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TDBStore.h
1/*
2 * Copyright (c) 2018 ARM Limited. All rights reserved.
3 * SPDX-License-Identifier: Apache-2.0
4 * Licensed under the Apache License, Version 2.0 (the License); you may
5 * not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef MBED_TDBSTORE_H
18#define MBED_TDBSTORE_H
19
20#include <stdint.h>
21#include <stdio.h>
22#include "kvstore/KVStore.h"
23#include "blockdevice/BlockDevice.h"
24#include "blockdevice/BufferedBlockDevice.h"
25#include "rtos/Mutex.h"
26#include "mbed_error.h"
27
28namespace mbed {
29
30/**
31* \addtogroup kvstore
32* @{
33*/
34
35/**
36 * Tiny Database Storage (TDBStore) is a lightweight module that stores data on flash storage. It is part of of
37 * the KVStore class family, meaning it supports the get/set interface. It is designed to optimize performance
38 * (speed of access), reduce wearing of the flash and minimize storage overhead. It is also resilient to power
39 * failures.
40 *
41 * TDBStore assumes the underlying block device is fully dedicated to it (starting offset 0). If you want to
42 * dedicate only a part of the device to TDBStore, use a sliced block device, typically with SlicingBlockDevice.
43 */
44
45class TDBStore : public KVStore {
46public:
47
48 static const uint32_t RESERVED_AREA_SIZE = 64;
49
50 /**
51 * @brief Class constructor
52 *
53 * @param[in] bd Underlying block device.
54 */
55 TDBStore(BlockDevice *bd);
56
57 /**
58 * @brief Class destructor
59 */
60 virtual ~TDBStore();
61
62 /**
63 * @brief Initialize TDBStore. If data exists, TDBStore will check the data integrity
64 * on initialize. If the integrity checks fails, the TDBStore will use GC to collect
65 * the available data and clean corrupted and erroneous records.
66 *
67 * @returns MBED_SUCCESS Success.
68 * @returns Negative error code on failure.
69 */
70 virtual int init();
71
72 /**
73 * @brief Deinitialize TDBStore, release and free resources.
74 *
75 * @returns MBED_SUCCESS Success.
76 */
77 virtual int deinit();
78
79
80 /**
81 * @brief Reset TDBStore contents (clear all keys) and reserved data
82 *
83 * @returns MBED_SUCCESS Success.
84 * MBED_ERROR_NOT_READY Not initialized.
85 * MBED_ERROR_READ_FAILED Unable to read from media.
86 * MBED_ERROR_WRITE_FAILED Unable to write to media.
87 */
88 virtual int reset();
89
90 /**
91 * @brief Set one TDBStore item, given key and value.
92 *
93 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
94 * @param[in] buffer Value data buffer.
95 * @param[in] size Value data size.
96 * @param[in] create_flags Flag mask.
97 *
98 * @returns MBED_SUCCESS Success.
99 * MBED_ERROR_NOT_READY Not initialized.
100 * MBED_ERROR_READ_FAILED Unable to read from media.
101 * MBED_ERROR_WRITE_FAILED Unable to write to media.
102 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
103 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
104 * MBED_ERROR_MEDIA_FULL Not enough room on media.
105 * MBED_ERROR_WRITE_PROTECTED Already stored with "write once" flag.
106 */
107 virtual int set(const char *key, const void *buffer, size_t size, uint32_t create_flags);
108
109 /**
110 * @brief Get one TDBStore item by given key.
111 *
112 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
113 * @param[in] buffer Value data buffer.
114 * @param[in] buffer_size Value data buffer size.
115 * @param[out] actual_size Actual read size.
116 * @param[in] offset Offset to read from in data.
117 *
118 * @returns MBED_SUCCESS Success.
119 * MBED_ERROR_NOT_READY Not initialized.
120 * MBED_ERROR_READ_FAILED Unable to read from media.
121 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
122 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
123 * MBED_ERROR_INVALID_DATA_DETECTED Data is corrupt.
124 * MBED_ERROR_ITEM_NOT_FOUND No such key.
125 */
126 virtual int get(const char *key, void *buffer, size_t buffer_size, size_t *actual_size = NULL,
127 size_t offset = 0);
128
129 /**
130 * @brief Get information of a given key. The returned info contains size and flags
131 *
132 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
133 * @param[out] info Returned information structure.
134 *
135 * @returns MBED_SUCCESS Success.
136 * MBED_ERROR_NOT_READY Not initialized.
137 * MBED_ERROR_READ_FAILED Unable to read from media.
138 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
139 * MBED_ERROR_INVALID_DATA_DETECTED Data is corrupt.
