lfs.h 26 KB

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  1. /*
  2. * The little filesystem
  3. *
  4. * Copyright (c) 2017, Arm Limited. All rights reserved.
  5. * SPDX-License-Identifier: BSD-3-Clause
  6. */
  7. #ifndef LFS_H
  8. #define LFS_H
  9. #include <stdint.h>
  10. #include <stdbool.h>
  11. #include "lfs_util.h"
  12. #ifdef __cplusplus
  13. extern "C"
  14. {
  15. #endif
  16. /// Version info ///
  17. // Software library version
  18. // Major (top-nibble), incremented on backwards incompatible changes
  19. // Minor (bottom-nibble), incremented on feature additions
  20. #define LFS_VERSION 0x00020002
  21. #define LFS_VERSION_MAJOR (0xffff & (LFS_VERSION >> 16))
  22. #define LFS_VERSION_MINOR (0xffff & (LFS_VERSION >> 0))
  23. // Version of On-disk data structures
  24. // Major (top-nibble), incremented on backwards incompatible changes
  25. // Minor (bottom-nibble), incremented on feature additions
  26. #define LFS_DISK_VERSION 0x00020000
  27. #define LFS_DISK_VERSION_MAJOR (0xffff & (LFS_DISK_VERSION >> 16))
  28. #define LFS_DISK_VERSION_MINOR (0xffff & (LFS_DISK_VERSION >> 0))
  29. /// Definitions ///
  30. // Type definitions
  31. typedef uint32_t lfs_size_t;
  32. typedef uint32_t lfs_off_t;
  33. typedef int32_t lfs_ssize_t;
  34. typedef int32_t lfs_soff_t;
  35. typedef uint32_t lfs_block_t;
  36. // Maximum name size in bytes, may be redefined to reduce the size of the
  37. // info struct. Limited to <= 1022. Stored in superblock and must be
  38. // respected by other littlefs drivers.
  39. #ifndef LFS_NAME_MAX
  40. #define LFS_NAME_MAX 255
  41. #endif
  42. // Maximum size of a file in bytes, may be redefined to limit to support other
  43. // drivers. Limited on disk to <= 4294967296. However, above 2147483647 the
  44. // functions _lfs_file_seek, _lfs_file_size, and _lfs_file_tell will return
  45. // incorrect values due to using signed integers. Stored in superblock and
  46. // must be respected by other littlefs drivers.
  47. #ifndef LFS_FILE_MAX
  48. #define LFS_FILE_MAX 2147483647
  49. #endif
  50. // Maximum size of custom attributes in bytes, may be redefined, but there is
  51. // no real benefit to using a smaller LFS_ATTR_MAX. Limited to <= 1022.
  52. #ifndef LFS_ATTR_MAX
  53. #define LFS_ATTR_MAX 1022
  54. #endif
  55. // Possible error codes, these are negative to allow
  56. // valid positive return values
  57. enum lfs_error {
  58. LFS_ERR_OK = 0, // No error
  59. LFS_ERR_IO = -5, // Error during device operation
  60. LFS_ERR_CORRUPT = -84, // Corrupted
  61. LFS_ERR_NOENT = -2, // No directory entry
  62. LFS_ERR_EXIST = -17, // Entry already exists
  63. LFS_ERR_NOTDIR = -20, // Entry is not a dir
  64. LFS_ERR_ISDIR = -21, // Entry is a dir
  65. LFS_ERR_NOTEMPTY = -39, // Dir is not empty
  66. LFS_ERR_BADF = -9, // Bad file number
  67. LFS_ERR_FBIG = -27, // File too large
  68. LFS_ERR_INVAL = -22, // Invalid parameter
  69. LFS_ERR_NOSPC = -28, // No space left on device
  70. LFS_ERR_NOMEM = -12, // No more memory available
  71. LFS_ERR_NOATTR = -61, // No data/attr available
  72. LFS_ERR_NAMETOOLONG = -36, // File name too long
  73. #if LFS_THREAD_SAFE
  74. LFS_ERR_LOCK = -23, // Failed to aquire lock
  75. #endif
  76. };
  77. // File types
  78. enum lfs_type {
  79. // file types
  80. LFS_TYPE_REG = 0x001,
  81. LFS_TYPE_DIR = 0x002,
  82. // internally used types
  83. LFS_TYPE_SPLICE = 0x400,
