diff options
author | Clyne Sullivan <tullivan99@gmail.com> | 2019-02-28 17:04:22 -0500 |
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committer | Clyne Sullivan <tullivan99@gmail.com> | 2019-02-28 17:04:22 -0500 |
commit | d6869d1ec4bd24cd2c3eafa534f0849b25ec5607 (patch) | |
tree | 79e54ed27b39c31864895535d11399708d5a45c0 /arduino/libraries/FileSystem/src/littlefs/lfs.h | |
parent | 614ee97bf3a2270c413527a7f35c54cbecd9e601 (diff) |
added basic code
Diffstat (limited to 'arduino/libraries/FileSystem/src/littlefs/lfs.h')
-rwxr-xr-x | arduino/libraries/FileSystem/src/littlefs/lfs.h | 494 |
1 files changed, 494 insertions, 0 deletions
diff --git a/arduino/libraries/FileSystem/src/littlefs/lfs.h b/arduino/libraries/FileSystem/src/littlefs/lfs.h new file mode 100755 index 0000000..7dd3604 --- /dev/null +++ b/arduino/libraries/FileSystem/src/littlefs/lfs.h @@ -0,0 +1,494 @@ +/* + * The little filesystem + * + * Copyright (c) 2017, Arm Limited. All rights reserved. + * SPDX-License-Identifier: BSD-3-Clause + */ +#ifndef LFS_H +#define LFS_H + +#include <stdint.h> +#include <stdbool.h> + +#ifdef __cplusplus +extern "C" +{ +#endif + + +/// Version info /// + +// Software library version +// Major (top-nibble), incremented on backwards incompatible changes +// Minor (bottom-nibble), incremented on feature additions +#define LFS_VERSION 0x00010006 +#define LFS_VERSION_MAJOR (0xffff & (LFS_VERSION >> 16)) +#define LFS_VERSION_MINOR (0xffff & (LFS_VERSION >> 0)) + +// Version of On-disk data structures +// Major (top-nibble), incremented on backwards incompatible changes +// Minor (bottom-nibble), incremented on feature additions +#define LFS_DISK_VERSION 0x00010001 +#define LFS_DISK_VERSION_MAJOR (0xffff & (LFS_DISK_VERSION >> 16)) +#define LFS_DISK_VERSION_MINOR (0xffff & (LFS_DISK_VERSION >> 0)) + + +/// Definitions /// + +// Type definitions +typedef uint32_t lfs_size_t; +typedef uint32_t lfs_off_t; + +typedef int32_t lfs_ssize_t; +typedef int32_t lfs_soff_t; + +typedef uint32_t lfs_block_t; + +// Max name size in bytes +#ifndef LFS_NAME_MAX +#define LFS_NAME_MAX 255 +#endif + +// Possible error codes, these are negative to allow +// valid positive return values +enum lfs_error { + LFS_ERR_OK = 0, // No error + LFS_ERR_IO = -5, // Error during device operation + LFS_ERR_CORRUPT = -52, // Corrupted + LFS_ERR_NOENT = -2, // No directory entry + LFS_ERR_EXIST = -17, // Entry already exists + LFS_ERR_NOTDIR = -20, // Entry is not a dir + LFS_ERR_ISDIR = -21, // Entry is a dir + LFS_ERR_NOTEMPTY = -39, // Dir is not empty + LFS_ERR_BADF = -9, // Bad file number + LFS_ERR_INVAL = -22, // Invalid parameter + LFS_ERR_NOSPC = -28, // No space left on device + LFS_ERR_NOMEM = -12, // No more memory available +}; + +// File types +enum lfs_type { + LFS_TYPE_REG = 0x11, + LFS_TYPE_DIR = 0x22, + LFS_TYPE_SUPERBLOCK = 0x2e, +}; + +// File open flags +enum lfs_open_flags { + // open flags + LFS_O_RDONLY = 1, // Open a file as read only + LFS_O_WRONLY = 2, // Open a file as write only + LFS_O_RDWR = 3, // Open a file as read and write + LFS_O_CREAT = 0x0100, // Create a file if it does not exist + LFS_O_EXCL = 0x0200, // Fail if a file already exists + LFS_O_TRUNC = 0x0400, // Truncate the existing file to zero size + LFS_O_APPEND = 0x0800, // Move to end of file on every write + + // internally used flags + LFS_F_DIRTY = 0x10000, // File does not match storage + LFS_F_WRITING = 0x20000, // File has been written since last flush + LFS_F_READING = 0x40000, // File has been read since last flush + LFS_F_ERRED = 0x80000, // An error occured during write +}; + +// File seek flags +enum lfs_whence_flags { + LFS_SEEK_SET = 0, // Seek relative to an absolute position + LFS_SEEK_CUR = 1, // Seek relative to the current file position + LFS_SEEK_END = 2, // Seek relative to the end of the file +}; + + +// Configuration provided during initialization of the littlefs +struct lfs_config { + // Opaque user provided context that can be used to pass + // information