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pigweed / third_party / github / littlefs-project / littlefs / refs/heads/upstream/devel / . / lfs.c
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/*
* The little filesystem
*
* Copyright (c) 2022, The littlefs authors.
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
*/
#include "lfs.h"
#include "lfs_util.h"
// some constants used throughout the code
#define LFS_BLOCK_NULL ((lfs_block_t)-1)
#define LFS_BLOCK_INLINE ((lfs_block_t)-2)
enum {
LFS_OK_RELOCATED = 1,
LFS_OK_DROPPED = 2,
LFS_OK_ORPHANED = 3,
};
enum {
LFS_CMP_EQ = 0,
LFS_CMP_LT = 1,
LFS_CMP_GT = 2,
};
/// Caching block device operations ///
static inline void lfs_cache_drop(lfs_t *lfs, lfs_cache_t *rcache) {
// do not zero, cheaper if cache is readonly or only going to be
// written with identical data (during relocates)
(void)lfs;
rcache->block = LFS_BLOCK_NULL;
}
static inline void lfs_cache_zero(lfs_t *lfs, lfs_cache_t *pcache) {
// zero to avoid information leak
memset(pcache->buffer, 0xff, lfs->cfg->cache_size);
pcache->block = LFS_BLOCK_NULL;
}
static int lfs_bd_read(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache, lfs_size_t hint,
lfs_block_t block, lfs_off_t off,
void *buffer, lfs_size_t size) {
uint8_t *data = buffer;
if (off+size > lfs->cfg->block_size
|| (lfs->block_count && block >= lfs->block_count)) {
return LFS_ERR_CORRUPT;
}
while (size > 0) {
lfs_size_t diff = size;
if (pcache && block == pcache->block &&
off < pcache->off + pcache->size) {
if (off >= pcache->off) {
// is already in pcache?
diff = lfs_min(diff, pcache->size - (off-pcache->off));
memcpy(data, &pcache->buffer[off-pcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
// pcache takes priority
diff = lfs_min(diff, pcache->off-off);
}
if (block == rcache->block &&
off < rcache->off + rcache->size) {
if (off >= rcache->off) {
// is already in rcache?
diff = lfs_min(diff, rcache->size - (off-rcache->off));
memcpy(data, &rcache->buffer[off-rcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
// rcache takes priority
diff = lfs_min(diff, rcache->off-off);
}
if (size >= hint && off % lfs->cfg->read_size == 0 &&
size >= lfs->cfg->read_size) {
// bypass cache?
diff = lfs_aligndown(diff, lfs->cfg->read_size);
int err = lfs->cfg->read(lfs->cfg, block, off, data, diff);
LFS_ASSERT(err <= 0);
if (err) {
return err;
}
data += diff;
off += diff;
size -= diff;
continue;
}
// load to cache, first condition can no longer fail
LFS_ASSERT(!lfs->block_count || block < lfs->block_count);
rcache->block = block;
rcache->off = lfs_aligndown(off, lfs->cfg->read_size);
rcache->size = lfs_min(
lfs_min(
lfs_alignup(off+hint, lfs->cfg->read_size),
lfs->cfg->block_size)
- rcache->off,
lfs->cfg->cache_size);
int err = lfs->cfg->read(lfs->cfg, rcache->block,
rcache->off, rcache->buffer, rcache->size);
LFS_ASSERT(err <= 0);
if (err) {
return err;
}
}
return 0;
}
static int lfs_bd_cmp(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache, lfs_size_t hint,
lfs_block_t block, lfs_off_t off,
const void *buffer, lfs_size_t size) {
const uint8_t *data = buffer;
lfs_size_t diff = 0;
for (lfs_off_t i = 0; i < size; i += diff) {
uint8_t dat[8];
diff = lfs_min(size-i, sizeof(dat));
int err = lfs_bd_read(lfs,
pcache, rcache, hint-i,
block, off+i, &dat, diff);
if (err) {
return err;
}
int res = memcmp(dat, data + i, diff);
if (res) {
return res < 0 ? LFS_CMP_LT : LFS_CMP_GT;
}
}
return LFS_CMP_EQ;
}
static int lfs_bd_crc(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache, lfs_size_t hint,
lfs_block_t block, lfs_off_t off, lfs_size_t size, uint32_t *crc) {
lfs_size_t diff = 0;
for (lfs_off_t i = 0; i < size; i += diff) {
uint8_t dat[8];
diff = lfs_min(size-i, sizeof(dat));
int err = lfs_bd_read(lfs,
pcache, rcache, hint-i,
block, off+i, &dat, diff);
if (err) {
return err;
}
*crc = lfs_crc(*crc, &dat, diff);
}
return 0;
}
#ifndef LFS_READONLY
static int lfs_bd_flush(lfs_t *lfs,
lfs_cache_t *pcache, lfs_cache_t *rcache, bool validate) {
if (pcache->block != LFS_BLOCK_NULL && pcache->block != LFS_BLOCK_INLINE) {
LFS_ASSERT(pcache->block < lfs->block_count);
lfs_size_t diff = lfs_alignup(pcache->size, lfs->cfg->prog_size);
int err = lfs->cfg->prog(lfs->cfg, pcache->block,
pcache->off, pcache->buffer, diff);
LFS_ASSERT(err <= 0);
if (err) {
return err;
}
if (validate) {
// check data on disk
lfs_cache_drop(lfs, rcache);
int res = lfs_bd_cmp(lfs,
NULL, rcache, diff,
pcache->block, pcache->off, pcache->buffer, diff);
if (res < 0) {
return res;
}
if (res != LFS_CMP_EQ) {
return LFS_ERR_CORRUPT;
}
}
lfs_cache_zero(lfs, pcache);
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_bd_sync(lfs_t *lfs,
lfs_cache_t *pcache, lfs_cache_t *rcache, bool validate) {
lfs_cache_drop(lfs, rcache);
int err = lfs_bd_flush(lfs, pcache, rcache, validate);
if (err) {
return err;
}
err = lfs->cfg->sync(lfs->cfg);
LFS_ASSERT(err <= 0);
return err;
}
#endif
#ifndef LFS_READONLY
static int lfs_bd_prog(lfs_t *lfs,
lfs_cache_t *pcache, lfs_cache_t *rcache, bool validate,
lfs_block_t block, lfs_off_t off,
const void *buffer, lfs_size_t size) {
const uint8_t *data = buffer;
LFS_ASSERT(block == LFS_BLOCK_INLINE || block < lfs->block_count);
LFS_ASSERT(off + size <= lfs->cfg->block_size);
while (size > 0) {
if (block == pcache->block &&
off >= pcache->off &&
off < pcache->off + lfs->cfg->cache_size) {
// already fits in pcache?
lfs_size_t diff = lfs_min(size,
lfs->cfg->cache_size - (off-pcache->off));
memcpy(&pcache->buffer[off-pcache->off], data, diff);
data += diff;
off += diff;
size -= diff;
pcache->size = lfs_max(pcache->size, off - pcache->off);
if (pcache->size == lfs->cfg->cache_size) {
// eagerly flush out pcache if we fill up
int err = lfs_bd_flush(lfs, pcache, rcache, validate);
if (err) {
return err;
}
}
continue;
}
// pcache must have been flushed, either by programming and
// entire block or manually flushing the pcache
LFS_ASSERT(pcache->block == LFS_BLOCK_NULL);
// prepare pcache, first condition can no longer fail
pcache->block = block;
pcache->off = lfs_aligndown(off, lfs->cfg->prog_size);
pcache->size = 0;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_bd_erase(lfs_t *lfs, lfs_block_t block) {
LFS_ASSERT(block < lfs->block_count);
int err = lfs->cfg->erase(lfs->cfg, block);
LFS_ASSERT(err <= 0);
return err;
}
#endif
/// Small type-level utilities ///
// some operations on paths
static inline lfs_size_t lfs_path_namelen(const char *path) {
return strcspn(path, "/");
}
static inline bool lfs_path_islast(const char *path) {
lfs_size_t namelen = lfs_path_namelen(path);
return path[namelen + strspn(path + namelen, "/")] == '\0';
}
static inline bool lfs_path_isdir(const char *path) {
return path[lfs_path_namelen(path)] != '\0';
}
// operations on block pairs
static inline void lfs_pair_swap(lfs_block_t pair[2]) {
lfs_block_t t = pair[0];
pair[0] = pair[1];
pair[1] = t;
}
static inline bool lfs_pair_isnull(const lfs_block_t pair[2]) {
return pair[0] == LFS_BLOCK_NULL || pair[1] == LFS_BLOCK_NULL;
}
static inline int lfs_pair_cmp(
const lfs_block_t paira[2],
const lfs_block_t pairb[2]) {
return !(paira[0] == pairb[0] || paira[1] == pairb[1] ||
paira[0] == pairb[1] || paira[1] == pairb[0]);
}
static inline bool lfs_pair_issync(
const lfs_block_t paira[2],
const lfs_block_t pairb[2]) {
return (paira[0] == pairb[0] && paira[1] == pairb[1]) ||
(paira[0] == pairb[1] && paira[1] == pairb[0]);
}
static inline void lfs_pair_fromle32(lfs_block_t pair[2]) {
pair[0] = lfs_fromle32(pair[0]);
pair[1] = lfs_fromle32(pair[1]);
}
#ifndef LFS_READONLY
static inline void lfs_pair_tole32(lfs_block_t pair[2]) {
pair[0] = lfs_tole32(pair[0]);
pair[1] = lfs_tole32(pair[1]);
}
#endif
// operations on 32-bit entry tags
typedef uint32_t lfs_tag_t;
typedef int32_t lfs_stag_t;
#define LFS_MKTAG(type, id, size) \
(((lfs_tag_t)(type) << 20) | ((lfs_tag_t)(id) << 10) | (lfs_tag_t)(size))
#define LFS_MKTAG_IF(cond, type, id, size) \
((cond) ? LFS_MKTAG(type, id, size) : LFS_MKTAG(LFS_FROM_NOOP, 0, 0))
#define LFS_MKTAG_IF_ELSE(cond, type1, id1, size1, type2, id2, size2) \
((cond) ? LFS_MKTAG(type1, id1, size1) : LFS_MKTAG(type2, id2, size2))
static inline bool lfs_tag_isvalid(lfs_tag_t tag) {
return !(tag & 0x80000000);
}
static inline bool lfs_tag_isdelete(lfs_tag_t tag) {
return ((int32_t)(tag << 22) >> 22) == -1;
}
static inline uint16_t lfs_tag_type1(lfs_tag_t tag) {
return (tag & 0x70000000) >> 20;
}
static inline uint16_t lfs_tag_type2(lfs_tag_t tag) {
return (tag & 0x78000000) >> 20;
}
static inline uint16_t lfs_tag_type3(lfs_tag_t tag) {
return (tag & 0x7ff00000) >> 20;
}
static inline uint8_t lfs_tag_chunk(lfs_tag_t tag) {
return (tag & 0x0ff00000) >> 20;
}
static inline int8_t lfs_tag_splice(lfs_tag_t tag) {
return (int8_t)lfs_tag_chunk(tag);
}
static inline uint16_t lfs_tag_id(lfs_tag_t tag) {
return (tag & 0x000ffc00) >> 10;
}
static inline lfs_size_t lfs_tag_size(lfs_tag_t tag) {
return tag & 0x000003ff;
}
static inline lfs_size_t lfs_tag_dsize(lfs_tag_t tag) {
return sizeof(tag) + lfs_tag_size(tag + lfs_tag_isdelete(tag));
}
// operations on attributes in attribute lists
struct lfs_mattr {
lfs_tag_t tag;
const void *buffer;
};
struct lfs_diskoff {
lfs_block_t block;
lfs_off_t off;
};
#define LFS_MKATTRS(...) \
(struct lfs_mattr[]){__VA_ARGS__}, \
sizeof((struct lfs_mattr[]){__VA_ARGS__}) / sizeof(struct lfs_mattr)
// operations on global state
static inline void lfs_gstate_xor(lfs_gstate_t *a, const lfs_gstate_t *b) {
a->tag ^= b->tag;
a->pair[0] ^= b->pair[0];
a->pair[1] ^= b->pair[1];
}
static inline bool lfs_gstate_iszero(const lfs_gstate_t *a) {
return a->tag == 0
&& a->pair[0] == 0
&& a->pair[1] == 0;
}
#ifndef LFS_READONLY
static inline bool lfs_gstate_hasorphans(const lfs_gstate_t *a) {
return lfs_tag_size(a->tag);
}
static inline uint8_t lfs_gstate_getorphans(const lfs_gstate_t *a) {
return lfs_tag_size(a->tag) & 0x1ff;
}
static inline bool lfs_gstate_hasmove(const lfs_gstate_t *a) {
return lfs_tag_type1(a->tag);
}
#endif
static inline bool lfs_gstate_needssuperblock(const lfs_gstate_t *a) {
return lfs_tag_size(a->tag) >> 9;
}
static inline bool lfs_gstate_hasmovehere(const lfs_gstate_t *a,
const lfs_block_t *pair) {
return lfs_tag_type1(a->tag) && lfs_pair_cmp(a->pair, pair) == 0;
}
static inline void lfs_gstate_fromle32(lfs_gstate_t *a) {
a->tag = lfs_fromle32(a->tag);
a->pair[0] = lfs_fromle32(a->pair[0]);
a->pair[1] = lfs_fromle32(a->pair[1]);
}
#ifndef LFS_READONLY
static inline void lfs_gstate_tole32(lfs_gstate_t *a) {
a->tag = lfs_tole32(a->tag);
a->pair[0] = lfs_tole32(a->pair[0]);
a->pair[1] = lfs_tole32(a->pair[1]);
}
#endif
// operations on forward-CRCs used to track erased state
struct lfs_fcrc {
lfs_size_t size;
uint32_t crc;
};
static void lfs_fcrc_fromle32(struct lfs_fcrc *fcrc) {
fcrc->size = lfs_fromle32(fcrc->size);
fcrc->crc = lfs_fromle32(fcrc->crc);
}
#ifndef LFS_READONLY
static void lfs_fcrc_tole32(struct lfs_fcrc *fcrc) {
fcrc->size = lfs_tole32(fcrc->size);
fcrc->crc = lfs_tole32(fcrc->crc);
}
#endif
// other endianness operations
static void lfs_ctz_fromle32(struct lfs_ctz *ctz) {
ctz->head = lfs_fromle32(ctz->head);
ctz->size = lfs_fromle32(ctz->size);
}
#ifndef LFS_READONLY
static void lfs_ctz_tole32(struct lfs_ctz *ctz) {
ctz->head = lfs_tole32(ctz->head);
ctz->size = lfs_tole32(ctz->size);
}
#endif
static inline void lfs_superblock_fromle32(lfs_superblock_t *superblock) {
superblock->version = lfs_fromle32(superblock->version);
superblock->block_size = lfs_fromle32(superblock->block_size);
superblock->block_count = lfs_fromle32(superblock->block_count);
superblock->name_max = lfs_fromle32(superblock->name_max);
superblock->file_max = lfs_fromle32(superblock->file_max);
superblock->attr_max = lfs_fromle32(superblock->attr_max);
}
#ifndef LFS_READONLY
static inline void lfs_superblock_tole32(lfs_superblock_t *superblock) {
superblock->version = lfs_tole32(superblock->version);
superblock->block_size = lfs_tole32(superblock->block_size);
superblock->block_count = lfs_tole32(superblock->block_count);
superblock->name_max = lfs_tole32(superblock->name_max);
superblock->file_max = lfs_tole32(superblock->file_max);
superblock->attr_max = lfs_tole32(superblock->attr_max);
}
#endif
#ifndef LFS_NO_ASSERT
static bool lfs_mlist_isopen(struct lfs_mlist *head,
struct lfs_mlist *node) {
for (struct lfs_mlist **p = &head; *p; p = &(*p)->next) {
if (*p == (struct lfs_mlist*)node) {
return true;
}
}
return false;
}
#endif
static void lfs_mlist_remove(lfs_t *lfs, struct lfs_mlist *mlist) {
for (struct lfs_mlist **p = &lfs->mlist; *p; p = &(*p)->next) {
if (*p == mlist) {
*p = (*p)->next;
break;
}
}
}
static void lfs_mlist_append(lfs_t *lfs, struct lfs_mlist *mlist) {
mlist->next = lfs->mlist;
lfs->mlist = mlist;
}
// some other filesystem operations
static uint32_t lfs_fs_disk_version(lfs_t *lfs) {
(void)lfs;
#ifdef LFS_MULTIVERSION
if (lfs->cfg->disk_version) {
return lfs->cfg->disk_version;
} else
#endif
{
return LFS_DISK_VERSION;
}
}
static uint16_t lfs_fs_disk_version_major(lfs_t *lfs) {
return 0xffff & (lfs_fs_disk_version(lfs) >> 16);
}
static uint16_t lfs_fs_disk_version_minor(lfs_t *lfs) {
return 0xffff & (lfs_fs_disk_version(lfs) >> 0);
}
/// Internal operations predeclared here ///
#ifndef LFS_READONLY
static int lfs_dir_commit(lfs_t *lfs, lfs_mdir_t *dir,
const struct lfs_mattr *attrs, int attrcount);
static int lfs_dir_compact(lfs_t *lfs,
lfs_mdir_t *dir, const struct lfs_mattr *attrs, int attrcount,
lfs_mdir_t *source, uint16_t begin, uint16_t end);
static lfs_ssize_t lfs_file_flushedwrite(lfs_t *lfs, lfs_file_t *file,
const void *buffer, lfs_size_t size);
static lfs_ssize_t lfs_file_write_(lfs_t *lfs, lfs_file_t *file,
const void *buffer, lfs_size_t size);
static int lfs_file_sync_(lfs_t *lfs, lfs_file_t *file);
static int lfs_file_outline(lfs_t *lfs, lfs_file_t *file);
static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file);
static int lfs_fs_deorphan(lfs_t *lfs, bool powerloss);
static int lfs_fs_preporphans(lfs_t *lfs, int8_t orphans);
static void lfs_fs_prepmove(lfs_t *lfs,
uint16_t id, const lfs_block_t pair[2]);
static int lfs_fs_pred(lfs_t *lfs, const lfs_block_t dir[2],
lfs_mdir_t *pdir);
static lfs_stag_t lfs_fs_parent(lfs_t *lfs, const lfs_block_t dir[2],
lfs_mdir_t *parent);
static int lfs_fs_forceconsistency(lfs_t *lfs);
#endif
static void lfs_fs_prepsuperblock(lfs_t *lfs, bool needssuperblock);
#ifdef LFS_MIGRATE
static int lfs1_traverse(lfs_t *lfs,
int (*cb)(void*, lfs_block_t), void *data);
#endif
static int lfs_dir_rewind_(lfs_t *lfs, lfs_dir_t *dir);
static lfs_ssize_t lfs_file_flushedread(lfs_t *lfs, lfs_file_t *file,
void *buffer, lfs_size_t size);
static lfs_ssize_t lfs_file_read_(lfs_t *lfs, lfs_file_t *file,
void *buffer, lfs_size_t size);
static int lfs_file_close_(lfs_t *lfs, lfs_file_t *file);
static lfs_soff_t lfs_file_size_(lfs_t *lfs, lfs_file_t *file);
static lfs_ssize_t lfs_fs_size_(lfs_t *lfs);
static int lfs_fs_traverse_(lfs_t *lfs,
int (*cb)(void *data, lfs_block_t block), void *data,
bool includeorphans);
static int lfs_deinit(lfs_t *lfs);
static int lfs_unmount_(lfs_t *lfs);
/// Block allocator ///
// allocations should call this when all allocated blocks are committed to
// the filesystem
//
// after a checkpoint, the block allocator may realloc any untracked blocks
static void lfs_alloc_ckpoint(lfs_t *lfs) {
lfs->lookahead.ckpoint = lfs->block_count;
}
// drop the lookahead buffer, this is done during mounting and failed
// traversals in order to avoid invalid lookahead state
static void lfs_alloc_drop(lfs_t *lfs) {
lfs->lookahead.size = 0;
lfs->lookahead.next = 0;
lfs_alloc_ckpoint(lfs);
}
#ifndef LFS_READONLY
static int lfs_alloc_lookahead(void *p, lfs_block_t block) {
lfs_t *lfs = (lfs_t*)p;
lfs_block_t off = ((block - lfs->lookahead.start)
+ lfs->block_count) % lfs->block_count;
if (off < lfs->lookahead.size) {
lfs->lookahead.buffer[off / 8] |= 1U << (off % 8);
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_alloc_scan(lfs_t *lfs) {
// move lookahead buffer to the first unused block
//
// note we limit the lookahead buffer to at most the amount of blocks
// checkpointed, this prevents the math in lfs_alloc from underflowing
lfs->lookahead.start = (lfs->lookahead.start + lfs->lookahead.next)
% lfs->block_count;
lfs->lookahead.next = 0;
lfs->lookahead.size = lfs_min(
8*lfs->cfg->lookahead_size,
lfs->lookahead.ckpoint);
// find mask of free blocks from tree
memset(lfs->lookahead.buffer, 0, lfs->cfg->lookahead_size);
int err = lfs_fs_traverse_(lfs, lfs_alloc_lookahead, lfs, true);
if (err) {
lfs_alloc_drop(lfs);
return err;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_alloc(lfs_t *lfs, lfs_block_t *block) {
while (true) {
// scan our lookahead buffer for free blocks
while (lfs->lookahead.next < lfs->lookahead.size) {
if (!(lfs->lookahead.buffer[lfs->lookahead.next / 8]
& (1U << (lfs->lookahead.next % 8)))) {
// found a free block
*block = (lfs->lookahead.start + lfs->lookahead.next)
% lfs->block_count;
// eagerly find next free block to maximize how many blocks
// lfs_alloc_ckpoint makes available for scanning
while (true) {
lfs->lookahead.next += 1;
lfs->lookahead.ckpoint -= 1;
if (lfs->lookahead.next >= lfs->lookahead.size
|| !(lfs->lookahead.buffer[lfs->lookahead.next / 8]
& (1U << (lfs->lookahead.next % 8)))) {
return 0;
}
}
}
lfs->lookahead.next += 1;
lfs->lookahead.ckpoint -= 1;
}
// In order to keep our block allocator from spinning forever when our
// filesystem is full, we mark points where there are no in-flight
// allocations with a checkpoint before starting a set of allocations.
//
// If we've looked at all blocks since the last checkpoint, we report
// the filesystem as out of storage.
//
if (lfs->lookahead.ckpoint <= 0) {
LFS_ERROR("No more free space 0x%"PRIx32,
(lfs->lookahead.start + lfs->lookahead.next)
% lfs->block_count);
return LFS_ERR_NOSPC;
}
// No blocks in our lookahead buffer, we need to scan the filesystem for
// unused blocks in the next lookahead window.
int err = lfs_alloc_scan(lfs);
if(err) {
return err;
}
}
}
#endif
/// Metadata pair and directory operations ///
static lfs_stag_t lfs_dir_getslice(lfs_t *lfs, const lfs_mdir_t *dir,
lfs_tag_t gmask, lfs_tag_t gtag,
lfs_off_t goff, void *gbuffer, lfs_size_t gsize) {
lfs_off_t off = dir->off;
lfs_tag_t ntag = dir->etag;
lfs_stag_t gdiff = 0;
// synthetic moves
if (lfs_gstate_hasmovehere(&lfs->gdisk, dir->pair) &&
lfs_tag_id(gmask) != 0) {
if (lfs_tag_id(lfs->gdisk.tag) == lfs_tag_id(gtag)) {
return LFS_ERR_NOENT;
} else if (lfs_tag_id(lfs->gdisk.tag) < lfs_tag_id(gtag)) {
gdiff -= LFS_MKTAG(0, 1, 0);
}
}
// iterate over dir block backwards (for faster lookups)
while (off >= sizeof(lfs_tag_t) + lfs_tag_dsize(ntag)) {
off -= lfs_tag_dsize(ntag);
lfs_tag_t tag = ntag;
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, sizeof(ntag),
dir->pair[0], off, &ntag, sizeof(ntag));
LFS_ASSERT(err <= 0);
if (err) {
return err;
}
ntag = (lfs_frombe32(ntag) ^ tag) & 0x7fffffff;
if (lfs_tag_id(gmask) != 0 &&
lfs_tag_type1(tag) == LFS_TYPE_SPLICE &&
lfs_tag_id(tag) <= lfs_tag_id(gtag - gdiff)) {
if (tag == (LFS_MKTAG(LFS_TYPE_CREATE, 0, 0) |
(LFS_MKTAG(0, 0x3ff, 0) & (gtag - gdiff)))) {
// found where we were created
return LFS_ERR_NOENT;
}
// move around splices
gdiff += LFS_MKTAG(0, lfs_tag_splice(tag), 0);
}
if ((gmask & tag) == (gmask & (gtag - gdiff))) {
if (lfs_tag_isdelete(tag)) {
return LFS_ERR_NOENT;
}
lfs_size_t diff = lfs_min(lfs_tag_size(tag), gsize);
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, diff,
dir->pair[0], off+sizeof(tag)+goff, gbuffer, diff);
LFS_ASSERT(err <= 0);
if (err) {
return err;
}
memset((uint8_t*)gbuffer + diff, 0, gsize - diff);
return tag + gdiff;
}
}
return LFS_ERR_NOENT;
}
static lfs_stag_t lfs_dir_get(lfs_t *lfs, const lfs_mdir_t *dir,
lfs_tag_t gmask, lfs_tag_t gtag, void *buffer) {
return lfs_dir_getslice(lfs, dir,
gmask, gtag,
0, buffer, lfs_tag_size(gtag));
}
static int lfs_dir_getread(lfs_t *lfs, const lfs_mdir_t *dir,
const lfs_cache_t *pcache, lfs_cache_t *rcache, lfs_size_t hint,
lfs_tag_t gmask, lfs_tag_t gtag,
lfs_off_t off, void *buffer, lfs_size_t size) {
uint8_t *data = buffer;
if (off+size > lfs->cfg->block_size) {
return LFS_ERR_CORRUPT;
}
while (size > 0) {
lfs_size_t diff = size;
if (pcache && pcache->block == LFS_BLOCK_INLINE &&
off < pcache->off + pcache->size) {
if (off >= pcache->off) {
// is already in pcache?
diff = lfs_min(diff, pcache->size - (off-pcache->off));
memcpy(data, &pcache->buffer[off-pcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
// pcache takes priority
diff = lfs_min(diff, pcache->off-off);
}
if (rcache->block == LFS_BLOCK_INLINE &&
off < rcache->off + rcache->size) {
if (off >= rcache->off) {
// is already in rcache?
diff = lfs_min(diff, rcache->size - (off-rcache->off));
memcpy(data, &rcache->buffer[off-rcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
}
// load to cache, first condition can no longer fail
rcache->block = LFS_BLOCK_INLINE;
rcache->off = lfs_aligndown(off, lfs->cfg->read_size);
rcache->size = lfs_min(lfs_alignup(off+hint, lfs->cfg->read_size),
lfs->cfg->cache_size);
int err = lfs_dir_getslice(lfs, dir, gmask, gtag,
rcache->off, rcache->buffer, rcache->size);
if (err < 0) {
return err;
}
}
return 0;
}
#ifndef LFS_READONLY
static int lfs_dir_traverse_filter(void *p,
lfs_tag_t tag, const void *buffer) {
lfs_tag_t *filtertag = p;
(void)buffer;
// which mask depends on unique bit in tag structure
uint32_t mask = (tag & LFS_MKTAG(0x100, 0, 0))
? LFS_MKTAG(0x7ff, 0x3ff, 0)
: LFS_MKTAG(0x700, 0x3ff, 0);
// check for redundancy
if ((mask & tag) == (mask & *filtertag) ||
lfs_tag_isdelete(*filtertag) ||
(LFS_MKTAG(0x7ff, 0x3ff, 0) & tag) == (
LFS_MKTAG(LFS_TYPE_DELETE, 0, 0) |
(LFS_MKTAG(0, 0x3ff, 0) & *filtertag))) {
*filtertag = LFS_MKTAG(LFS_FROM_NOOP, 0, 0);
return true;
}
// check if we need to adjust for created/deleted tags
if (lfs_tag_type1(tag) == LFS_TYPE_SPLICE &&
lfs_tag_id(tag) <= lfs_tag_id(*filtertag)) {
*filtertag += LFS_MKTAG(0, lfs_tag_splice(tag), 0);
}
return false;
}
#endif
#ifndef LFS_READONLY
// maximum recursive depth of lfs_dir_traverse, the deepest call:
//
// traverse with commit
// '-> traverse with move
// '-> traverse with filter
//
#define LFS_DIR_TRAVERSE_DEPTH 3
struct lfs_dir_traverse {
const lfs_mdir_t *dir;
lfs_off_t off;
lfs_tag_t ptag;
const struct lfs_mattr *attrs;
int attrcount;
lfs_tag_t tmask;
lfs_tag_t ttag;
uint16_t begin;
uint16_t end;
int16_t diff;
int (*cb)(void *data, lfs_tag_t tag, const void *buffer);
void *data;
lfs_tag_t tag;
const void *buffer;
struct lfs_diskoff disk;
};
static int lfs_dir_traverse(lfs_t *lfs,
const lfs_mdir_t *dir, lfs_off_t off, lfs_tag_t ptag,
const struct lfs_mattr *attrs, int attrcount,
lfs_tag_t tmask, lfs_tag_t ttag,
uint16_t begin, uint16_t end, int16_t diff,
int (*cb)(void *data, lfs_tag_t tag, const void *buffer), void *data) {
// This function in inherently recursive, but bounded. To allow tool-based
// analysis without unnecessary code-cost we use an explicit stack
struct lfs_dir_traverse stack[LFS_DIR_TRAVERSE_DEPTH-1];
unsigned sp = 0;
int res;
// iterate over directory and attrs
lfs_tag_t tag;
const void *buffer;
struct lfs_diskoff disk = {0};
while (true) {
{
if (off+lfs_tag_dsize(ptag) < dir->off) {
off += lfs_tag_dsize(ptag);
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, sizeof(tag),
dir->pair[0], off, &tag, sizeof(tag));
if (err) {
return err;
}
tag = (lfs_frombe32(tag) ^ ptag) | 0x80000000;
disk.block = dir->pair[0];
disk.off = off+sizeof(lfs_tag_t);
buffer = &disk;
ptag = tag;
} else if (attrcount > 0) {
tag = attrs[0].tag;
buffer = attrs[0].buffer;
attrs += 1;
attrcount -= 1;
} else {
// finished traversal, pop from stack?
res = 0;
break;
}
// do we need to filter?
lfs_tag_t mask = LFS_MKTAG(0x7ff, 0, 0);
if ((mask & tmask & tag) != (mask & tmask & ttag)) {
continue;
}
if (lfs_tag_id(tmask) != 0) {
LFS_ASSERT(sp < LFS_DIR_TRAVERSE_DEPTH);
// recurse, scan for duplicates, and update tag based on
// creates/deletes
stack[sp] = (struct lfs_dir_traverse){
.dir = dir,
.off = off,
.ptag = ptag,
.attrs = attrs,
.attrcount = attrcount,
.tmask = tmask,
.ttag = ttag,
.begin = begin,
.end = end,
.diff = diff,
.cb = cb,
.data = data,
.tag = tag,
.buffer = buffer,
.disk = disk,
};
sp += 1;
tmask = 0;
ttag = 0;
begin = 0;
end = 0;
diff = 0;
cb = lfs_dir_traverse_filter;
data = &stack[sp-1].tag;
continue;
}
}
popped:
// in filter range?
if (lfs_tag_id(tmask) != 0 &&
!(lfs_tag_id(tag) >= begin && lfs_tag_id(tag) < end)) {
continue;
}
// handle special cases for mcu-side operations
if (lfs_tag_type3(tag) == LFS_FROM_NOOP) {
// do nothing
} else if (lfs_tag_type3(tag) == LFS_FROM_MOVE) {
// Without this condition, lfs_dir_traverse can exhibit an
// extremely expensive O(n^3) of nested loops when renaming.
// This happens because lfs_dir_traverse tries to filter tags by
// the tags in the source directory, triggering a second
// lfs_dir_traverse with its own filter operation.
//
// traverse with commit
// '-> traverse with filter
// '-> traverse with move
// '-> traverse with filter
//
// However we don't actually care about filtering the second set of
// tags, since duplicate tags have no effect when filtering.
//
// This check skips this unnecessary recursive filtering explicitly,
// reducing this runtime from O(n^3) to O(n^2).
if (cb == lfs_dir_traverse_filter) {
continue;
}
// recurse into move
stack[sp] = (struct lfs_dir_traverse){
.dir = dir,
.off = off,
.ptag = ptag,
.attrs = attrs,
.attrcount = attrcount,
.tmask = tmask,
.ttag = ttag,
.begin = begin,
.end = end,
.diff = diff,
.cb = cb,
.data = data,
.tag = LFS_MKTAG(LFS_FROM_NOOP, 0, 0),
};
sp += 1;
uint16_t fromid = lfs_tag_size(tag);
uint16_t toid = lfs_tag_id(tag);
dir = buffer;
off = 0;
ptag = 0xffffffff;
attrs = NULL;
attrcount = 0;
tmask = LFS_MKTAG(0x600, 0x3ff, 0);
ttag = LFS_MKTAG(LFS_TYPE_STRUCT, 0, 0);
begin = fromid;
end = fromid+1;
diff = toid-fromid+diff;
} else if (lfs_tag_type3(tag) == LFS_FROM_USERATTRS) {
for (unsigned i = 0; i < lfs_tag_size(tag); i++) {
const struct lfs_attr *a = buffer;
res = cb(data, LFS_MKTAG(LFS_TYPE_USERATTR + a[i].type,
lfs_tag_id(tag) + diff, a[i].size), a[i].buffer);
if (res < 0) {
return res;
}
if (res) {
break;
}
}
} else {
res = cb(data, tag + LFS_MKTAG(0, diff, 0), buffer);
if (res < 0) {
return res;
}
if (res) {
break;
}
}
}
if (sp > 0) {
// pop from the stack and return, fortunately all pops share
// a destination
dir = stack[sp-1].dir;
off = stack[sp-1].off;
ptag = stack[sp-1].ptag;
attrs = stack[sp-1].attrs;
attrcount = stack[sp-1].attrcount;
tmask = stack[sp-1].tmask;
ttag = stack[sp-1].ttag;
begin = stack[sp-1].begin;
end = stack[sp-1].end;
diff = stack[sp-1].diff;
cb = stack[sp-1].cb;
data = stack[sp-1].data;
tag = stack[sp-1].tag;
buffer = stack[sp-1].buffer;
disk = stack[sp-1].disk;
sp -= 1;
goto popped;
} else {
return res;
}
}
#endif
static lfs_stag_t lfs_dir_fetchmatch(lfs_t *lfs,
lfs_mdir_t *dir, const lfs_block_t pair[2],
lfs_tag_t fmask, lfs_tag_t ftag, uint16_t *id,
int (*cb)(void *data, lfs_tag_t tag, const void *buffer), void *data) {
// we can find tag very efficiently during a fetch, since we're already
// scanning the entire directory
lfs_stag_t besttag = -1;
// if either block address is invalid we return LFS_ERR_CORRUPT here,
// otherwise later writes to the pair could fail
if (lfs->block_count
&& (pair[0] >= lfs->block_count || pair[1] >= lfs->block_count)) {
return LFS_ERR_CORRUPT;
}
// find the block with the most recent revision
uint32_t revs[2] = {0, 0};
int r = 0;
for (int i = 0; i < 2; i++) {
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, sizeof(revs[i]),
pair[i], 0, &revs[i], sizeof(revs[i]));
revs[i] = lfs_fromle32(revs[i]);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
if (err != LFS_ERR_CORRUPT &&
lfs_scmp(revs[i], revs[(i+1)%2]) > 0) {
r = i;
}
}
dir->pair[0] = pair[(r+0)%2];
dir->pair[1] = pair[(r+1)%2];
dir->rev = revs[(r+0)%2];
dir->off = 0; // nonzero = found some commits
// now scan tags to fetch the actual dir and find possible match
for (int i = 0; i < 2; i++) {
lfs_off_t off = 0;
lfs_tag_t ptag = 0xffffffff;
uint16_t tempcount = 0;
lfs_block_t temptail[2] = {LFS_BLOCK_NULL, LFS_BLOCK_NULL};
bool tempsplit = false;
lfs_stag_t tempbesttag = besttag;
// assume not erased until proven otherwise
bool maybeerased = false;
bool hasfcrc = false;
struct lfs_fcrc fcrc;
dir->rev = lfs_tole32(dir->rev);
uint32_t crc = lfs_crc(0xffffffff, &dir->rev, sizeof(dir->rev));
dir->rev = lfs_fromle32(dir->rev);
while (true) {
// extract next tag
lfs_tag_t tag;
off += lfs_tag_dsize(ptag);
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off, &tag, sizeof(tag));
if (err) {
if (err == LFS_ERR_CORRUPT) {
// can't continue?
break;
}
return err;
}
crc = lfs_crc(crc, &tag, sizeof(tag));
tag = lfs_frombe32(tag) ^ ptag;
// next commit not yet programmed?
if (!lfs_tag_isvalid(tag)) {
// we only might be erased if the last tag was a crc
maybeerased = (lfs_tag_type2(ptag) == LFS_TYPE_CCRC);
break;
// out of range?
} else if (off + lfs_tag_dsize(tag) > lfs->cfg->block_size) {
break;
}
ptag = tag;
if (lfs_tag_type2(tag) == LFS_TYPE_CCRC) {
// check the crc attr
uint32_t dcrc;
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag), &dcrc, sizeof(dcrc));
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
return err;
}
dcrc = lfs_fromle32(dcrc);
if (crc != dcrc) {
break;
}
// reset the next bit if we need to
ptag ^= (lfs_tag_t)(lfs_tag_chunk(tag) & 1U) << 31;
// toss our crc into the filesystem seed for
// pseudorandom numbers, note we use another crc here
// as a collection function because it is sufficiently
// random and convenient
lfs->seed = lfs_crc(lfs->seed, &crc, sizeof(crc));
// update with what's found so far
besttag = tempbesttag;
dir->off = off + lfs_tag_dsize(tag);
dir->etag = ptag;
dir->count = tempcount;
dir->tail[0] = temptail[0];
dir->tail[1] = temptail[1];
dir->split = tempsplit;
// reset crc, hasfcrc
crc = 0xffffffff;
continue;
}
// crc the entry first, hopefully leaving it in the cache
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag),
lfs_tag_dsize(tag)-sizeof(tag), &crc);
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
return err;
}
// directory modification tags?
if (lfs_tag_type1(tag) == LFS_TYPE_NAME) {
// increase count of files if necessary
if (lfs_tag_id(tag) >= tempcount) {
tempcount = lfs_tag_id(tag) + 1;
}
} else if (lfs_tag_type1(tag) == LFS_TYPE_SPLICE) {
tempcount += lfs_tag_splice(tag);
if (tag == (LFS_MKTAG(LFS_TYPE_DELETE, 0, 0) |
(LFS_MKTAG(0, 0x3ff, 0) & tempbesttag))) {
tempbesttag |= 0x80000000;
} else if (tempbesttag != -1 &&
lfs_tag_id(tag) <= lfs_tag_id(tempbesttag)) {
tempbesttag += LFS_MKTAG(0, lfs_tag_splice(tag), 0);
}
} else if (lfs_tag_type1(tag) == LFS_TYPE_TAIL) {
tempsplit = (lfs_tag_chunk(tag) & 1);
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag), &temptail, 8);
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
return err;
}
lfs_pair_fromle32(temptail);
} else if (lfs_tag_type3(tag) == LFS_TYPE_FCRC) {
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], off+sizeof(tag),
&fcrc, sizeof(fcrc));
if (err) {
if (err == LFS_ERR_CORRUPT) {
break;
}
return err;
}
lfs_fcrc_fromle32(&fcrc);
hasfcrc = true;
}
// found a match for our fetcher?
if ((fmask & tag) == (fmask & ftag)) {
int res = cb(data, tag, &(struct lfs_diskoff){
dir->pair[0], off+sizeof(tag)});
if (res < 0) {
if (res == LFS_ERR_CORRUPT) {
break;
}
return res;
}
if (res == LFS_CMP_EQ) {
// found a match
tempbesttag = tag;
} else if ((LFS_MKTAG(0x7ff, 0x3ff, 0) & tag) ==
(LFS_MKTAG(0x7ff, 0x3ff, 0) & tempbesttag)) {
// found an identical tag, but contents didn't match
// this must mean that our besttag has been overwritten
tempbesttag = -1;
} else if (res == LFS_CMP_GT &&
lfs_tag_id(tag) <= lfs_tag_id(tempbesttag)) {
// found a greater match, keep track to keep things sorted
tempbesttag = tag | 0x80000000;
}
}
}
// found no valid commits?
if (dir->off == 0) {
// try the other block?
lfs_pair_swap(dir->pair);
dir->rev = revs[(r+1)%2];
continue;
}
// did we end on a valid commit? we may have an erased block
dir->erased = false;
if (maybeerased && dir->off % lfs->cfg->prog_size == 0) {
#ifdef LFS_MULTIVERSION
// note versions < lfs2.1 did not have fcrc tags, if
// we're < lfs2.1 treat missing fcrc as erased data
//
// we don't strictly need to do this, but otherwise writing
// to lfs2.0 disks becomes very inefficient
if (lfs_fs_disk_version(lfs) < 0x00020001) {
dir->erased = true;
} else
#endif
if (hasfcrc) {
// check for an fcrc matching the next prog's erased state, if
// this failed most likely a previous prog was interrupted, we
// need a new erase
uint32_t fcrc_ = 0xffffffff;
int err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->block_size,
dir->pair[0], dir->off, fcrc.size, &fcrc_);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
// found beginning of erased part?
dir->erased = (fcrc_ == fcrc.crc);
}
}
// synthetic move
if (lfs_gstate_hasmovehere(&lfs->gdisk, dir->pair)) {
if (lfs_tag_id(lfs->gdisk.tag) == lfs_tag_id(besttag)) {
besttag |= 0x80000000;
} else if (besttag != -1 &&
lfs_tag_id(lfs->gdisk.tag) < lfs_tag_id(besttag)) {
besttag -= LFS_MKTAG(0, 1, 0);
}
}
// found tag? or found best id?
if (id) {
*id = lfs_min(lfs_tag_id(besttag), dir->count);
}
if (lfs_tag_isvalid(besttag)) {
return besttag;
} else if (lfs_tag_id(besttag) < dir->count) {
return LFS_ERR_NOENT;
} else {
return 0;
}
}
LFS_ERROR("Corrupted dir pair at {0x%"PRIx32", 0x%"PRIx32"}",
dir->pair[0], dir->pair[1]);
return LFS_ERR_CORRUPT;
}
static int lfs_dir_fetch(lfs_t *lfs,
lfs_mdir_t *dir, const lfs_block_t pair[2]) {
// note, mask=-1, tag=-1 can never match a tag since this
// pattern has the invalid bit set
return (int)lfs_dir_fetchmatch(lfs, dir, pair,
(lfs_tag_t)-1, (lfs_tag_t)-1, NULL, NULL, NULL);
}
static int lfs_dir_getgstate(lfs_t *lfs, const lfs_mdir_t *dir,
lfs_gstate_t *gstate) {
lfs_gstate_t temp;
lfs_stag_t res = lfs_dir_get(lfs, dir, LFS_MKTAG(0x7ff, 0, 0),
LFS_MKTAG(LFS_TYPE_MOVESTATE, 0, sizeof(temp)), &temp);
if (res < 0 && res != LFS_ERR_NOENT) {
return res;
}
if (res != LFS_ERR_NOENT) {
// xor together to find resulting gstate
lfs_gstate_fromle32(&temp);
lfs_gstate_xor(gstate, &temp);
}
return 0;
}
static int lfs_dir_getinfo(lfs_t *lfs, lfs_mdir_t *dir,
uint16_t id, struct lfs_info *info) {
if (id == 0x3ff) {
// special case for root
strcpy(info->name, "/");
info->type = LFS_TYPE_DIR;
return 0;
}
lfs_stag_t tag = lfs_dir_get(lfs, dir, LFS_MKTAG(0x780, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_NAME, id, lfs->name_max+1), info->name);
if (tag < 0) {
return (int)tag;
}
info->type = lfs_tag_type3(tag);
struct lfs_ctz ctz;
tag = lfs_dir_get(lfs, dir, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, id, sizeof(ctz)), &ctz);
if (tag < 0) {
return (int)tag;
}
lfs_ctz_fromle32(&ctz);
if (lfs_tag_type3(tag) == LFS_TYPE_CTZSTRUCT) {
info->size = ctz.size;
} else if (lfs_tag_type3(tag) == LFS_TYPE_INLINESTRUCT) {
info->size = lfs_tag_size(tag);
}
return 0;
}
struct lfs_dir_find_match {
lfs_t *lfs;
const void *name;
lfs_size_t size;
};
static int lfs_dir_find_match(void *data,
lfs_tag_t tag, const void *buffer) {
struct lfs_dir_find_match *name = data;
lfs_t *lfs = name->lfs;
const struct lfs_diskoff *disk = buffer;
// compare with disk
lfs_size_t diff = lfs_min(name->size, lfs_tag_size(tag));
int res = lfs_bd_cmp(lfs,
NULL, &lfs->rcache, diff,
disk->block, disk->off, name->name, diff);
if (res != LFS_CMP_EQ) {
return res;
}
// only equal if our size is still the same
if (name->size != lfs_tag_size(tag)) {
return (name->size < lfs_tag_size(tag)) ? LFS_CMP_LT : LFS_CMP_GT;
}
// found a match!
return LFS_CMP_EQ;
}
// lfs_dir_find tries to set path and id even if file is not found
//
// returns:
// - 0 if file is found
// - LFS_ERR_NOENT if file or parent is not found
// - LFS_ERR_NOTDIR if parent is not a dir
static lfs_stag_t lfs_dir_find(lfs_t *lfs, lfs_mdir_t *dir,
const char **path, uint16_t *id) {
// we reduce path to a single name if we can find it
const char *name = *path;
// default to root dir
lfs_stag_t tag = LFS_MKTAG(LFS_TYPE_DIR, 0x3ff, 0);
dir->tail[0] = lfs->root[0];
dir->tail[1] = lfs->root[1];
// empty paths are not allowed
if (*name == '\0') {
return LFS_ERR_INVAL;
}
while (true) {
nextname:
// skip slashes if we're a directory
if (lfs_tag_type3(tag) == LFS_TYPE_DIR) {
name += strspn(name, "/");
}
lfs_size_t namelen = strcspn(name, "/");
// skip '.'
if (namelen == 1 && memcmp(name, ".", 1) == 0) {
name += namelen;
goto nextname;
}
// error on unmatched '..', trying to go above root?
if (namelen == 2 && memcmp(name, "..", 2) == 0) {
return LFS_ERR_INVAL;
}
// skip if matched by '..' in name
const char *suffix = name + namelen;
lfs_size_t sufflen;
int depth = 1;
while (true) {
suffix += strspn(suffix, "/");
sufflen = strcspn(suffix, "/");
if (sufflen == 0) {
break;
}
if (sufflen == 1 && memcmp(suffix, ".", 1) == 0) {
// noop
} else if (sufflen == 2 && memcmp(suffix, "..", 2) == 0) {
depth -= 1;
if (depth == 0) {
name = suffix + sufflen;
goto nextname;
}
} else {
depth += 1;
}
suffix += sufflen;
}
// found path
if (*name == '\0') {
return tag;
}
// update what we've found so far
*path = name;
// only continue if we're a directory
if (lfs_tag_type3(tag) != LFS_TYPE_DIR) {
return LFS_ERR_NOTDIR;
}
// grab the entry data
if (lfs_tag_id(tag) != 0x3ff) {
lfs_stag_t res = lfs_dir_get(lfs, dir, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, lfs_tag_id(tag), 8), dir->tail);
if (res < 0) {
return res;
}
lfs_pair_fromle32(dir->tail);
}
// find entry matching name
while (true) {
tag = lfs_dir_fetchmatch(lfs, dir, dir->tail,
LFS_MKTAG(0x780, 0, 0),
LFS_MKTAG(LFS_TYPE_NAME, 0, namelen),
id,
lfs_dir_find_match, &(struct lfs_dir_find_match){
lfs, name, namelen});
if (tag < 0) {
return tag;
}
if (tag) {
break;
}
if (!dir->split) {
return LFS_ERR_NOENT;
}
}
// to next name
name += namelen;
}
}
// commit logic
struct lfs_commit {
lfs_block_t block;
lfs_off_t off;
lfs_tag_t ptag;
uint32_t crc;
lfs_off_t begin;
lfs_off_t end;
};
#ifndef LFS_READONLY
static int lfs_dir_commitprog(lfs_t *lfs, struct lfs_commit *commit,
const void *buffer, lfs_size_t size) {
int err = lfs_bd_prog(lfs,
&lfs->pcache, &lfs->rcache, false,
commit->block, commit->off ,
(const uint8_t*)buffer, size);
if (err) {
return err;
}
commit->crc = lfs_crc(commit->crc, buffer, size);
commit->off += size;
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_commitattr(lfs_t *lfs, struct lfs_commit *commit,
lfs_tag_t tag, const void *buffer) {
// check if we fit
lfs_size_t dsize = lfs_tag_dsize(tag);
if (commit->off + dsize > commit->end) {
return LFS_ERR_NOSPC;
}
// write out tag
lfs_tag_t ntag = lfs_tobe32((tag & 0x7fffffff) ^ commit->ptag);
int err = lfs_dir_commitprog(lfs, commit, &ntag, sizeof(ntag));
if (err) {
return err;
}
if (!(tag & 0x80000000)) {
// from memory
err = lfs_dir_commitprog(lfs, commit, buffer, dsize-sizeof(tag));
if (err) {
return err;
}
} else {
// from disk
const struct lfs_diskoff *disk = buffer;
for (lfs_off_t i = 0; i < dsize-sizeof(tag); i++) {
// rely on caching to make this efficient
uint8_t dat;
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, dsize-sizeof(tag)-i,
disk->block, disk->off+i, &dat, 1);
if (err) {
return err;
}
err = lfs_dir_commitprog(lfs, commit, &dat, 1);
if (err) {
return err;
}
}
}
commit->ptag = tag & 0x7fffffff;
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_commitcrc(lfs_t *lfs, struct lfs_commit *commit) {
// align to program units
//
// this gets a bit complex as we have two types of crcs:
// - 5-word crc with fcrc to check following prog (middle of block)
// - 2-word crc with no following prog (end of block)
const lfs_off_t end = lfs_alignup(
lfs_min(commit->off + 5*sizeof(uint32_t), lfs->cfg->block_size),
lfs->cfg->prog_size);
lfs_off_t off1 = 0;
uint32_t crc1 = 0;
// create crc tags to fill up remainder of commit, note that
// padding is not crced, which lets fetches skip padding but
// makes committing a bit more complicated
while (commit->off < end) {
lfs_off_t noff = (
lfs_min(end - (commit->off+sizeof(lfs_tag_t)), 0x3fe)
+ (commit->off+sizeof(lfs_tag_t)));
// too large for crc tag? need padding commits
if (noff < end) {
noff = lfs_min(noff, end - 5*sizeof(uint32_t));
}
// space for fcrc?
uint8_t eperturb = (uint8_t)-1;
if (noff >= end && noff <= lfs->cfg->block_size - lfs->cfg->prog_size) {
// first read the leading byte, this always contains a bit
// we can perturb to avoid writes that don't change the fcrc
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, lfs->cfg->prog_size,
commit->block, noff, &eperturb, 1);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
#ifdef LFS_MULTIVERSION
// unfortunately fcrcs break mdir fetching < lfs2.1, so only write
// these if we're a >= lfs2.1 filesystem
if (lfs_fs_disk_version(lfs) <= 0x00020000) {
// don't write fcrc
} else
#endif
{
// find the expected fcrc, don't bother avoiding a reread
// of the eperturb, it should still be in our cache
struct lfs_fcrc fcrc = {
.size = lfs->cfg->prog_size,
.crc = 0xffffffff
};
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, lfs->cfg->prog_size,
commit->block, noff, fcrc.size, &fcrc.crc);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
lfs_fcrc_tole32(&fcrc);
err = lfs_dir_commitattr(lfs, commit,
LFS_MKTAG(LFS_TYPE_FCRC, 0x3ff, sizeof(struct lfs_fcrc)),
&fcrc);
if (err) {
return err;
}
}
}
// build commit crc
struct {
lfs_tag_t tag;
uint32_t crc;
} ccrc;
lfs_tag_t ntag = LFS_MKTAG(
LFS_TYPE_CCRC + (((uint8_t)~eperturb) >> 7), 0x3ff,
noff - (commit->off+sizeof(lfs_tag_t)));
ccrc.tag = lfs_tobe32(ntag ^ commit->ptag);
commit->crc = lfs_crc(commit->crc, &ccrc.tag, sizeof(lfs_tag_t));
ccrc.crc = lfs_tole32(commit->crc);
int err = lfs_bd_prog(lfs,
&lfs->pcache, &lfs->rcache, false,
commit->block, commit->off, &ccrc, sizeof(ccrc));
if (err) {
return err;
}
// keep track of non-padding checksum to verify
if (off1 == 0) {
off1 = commit->off + sizeof(lfs_tag_t);
crc1 = commit->crc;
}
commit->off = noff;
// perturb valid bit?
commit->ptag = ntag ^ ((0x80UL & ~eperturb) << 24);
// reset crc for next commit
commit->crc = 0xffffffff;
// manually flush here since we don't prog the padding, this confuses
// the caching layer
if (noff >= end || noff >= lfs->pcache.off + lfs->cfg->cache_size) {
// flush buffers
int err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false);
if (err) {
return err;
}
}
}
// successful commit, check checksums to make sure
//
// note that we don't need to check padding commits, worst
// case if they are corrupted we would have had to compact anyways
lfs_off_t off = commit->begin;
uint32_t crc = 0xffffffff;
int err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, off1+sizeof(uint32_t),
commit->block, off, off1-off, &crc);
if (err) {
return err;
}
// check non-padding commits against known crc
if (crc != crc1) {
return LFS_ERR_CORRUPT;
}
// make sure to check crc in case we happen to pick
// up an unrelated crc (frozen block?)
err = lfs_bd_crc(lfs,
NULL, &lfs->rcache, sizeof(uint32_t),
commit->block, off1, sizeof(uint32_t), &crc);
if (err) {
return err;
}
if (crc != 0) {
return LFS_ERR_CORRUPT;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_alloc(lfs_t *lfs, lfs_mdir_t *dir) {
// allocate pair of dir blocks (backwards, so we write block 1 first)
for (int i = 0; i < 2; i++) {
int err = lfs_alloc(lfs, &dir->pair[(i+1)%2]);
if (err) {
return err;
}
}
// zero for reproducibility in case initial block is unreadable
dir->rev = 0;
// rather than clobbering one of the blocks we just pretend
// the revision may be valid
int err = lfs_bd_read(lfs,
NULL, &lfs->rcache, sizeof(dir->rev),
dir->pair[0], 0, &dir->rev, sizeof(dir->rev));
dir->rev = lfs_fromle32(dir->rev);
if (err && err != LFS_ERR_CORRUPT) {
return err;
}
// to make sure we don't immediately evict, align the new revision count
// to our block_cycles modulus, see lfs_dir_compact for why our modulus
// is tweaked this way
if (lfs->cfg->block_cycles > 0) {
dir->rev = lfs_alignup(dir->rev, ((lfs->cfg->block_cycles+1)|1));
}
// set defaults
dir->off = sizeof(dir->rev);
dir->etag = 0xffffffff;
dir->count = 0;
dir->tail[0] = LFS_BLOCK_NULL;
dir->tail[1] = LFS_BLOCK_NULL;
dir->erased = false;
dir->split = false;
// don't write out yet, let caller take care of that
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_drop(lfs_t *lfs, lfs_mdir_t *dir, lfs_mdir_t *tail) {
// steal state
int err = lfs_dir_getgstate(lfs, tail, &lfs->gdelta);
if (err) {
return err;
}
// steal tail
lfs_pair_tole32(tail->tail);
err = lfs_dir_commit(lfs, dir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_TAIL + tail->split, 0x3ff, 8), tail->tail}));
lfs_pair_fromle32(tail->tail);
if (err) {
return err;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_split(lfs_t *lfs,
lfs_mdir_t *dir, const struct lfs_mattr *attrs, int attrcount,
lfs_mdir_t *source, uint16_t split, uint16_t end) {
// create tail metadata pair
lfs_mdir_t tail;
int err = lfs_dir_alloc(lfs, &tail);
if (err) {
return err;
}
tail.split = dir->split;
tail.tail[0] = dir->tail[0];
tail.tail[1] = dir->tail[1];
// note we don't care about LFS_OK_RELOCATED
int res = lfs_dir_compact(lfs, &tail, attrs, attrcount, source, split, end);
if (res < 0) {
return res;
}
dir->tail[0] = tail.pair[0];
dir->tail[1] = tail.pair[1];
dir->split = true;
// update root if needed
if (lfs_pair_cmp(dir->pair, lfs->root) == 0 && split == 0) {
lfs->root[0] = tail.pair[0];
lfs->root[1] = tail.pair[1];
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_commit_size(void *p, lfs_tag_t tag, const void *buffer) {
lfs_size_t *size = p;
(void)buffer;
*size += lfs_tag_dsize(tag);
return 0;
}
#endif
#ifndef LFS_READONLY
struct lfs_dir_commit_commit {
lfs_t *lfs;
struct lfs_commit *commit;
};
#endif
#ifndef LFS_READONLY
static int lfs_dir_commit_commit(void *p, lfs_tag_t tag, const void *buffer) {
struct lfs_dir_commit_commit *commit = p;
return lfs_dir_commitattr(commit->lfs, commit->commit, tag, buffer);
}
#endif
#ifndef LFS_READONLY
static bool lfs_dir_needsrelocation(lfs_t *lfs, lfs_mdir_t *dir) {
// If our revision count == n * block_cycles, we should force a relocation,
// this is how littlefs wear-levels at the metadata-pair level. Note that we
// actually use (block_cycles+1)|1, this is to avoid two corner cases:
// 1. block_cycles = 1, which would prevent relocations from terminating
// 2. block_cycles = 2n, which, due to aliasing, would only ever relocate
// one metadata block in the pair, effectively making this useless
return (lfs->cfg->block_cycles > 0
&& ((dir->rev + 1) % ((lfs->cfg->block_cycles+1)|1) == 0));
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_compact(lfs_t *lfs,
lfs_mdir_t *dir, const struct lfs_mattr *attrs, int attrcount,
lfs_mdir_t *source, uint16_t begin, uint16_t end) {
// save some state in case block is bad
bool relocated = false;
bool tired = lfs_dir_needsrelocation(lfs, dir);
// increment revision count
dir->rev += 1;
// do not proactively relocate blocks during migrations, this
// can cause a number of failure states such: clobbering the
// v1 superblock if we relocate root, and invalidating directory
// pointers if we relocate the head of a directory. On top of
// this, relocations increase the overall complexity of
// lfs_migration, which is already a delicate operation.
#ifdef LFS_MIGRATE
if (lfs->lfs1) {
tired = false;
}
#endif
if (tired && lfs_pair_cmp(dir->pair, (const lfs_block_t[2]){0, 1}) != 0) {
// we're writing too much, time to relocate
goto relocate;
}
// begin loop to commit compaction to blocks until a compact sticks
while (true) {
{
// setup commit state
struct lfs_commit commit = {
.block = dir->pair[1],
.off = 0,
.ptag = 0xffffffff,
.crc = 0xffffffff,
.begin = 0,
.end = (lfs->cfg->metadata_max ?
lfs->cfg->metadata_max : lfs->cfg->block_size) - 8,
};
// erase block to write to
int err = lfs_bd_erase(lfs, dir->pair[1]);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
// write out header
dir->rev = lfs_tole32(dir->rev);
err = lfs_dir_commitprog(lfs, &commit,
&dir->rev, sizeof(dir->rev));
dir->rev = lfs_fromle32(dir->rev);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
// traverse the directory, this time writing out all unique tags
err = lfs_dir_traverse(lfs,
source, 0, 0xffffffff, attrs, attrcount,
LFS_MKTAG(0x400, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_NAME, 0, 0),
begin, end, -begin,
lfs_dir_commit_commit, &(struct lfs_dir_commit_commit){
lfs, &commit});
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
// commit tail, which may be new after last size check
if (!lfs_pair_isnull(dir->tail)) {
lfs_pair_tole32(dir->tail);
err = lfs_dir_commitattr(lfs, &commit,
LFS_MKTAG(LFS_TYPE_TAIL + dir->split, 0x3ff, 8),
dir->tail);
lfs_pair_fromle32(dir->tail);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
}
// bring over gstate?
lfs_gstate_t delta = {0};
if (!relocated) {
lfs_gstate_xor(&delta, &lfs->gdisk);
lfs_gstate_xor(&delta, &lfs->gstate);
}
lfs_gstate_xor(&delta, &lfs->gdelta);
delta.tag &= ~LFS_MKTAG(0, 0, 0x3ff);
err = lfs_dir_getgstate(lfs, dir, &delta);
if (err) {
return err;
}
if (!lfs_gstate_iszero(&delta)) {
lfs_gstate_tole32(&delta);
err = lfs_dir_commitattr(lfs, &commit,
LFS_MKTAG(LFS_TYPE_MOVESTATE, 0x3ff,
sizeof(delta)), &delta);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
}
// complete commit with crc
err = lfs_dir_commitcrc(lfs, &commit);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
// successful compaction, swap dir pair to indicate most recent
LFS_ASSERT(commit.off % lfs->cfg->prog_size == 0);
lfs_pair_swap(dir->pair);
dir->count = end - begin;
dir->off = commit.off;
dir->etag = commit.ptag;
// update gstate
lfs->gdelta = (lfs_gstate_t){0};
if (!relocated) {
lfs->gdisk = lfs->gstate;
}
}
break;
relocate:
// commit was corrupted, drop caches and prepare to relocate block
relocated = true;
lfs_cache_drop(lfs, &lfs->pcache);
if (!tired) {
LFS_DEBUG("Bad block at 0x%"PRIx32, dir->pair[1]);
}
// can't relocate superblock, filesystem is now frozen
if (lfs_pair_cmp(dir->pair, (const lfs_block_t[2]){0, 1}) == 0) {
LFS_WARN("Superblock 0x%"PRIx32" has become unwritable",
dir->pair[1]);
return LFS_ERR_NOSPC;
}
// relocate half of pair
int err = lfs_alloc(lfs, &dir->pair[1]);
if (err && (err != LFS_ERR_NOSPC || !tired)) {
return err;
}
tired = false;
continue;
}
return relocated ? LFS_OK_RELOCATED : 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_splittingcompact(lfs_t *lfs, lfs_mdir_t *dir,
const struct lfs_mattr *attrs, int attrcount,
lfs_mdir_t *source, uint16_t begin, uint16_t end) {
while (true) {
// find size of first split, we do this by halving the split until
// the metadata is guaranteed to fit
//
// Note that this isn't a true binary search, we never increase the
// split size. This may result in poorly distributed metadata but isn't
// worth the extra code size or performance hit to fix.
lfs_size_t split = begin;
while (end - split > 1) {
lfs_size_t size = 0;
int err = lfs_dir_traverse(lfs,
source, 0, 0xffffffff, attrs, attrcount,
LFS_MKTAG(0x400, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_NAME, 0, 0),
split, end, -split,
lfs_dir_commit_size, &size);
if (err) {
return err;
}
// space is complicated, we need room for:
//
// - tail: 4+2*4 = 12 bytes
// - gstate: 4+3*4 = 16 bytes
// - move delete: 4 = 4 bytes
// - crc: 4+4 = 8 bytes
// total = 40 bytes
//
// And we cap at half a block to avoid degenerate cases with
// nearly-full metadata blocks.
//
lfs_size_t metadata_max = (lfs->cfg->metadata_max)
? lfs->cfg->metadata_max
: lfs->cfg->block_size;
if (end - split < 0xff
&& size <= lfs_min(
metadata_max - 40,
lfs_alignup(
metadata_max/2,
lfs->cfg->prog_size))) {
break;
}
split = split + ((end - split) / 2);
}
if (split == begin) {
// no split needed
break;
}
// split into two metadata pairs and continue
int err = lfs_dir_split(lfs, dir, attrs, attrcount,
source, split, end);
if (err && err != LFS_ERR_NOSPC) {
return err;
}
if (err) {
// we can't allocate a new block, try to compact with degraded
// performance
LFS_WARN("Unable to split {0x%"PRIx32", 0x%"PRIx32"}",
dir->pair[0], dir->pair[1]);
break;
} else {
end = split;
}
}
if (lfs_dir_needsrelocation(lfs, dir)
&& lfs_pair_cmp(dir->pair, (const lfs_block_t[2]){0, 1}) == 0) {
// oh no! we're writing too much to the superblock,
// should we expand?
lfs_ssize_t size = lfs_fs_size_(lfs);
if (size < 0) {
return size;
}
// littlefs cannot reclaim expanded superblocks, so expand cautiously
//
// if our filesystem is more than ~88% full, don't expand, this is
// somewhat arbitrary
if (lfs->block_count - size > lfs->block_count/8) {
LFS_DEBUG("Expanding superblock at rev %"PRIu32, dir->rev);
int err = lfs_dir_split(lfs, dir, attrs, attrcount,
source, begin, end);
if (err && err != LFS_ERR_NOSPC) {
return err;
}
if (err) {
// welp, we tried, if we ran out of space there's not much
// we can do, we'll error later if we've become frozen
LFS_WARN("Unable to expand superblock");
} else {
// duplicate the superblock entry into the new superblock
end = 1;
}
}
}
return lfs_dir_compact(lfs, dir, attrs, attrcount, source, begin, end);
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_relocatingcommit(lfs_t *lfs, lfs_mdir_t *dir,
const lfs_block_t pair[2],
const struct lfs_mattr *attrs, int attrcount,
lfs_mdir_t *pdir) {
int state = 0;
// calculate changes to the directory
bool hasdelete = false;
for (int i = 0; i < attrcount; i++) {
if (lfs_tag_type3(attrs[i].tag) == LFS_TYPE_CREATE) {
dir->count += 1;
} else if (lfs_tag_type3(attrs[i].tag) == LFS_TYPE_DELETE) {
LFS_ASSERT(dir->count > 0);
dir->count -= 1;
hasdelete = true;
} else if (lfs_tag_type1(attrs[i].tag) == LFS_TYPE_TAIL) {
dir->tail[0] = ((lfs_block_t*)attrs[i].buffer)[0];
dir->tail[1] = ((lfs_block_t*)attrs[i].buffer)[1];
dir->split = (lfs_tag_chunk(attrs[i].tag) & 1);
lfs_pair_fromle32(dir->tail);
}
}
// should we actually drop the directory block?
if (hasdelete && dir->count == 0) {
LFS_ASSERT(pdir);
int err = lfs_fs_pred(lfs, dir->pair, pdir);
if (err && err != LFS_ERR_NOENT) {
return err;
}
if (err != LFS_ERR_NOENT && pdir->split) {
state = LFS_OK_DROPPED;
goto fixmlist;
}
}
if (dir->erased && dir->count < 0xff) {
// try to commit
struct lfs_commit commit = {
.block = dir->pair[0],
.off = dir->off,
.ptag = dir->etag,
.crc = 0xffffffff,
.begin = dir->off,
.end = (lfs->cfg->metadata_max ?
lfs->cfg->metadata_max : lfs->cfg->block_size) - 8,
};
// traverse attrs that need to be written out
lfs_pair_tole32(dir->tail);
int err = lfs_dir_traverse(lfs,
dir, dir->off, dir->etag, attrs, attrcount,
0, 0, 0, 0, 0,
lfs_dir_commit_commit, &(struct lfs_dir_commit_commit){
lfs, &commit});
lfs_pair_fromle32(dir->tail);
if (err) {
if (err == LFS_ERR_NOSPC || err == LFS_ERR_CORRUPT) {
goto compact;
}
return err;
}
// commit any global diffs if we have any
lfs_gstate_t delta = {0};
lfs_gstate_xor(&delta, &lfs->gstate);
lfs_gstate_xor(&delta, &lfs->gdisk);
lfs_gstate_xor(&delta, &lfs->gdelta);
delta.tag &= ~LFS_MKTAG(0, 0, 0x3ff);
if (!lfs_gstate_iszero(&delta)) {
err = lfs_dir_getgstate(lfs, dir, &delta);
if (err) {
return err;
}
lfs_gstate_tole32(&delta);
err = lfs_dir_commitattr(lfs, &commit,
LFS_MKTAG(LFS_TYPE_MOVESTATE, 0x3ff,
sizeof(delta)), &delta);
if (err) {
if (err == LFS_ERR_NOSPC || err == LFS_ERR_CORRUPT) {
goto compact;
}
return err;
}
}
// finalize commit with the crc
err = lfs_dir_commitcrc(lfs, &commit);
if (err) {
if (err == LFS_ERR_NOSPC || err == LFS_ERR_CORRUPT) {
goto compact;
}
return err;
}
// successful commit, update dir
LFS_ASSERT(commit.off % lfs->cfg->prog_size == 0);
dir->off = commit.off;
dir->etag = commit.ptag;
// and update gstate
lfs->gdisk = lfs->gstate;
lfs->gdelta = (lfs_gstate_t){0};
goto fixmlist;
}
compact:
// fall back to compaction
lfs_cache_drop(lfs, &lfs->pcache);
state = lfs_dir_splittingcompact(lfs, dir, attrs, attrcount,
dir, 0, dir->count);
if (state < 0) {
return state;
}
goto fixmlist;
fixmlist:;
// this complicated bit of logic is for fixing up any active
// metadata-pairs that we may have affected
//
// note we have to make two passes since the mdir passed to
// lfs_dir_commit could also be in this list, and even then
// we need to copy the pair so they don't get clobbered if we refetch
// our mdir.