  84. LFS_TYPE_NAME = 0x000,
  85. LFS_TYPE_STRUCT = 0x200,
  86. LFS_TYPE_USERATTR = 0x300,
  87. LFS_TYPE_FROM = 0x100,
  88. LFS_TYPE_TAIL = 0x600,
  89. LFS_TYPE_GLOBALS = 0x700,
  90. LFS_TYPE_CRC = 0x500,
  91. // internally used type specializations
  92. LFS_TYPE_CREATE = 0x401,
  93. LFS_TYPE_DELETE = 0x4ff,
  94. LFS_TYPE_SUPERBLOCK = 0x0ff,
  95. LFS_TYPE_DIRSTRUCT = 0x200,
  96. LFS_TYPE_CTZSTRUCT = 0x202,
  97. LFS_TYPE_INLINESTRUCT = 0x201,
  98. LFS_TYPE_SOFTTAIL = 0x600,
  99. LFS_TYPE_HARDTAIL = 0x601,
  100. LFS_TYPE_MOVESTATE = 0x7ff,
  101. // internal chip sources
  102. LFS_FROM_NOOP = 0x000,
  103. LFS_FROM_MOVE = 0x101,
  104. LFS_FROM_USERATTRS = 0x102,
  105. };
  106. // File open flags
  107. enum lfs_open_flags {
  108. // open flags
  109. LFS_O_RDONLY = 1, // Open a file as read only
  110. LFS_O_WRONLY = 2, // Open a file as write only
  111. LFS_O_RDWR = 3, // Open a file as read and write
  112. LFS_O_CREAT = 0x0100, // Create a file if it does not exist
  113. LFS_O_EXCL = 0x0200, // Fail if a file already exists
  114. LFS_O_TRUNC = 0x0400, // Truncate the existing file to zero size
  115. LFS_O_APPEND = 0x0800, // Move to end of file on every write
  116. // internally used flags
  117. LFS_F_DIRTY = 0x010000, // File does not match storage
  118. LFS_F_WRITING = 0x020000, // File has been written since last flush
  119. LFS_F_READING = 0x040000, // File has been read since last flush
  120. LFS_F_ERRED = 0x080000, // An error occured during write
  121. LFS_F_INLINE = 0x100000, // Currently inlined in directory entry
  122. LFS_F_OPENED = 0x200000, // File has been opened
  123. };
  124. // File seek flags
  125. enum lfs_whence_flags {
  126. LFS_SEEK_SET = 0, // Seek relative to an absolute position
  127. LFS_SEEK_CUR = 1, // Seek relative to the current file position
  128. LFS_SEEK_END = 2, // Seek relative to the end of the file
  129. };
  130. // Configuration provided during initialization of the littlefs
  131. struct lfs_config {
  132. // Opaque user provided context that can be used to pass
  133. // information to the block device operations
  134. void *context;
  135. // Read a region in a block. Negative error codes are propogated
  136. // to the user.
  137. int (*read)(const struct lfs_config *c, lfs_block_t block,
  138. lfs_off_t off, void *buffer, lfs_size_t size);
  139. // Program a region in a block. The block must have previously
  140. // been erased. Negative error codes are propogated to the user.
  141. // May return LFS_ERR_CORRUPT if the block should be considered bad.
  142. int (*prog)(const struct lfs_config *c, lfs_block_t block,
  143. lfs_off_t off, const void *buffer, lfs_size_t size);
  144. // Erase a block. A block must be erased before being programmed.
  145. // The state of an erased block is undefined. Negative error codes
  146. // are propogated to the user.
  147. // May return LFS_ERR_CORRUPT if the block should be considered bad.
  148. int (*erase)(const struct lfs_config *c, lfs_block_t block);
  149. // Sync the state of the underlying block device. Negative error codes
  150. // are propogated to the user.
  151. int (*sync)(const struct lfs_config *c);
  152. #if LFS_THREAD_SAFE
  153. // Lock the underlying block device. Negative error codes
  154. // are propogated to the user.
  155. int (*lock)(const struct lfs_config *c);
  156. // Unlock the underlying block device. Negative error codes
  157. // are propogated to the user.