to the block device operations + void *context; + + // Read a region in a block. Negative error codes are propogated + // to the user. + int (*read)(const struct lfs_config *c, lfs_block_t block, + lfs_off_t off, void *buffer, lfs_size_t size); + + // Program a region in a block. The block must have previously + // been erased. Negative error codes are propogated to the user. + // May return LFS_ERR_CORRUPT if the block should be considered bad. + int (*prog)(const struct lfs_config *c, lfs_block_t block, + lfs_off_t off, const void *buffer, lfs_size_t size); + + // Erase a block. A block must be erased before being programmed. + // The state of an erased block is undefined. Negative error codes + // are propogated to the user. + // May return LFS_ERR_CORRUPT if the block should be considered bad. + int (*erase)(const struct lfs_config *c, lfs_block_t block); + + // Sync the state of the underlying block device. Negative error codes + // are propogated to the user. + int (*sync)(const struct lfs_config *c); + + // Minimum size of a block read. This determines the size of read buffers. + // This may be larger than the physical read size to improve performance + // by caching more of the block device. + lfs_size_t read_size; + + // Minimum size of a block program. This determines the size of program + // buffers. This may be larger than the physical program size to improve + // performance by caching more of the block device. + // Must be a multiple of the read size. + lfs_size_t prog_size; + + // Size of an erasable block. This does not impact ram consumption and + // may be larger than the physical erase size. However, this should be + // kept small as each file currently takes up an entire block. + // Must be a multiple of the program size. + lfs_size_t block_size; + + // Number of erasable blocks on the device. + lfs_size_t block_count; + + // Number of blocks to lookahead during block allocation. A larger + // lookahead reduces the number of passes required to allocate a block. + // The lookahead buffer requires only 1 bit per block so it can be quite + // large with little ram impact. Should be a multiple of 32. + lfs_size_t lookahead; + + // Optional, statically allocated read buffer. Must be read sized. + void *read_buffer; + + // Optional, statically allocated program buffer. Must be program sized. + void *prog_buffer; + + // Optional, statically allocated lookahead buffer. Must be 1 bit per + // lookahead block. + void *lookahead_buffer; + + // Optional, statically allocated buffer for files. Must be program sized. + // If enabled, only one file may be opened at a time. + void *file_buffer; +}; + +// Optional configuration provided during lfs_file_opencfg +struct lfs_file_config { + // Optional, statically allocated buffer for files. Must be program sized. + // If NULL, malloc will be used by default. + void *buffer; +}; + +// File info structure +struct lfs_info { + // Type of the file, either LFS_TYPE_REG or LFS_TYPE_DIR + uint8_t type; + + // Size of the file, only valid for REG files + lfs_size_t size; + + // Name of the file stored as a null-terminated string + char name[LFS_NAME_MAX+1]; +}; + + +/// littlefs data structures /// +typedef struct lfs_entry { + lfs_off_t off; + + struct lfs_disk_entry { + uint8_t type; + uint8_t elen; + uint8_t alen; + uint8_t nlen; + union { + struct { + lfs_block_t head; + lfs_size_t size; + } file; + lfs_block_t dir[2]; + } u; + } d; +} lfs_entry_t; + +typedef struct lfs_cache { + lfs_block_t block; + lfs_off_t off; + uint8_t *buffer; +} lfs_cache_t; + +typedef struct lfs_file { + struct lfs_file *next; + lfs_block_t pair[2]; + lfs_off_t poff; + + lfs_block_t head; + lfs_size_t size; + + const struct lfs_file_config *cfg; + uint32_t flags; + lfs_off_t pos; + lfs_block_t block; + lfs_off_t off; + lfs_cache_t cache; +} lfs_file_t; + +typedef struct lfs_dir { + struct lfs_dir *next; + lfs_block_t pair[2]; + lfs_off_t off; + + lfs_block_t head[2]; + lfs_off_t pos; + + struct lfs_disk_dir { + uint32_t rev; + lfs_size_t size; + lfs_block_t tail[2]; + } d; +} lfs_dir_t; + +typedef struct lfs_superblock { + lfs_off_t off; + + struct lfs_disk_superblock { + uint8_t type; + uint8_t elen; + uint8_t alen; + uint8_t nlen; + lfs_block_t root[2]; + uint32_t block_size; + uint32_t block_count; + uint32_t version; + char magic[8]; + } d; +} lfs_superblock_t; + +typedef struct lfs_free { + lfs_block_t off; + lfs_block_t size; + lfs_block_t i; + lfs_block_t ack; + uint32_t *buffer; +} lfs_free_t; + +// The littlefs type +typedef struct lfs { + const struct lfs_config *cfg; + + lfs_block_t root[2]; + lfs_file_t *files; + lfs_dir_t *dirs; + + lfs_cache_t rcache; + lfs_cache_t pcache; + + lfs_free_t free; + bool deorphaned; +} lfs_t; + + +/// Filesystem functions /// + +// Format a block device with the littlefs +// +// Requires a littlefs object and config struct. This clobbers the littlefs +// object, and does not leave the filesystem mounted. The config struct must +// be zeroed for defaults and backwards compatibility. +// +// Returns a negative error code on failure. +int lfs_format(lfs_t *lfs, const struct lfs_config *config); + +// Mounts a littlefs +// +// Requires a littlefs object and config struct. Multiple filesystems +// may be mounted simultaneously with multiple littlefs objects. Both +// lfs and config must be allocated while mounted. The config struct must +// be zeroed for defaults and backwards compatibility. +// +// Returns a negative error code on failure. +int lfs_mount(lfs_t *lfs, const struct lfs_config *config); + +// Unmounts a littlefs +// +// Does nothing besides releasing any allocated resources. +// Returns a negative error code on failure. +int lfs_unmount(lfs_t *lfs); + +/// General operations /// + +// Removes a file or directory +// +// If removing a directory, the directory must be empty. +// Returns a negative error code on failure. +int lfs_remove(lfs_t *lfs, const char *path); + +// Rename or move a file or directory +// +// If the destination exists, it must match the source in type. +// If the destination is a directory, the directory must be empty. +// +// Returns a negative error code on failure. +int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath); + +// Find info about a file or directory +// +// Fills out the info structure, based on the specified file or directory. +// Returns a negative error code on failure. +int lfs_stat(lfs_t *lfs, const char *path, struct lfs_info *info); + + +/// File operations /// + +// Open a file +// +// The mode that the file is opened in is determined by the flags, which +// are values from the enum lfs_open_flags that are bitwise-ored together. +// +// Returns a negative error code on failure. +int lfs_file_open(lfs_t *lfs, lfs_file_t *file, + const char *path, int flags); + +// Open a file with extra configuration +// +// The mode that the file is opened in is determined by the flags, which +// are values from the enum lfs_open_flags that are bitwise-ored together. +// +// The config struct provides additional config options per file as described +// above. The config struct must be allocated while the file is open, and the +// config struct must be zeroed for defaults and backwards compatibility. +// +// Returns a negative error code on failure. +int lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file, + const char *path, int flags, + const struct lfs_file_config *config); + +// Close a file +// +// Any pending writes are written out to storage as though +// sync had been called and releases any allocated resources. +// +// Returns a negative error code on failure. +int lfs_file_close(lfs_t *lfs, lfs_file_t *file); + +// Synchronize a file on storage +// +// Any pending writes are written out to storage. +// Returns a negative error code on failure. +int lfs_file_sync(lfs_t *lfs, lfs_file_t *file); + +// Read data from file +// +// Takes a buffer and size indicating where to store the read data. +// Returns the number of bytes read, or a negative