fsfw/datapool/PoolEntry.h
2020-08-13 20:53:35 +02:00

131 lines
4.2 KiB
C++

#ifndef FRAMEWORK_DATAPOOL_POOLENTRY_H_
#define FRAMEWORK_DATAPOOL_POOLENTRY_H_
#include "PoolEntryIF.h"
#include <initializer_list>
#include <type_traits>
#include <cstddef>
/**
* @brief This is a small helper class that defines a single data pool entry.
* @details
* The helper is used to store all information together with the data as a
* single data pool entry. The content's type is defined by the template
* argument.
*
* It is prepared for use with plain old data types, but may be
* extended to complex types if necessary. It can be initialized with a
* certain value, size and validity flag.
*
* It holds a pointer to the real data and offers methods to access this data
* and to acquire additional information (such as validity and array/byte size).
* It is NOT intended to be used outside DataPool implementations as it performs
* dynamic memory allocation.
*
* @ingroup data_pool
*/
template <typename T>
class PoolEntry : public PoolEntryIF {
public:
static_assert(not std::is_same<T, bool>::value,
"Do not use boolean for the PoolEntry type, use uint8_t "
"instead! The ECSS standard defines a boolean as a one bit "
"field. Therefore it is preferred to store a boolean as an "
"uint8_t");
/**
* @brief In the classe's constructor, space is allocated on the heap and
* potential init values are copied to that space.
* @details
* Not passing any arguments will initialize an non-array pool entry
* (setLength = 1) with an initial invalid state.
* Please note that if an initializer list is passed, the correct
* corresponding length should be passed too, otherwise a zero
* initialization will be performed with the given setLength.
* @param initValue
* Initializer list with values to initialize with, for example {0,0} to
* initialize the two entries to zero.
* @param setLength
* Defines the array length of this entry. Should be equal to the
* intializer list length.
* @param setValid
* Sets the initialization flag. It is invalid by default.
*/
PoolEntry(std::initializer_list<T> initValue = {}, uint8_t setLength = 1,
bool setValid = false);
/**
* @brief In the classe's constructor, space is allocated on the heap and
* potential init values are copied to that space.
* @param initValue
* A pointer to the single value or array that holds the init value.
* With the default value (nullptr), the entry is initalized with all 0.
* @param setLength
* Defines the array length of this entry.
* @param setValid
* Sets the initialization flag. It is invalid by default.
*/
PoolEntry(T* initValue, uint8_t setLength = 1, bool setValid = false);
//! Explicitely deleted copy ctor, copying is not allowed!
PoolEntry(const PoolEntry&) = delete;
//! Explicitely deleted copy assignment, copying is not allowed!
PoolEntry& operator=(const PoolEntry&) = delete;
/**
* @brief The allocated memory for the variable is freed
* in the destructor.
* @details
* As the data pool is global, this dtor is only called on program exit.
* PoolEntries shall never be copied, as a copy might delete the variable
* on the heap.
*/
~PoolEntry();
/**
* @brief This is the address pointing to the allocated memory.
*/
T* address;
/**
* @brief This attribute stores the length information.
*/
uint8_t length;
/**
* @brief Here, the validity information for a variable is stored.
* Every entry (single variable or vector) has one valid flag.
*/
uint8_t valid;
/**
* @brief getSize returns the array size of the entry.
* @details A single parameter has size 1.
*/
uint8_t getSize();
/**
* @brief This operation returns the size in bytes.
* @details The size is calculated by sizeof(type) * array_size.
*/
uint16_t getByteSize();
/**
* @brief This operation returns a the address pointer casted to void*.
*/
void* getRawData();
/**
* @brief This method allows to set the valid information
* of the pool entry.
*/
void setValid( bool isValid );
/**
* @brief This method allows to get the valid information
* of the pool entry.
*/
bool getValid();
/**
* @brief This is a debug method that prints all values and the valid
* information to the screen. It prints all array entries in a row.
*/
void print();
Type getType();
};
#endif /* POOLENTRY_H_ */