  158. int (*unlock)(const struct lfs_config *c);
  159. #endif
  160. // Minimum size of a block read. All read operations will be a
  161. // multiple of this value.
  162. lfs_size_t read_size;
  163. // Minimum size of a block program. All program operations will be a
  164. // multiple of this value.
  165. lfs_size_t prog_size;
  166. // Size of an erasable block. This does not impact ram consumption and
  167. // may be larger than the physical erase size. However, non-inlined files
  168. // take up at minimum one block. Must be a multiple of the read
  169. // and program sizes.
  170. lfs_size_t block_size;
  171. // Number of erasable blocks on the device.
  172. lfs_size_t block_count;
  173. // Number of erase cycles before littlefs evicts metadata logs and moves
  174. // the metadata to another block. Suggested values are in the
  175. // range 100-1000, with large values having better performance at the cost
  176. // of less consistent wear distribution.
  177. //
  178. // Set to -1 to disable block-level wear-leveling.
  179. int32_t block_cycles;
  180. // Size of block caches. Each cache buffers a portion of a block in RAM.
  181. // The littlefs needs a read cache, a program cache, and one additional
  182. // cache per file. Larger caches can improve performance by storing more
  183. // data and reducing the number of disk accesses. Must be a multiple of
  184. // the read and program sizes, and a factor of the block size.
  185. lfs_size_t cache_size;
  186. // Size of the lookahead buffer in bytes. A larger lookahead buffer
  187. // increases the number of blocks found during an allocation pass. The
  188. // lookahead buffer is stored as a compact bitmap, so each byte of RAM
  189. // can track 8 blocks. Must be a multiple of 8.
  190. lfs_size_t lookahead_size;
  191. // Optional statically allocated read buffer. Must be cache_size.
  192. // By default lfs_malloc is used to allocate this buffer.
  193. void *read_buffer;
  194. // Optional statically allocated program buffer. Must be cache_size.
  195. // By default lfs_malloc is used to allocate this buffer.
  196. void *prog_buffer;
  197. // Optional statically allocated lookahead buffer. Must be lookahead_size
  198. // and aligned to a 32-bit boundary. By default lfs_malloc is used to
  199. // allocate this buffer.
  200. void *lookahead_buffer;
  201. // Optional upper limit on length of file names in bytes. No downside for
  202. // larger names except the size of the info struct which is controlled by
  203. // the LFS_NAME_MAX define. Defaults to LFS_NAME_MAX when zero. Stored in
  204. // superblock and must be respected by other littlefs drivers.
  205. lfs_size_t name_max;
  206. // Optional upper limit on files in bytes. No downside for larger files
  207. // but must be <= LFS_FILE_MAX. Defaults to LFS_FILE_MAX when zero. Stored
  208. // in superblock and must be respected by other littlefs drivers.
  209. lfs_size_t file_max;
  210. // Optional upper limit on custom attributes in bytes. No downside for
  211. // larger attributes size but must be <= LFS_ATTR_MAX. Defaults to
  212. // LFS_ATTR_MAX when zero.
  213. lfs_size_t attr_max;
  214. };
  215. // File info structure
  216. struct lfs_info {
  217. // Type of the file, either LFS_TYPE_REG or LFS_TYPE_DIR
  218. uint8_t type;
  219. // Size of the file, only valid for REG files. Limited to 32-bits.
  220. lfs_size_t size;
  221. // Name of the file stored as a null-terminated string. Limited to
  222. // LFS_NAME_MAX+1, which can be changed by redefining LFS_NAME_MAX to
  223. // reduce RAM. LFS_NAME_MAX is stored in superblock and must be
  224. // respected by other littlefs drivers.
  225. char name[LFS_NAME_MAX+1];
  226. };
  227. // Custom attribute structure, used to describe custom attributes
  228. // committed atomically during file writes.
  229. struct lfs_attr {
  230. // 8-bit type of attribute, provided by user and used to
  231. // identify the attribute
  232. uint8_t type;
  233. // Pointer to buffer containing the attribute
  234. void *buffer;
  235. // Size of attribute in bytes, limited to LFS_ATTR_MAX
  236. lfs_size_t size;
  237. };
  238. // Optional configuration provided during lfs_file_opencfg
  239. struct lfs_file_config {
  240. // Optional statically allocated file buffer. Must be cache_size.
  241. // By default lfs_malloc is used to allocate this buffer.
  242. void *buffer;
  243. // Optional list of custom attributes related to the file. If the file
  244. // is opened with read access, these attributes will be read from disk
  245. // during the open call. If the file is opened with write access, the
  246. // attributes will be written to disk every file sync or close. This
  247. // write occurs atomically with update to the file's contents.
  248. //
  249. // Custom attributes are uniquely identified by an 8-bit type and limited
  250. // to LFS_ATTR_MAX bytes. When read, if the stored attribute is smaller
  251. // than the buffer, it will be padded with zeros. If the stored attribute
  252. // is larger, then it will be silently truncated. If the attribute is not
  253. // found, it will be created implicitly.
  254. struct lfs_attr *attrs;
  255. // Number of custom attributes in the list
  256. lfs_size_t attr_count;
  257. };
  258. /// internal littlefs data structures ///
  259. typedef struct lfs_cache {
  260. lfs_block_t block;
  261. lfs_off_t off;
  262. lfs_size_t size;
  263. uint8_t *buffer;
  264. } lfs_cache_t;
  265. typedef struct lfs_mdir {
  266. lfs_block_t pair[2];
  267. uint32_t rev;
  268. lfs_off_t off;
  269. uint32_t etag;
  270. uint16_t count;
  271. bool erased;
  272. bool split;
  273. lfs_block_t tail[2];
  274. } lfs_mdir_t;
  275. // littlefs directory type
  276. typedef struct lfs_dir {
  277. struct lfs_dir *next;
  278. uint16_t id;
  279. uint8_t type;
  280. lfs_mdir_t m;
  281. lfs_off_t pos;
  282. lfs_block_t head[2];
  283. } lfs_dir_t;
  284. // littlefs file type
  285. typedef struct lfs_file {
  286. struct lfs_file *next;
  287. uint16_t id;
  288. uint8_t type;
  289. lfs_mdir_t m;
  290. struct lfs_ctz {
  291. lfs_block_t head;
  292. lfs_size_t size;
  293. } ctz;
  294. uint32_t flags;
  295. lfs_off_t pos;
  296. lfs_block_t block;
  297. lfs_off_t off;
  298. lfs_cache_t cache;
  299. const struct lfs_file_config *cfg;
  300. } lfs_file_t;
  301. typedef struct lfs_superblock {
  302. uint32_t version;
  303. lfs_size_t block_size;
  304. lfs_size_t block_count;
  305. lfs_size_t name_max;
  306. lfs_size_t file_max;
  307. lfs_size_t attr_max;
  308. } lfs_superblock_t;
  309. typedef struct lfs_gstate {
  310. uint32_t tag;
  311. lfs_block_t pair[2];
  312. } lfs_gstate_t;
  313. // The littlefs filesystem type
  314. typedef struct lfs {
  315. lfs_cache_t rcache;
  316. lfs_cache_t pcache;
  317. lfs_block_t root[2];
  318. struct lfs_mlist {
  319. struct lfs_mlist *next;
  320. uint16_t id;
  321. uint8_t type;
  322. lfs_mdir_t m;
  323. } *mlist;
  324. uint32_t seed;
  325. lfs_gstate_t gstate;
  326. lfs_gstate_t gdisk;
  327. lfs_gstate_t gdelta;
  328. struct lfs_free {
  329. lfs_block_t off;
  330. lfs_block_t size;
  331. lfs_block_t i;
  332. lfs_block_t ack;
  333. uint32_t *buffer;
  334. } free;
  335. const struct lfs_config *cfg;
  336. lfs_size_t name_max;
  337. lfs_size_t file_max;
  338. lfs_size_t attr_max;
  339. #ifdef LFS_MIGRATE
  340. struct lfs1 *lfs1;
  341. #endif
  342. } lfs_t;
  343. /// Filesystem functions ///
  344. // Format a block device with the littlefs
  345. //
  346. // Requires a littlefs object and config struct. This clobbers the littlefs
  347. // object, and does not leave the filesystem mounted. The config struct must
  348. // be zeroed for defaults and backwards compatibility.
