nuttx/fs/littlefs/lfs.c

3441 lines
76 KiB
C

/****************************************************************************
* fs/littlefs/lfs.c
*
* This file is a part of NuttX:
*
* Copyright (C) 2019 Gregory Nutt. All rights reserved.
*
* Ported by:
*
* Copyright (C) 2019 Pinecone Inc. All rights reserved.
* Author: lihaichen <li8303@163.com>
*
* This port derives from ARM mbed logic which has a compatible 3-clause
* BSD license:
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the names ARM, NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <inttypes.h>
#include "lfs.h"
#include "lfs_util.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
struct lfs_region_s
{
lfs_off_t oldoff;
lfs_size_t oldlen;
FAR const void *newdata;
lfs_size_t newlen;
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int lfs_pred(FAR lfs_t *lfs, FAR const lfs_block_t dir[2],
FAR lfs_dir_t *pdir);
static int lfs_parent(FAR lfs_t *lfs, FAR const lfs_block_t dir[2],
FAR lfs_dir_t *parent, FAR lfs_entry_t *entry);
static int lfs_moved(FAR lfs_t *lfs, FAR const void *e);
static int lfs_relocate(FAR lfs_t *lfs, FAR const lfs_block_t oldpair[2],
FAR const lfs_block_t newpair[2]);
/****************************************************************************
* Private Functions
****************************************************************************/
/* Caching block device operations */
static int lfs_cache_read(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR const lfs_cache_t *pcache, lfs_block_t block,
lfs_off_t off, FAR void *buffer, lfs_size_t size)
{
FAR uint8_t *data = buffer;
LFS_ASSERT(block < lfs->cfg->block_count);
while (size > 0)
{
if (pcache && block == pcache->block && off >= pcache->off &&
off < pcache->off + lfs->cfg->prog_size)
{
/* is already in pcache? */
lfs_size_t diff =
lfs_min(size, lfs->cfg->prog_size - (off - pcache->off));
memcpy(data, &pcache->buffer[off - pcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
if (block == rcache->block && off >= rcache->off &&
off < rcache->off + lfs->cfg->read_size)
{
/* is already in rcache? */
lfs_size_t diff =
lfs_min(size, lfs->cfg->read_size - (off - rcache->off));
memcpy(data, &rcache->buffer[off - rcache->off], diff);
data += diff;
off += diff;
size -= diff;
continue;
}
if (off % lfs->cfg->read_size == 0 && size >= lfs->cfg->read_size)
{
/* bypass cache? */
lfs_size_t diff = size - (size % lfs->cfg->read_size);
int err = lfs->cfg->read(lfs->cfg, block, off, data, diff);
if (err)
{
return err;
}
data += diff;
off += diff;
size -= diff;
continue;
}
/* load to cache, first condition can no longer fail */
rcache->block = block;
rcache->off = off - (off % lfs->cfg->read_size);
int err = lfs->cfg->read(lfs->cfg, rcache->block, rcache->off,
rcache->buffer, lfs->cfg->read_size);
if (err)
{
return err;
}
}
return 0;
}
static int lfs_cache_cmp(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR const lfs_cache_t *pcache, lfs_block_t block,
lfs_off_t off, FAR const void *buffer,
lfs_size_t size)
{
FAR const uint8_t *data = buffer;
lfs_off_t i;
for (i = 0; i < size; i++)
{
uint8_t c;
int err = lfs_cache_read(lfs, rcache, pcache, block, off + i, &c, 1);
if (err)
{
return err;
}
if (c != data[i])
{
return false;
}
}
return true;
}
static int lfs_cache_crc(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR const lfs_cache_t *pcache, lfs_block_t block,
lfs_off_t off, lfs_size_t size, FAR uint32_t *crc)
{
lfs_off_t i;
for (i = 0; i < size; i++)
{
uint8_t c;
int err = lfs_cache_read(lfs, rcache, pcache, block, off + i, &c, 1);
if (err)
{
return err;
}
lfs_crc(crc, &c, 1);
}
return 0;
}
static inline void lfs_cache_drop(FAR lfs_t *lfs, FAR lfs_cache_t *rcache)
{
/* do not zero, cheaper if cache is readonly or only going to be
* written with identical data (during relocates)
*/
rcache->block = 0xffffffff;
}
static inline void lfs_cache_zero(FAR lfs_t *lfs, FAR lfs_cache_t *pcache)
{
/* zero to avoid information leak */
memset(pcache->buffer, 0xff, lfs->cfg->prog_size);
pcache->block = 0xffffffff;
}
static int lfs_cache_flush(FAR lfs_t *lfs, FAR lfs_cache_t *pcache,
FAR lfs_cache_t *rcache)
{
if (pcache->block != 0xffffffff)
{
int err = lfs->cfg->prog(lfs->cfg, pcache->block, pcache->off,
pcache->buffer, lfs->cfg->prog_size);
if (err)
{
return err;
}
if (rcache)
{
int res = lfs_cache_cmp(lfs, rcache, NULL, pcache->block,
pcache->off, pcache->buffer,
lfs->cfg->prog_size);
if (res < 0)
{
return res;
}
if (!res)
{
return LFS_ERR_CORRUPT;
}
}
lfs_cache_zero(lfs, pcache);
}
return 0;
}
static int lfs_cache_prog(FAR lfs_t *lfs, FAR lfs_cache_t *pcache,
FAR lfs_cache_t *rcache, lfs_block_t block,
lfs_off_t off, FAR const void *buffer,
lfs_size_t size)
{
FAR const uint8_t *data = buffer;
LFS_ASSERT(block < lfs->cfg->block_count);
while (size > 0)
{
if (block == pcache->block && off >= pcache->off &&
off < pcache->off + lfs->cfg->prog_size)
{
/* is already in pcache? */
lfs_size_t diff =
lfs_min(size, lfs->cfg->prog_size - (off - pcache->off));
memcpy(&pcache->buffer[off - pcache->off], data, diff);
data += diff;
off += diff;
size -= diff;
if (off % lfs->cfg->prog_size == 0)
