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