  349. //
  350. // Returns a negative error code on failure.
  351. int _lfs_format(lfs_t *lfs, const struct lfs_config *config);
  352. // Mounts a littlefs
  353. //
  354. // Requires a littlefs object and config struct. Multiple filesystems
  355. // may be mounted simultaneously with multiple littlefs objects. Both
  356. // lfs and config must be allocated while mounted. The config struct must
  357. // be zeroed for defaults and backwards compatibility.
  358. //
  359. // Returns a negative error code on failure.
  360. int _lfs_mount(lfs_t *lfs, const struct lfs_config *config);
  361. // Unmounts a littlefs
  362. //
  363. // Does nothing besides releasing any allocated resources.
  364. // Returns a negative error code on failure.
  365. int _lfs_unmount(lfs_t *lfs);
  366. /// General operations ///
  367. // Removes a file or directory
  368. //
  369. // If removing a directory, the directory must be empty.
  370. // Returns a negative error code on failure.
  371. int _lfs_remove(lfs_t *lfs, const char *path);
  372. // Rename or move a file or directory
  373. //
  374. // If the destination exists, it must match the source in type.
  375. // If the destination is a directory, the directory must be empty.
  376. //
  377. // Returns a negative error code on failure.
  378. int _lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath);
  379. // Find info about a file or directory
  380. //
  381. // Fills out the info structure, based on the specified file or directory.
  382. // Returns a negative error code on failure.
  383. int _lfs_stat(lfs_t *lfs, const char *path, struct lfs_info *info);
  384. // Get a custom attribute
  385. //
  386. // Custom attributes are uniquely identified by an 8-bit type and limited
  387. // to LFS_ATTR_MAX bytes. When read, if the stored attribute is smaller than
  388. // the buffer, it will be padded with zeros. If the stored attribute is larger,
  389. // then it will be silently truncated. If no attribute is found, the error
  390. // LFS_ERR_NOATTR is returned and the buffer is filled with zeros.
  391. //
  392. // Returns the size of the attribute, or a negative error code on failure.
  393. // Note, the returned size is the size of the attribute on disk, irrespective
  394. // of the size of the buffer. This can be used to dynamically allocate a buffer
  395. // or check for existance.
  396. lfs_ssize_t _lfs_getattr(lfs_t *lfs, const char *path,
  397. uint8_t type, void *buffer, lfs_size_t size);
  398. // Set custom attributes
  399. //
  400. // Custom attributes are uniquely identified by an 8-bit type and limited
  401. // to LFS_ATTR_MAX bytes. If an attribute is not found, it will be
  402. // implicitly created.
  403. //
  404. // Returns a negative error code on failure.
  405. int _lfs_setattr(lfs_t *lfs, const char *path,
  406. uint8_t type, const void *buffer, lfs_size_t size);
  407. // Removes a custom attribute
  408. //
  409. // If an attribute is not found, nothing happens.
  410. //
  411. // Returns a negative error code on failure.
  412. int _lfs_removeattr(lfs_t *lfs, const char *path, uint8_t type);
  413. /// File operations ///
  414. // Open a file
  415. //
  416. // The mode that the file is opened in is determined by the flags, which
  417. // are values from the enum lfs_open_flags that are bitwise-ored together.
  418. //
  419. // Returns a negative error code on failure.
  420. int _lfs_file_open(lfs_t *lfs, lfs_file_t *file,
  421. const char *path, int flags);
  422. // Open a file with extra configuration
  423. //
  424. // The mode that the file is opened in is determined by the flags, which
  425. // are values from the enum lfs_open_flags that are bitwise-ored together.
  426. //
  427. // The config struct provides additional config options per file as described
  428. // above. The config struct must be allocated while the file is open, and the
  429. // config struct must be zeroed for defaults and backwards compatibility.
  430. //
  431. // Returns a negative error code on failure.
  432. int _lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file,
  433. const char *path, int flags,
  434. const struct lfs_file_config *config);
  435. // Close a file
  436. //
  437. // Any pending writes are written out to storage as though
  438. // sync had been called and releases any allocated resources.
  439. //
  440. // Returns a negative error code on failure.