{
/* eagerly flush out pcache if we fill up */
int err = lfs_cache_flush(lfs, pcache, rcache);
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 == 0xffffffff);
if (off % lfs->cfg->prog_size == 0 && size >= lfs->cfg->prog_size)
{
/* bypass pcache? */
lfs_size_t diff = size - (size % lfs->cfg->prog_size);
int err = lfs->cfg->prog(lfs->cfg, block, off, data, diff);
if (err)
{
return err;
}
if (rcache)
{
int res =
lfs_cache_cmp(lfs, rcache, NULL, block, off, data, diff);
if (res < 0)
{
return res;
}
if (!res)
{
return LFS_ERR_CORRUPT;
}
}
data += diff;
off += diff;
size -= diff;
continue;
}
/* prepare pcache, first condition can no longer fail */
pcache->block = block;
pcache->off = off - (off % lfs->cfg->prog_size);
}
return 0;
}
/* General lfs block device operations */
static int lfs_bd_read(FAR lfs_t *lfs, lfs_block_t block, lfs_off_t off,
FAR void *buffer, lfs_size_t size)
{
/* if we ever do more than writes to alternating pairs,
* this may need to consider pcache
*/
return lfs_cache_read(lfs, &lfs->rcache, NULL, block, off, buffer, size);
}
static int lfs_bd_prog(FAR lfs_t *lfs, lfs_block_t block, lfs_off_t off,
FAR const void *buffer, lfs_size_t size)
{
return lfs_cache_prog(lfs, &lfs->pcache, NULL, block, off, buffer, size);
}
static int lfs_bd_cmp(FAR lfs_t *lfs, lfs_block_t block, lfs_off_t off,
FAR const void *buffer, lfs_size_t size)
{
return lfs_cache_cmp(lfs, &lfs->rcache, NULL, block, off, buffer, size);
}
static int lfs_bd_crc(FAR lfs_t *lfs, lfs_block_t block, lfs_off_t off,
lfs_size_t size, FAR uint32_t *crc)
{
return lfs_cache_crc(lfs, &lfs->rcache, NULL, block, off, size, crc);
}
static int lfs_bd_erase(FAR lfs_t *lfs, lfs_block_t block)
{
return lfs->cfg->erase(lfs->cfg, block);
}
static int lfs_bd_sync(FAR lfs_t *lfs)
{
lfs_cache_drop(lfs, &lfs->rcache);
int err = lfs_cache_flush(lfs, &lfs->pcache, NULL);
if (err)
{
return err;
}
return lfs->cfg->sync(lfs->cfg);
}
/* Block allocator */
static int lfs_alloc_lookahead(FAR void *p, lfs_block_t block)
{
FAR lfs_t *lfs = p;
lfs_block_t off =
((block - lfs->free.off) + lfs->cfg->block_count) %
lfs->cfg->block_count;
if (off < lfs->free.size)
{
lfs->free.buffer[off / 32] |= 1U << (off % 32);
}
return 0;
}
static int lfs_alloc(FAR lfs_t *lfs, FAR lfs_block_t *block)
{
while (true)
{
while (lfs->free.i != lfs->free.size)
{
lfs_block_t off = lfs->free.i;
lfs->free.i += 1;
lfs->free.ack -= 1;
if (!(lfs->free.buffer[off / 32] & (1U << (off % 32))))
{
/* found a free block */
*block = (lfs->free.off + off) % lfs->cfg->block_count;
/* eagerly find next off so an alloc ack can
* discredit old lookahead blocks
*/
while (lfs->free.i != lfs->free.size &&
(lfs->free.buffer[lfs->free.i / 32] &
(1U << (lfs->free.i % 32))))
{
lfs->free.i += 1;
lfs->free.ack -= 1;
}
return 0;
}
}
/* check if we have looked at all blocks since last ack */
if (lfs->free.ack == 0)
{
LFS_WARN("No more free space %" PRIu32,
lfs->free.i + lfs->free.off);
return LFS_ERR_NOSPC;
}
lfs->free.off = (lfs->free.off + lfs->free.size) %
lfs->cfg->block_count;
lfs->free.size = lfs_min(lfs->cfg->lookahead, lfs->free.ack);
lfs->free.i = 0;
/* find mask of free blocks from tree */
memset(lfs->free.buffer, 0, lfs->cfg->lookahead / 8);
int err = lfs_traverse(lfs, lfs_alloc_lookahead, lfs);
if (err)
{
return err;
}
}
}
static void lfs_alloc_ack(FAR lfs_t *lfs)
{
lfs->free.ack = lfs->cfg->block_count;
}
/* Endian swapping functions */
static void lfs_dir_fromle32(FAR struct lfs_disk_dir_s *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 lfs_dir_tole32(FAR struct lfs_disk_dir_s *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 lfs_entry_fromle32(FAR struct lfs_disk_entry_s *d)
{
d->u.dir[0] = lfs_fromle32(d->u.dir[0]);
d->u.dir[1] = lfs_fromle32(d->u.dir[1]);
}
static void lfs_entry_tole32(FAR struct lfs_disk_entry_s *d)
{
d->u.dir[0] = lfs_tole32(d->u.dir[0]);
d->u.dir[1] = lfs_tole32(d->u.dir[1]);
}
static void lfs_superblock_fromle32(FAR struct lfs_disk_superblock_s *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);
}
static void lfs_superblock_tole32(FAR struct lfs_disk_superblock_s *d)
{
d->root[0] = lfs_tole32(d->root[0]);
d->root[1] = lfs_tole32(d->root[1]);
d->block_size = lfs_tole32(d->block_size);
d->block_count = lfs_tole32(d->block_count);
d->version = lfs_tole32(d->version);
}
/* Metadata pair and directory operations */
static inline void lfs_pairswap(FAR lfs_block_t pair[2])
{
lfs_block_t t = pair[0];
pair[0] = pair[1];
pair[1] = t;
}
static inline bool lfs_pairisnull(FAR const lfs_block_t pair[2])
{
return pair[0] == 0xffffffff || pair[1] == 0xffffffff;
}
static inline int lfs_paircmp(FAR const lfs_block_t paira[2],
FAR 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_pairsync(FAR const lfs_block_t paira[2],
FAR 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 lfs_size_t lfs_entry_size(FAR const lfs_entry_t *entry)
{
return 4 + entry->d.elen + entry->d.alen + entry->d.nlen;
}
static int lfs_dir_alloc(FAR lfs_t *lfs, FAR lfs_dir_t *dir)
{
int i;
/* allocate pair of dir blocks */
for (i = 0; i < 2; i++)
{
int err = lfs_alloc(lfs, &dir->pair[i]);
