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diff --git a/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/fds/fds.h b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/fds/fds.h new file mode 100644 index 0000000..09d1eea --- /dev/null +++ b/thirdparty/nRF5_SDK_15.0.0_a53641a/components/libraries/fds/fds.h @@ -0,0 +1,700 @@ +/** + * Copyright (c) 2015 - 2018, Nordic Semiconductor ASA + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form, except as embedded into a Nordic + * Semiconductor ASA integrated circuit in a product or a software update for + * such product, must reproduce the above copyright notice, this list of + * conditions and the following disclaimer in the documentation and/or other + * materials provided with the distribution. + * + * 3. Neither the name of Nordic Semiconductor ASA nor the names of its + * contributors may be used to endorse or promote products derived from this + * software without specific prior written permission. + * + * 4. This software, with or without modification, must only be used with a + * Nordic Semiconductor ASA integrated circuit. + * + * 5. Any software provided in binary form under this license must not be reverse + * engineered, decompiled, modified and/or disassembled. + * + * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS + * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE + * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ +#ifndef FDS_H__ +#define FDS_H__ + +/** + * @defgroup fds Flash Data Storage + * @ingroup app_common + * @{ + * + * @brief Flash Data Storage (FDS). + * + * @details Flash Data Storage is a minimalistic, record-oriented file system for the on-chip + * flash. Files are stored as a collection of records of variable length. FDS supports + * synchronous read operations and asynchronous write operations (write, update, + * and delete). FDS can be used from multiple threads. + */ + +#include <stdint.h> +#include <stdbool.h> +#include "sdk_errors.h" +#include "app_util_platform.h" + +#ifdef __cplusplus +extern "C" { +#endif + + +/**@brief Invalid file ID. + * + * This value must not be used as a file ID by the application. + */ +#define FDS_FILE_ID_INVALID (0xFFFF) + + +/**@brief Record key for deleted records. + * + * This key is used to flag a record as "dirty", which means that it should be removed during + * the next garbage collection. This value must not be used as a record key by the application. + */ +#define FDS_RECORD_KEY_DIRTY (0x0000) + + +/**@brief FDS return values. + */ +enum +{ + FDS_SUCCESS = NRF_SUCCESS, //!< The operation completed successfully. + FDS_ERR_OPERATION_TIMEOUT, //!< Error. The operation timed out. + FDS_ERR_NOT_INITIALIZED, //!< Error. The module has not been initialized. + FDS_ERR_UNALIGNED_ADDR, //!< Error. The input data is not aligned to a word boundary. + FDS_ERR_INVALID_ARG, //!< Error. The parameter contains invalid data. + FDS_ERR_NULL_ARG, //!< Error. The parameter is NULL. + FDS_ERR_NO_OPEN_RECORDS, //!< Error. The record is not open, so it cannot be closed. + FDS_ERR_NO_SPACE_IN_FLASH, //!< Error. There is no space in flash memory. + FDS_ERR_NO_SPACE_IN_QUEUES, //!< Error. There is no space in the internal queues. + FDS_ERR_RECORD_TOO_LARGE, //!< Error. The record exceeds the maximum allowed size. + FDS_ERR_NOT_FOUND, //!< Error. The record was not found. + FDS_ERR_NO_PAGES, //!< Error. No flash pages are available. + FDS_ERR_USER_LIMIT_REACHED, //!< Error. The maximum number of users has been reached. + FDS_ERR_CRC_CHECK_FAILED, //!< Error. The CRC check failed. + FDS_ERR_BUSY, //!< Error. The underlying flash subsystem was busy. + FDS_ERR_INTERNAL, //!< Error. An internal error occurred. +}; + + +/**@brief The record metadata as stored in flash. + * @warning Do not edit or reorder the fields in this structure. + */ +typedef struct +{ + uint16_t record_key; //!< The record key. + uint16_t length_words; //!< The length of the record data (in 4-byte words). + uint16_t file_id; //!< The ID of the file that the record belongs to. + uint16_t crc16; //!< CRC16-CCITT check value. + /* The CRC is calculated over the entire record as stored in flash, + * including the record metadata except the CRC field itself. + */ + uint32_t record_id; //!< The unique record ID (32 bits). +} fds_header_t; + + +/**@brief The record descriptor structure that is used to manipulate records. + * + * This structure is used by the FDS module. You must provide the descriptor to the module when + * you manipulate existing records. However, you should never modify it or use any of its fields. + * + * @note Never reuse the same descriptor for different records. + */ +typedef struct +{ + uint32_t record_id; //!