  441. int _lfs_file_close(lfs_t *lfs, lfs_file_t *file);
  442. // Synchronize a file on storage
  443. //
  444. // Any pending writes are written out to storage.
  445. // Returns a negative error code on failure.
  446. int _lfs_file_sync(lfs_t *lfs, lfs_file_t *file);
  447. // Read data from file
  448. //
  449. // Takes a buffer and size indicating where to store the read data.
  450. // Returns the number of bytes read, or a negative error code on failure.
  451. lfs_ssize_t _lfs_file_read(lfs_t *lfs, lfs_file_t *file,
  452. void *buffer, lfs_size_t size);
  453. // Write data to file
  454. //
  455. // Takes a buffer and size indicating the data to write. The file will not
  456. // actually be updated on the storage until either sync or close is called.
  457. //
  458. // Returns the number of bytes written, or a negative error code on failure.
  459. lfs_ssize_t _lfs_file_write(lfs_t *lfs, lfs_file_t *file,
  460. const void *buffer, lfs_size_t size);
  461. // Change the position of the file
  462. //
  463. // The change in position is determined by the offset and whence flag.
  464. // Returns the new position of the file, or a negative error code on failure.
  465. lfs_soff_t _lfs_file_seek(lfs_t *lfs, lfs_file_t *file,
  466. lfs_soff_t off, int whence);
  467. // Truncates the size of the file to the specified size
  468. //
  469. // Returns a negative error code on failure.
  470. int _lfs_file_truncate(lfs_t *lfs, lfs_file_t *file, lfs_off_t size);
  471. // Return the position of the file
  472. //
  473. // Equivalent to _lfs_file_seek(lfs, file, 0, LFS_SEEK_CUR)
  474. // Returns the position of the file, or a negative error code on failure.
  475. lfs_soff_t _lfs_file_tell(lfs_t *lfs, lfs_file_t *file);
  476. // Change the position of the file to the beginning of the file
  477. //
  478. // Equivalent to _lfs_file_seek(lfs, file, 0, LFS_SEEK_SET)
  479. // Returns a negative error code on failure.
  480. int _lfs_file_rewind(lfs_t *lfs, lfs_file_t *file);
  481. // Return the size of the file
  482. //
  483. // Similar to _lfs_file_seek(lfs, file, 0, LFS_SEEK_END)
  484. // Returns the size of the file, or a negative error code on failure.
  485. lfs_soff_t _lfs_file_size(lfs_t *lfs, lfs_file_t *file);
  486. /// Directory operations ///
  487. // Create a directory
  488. //
  489. // Returns a negative error code on failure.
  490. int _lfs_mkdir(lfs_t *lfs, const char *path);
  491. // Open a directory
  492. //
  493. // Once open a directory can be used with read to iterate over files.
  494. // Returns a negative error code on failure.
  495. int _lfs_dir_open(lfs_t *lfs, lfs_dir_t *dir, const char *path);
  496. // Close a directory
  497. //
  498. // Releases any allocated resources.
  499. // Returns a negative error code on failure.
  500. int _lfs_dir_close(lfs_t *lfs, lfs_dir_t *dir);
  501. // Read an entry in the directory
  502. //
  503. // Fills out the info structure, based on the specified file or directory.
  504. // Returns a positive value on success, 0 at the end of directory,
  505. // or a negative error code on failure.
  506. int _lfs_dir_read(lfs_t *lfs, lfs_dir_t *dir, struct lfs_info *info);
  507. // Change the position of the directory
  508. //
  509. // The new off must be a value previous returned from tell and specifies
  510. // an absolute offset in the directory seek.
  511. //
  512. // Returns a negative error code on failure.
  513. int _lfs_dir_seek(lfs_t *lfs, lfs_dir_t *dir, lfs_off_t off);
  514. // Return the position of the directory
  515. //
  516. // The returned offset is only meant to be consumed by seek and may not make
  517. // sense, but does indicate the current position in the directory iteration.
  518. //
  519. // Returns the position of the directory, or a negative error code on failure.
  520. lfs_soff_t _lfs_dir_tell(lfs_t *lfs, lfs_dir_t *dir);
  521. // Change the position of the directory to the beginning of the directory
  522. //
  523. // Returns a negative error code on failure.
  524. int _lfs_dir_rewind(lfs_t *lfs, lfs_dir_t *dir);
  525. /// Filesystem-level filesystem operations
  526. // Finds the current size of the filesystem
  527. //
  528. // Note: Result is best effort. If files share COW structures, the returned
  529. // size may be larger than the filesystem actually is.
  530. //
  531. // Returns the number of allocated blocks, or a negative error code on failure.
  532. lfs_ssize_t _lfs_fs_size(lfs_t *lfs);
  533. // Traverse through all blocks in use by the filesystem
  534. //
  535. // The provided callback will be called with each block address that is
  536. // currently in use by the filesystem. This can be used to determine which
  537. // blocks are in use or how much of the storage is available.
  538. //
  539. // Returns a negative error code on failure.
  540. int _lfs_fs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data);
  541. #ifdef LFS_MIGRATE
  542. // Attempts to migrate a previous version of littlefs
  543. //
  544. // Behaves similarly to the _lfs_format function. Attempts to mount
  545. // the previous version of littlefs and update the filesystem so it can be
  546. // mounted with the current version of littlefs.
  547. //
  548. // Requires a littlefs object and config struct. This clobbers the littlefs
  549. // object, and does not leave the filesystem mounted. The config struct must
  550. // be zeroed for defaults and backwards compatibility.
  551. //
  552. // Returns a negative error code on failure.
  553. int _lfs_migrate(lfs_t *lfs, const struct lfs_config *cfg);
  554. #endif
  555. #if LFS_THREAD_SAFE
  556. int _ts_lfs_format(lfs_t *lfs, const struct lfs_config *config);
  557. int _ts_lfs_mount(lfs_t *lfs, const struct lfs_config *config);
  558. int _ts_lfs_unmount(lfs_t *lfs);
  559. int _ts_lfs_remove(lfs_t *lfs, const char *path);
  560. int _ts_lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath);
  561. int _ts_lfs_stat(lfs_t *lfs, const char *path, struct lfs_info *info);
  562. lfs_ssize_t _ts_lfs_getattr(lfs_t *lfs, const char *path, uint8_t type, void *buffer, lfs_size_t size);
  563. int _ts_lfs_setattr(lfs_t *lfs, const char *path, uint8_t type, const void *buffer, lfs_size_t size);
  564. int _ts_lfs_removeattr(lfs_t *lfs, const char *path, uint8_t type);
  565. int _ts_lfs_file_open(lfs_t *lfs, lfs_file_t *file, const char *path, int flags);
  566. int _ts_lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file, const char *path, int flags, const struct lfs_file_config *config);
  567. int _ts_lfs_file_close(lfs_t *lfs, lfs_file_t *file);
  568. int _ts_lfs_file_sync(lfs_t *lfs, lfs_file_t *file);
  569. lfs_ssize_t _ts_lfs_file_read(lfs_t *lfs, lfs_file_t *file, void *buffer, lfs_size_t size);
  570. lfs_ssize_t _ts_lfs_file_write(lfs_t *lfs, lfs_file_t *file, const void *buffer, lfs_size_t size);
  571. lfs_soff_t _ts_lfs_file_seek(lfs_t *lfs, lfs_file_t *file, lfs_soff_t off, int whence);
  572. int _ts_lfs_file_truncate(lfs_t *lfs, lfs_file_t *file, lfs_off_t size);
  573. lfs_soff_t _ts_lfs_file_tell(lfs_t *lfs, lfs_file_t *file);
  574. int _ts_lfs_file_rewind(lfs_t *lfs, lfs_file_t *file);
  575. lfs_soff_t _ts_lfs_file_size(lfs_t *lfs, lfs_file_t *file);
  576. int _ts_lfs_mkdir(lfs_t *lfs, const char *path);
