fsfw/storagemanager/LocalPool.h
2020-10-15 13:43:23 +02:00

250 lines
9.4 KiB
C++

#ifndef FSFW_STORAGEMANAGER_LOCALPOOL_H_
#define FSFW_STORAGEMANAGER_LOCALPOOL_H_
#include "StorageManagerIF.h"
#include "../objectmanager/SystemObject.h"
#include "../objectmanager/ObjectManagerIF.h"
#include "../serviceinterface/ServiceInterfaceStream.h"
#include "../internalError/InternalErrorReporterIF.h"
#include "../storagemanager/StorageAccessor.h"
#include <vector>
#include <set>
#include <utility>
#include <limits>
/**
* @brief The LocalPool class provides an intermediate data storage with
* a fixed pool size policy.
* @details
* The class implements the StorageManagerIF interface. While the total number
* of pools is fixed, the element sizes in one pool and the number of pool
* elements per pool are set on construction. The full amount of memory is
* allocated on construction.
* The overhead is 4 byte per pool element to store the size information of
* each stored element. To maintain an "empty" information, the pool size is
* limited to 0xFFFF-1 bytes.
* It is possible to store empty packets in the pool.
* The local pool is NOT thread-safe.
*/
class LocalPool: public SystemObject, public StorageManagerIF {
public:
using pool_elem_size_t = size_type;
using n_pool_elem_t = uint16_t;
using LocalPoolCfgPair = std::pair<n_pool_elem_t, pool_elem_size_t>;
// The configuration needs to be provided with the pool sizes ascending
// but the number of pool elements as the first value is more intuitive.
// Therefore, a custom comparator was provided.
struct LocalPoolConfigCmp
{
bool operator ()(const LocalPoolCfgPair &a,
const LocalPoolCfgPair &b) const
{
if(a.second < b.second) {
return true;
}
else if(a.second > b.second) {
return false;
}
else {
if(a.first < b.first) {
return true;
}
else {
return false;
}
}
}
};
using LocalPoolConfig = std::multiset<LocalPoolCfgPair, LocalPoolConfigCmp>;
/**
* @brief This definition generally sets the number of
* different sized pools. It is derived from the number of pairs
* inside the LocalPoolConfig set on object creation.
* @details
* This must be less than the maximum number of pools (currently 0xff).
*/
const max_pools_t NUMBER_OF_POOLS;
/**
* @brief This is the default constructor for a pool manager instance.
* @details
* The pool is configured by passing a set of pairs into the constructor.
* The first value of that pair determines the number of one elements on
* the respective page of the pool while the second value determines how
* many elements with that size are created on that page.
* All regions are to zero on start up.
* @param setObjectId The object identifier to be set. This allows for
* multiple instances of LocalPool in the system.
* @param poolConfig
* This is a set of pairs to configure the number of pages in the pool,
* the size of an element on a page, the number of elements on a page
* and the total size of the pool at once while also implicitely
* sorting the pairs in the right order.
* @param registered
* Determines whether the pool is registered in the object manager or not.
* @param spillsToHigherPools A variable to determine whether
* higher n pools are used if the store is full.
*/
LocalPool(object_id_t setObjectId, const LocalPoolConfig& poolConfig,
bool registered = false, bool spillsToHigherPools = false);
void setToSpillToHigherPools(bool enable);
/**
* @brief In the LocalPool's destructor all allocated memory is freed.
*/
virtual ~LocalPool(void);
/**
* Documentation: See StorageManagerIF.h
*/
ReturnValue_t addData(store_address_t* storeId, const uint8_t * data,
size_t size, bool ignoreFault = false) override;
ReturnValue_t getFreeElement(store_address_t* storeId,const size_t size,
uint8_t** pData, bool ignoreFault = false) override;
ConstAccessorPair getData(store_address_t storeId) override;
ReturnValue_t getData(store_address_t storeId,
ConstStorageAccessor& constAccessor) override;
ReturnValue_t getData(store_address_t storeId,
const uint8_t** packet_ptr, size_t * size) override;
AccessorPair modifyData(store_address_t storeId) override;
ReturnValue_t modifyData(store_address_t storeId,
StorageAccessor& storeAccessor) override;
ReturnValue_t modifyData(store_address_t storeId, uint8_t** packet_ptr,
size_t * size) override;
virtual ReturnValue_t deleteData(store_address_t storeId) override;
virtual ReturnValue_t deleteData(uint8_t* ptr, size_t size,
store_address_t* storeId = nullptr) override;
/**
* Get the total size of allocated memory for pool data.