if (err)
{
return err;
}
}
/* rather than clobbering one of the blocks we just pretend
* the revision may be valid
*/
int err = lfs_bd_read(lfs, dir->pair[0], 0, &dir->d.rev, 4);
if (err && err != LFS_ERR_CORRUPT)
{
return err;
}
if (err != LFS_ERR_CORRUPT)
{
dir->d.rev = lfs_fromle32(dir->d.rev);
}
/* set defaults */
dir->d.rev += 1;
dir->d.size = sizeof(dir->d) + 4;
dir->d.tail[0] = 0xffffffff;
dir->d.tail[1] = 0xffffffff;
dir->off = sizeof(dir->d);
/* don't write out yet, let caller take care of that */
return 0;
}
static int lfs_dir_fetch(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR const lfs_block_t pair[2])
{
/* copy out pair, otherwise may be aliasing dir */
FAR const lfs_block_t tpair[2] =
{
pair[0], pair[1]
};
bool valid = false;
int i;
/* check both blocks for the most recent revision */
for (i = 0; i < 2; i++)
{
struct lfs_disk_dir_s test;
uint32_t crc;
int err = lfs_bd_read(lfs, tpair[i], 0, &test, sizeof(test));
lfs_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;
}
crc = 0xffffffff;
lfs_dir_tole32(&test);
lfs_crc(&crc, &test, sizeof(test));
lfs_dir_fromle32(&test);
err = lfs_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 %" PRIu32 " %" PRIu32, tpair[0],
tpair[1]);
return LFS_ERR_CORRUPT;
}
return 0;
}
static int lfs_dir_commit(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR const struct lfs_region_s *regions, int count)
{
FAR lfs_dir_t *d;
lfs_block_t oldpair[2];
bool relocated;
int i;
/* increment revision count */
dir->d.rev += 1;
/* keep pairs in order such that pair[0] is most recent */
lfs_pairswap(dir->pair);
for (i = 0; i < count; i++)
{
dir->d.size += regions[i].newlen - regions[i].oldlen;
}
oldpair[0] = dir->pair[0];
oldpair[1] = dir->pair[1];
relocated = false;
while (true)
{
if (true)
{
uint32_t crc;
int err = lfs_bd_erase(lfs, dir->pair[0]);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
crc = 0xffffffff;
lfs_dir_tole32(&dir->d);
lfs_crc(&crc, &dir->d, sizeof(dir->d));
err = lfs_bd_prog(lfs, dir->pair[0], 0, &dir->d, sizeof(dir->d));
lfs_dir_fromle32(&dir->d);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
i = 0;
lfs_off_t oldoff = sizeof(dir->d);
lfs_off_t newoff = sizeof(dir->d);
while (newoff < (0x7fffffff & dir->d.size) - 4)
{
if (i < count && regions[i].oldoff == oldoff)
{
lfs_crc(&crc, regions[i].newdata, regions[i].newlen);
err = lfs_bd_prog(lfs, dir->pair[0], newoff,
regions[i].newdata, regions[i].newlen);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
oldoff += regions[i].oldlen;
newoff += regions[i].newlen;
i += 1;
}
else
{
uint8_t data;
err = lfs_bd_read(lfs, oldpair[1], oldoff, &data, 1);
if (err)
{
return err;
}
lfs_crc(&crc, &data, 1);
err = lfs_bd_prog(lfs, dir->pair[0], newoff, &data, 1);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
oldoff += 1;
newoff += 1;
}
}
crc = lfs_tole32(crc);
err = lfs_bd_prog(lfs, dir->pair[0], newoff, &crc, 4);
crc = lfs_fromle32(crc);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
err = lfs_bd_sync(lfs);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
/* successful commit, check checksum to make sure */
uint32_t ncrc = 0xffffffff;
err = lfs_bd_crc(lfs, dir->pair[0], 0,
(0x7fffffff & dir->d.size) - 4, &ncrc);
if (err)
{
return err;
}
if (ncrc != crc)
{
goto relocate;
}
}
break;
relocate:
/* Commit was corrupted */
LFS_DEBUG("Bad block at %" PRIu32, dir->pair[0]);
/* Drop caches and prepare to relocate block */
relocated = true;
lfs_cache_drop(lfs, &lfs->pcache);
/* Can't relocate superblock, filesystem is now frozen */
if (lfs_paircmp(oldpair, (const lfs_block_t[2]){ 0, 1 }) == 0)
{
LFS_WARN("Superblock %" PRIu32 " has become unwritable",
oldpair[0]);
return LFS_ERR_CORRUPT;
}
/* relocate half of pair */
int err = lfs_alloc(lfs, &dir->pair[0]);
if (err)
{
return err;
}
}
if (relocated)
{
/* update references if we relocated */
LFS_DEBUG("Relocating %" PRIu32 " %" PRIu32 " to %" PRIu32 " %" PRIu32,
oldpair[0], oldpair[1], dir->pair[0], dir->pair[1]);
int err = lfs_relocate(lfs, oldpair, dir->pair);
if (err)
{
return err;
}
}
/* shift over any directories that are affected */
for (d = lfs->dirs; d; d = d->next)
{
if (lfs_paircmp(d->pair, dir->pair) == 0)
{
d->pair[0] = dir->pair[0];
d->pair[1] = dir->pair[1];
}
}
return 0;
}
static int lfs_dir_update(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR lfs_entry_t *entry, FAR const void *data)
{
int err;
lfs_entry_tole32(&entry->d);
err = lfs_dir_commit(
lfs, dir,
(struct lfs_region_s[])
{
{
entry->off, sizeof(entry->d), &entry->d, sizeof(entry->d)
},
{
entry->off + sizeof(entry->d), entry->d.nlen, data, entry->d.nlen
}
},
data ? 2 : 1);
lfs_entry_fromle32(&entry->d);
return err;
}
static int lfs_dir_append(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR lfs_entry_t *entry, FAR const void *data)
{
/* check if we fit, if top bit is set we do not and move on */
while (true)
{
if (dir->d.size + lfs_entry_size(entry) <= lfs->cfg->block_size)
{
entry->off = dir->d.size - 4;
lfs_entry_tole32(&entry->d);
int err =
lfs_dir_commit(lfs, dir,
(struct lfs_region_s[])
{
{
entry->off, 0, &entry->d, sizeof(entry->d)