  577. int _ts_lfs_dir_open(lfs_t *lfs, lfs_dir_t *dir, const char *path);
  578. int _ts_lfs_dir_close(lfs_t *lfs, lfs_dir_t *dir);
  579. int _ts_lfs_dir_read(lfs_t *lfs, lfs_dir_t *dir, struct lfs_info *info);
  580. int _ts_lfs_dir_seek(lfs_t *lfs, lfs_dir_t *dir, lfs_off_t off);
  581. lfs_soff_t _ts_lfs_dir_tell(lfs_t *lfs, lfs_dir_t *dir);
  582. int _ts_lfs_dir_rewind(lfs_t *lfs, lfs_dir_t *dir);
  583. lfs_ssize_t _ts_lfs_fs_size(lfs_t *lfs);
  584. int _ts_lfs_fs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data);
  585. int _ts_lfs_migrate(lfs_t *lfs, const struct lfs_config *cfg);
  586. #define lfs_format _ts_lfs_format
  587. #define lfs_mount _ts_lfs_mount
  588. #define lfs_unmount _ts_lfs_unmount
  589. #define lfs_remove _ts_lfs_remove
  590. #define lfs_rename _ts_lfs_rename
  591. #define lfs_stat _ts_lfs_stat
  592. #define lfs_getattr _ts_lfs_getattr
  593. #define lfs_setattr _ts_lfs_setattr
  594. #define lfs_removeattr _ts_lfs_removeattr
  595. #define lfs_file_open _ts_lfs_file_open
  596. #define lfs_file_opencfg _ts_lfs_file_opencfg
  597. #define lfs_file_close _ts_lfs_file_close
  598. #define lfs_file_sync _ts_lfs_file_sync
  599. #define lfs_file_read _ts_lfs_file_read
  600. #define lfs_file_write _ts_lfs_file_write
  601. #define lfs_file_seek _ts_lfs_file_seek
  602. #define lfs_file_truncate _ts_lfs_file_truncate
  603. #define lfs_file_tell _ts_lfs_file_tell
  604. #define lfs_file_rewind _ts_lfs_file_rewind
  605. #define lfs_file_size _ts_lfs_file_size
  606. #define lfs_mkdir _ts_lfs_mkdir
  607. #define lfs_dir_open _ts_lfs_dir_open
  608. #define lfs_dir_close _ts_lfs_dir_close
  609. #define lfs_dir_read _ts_lfs_dir_read
  610. #define lfs_dir_seek _ts_lfs_dir_seek
  611. #define lfs_dir_tell _ts_lfs_dir_tell
  612. #define lfs_dir_rewind _ts_lfs_dir_rewind
  613. #define lfs_fs_size _ts_lfs_fs_size
  614. #define lfs_fs_traverse _ts_lfs_fs_traverse
  615. #define lfs_migrate _ts_lfs_migrate
  616. #else
  617. #define lfs_format _lfs_format
  618. #define lfs_mount _lfs_mount
  619. #define lfs_unmount _lfs_unmount
  620. #define lfs_remove _lfs_remove
  621. #define lfs_rename _lfs_rename
  622. #define lfs_stat _lfs_stat
  623. #define lfs_getattr _lfs_getattr
  624. #define lfs_setattr _lfs_setattr
  625. #define lfs_removeattr _lfs_removeattr
  626. #define lfs_file_open _lfs_file_open
  627. #define lfs_file_opencfg _lfs_file_opencfg
  628. #define lfs_file_close _lfs_file_close
  629. #define lfs_file_sync _lfs_file_sync
  630. #define lfs_file_read _lfs_file_read
  631. #define lfs_file_write _lfs_file_write
  632. #define lfs_file_seek _lfs_file_seek
  633. #define lfs_file_truncate _lfs_file_truncate
  634. #define lfs_file_tell _lfs_file_tell
  635. #define lfs_file_rewind _lfs_file_rewind
  636. #define lfs_file_size _lfs_file_size
  637. #define lfs_mkdir _lfs_mkdir
  638. #define lfs_dir_open _lfs_dir_open
  639. #define lfs_dir_close _lfs_dir_close
  640. #define lfs_dir_read _lfs_dir_read
  641. #define lfs_dir_seek _lfs_dir_seek
  642. #define lfs_dir_tell _lfs_dir_tell
  643. #define lfs_dir_rewind _lfs_dir_rewind
  644. #define lfs_fs_size _lfs_fs_size
  645. #define lfs_fs_traverse _lfs_fs_traverse
  646. #define lfs_migrate _lfs_migrate
  647. #endif
  648. #ifdef __cplusplus
  649. } /* extern "C" */
  650. #endif
  651. #endif