* There is an additional overhead of the sizes of elements which will
* be assigned to additionalSize
* @return
*/
size_t getTotalSize(size_t* additionalSize) override;
/**
* Get the fill count of the pool. Each character inside the provided
* buffer will be assigned to a rounded percentage fill count for each
* page. The last written byte (at the index bytesWritten - 1)
* will contain the total fill count of the pool as a mean of the
* percentages of single pages.
* @param buffer
* @param maxSize
*/
void getFillCount(uint8_t* buffer, uint8_t* bytesWritten) override;
void clearStore() override;
void clearPage(max_pools_t pageIndex) override;
ReturnValue_t initialize() override;
protected:
/**
* With this helper method, a free element of @c size is reserved.
* @param size The minimum packet size that shall be reserved.
* @param[out] address Storage ID of the reserved data.
* @return - #RETURN_OK on success,
* - the return codes of #getPoolIndex or #findEmpty otherwise.
*/
virtual ReturnValue_t reserveSpace(const size_t size,
store_address_t* address, bool ignoreFault);
private:
/**
* Indicates that this element is free.
* This value limits the maximum size of a pool.
* Change to larger data type if increase is required.
*/
static const size_type STORAGE_FREE = std::numeric_limits<size_type>::max();
/**
* @brief In this array, the element sizes of each pool is stored.
* @details The sizes are maintained for internal pool management. The sizes
* must be set in ascending order on construction.
*/
std::vector<size_type> elementSizes =
std::vector<size_type>(NUMBER_OF_POOLS);
/**
* @brief n_elements stores the number of elements per pool.
* @details These numbers are maintained for internal pool management.
*/
std::vector<uint16_t> numberOfElements =
std::vector<uint16_t>(NUMBER_OF_POOLS);
/**
* @brief store represents the actual memory pool.
* @details It is an array of pointers to memory, which was allocated with
* a @c new call on construction.
*/
std::vector<std::vector<uint8_t>> store =
std::vector<std::vector<uint8_t>>(NUMBER_OF_POOLS);
/**
* @brief The size_list attribute stores the size values of every pool element.
* @details As the number of elements is determined on construction, the size list
* is also dynamically allocated there.
*/
std::vector<std::vector<size_type>> sizeLists =
std::vector<std::vector<size_type>>(NUMBER_OF_POOLS);
//! A variable to determine whether higher n pools are used if
//! the store is full.
bool spillsToHigherPools = false;
/**
* @brief This method safely stores the given data in the given packet_id.
* @details It also sets the size in size_list. The method does not perform
* any range checks, these are done in advance.
* @param packet_id The storage identifier in which the data shall be stored.
* @param data The data to be stored.
* @param size The size of the data to be stored.
*/
void write(store_address_t packetId, const uint8_t* data, size_t size);
/**
* @brief A helper method to read the element size of a certain pool.
* @param pool_index The pool in which to look.
* @return Returns the size of an element or 0.
*/
size_type getPageSize(max_pools_t poolIndex);
/**
* @brief This helper method looks up a fitting pool for a given size.
* @details The pools are looked up in ascending order, so the first that
* fits is used.
* @param packet_size The size of the data to be stored.
* @param[out] poolIndex The fitting pool index found.
* @return - @c RETURN_OK on success,
* - @c DATA_TOO_LARGE otherwise.
*/
ReturnValue_t getPoolIndex(size_t packetSize, uint16_t* poolIndex,
uint16_t startAtIndex = 0);
/**
* @brief This helper method calculates the true array position in store
* of a given packet id.
* @details The method does not perform any range checks, these are done in
* advance.
* @param packet_id The packet id to look up.
* @return Returns the position of the data in store.
*/
size_type getRawPosition(store_address_t storeId);
/**
* @brief This is a helper method to find an empty element in a given pool.
* @details The method searches size_list for the first empty element, so
* duration grows with the fill level of the pool.
* @param pool_index The pool in which the search is performed.
* @param[out] element The first found element in the pool.
* @return - #RETURN_OK on success,
* - #DATA_STORAGE_FULL if the store is full
*/
ReturnValue_t findEmpty(n_pool_elem_t poolIndex, uint16_t* element);
InternalErrorReporterIF *internalErrorReporter = nullptr;
};
#endif /* FSFW_STORAGEMANAGER_LOCALPOOL_H_ */