},
{
entry->off, 0, data, entry->d.nlen
}
},
2);
lfs_entry_fromle32(&entry->d);
return err;
}
/* we need to allocate a new dir block */
if (!(0x80000000 & dir->d.size))
{
lfs_dir_t olddir = *dir;
int err = lfs_dir_alloc(lfs, dir);
if (err)
{
return err;
}
dir->d.tail[0] = olddir.d.tail[0];
dir->d.tail[1] = olddir.d.tail[1];
entry->off = dir->d.size - 4;
lfs_entry_tole32(&entry->d);
err = lfs_dir_commit(lfs, dir,
(struct lfs_region_s[])
{
{
entry->off, 0, &entry->d, sizeof(entry->d)
},
{
entry->off, 0, data, entry->d.nlen
}
},
2);
lfs_entry_fromle32(&entry->d);
if (err)
{
return err;
}
olddir.d.size |= 0x80000000;
olddir.d.tail[0] = dir->pair[0];
olddir.d.tail[1] = dir->pair[1];
return lfs_dir_commit(lfs, &olddir, NULL, 0);
}
int err = lfs_dir_fetch(lfs, dir, dir->d.tail);
if (err)
{
return err;
}
}
}
static int lfs_dir_remove(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR lfs_entry_t *entry)
{
FAR lfs_file_t *f;
FAR lfs_dir_t *d;
int err;
/* check if we should just drop the directory block */
if ((dir->d.size & 0x7fffffff) ==
sizeof(dir->d) + 4 + lfs_entry_size(entry))
{
lfs_dir_t pdir;
int res = lfs_pred(lfs, dir->pair, &pdir);
if (res < 0)
{
return res;
}
if (pdir.d.size & 0x80000000)
{
pdir.d.size &= dir->d.size | 0x7fffffff;
pdir.d.tail[0] = dir->d.tail[0];
pdir.d.tail[1] = dir->d.tail[1];
return lfs_dir_commit(lfs, &pdir, NULL, 0);
}
}
/* shift out the entry */
err = lfs_dir_commit(lfs, dir,
(struct lfs_region_s[])
{
{
entry->off, lfs_entry_size(entry), NULL, 0
},
},
1);
if (err)
{
return err;
}
/* shift over any files/directories that are affected */
for (f = lfs->files; f; f = f->next)
{
if (lfs_paircmp(f->pair, dir->pair) == 0)
{
if (f->poff == entry->off)
{
f->pair[0] = 0xffffffff;
f->pair[1] = 0xffffffff;
}
else if (f->poff > entry->off)
{
f->poff -= lfs_entry_size(entry);
}
}
}
for (d = lfs->dirs; d; d = d->next)
{
if (lfs_paircmp(d->pair, dir->pair) == 0)
{
if (d->off > entry->off)
{
d->off -= lfs_entry_size(entry);
d->pos -= lfs_entry_size(entry);
}
}
}
return 0;
}
static int lfs_dir_next(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR lfs_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 = lfs_dir_fetch(lfs, dir, dir->d.tail);
if (err)
{
return err;
}
dir->off = sizeof(dir->d);
dir->pos += sizeof(dir->d) + 4;
}
int err = lfs_bd_read(lfs, dir->pair[0], dir->off, &entry->d,
sizeof(entry->d));
lfs_entry_fromle32(&entry->d);
if (err)
{
return err;
}
entry->off = dir->off;
dir->off += lfs_entry_size(entry);
dir->pos += lfs_entry_size(entry);
return 0;
}
static int lfs_dir_find(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR lfs_entry_t *entry,
FAR const char **path)
{
FAR const char *pathname = *path;
size_t pathlen;
entry->d.type = LFS_TYPE_DIR;
entry->d.elen = sizeof(entry->d) - 4;
entry->d.alen = 0;
entry->d.nlen = 0;
entry->d.u.dir[0] = lfs->root[0];
entry->d.u.dir[1] = lfs->root[1];
while (true)
{
FAR const char *suffix;
size_t sufflen;
int depth;
nextname:
/* skip slashes */
pathname += strspn(pathname, "/");
pathlen = strcspn(pathname, "/");
/* skip '.' and root '..' */
if ((pathlen == 1 && memcmp(pathname, ".", 1) == 0) ||
(pathlen == 2 && memcmp(pathname, "..", 2) == 0))
{
pathname += pathlen;
goto nextname;
}
/* skip if matched by '..' in name */
suffix = pathname + pathlen;
depth = 1;
while (true)
{
suffix += strspn(suffix, "/");
sufflen = strcspn(suffix, "/");
if (sufflen == 0)
{
break;
}
if (sufflen == 2 && memcmp(suffix, "..", 2) == 0)
{
depth -= 1;
if (depth == 0)
{
pathname = suffix + sufflen;
goto nextname;
}
}
else
{
depth += 1;
}
suffix += sufflen;
}
/* found path */
if (pathname[0] == '\0')
{
return 0;
}
/* update what we've found */
*path = pathname;
/* continue on if we hit a directory */
if (entry->d.type != LFS_TYPE_DIR)
{
return LFS_ERR_NOTDIR;
}
int err = lfs_dir_fetch(lfs, dir, entry->d.u.dir);
if (err)
{
return err;
}
/* find entry matching name */
while (true)
{
err = lfs_dir_next(lfs, dir, entry);
if (err)
{
return err;
}
if (((0x7f & entry->d.type) != LFS_TYPE_REG &&
(0x7f & entry->d.type) != LFS_TYPE_DIR) ||
entry->d.nlen != pathlen)
{
continue;
}
int res = lfs_bd_cmp(lfs, dir->pair[0],
entry->off + 4 + entry->d.elen + entry->d.alen,
pathname, pathlen);
if (res < 0)
{
return res;
}
/* found match */
if (res)
{
break;
}
}
/* check that entry has not been moved */
if (!lfs->moving && entry->d.type & 0x80)
{
int moved = lfs_moved(lfs, &entry->d.u);
if (moved < 0 || moved)
{
return (moved < 0) ? moved : LFS_ERR_NOENT;
}
entry->d.type &= ~0x80;
}
/* to next name */
pathname += pathlen;
}
}
/* File index list operations */
static int lfs_ctz_index(FAR lfs_t *lfs, FAR 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(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR const lfs_cache_t *pcache, lfs_block_t head,
lfs_size_t size, lfs_size_t pos,
FAR lfs_block_t *block, FAR lfs_off_t *off)
{
if (size == 0)
{
*block = 0xffffffff;
*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)
{
int err;
lfs_size_t skip =
lfs_min(lfs_npw2(current - target + 1) - 1, lfs_ctz(current));
err = lfs_cache_read(lfs, rcache, pcache, head, 4 * skip, &head, 4);
head = lfs_fromle32(head);
if (err)
{
return err;
}
LFS_ASSERT(head >= 2 && head <= lfs->cfg->block_count);
current -= 1 << skip;
}
*block = head;
*off = pos;
return 0;
}
static int lfs_ctz_extend(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR lfs_cache_t *pcache, lfs_block_t head,
lfs_size_t size, FAR lfs_block_t *block,
FAR lfs_off_t *off)
{
while (true)
{
lfs_block_t nblock;
int err;
/* go ahead and grab a block */
err = lfs_alloc(lfs, &nblock);
if (err)
{
return err;
}
LFS_ASSERT(nblock >= 2 && nblock <= lfs->cfg->block_count);
if (true)
{
lfs_off_t index;
lfs_size_t skips;
lfs_off_t i;
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;
}
size -= 1;
index = lfs_ctz_index(lfs, &size);
size += 1;
/* just copy out the last block if it is incomplete */
if (size != lfs->cfg->block_size)
{
for (i = 0; i < size; i++)
{
uint8_t data;
err = lfs_cache_read(lfs, rcache, NULL, head, i,
&data, 1);
if (err)
{
return err;
}
err = lfs_cache_prog(lfs, pcache, rcache, nblock, i,
&data, 1);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
}
*block = nblock;
*off = size;
return 0;
}
/* append block */
index += 1;
skips = lfs_ctz(index) + 1;
for (i = 0; i < skips; i++)
{
head = lfs_tole32(head);
err = lfs_cache_prog(lfs, pcache, rcache, nblock, 4 * i,
&head, 4);
head = lfs_fromle32(head);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
if (i != skips - 1)
{
err = lfs_cache_read(lfs, rcache, NULL, head, 4 * i,
&head, 4);
head = lfs_fromle32(head);
if (err)
{
return err;
}
}
LFS_ASSERT(head >= 2 && head <= lfs->cfg->block_count);
}
*block = nblock;
*off = 4 * skips;
return 0;
}
relocate:
LFS_DEBUG("Bad block at %" PRIu32, nblock);
/* just clear cache and try a new block */
lfs_cache_drop(lfs, &lfs->pcache);
}
}
static int lfs_ctz_traverse(FAR lfs_t *lfs, FAR lfs_cache_t *rcache,
FAR const lfs_cache_t *pcache, lfs_block_t head,
FAR lfs_size_t size,
CODE int (*cb)(FAR void *, lfs_block_t),
FAR void *data)
{
lfs_off_t index;
if (size == 0)
{
return 0;
}
index = lfs_ctz_index(lfs, &(lfs_off_t){ size - 1 });
while (true)
{
lfs_block_t heads[2];
int count;
int err;
int i;
err = cb(data, head);
if (err)
{
return err;
}
if (index == 0)
{
return 0;
}
count = 2 - (index & 1);
err = lfs_cache_read(lfs, rcache, pcache, head, 0, &heads, count * 4);
heads[0] = lfs_fromle32(heads[0]);
heads[1] = lfs_fromle32(heads[1]);
if (err)
{
return err;
}
for (i = 0; i < count - 1; i++)
{
err = cb(data, heads[i]);
if (err)
{
return err;
}
}
head = heads[count - 1];
index -= count;
}
}
static int lfs_file_relocate(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
lfs_block_t nblock;
lfs_off_t i;
int err;
relocate:
LFS_DEBUG("Bad block at %" PRIu32, file->block);
/* just relocate what exists into new block */
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 (i = 0; i < file->off; i++)
{
uint8_t data;
err = lfs_cache_read(lfs, &lfs->rcache, &file->cache, file->block, i,
&data, 1);
if (err)
{
return err;
}
err = lfs_cache_prog(lfs, &lfs->pcache, &lfs->rcache, 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->prog_size);
file->cache.block = lfs->pcache.block;
file->cache.off = lfs->pcache.off;
lfs_cache_zero(lfs, &lfs->pcache);
file->block = nblock;
return 0;
}
static int lfs_file_flush(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
if (file->flags & LFS_F_READING)
{
/* just drop read cache */
lfs_cache_drop(lfs, &file->cache);
file->flags &= ~LFS_F_READING;
}
if (file->flags & LFS_F_WRITING)
{
lfs_off_t pos = file->pos;
/* copy over anything after current branch */
lfs_file_t orig =
{
.head = file->head,
.size = file->size,
.flags = LFS_O_RDONLY,
.pos = file->pos,
.cache = lfs->rcache,
};
lfs_cache_drop(lfs, &lfs->rcache);
while (file->pos < file->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_read(lfs, &orig, &data, 1);
if (res < 0)
{
return res;
}
res = lfs_file_write(lfs, file, &data, 1);
if (res < 0)
{
return res;
}
/* keep our reference to the rcache in sync */
if (lfs->rcache.block != 0xffffffff)
{
lfs_cache_drop(lfs, &orig.cache);
lfs_cache_drop(lfs, &lfs->rcache);
}
}
/* write out what we have */
while (true)
{
int err = lfs_cache_flush(lfs, &file->cache, &lfs->rcache);
if (err)
{
if (err == LFS_ERR_CORRUPT)
{
goto relocate;
}
return err;
}
break;
relocate:
err = lfs_file_relocate(lfs, file);
if (err)
{
return err;
}
}
/* actual file updates */
file->head = file->block;
file->size = file->pos;
file->flags &= ~LFS_F_WRITING;
file->flags |= LFS_F_DIRTY;
file->pos = pos;
}
return 0;
}
/* Filesystem operations */
static void lfs_deinit(FAR 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->free.buffer);
}
}
static int lfs_init(FAR lfs_t *lfs, FAR const struct lfs_config_s *cfg)
{
lfs->cfg = cfg;
/* setup read cache */
if (lfs->cfg->read_buffer)
{
lfs->rcache.buffer = lfs->cfg->read_buffer;
}
else
{
lfs->rcache.buffer = lfs_malloc(lfs->cfg->read_size);
if (!lfs->rcache.buffer)
{
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->prog_size);
if (!lfs->pcache.buffer)
{
goto cleanup;
}
}
/* zero to avoid information leaks */
lfs_cache_zero(lfs, &lfs->pcache);
lfs_cache_drop(lfs, &lfs->rcache);
/* setup lookahead, round down to nearest 32-bits */
LFS_ASSERT(lfs->cfg->lookahead % 32 == 0);
LFS_ASSERT(lfs->cfg->lookahead > 0);
if (lfs->cfg->lookahead_buffer)
{
lfs->free.buffer = lfs->cfg->lookahead_buffer;
}
else
{
lfs->free.buffer = lfs_malloc(lfs->cfg->lookahead / 8);
if (!lfs->free.buffer)
{
goto cleanup;
}
}
/* check that program and read sizes are multiples of the block size */
LFS_ASSERT(lfs->cfg->prog_size % lfs->cfg->read_size == 0);
LFS_ASSERT(lfs->cfg->block_size % lfs->cfg->prog_size == 0);
/* check that the block size is large enough to fit ctz pointers */
LFS_ASSERT(4 * lfs_npw2(0xffffffff / (lfs->cfg->block_size - 2 * 4)) <=
lfs->cfg->block_size);
/* setup default state */
lfs->root[0] = 0xffffffff;
lfs->root[1] = 0xffffffff;
lfs->files = NULL;
lfs->dirs = NULL;
lfs->deorphaned = false;
lfs->moving = false;
return 0;
cleanup:
lfs_deinit(lfs);
return LFS_ERR_NOMEM;
}
static int lfs_pred(FAR lfs_t *lfs, FAR const lfs_block_t dir[2],
FAR lfs_dir_t *pdir)
{
int err;
if (lfs_pairisnull(lfs->root))
{
return 0;
}
/* iterate over all directory directory entries */
err = lfs_dir_fetch(lfs, pdir, (FAR const lfs_block_t[2]){ 0, 1 });
if (err)
{
return err;
}
while (!lfs_pairisnull(pdir->d.tail))
{
if (lfs_paircmp(pdir->d.tail, dir) == 0)
{
return true;
}
err = lfs_dir_fetch(lfs, pdir, pdir->d.tail);
if (err)
{
return err;
}
}
return false;
}
static int lfs_parent(FAR lfs_t *lfs, FAR const lfs_block_t dir[2],
FAR lfs_dir_t *parent, FAR lfs_entry_t *entry)
{
if (lfs_pairisnull(lfs->root))
{
return 0;
}
parent->d.tail[0] = 0;
parent->d.tail[1] = 1;
/* iterate over all directory directory entries */
while (!lfs_pairisnull(parent->d.tail))
{
int err = lfs_dir_fetch(lfs, parent, parent->d.tail);
if (err)
{
return err;
}
while (true)
{
err = lfs_dir_next(lfs, parent, entry);
if (err && err != LFS_ERR_NOENT)
{
return err;
}
if (err == LFS_ERR_NOENT)
{
break;
}
if (((0x70 & entry->d.type) == (0x70 & LFS_TYPE_DIR)) &&
lfs_paircmp(entry->d.u.dir, dir) == 0)
{
return true;
}
}
}
return false;
}
static int lfs_moved(FAR lfs_t *lfs, FAR const void *e)
{
lfs_dir_t cwd;
lfs_entry_t entry;
int err;
if (lfs_pairisnull(lfs->root))
{
return 0;
}
/* skip superblock */
err = lfs_dir_fetch(lfs, &cwd, (const lfs_block_t[2]){ 0, 1 });
if (err)
{
return err;
}
/* iterate over all directory directory entries */
while (!lfs_pairisnull(cwd.d.tail))
{
err = lfs_dir_fetch(lfs, &cwd, cwd.d.tail);
if (err)
{
return err;
}
while (true)
{
err = lfs_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;
}
static int lfs_relocate(FAR lfs_t *lfs, FAR const lfs_block_t oldpair[2],
FAR const lfs_block_t newpair[2])
{
lfs_dir_t parent;
lfs_entry_t entry;
int res;
/* find parent */
res = lfs_parent(lfs, oldpair, &parent, &entry);
if (res < 0)
{
return res;
}
if (res)
{
int err;
/* update disk, this creates a desync */
entry.d.u.dir[0] = newpair[0];
entry.d.u.dir[1] = newpair[1];
err = lfs_dir_update(lfs, &parent, &entry, NULL);
if (err)
{
return err;
}
/* update internal root */
if (lfs_paircmp(oldpair, lfs->root) == 0)
{
LFS_DEBUG("Relocating root %" PRIu32 " %" PRIu32, newpair[0],
newpair[1]);
lfs->root[0] = newpair[0];
lfs->root[1] = newpair[1];
}
/* clean up bad block, which should now be a desync */
return lfs_deorphan(lfs);
}
/* find pred */
res = lfs_pred(lfs, oldpair, &parent);
if (res < 0)
{
return res;
}
if (res)
{
/* just replace bad pair, no desync can occur */
parent.d.tail[0] = newpair[0];
parent.d.tail[1] = newpair[1];
return lfs_dir_commit(lfs, &parent, NULL, 0);
}
/* couldn't find dir, must be new */
return 0;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/* Top level directory operations */
int lfs_mkdir(FAR lfs_t *lfs, FAR const char *path)
{
lfs_dir_t cwd;
lfs_dir_t dir;
lfs_entry_t entry;
int err;
/* deorphan if we haven't yet, needed at most once after poweron */
if (!lfs->deorphaned)
{
err = lfs_deorphan(lfs);
if (err)
{
return err;
}
}
/* fetch parent directory */
err = lfs_dir_find(lfs, &cwd, &entry, &path);
if (err != LFS_ERR_NOENT || strchr(path, '/') != NULL)
{
return err ? err : LFS_ERR_EXIST;
}
/* build up new directory */
lfs_alloc_ack(lfs);
err = lfs_dir_alloc(lfs, &dir);
if (err)
{
return err;
}
dir.d.tail[0] = cwd.d.tail[0];
dir.d.tail[1] = cwd.d.tail[1];
err = lfs_dir_commit(lfs, &dir, NULL, 0);
if (err)
{
return err;
}
entry.d.type = LFS_TYPE_DIR;
entry.d.elen = sizeof(entry.d) - 4;
entry.d.alen = 0;
entry.d.nlen = strlen(path);
entry.d.u.dir[0] = dir.pair[0];
entry.d.u.dir[1] = dir.pair[1];
cwd.d.tail[0] = dir.pair[0];
cwd.d.tail[1] = dir.pair[1];
err = lfs_dir_append(lfs, &cwd, &entry, path);
if (err)
{
return err;
}
lfs_alloc_ack(lfs);
return 0;
}
int lfs_dir_open(FAR lfs_t *lfs, FAR lfs_dir_t *dir, FAR const char *path)
{
lfs_entry_t entry;
int err;
dir->pair[0] = lfs->root[0];
dir->pair[1] = lfs->root[1];
err = lfs_dir_find(lfs, dir, &entry, &path);
if (err)
{
return err;
}
else if (entry.d.type != LFS_TYPE_DIR)
{
return LFS_ERR_NOTDIR;
}
err = lfs_dir_fetch(lfs, dir, entry.d.u.dir);
if (err)
{
return err;
}
/* setup head dir
* special offset for '.' and '..'
*/
dir->head[0] = dir->pair[0];
dir->head[1] = dir->pair[1];
dir->pos = sizeof(dir->d) - 2;
dir->off = sizeof(dir->d);
/* add to list of directories */
dir->next = lfs->dirs;
lfs->dirs = dir;
return 0;
}
int lfs_dir_close(FAR lfs_t *lfs, FAR lfs_dir_t *dir)
{
FAR lfs_dir_t **p;
/* remove from list of directories */
for (p = &lfs->dirs; *p; p = &(*p)->next)
{
if (*p == dir)
{
*p = dir->next;
break;
}
}
return 0;
}
int lfs_dir_read(FAR lfs_t *lfs, FAR lfs_dir_t *dir,
FAR struct lfs_info_s *info)
{
lfs_entry_t entry;
memset(info, 0, sizeof(*info));
/* special offset for '.' and '..' */
if (dir->pos == sizeof(dir->d) - 2)
{
info->type = LFS_TYPE_DIR;
strcpy(info->name, ".");
dir->pos += 1;
return 1;
}
else if (dir->pos == sizeof(dir->d) - 1)
{
info->type = LFS_TYPE_DIR;
strcpy(info->name, "..");
dir->pos += 1;
return 1;
}
while (true)
{
int err = lfs_dir_next(lfs, dir, &entry);
if (err)
{
return (err == LFS_ERR_NOENT) ? 0 : err;
}
if ((0x7f & entry.d.type) != LFS_TYPE_REG &&
(0x7f & entry.d.type) != LFS_TYPE_DIR)
{
continue;
}
/* check that entry has not been moved */
if (entry.d.type & 0x80)
{
int moved = lfs_moved(lfs, &entry.d.u);
if (moved < 0)
{
return moved;
}
if (moved)
{
continue;
}
entry.d.type &= ~0x80;
}
break;
}
info->type = entry.d.type;
if (info->type == LFS_TYPE_REG)
{
info->size = entry.d.u.file.size;
}
int err = lfs_bd_read(lfs, dir->pair[0],
entry.off + 4 + entry.d.elen + entry.d.alen,
info->name, entry.d.nlen);
if (err)
{
return err;
}
return 1;
}
int lfs_dir_seek(FAR lfs_t *lfs, FAR lfs_dir_t *dir, lfs_off_t off)
{
int err;
/* simply walk from head dir */
err = lfs_dir_rewind(lfs, dir);
if (err)
{
return err;
}
dir->pos = off;
while (off > (0x7fffffff & dir->d.size))
{
off -= 0x7fffffff & dir->d.size;
if (!(0x80000000 & dir->d.size))
{
return LFS_ERR_INVAL;
}
err = lfs_dir_fetch(lfs, dir, dir->d.tail);
if (err)
{
return err;
}
}
dir->off = off;
return 0;
}
lfs_soff_t lfs_dir_tell(FAR lfs_t *lfs, FAR lfs_dir_t *dir)
{
return dir->pos;
}
int lfs_dir_rewind(FAR lfs_t *lfs, FAR lfs_dir_t *dir)
{
int err;
/* reload the head dir */
err = lfs_dir_fetch(lfs, dir, dir->head);
if (err)
{
return err;
}
dir->pair[0] = dir->head[0];
dir->pair[1] = dir->head[1];
dir->pos = sizeof(dir->d) - 2;
dir->off = sizeof(dir->d);
return 0;
}
/* Top level file operations */
int lfs_file_opencfg(FAR lfs_t *lfs, FAR lfs_file_t *file,
FAR const char *path, int flags,
FAR const struct lfs_file_config_s *cfg)
{
lfs_dir_t cwd;
lfs_entry_t entry;
int err;
/* deorphan if we haven't yet, needed at most once after poweron */
if ((flags & 3) != LFS_O_RDONLY && !lfs->deorphaned)
{
err = lfs_deorphan(lfs);
if (err)
{
return err;
}
}
/* allocate entry for file if it doesn't exist */
err = lfs_dir_find(lfs, &cwd, &entry, &path);
if (err && (err != LFS_ERR_NOENT || strchr(path, '/') != NULL))
{
return err;
}
if (err == LFS_ERR_NOENT)
{
if (!(flags & LFS_O_CREAT))
{
return LFS_ERR_NOENT;
}
/* create entry to remember name */
entry.d.type = LFS_TYPE_REG;
entry.d.elen = sizeof(entry.d) - 4;
entry.d.alen = 0;
entry.d.nlen = strlen(path);
entry.d.u.file.head = 0xffffffff;
entry.d.u.file.size = 0;
err = lfs_dir_append(lfs, &cwd, &entry, path);
if (err)
{
return err;
}
}
else if (entry.d.type == LFS_TYPE_DIR)
{
return LFS_ERR_ISDIR;
}
else if (flags & LFS_O_EXCL)
{
return LFS_ERR_EXIST;
}
/* setup file struct */
file->cfg = cfg;
file->pair[0] = cwd.pair[0];
file->pair[1] = cwd.pair[1];
file->poff = entry.off;
file->head = entry.d.u.file.head;
file->size = entry.d.u.file.size;
file->flags = flags;
file->pos = 0;
if (flags & LFS_O_TRUNC)
{
if (file->size != 0)
{
file->flags |= LFS_F_DIRTY;
}
file->head = 0xffffffff;
file->size = 0;
}
/* allocate buffer if needed */
file->cache.block = 0xffffffff;
if (file->cfg && file->cfg->buffer)
{
file->cache.buffer = file->cfg->buffer;
}
else if (lfs->cfg->file_buffer)
{
if (lfs->files)
{
/* already in use */
return LFS_ERR_NOMEM;
}
file->cache.buffer = lfs->cfg->file_buffer;
}
else if ((file->flags & 3) == LFS_O_RDONLY)
{
file->cache.buffer = lfs_malloc(lfs->cfg->read_size);
if (!file->cache.buffer)
{
return LFS_ERR_NOMEM;
}
}
else
{
file->cache.buffer = lfs_malloc(lfs->cfg->prog_size);
if (!file->cache.buffer)
{
return LFS_ERR_NOMEM;
}
}
/* zero to avoid information leak */
lfs_cache_drop(lfs, &file->cache);
if ((file->flags & 3) != LFS_O_RDONLY)
{
lfs_cache_zero(lfs, &file->cache);
}
/* add to list of files */
file->next = lfs->files;
lfs->files = file;
return 0;
}
int lfs_file_open(FAR lfs_t *lfs, FAR lfs_file_t *file,
FAR const char *path, int flags)
{
return lfs_file_opencfg(lfs, file, path, flags, NULL);
}
int lfs_file_close(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