error code on failure. +lfs_ssize_t lfs_file_read(lfs_t *lfs, lfs_file_t *file, + void *buffer, lfs_size_t size); + +// Write data to file +// +// Takes a buffer and size indicating the data to write. The file will not +// actually be updated on the storage until either sync or close is called. +// +// Returns the number of bytes written, or a negative error code on failure. +lfs_ssize_t lfs_file_write(lfs_t *lfs, lfs_file_t *file, + const void *buffer, lfs_size_t size); + +// Change the position of the file +// +// The change in position is determined by the offset and whence flag. +// Returns the old position of the file, or a negative error code on failure. +lfs_soff_t lfs_file_seek(lfs_t *lfs, lfs_file_t *file, + lfs_soff_t off, int whence); + +// Truncates the size of the file to the specified size +// +// Returns a negative error code on failure. +int lfs_file_truncate(lfs_t *lfs, lfs_file_t *file, lfs_off_t size); + +// Return the position of the file +// +// Equivalent to lfs_file_seek(lfs, file, 0, LFS_SEEK_CUR) +// Returns the position of the file, or a negative error code on failure. +lfs_soff_t lfs_file_tell(lfs_t *lfs, lfs_file_t *file); + +// Change the position of the file to the beginning of the file +// +// Equivalent to lfs_file_seek(lfs, file, 0, LFS_SEEK_CUR) +// Returns a negative error code on failure. +int lfs_file_rewind(lfs_t *lfs, lfs_file_t *file); + +// Return the size of the file +// +// Similar to lfs_file_seek(lfs, file, 0, LFS_SEEK_END) +// Returns the size of the file, or a negative error code on failure. +lfs_soff_t lfs_file_size(lfs_t *lfs, lfs_file_t *file); + + +/// Directory operations /// + +// Create a directory +// +// Returns a negative error code on failure. +int lfs_mkdir(lfs_t *lfs, const char *path); + +// Open a directory +// +// Once open a directory can be used with read to iterate over files. +// Returns a negative error code on failure. +int lfs_dir_open(lfs_t *lfs, lfs_dir_t *dir, const char *path); + +// Close a directory +// +// Releases any allocated resources. +// Returns a negative error code on failure. +int lfs_dir_close(lfs_t *lfs, lfs_dir_t *dir); + +// Read an entry in the directory +// +// Fills out the info structure, based on the specified file or directory. +// Returns a negative error code on failure. +int lfs_dir_read(lfs_t *lfs, lfs_dir_t *dir, struct lfs_info *info); + +// Change the position of the directory +// +// The new off must be a value previous returned from tell and specifies +// an absolute offset in the directory seek. +// +// Returns a negative error code on failure. +int lfs_dir_seek(lfs_t *lfs, lfs_dir_t *dir, lfs_off_t off); + +// Return the position of the directory +// +// The returned offset is only meant to be consumed by seek and may not make +// sense, but does indicate the current position in the directory iteration. +// +// Returns the position of the directory, or a negative error code on failure. +lfs_soff_t lfs_dir_tell(lfs_t *lfs, lfs_dir_t *dir); + +// Change the position of the directory to the beginning of the directory +// +// Returns a negative error code on failure. +int lfs_dir_rewind(lfs_t *lfs, lfs_dir_t *dir); + + +/// Miscellaneous littlefs specific operations /// + +// Traverse through all blocks in use by the filesystem +// +// The provided callback will be called with each block address that is +// currently in use by the filesystem. This can be used to determine which +// blocks are in use or how much of the storage is available. +// +// Returns a negative error code on failure. +int lfs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data); + +// Prunes any recoverable errors that may have occured in the filesystem +// +// Not needed to be called by user unless an operation is interrupted +// but the filesystem is still mounted. This is already called on first +// allocation. +// +// Returns a negative error code on failure. +int lfs_deorphan(lfs_t *lfs); + + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif |