variables and calls all read()
* functions of the registered pool variables (which read out their values
* from the data pool) which are not write-only.
* In case of an error (e.g. a wrong data type, or an invalid data pool id),
* the operation is aborted and @c INVALID_PARAMETER_DEFINITION returned.
*
* The data pool is locked during the whole read operation and
* freed afterwards. It is mandatory to call commit after a read call,
* even if the read operation is not successful!
* @return
* - @c RETURN_OK if all variables were read successfully.
* - @c INVALID_PARAMETER_DEFINITION if a pool entry does not exist or there
* is a type conflict.
* - @c SET_WAS_ALREADY_READ if read() is called twice without calling
* commit() in between
*/
virtual ReturnValue_t read(uint32_t lockTimeout =
MutexIF::BLOCKING) override;
/**
* @brief The commit call initializes writing back the registered variables.
* @details
* It iterates through the list of registered variables and calls the
* commit() method of the remaining registered variables (which write back
* their values to the pool).
*
* The data pool is locked during the whole commit operation and
* freed afterwards. The state changes to "was committed" after this operation.
*
* If the set does contain at least one variable which is not write-only
* commit() can only be called after read(). If the set only contains
* variables which are write only, commit() can be called without a
* preceding read() call. Every read call must be followed by a commit call!
* @return - @c RETURN_OK if all variables were read successfully.
* - @c COMMITING_WITHOUT_READING if set was not read yet and
* contains non write-only variables
*/
virtual ReturnValue_t commit(uint32_t lockTimeout =
MutexIF::BLOCKING) override;
/**
* Register the passed pool variable instance into the data set.
* @param variable
* @return
*/
virtual ReturnValue_t registerVariable( PoolVariableIF* variable) override;
/**
* Provides the means to lock the underlying data structure to ensure
* thread-safety. Default implementation is empty
* @return Always returns -@c RETURN_OK
*/
virtual ReturnValue_t lockDataPool(uint32_t timeoutMs =
MutexIF::BLOCKING) override;
/**
* Provides the means to unlock the underlying data structure to ensure
* thread-safety. Default implementation is empty
* @return Always returns -@c RETURN_OK
*/
virtual ReturnValue_t unlockDataPool() override;
virtual uint16_t getFillCount() const;
/* SerializeIF implementations */
virtual ReturnValue_t serialize(uint8_t** buffer, size_t* size,
const size_t maxSize,
SerializeIF::Endianness streamEndianness) const override;
virtual size_t getSerializedSize() const override;
virtual ReturnValue_t deSerialize(const uint8_t** buffer, size_t* size,
SerializeIF::Endianness streamEndianness) override;
protected:
/**
* Can be used to individually protect every read and commit call.
* @param protectEveryReadCommit
* @param mutexTimeout
*/
void setReadCommitProtectionBehaviour(bool protectEveryReadCommit,
uint32_t mutexTimeout = 20);
/**
* @brief The fill_count attribute ensures that the variables
* register in the correct array position and that the maximum
* number of variables is not exceeded.
*/
uint16_t fillCount = 0;
/**
* States of the seet.
*/
enum class States {
STATE_SET_UNINITIALISED, //!< DATA_SET_UNINITIALISED
STATE_SET_WAS_READ //!< DATA_SET_WAS_READ
};
/**
* @brief state manages the internal state of the data set,
* which is important e.g. for the behavior on destruction.
*/
States state = States::STATE_SET_UNINITIALISED;
/**
* @brief This array represents all pool variables registered in this set.
* Child classes can use a static or dynamic container to create
* an array of registered variables and assign the first entry here.
*/
PoolVariableIF** registeredVariables = nullptr;
const size_t maxFillCount = 0;
void setContainer(PoolVariableIF** variablesContainer);
private:
bool protectEveryReadCommitCall = false;
uint32_t mutexTimeout = 20;
ReturnValue_t readVariable(uint16_t count);
void handleAlreadyReadDatasetCommit(uint32_t lockTimeout);
ReturnValue_t handleUnreadDatasetCommit(uint32_t lockTimeout);
};
#endif /* FSFW_DATAPOOL_POOLDATASETBASE_H_ */