lfs_block_t oldpair[2] = {pair[0], pair[1]};
for (struct lfs_mlist *d = lfs->mlist; d; d = d->next) {
if (lfs_pair_cmp(d->m.pair, oldpair) == 0) {
d->m = *dir;
if (d->m.pair != pair) {
for (int i = 0; i < attrcount; i++) {
if (lfs_tag_type3(attrs[i].tag) == LFS_TYPE_DELETE &&
d->id == lfs_tag_id(attrs[i].tag) &&
d->type != LFS_TYPE_DIR) {
d->m.pair[0] = LFS_BLOCK_NULL;
d->m.pair[1] = LFS_BLOCK_NULL;
} else if (lfs_tag_type3(attrs[i].tag) == LFS_TYPE_DELETE &&
d->id > lfs_tag_id(attrs[i].tag)) {
d->id -= 1;
if (d->type == LFS_TYPE_DIR) {
((lfs_dir_t*)d)->pos -= 1;
}
} else if (lfs_tag_type3(attrs[i].tag) == LFS_TYPE_CREATE &&
d->id >= lfs_tag_id(attrs[i].tag)) {
d->id += 1;
if (d->type == LFS_TYPE_DIR) {
((lfs_dir_t*)d)->pos += 1;
}
}
}
}
while (d->id >= d->m.count && d->m.split) {
// we split and id is on tail now
if (lfs_pair_cmp(d->m.tail, lfs->root) != 0) {
d->id -= d->m.count;
}
int err = lfs_dir_fetch(lfs, &d->m, d->m.tail);
if (err) {
return err;
}
}
}
}
return state;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_orphaningcommit(lfs_t *lfs, lfs_mdir_t *dir,
const struct lfs_mattr *attrs, int attrcount) {
// check for any inline files that aren't RAM backed and
// forcefully evict them, needed for filesystem consistency
for (lfs_file_t *f = (lfs_file_t*)lfs->mlist; f; f = f->next) {
if (dir != &f->m && lfs_pair_cmp(f->m.pair, dir->pair) == 0 &&
f->type == LFS_TYPE_REG && (f->flags & LFS_F_INLINE) &&
f->ctz.size > lfs->cfg->cache_size) {
int err = lfs_file_outline(lfs, f);
if (err) {
return err;
}
err = lfs_file_flush(lfs, f);
if (err) {
return err;
}
}
}
lfs_block_t lpair[2] = {dir->pair[0], dir->pair[1]};
lfs_mdir_t ldir = *dir;
lfs_mdir_t pdir;
int state = lfs_dir_relocatingcommit(lfs, &ldir, dir->pair,
attrs, attrcount, &pdir);
if (state < 0) {
return state;
}
// update if we're not in mlist, note we may have already been
// updated if we are in mlist
if (lfs_pair_cmp(dir->pair, lpair) == 0) {
*dir = ldir;
}
// commit was successful, but may require other changes in the
// filesystem, these would normally be tail recursive, but we have
// flattened them here avoid unbounded stack usage
// need to drop?
if (state == LFS_OK_DROPPED) {
// steal state
int err = lfs_dir_getgstate(lfs, dir, &lfs->gdelta);
if (err) {
return err;
}
// steal tail, note that this can't create a recursive drop
lpair[0] = pdir.pair[0];
lpair[1] = pdir.pair[1];
lfs_pair_tole32(dir->tail);
state = lfs_dir_relocatingcommit(lfs, &pdir, lpair, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_TAIL + dir->split, 0x3ff, 8),
dir->tail}),
NULL);
lfs_pair_fromle32(dir->tail);
if (state < 0) {
return state;
}
ldir = pdir;
}
// need to relocate?
bool orphans = false;
while (state == LFS_OK_RELOCATED) {
LFS_DEBUG("Relocating {0x%"PRIx32", 0x%"PRIx32"} "
"-> {0x%"PRIx32", 0x%"PRIx32"}",
lpair[0], lpair[1], ldir.pair[0], ldir.pair[1]);
state = 0;
// update internal root
if (lfs_pair_cmp(lpair, lfs->root) == 0) {
lfs->root[0] = ldir.pair[0];
lfs->root[1] = ldir.pair[1];
}
// update internally tracked dirs
for (struct lfs_mlist *d = lfs->mlist; d; d = d->next) {
if (lfs_pair_cmp(lpair, d->m.pair) == 0) {
d->m.pair[0] = ldir.pair[0];
d->m.pair[1] = ldir.pair[1];
}
if (d->type == LFS_TYPE_DIR &&
lfs_pair_cmp(lpair, ((lfs_dir_t*)d)->head) == 0) {
((lfs_dir_t*)d)->head[0] = ldir.pair[0];
((lfs_dir_t*)d)->head[1] = ldir.pair[1];
}
}
// find parent
lfs_stag_t tag = lfs_fs_parent(lfs, lpair, &pdir);
if (tag < 0 && tag != LFS_ERR_NOENT) {
return tag;
}
bool hasparent = (tag != LFS_ERR_NOENT);
if (tag != LFS_ERR_NOENT) {
// note that if we have a parent, we must have a pred, so this will
// always create an orphan
int err = lfs_fs_preporphans(lfs, +1);
if (err) {
return err;
}
// fix pending move in this pair? this looks like an optimization but
// is in fact _required_ since relocating may outdate the move.
uint16_t moveid = 0x3ff;
if (lfs_gstate_hasmovehere(&lfs->gstate, pdir.pair)) {
moveid = lfs_tag_id(lfs->gstate.tag);
LFS_DEBUG("Fixing move while relocating "
"{0x%"PRIx32", 0x%"PRIx32"} 0x%"PRIx16"\n",
pdir.pair[0], pdir.pair[1], moveid);
lfs_fs_prepmove(lfs, 0x3ff, NULL);
if (moveid < lfs_tag_id(tag)) {
tag -= LFS_MKTAG(0, 1, 0);
}
}
lfs_block_t ppair[2] = {pdir.pair[0], pdir.pair[1]};
lfs_pair_tole32(ldir.pair);
state = lfs_dir_relocatingcommit(lfs, &pdir, ppair, LFS_MKATTRS(
{LFS_MKTAG_IF(moveid != 0x3ff,
LFS_TYPE_DELETE, moveid, 0), NULL},
{tag, ldir.pair}),
NULL);
lfs_pair_fromle32(ldir.pair);
if (state < 0) {
return state;
}
if (state == LFS_OK_RELOCATED) {
lpair[0] = ppair[0];
lpair[1] = ppair[1];
ldir = pdir;
orphans = true;
continue;
}
}
// find pred
int err = lfs_fs_pred(lfs, lpair, &pdir);
if (err && err != LFS_ERR_NOENT) {
return err;
}
LFS_ASSERT(!(hasparent && err == LFS_ERR_NOENT));
// if we can't find dir, it must be new
if (err != LFS_ERR_NOENT) {
if (lfs_gstate_hasorphans(&lfs->gstate)) {
// next step, clean up orphans
err = lfs_fs_preporphans(lfs, -(int8_t)hasparent);
if (err) {
return err;
}
}
// fix pending move in this pair? this looks like an optimization
// but is in fact _required_ since relocating may outdate the move.
uint16_t moveid = 0x3ff;
if (lfs_gstate_hasmovehere(&lfs->gstate, pdir.pair)) {
moveid = lfs_tag_id(lfs->gstate.tag);
LFS_DEBUG("Fixing move while relocating "
"{0x%"PRIx32", 0x%"PRIx32"} 0x%"PRIx16"\n",
pdir.pair[0], pdir.pair[1], moveid);
lfs_fs_prepmove(lfs, 0x3ff, NULL);
}
// replace bad pair, either we clean up desync, or no desync occured
lpair[0] = pdir.pair[0];
lpair[1] = pdir.pair[1];
lfs_pair_tole32(ldir.pair);
state = lfs_dir_relocatingcommit(lfs, &pdir, lpair, LFS_MKATTRS(
{LFS_MKTAG_IF(moveid != 0x3ff,
LFS_TYPE_DELETE, moveid, 0), NULL},
{LFS_MKTAG(LFS_TYPE_TAIL + pdir.split, 0x3ff, 8),
ldir.pair}),
NULL);
lfs_pair_fromle32(ldir.pair);
if (state < 0) {
return state;
}
ldir = pdir;
}
}
return orphans ? LFS_OK_ORPHANED : 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_dir_commit(lfs_t *lfs, lfs_mdir_t *dir,
const struct lfs_mattr *attrs, int attrcount) {
int orphans = lfs_dir_orphaningcommit(lfs, dir, attrs, attrcount);
if (orphans < 0) {
return orphans;
}
if (orphans) {
// make sure we've removed all orphans, this is a noop if there
// are none, but if we had nested blocks failures we may have
// created some
int err = lfs_fs_deorphan(lfs, false);
if (err) {
return err;
}
}
return 0;
}
#endif
/// Top level directory operations ///
#ifndef LFS_READONLY
static int lfs_mkdir_(lfs_t *lfs, const char *path) {
// deorphan if we haven't yet, needed at most once after poweron
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
struct lfs_mlist cwd;
cwd.next = lfs->mlist;
uint16_t id;
err = lfs_dir_find(lfs, &cwd.m, &path, &id);
if (!(err == LFS_ERR_NOENT && lfs_path_islast(path))) {
return (err < 0) ? err : LFS_ERR_EXIST;
}
// check that name fits
lfs_size_t nlen = lfs_path_namelen(path);
if (nlen > lfs->name_max) {
return LFS_ERR_NAMETOOLONG;
}
// build up new directory
lfs_alloc_ckpoint(lfs);
lfs_mdir_t dir;
err = lfs_dir_alloc(lfs, &dir);
if (err) {
return err;
}
// find end of list
lfs_mdir_t pred = cwd.m;
while (pred.split) {
err = lfs_dir_fetch(lfs, &pred, pred.tail);
if (err) {
return err;
}
}
// setup dir
lfs_pair_tole32(pred.tail);
err = lfs_dir_commit(lfs, &dir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_SOFTTAIL, 0x3ff, 8), pred.tail}));
lfs_pair_fromle32(pred.tail);
if (err) {
return err;
}
// current block not end of list?
if (cwd.m.split) {
// update tails, this creates a desync
err = lfs_fs_preporphans(lfs, +1);
if (err) {
return err;
}
// it's possible our predecessor has to be relocated, and if
// our parent is our predecessor's predecessor, this could have
// caused our parent to go out of date, fortunately we can hook
// ourselves into littlefs to catch this
cwd.type = 0;
cwd.id = 0;
lfs->mlist = &cwd;
lfs_pair_tole32(dir.pair);
err = lfs_dir_commit(lfs, &pred, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_SOFTTAIL, 0x3ff, 8), dir.pair}));
lfs_pair_fromle32(dir.pair);
if (err) {
lfs->mlist = cwd.next;
return err;
}
lfs->mlist = cwd.next;
err = lfs_fs_preporphans(lfs, -1);
if (err) {
return err;
}
}
// now insert into our parent block
lfs_pair_tole32(dir.pair);
err = lfs_dir_commit(lfs, &cwd.m, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_CREATE, id, 0), NULL},
{LFS_MKTAG(LFS_TYPE_DIR, id, nlen), path},
{LFS_MKTAG(LFS_TYPE_DIRSTRUCT, id, 8), dir.pair},
{LFS_MKTAG_IF(!cwd.m.split,
LFS_TYPE_SOFTTAIL, 0x3ff, 8), dir.pair}));
lfs_pair_fromle32(dir.pair);
if (err) {
return err;
}
return 0;
}
#endif
static int lfs_dir_open_(lfs_t *lfs, lfs_dir_t *dir, const char *path) {
lfs_stag_t tag = lfs_dir_find(lfs, &dir->m, &path, NULL);
if (tag < 0) {
return tag;
}
if (lfs_tag_type3(tag) != LFS_TYPE_DIR) {
return LFS_ERR_NOTDIR;
}
lfs_block_t pair[2];
if (lfs_tag_id(tag) == 0x3ff) {
// handle root dir separately
pair[0] = lfs->root[0];
pair[1] = lfs->root[1];
} else {
// get dir pair from parent
lfs_stag_t res = lfs_dir_get(lfs, &dir->m, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, lfs_tag_id(tag), 8), pair);
if (res < 0) {
return res;
}
lfs_pair_fromle32(pair);
}
// fetch first pair
int err = lfs_dir_fetch(lfs, &dir->m, pair);
if (err) {
return err;
}
// setup entry
dir->head[0] = dir->m.pair[0];
dir->head[1] = dir->m.pair[1];
dir->id = 0;
dir->pos = 0;
// add to list of mdirs
dir->type = LFS_TYPE_DIR;
lfs_mlist_append(lfs, (struct lfs_mlist *)dir);
return 0;
}
static int lfs_dir_close_(lfs_t *lfs, lfs_dir_t *dir) {
// remove from list of mdirs
lfs_mlist_remove(lfs, (struct lfs_mlist *)dir);
return 0;
}
static int lfs_dir_read_(lfs_t *lfs, lfs_dir_t *dir, struct lfs_info *info) {
memset(info, 0, sizeof(*info));
// special offset for '.' and '..'
if (dir->pos == 0) {
info->type = LFS_TYPE_DIR;
strcpy(info->name, ".");
dir->pos += 1;
return true;
} else if (dir->pos == 1) {
info->type = LFS_TYPE_DIR;
strcpy(info->name, "..");
dir->pos += 1;
return true;
}
while (true) {
if (dir->id == dir->m.count) {
if (!dir->m.split) {
return false;
}
int err = lfs_dir_fetch(lfs, &dir->m, dir->m.tail);
if (err) {
return err;
}
dir->id = 0;
}
int err = lfs_dir_getinfo(lfs, &dir->m, dir->id, info);
if (err && err != LFS_ERR_NOENT) {
return err;
}
dir->id += 1;
if (err != LFS_ERR_NOENT) {
break;
}
}
dir->pos += 1;
return true;
}
static int lfs_dir_seek_(lfs_t *lfs, lfs_dir_t *dir, lfs_off_t off) {
// simply walk from head dir
int err = lfs_dir_rewind_(lfs, dir);
if (err) {
return err;
}
// first two for ./..
dir->pos = lfs_min(2, off);
off -= dir->pos;
// skip superblock entry
dir->id = (off > 0 && lfs_pair_cmp(dir->head, lfs->root) == 0);
while (off > 0) {
if (dir->id == dir->m.count) {
if (!dir->m.split) {
return LFS_ERR_INVAL;
}
err = lfs_dir_fetch(lfs, &dir->m, dir->m.tail);
if (err) {
return err;
}
dir->id = 0;
}
int diff = lfs_min(dir->m.count - dir->id, off);
dir->id += diff;
dir->pos += diff;
off -= diff;
}
return 0;
}
static lfs_soff_t lfs_dir_tell_(lfs_t *lfs, lfs_dir_t *dir) {
(void)lfs;
return dir->pos;
}
static int lfs_dir_rewind_(lfs_t *lfs, lfs_dir_t *dir) {
// reload the head dir
int err = lfs_dir_fetch(lfs, &dir->m, dir->head);
if (err) {
return err;
}
dir->id = 0;
dir->pos = 0;
return 0;
}
/// File index list operations ///
static int lfs_ctz_index(lfs_t *lfs, lfs_off_t *off) {
lfs_off_t size = *off;
lfs_off_t b = lfs->cfg->block_size - 2*4;
lfs_off_t i = size / b;
if (i == 0) {
return 0;
}
i = (size - 4*(lfs_popc(i-1)+2)) / b;
*off = size - b*i - 4*lfs_popc(i);
return i;
}
static int lfs_ctz_find(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache,
lfs_block_t head, lfs_size_t size,
lfs_size_t pos, lfs_block_t *block, lfs_off_t *off) {
if (size == 0) {
*block = LFS_BLOCK_NULL;
*off = 0;
return 0;
}
lfs_off_t current = lfs_ctz_index(lfs, &(lfs_off_t){size-1});
lfs_off_t target = lfs_ctz_index(lfs, &pos);
while (current > target) {
lfs_size_t skip = lfs_min(
lfs_npw2(current-target+1) - 1,
lfs_ctz(current));
int err = lfs_bd_read(lfs,
pcache, rcache, sizeof(head),
head, 4*skip, &head, sizeof(head));
head = lfs_fromle32(head);
if (err) {
return err;
}
current -= 1 << skip;
}
*block = head;
*off = pos;
return 0;
}
#ifndef LFS_READONLY
static int lfs_ctz_extend(lfs_t *lfs,
lfs_cache_t *pcache, lfs_cache_t *rcache,
lfs_block_t head, lfs_size_t size,
lfs_block_t *block, lfs_off_t *off) {
while (true) {
// go ahead and grab a block
lfs_block_t nblock;
int err = lfs_alloc(lfs, &nblock);
if (err) {
return err;
}
{
err = lfs_bd_erase(lfs, nblock);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
if (size == 0) {
*block = nblock;
*off = 0;
return 0;
}
lfs_size_t noff = size - 1;
lfs_off_t index = lfs_ctz_index(lfs, &noff);
noff = noff + 1;
// just copy out the last block if it is incomplete
if (noff != lfs->cfg->block_size) {
for (lfs_off_t i = 0; i < noff; i++) {
uint8_t data;
err = lfs_bd_read(lfs,
NULL, rcache, noff-i,
head, i, &data, 1);
if (err) {
return err;
}
err = lfs_bd_prog(lfs,
pcache, rcache, true,
nblock, i, &data, 1);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
}
*block = nblock;
*off = noff;
return 0;
}
// append block
index += 1;
lfs_size_t skips = lfs_ctz(index) + 1;
lfs_block_t nhead = head;
for (lfs_off_t i = 0; i < skips; i++) {
nhead = lfs_tole32(nhead);
err = lfs_bd_prog(lfs, pcache, rcache, true,
nblock, 4*i, &nhead, 4);
nhead = lfs_fromle32(nhead);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
if (i != skips-1) {
err = lfs_bd_read(lfs,
NULL, rcache, sizeof(nhead),
nhead, 4*i, &nhead, sizeof(nhead));
nhead = lfs_fromle32(nhead);
if (err) {
return err;
}
}
}
*block = nblock;
*off = 4*skips;
return 0;
}
relocate:
LFS_DEBUG("Bad block at 0x%"PRIx32, nblock);
// just clear cache and try a new block
lfs_cache_drop(lfs, pcache);
}
}
#endif
static int lfs_ctz_traverse(lfs_t *lfs,
const lfs_cache_t *pcache, lfs_cache_t *rcache,
lfs_block_t head, lfs_size_t size,
int (*cb)(void*, lfs_block_t), void *data) {
if (size == 0) {
return 0;
}
lfs_off_t index = lfs_ctz_index(lfs, &(lfs_off_t){size-1});
while (true) {
int err = cb(data, head);
if (err) {
return err;
}
if (index == 0) {
return 0;
}
lfs_block_t heads[2];
int count = 2 - (index & 1);
err = lfs_bd_read(lfs,
pcache, rcache, count*sizeof(head),
head, 0, &heads, count*sizeof(head));
heads[0] = lfs_fromle32(heads[0]);
heads[1] = lfs_fromle32(heads[1]);
if (err) {
return err;
}
for (int i = 0; i < count-1; i++) {
err = cb(data, heads[i]);
if (err) {
return err;
}
}
head = heads[count-1];
index -= count;
}
}
/// Top level file operations ///
static int lfs_file_opencfg_(lfs_t *lfs, lfs_file_t *file,
const char *path, int flags,
const struct lfs_file_config *cfg) {
#ifndef LFS_READONLY
// deorphan if we haven't yet, needed at most once after poweron
if ((flags & LFS_O_WRONLY) == LFS_O_WRONLY) {
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
}
#else
LFS_ASSERT((flags & LFS_O_RDONLY) == LFS_O_RDONLY);
#endif
// setup simple file details
int err;
file->cfg = cfg;
file->flags = flags;
file->pos = 0;
file->off = 0;
file->cache.buffer = NULL;
// allocate entry for file if it doesn't exist
lfs_stag_t tag = lfs_dir_find(lfs, &file->m, &path, &file->id);
if (tag < 0 && !(tag == LFS_ERR_NOENT && lfs_path_islast(path))) {
err = tag;
goto cleanup;
}
// get id, add to list of mdirs to catch update changes
file->type = LFS_TYPE_REG;
lfs_mlist_append(lfs, (struct lfs_mlist *)file);
#ifdef LFS_READONLY
if (tag == LFS_ERR_NOENT) {
err = LFS_ERR_NOENT;
goto cleanup;
#else
if (tag == LFS_ERR_NOENT) {
if (!(flags & LFS_O_CREAT)) {
err = LFS_ERR_NOENT;
goto cleanup;
}
// don't allow trailing slashes
if (lfs_path_isdir(path)) {
err = LFS_ERR_NOTDIR;
goto cleanup;
}
// check that name fits
lfs_size_t nlen = lfs_path_namelen(path);
if (nlen > lfs->name_max) {
err = LFS_ERR_NAMETOOLONG;
goto cleanup;
}
// get next slot and create entry to remember name
err = lfs_dir_commit(lfs, &file->m, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_CREATE, file->id, 0), NULL},
{LFS_MKTAG(LFS_TYPE_REG, file->id, nlen), path},
{LFS_MKTAG(LFS_TYPE_INLINESTRUCT, file->id, 0), NULL}));
// it may happen that the file name doesn't fit in the metadata blocks, e.g., a 256 byte file name will
// not fit in a 128 byte block.
err = (err == LFS_ERR_NOSPC) ? LFS_ERR_NAMETOOLONG : err;
if (err) {
goto cleanup;
}
tag = LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, 0);
} else if (flags & LFS_O_EXCL) {
err = LFS_ERR_EXIST;
goto cleanup;
#endif
} else if (lfs_tag_type3(tag) != LFS_TYPE_REG) {
err = LFS_ERR_ISDIR;
goto cleanup;
#ifndef LFS_READONLY
} else if (flags & LFS_O_TRUNC) {
// truncate if requested
tag = LFS_MKTAG(LFS_TYPE_INLINESTRUCT, file->id, 0);
file->flags |= LFS_F_DIRTY;
#endif
} else {
// try to load what's on disk, if it's inlined we'll fix it later
tag = lfs_dir_get(lfs, &file->m, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, file->id, 8), &file->ctz);
if (tag < 0) {
err = tag;
goto cleanup;
}
lfs_ctz_fromle32(&file->ctz);
}
// fetch attrs
for (unsigned i = 0; i < file->cfg->attr_count; i++) {
// if opened for read / read-write operations
if ((file->flags & LFS_O_RDONLY) == LFS_O_RDONLY) {
lfs_stag_t res = lfs_dir_get(lfs, &file->m,
LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_USERATTR + file->cfg->attrs[i].type,
file->id, file->cfg->attrs[i].size),
file->cfg->attrs[i].buffer);
if (res < 0 && res != LFS_ERR_NOENT) {
err = res;
goto cleanup;
}
}
#ifndef LFS_READONLY
// if opened for write / read-write operations
if ((file->flags & LFS_O_WRONLY) == LFS_O_WRONLY) {
if (file->cfg->attrs[i].size > lfs->attr_max) {
err = LFS_ERR_NOSPC;
goto cleanup;
}
file->flags |= LFS_F_DIRTY;
}
#endif
}
// allocate buffer if needed
if (file->cfg->buffer) {
file->cache.buffer = file->cfg->buffer;
} else {
file->cache.buffer = lfs_malloc(lfs->cfg->cache_size);
if (!file->cache.buffer) {
err = LFS_ERR_NOMEM;
goto cleanup;
}
}
// zero to avoid information leak
lfs_cache_zero(lfs, &file->cache);
if (lfs_tag_type3(tag) == LFS_TYPE_INLINESTRUCT) {
// load inline files
file->ctz.head = LFS_BLOCK_INLINE;
file->ctz.size = lfs_tag_size(tag);
file->flags |= LFS_F_INLINE;
file->cache.block = file->ctz.head;
file->cache.off = 0;
file->cache.size = lfs->cfg->cache_size;
// don't always read (may be new/trunc file)
if (file->ctz.size > 0) {
lfs_stag_t res = lfs_dir_get(lfs, &file->m,
LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, file->id,
lfs_min(file->cache.size, 0x3fe)),
file->cache.buffer);
if (res < 0) {
err = res;
goto cleanup;
}
}
}
return 0;
cleanup:
// clean up lingering resources
#ifndef LFS_READONLY
file->flags |= LFS_F_ERRED;
#endif
lfs_file_close_(lfs, file);
return err;
}
#ifndef LFS_NO_MALLOC
static int lfs_file_open_(lfs_t *lfs, lfs_file_t *file,
const char *path, int flags) {
static const struct lfs_file_config defaults = {0};
int err = lfs_file_opencfg_(lfs, file, path, flags, &defaults);
return err;
}
#endif
static int lfs_file_close_(lfs_t *lfs, lfs_file_t *file) {
#ifndef LFS_READONLY
int err = lfs_file_sync_(lfs, file);
#else
int err = 0;
#endif
// remove from list of mdirs
lfs_mlist_remove(lfs, (struct lfs_mlist*)file);
// clean up memory
if (!file->cfg->buffer) {
lfs_free(file->cache.buffer);
}
return err;
}
#ifndef LFS_READONLY
static int lfs_file_relocate(lfs_t *lfs, lfs_file_t *file) {
while (true) {
// just relocate what exists into new block
lfs_block_t nblock;
int err = lfs_alloc(lfs, &nblock);
if (err) {
return err;
}
err = lfs_bd_erase(lfs, nblock);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
// either read from dirty cache or disk
for (lfs_off_t i = 0; i < file->off; i++) {
uint8_t data;
if (file->flags & LFS_F_INLINE) {
err = lfs_dir_getread(lfs, &file->m,
// note we evict inline files before they can be dirty
NULL, &file->cache, file->off-i,
LFS_MKTAG(0xfff, 0x1ff, 0),
LFS_MKTAG(LFS_TYPE_INLINESTRUCT, file->id, 0),
i, &data, 1);
if (err) {
return err;
}
} else {
err = lfs_bd_read(lfs,
&file->cache, &lfs->rcache, file->off-i,
file->block, i, &data, 1);
if (err) {
return err;
}
}
err = lfs_bd_prog(lfs,
&lfs->pcache, &lfs->rcache, true,
nblock, i, &data, 1);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
}
// copy over new state of file
memcpy(file->cache.buffer, lfs->pcache.buffer, lfs->cfg->cache_size);
file->cache.block = lfs->pcache.block;
file->cache.off = lfs->pcache.off;
file->cache.size = lfs->pcache.size;
lfs_cache_zero(lfs, &lfs->pcache);
file->block = nblock;
file->flags |= LFS_F_WRITING;
return 0;
relocate:
LFS_DEBUG("Bad block at 0x%"PRIx32, nblock);
// just clear cache and try a new block
lfs_cache_drop(lfs, &lfs->pcache);
}
}
#endif
#ifndef LFS_READONLY
static int lfs_file_outline(lfs_t *lfs, lfs_file_t *file) {
file->off = file->pos;
lfs_alloc_ckpoint(lfs);
int err = lfs_file_relocate(lfs, file);
if (err) {
return err;
}
file->flags &= ~LFS_F_INLINE;
return 0;
}
#endif
static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
if (file->flags & LFS_F_READING) {
if (!(file->flags & LFS_F_INLINE)) {
lfs_cache_drop(lfs, &file->cache);
}
file->flags &= ~LFS_F_READING;
}
#ifndef LFS_READONLY
if (file->flags & LFS_F_WRITING) {
lfs_off_t pos = file->pos;
if (!(file->flags & LFS_F_INLINE)) {
// copy over anything after current branch
lfs_file_t orig = {
.ctz.head = file->ctz.head,
.ctz.size = file->ctz.size,
.flags = LFS_O_RDONLY,
.pos = file->pos,
.cache = lfs->rcache,
};
lfs_cache_drop(lfs, &lfs->rcache);
while (file->pos < file->ctz.size) {
// copy over a byte at a time, leave it up to caching
// to make this efficient
uint8_t data;
lfs_ssize_t res = lfs_file_flushedread(lfs, &orig, &data, 1);
if (res < 0) {
return res;
}
res = lfs_file_flushedwrite(lfs, file, &data, 1);
if (res < 0) {
return res;
}
// keep our reference to the rcache in sync
if (lfs->rcache.block != LFS_BLOCK_NULL) {
lfs_cache_drop(lfs, &orig.cache);
lfs_cache_drop(lfs, &lfs->rcache);
}
}
// write out what we have
while (true) {
int err = lfs_bd_flush(lfs, &file->cache, &lfs->rcache, true);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
return err;
}
break;
relocate:
LFS_DEBUG("Bad block at 0x%"PRIx32, file->block);
err = lfs_file_relocate(lfs, file);
if (err) {
return err;
}
}
} else {
file->pos = lfs_max(file->pos, file->ctz.size);
}
// actual file updates
file->ctz.head = file->block;
file->ctz.size = file->pos;
file->flags &= ~LFS_F_WRITING;
file->flags |= LFS_F_DIRTY;
file->pos = pos;
}
#endif
return 0;
}
#ifndef LFS_READONLY
static int lfs_file_sync_(lfs_t *lfs, lfs_file_t *file) {
if (file->flags & LFS_F_ERRED) {
// it's not safe to do anything if our file errored
return 0;
}
int err = lfs_file_flush(lfs, file);
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
if ((file->flags & LFS_F_DIRTY) &&
!lfs_pair_isnull(file->m.pair)) {
// before we commit metadata, we need sync the disk to make sure
// data writes don't complete after metadata writes
if (!(file->flags & LFS_F_INLINE)) {
err = lfs_bd_sync(lfs, &lfs->pcache, &lfs->rcache, false);
if (err) {
return err;
}
}
// update dir entry
uint16_t type;
const void *buffer;
lfs_size_t size;
struct lfs_ctz ctz;
if (file->flags & LFS_F_INLINE) {
// inline the whole file
type = LFS_TYPE_INLINESTRUCT;
buffer = file->cache.buffer;
size = file->ctz.size;
} else {
// update the ctz reference
type = LFS_TYPE_CTZSTRUCT;
// copy ctz so alloc will work during a relocate
ctz = file->ctz;
lfs_ctz_tole32(&ctz);
buffer = &ctz;
size = sizeof(ctz);
}
// commit file data and attributes
err = lfs_dir_commit(lfs, &file->m, LFS_MKATTRS(
{LFS_MKTAG(type, file->id, size), buffer},
{LFS_MKTAG(LFS_FROM_USERATTRS, file->id,
file->cfg->attr_count), file->cfg->attrs}));
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
file->flags &= ~LFS_F_DIRTY;
}
return 0;
}
#endif
static lfs_ssize_t lfs_file_flushedread(lfs_t *lfs, lfs_file_t *file,
void *buffer, lfs_size_t size) {
uint8_t *data = buffer;
lfs_size_t nsize = size;
if (file->pos >= file->ctz.size) {
// eof if past end
return 0;
}
size = lfs_min(size, file->ctz.size - file->pos);
nsize = size;
while (nsize > 0) {
// check if we need a new block
if (!(file->flags & LFS_F_READING) ||
file->off == lfs->cfg->block_size) {
if (!(file->flags & LFS_F_INLINE)) {
int err = lfs_ctz_find(lfs, NULL, &file->cache,
file->ctz.head, file->ctz.size,
file->pos, &file->block, &file->off);
if (err) {
return err;
}
} else {
file->block = LFS_BLOCK_INLINE;
file->off = file->pos;
}
file->flags |= LFS_F_READING;
}
// read as much as we can in current block
lfs_size_t diff = lfs_min(nsize, lfs->cfg->block_size - file->off);
if (file->flags & LFS_F_INLINE) {
int err = lfs_dir_getread(lfs, &file->m,
NULL, &file->cache, lfs->cfg->block_size,
LFS_MKTAG(0xfff, 0x1ff, 0),
LFS_MKTAG(LFS_TYPE_INLINESTRUCT, file->id, 0),
file->off, data, diff);
if (err) {
return err;
}
} else {
int err = lfs_bd_read(lfs,
NULL, &file->cache, lfs->cfg->block_size,
file->block, file->off, data, diff);
if (err) {
return err;
}
}
file->pos += diff;
file->off += diff;
data += diff;
nsize -= diff;
}
return size;
}
static lfs_ssize_t lfs_file_read_(lfs_t *lfs, lfs_file_t *file,
void *buffer, lfs_size_t size) {
LFS_ASSERT((file->flags & LFS_O_RDONLY) == LFS_O_RDONLY);
#ifndef LFS_READONLY
if (file->flags & LFS_F_WRITING) {
// flush out any writes
int err = lfs_file_flush(lfs, file);
if (err) {
return err;
}
}
#endif
return lfs_file_flushedread(lfs, file, buffer, size);
}
#ifndef LFS_READONLY
static lfs_ssize_t lfs_file_flushedwrite(lfs_t *lfs, lfs_file_t *file,
const void *buffer, lfs_size_t size) {
const uint8_t *data = buffer;
lfs_size_t nsize = size;
if ((file->flags & LFS_F_INLINE) &&
lfs_max(file->pos+nsize, file->ctz.size) > lfs->inline_max) {
// inline file doesn't fit anymore
int err = lfs_file_outline(lfs, file);
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
}
while (nsize > 0) {
// check if we need a new block
if (!(file->flags & LFS_F_WRITING) ||
file->off == lfs->cfg->block_size) {
if (!(file->flags & LFS_F_INLINE)) {
if (!(file->flags & LFS_F_WRITING) && file->pos > 0) {
// find out which block we're extending from
int err = lfs_ctz_find(lfs, NULL, &file->cache,
file->ctz.head, file->ctz.size,
file->pos-1, &file->block, &(lfs_off_t){0});
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
// mark cache as dirty since we may have read data into it
lfs_cache_zero(lfs, &file->cache);
}
// extend file with new blocks
lfs_alloc_ckpoint(lfs);
int err = lfs_ctz_extend(lfs, &file->cache, &lfs->rcache,
file->block, file->pos,
&file->block, &file->off);
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
} else {
file->block = LFS_BLOCK_INLINE;
file->off = file->pos;
}
file->flags |= LFS_F_WRITING;
}
// program as much as we can in current block
lfs_size_t diff = lfs_min(nsize, lfs->cfg->block_size - file->off);
while (true) {
int err = lfs_bd_prog(lfs, &file->cache, &lfs->rcache, true,
file->block, file->off, data, diff);
if (err) {
if (err == LFS_ERR_CORRUPT) {
goto relocate;
}
file->flags |= LFS_F_ERRED;
return err;
}
break;
relocate:
err = lfs_file_relocate(lfs, file);
if (err) {
file->flags |= LFS_F_ERRED;
return err;
}
}
file->pos += diff;
file->off += diff;
data += diff;
nsize -= diff;
lfs_alloc_ckpoint(lfs);
}
return size;
}
static lfs_ssize_t lfs_file_write_(lfs_t *lfs, lfs_file_t *file,
const void *buffer, lfs_size_t size) {
LFS_ASSERT((file->flags & LFS_O_WRONLY) == LFS_O_WRONLY);
if (file->flags & LFS_F_READING) {
// drop any reads
int err = lfs_file_flush(lfs, file);
if (err) {
return err;
}
}
if ((file->flags & LFS_O_APPEND) && file->pos < file->ctz.size) {
file->pos = file->ctz.size;
}
if (file->pos + size > lfs->file_max) {
// Larger than file limit?
return LFS_ERR_FBIG;
}
if (!(file->flags & LFS_F_WRITING) && file->pos > file->ctz.size) {
// fill with zeros
lfs_off_t pos = file->pos;
file->pos = file->ctz.size;
while (file->pos < pos) {
lfs_ssize_t res = lfs_file_flushedwrite(lfs, file, &(uint8_t){0}, 1);
if (res < 0) {
return res;
}
}
}
lfs_ssize_t nsize = lfs_file_flushedwrite(lfs, file, buffer, size);
if (nsize < 0) {
return nsize;
}
file->flags &= ~LFS_F_ERRED;
return nsize;
}
#endif
static lfs_soff_t lfs_file_seek_(lfs_t *lfs, lfs_file_t *file,
lfs_soff_t off, int whence) {
// find new pos
//
// fortunately for us, littlefs is limited to 31-bit file sizes, so we
// don't have to worry too much about integer overflow
lfs_off_t npos = file->pos;
if (whence == LFS_SEEK_SET) {
npos = off;
} else if (whence == LFS_SEEK_CUR) {
npos = file->pos + (lfs_off_t)off;
} else if (whence == LFS_SEEK_END) {
npos = (lfs_off_t)lfs_file_size_(lfs, file) + (lfs_off_t)off;
}
if (npos > lfs->file_max) {
// file position out of range
return LFS_ERR_INVAL;
}
if (file->pos == npos) {
// noop - position has not changed
return npos;
}
// if we're only reading and our new offset is still in the file's cache
// we can avoid flushing and needing to reread the data
if ((file->flags & LFS_F_READING)
&& file->off != lfs->cfg->block_size) {
int oindex = lfs_ctz_index(lfs, &(lfs_off_t){file->pos});
lfs_off_t noff = npos;
int nindex = lfs_ctz_index(lfs, &noff);
if (oindex == nindex
&& noff >= file->cache.off
&& noff < file->cache.off + file->cache.size) {
file->pos = npos;
file->off = noff;
return npos;
}
}
// write out everything beforehand, may be noop if rdonly
int err = lfs_file_flush(lfs, file);
if (err) {
return err;
}
// update pos
file->pos = npos;
return npos;
}
#ifndef LFS_READONLY
static int lfs_file_truncate_(lfs_t *lfs, lfs_file_t *file, lfs_off_t size) {
LFS_ASSERT((file->flags & LFS_O_WRONLY) == LFS_O_WRONLY);
if (size > LFS_FILE_MAX) {
return LFS_ERR_INVAL;
}
lfs_off_t pos = file->pos;
lfs_off_t oldsize = lfs_file_size_(lfs, file);
if (size < oldsize) {
// revert to inline file?
if (size <= lfs->inline_max) {
// flush+seek to head
lfs_soff_t res = lfs_file_seek_(lfs, file, 0, LFS_SEEK_SET);
if (res < 0) {
return (int)res;
}
// read our data into rcache temporarily
lfs_cache_drop(lfs, &lfs->rcache);
res = lfs_file_flushedread(lfs, file,
lfs->rcache.buffer, size);
if (res < 0) {
return (int)res;
}
file->ctz.head = LFS_BLOCK_INLINE;
file->ctz.size = size;
file->flags |= LFS_F_DIRTY | LFS_F_READING | LFS_F_INLINE;
file->cache.block = file->ctz.head;
file->cache.off = 0;
file->cache.size = lfs->cfg->cache_size;
memcpy(file->cache.buffer, lfs->rcache.buffer, size);
} else {
// need to flush since directly changing metadata
int err = lfs_file_flush(lfs, file);
if (err) {
return err;
}
// lookup new head in ctz skip list
err = lfs_ctz_find(lfs, NULL, &file->cache,
file->ctz.head, file->ctz.size,
size-1, &file->block, &(lfs_off_t){0});
if (err) {
return err;
}
// need to set pos/block/off consistently so seeking back to
// the old position does not get confused
file->pos = size;
file->ctz.head = file->block;
file->ctz.size = size;
file->flags |= LFS_F_DIRTY | LFS_F_READING;
}
} else if (size > oldsize) {
// flush+seek if not already at end
lfs_soff_t res = lfs_file_seek_(lfs, file, 0, LFS_SEEK_END);
if (res < 0) {
return (int)res;
}
// fill with zeros
while (file->pos < size) {
res = lfs_file_write_(lfs, file, &(uint8_t){0}, 1);
if (res < 0) {
return (int)res;
}
}
}
// restore pos
lfs_soff_t res = lfs_file_seek_(lfs, file, pos, LFS_SEEK_SET);
if (res < 0) {
return (int)res;
}
return 0;
}
#endif
static lfs_soff_t lfs_file_tell_(lfs_t *lfs, lfs_file_t *file) {
(void)lfs;
return file->pos;
}
static int lfs_file_rewind_(lfs_t *lfs, lfs_file_t *file) {
lfs_soff_t res = lfs_file_seek_(lfs, file, 0, LFS_SEEK_SET);
if (res < 0) {
return (int)res;
}
return 0;
}
static lfs_soff_t lfs_file_size_(lfs_t *lfs, lfs_file_t *file) {
(void)lfs;
#ifndef LFS_READONLY
if (file->flags & LFS_F_WRITING) {
return lfs_max(file->pos, file->ctz.size);
}
#endif
return file->ctz.size;
}
/// General fs operations ///
static int lfs_stat_(lfs_t *lfs, const char *path, struct lfs_info *info) {
lfs_mdir_t cwd;
lfs_stag_t tag = lfs_dir_find(lfs, &cwd, &path, NULL);
if (tag < 0) {
return (int)tag;
}
// only allow trailing slashes on dirs
if (strchr(path, '/') != NULL
&& lfs_tag_type3(tag) != LFS_TYPE_DIR) {
return LFS_ERR_NOTDIR;
}
return lfs_dir_getinfo(lfs, &cwd, lfs_tag_id(tag), info);
}
#ifndef LFS_READONLY
static int lfs_remove_(lfs_t *lfs, const char *path) {
// deorphan if we haven't yet, needed at most once after poweron
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
lfs_mdir_t cwd;
lfs_stag_t tag = lfs_dir_find(lfs, &cwd, &path, NULL);
if (tag < 0 || lfs_tag_id(tag) == 0x3ff) {
return (tag < 0) ? (int)tag : LFS_ERR_INVAL;
}
struct lfs_mlist dir;
dir.next = lfs->mlist;
if (lfs_tag_type3(tag) == LFS_TYPE_DIR) {
// must be empty before removal
lfs_block_t pair[2];
lfs_stag_t res = lfs_dir_get(lfs, &cwd, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, lfs_tag_id(tag), 8), pair);
if (res < 0) {
return (int)res;
}
lfs_pair_fromle32(pair);
err = lfs_dir_fetch(lfs, &dir.m, pair);
if (err) {
return err;
}
if (dir.m.count > 0 || dir.m.split) {
return LFS_ERR_NOTEMPTY;
}
// mark fs as orphaned
err = lfs_fs_preporphans(lfs, +1);
if (err) {
return err;
}
// I know it's crazy but yes, dir can be changed by our parent's
// commit (if predecessor is child)
dir.type = 0;
dir.id = 0;
lfs->mlist = &dir;
}
// delete the entry
err = lfs_dir_commit(lfs, &cwd, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_DELETE, lfs_tag_id(tag), 0), NULL}));
if (err) {
lfs->mlist = dir.next;
return err;
}
lfs->mlist = dir.next;
if (lfs_gstate_hasorphans(&lfs->gstate)) {
LFS_ASSERT(lfs_tag_type3(tag) == LFS_TYPE_DIR);
// fix orphan
err = lfs_fs_preporphans(lfs, -1);
if (err) {
return err;
}
err = lfs_fs_pred(lfs, dir.m.pair, &cwd);
if (err) {
return err;
}
err = lfs_dir_drop(lfs, &cwd, &dir.m);
if (err) {
return err;
}
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_rename_(lfs_t *lfs, const char *oldpath, const char *newpath) {
// deorphan if we haven't yet, needed at most once after poweron
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
// find old entry
lfs_mdir_t oldcwd;
lfs_stag_t oldtag = lfs_dir_find(lfs, &oldcwd, &oldpath, NULL);
if (oldtag < 0 || lfs_tag_id(oldtag) == 0x3ff) {
return (oldtag < 0) ? (int)oldtag : LFS_ERR_INVAL;
}
// find new entry
lfs_mdir_t newcwd;
uint16_t newid;
lfs_stag_t prevtag = lfs_dir_find(lfs, &newcwd, &newpath, &newid);
if ((prevtag < 0 || lfs_tag_id(prevtag) == 0x3ff) &&
!(prevtag == LFS_ERR_NOENT && lfs_path_islast(newpath))) {
return (prevtag < 0) ? (int)prevtag : LFS_ERR_INVAL;
}
// if we're in the same pair there's a few special cases...
bool samepair = (lfs_pair_cmp(oldcwd.pair, newcwd.pair) == 0);
uint16_t newoldid = lfs_tag_id(oldtag);
struct lfs_mlist prevdir;
prevdir.next = lfs->mlist;
if (prevtag == LFS_ERR_NOENT) {
// if we're a file, don't allow trailing slashes
if (lfs_path_isdir(newpath)
&& lfs_tag_type3(oldtag) != LFS_TYPE_DIR) {
return LFS_ERR_NOTDIR;
}
// check that name fits
lfs_size_t nlen = lfs_path_namelen(newpath);
if (nlen > lfs->name_max) {
return LFS_ERR_NAMETOOLONG;
}
// there is a small chance we are being renamed in the same
// directory/ to an id less than our old id, the global update
// to handle this is a bit messy
if (samepair && newid <= newoldid) {
newoldid += 1;
}
} else if (lfs_tag_type3(prevtag) != lfs_tag_type3(oldtag)) {
return (lfs_tag_type3(prevtag) == LFS_TYPE_DIR)
? LFS_ERR_ISDIR
: LFS_ERR_NOTDIR;
} else if (samepair && newid == newoldid) {
// we're renaming to ourselves??
return 0;
} else if (lfs_tag_type3(prevtag) == LFS_TYPE_DIR) {
// must be empty before removal
lfs_block_t prevpair[2];
lfs_stag_t res = lfs_dir_get(lfs, &newcwd, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, newid, 8), prevpair);
if (res < 0) {
return (int)res;
}
lfs_pair_fromle32(prevpair);
// must be empty before removal
err = lfs_dir_fetch(lfs, &prevdir.m, prevpair);
if (err) {
return err;
}
if (prevdir.m.count > 0 || prevdir.m.split) {
return LFS_ERR_NOTEMPTY;
}
// mark fs as orphaned
err = lfs_fs_preporphans(lfs, +1);
if (err) {
return err;
}
// I know it's crazy but yes, dir can be changed by our parent's
// commit (if predecessor is child)
prevdir.type = 0;
prevdir.id = 0;
lfs->mlist = &prevdir;
}
if (!samepair) {
lfs_fs_prepmove(lfs, newoldid, oldcwd.pair);
}
// move over all attributes
err = lfs_dir_commit(lfs, &newcwd, LFS_MKATTRS(
{LFS_MKTAG_IF(prevtag != LFS_ERR_NOENT,
LFS_TYPE_DELETE, newid, 0), NULL},
{LFS_MKTAG(LFS_TYPE_CREATE, newid, 0), NULL},
{LFS_MKTAG(lfs_tag_type3(oldtag),
newid, lfs_path_namelen(newpath)), newpath},
{LFS_MKTAG(LFS_FROM_MOVE, newid, lfs_tag_id(oldtag)), &oldcwd},
{LFS_MKTAG_IF(samepair,
LFS_TYPE_DELETE, newoldid, 0), NULL}));
if (err) {
lfs->mlist = prevdir.next;
return err;
}
// let commit clean up after move (if we're different! otherwise move
// logic already fixed it for us)
if (!samepair && lfs_gstate_hasmove(&lfs->gstate)) {
// prep gstate and delete move id
lfs_fs_prepmove(lfs, 0x3ff, NULL);
err = lfs_dir_commit(lfs, &oldcwd, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_DELETE, lfs_tag_id(oldtag), 0), NULL}));
if (err) {
lfs->mlist = prevdir.next;
return err;
}
}
lfs->mlist = prevdir.next;
if (lfs_gstate_hasorphans(&lfs->gstate)) {
LFS_ASSERT(prevtag != LFS_ERR_NOENT
&& lfs_tag_type3(prevtag) == LFS_TYPE_DIR);
// fix orphan
err = lfs_fs_preporphans(lfs, -1);
if (err) {
return err;
}
err = lfs_fs_pred(lfs, prevdir.m.pair, &newcwd);
if (err) {
return err;
}
err = lfs_dir_drop(lfs, &newcwd, &prevdir.m);
if (err) {
return err;
}
}
return 0;
}
#endif
static lfs_ssize_t lfs_getattr_(lfs_t *lfs, const char *path,
uint8_t type, void *buffer, lfs_size_t size) {
lfs_mdir_t cwd;
lfs_stag_t tag = lfs_dir_find(lfs, &cwd, &path, NULL);
if (tag < 0) {
return tag;
}
uint16_t id = lfs_tag_id(tag);
if (id == 0x3ff) {
// special case for root
id = 0;
int err = lfs_dir_fetch(lfs, &cwd, lfs->root);
if (err) {
return err;
}
}
tag = lfs_dir_get(lfs, &cwd, LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_USERATTR + type,
id, lfs_min(size, lfs->attr_max)),
buffer);
if (tag < 0) {
if (tag == LFS_ERR_NOENT) {
return LFS_ERR_NOATTR;
}
return tag;
}
return lfs_tag_size(tag);
}
#ifndef LFS_READONLY
static int lfs_commitattr(lfs_t *lfs, const char *path,
uint8_t type, const void *buffer, lfs_size_t size) {
lfs_mdir_t cwd;
lfs_stag_t tag = lfs_dir_find(lfs, &cwd, &path, NULL);
if (tag < 0) {
return tag;
}
uint16_t id = lfs_tag_id(tag);
if (id == 0x3ff) {
// special case for root
id = 0;
int err = lfs_dir_fetch(lfs, &cwd, lfs->root);
if (err) {
return err;
}
}
return lfs_dir_commit(lfs, &cwd, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_USERATTR + type, id, size), buffer}));
}
#endif
#ifndef LFS_READONLY
static int lfs_setattr_(lfs_t *lfs, const char *path,
uint8_t type, const void *buffer, lfs_size_t size) {
if (size > lfs->attr_max) {
return LFS_ERR_NOSPC;
}
return lfs_commitattr(lfs, path, type, buffer, size);
}
#endif
#ifndef LFS_READONLY
static int lfs_removeattr_(lfs_t *lfs, const char *path, uint8_t type) {
return lfs_commitattr(lfs, path, type, NULL, 0x3ff);
}
#endif
/// Filesystem operations ///
// compile time checks, see lfs.h for why these limits exist
#if LFS_NAME_MAX > 1022
#error "Invalid LFS_NAME_MAX, must be <= 1022"
#endif
#if LFS_FILE_MAX > 2147483647
#error "Invalid LFS_FILE_MAX, must be <= 2147483647"
#endif
#if LFS_ATTR_MAX > 1022
#error "Invalid LFS_ATTR_MAX, must be <= 1022"
#endif
// common filesystem initialization
static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
lfs->cfg = cfg;
lfs->block_count = cfg->block_count; // May be 0
int err = 0;
#ifdef LFS_MULTIVERSION
// this driver only supports minor version < current minor version
LFS_ASSERT(!lfs->cfg->disk_version || (
(0xffff & (lfs->cfg->disk_version >> 16))
== LFS_DISK_VERSION_MAJOR
&& (0xffff & (lfs->cfg->disk_version >> 0))
<= LFS_DISK_VERSION_MINOR));
#endif
// check that bool is a truthy-preserving type
//
// note the most common reason for this failure is a before-c99 compiler,
// which littlefs currently does not support
LFS_ASSERT((bool)0x80000000);
// check that the required io functions are provided
LFS_ASSERT(lfs->cfg->read != NULL);
#ifndef LFS_READONLY
LFS_ASSERT(lfs->cfg->prog != NULL);
LFS_ASSERT(lfs->cfg->erase != NULL);
LFS_ASSERT(lfs->cfg->sync != NULL);
#endif
// validate that the lfs-cfg sizes were initiated properly before
// performing any arithmetic logics with them
LFS_ASSERT(lfs->cfg->read_size != 0);
LFS_ASSERT(lfs->cfg->prog_size != 0);
LFS_ASSERT(lfs->cfg->cache_size != 0);
// check that block size is a multiple of cache size is a multiple
// of prog and read sizes
LFS_ASSERT(lfs->cfg->cache_size % lfs->cfg->read_size == 0);
LFS_ASSERT(lfs->cfg->cache_size % lfs->cfg->prog_size == 0);
LFS_ASSERT(lfs->cfg->block_size % lfs->cfg->cache_size == 0);
// check that the block size is large enough to fit all ctz pointers
LFS_ASSERT(lfs->cfg->block_size >= 128);
// this is the exact calculation for all ctz pointers, if this fails
// and the simpler assert above does not, math must be broken
LFS_ASSERT(4*lfs_npw2(0xffffffff / (lfs->cfg->block_size-2*4))
<= lfs->cfg->block_size);
// block_cycles = 0 is no longer supported.
//
// block_cycles is the number of erase cycles before littlefs evicts
// metadata logs as a part of wear leveling. Suggested values are in the
// range of 100-1000, or set block_cycles to -1 to disable block-level
// wear-leveling.
LFS_ASSERT(lfs->cfg->block_cycles != 0);
// check that compact_thresh makes sense
//
// metadata can't be compacted below block_size/2, and metadata can't
// exceed a block_size
LFS_ASSERT(lfs->cfg->compact_thresh == 0
|| lfs->cfg->compact_thresh >= lfs->cfg->block_size/2);
LFS_ASSERT(lfs->cfg->compact_thresh == (lfs_size_t)-1
|| lfs->cfg->compact_thresh <= lfs->cfg->block_size);
// check that metadata_max is a multiple of read_size and prog_size,
// and a factor of the block_size
LFS_ASSERT(!lfs->cfg->metadata_max
|| lfs->cfg->metadata_max % lfs->cfg->read_size == 0);
LFS_ASSERT(!lfs->cfg->metadata_max
|| lfs->cfg->metadata_max % lfs->cfg->prog_size == 0);
LFS_ASSERT(!lfs->cfg->metadata_max
|| lfs->cfg->block_size % lfs->cfg->metadata_max == 0);
// setup read cache
if (lfs->cfg->read_buffer) {
lfs->rcache.buffer = lfs->cfg->read_buffer;
} else {
lfs->rcache.buffer = lfs_malloc(lfs->cfg->cache_size);
if (!lfs->rcache.buffer) {
err = LFS_ERR_NOMEM;
goto cleanup;
}
}
// setup program cache
if (lfs->cfg->prog_buffer) {
lfs->pcache.buffer = lfs->cfg->prog_buffer;
} else {
lfs->pcache.buffer = lfs_malloc(lfs->cfg->cache_size);
if (!lfs->pcache.buffer) {
err = LFS_ERR_NOMEM;
goto cleanup;
}
}
// zero to avoid information leaks
lfs_cache_zero(lfs, &lfs->rcache);
lfs_cache_zero(lfs, &lfs->pcache);
// setup lookahead buffer, note mount finishes initializing this after
// we establish a decent pseudo-random seed
LFS_ASSERT(lfs->cfg->lookahead_size > 0);
if (lfs->cfg->lookahead_buffer) {
lfs->lookahead.buffer = lfs->cfg->lookahead_buffer;
} else {
lfs->lookahead.buffer = lfs_malloc(lfs->cfg->lookahead_size);
if (!lfs->lookahead.buffer) {
err = LFS_ERR_NOMEM;
goto cleanup;
}
}
// check that the size limits are sane
LFS_ASSERT(lfs->cfg->name_max <= LFS_NAME_MAX);
lfs->name_max = lfs->cfg->name_max;
if (!lfs->name_max) {
lfs->name_max = LFS_NAME_MAX;
}
LFS_ASSERT(lfs->cfg->file_max <= LFS_FILE_MAX);
lfs->file_max = lfs->cfg->file_max;
if (!lfs->file_max) {
lfs->file_max = LFS_FILE_MAX;
}
LFS_ASSERT(lfs->cfg->attr_max <= LFS_ATTR_MAX);
lfs->attr_max = lfs->cfg->attr_max;
if (!lfs->attr_max) {
lfs->attr_max = LFS_ATTR_MAX;
}
LFS_ASSERT(lfs->cfg->metadata_max <= lfs->cfg->block_size);
LFS_ASSERT(lfs->cfg->inline_max == (lfs_size_t)-1
|| lfs->cfg->inline_max <= lfs->cfg->cache_size);
LFS_ASSERT(lfs->cfg->inline_max == (lfs_size_t)-1
|| lfs->cfg->inline_max <= lfs->attr_max);
LFS_ASSERT(lfs->cfg->inline_max == (lfs_size_t)-1
|| lfs->cfg->inline_max <= ((lfs->cfg->metadata_max)
? lfs->cfg->metadata_max
: lfs->cfg->block_size)/8);
lfs->inline_max = lfs->cfg->inline_max;
if (lfs->inline_max == (lfs_size_t)-1) {
lfs->inline_max = 0;
} else if (lfs->inline_max == 0) {
lfs->inline_max = lfs_min(
lfs->cfg->cache_size,
lfs_min(
lfs->attr_max,
((lfs->cfg->metadata_max)
? lfs->cfg->metadata_max
: lfs->cfg->block_size)/8));
}
// setup default state
lfs->root[0] = LFS_BLOCK_NULL;
lfs->root[1] = LFS_BLOCK_NULL;
lfs->mlist = NULL;
lfs->seed = 0;
lfs->gdisk = (lfs_gstate_t){0};
lfs->gstate = (lfs_gstate_t){0};
lfs->gdelta = (lfs_gstate_t){0};
#ifdef LFS_MIGRATE
lfs->lfs1 = NULL;
#endif
return 0;
cleanup:
lfs_deinit(lfs);
return err;
}
static int lfs_deinit(lfs_t *lfs) {
// free allocated memory
if (!lfs->cfg->read_buffer) {
lfs_free(lfs->rcache.buffer);
}
if (!lfs->cfg->prog_buffer) {
lfs_free(lfs->pcache.buffer);
}
if (!lfs->cfg->lookahead_buffer) {
lfs_free(lfs->lookahead.buffer);
}
return 0;
}
#ifndef LFS_READONLY
static int lfs_format_(lfs_t *lfs, const struct lfs_config *cfg) {
int err = 0;
{
err = lfs_init(lfs, cfg);
if (err) {
return err;
}
LFS_ASSERT(cfg->block_count != 0);
// create free lookahead
memset(lfs->lookahead.buffer, 0, lfs->cfg->lookahead_size);
lfs->lookahead.start = 0;
lfs->lookahead.size = lfs_min(8*lfs->cfg->lookahead_size,
lfs->block_count);
lfs->lookahead.next = 0;
lfs_alloc_ckpoint(lfs);
// create root dir
lfs_mdir_t root;
err = lfs_dir_alloc(lfs, &root);
if (err) {
goto cleanup;
}
// write one superblock
lfs_superblock_t superblock = {
.version = lfs_fs_disk_version(lfs),
.block_size = lfs->cfg->block_size,
.block_count = lfs->block_count,
.name_max = lfs->name_max,
.file_max = lfs->file_max,
.attr_max = lfs->attr_max,
};
lfs_superblock_tole32(&superblock);
err = lfs_dir_commit(lfs, &root, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_CREATE, 0, 0), NULL},
{LFS_MKTAG(LFS_TYPE_SUPERBLOCK, 0, 8), "littlefs"},
{LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock}));
if (err) {
goto cleanup;
}
// force compaction to prevent accidentally mounting any
// older version of littlefs that may live on disk
root.erased = false;
err = lfs_dir_commit(lfs, &root, NULL, 0);
if (err) {
goto cleanup;
}
// sanity check that fetch works
err = lfs_dir_fetch(lfs, &root, (const lfs_block_t[2]){0, 1});
if (err) {
goto cleanup;
}
}
cleanup:
lfs_deinit(lfs);
return err;
}
#endif
struct lfs_tortoise_t {
lfs_block_t pair[2];
lfs_size_t i;
lfs_size_t period;
};
static int lfs_tortoise_detectcycles(
const lfs_mdir_t *dir, struct lfs_tortoise_t *tortoise) {
// detect cycles with Brent's algorithm
if (lfs_pair_issync(dir->tail, tortoise->pair)) {
LFS_WARN("Cycle detected in tail list");
return LFS_ERR_CORRUPT;
}
if (tortoise->i == tortoise->period) {
tortoise->pair[0] = dir->tail[0];
tortoise->pair[1] = dir->tail[1];
tortoise->i = 0;
tortoise->period *= 2;
}
tortoise->i += 1;
return LFS_ERR_OK;
}
static int lfs_mount_(lfs_t *lfs, const struct lfs_config *cfg) {
int err = lfs_init(lfs, cfg);
if (err) {
return err;
}
// scan directory blocks for superblock and any global updates
lfs_mdir_t dir = {.tail = {0, 1}};
struct lfs_tortoise_t tortoise = {
.pair = {LFS_BLOCK_NULL, LFS_BLOCK_NULL},
.i = 1,
.period = 1,
};
while (!lfs_pair_isnull(dir.tail)) {
err = lfs_tortoise_detectcycles(&dir, &tortoise);
if (err < 0) {
goto cleanup;
}
// fetch next block in tail list
lfs_stag_t tag = lfs_dir_fetchmatch(lfs, &dir, dir.tail,
LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_SUPERBLOCK, 0, 8),
NULL,
lfs_dir_find_match, &(struct lfs_dir_find_match){
lfs, "littlefs", 8});
if (tag < 0) {
err = tag;
goto cleanup;
}
// has superblock?
if (tag && !lfs_tag_isdelete(tag)) {
// update root
lfs->root[0] = dir.pair[0];
lfs->root[1] = dir.pair[1];
// grab superblock
lfs_superblock_t superblock;
tag = lfs_dir_get(lfs, &dir, LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock);
if (tag < 0) {
err = tag;
goto cleanup;
}
lfs_superblock_fromle32(&superblock);
// check version
uint16_t major_version = (0xffff & (superblock.version >> 16));
uint16_t minor_version = (0xffff & (superblock.version >> 0));
if (major_version != lfs_fs_disk_version_major(lfs)
|| minor_version > lfs_fs_disk_version_minor(lfs)) {
LFS_ERROR("Invalid version "
"v%"PRIu16".%"PRIu16" != v%"PRIu16".%"PRIu16,
major_version,
minor_version,
lfs_fs_disk_version_major(lfs),
lfs_fs_disk_version_minor(lfs));
err = LFS_ERR_INVAL;
goto cleanup;
}
// found older minor version? set an in-device only bit in the
// gstate so we know we need to rewrite the superblock before
// the first write
bool needssuperblock = false;
if (minor_version < lfs_fs_disk_version_minor(lfs)) {
LFS_DEBUG("Found older minor version "
"v%"PRIu16".%"PRIu16" < v%"PRIu16".%"PRIu16,
major_version,
minor_version,
lfs_fs_disk_version_major(lfs),
lfs_fs_disk_version_minor(lfs));
needssuperblock = true;
}
// note this bit is reserved on disk, so fetching more gstate
// will not interfere here
lfs_fs_prepsuperblock(lfs, needssuperblock);
// check superblock configuration
if (superblock.name_max) {
if (superblock.name_max > lfs->name_max) {
LFS_ERROR("Unsupported name_max (%"PRIu32" > %"PRIu32")",
superblock.name_max, lfs->name_max);
err = LFS_ERR_INVAL;
goto cleanup;
}
lfs->name_max = superblock.name_max;
}
if (superblock.file_max) {
if (superblock.file_max > lfs->file_max) {
LFS_ERROR("Unsupported file_max (%"PRIu32" > %"PRIu32")",
superblock.file_max, lfs->file_max);
err = LFS_ERR_INVAL;
goto cleanup;
}
lfs->file_max = superblock.file_max;
}
if (superblock.attr_max) {
if (superblock.attr_max > lfs->attr_max) {
LFS_ERROR("Unsupported attr_max (%"PRIu32" > %"PRIu32")",
superblock.attr_max, lfs->attr_max);
err = LFS_ERR_INVAL;
goto cleanup;
}
lfs->attr_max = superblock.attr_max;
// we also need to update inline_max in case attr_max changed
lfs->inline_max = lfs_min(lfs->inline_max, lfs->attr_max);
}
// this is where we get the block_count from disk if block_count=0
if (lfs->cfg->block_count
&& superblock.block_count != lfs->cfg->block_count) {
LFS_ERROR("Invalid block count (%"PRIu32" != %"PRIu32")",
superblock.block_count, lfs->cfg->block_count);
err = LFS_ERR_INVAL;
goto cleanup;
}
lfs->block_count = superblock.block_count;
if (superblock.block_size != lfs->cfg->block_size) {
LFS_ERROR("Invalid block size (%"PRIu32" != %"PRIu32")",
superblock.block_size, lfs->cfg->block_size);
err = LFS_ERR_INVAL;
goto cleanup;
}
}
// has gstate?
err = lfs_dir_getgstate(lfs, &dir, &lfs->gstate);
if (err) {
goto cleanup;
}
}
// update littlefs with gstate
if (!lfs_gstate_iszero(&lfs->gstate)) {
LFS_DEBUG("Found pending gstate 0x%08"PRIx32"%08"PRIx32"%08"PRIx32,
lfs->gstate.tag,
lfs->gstate.pair[0],
lfs->gstate.pair[1]);
}
lfs->gstate.tag += !lfs_tag_isvalid(lfs->gstate.tag);
lfs->gdisk = lfs->gstate;
// setup free lookahead, to distribute allocations uniformly across
// boots, we start the allocator at a random location
lfs->lookahead.start = lfs->seed % lfs->block_count;
lfs_alloc_drop(lfs);
return 0;
cleanup:
lfs_unmount_(lfs);
return err;
}
static int lfs_unmount_(lfs_t *lfs) {
return lfs_deinit(lfs);
}
/// Filesystem filesystem operations ///
static int lfs_fs_stat_(lfs_t *lfs, struct lfs_fsinfo *fsinfo) {
// if the superblock is up-to-date, we must be on the most recent
// minor version of littlefs
if (!lfs_gstate_needssuperblock(&lfs->gstate)) {
fsinfo->disk_version = lfs_fs_disk_version(lfs);
// otherwise we need to read the minor version on disk
} else {
// fetch the superblock
lfs_mdir_t dir;
int err = lfs_dir_fetch(lfs, &dir, lfs->root);
if (err) {
return err;
}
lfs_superblock_t superblock;
lfs_stag_t tag = lfs_dir_get(lfs, &dir, LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock);
if (tag < 0) {
return tag;
}
lfs_superblock_fromle32(&superblock);
// read the on-disk version
fsinfo->disk_version = superblock.version;
}
// filesystem geometry
fsinfo->block_size = lfs->cfg->block_size;
fsinfo->block_count = lfs->block_count;
// other on-disk configuration, we cache all of these for internal use
fsinfo->name_max = lfs->name_max;
fsinfo->file_max = lfs->file_max;
fsinfo->attr_max = lfs->attr_max;
return 0;
}
int lfs_fs_traverse_(lfs_t *lfs,
int (*cb)(void *data, lfs_block_t block), void *data,
bool includeorphans) {
// iterate over metadata pairs
lfs_mdir_t dir = {.tail = {0, 1}};
#ifdef LFS_MIGRATE
// also consider v1 blocks during migration
if (lfs->lfs1) {
int err = lfs1_traverse(lfs, cb, data);
if (err) {
return err;
}
dir.tail[0] = lfs->root[0];
dir.tail[1] = lfs->root[1];
}
#endif
struct lfs_tortoise_t tortoise = {
.pair = {LFS_BLOCK_NULL, LFS_BLOCK_NULL},
.i = 1,
.period = 1,
};
int err = LFS_ERR_OK;
while (!lfs_pair_isnull(dir.tail)) {
err = lfs_tortoise_detectcycles(&dir, &tortoise);
if (err < 0) {
return LFS_ERR_CORRUPT;
}
for (int i = 0; i < 2; i++) {
int err = cb(data, dir.tail[i]);
if (err) {
return err;
}
}
// iterate through ids in directory
int err = lfs_dir_fetch(lfs, &dir, dir.tail);
if (err) {
return err;
}
for (uint16_t id = 0; id < dir.count; id++) {
struct lfs_ctz ctz;
lfs_stag_t tag = lfs_dir_get(lfs, &dir, LFS_MKTAG(0x700, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_STRUCT, id, sizeof(ctz)), &ctz);
if (tag < 0) {
if (tag == LFS_ERR_NOENT) {
continue;
}
return tag;
}
lfs_ctz_fromle32(&ctz);
if (lfs_tag_type3(tag) == LFS_TYPE_CTZSTRUCT) {
err = lfs_ctz_traverse(lfs, NULL, &lfs->rcache,
ctz.head, ctz.size, cb, data);
if (err) {
return err;
}
} else if (includeorphans &&
lfs_tag_type3(tag) == LFS_TYPE_DIRSTRUCT) {
for (int i = 0; i < 2; i++) {
err = cb(data, (&ctz.head)[i]);
if (err) {
return err;
}
}
}
}
}
#ifndef LFS_READONLY
// iterate over any open files
for (lfs_file_t *f = (lfs_file_t*)lfs->mlist; f; f = f->next) {
if (f->type != LFS_TYPE_REG) {
continue;
}
if ((f->flags & LFS_F_DIRTY) && !(f->flags & LFS_F_INLINE)) {
int err = lfs_ctz_traverse(lfs, &f->cache, &lfs->rcache,
f->ctz.head, f->ctz.size, cb, data);
if (err) {
return err;
}
}
if ((f->flags & LFS_F_WRITING) && !(f->flags & LFS_F_INLINE)) {
int err = lfs_ctz_traverse(lfs, &f->cache, &lfs->rcache,
f->block, f->pos, cb, data);
if (err) {
return err;
}
}
}
#endif
return 0;
}
#ifndef LFS_READONLY
static int lfs_fs_pred(lfs_t *lfs,
const lfs_block_t pair[2], lfs_mdir_t *pdir) {
// iterate over all directory directory entries
pdir->tail[0] = 0;
pdir->tail[1] = 1;
struct lfs_tortoise_t tortoise = {
.pair = {LFS_BLOCK_NULL, LFS_BLOCK_NULL},
.i = 1,
.period = 1,
};
int err = LFS_ERR_OK;
while (!lfs_pair_isnull(pdir->tail)) {
err = lfs_tortoise_detectcycles(pdir, &tortoise);
if (err < 0) {
return LFS_ERR_CORRUPT;
}
if (lfs_pair_cmp(pdir->tail, pair) == 0) {
return 0;
}
int err = lfs_dir_fetch(lfs, pdir, pdir->tail);
if (err) {
return err;
}
}
return LFS_ERR_NOENT;
}
#endif
#ifndef LFS_READONLY
struct lfs_fs_parent_match {
lfs_t *lfs;
const lfs_block_t pair[2];
};
#endif
#ifndef LFS_READONLY
static int lfs_fs_parent_match(void *data,
lfs_tag_t tag, const void *buffer) {
struct lfs_fs_parent_match *find = data;
lfs_t *lfs = find->lfs;
const struct lfs_diskoff *disk = buffer;
(void)tag;
lfs_block_t child[2];
int err = lfs_bd_read(lfs,
&lfs->pcache, &lfs->rcache, lfs->cfg->block_size,
disk->block, disk->off, &child, sizeof(child));
if (err) {
return err;
}
lfs_pair_fromle32(child);
return (lfs_pair_cmp(child, find->pair) == 0) ? LFS_CMP_EQ : LFS_CMP_LT;
}
#endif
#ifndef LFS_READONLY
static lfs_stag_t lfs_fs_parent(lfs_t *lfs, const lfs_block_t pair[2],
lfs_mdir_t *parent) {
// use fetchmatch with callback to find pairs
parent->tail[0] = 0;
parent->tail[1] = 1;
struct lfs_tortoise_t tortoise = {
.pair = {LFS_BLOCK_NULL, LFS_BLOCK_NULL},
.i = 1,
.period = 1,
};
int err = LFS_ERR_OK;
while (!lfs_pair_isnull(parent->tail)) {
err = lfs_tortoise_detectcycles(parent, &tortoise);
if (err < 0) {
return err;
}
lfs_stag_t tag = lfs_dir_fetchmatch(lfs, parent, parent->tail,
LFS_MKTAG(0x7ff, 0, 0x3ff),
LFS_MKTAG(LFS_TYPE_DIRSTRUCT, 0, 8),
NULL,
lfs_fs_parent_match, &(struct lfs_fs_parent_match){
lfs, {pair[0], pair[1]}});
if (tag && tag != LFS_ERR_NOENT) {
return tag;
}
}
return LFS_ERR_NOENT;
}
#endif
static void lfs_fs_prepsuperblock(lfs_t *lfs, bool needssuperblock) {
lfs->gstate.tag = (lfs->gstate.tag & ~LFS_MKTAG(0, 0, 0x200))
| (uint32_t)needssuperblock << 9;
}
#ifndef LFS_READONLY
static int lfs_fs_preporphans(lfs_t *lfs, int8_t orphans) {
LFS_ASSERT(lfs_tag_size(lfs->gstate.tag) > 0x000 || orphans >= 0);
LFS_ASSERT(lfs_tag_size(lfs->gstate.tag) < 0x1ff || orphans <= 0);
lfs->gstate.tag += orphans;
lfs->gstate.tag = ((lfs->gstate.tag & ~LFS_MKTAG(0x800, 0, 0)) |
((uint32_t)lfs_gstate_hasorphans(&lfs->gstate) << 31));
return 0;
}
#endif
#ifndef LFS_READONLY
static void lfs_fs_prepmove(lfs_t *lfs,
uint16_t id, const lfs_block_t pair[2]) {
lfs->gstate.tag = ((lfs->gstate.tag & ~LFS_MKTAG(0x7ff, 0x3ff, 0)) |
((id != 0x3ff) ? LFS_MKTAG(LFS_TYPE_DELETE, id, 0) : 0));
lfs->gstate.pair[0] = (id != 0x3ff) ? pair[0] : 0;
lfs->gstate.pair[1] = (id != 0x3ff) ? pair[1] : 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_desuperblock(lfs_t *lfs) {
if (!lfs_gstate_needssuperblock(&lfs->gstate)) {
return 0;
}
LFS_DEBUG("Rewriting superblock {0x%"PRIx32", 0x%"PRIx32"}",
lfs->root[0],
lfs->root[1]);
lfs_mdir_t root;
int err = lfs_dir_fetch(lfs, &root, lfs->root);
if (err) {
return err;
}
// write a new superblock
lfs_superblock_t superblock = {
.version = lfs_fs_disk_version(lfs),
.block_size = lfs->cfg->block_size,
.block_count = lfs->block_count,
.name_max = lfs->name_max,
.file_max = lfs->file_max,
.attr_max = lfs->attr_max,
};
lfs_superblock_tole32(&superblock);
err = lfs_dir_commit(lfs, &root, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock}));
if (err) {
return err;
}
lfs_fs_prepsuperblock(lfs, false);
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_demove(lfs_t *lfs) {
if (!lfs_gstate_hasmove(&lfs->gdisk)) {
return 0;
}
// Fix bad moves
LFS_DEBUG("Fixing move {0x%"PRIx32", 0x%"PRIx32"} 0x%"PRIx16,
lfs->gdisk.pair[0],
lfs->gdisk.pair[1],
lfs_tag_id(lfs->gdisk.tag));
// no other gstate is supported at this time, so if we found something else
// something most likely went wrong in gstate calculation
LFS_ASSERT(lfs_tag_type3(lfs->gdisk.tag) == LFS_TYPE_DELETE);
// fetch and delete the moved entry
lfs_mdir_t movedir;
int err = lfs_dir_fetch(lfs, &movedir, lfs->gdisk.pair);
if (err) {
return err;
}
// prep gstate and delete move id
uint16_t moveid = lfs_tag_id(lfs->gdisk.tag);
lfs_fs_prepmove(lfs, 0x3ff, NULL);
err = lfs_dir_commit(lfs, &movedir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_DELETE, moveid, 0), NULL}));
if (err) {
return err;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_deorphan(lfs_t *lfs, bool powerloss) {
if (!lfs_gstate_hasorphans(&lfs->gstate)) {
return 0;
}
// Check for orphans in two separate passes:
// - 1 for half-orphans (relocations)
// - 2 for full-orphans (removes/renames)
//
// Two separate passes are needed as half-orphans can contain outdated
// references to full-orphans, effectively hiding them from the deorphan
// search.
//
int pass = 0;
while (pass < 2) {
// Fix any orphans
lfs_mdir_t pdir = {.split = true, .tail = {0, 1}};
lfs_mdir_t dir;
bool moreorphans = false;
// iterate over all directory directory entries
while (!lfs_pair_isnull(pdir.tail)) {
int err = lfs_dir_fetch(lfs, &dir, pdir.tail);
if (err) {
return err;
}
// check head blocks for orphans
if (!pdir.split) {
// check if we have a parent
lfs_mdir_t parent;
lfs_stag_t tag = lfs_fs_parent(lfs, pdir.tail, &parent);
if (tag < 0 && tag != LFS_ERR_NOENT) {
return tag;
}
if (pass == 0 && tag != LFS_ERR_NOENT) {
lfs_block_t pair[2];
lfs_stag_t state = lfs_dir_get(lfs, &parent,
LFS_MKTAG(0x7ff, 0x3ff, 0), tag, pair);
if (state < 0) {
return state;
}
lfs_pair_fromle32(pair);
if (!lfs_pair_issync(pair, pdir.tail)) {
// we have desynced
LFS_DEBUG("Fixing half-orphan "
"{0x%"PRIx32", 0x%"PRIx32"} "
"-> {0x%"PRIx32", 0x%"PRIx32"}",
pdir.tail[0], pdir.tail[1], pair[0], pair[1]);
// fix pending move in this pair? this looks like an
// optimization but is in fact _required_ since
// relocating may outdate the move.
uint16_t moveid = 0x3ff;
if (lfs_gstate_hasmovehere(&lfs->gstate, pdir.pair)) {
moveid = lfs_tag_id(lfs->gstate.tag);
LFS_DEBUG("Fixing move while fixing orphans "
"{0x%"PRIx32", 0x%"PRIx32"} 0x%"PRIx16"\n",
pdir.pair[0], pdir.pair[1], moveid);
lfs_fs_prepmove(lfs, 0x3ff, NULL);
}
lfs_pair_tole32(pair);
state = lfs_dir_orphaningcommit(lfs, &pdir, LFS_MKATTRS(
{LFS_MKTAG_IF(moveid != 0x3ff,
LFS_TYPE_DELETE, moveid, 0), NULL},
{LFS_MKTAG(LFS_TYPE_SOFTTAIL, 0x3ff, 8),
pair}));
lfs_pair_fromle32(pair);
if (state < 0) {
return state;
}
// did our commit create more orphans?
if (state == LFS_OK_ORPHANED) {
moreorphans = true;
}
// refetch tail
continue;
}
}
// note we only check for full orphans if we may have had a
// power-loss, otherwise orphans are created intentionally
// during operations such as lfs_mkdir
if (pass == 1 && tag == LFS_ERR_NOENT && powerloss) {
// we are an orphan
LFS_DEBUG("Fixing orphan {0x%"PRIx32", 0x%"PRIx32"}",
pdir.tail[0], pdir.tail[1]);
// steal state
err = lfs_dir_getgstate(lfs, &dir, &lfs->gdelta);
if (err) {
return err;
}
// steal tail
lfs_pair_tole32(dir.tail);
int state = lfs_dir_orphaningcommit(lfs, &pdir, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_TAIL + dir.split, 0x3ff, 8),
dir.tail}));
lfs_pair_fromle32(dir.tail);
if (state < 0) {
return state;
}
// did our commit create more orphans?
if (state == LFS_OK_ORPHANED) {
moreorphans = true;
}
// refetch tail
continue;
}
}
pdir = dir;
}
pass = moreorphans ? 0 : pass+1;
}
// mark orphans as fixed
return lfs_fs_preporphans(lfs, -lfs_gstate_getorphans(&lfs->gstate));
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_forceconsistency(lfs_t *lfs) {
int err = lfs_fs_desuperblock(lfs);
if (err) {
return err;
}
err = lfs_fs_demove(lfs);
if (err) {
return err;
}
err = lfs_fs_deorphan(lfs, true);
if (err) {
return err;
}
return 0;
}
#endif
#ifndef LFS_READONLY
static int lfs_fs_mkconsistent_(lfs_t *lfs) {
// lfs_fs_forceconsistency does most of the work here
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
// do we have any pending gstate?
lfs_gstate_t delta = {0};
lfs_gstate_xor(&delta, &lfs->gdisk);
lfs_gstate_xor(&delta, &lfs->gstate);
if (!lfs_gstate_iszero(&delta)) {
// lfs_dir_commit will implicitly write out any pending gstate
lfs_mdir_t root;
err = lfs_dir_fetch(lfs, &root, lfs->root);
if (err) {
return err;
}
err = lfs_dir_commit(lfs, &root, NULL, 0);
if (err) {
return err;
}
}
return 0;
}
#endif
static int lfs_fs_size_count(void *p, lfs_block_t block) {
(void)block;
lfs_size_t *size = p;
*size += 1;
return 0;
}
static lfs_ssize_t lfs_fs_size_(lfs_t *lfs) {
lfs_size_t size = 0;
int err = lfs_fs_traverse_(lfs, lfs_fs_size_count, &size, false);
if (err) {
return err;
}
return size;
}
// explicit garbage collection
#ifndef LFS_READONLY
static int lfs_fs_gc_(lfs_t *lfs) {
// force consistency, even if we're not necessarily going to write,
// because this function is supposed to take care of janitorial work
// isn't it?
int err = lfs_fs_forceconsistency(lfs);
if (err) {
return err;
}
// try to compact metadata pairs, note we can't really accomplish
// anything if compact_thresh doesn't at least leave a prog_size
// available
if (lfs->cfg->compact_thresh
< lfs->cfg->block_size - lfs->cfg->prog_size) {
// iterate over all mdirs
lfs_mdir_t mdir = {.tail = {0, 1}};
while (!lfs_pair_isnull(mdir.tail)) {
err = lfs_dir_fetch(lfs, &mdir, mdir.tail);
if (err) {
return err;
}
// not erased? exceeds our compaction threshold?
if (!mdir.erased || ((lfs->cfg->compact_thresh == 0)
? mdir.off > lfs->cfg->block_size - lfs->cfg->block_size/8
: mdir.off > lfs->cfg->compact_thresh)) {
// the easiest way to trigger a compaction is to mark
// the mdir as unerased and add an empty commit
mdir.erased = false;
err = lfs_dir_commit(lfs, &mdir, NULL, 0);
if (err) {
return err;
}
}
}
}
// try to populate the lookahead buffer, unless it's already full
if (lfs->lookahead.size < lfs_min(
8 * lfs->cfg->lookahead_size,
lfs->block_count)) {
err = lfs_alloc_scan(lfs);
if (err) {
return err;
}
}
return 0;
}
#endif
#ifndef LFS_READONLY
#ifdef LFS_SHRINKNONRELOCATING
static int lfs_shrink_checkblock(void *data, lfs_block_t block) {
lfs_size_t threshold = *((lfs_size_t*)data);
if (block >= threshold) {
return LFS_ERR_NOTEMPTY;
}
return 0;
}
#endif
static int lfs_fs_grow_(lfs_t *lfs, lfs_size_t block_count) {
int err;
if (block_count == lfs->block_count) {
return 0;
}
#ifndef LFS_SHRINKNONRELOCATING
// shrinking is not supported
LFS_ASSERT(block_count >= lfs->block_count);
#endif
#ifdef LFS_SHRINKNONRELOCATING
if (block_count < lfs->block_count) {
err = lfs_fs_traverse_(lfs, lfs_shrink_checkblock, &block_count, true);
if (err) {
return err;
}
}
#endif
lfs->block_count = block_count;
// fetch the root
lfs_mdir_t root;
err = lfs_dir_fetch(lfs, &root, lfs->root);
if (err) {
return err;
}
// update the superblock
lfs_superblock_t superblock;
lfs_stag_t tag = lfs_dir_get(lfs, &root, LFS_MKTAG(0x7ff, 0x3ff, 0),
LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock);
if (tag < 0) {
return tag;
}
lfs_superblock_fromle32(&superblock);
superblock.block_count = lfs->block_count;
lfs_superblock_tole32(&superblock);
err = lfs_dir_commit(lfs, &root, LFS_MKATTRS(
{tag, &superblock}));
if (err) {
return err;
}
return 0;
}
#endif
#ifdef LFS_MIGRATE
////// Migration from littelfs v1 below this //////
/// Version info ///
// Software library version
// Major (top-nibble), incremented on backwards incompatible changes
// Minor (bottom-nibble), incremented on feature additions
#define LFS1_VERSION 0x00010007
#define LFS1_VERSION_MAJOR (0xffff & (LFS1_VERSION >> 16))
#define LFS1_VERSION_MINOR (0xffff & (LFS1_VERSION >> 0))
// Version of On-disk data structures
// Major (top-nibble), incremented on backwards incompatible changes
// Minor (bottom-nibble), incremented on feature additions
#define LFS1_DISK_VERSION 0x00010001
#define LFS1_DISK_VERSION_MAJOR (0xffff & (LFS1_DISK_VERSION >> 16))
#define LFS1_DISK_VERSION_MINOR (0xffff & (LFS1_DISK_VERSION >> 0))
/// v1 Definitions ///
// File types
enum lfs1_type {
LFS1_TYPE_REG = 0x11,
LFS1_TYPE_DIR = 0x22,
LFS1_TYPE_SUPERBLOCK = 0x2e,
};
typedef struct lfs1 {
lfs_block_t root[2];
} lfs1_t;
typedef struct lfs1_entry {
lfs_off_t off;
struct lfs1_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;
} lfs1_entry_t;
typedef struct lfs1_dir {
struct lfs1_dir *next;
lfs_block_t pair[2];
lfs_off_t off;
lfs_block_t head[2];
lfs_off_t pos;
struct lfs1_disk_dir {
uint32_t rev;
lfs_size_t size;
lfs_block_t tail[2];
} d;
} lfs1_dir_t;
typedef struct lfs1_superblock {
lfs_off_t off;
struct lfs1_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;
} lfs1_superblock_t;
/// Low-level wrappers v1->v2 ///
static void lfs1_crc(uint32_t *crc, const void *buffer, size_t size) {
*crc = lfs_crc(*crc, buffer, size);
}
static int lfs1_bd_read(lfs_t *lfs, lfs_block_t block,
lfs_off_t off, void *buffer, lfs_size_t size) {
// if we ever do more than writes to alternating pairs,
// this may need to consider pcache
return lfs_bd_read(lfs, &lfs->pcache, &lfs->rcache, size,
block, off, buffer, size);
}
static int lfs1_bd_crc(lfs_t *lfs, lfs_block_t block,
lfs_off_t off, lfs_size_t size, uint32_t *crc) {
for (lfs_off_t i = 0; i < size; i++) {
uint8_t c;
int err = lfs1_bd_read(lfs, block, off+i, &c, 1);
if (err) {
return err;
}
lfs1_crc(crc, &c, 1);
}
return 0;
}
/// Endian swapping functions ///
static void lfs1_dir_fromle32(struct lfs1_disk_dir *d) {
d->rev = lfs_fromle32(d->rev);
d->size = lfs_fromle32(d->size);
d->tail[0] = lfs_fromle32(d->tail[0]);
d->tail[1] = lfs_fromle32(d->tail[1]);
}
static void lfs1_dir_tole32(struct lfs1_disk_dir *d) {
d->rev = lfs_tole32(d->rev);
d->size = lfs_tole32(d->size);
d->tail[0] = lfs_tole32(d->tail[0]);
d->tail[1] = lfs_tole32(d->tail[1]);
}
static void lfs1_entry_fromle32(struct lfs1_disk_entry *d) {
d->u.dir[0] = lfs_fromle32(d->u.dir[0]);
d->u.dir[1] = lfs_fromle32(d->u.dir[1]);
}
static void lfs1_entry_tole32(struct lfs1_disk_entry *d) {
d->u.dir[0] = lfs_tole32(d->u.dir[0]);
d->u.dir[1] = lfs_tole32(d->u.dir[1]);
}
static void lfs1_superblock_fromle32(struct lfs1_disk_superblock *d) {
d->root[0] = lfs_fromle32(d->root[0]);
d->root[1] = lfs_fromle32(d->root[1]);
d->block_size = lfs_fromle32(d->block_size);
d->block_count = lfs_fromle32(d->block_count);
d->version = lfs_fromle32(d->version);
}
///// Metadata pair and directory operations ///
static inline lfs_size_t lfs1_entry_size(const lfs1_entry_t *entry) {
return 4 + entry->d.elen + entry->d.alen + entry->d.nlen;
}
static int lfs1_dir_fetch(lfs_t *lfs,
lfs1_dir_t *dir, const lfs_block_t pair[2]) {
// copy out pair, otherwise may be aliasing dir
const lfs_block_t tpair[2] = {pair[0], pair[1]};
bool valid = false;
// check both blocks for the most recent revision
for (int i = 0; i < 2; i++) {
struct lfs1_disk_dir test;
int err = lfs1_bd_read(lfs, tpair[i], 0, &test, sizeof(test));
lfs1_dir_fromle32(&test);
if (err) {
if (err == LFS_ERR_CORRUPT) {
continue;
}
return err;
}
if (valid && lfs_scmp(test.rev, dir->d.rev) < 0) {
continue;
}
if ((0x7fffffff & test.size) < sizeof(test)+4 ||
(0x7fffffff & test.size) > lfs->cfg->block_size) {
continue;
}
uint32_t crc = 0xffffffff;
lfs1_dir_tole32(&test);
lfs1_crc(&crc, &test, sizeof(test));
lfs1_dir_fromle32(&test);
err = lfs1_bd_crc(lfs, tpair[i], sizeof(test),
(0x7fffffff & test.size) - sizeof(test), &crc);
if (err) {
if (err == LFS_ERR_CORRUPT) {
continue;
}
return err;
}
if (crc != 0) {
continue;
}
valid = true;
// setup dir in case it's valid
dir->pair[0] = tpair[(i+0) % 2];
dir->pair[1] = tpair[(i+1) % 2];
dir->off = sizeof(dir->d);
dir->d = test;
}
if (!valid) {
LFS_ERROR("Corrupted dir pair at {0x%"PRIx32", 0x%"PRIx32"}",
tpair[0], tpair[1]);
return LFS_ERR_CORRUPT;
}
return 0;
}
static int lfs1_dir_next(lfs_t *lfs, lfs1_dir_t *dir, lfs1_entry_t *entry) {
while (dir->off + sizeof(entry->d) > (0x7fffffff & dir->d.size)-4) {
if (!(0x80000000 & dir->d.size)) {
entry->off = dir->off;
return LFS_ERR_NOENT;
}
int err = lfs1_dir_fetch(lfs, dir, dir->d.tail);
if (err) {
return err;
}
dir->off = sizeof(dir->d);
dir->pos += sizeof(dir->d) + 4;
}
int err = lfs1_bd_read(lfs, dir->pair[0], dir->off,
&entry->d, sizeof(entry->d));
lfs1_entry_fromle32(&entry->d);
if (err) {
return err;
}
entry->off = dir->off;
dir->off += lfs1_entry_size(entry);
dir->pos += lfs1_entry_size(entry);
return 0;
}
/// littlefs v1 specific operations ///
int lfs1_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data) {
if (lfs_pair_isnull(lfs->lfs1->root)) {
return 0;
}
// iterate over metadata pairs
lfs1_dir_t dir;
lfs1_entry_t entry;
lfs_block_t cwd[2] = {0, 1};
while (true) {
for (int i = 0; i < 2; i++) {
int err = cb(data, cwd[i]);
if (err) {
return err;
}
}
int err = lfs1_dir_fetch(lfs, &dir, cwd);
if (err) {
return err;
}
// iterate over contents
while (dir.off + sizeof(entry.d) <= (0x7fffffff & dir.d.size)-4) {
err = lfs1_bd_read(lfs, dir.pair[0], dir.off,
&entry.d, sizeof(entry.d));
lfs1_entry_fromle32(&entry.d);
if (err) {
return err;
}
dir.off += lfs1_entry_size(&entry);
if ((0x70 & entry.d.type) == (0x70 & LFS1_TYPE_REG)) {
err = lfs_ctz_traverse(lfs, NULL, &lfs->rcache,
entry.d.u.file.head, entry.d.u.file.size, cb, data);
if (err) {
return err;
}
}
}
// we also need to check if we contain a threaded v2 directory
lfs_mdir_t dir2 = {.split=true, .tail={cwd[0], cwd[1]}};
while (dir2.split) {
err = lfs_dir_fetch(lfs, &dir2, dir2.tail);
if (err) {
break;
}
for (int i = 0; i < 2; i++) {
err = cb(data, dir2.pair[i]);
if (err) {
return err;
}
}
}
cwd[0] = dir.d.tail[0];
cwd[1] = dir.d.tail[1];
if (lfs_pair_isnull(cwd)) {
break;
}
}
return 0;
}
static int lfs1_moved(lfs_t *lfs, const void *e) {
if (lfs_pair_isnull(lfs->lfs1->root)) {
return 0;
}
// skip superblock
lfs1_dir_t cwd;
int err = lfs1_dir_fetch(lfs, &cwd, (const lfs_block_t[2]){0, 1});
if (err) {
return err;
}
// iterate over all directory directory entries
lfs1_entry_t entry;
while (!lfs_pair_isnull(cwd.d.tail)) {
err = lfs1_dir_fetch(lfs, &cwd, cwd.d.tail);
if (err) {
return err;
}
while (true) {
err = lfs1_dir_next(lfs, &cwd, &entry);
if (err && err != LFS_ERR_NOENT) {
return err;
}
if (err == LFS_ERR_NOENT) {
break;
}
if (!(0x80 & entry.d.type) &&
memcmp(&entry.d.u, e, sizeof(entry.d.u)) == 0) {
return true;
}
}
}
return false;
}
/// Filesystem operations ///
static int lfs1_mount(lfs_t *lfs, struct lfs1 *lfs1,
const struct lfs_config *cfg) {
int err = 0;
{
err = lfs_init(lfs, cfg);
if (err) {
return err;
}
lfs->lfs1 = lfs1;
lfs->lfs1->root[0] = LFS_BLOCK_NULL;
lfs->lfs1->root[1] = LFS_BLOCK_NULL;
// setup free lookahead
lfs->lookahead.start = 0;
lfs->lookahead.size = 0;
lfs->lookahead.next = 0;
lfs_alloc_ckpoint(lfs);
// load superblock
lfs1_dir_t dir;
lfs1_superblock_t superblock;
err = lfs1_dir_fetch(lfs, &dir, (const lfs_block_t[2]){0, 1});
if (err && err != LFS_ERR_CORRUPT) {
goto cleanup;
}
if (!err) {
err = lfs1_bd_read(lfs, dir.pair[0], sizeof(dir.d),
&superblock.d, sizeof(superblock.d));
lfs1_superblock_fromle32(&superblock.d);
if (err) {
goto cleanup;
}
lfs->lfs1->root[0] = superblock.d.root[0];
lfs->lfs1->root[1] = superblock.d.root[1];
}
if (err || memcmp(superblock.d.magic, "littlefs", 8) != 0) {
LFS_ERROR("Invalid superblock at {0x%"PRIx32", 0x%"PRIx32"}",
0, 1);
err = LFS_ERR_CORRUPT;
goto cleanup;
}
uint16_t major_version = (0xffff & (superblock.d.version >> 16));
uint16_t minor_version = (0xffff & (superblock.d.version >> 0));
if ((major_version != LFS1_DISK_VERSION_MAJOR ||
minor_version > LFS1_DISK_VERSION_MINOR)) {
LFS_ERROR("Invalid version v%d.%d", major_version, minor_version);
err = LFS_ERR_INVAL;
goto cleanup;
}
return 0;
}
cleanup:
lfs_deinit(lfs);
return err;
}
static int lfs1_unmount(lfs_t *lfs) {
return lfs_deinit(lfs);
}
/// v1 migration ///
static int lfs_migrate_(lfs_t *lfs, const struct lfs_config *cfg) {
struct lfs1 lfs1;
// Indeterminate filesystem size not allowed for migration.
LFS_ASSERT(cfg->block_count != 0);
int err = lfs1_mount(lfs, &lfs1, cfg);
if (err) {
return err;
}
{
// iterate through each directory, copying over entries
// into new directory
lfs1_dir_t dir1;
lfs_mdir_t dir2;
dir1.d.tail[0] = lfs->lfs1->root[0];
dir1.d.tail[1] = lfs->lfs1->root[1];
while (!lfs_pair_isnull(dir1.d.tail)) {
// iterate old dir
err = lfs1_dir_fetch(lfs, &dir1, dir1.d.tail);
if (err) {
goto cleanup;
}
// create new dir and bind as temporary pretend root
err = lfs_dir_alloc(lfs, &dir2);
if (err) {
goto cleanup;
}
dir2.rev = dir1.d.rev;
dir1.head[0] = dir1.pair[0];
dir1.head[1] = dir1.pair[1];
lfs->root[0] = dir2.pair[0];
lfs->root[1] = dir2.pair[1];
err = lfs_dir_commit(lfs, &dir2, NULL, 0);
if (err) {
goto cleanup;
}
while (true) {
lfs1_entry_t entry1;
err = lfs1_dir_next(lfs, &dir1, &entry1);
if (err && err != LFS_ERR_NOENT) {
goto cleanup;
}
if (err == LFS_ERR_NOENT) {
break;
}
// check that entry has not been moved
if (entry1.d.type & 0x80) {
int moved = lfs1_moved(lfs, &entry1.d.u);
if (moved < 0) {
err = moved;
goto cleanup;
}
if (moved) {
continue;
}
entry1.d.type &= ~0x80;
}
// also fetch name
char name[LFS_NAME_MAX+1];
memset(name, 0, sizeof(name));
err = lfs1_bd_read(lfs, dir1.pair[0],
entry1.off + 4+entry1.d.elen+entry1.d.alen,
name, entry1.d.nlen);
if (err) {
goto cleanup;
}
bool isdir = (entry1.d.type == LFS1_TYPE_DIR);
// create entry in new dir
err = lfs_dir_fetch(lfs, &dir2, lfs->root);
if (err) {
goto cleanup;
}
uint16_t id;
err = lfs_dir_find(lfs, &dir2, &(const char*){name}, &id);
if (!(err == LFS_ERR_NOENT && id != 0x3ff)) {
err = (err < 0) ? err : LFS_ERR_EXIST;
goto cleanup;
}
lfs1_entry_tole32(&entry1.d);
err = lfs_dir_commit(lfs, &dir2, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_CREATE, id, 0), NULL},
{LFS_MKTAG_IF_ELSE(isdir,
LFS_TYPE_DIR, id, entry1.d.nlen,
LFS_TYPE_REG, id, entry1.d.nlen),
name},
{LFS_MKTAG_IF_ELSE(isdir,
LFS_TYPE_DIRSTRUCT, id, sizeof(entry1.d.u),
LFS_TYPE_CTZSTRUCT, id, sizeof(entry1.d.u)),
&entry1.d.u}));
lfs1_entry_fromle32(&entry1.d);
if (err) {
goto cleanup;
}
}
if (!lfs_pair_isnull(dir1.d.tail)) {
// find last block and update tail to thread into fs
err = lfs_dir_fetch(lfs, &dir2, lfs->root);
if (err) {
goto cleanup;
}
while (dir2.split) {
err = lfs_dir_fetch(lfs, &dir2, dir2.tail);
if (err) {
goto cleanup;
}
}
lfs_pair_tole32(dir2.pair);
err = lfs_dir_commit(lfs, &dir2, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_SOFTTAIL, 0x3ff, 8), dir1.d.tail}));
lfs_pair_fromle32(dir2.pair);
if (err) {
goto cleanup;
}
}
// Copy over first block to thread into fs. Unfortunately
// if this fails there is not much we can do.
LFS_DEBUG("Migrating {0x%"PRIx32", 0x%"PRIx32"} "
"-> {0x%"PRIx32", 0x%"PRIx32"}",
lfs->root[0], lfs->root[1], dir1.head[0], dir1.head[1]);
err = lfs_bd_erase(lfs, dir1.head[1]);
if (err) {
goto cleanup;
}
err = lfs_dir_fetch(lfs, &dir2, lfs->root);
if (err) {
goto cleanup;
}
for (lfs_off_t i = 0; i < dir2.off; i++) {
uint8_t dat;
err = lfs_bd_read(lfs,
NULL, &lfs->rcache, dir2.off,
dir2.pair[0], i, &dat, 1);
if (err) {
goto cleanup;
}
err = lfs_bd_prog(lfs,
&lfs->pcache, &lfs->rcache, true,
dir1.head[1], i, &dat, 1);
if (err) {
goto cleanup;
}
}
err = lfs_bd_flush(lfs, &lfs->pcache, &lfs->rcache, true);
if (err) {
goto cleanup;
}
}
// Create new superblock. This marks a successful migration!
err = lfs1_dir_fetch(lfs, &dir1, (const lfs_block_t[2]){0, 1});
if (err) {
goto cleanup;
}
dir2.pair[0] = dir1.pair[0];
dir2.pair[1] = dir1.pair[1];
dir2.rev = dir1.d.rev;
dir2.off = sizeof(dir2.rev);
dir2.etag = 0xffffffff;
dir2.count = 0;
dir2.tail[0] = lfs->lfs1->root[0];
dir2.tail[1] = lfs->lfs1->root[1];
dir2.erased = false;
dir2.split = true;
lfs_superblock_t superblock = {
.version = LFS_DISK_VERSION,
.block_size = lfs->cfg->block_size,
.block_count = lfs->cfg->block_count,
.name_max = lfs->name_max,
.file_max = lfs->file_max,
.attr_max = lfs->attr_max,
};
lfs_superblock_tole32(&superblock);
err = lfs_dir_commit(lfs, &dir2, LFS_MKATTRS(
{LFS_MKTAG(LFS_TYPE_CREATE, 0, 0), NULL},
{LFS_MKTAG(LFS_TYPE_SUPERBLOCK, 0, 8), "littlefs"},
{LFS_MKTAG(LFS_TYPE_INLINESTRUCT, 0, sizeof(superblock)),
&superblock}));
if (err) {
goto cleanup;
}
// sanity check that fetch works
err = lfs_dir_fetch(lfs, &dir2, (const lfs_block_t[2]){0, 1});
if (err) {
goto cleanup;
}
// force compaction to prevent accidentally mounting v1
dir2.erased = false;
err = lfs_dir_commit(lfs, &dir2, NULL, 0);
if (err) {
goto cleanup;
}
}
cleanup:
lfs1_unmount(lfs);
return err;
}
#endif
/// Public API wrappers ///
// Here we can add tracing/thread safety easily
// Thread-safe wrappers if enabled
#ifdef LFS_THREADSAFE
#define LFS_LOCK(cfg) cfg->lock(cfg)
#define LFS_UNLOCK(cfg) cfg->unlock(cfg)
#else
#define LFS_LOCK(cfg) ((void)cfg, 0)
#define LFS_UNLOCK(cfg) ((void)cfg)
#endif
// Public API
#ifndef LFS_READONLY
int lfs_format(lfs_t *lfs, const struct lfs_config *cfg) {
int err = LFS_LOCK(cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_format(%p, %p {.context=%p, "
".read=%p, .prog=%p, .erase=%p, .sync=%p, "
".read_size=%"PRIu32", .prog_size=%"PRIu32", "
".block_size=%"PRIu32", .block_count=%"PRIu32", "
".block_cycles=%"PRId32", .cache_size=%"PRIu32", "
".lookahead_size=%"PRIu32", .read_buffer=%p, "
".prog_buffer=%p, .lookahead_buffer=%p, "
".name_max=%"PRIu32", .file_max=%"PRIu32", "
".attr_max=%"PRIu32"})",
(void*)lfs, (void*)cfg, cfg->context,
(void*)(uintptr_t)cfg->read, (void*)(uintptr_t)cfg->prog,
(void*)(uintptr_t)cfg->erase, (void*)(uintptr_t)cfg->sync,
cfg->read_size, cfg->prog_size, cfg->block_size, cfg->block_count,
cfg->block_cycles, cfg->cache_size, cfg->lookahead_size,
cfg->read_buffer, cfg->prog_buffer, cfg->lookahead_buffer,
cfg->name_max, cfg->file_max, cfg->attr_max);
err = lfs_format_(lfs, cfg);
LFS_TRACE("lfs_format -> %d", err);
LFS_UNLOCK(cfg);
return err;
}
#endif
int lfs_mount(lfs_t *lfs, const struct lfs_config *cfg) {
int err = LFS_LOCK(cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_mount(%p, %p {.context=%p, "
".read=%p, .prog=%p, .erase=%p, .sync=%p, "
".read_size=%"PRIu32", .prog_size=%"PRIu32", "
".block_size=%"PRIu32", .block_count=%"PRIu32", "
".block_cycles=%"PRId32", .cache_size=%"PRIu32", "
".lookahead_size=%"PRIu32", .read_buffer=%p, "
".prog_buffer=%p, .lookahead_buffer=%p, "
".name_max=%"PRIu32", .file_max=%"PRIu32", "
".attr_max=%"PRIu32"})",
(void*)lfs, (void*)cfg, cfg->context,
(void*)(uintptr_t)cfg->read, (void*)(uintptr_t)cfg->prog,
(void*)(uintptr_t)cfg->erase, (void*)(uintptr_t)cfg->sync,
cfg->read_size, cfg->prog_size, cfg->block_size, cfg->block_count,
cfg->block_cycles, cfg->cache_size, cfg->lookahead_size,
cfg->read_buffer, cfg->prog_buffer, cfg->lookahead_buffer,
cfg->name_max, cfg->file_max, cfg->attr_max);
err = lfs_mount_(lfs, cfg);
LFS_TRACE("lfs_mount -> %d", err);
LFS_UNLOCK(cfg);
return err;
}
int lfs_unmount(lfs_t *lfs) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_unmount(%p)", (void*)lfs);
err = lfs_unmount_(lfs);
LFS_TRACE("lfs_unmount -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#ifndef LFS_READONLY
int lfs_remove(lfs_t *lfs, const char *path) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_remove(%p, \"%s\")", (void*)lfs, path);
err = lfs_remove_(lfs, path);
LFS_TRACE("lfs_remove -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifndef LFS_READONLY
int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_rename(%p, \"%s\", \"%s\")", (void*)lfs, oldpath, newpath);
err = lfs_rename_(lfs, oldpath, newpath);
LFS_TRACE("lfs_rename -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
int lfs_stat(lfs_t *lfs, const char *path, struct lfs_info *info) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_stat(%p, \"%s\", %p)", (void*)lfs, path, (void*)info);
err = lfs_stat_(lfs, path, info);
LFS_TRACE("lfs_stat -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
lfs_ssize_t lfs_getattr(lfs_t *lfs, const char *path,
uint8_t type, void *buffer, lfs_size_t size) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_getattr(%p, \"%s\", %"PRIu8", %p, %"PRIu32")",
(void*)lfs, path, type, buffer, size);
lfs_ssize_t res = lfs_getattr_(lfs, path, type, buffer, size);
LFS_TRACE("lfs_getattr -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
#ifndef LFS_READONLY
int lfs_setattr(lfs_t *lfs, const char *path,
uint8_t type, const void *buffer, lfs_size_t size) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_setattr(%p, \"%s\", %"PRIu8", %p, %"PRIu32")",
(void*)lfs, path, type, buffer, size);
err = lfs_setattr_(lfs, path, type, buffer, size);
LFS_TRACE("lfs_setattr -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifndef LFS_READONLY
int lfs_removeattr(lfs_t *lfs, const char *path, uint8_t type) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_removeattr(%p, \"%s\", %"PRIu8")", (void*)lfs, path, type);
err = lfs_removeattr_(lfs, path, type);
LFS_TRACE("lfs_removeattr -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifndef LFS_NO_MALLOC
int lfs_file_open(lfs_t *lfs, lfs_file_t *file, const char *path, int flags) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_open(%p, %p, \"%s\", %x)",
(void*)lfs, (void*)file, path, (unsigned)flags);
LFS_ASSERT(!lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
err = lfs_file_open_(lfs, file, path, flags);
LFS_TRACE("lfs_file_open -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
int lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file,
const char *path, int flags,
const struct lfs_file_config *cfg) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_opencfg(%p, %p, \"%s\", %x, %p {"
".buffer=%p, .attrs=%p, .attr_count=%"PRIu32"})",
(void*)lfs, (void*)file, path, (unsigned)flags,
(void*)cfg, cfg->buffer, (void*)cfg->attrs, cfg->attr_count);
LFS_ASSERT(!lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
err = lfs_file_opencfg_(lfs, file, path, flags, cfg);
LFS_TRACE("lfs_file_opencfg -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
int lfs_file_close(lfs_t *lfs, lfs_file_t *file) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_close(%p, %p)", (void*)lfs, (void*)file);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
err = lfs_file_close_(lfs, file);
LFS_TRACE("lfs_file_close -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#ifndef LFS_READONLY
int lfs_file_sync(lfs_t *lfs, lfs_file_t *file) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_sync(%p, %p)", (void*)lfs, (void*)file);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
err = lfs_file_sync_(lfs, file);
LFS_TRACE("lfs_file_sync -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
lfs_ssize_t lfs_file_read(lfs_t *lfs, lfs_file_t *file,
void *buffer, lfs_size_t size) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_read(%p, %p, %p, %"PRIu32")",
(void*)lfs, (void*)file, buffer, size);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
lfs_ssize_t res = lfs_file_read_(lfs, file, buffer, size);
LFS_TRACE("lfs_file_read -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
#ifndef LFS_READONLY
lfs_ssize_t lfs_file_write(lfs_t *lfs, lfs_file_t *file,
const void *buffer, lfs_size_t size) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_write(%p, %p, %p, %"PRIu32")",
(void*)lfs, (void*)file, buffer, size);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
lfs_ssize_t res = lfs_file_write_(lfs, file, buffer, size);
LFS_TRACE("lfs_file_write -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
#endif
lfs_soff_t lfs_file_seek(lfs_t *lfs, lfs_file_t *file,
lfs_soff_t off, int whence) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_seek(%p, %p, %"PRId32", %d)",
(void*)lfs, (void*)file, off, whence);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
lfs_soff_t res = lfs_file_seek_(lfs, file, off, whence);
LFS_TRACE("lfs_file_seek -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
#ifndef LFS_READONLY
int lfs_file_truncate(lfs_t *lfs, lfs_file_t *file, lfs_off_t size) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_truncate(%p, %p, %"PRIu32")",
(void*)lfs, (void*)file, size);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
err = lfs_file_truncate_(lfs, file, size);
LFS_TRACE("lfs_file_truncate -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
lfs_soff_t lfs_file_tell(lfs_t *lfs, lfs_file_t *file) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_tell(%p, %p)", (void*)lfs, (void*)file);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
lfs_soff_t res = lfs_file_tell_(lfs, file);
LFS_TRACE("lfs_file_tell -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
int lfs_file_rewind(lfs_t *lfs, lfs_file_t *file) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_rewind(%p, %p)", (void*)lfs, (void*)file);
err = lfs_file_rewind_(lfs, file);
LFS_TRACE("lfs_file_rewind -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
lfs_soff_t lfs_file_size(lfs_t *lfs, lfs_file_t *file) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_file_size(%p, %p)", (void*)lfs, (void*)file);
LFS_ASSERT(lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)file));
lfs_soff_t res = lfs_file_size_(lfs, file);
LFS_TRACE("lfs_file_size -> %"PRIu32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
#ifndef LFS_READONLY
int lfs_mkdir(lfs_t *lfs, const char *path) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_mkdir(%p, \"%s\")", (void*)lfs, path);
err = lfs_mkdir_(lfs, path);
LFS_TRACE("lfs_mkdir -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
int lfs_dir_open(lfs_t *lfs, lfs_dir_t *dir, const char *path) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_open(%p, %p, \"%s\")", (void*)lfs, (void*)dir, path);
LFS_ASSERT(!lfs_mlist_isopen(lfs->mlist, (struct lfs_mlist*)dir));
err = lfs_dir_open_(lfs, dir, path);
LFS_TRACE("lfs_dir_open -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
int lfs_dir_close(lfs_t *lfs, lfs_dir_t *dir) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_close(%p, %p)", (void*)lfs, (void*)dir);
err = lfs_dir_close_(lfs, dir);
LFS_TRACE("lfs_dir_close -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
int lfs_dir_read(lfs_t *lfs, lfs_dir_t *dir, struct lfs_info *info) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_read(%p, %p, %p)",
(void*)lfs, (void*)dir, (void*)info);
err = lfs_dir_read_(lfs, dir, info);
LFS_TRACE("lfs_dir_read -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
int lfs_dir_seek(lfs_t *lfs, lfs_dir_t *dir, lfs_off_t off) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_seek(%p, %p, %"PRIu32")",
(void*)lfs, (void*)dir, off);
err = lfs_dir_seek_(lfs, dir, off);
LFS_TRACE("lfs_dir_seek -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
lfs_soff_t lfs_dir_tell(lfs_t *lfs, lfs_dir_t *dir) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_tell(%p, %p)", (void*)lfs, (void*)dir);
lfs_soff_t res = lfs_dir_tell_(lfs, dir);
LFS_TRACE("lfs_dir_tell -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
int lfs_dir_rewind(lfs_t *lfs, lfs_dir_t *dir) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_dir_rewind(%p, %p)", (void*)lfs, (void*)dir);
err = lfs_dir_rewind_(lfs, dir);
LFS_TRACE("lfs_dir_rewind -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
int lfs_fs_stat(lfs_t *lfs, struct lfs_fsinfo *fsinfo) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_stat(%p, %p)", (void*)lfs, (void*)fsinfo);
err = lfs_fs_stat_(lfs, fsinfo);
LFS_TRACE("lfs_fs_stat -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
lfs_ssize_t lfs_fs_size(lfs_t *lfs) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_size(%p)", (void*)lfs);
lfs_ssize_t res = lfs_fs_size_(lfs);
LFS_TRACE("lfs_fs_size -> %"PRId32, res);
LFS_UNLOCK(lfs->cfg);
return res;
}
int lfs_fs_traverse(lfs_t *lfs, int (*cb)(void *, lfs_block_t), void *data) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_traverse(%p, %p, %p)",
(void*)lfs, (void*)(uintptr_t)cb, data);
err = lfs_fs_traverse_(lfs, cb, data, true);
LFS_TRACE("lfs_fs_traverse -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#ifndef LFS_READONLY
int lfs_fs_mkconsistent(lfs_t *lfs) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_mkconsistent(%p)", (void*)lfs);
err = lfs_fs_mkconsistent_(lfs);
LFS_TRACE("lfs_fs_mkconsistent -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifndef LFS_READONLY
int lfs_fs_gc(lfs_t *lfs) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_gc(%p)", (void*)lfs);
err = lfs_fs_gc_(lfs);
LFS_TRACE("lfs_fs_gc -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifndef LFS_READONLY
int lfs_fs_grow(lfs_t *lfs, lfs_size_t block_count) {
int err = LFS_LOCK(lfs->cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_fs_grow(%p, %"PRIu32")", (void*)lfs, block_count);
err = lfs_fs_grow_(lfs, block_count);
LFS_TRACE("lfs_fs_grow -> %d", err);
LFS_UNLOCK(lfs->cfg);
return err;
}
#endif
#ifdef LFS_MIGRATE
int lfs_migrate(lfs_t *lfs, const struct lfs_config *cfg) {
int err = LFS_LOCK(cfg);
if (err) {
return err;
}
LFS_TRACE("lfs_migrate(%p, %p {.context=%p, "
".read=%p, .prog=%p, .erase=%p, .sync=%p, "
".read_size=%"PRIu32", .prog_size=%"PRIu32", "
".block_size=%"PRIu32", .block_count=%"PRIu32", "
".block_cycles=%"PRId32", .cache_size=%"PRIu32", "
".lookahead_size=%"PRIu32", .read_buffer=%p, "
".prog_buffer=%p, .lookahead_buffer=%p, "
".name_max=%"PRIu32", .file_max=%"PRIu32", "
".attr_max=%"PRIu32"})",
(void*)lfs, (void*)cfg, cfg->context,
(void*)(uintptr_t)cfg->read, (void*)(uintptr_t)cfg->prog,
(void*)(uintptr_t)cfg->erase, (void*)(uintptr_t)cfg->sync,
cfg->read_size, cfg->prog_size, cfg->block_size, cfg->block_count,
cfg->block_cycles, cfg->cache_size, cfg->lookahead_size,
cfg->read_buffer, cfg->prog_buffer, cfg->lookahead_buffer,
cfg->name_max, cfg->file_max, cfg->attr_max);
err = lfs_migrate_(lfs, cfg);
LFS_TRACE("lfs_migrate -> %d", err);
LFS_UNLOCK(cfg);
return err;
}
#endif