140 * MBED_ERROR_ITEM_NOT_FOUND No such key.
141 */
142 virtual int get_info(const char *key, info_t *info);
143
144 /**
145 * @brief Remove a TDBStore item by given key.
146 *
147 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
148 *
149 * @returns MBED_SUCCESS Success.
150 * MBED_ERROR_NOT_READY Not initialized.
151 * MBED_ERROR_READ_FAILED Unable to read from media.
152 * MBED_ERROR_WRITE_FAILED Unable to write to media.
153 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
154 * MBED_ERROR_MEDIA_FULL Not enough room on media.
155 * MBED_ERROR_ITEM_NOT_FOUND No such key.
156 * MBED_ERROR_WRITE_PROTECTED Already stored with "write once" flag.
157 */
158 virtual int remove(const char *key);
159
160
161 /**
162 * @brief Start an incremental TDBStore set sequence. This operation is blocking other operations.
163 * Any get/set/remove/iterator operation will be blocked until set_finalize is called.
164 *
165 * @param[out] handle Returned incremental set handle.
166 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
167 * @param[in] final_data_size Final value data size.
168 * @param[in] create_flags Flag mask.
169 *
170 * @returns MBED_SUCCESS Success.
171 * MBED_ERROR_NOT_READY Not initialized.
172 * MBED_ERROR_READ_FAILED Unable to read from media.
173 * MBED_ERROR_WRITE_FAILED Unable to write to media.
174 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
175 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
176 * MBED_ERROR_MEDIA_FULL Not enough room on media.
177 * MBED_ERROR_WRITE_PROTECTED Already stored with "write once" flag.
178 */
179 virtual int set_start(set_handle_t *handle, const char *key, size_t final_data_size, uint32_t create_flags);
180
181 /**
182 * @brief Add data to incremental TDBStore set sequence. This operation is blocking other operations.
183 * Any get/set/remove operation will be blocked until set_finalize will be called.
184 *
185 * @param[in] handle Incremental set handle.
186 * @param[in] value_data Value data to add.
187 * @param[in] data_size Value data size.
188 *
189 * @returns MBED_SUCCESS Success.
190 * MBED_ERROR_NOT_READY Not initialized.
191 * MBED_ERROR_WRITE_FAILED Unable to write to media.
192 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
193 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
194 */
195 virtual int set_add_data(set_handle_t handle, const void *value_data, size_t data_size);
196
197 /**
198 * @brief Finalize an incremental KVStore set sequence.
199 *
200 * @param[in] handle Incremental set handle.
201 *
202 * @returns MBED_SUCCESS Success.
203 * MBED_ERROR_NOT_READY Not initialized.
204 * MBED_ERROR_WRITE_FAILED Unable to write to media.
205 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
206 */
207 virtual int set_finalize(set_handle_t handle);
208
209 /**
210 * @brief Start an iteration over KVStore keys.
211 * There are no issues with any other operations while iterator is open.
212 *
213 * @param[out] it Returned iterator handle.
214 * @param[in] prefix Key prefix (null for all keys).
215 *
216 * @returns MBED_SUCCESS Success.
217 * MBED_ERROR_NOT_READY Not initialized.
218 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
219 */
220 virtual int iterator_open(iterator_t *it, const char *prefix = NULL);
221
222 /**
223 * @brief Get next key in iteration.
224 * There are no issues with any other operations while iterator is open.
225 *
226 * @param[in] it Iterator handle.
227 * @param[in] key Buffer for returned key.
228 * @param[in] key_size Key buffer size.
229 *
230 * @returns MBED_SUCCESS Success.
231 * MBED_ERROR_NOT_READY Not initialized.
232 * MBED_ERROR_READ_FAILED Unable to read from block device.
233 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
234 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
235 * MBED_ERROR_INVALID_DATA_DETECTED Data is corrupt.
236 * MBED_ERROR_ITEM_NOT_FOUND No more keys found.
237 */
238 virtual int iterator_next(iterator_t it, char *key, size_t key_size);
239
240 /**
241 * @brief Close iteration.
242 *
243 * @param[in] it Iterator handle.
244 *
245 * @returns MBED_SUCCESS Success.
246 * MBED_ERROR_NOT_READY Not initialized.
247 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
248 */
249 virtual int iterator_close(iterator_t it);
250
251 /**
252 * @brief Set data in reserved area, which is a special location for special data, such as ROT.
253 * The data written to reserved area can't be overwritten.
254 *
255 * @param[in] reserved_data Reserved data buffer.
256 * @param[in] reserved_data_buf_size
257 * Reserved data buffer size.
258 *
259 * @returns MBED_SUCCESS Success.
260 * MBED_ERROR_NOT_READY Not initialized.
261 * MBED_ERROR_READ_FAILED Unable to read from media.
262 * MBED_ERROR_WRITE_FAILED Unable to write to media.
263 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
264 * MBED_ERROR_INVALID_SIZE Invalid size given in function arguments.
265 */
266 virtual int reserved_data_set(const void *reserved_data, size_t reserved_data_buf_size);
267
268 /**
269 * @brief Get data from reserved area, which is a special location for special data, such as ROT.
270 *
271 * @param[in] reserved_data Reserved data buffer.
272 * @param[in] reserved_data_buf_size
273 * Reserved data buffer size.
274 * @param[in] actual_data_size Return data size.
275 *
276 * @returns MBED_SUCCESS Success.
277 * MBED_ERROR_NOT_READY Not initialized.
278 * MBED_ERROR_READ_FAILED Unable to read from media.
279 * MBED_ERROR_INVALID_ARGUMENT Invalid argument given in function arguments.
280 * MBED_ERROR_INVALID_DATA_DETECTED Data is corrupt.
281 * MBED_ERROR_ITEM_NOT_FOUND No reserved data was written.
282 */
283 virtual int reserved_data_get(void *reserved_data, size_t reserved_data_buf_size,
284 size_t *actual_data_size = 0);
285
286#if !defined(DOXYGEN_ONLY)
287private:
288
289 typedef struct {
290 uint32_t address;
291 size_t size;
292 } tdbstore_area_data_t;
293
294 static const int _num_areas = 2;
295 static const int _max_open_iterators = 16;
296
297 rtos::Mutex _mutex;
298 rtos::Mutex _inc_set_mutex;
299 void *_ram_table;
300 size_t _max_keys;
301 size_t _num_keys;
302 BlockDevice *_bd;
303 BufferedBlockDevice *_buff_bd;
304 uint32_t _free_space_offset;
305 uint32_t _master_record_offset;
306 uint32_t _master_record_size;
307 bool _is_initialized;
308 int _active_area;
309 uint16_t _active_area_version;
310 size_t _size;
311 tdbstore_area_data_t _area_params[_num_areas];
312 uint32_t _prog_size;
313 uint8_t *_work_buf;
314 size_t _work_buf_size;
315 char *_key_buf;
316 void *_inc_set_handle;
317 void *_iterator_table[_max_open_iterators];
318
319 /**
320 * @brief Read a block from an area.
321 *
322 * @param[in] area Area.
323 * @param[in] offset Offset in area.
324 * @param[in] size Number of bytes to read.
325 * @param[in] buf Output buffer.
326 *
327 * @returns 0 for success, nonzero for failure.
328 */
329 int read_area(uint8_t area, uint32_t offset, uint32_t size, void *buf);
330
331 /**
332 * @brief Write a block to an area.
333 *
334 * @param[in] area Area.
335 * @param[in] offset Offset in area.
336 * @param[in] size Number of bytes to write.
337 * @param[in] buf Input buffer.
338 *
339 * @returns 0 for success, non-zero for failure.
340 */
341 int write_area(uint8_t area, uint32_t offset, uint32_t size, const void *buf);
342
343 /**
344 * @brief Reset an area (erase its start).
345 * This erases master record, but preserves the
346 * reserved area data.
347 *
348 * @param[in] area Area.
349 *
350 * @returns 0 for success, nonzero for failure.
351 */
352 int reset_area(uint8_t area);
353
354 /**
355 * @brief Erase an area.
356 *
357 * @param[in] area Area.
358 * @param[in] offset Offset in area.
359 * @param[in] size Number of bytes to erase.
360 *
361 * @returns 0 for success, nonzero for failure.
362 */
363 int erase_area(uint8_t area, uint32_t offset, uint32_t size);
364
365 /**
366 * @brief Calculate addresses and sizes of areas.
367 */
368 void calc_area_params();
369
370 /**
371 * @brief Read a TDBStore record from a given location.
372 *
373 * @param[in] area Area.
374 * @param[in] offset Offset of record in area.
375 * @param[out] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
376 * @param[out] data_buf Data buffer.
377 * @param[in] data_buf_size Data buffer size.
378 * @param[out] actual_data_size Actual data size.
379 * @param[in] data_offset Offset in data.
380 * @param[in] copy_key Copy key to user buffer.
381 * @param[in] copy_data Copy data to user buffer.
382 * @param[in] check_expected_key Check whether key belongs to this record.
383 * @param[in] calc_hash Calculate hash (on key).
384 * @param[out] hash Calculated hash.