< The unique record ID. + uint32_t const * p_record; //!< The last known location of the record in flash. + uint16_t gc_run_count; //!< Number of times garbage collection has been run. + bool record_is_open; //!< Whether the record is currently open. +} fds_record_desc_t; + + +/**@brief Structure that can be used to read the contents of a record stored in flash. + * + * This structure does not reflect the physical layout of a record in flash, but it points + * to the locations where the record header (metadata) and the record data are stored. + */ +typedef struct +{ + fds_header_t const * p_header; //!< Location of the record header in flash. + void const * p_data; //!< Location of the record data in flash. +} fds_flash_record_t; + + +/**@brief A record to be written to flash. */ +typedef struct +{ + uint16_t file_id; //!< The ID of the file that the record belongs to. + uint16_t key; //!< The record key. + struct + { + void const * p_data; + uint32_t length_words; + } data; +} fds_record_t; + + +/**@brief A token to a reserved space in flash, created by @ref fds_reserve. + * + * This token can be used to write the record in the reserved space (@ref fds_record_write_reserved) + * or to cancel the reservation (@ref fds_reserve_cancel). + */ +typedef struct +{ + uint16_t page; //!< The logical ID of the page where space was reserved. + uint16_t length_words; //!< The amount of space reserved (in 4-byte words). +} fds_reserve_token_t; + + +/**@brief A token to keep information about the progress of @ref fds_record_find, + * @ref fds_record_find_by_key, and @ref fds_record_find_in_file. + * + * @note Always zero-initialize the token before using it for the first time. + * @note Never reuse the same token to search for different records. + */ +typedef struct +{ + uint32_t const * p_addr; + uint16_t page; +} fds_find_token_t; + + +/**@brief FDS event IDs. + */ +typedef enum +{ + FDS_EVT_INIT, //!< Event for @ref fds_init. + FDS_EVT_WRITE, //!< Event for @ref fds_record_write and @ref fds_record_write_reserved. + FDS_EVT_UPDATE, //!< Event for @ref fds_record_update. + FDS_EVT_DEL_RECORD, //!< Event for @ref fds_record_delete. + FDS_EVT_DEL_FILE, //!< Event for @ref fds_file_delete. + FDS_EVT_GC //!< Event for @ref fds_gc. +} fds_evt_id_t; + + +ANON_UNIONS_ENABLE; + +/**@brief An FDS event. */ +typedef struct +{ + fds_evt_id_t id; //!< The event ID. See @ref fds_evt_id_t. + ret_code_t result; //!< The result of the operation related to this event. + union + { + struct + { + uint32_t record_id; + uint16_t file_id; + uint16_t record_key; + bool is_record_updated; + } write; //!< Information for @ref FDS_EVT_WRITE and @ref FDS_EVT_UPDATE events. + struct + { + uint32_t record_id; + uint16_t file_id; + uint16_t record_key; + } del; //!< Information for @ref FDS_EVT_DEL_RECORD and @ref FDS_EVT_DEL_FILE events. + }; +} fds_evt_t; + +ANON_UNIONS_DISABLE; + + +/**@brief File system statistics. */ +typedef struct +{ + uint16_t pages_available; //!< The number of pages available. + uint16_t open_records; //!< The number of open records. + uint16_t valid_records; //!< The number of valid records. + uint16_t dirty_records; //!< The number of deleted ("dirty") records. + uint16_t words_reserved; //!< The number of words reserved by @ref fds_reserve(). + + /**@brief The number of words written to flash, including those reserved for future writes. */ + uint16_t words_used; + + /**@brief The largest number of free contiguous words in the file system. + * + * This number indicates the largest record that can be stored by FDS. + * It takes into account all reservations for future writes. + */ + uint16_t largest_contig; + + /**@brief The largest number of words that can be reclaimed by garbage collection. + * + * The actual amount of space freed by garbage collection might be less than this value if + * records are open while garbage collection is run. + */ + uint16_t freeable_words; + + /**@brief Filesystem corruption has been detected. + * + * One or more corrupted records were detected. FDS will heal the filesystem automatically + * next time garbage collection is run, but some data may be lost. + * + * @note: This flag is unrelated to CRC failures. + */ + bool corruption; +} fds_stat_t; + + +/**@brief FDS event handler function prototype. + * + * @param p_evt The event. + */ +typedef void (*fds_cb_t)(fds_evt_t const * p_evt); + + +/**@brief Function for registering an FDS event handler. + * + * The maximum amount of handlers that can be registered can be configured by changing the value + * of @ref FDS_MAX_USERS in fds_config.h. + * + * @param[in] cb The event handler function. + * + * @retval FDS_SUCCESS If the event handler was registered successfully. + * @retval FDS_ERR_USER_LIMIT_REACHED If the maximum number of registered callbacks is reached. + */ +ret_code_t fds_register(fds_cb_t cb); + + +/**@brief Function for initializing the module. + * + * This function initializes the module and installs the file system (unless it is installed + * already). + * + * This function is asynchronous. Completion is reported through an event. Make sure to call + * @ref fds_register before calling @ref fds_init so that you receive the completion event. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NO_PAGES If there is no space available in flash memory to install the + * file system. + */ +ret_code_t fds_init(void); + + +/**@brief Function for writing a record to flash. + * + * There are no restrictions on the file ID and the record key, except that the record key must be + * different from @ref FDS_RECORD_KEY_DIRTY and the file ID must be different from + * @ref FDS_FILE_ID_INVALID. In particular, no restrictions are made regarding the uniqueness of + * the file ID or the record key. All records with the same file ID are grouped into one file. + * If no file with the specified ID exists, it is created. There can be multiple records with the + * same record key in a file. + * + * Some modules need exclusive use of certain file IDs and record keys. + * See @ref lib_fds_functionality_keys for details. + * + * Record data can consist of multiple chunks. The data must be aligned to a 4 byte boundary, and + * because it is not buffered internally, it must be kept in memory until the callback for the + * operation has been received. The length of the data must not exceed @ref FDS_VIRTUAL_PAGE_SIZE + * words minus 14 bytes. + * + * This function is asynchronous. Completion is reported through an event that is sent to + * the registered event handler function. + * + * @param[out] p_desc The descriptor of the record that was written. Pass NULL if you do not + * need the descriptor. + * @param[in] p_record The record to be written to flash. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_record is NULL. + * @retval FDS_ERR_INVALID_ARG If the file ID or the record key is invalid. + * @retval FDS_ERR_UNALIGNED_ADDR If the record data is not aligned to a 4 byte boundary. + * @retval FDS_ERR_RECORD_TOO_LARGE If the record data exceeds the maximum length. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full or there are more record + * chunks than can be buffered. + * @retval FDS_ERR_NO_SPACE_IN_FLASH If there is not enough free space in flash to store the + * record. + */ +ret_code_t fds_record_write(fds_record_desc_t * p_desc, + fds_record_t const * p_record); + + +/**@brief Function for reserving space in flash. + * + * This function can be used to reserve space in flash memory. To write a record into the reserved + * space, use @ref fds_record_write_reserved. Alternatively, use @ref fds_reserve_cancel to cancel + * a reservation. + * + * Note that this function does not write any data to flash. + * + * @param[out] p_token A token that can be used to write a record in the reserved space or + * cancel the reservation. + * @param[in] length_words The length of the record data (in 4-byte words). + * + * @retval FDS_SUCCESS If the flash space was reserved successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_token is NULL instead of a valid token address. + * @retval FDS_ERR_RECORD_TOO_LARGE If the record length exceeds the maximum length. + * @retval FDS_ERR_NO_SPACE_IN_FLASH If there is not enough free space in flash to store the + * record. + */ +ret_code_t fds_reserve(fds_reserve_token_t * p_token, uint16_t length_words); + + +/**@brief Function for canceling an @ref fds_reserve operation. + * + * @param[in] p_token The token that identifies the reservation, produced by @ref fds_reserve. + * + * @retval FDS_SUCCESS If the reservation was canceled. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_token is NULL instead of a valid token address. + * @retval FDS_ERR_INVALID_ARG If @p p_token contains invalid data. + */ +ret_code_t fds_reserve_cancel(fds_reserve_token_t * p_token); + + +/**@brief Function for writing a record to a space in flash that was reserved using + * @ref fds_reserve. + * + * There are no restrictions on the file ID and the record key, except that the record key must be + * different from @ref FDS_RECORD_KEY_DIRTY and the file ID must be different from + * @ref FDS_FILE_ID_INVALID. In particular, no restrictions are made regarding the uniqueness of + * the file ID or the record key. All records with the same file ID are grouped into one file. + * If no file with the specified ID exists, it is created. There can be multiple records with the + * same record key in a file. + * + * Record data can consist of multiple chunks. The data must be aligned to a 4 byte boundary, and + * because it is not buffered internally, it must be kept in memory until the callback for the + * operation has been received. The length of the data must not exceed @ref FDS_VIRTUAL_PAGE_SIZE + * words minus 14 bytes. + * + * This function is asynchronous. Completion is reported through an event that is sent to the + * registered event handler function. + * + * @note + * This function behaves similarly to @ref fds_record_write, with the exception that it never + * fails with the error @ref FDS_ERR_NO_SPACE_IN_FLASH. + * + * @param[out] p_desc The descriptor of the record that was written. Pass NULL if you do not + * need the descriptor. + * @param[in] p_record The record to be written to flash. + * @param[in] p_token The token that identifies the space reserved in flash. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_token is NULL instead of a valid token address. + * @retval FDS_ERR_INVALID_ARG If the file ID or the record key is invalid. + * @retval FDS_ERR_UNALIGNED_ADDR If the record data is not aligned to a 4 byte boundary. + * @retval FDS_ERR_RECORD_TOO_LARGE If the record data exceeds the maximum length. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full or there are more record + * chunks than can be buffered. + */ +ret_code_t fds_record_write_reserved(fds_record_desc_t * p_desc, + fds_record_t const * p_record, + fds_reserve_token_t const * p_token); + + +/**@brief Function for deleting a record. + * + * Deleted records cannot be located using @ref fds_record_find, @ref fds_record_find_by_key, or + * @ref fds_record_find_in_file. Additionally, they can no longer be opened using + * @ref fds_record_open. + * + * Note that deleting a record does not free the space it occupies in flash memory. + * To reclaim flash space used by deleted records, call @ref fds_gc to run garbage collection. + * + * This function is asynchronous. Completion is reported through an event that is sent to the + * registered event handler function. + * + * @param[in] p_desc The descriptor of the record that should be deleted. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If the specified record descriptor @p p_desc is NULL. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full. + */ +ret_code_t fds_record_delete(fds_record_desc_t * p_desc); + + +/**@brief Function for deleting all records in a file. + * + * This function deletes a file, including all its records. Deleted records cannot be located + * using @ref fds_record_find, @ref fds_record_find_by_key, or @ref fds_record_find_in_file. + * Additionally, they can no longer be opened using @ref fds_record_open. + * + * Note that deleting records does not free the space they occupy in flash memory. + * To reclaim flash space used by deleted records, call @ref fds_gc to run garbage collection. + * + * This function is asynchronous. Completion is reported through an event that is sent to the + * registered event handler function. + * + * @param[in] file_id The ID of the file to be deleted. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_INVALID_ARG If the specified @p file_id is invalid. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full. + */ +ret_code_t fds_file_delete(uint16_t file_id); + + +/**@brief Function for updating a record. + * + * Updating a record first writes a new record (@p p_record) to flash and then deletes the + * old record (identified by @p p_desc). + * + * There are no restrictions on the file ID and the record key, except that the record key must be + * different from @ref FDS_RECORD_KEY_DIRTY and the file ID must be different from + * @ref FDS_FILE_ID_INVALID. In particular, no restrictions are made regarding the uniqueness of + * the file ID or the record key. All records with the same file ID are grouped into one file. + * If no file with the specified ID exists, it is created. There can be multiple records with the + * same record key in a file. + * + * Record data can consist of multiple chunks. The data must be aligned to a 4 byte boundary, and + * because it is not buffered internally, it must be kept in memory until the callback for the + * operation has been received. The length of the data must not exceed @ref FDS_VIRTUAL_PAGE_SIZE + * words minus 14 bytes. + * + * This function is asynchronous. Completion is reported through an event that is sent to the + * registered event handler function. + * + * @param[in, out] p_desc The descriptor of the record to update. When the function + * returns with FDS_SUCCESS, this parameter contains the + * descriptor of the newly written record. + * @param[in] p_record The updated record to be written to flash. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_INVALID_ARG If the file ID or the record key is invalid. + * @retval FDS_ERR_UNALIGNED_ADDR If the record data is not aligned to a 4 byte boundary. + * @retval FDS_ERR_RECORD_TOO_LARGE If the record data exceeds the maximum length. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full or there are more record + * chunks than can be buffered. + * @retval FDS_ERR_NO_SPACE_IN_FLASH If there is not enough free space in flash to store the + * updated record. + */ +ret_code_t fds_record_update(fds_record_desc_t * p_desc, + fds_record_t const * p_record); + + +/**@brief Function for iterating through all records in flash. + * + * To search for the next record, call the function again and supply the same @ref fds_find_token_t + * structure to resume searching from the last record that was found. + * + * Note that the order with which records are iterated is not defined. + * + * @param[out] p_desc The descriptor of the record that was found. + * @param[out] p_token A token containing information about the progress of the operation. + * + * @retval FDS_SUCCESS If a record was found. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_token is NULL. + * @retval FDS_ERR_NOT_FOUND If no matching record was found. + */ +ret_code_t fds_record_iterate(fds_record_desc_t * p_desc, + fds_find_token_t * p_token); + + +/**@brief Function for searching for records with a given record key in a file. + * + * This function finds the first record in a file that has the given record key. To search for the + * next record with the same key in the file, call the function again and supply the same + * @ref fds_find_token_t structure to resume searching from the last record that was found. + * + * @param[in] file_id The file ID. + * @param[in] record_key The record key. + * @param[out] p_desc The descriptor of the record that was found. + * @param[out] p_token A token containing information about the progress of the operation. + * + * @retval FDS_SUCCESS If a record was found. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_token is NULL. + * @retval FDS_ERR_NOT_FOUND If no matching record was found. + */ +ret_code_t fds_record_find(uint16_t file_id, + uint16_t record_key, + fds_record_desc_t * p_desc, + fds_find_token_t * p_token); + + +/**@brief Function for searching for records with a given record key. + * + * This function finds the first record with a given record key, independent of the file it + * belongs to. To search for the next record with the same key, call the function again and supply + * the same @ref fds_find_token_t structure to resume searching from the last record that was found. + * + * @param[in] record_key The record key. + * @param[out] p_desc The descriptor of the record that was found. + * @param[out] p_token A token containing information about the progress of the operation. + * + * @retval FDS_SUCCESS If a record was found. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_token is NULL. + * @retval FDS_ERR_NOT_FOUND If no record with the given key was found. + */ +ret_code_t fds_record_find_by_key(uint16_t record_key, + fds_record_desc_t * p_desc, + fds_find_token_t * p_token); + + +/**@brief Function for searching for any record in a file. + * + * This function finds the first record in a file, independent of its record key. + * To search for the next record in the same file, call the function again and supply the same + * @ref fds_find_token_t structure to resume searching from the last record that was found. + * + * @param[in] file_id The file ID. + * @param[out] p_desc The descriptor of the record that was found. + * @param[out] p_token A token containing information about the progress of the operation. + * + * @retval FDS_SUCCESS If a record was found. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_token is NULL. + * @retval FDS_ERR_NOT_FOUND If no matching record was found. + */ +ret_code_t fds_record_find_in_file(uint16_t file_id, + fds_record_desc_t * p_desc, + fds_find_token_t * p_token); + + +/**@brief Function for opening a record for reading. + * + * This function opens a record that is stored in flash, so that it can be read. The function + * initializes an @ref fds_flash_record_t structure, which can be used to access the record data as + * well as its associated metadata. The pointers provided in the @ref fds_flash_record_t structure + * are pointers to flash memory. + * + * Opening a record with @ref fds_record_open prevents garbage collection to run on the virtual + * flash page in which record is stored, so that the contents of the memory pointed by fields in + * @ref fds_flash_record_t are guaranteed to remain unmodified as long as the record is kept open. + * + * When you are done reading a record, call @ref fds_record_close to close it. Garbage collection + * can then reclaim space on the virtual page where the record is stored. Note that you must + * provide the same descriptor for @ref fds_record_close as you did for this function. + * + * @param[in] p_desc The descriptor of the record to open. + * @param[out] p_flash_record The record, as stored in flash. + * + * @retval FDS_SUCCESS If the record was opened successfully. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_flash_record is NULL. + * @retval FDS_ERR_NOT_FOUND If the record was not found. It might have been deleted, or + * it might not have been written yet. + * @retval FDS_ERR_CRC_CHECK_FAILED If the CRC check for the record failed. + */ +ret_code_t fds_record_open(fds_record_desc_t * p_desc, + fds_flash_record_t * p_flash_record); + + +/**@brief Function for closing a record. + * + * Closing a record allows garbage collection to run on the virtual page in which the record is + * stored (if no other records remain open on that page). The descriptor passed as an argument + * must be the same as the one used to open the record using @ref fds_record_open. + * + * Note that closing a record does not invalidate its descriptor. You can still supply the + * descriptor to all functions that accept a record descriptor as a parameter. + * + * @param[in] p_desc The descriptor of the record to close. + * + * @retval FDS_SUCCESS If the record was closed successfully. + * @retval FDS_ERR_NULL_ARG If @p p_desc is NULL. + * @retval FDS_ERR_NO_OPEN_RECORDS If the record is not open. + * @retval FDS_ERR_NOT_FOUND If the record could not be found. + */ +ret_code_t fds_record_close(fds_record_desc_t * p_desc); + + +/**@brief Function for running garbage collection. + * + * Garbage collection reclaims the flash space that is occupied by records that have been deleted, + * or that failed to be completely written due to, for example, a power loss. + * + * This function is asynchronous. Completion is reported through an event that is sent to the + * registered event handler function. + * + * @retval FDS_SUCCESS If the operation was queued successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NO_SPACE_IN_QUEUES If the operation queue is full. + */ +ret_code_t fds_gc(void); + + +/**@brief Function for obtaining a descriptor from a record ID. + * + * This function can be used to reconstruct a descriptor from a record ID, like the one that is + * passed to the callback function. + * + * @note + * This function does not check whether a record with the given record ID exists. + * If a non-existing record ID is supplied, the resulting descriptor is invalid and will cause + * other functions to fail when it is supplied as parameter. + * + * @param[out] p_desc The descriptor of the record with the given record ID. + * @param[in] record_id The record ID for which a descriptor should be returned. + * + * @retval FDS_SUCCESS If a descriptor was returned. + * @retval FDS_ERR_NULL_ARG If @p p_desc is NULL. + */ +ret_code_t fds_descriptor_from_rec_id(fds_record_desc_t * p_desc, + uint32_t record_id); + + +/**@brief Function for obtaining a record ID from a record descriptor. + * + * This function can be used to extract a record ID from a descriptor. For example, you could use + * it in the callback function to compare the record ID of an event to the record IDs of the + * records for which you have a descriptor. + * + * @warning + * This function does not check whether the record descriptor is valid. If the descriptor is not + * initialized or has been tampered with, the resulting record ID might be invalid. + * + * @param[in] p_desc The descriptor from which the record ID should be extracted. + * @param[out] p_record_id The record ID that is contained in the given descriptor. + * + * @retval FDS_SUCCESS If a record ID was returned. + * @retval FDS_ERR_NULL_ARG If @p p_desc or @p p_record_id is NULL. + */ +ret_code_t fds_record_id_from_desc(fds_record_desc_t const * p_desc, + uint32_t * p_record_id); + + +/**@brief Function for retrieving file system statistics. + * + * This function retrieves file system statistics, such as the number of open records, the space + * that can be reclaimed by garbage collection, and others. + * + * @param[out] p_stat File system statistics. + * + * @retval FDS_SUCCESS If the statistics were returned successfully. + * @retval FDS_ERR_NOT_INITIALIZED If the module is not initialized. + * @retval FDS_ERR_NULL_ARG If @p p_stat is NULL. + */ +ret_code_t fds_stat(fds_stat_t * p_stat); + + +/** @} */ + + +#ifdef __cplusplus +} +#endif + +#endif // FDS_H__ |