385 * @param[out] flags Record flags.
386 * @param[out] next_offset Offset of next record.
387 *
388 * @returns 0 for success, nonzero for failure.
389 */
390 int read_record(uint8_t area, uint32_t offset, char *key,
391 void *data_buf, uint32_t data_buf_size,
392 uint32_t &actual_data_size, size_t data_offset, bool copy_key,
393 bool copy_data, bool check_expected_key, bool calc_hash,
394 uint32_t &hash, uint32_t &flags, uint32_t &next_offset);
395
396 /**
397 * @brief Write a master record of a given area.
398 *
399 * @param[in] area Area.
400 * @param[in] version Area version.
401 * @param[out] next_offset Offset of next record.
402 *
403 * @returns 0 for success, nonzero for failure.
404 */
405 int write_master_record(uint8_t area, uint16_t version, uint32_t &next_offset);
406
407 /**
408 * @brief Copy a record from one area to the opposite one.
409 *
410 * @param[in] from_area Area to copy record from.
411 * @param[in] from_offset Offset in source area.
412 * @param[in] to_offset Offset in destination area.
413 * @param[out] to_next_offset Offset of next record in destination area.
414 *
415 * @returns 0 for success, nonzero for failure.
416 */
417 int copy_record(uint8_t from_area, uint32_t from_offset, uint32_t to_offset,
418 uint32_t &to_next_offset);
419
420 /**
421 * @brief Garbage collection (compact all records from active area to the standby one).
422 *
423 * @returns 0 for success, nonzero for failure.
424 */
425 int garbage_collection();
426
427 /**
428 * @brief Return record size given key and data size.
429 *
430 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
431 * @param[in] data_size Data size.
432 *
433 * @returns record size.
434 */
435 uint32_t record_size(const char *key, uint32_t data_size);
436
437 /**
438 * @brief Find a record given key
439 *
440 * @param[in] area Area.
441 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
442 * @param[out] offset Offset of record.
443 * @param[out] ram_table_ind Index in RAM table (target one if not found).
444 * @param[out] hash Calculated key hash.
445 *
446 * @returns 0 for success, nonzero for failure.
447 */
448 int find_record(uint8_t area, const char *key, uint32_t &offset,
449 uint32_t &ram_table_ind, uint32_t &hash);
450 /**
451 * @brief Actual logics of get API (also covers all other get APIs).
452 *
453 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
454 * @param[in] copy_data Copy data to user buffer.
455 * @param[in] data_buf Buffer to store data on.
456 * @param[in] data_buf_size Data buffer size (bytes).
457 * @param[out] actual_data_size Actual data size (bytes).
458 * @param[out] flags Flags.
459 *
460 * @returns 0 for success, nonzero for failure.
461 */
462 int do_get(const char *key, bool copy_data,
463 void *data_buf, uint32_t data_buf_size, uint32_t &actual_data_size,
464 uint32_t &flags);
465
466 /**
467 * @brief Actual logics of set API (covers also the remove API).
468 *
469 * @param[in] key Key - must not include '*' '/' '?' ':' ';' '\' '"' '|' ' ' '<' '>' '\'.
470 * @param[in] data_buf Data buffer.
471 * @param[in] data_buf_size Data buffer size (bytes).
472 * @param[in] flags Flags.
473 *
474 * @returns 0 for success, nonzero for failure.
475 */
476 int do_set(const char *key, const void *data_buf, uint32_t data_buf_size, uint32_t flags);
477
478 /**
479 * @brief Build RAM table and update _free_space_offset (scanning all the records in the area).
480 *
481 * @returns 0 for success, nonzero for failure.
482 */
483 int build_ram_table();
484
485 /**
486 * @brief Increment maximum number of keys and reallocate RAM table accordingly.
487 *
488 * @param[out] ram_table Updated RAM table.
489 *
490 * @returns 0 for success, nonzero for failure.
491 */
492 int increment_max_keys(void **ram_table = 0);
493
494 /**
495 * @brief Calculate offset from start of erase unit.
496 *
497 * @param[in] area Area.
498 * @param[in] offset Offset in area.
499 * @param[out] offset_from_start Offset from start of erase unit.
500 * @param[out] dist_to_end Distance to end of erase unit.
501 *
502 * @returns offset in erase unit.
503 */
504 void offset_in_erase_unit(uint8_t area, uint32_t offset, uint32_t &offset_from_start,
505 uint32_t &dist_to_end);
506
507 /**
508 * @brief Before writing a record, check whether you are crossing an erase unit.
509 * If you do, check if it's erased, and erase it if not.
510 *
511 * @param[in] area Area.
512 * @param[in] offset Offset in area.
513 * @param[in] size Write size.
514 * @param[in] force_check Force checking.
515 *
516 * @returns 0 for success, nonzero for failure.
517 */
518 int check_erase_before_write(uint8_t area, uint32_t offset, uint32_t size,
519 bool force_check = false);
520
521 /**
522 * @brief Get data from reserved area - worker function.
523 * This verifies that reserved data on both areas have
524 * correct checksums. If given pointer is not NULL, also
525 * write the reserved data to buffer. If checksums are not
526 * valid, return error code, and don't write anything to any
527 * pointers.
528 *
529 * @param[out] reserved_data Reserved data buffer (NULL to return nothing).
530 * @param[in] reserved_data_buf_size
531 * Reserved data buffer size.
532 * @param[out] actual_data_size If not NULL, return actual data size.
533 * @param[out] copy_trailer If not NULL, copy the trailer content to given buffer.
534 *
535 * @returns 0 on success or a negative error code on failure
536 */
537 int do_reserved_data_get(void *reserved_data, size_t reserved_data_buf_size,
538 size_t *actual_data_size = 0, void *copy_trailer = 0);
539
540 /**
541 * @brief Update all iterators after adding or deleting of keys.
542 *
543 * @param[in] added True if added, false if deleted.
544 * @param[in] ram_table_ind RAM table index.
545 *
546 * @returns none
547 */
548 void update_all_iterators(bool added, uint32_t ram_table_ind);
549
550#endif
551
552};
553/** @}*/
554
555} // namespace mbed
556
557#endif
mbed::BlockDevice
A hardware device capable of writing and reading blocks.
Definition BlockDevice.h:53
mbed::BufferedBlockDevice
Block device which allows minimal read and program sizes (of 1) for the underlying BD using a buffer ...
Definition BufferedBlockDevice.h:39
mbed::KVStore
KVStore class.
Definition KVStore.h:38
mbed::TDBStore
Tiny Database Storage (TDBStore) is a lightweight module that stores data on flash storage.
Definition TDBStore.h:45
mbed::TDBStore::TDBStore
TDBStore(BlockDevice *bd)
Class constructor.
mbed::TDBStore::get_info
virtual int get_info(const char *key, info_t *info)
Get information of a given key.
mbed::TDBStore::iterator_open
virtual int iterator_open(iterator_t *it, const char *prefix=NULL)
Start an iteration over KVStore keys.
mbed::TDBStore::remove
virtual int remove(const char *key)
Remove a TDBStore item by given key.
mbed::TDBStore::iterator_next
virtual int iterator_next(iterator_t it, char *key, size_t key_size)
Get next key in iteration.
mbed::TDBStore::~TDBStore
virtual ~TDBStore()
Class destructor.
mbed::TDBStore::set_finalize
virtual int set_finalize(set_handle_t handle)
Finalize an incremental KVStore set sequence.
mbed::TDBStore::set
virtual int set(const char *key, const void *buffer, size_t size, uint32_t create_flags)
Set one TDBStore item, given key and value.
mbed::TDBStore::iterator_close
virtual int iterator_close(iterator_t it)
Close iteration.
mbed::TDBStore::set_start
virtual int set_start(set_handle_t *handle, const char *key, size_t final_data_size, uint32_t create_flags)
Start an incremental TDBStore set sequence.
mbed::TDBStore::deinit
virtual int deinit()
Deinitialize TDBStore, release and free resources.
mbed::TDBStore::reset
virtual int reset()
Reset TDBStore contents (clear all keys) and reserved data.
mbed::TDBStore::get
virtual int get(const char *key, void *buffer, size_t buffer_size, size_t *actual_size=NULL, size_t offset=0)
Get one TDBStore item by given key.
mbed::TDBStore::reserved_data_get
virtual int reserved_data_get(void *reserved_data, size_t reserved_data_buf_size, size_t *actual_data_size=0)
Get data from reserved area, which is a special location for special data, such as ROT.
mbed::TDBStore::set_add_data
virtual int set_add_data(set_handle_t handle, const void *value_data, size_t data_size)
Add data to incremental TDBStore set sequence.
mbed::TDBStore::init
virtual int init()
Initialize TDBStore.
mbed::TDBStore::reserved_data_set
virtual int reserved_data_set(const void *reserved_data, size_t reserved_data_buf_size)
Set data in reserved area, which is a special location for special data, such as ROT.
rtos::Mutex
The Mutex class is used to synchronize the execution of threads.
Definition Mutex.h:70
mbed::KVStore::info
Holds key information.
Definition KVStore.h:56