FAR lfs_file_t **p;
int err;
err = lfs_file_sync(lfs, file);
/* remove from list of files */
for (p = &lfs->files; *p; p = &(*p)->next)
{
if (*p == file)
{
*p = file->next;
break;
}
}
/* clean up memory */
if (!(file->cfg && file->cfg->buffer) && !lfs->cfg->file_buffer)
{
lfs_free(file->cache.buffer);
}
return err;
}
int lfs_file_sync(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
int err = lfs_file_flush(lfs, file);
if (err)
{
return err;
}
if ((file->flags & LFS_F_DIRTY) && !(file->flags & LFS_F_ERRED) &&
!lfs_pairisnull(file->pair))
{
lfs_dir_t cwd;
lfs_entry_t entry =
{
.off = file->poff
};
/* update dir entry */
err = lfs_dir_fetch(lfs, &cwd, file->pair);
if (err)
{
return err;
}
err = lfs_bd_read(lfs, cwd.pair[0], entry.off, &entry.d,
sizeof(entry.d));
lfs_entry_fromle32(&entry.d);
if (err)
{
return err;
}
LFS_ASSERT(entry.d.type == LFS_TYPE_REG);
entry.d.u.file.head = file->head;
entry.d.u.file.size = file->size;
err = lfs_dir_update(lfs, &cwd, &entry, NULL);
if (err)
{
return err;
}
file->flags &= ~LFS_F_DIRTY;
}
return 0;
}
lfs_ssize_t lfs_file_read(FAR lfs_t *lfs, FAR lfs_file_t *file,
FAR void *buffer, lfs_size_t size)
{
FAR uint8_t *data = buffer;
lfs_size_t nsize = size;
if ((file->flags & 3) == LFS_O_WRONLY)
{
return LFS_ERR_BADF;
}
if (file->flags & LFS_F_WRITING)
{
/* flush out any writes */
int err = lfs_file_flush(lfs, file);
if (err)
{
return err;
}
}
if (file->pos >= file->size)
{
/* eof if past end */
return 0;
}
size = lfs_min(size, file->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)
{
int err =
lfs_ctz_find(lfs, &file->cache, NULL, file->head, file->size,
file->pos, &file->block, &file->off);
if (err)
{
return err;
}
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);
int err = lfs_cache_read(lfs, &file->cache, NULL, file->block,
file->off, data, diff);
if (err)
{
return err;
}
file->pos += diff;
file->off += diff;
data += diff;
nsize -= diff;
}
return size;
}
lfs_ssize_t lfs_file_write(FAR lfs_t *lfs, FAR lfs_file_t *file,
FAR const void *buffer, lfs_size_t size)
{
FAR const uint8_t *data = buffer;
lfs_size_t nsize = size;
if ((file->flags & 3) == LFS_O_RDONLY)
{
return LFS_ERR_BADF;
}
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->size)
{
file->pos = file->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->size)
{
/* fill with zeros */
lfs_off_t pos = file->pos;
file->pos = file->size;
while (file->pos < pos)
{
lfs_ssize_t res = lfs_file_write(lfs, file, &(uint8_t){ 0 }, 1);
if (res < 0)
{
return res;
}
}
}
while (nsize > 0)
{
lfs_size_t diff;
/* check if we need a new block */
if (!(file->flags & LFS_F_WRITING) || file->off == lfs->cfg->block_size)
{
int err;
if (!(file->flags & LFS_F_WRITING) && file->pos > 0)
{
/* find out which block we're extending from */
err = lfs_ctz_find(lfs, &file->cache, NULL, file->head,
file->size, file->pos - 1, &file->block,
&file->off);
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_ack(lfs);
err = lfs_ctz_extend(lfs, &lfs->rcache, &file->cache, file->block,
file->pos, &file->block, &file->off);
if (err)
{
file->flags |= LFS_F_ERRED;
return err;
}
file->flags |= LFS_F_WRITING;
}
/* program as much as we can in current block */
diff = lfs_min(nsize, lfs->cfg->block_size - file->off);
while (true)
{
int err = lfs_cache_prog(lfs, &file->cache, &lfs->rcache,
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_ack(lfs);
}
file->flags &= ~LFS_F_ERRED;
return size;
}
lfs_soff_t lfs_file_seek(FAR lfs_t *lfs, FAR lfs_file_t *file,
lfs_soff_t off, int whence)
{
lfs_soff_t npos;
int err;
/* write out everything beforehand, may be noop if rdonly */
err = lfs_file_flush(lfs, file);
if (err)
{
return err;
}
/* find new pos */
npos = file->pos;
if (whence == LFS_SEEK_SET)
{
npos = off;
}
else if (whence == LFS_SEEK_CUR)
{
npos = file->pos + off;
}
else if (whence == LFS_SEEK_END)
{
npos = file->size + off;
}
if (npos < 0 || npos > LFS_FILE_MAX)
{
/* file position out of range */
return LFS_ERR_INVAL;
}
/* update pos */
file->pos = npos;
return npos;
}
int lfs_file_truncate(FAR lfs_t *lfs, FAR lfs_file_t *file, lfs_off_t size)
{
lfs_off_t oldsize;
if ((file->flags & 3) == LFS_O_RDONLY)
{
return LFS_ERR_BADF;
}
oldsize = lfs_file_size(lfs, file);
if (size < oldsize)
{
/* 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, &file->cache, NULL, file->head, file->size,
size, &file->head, &(lfs_off_t){ 0 });
if (err)
{
return err;
}
file->size = size;
file->flags |= LFS_F_DIRTY;
}
else if (size > oldsize)
{
int err;
lfs_off_t pos = file->pos;
/* flush+seek if not already at end */
if (file->pos != oldsize)
{
err = lfs_file_seek(lfs, file, 0, LFS_SEEK_END);
if (err < 0)
{
return err;
}
}
/* fill with zeros */
while (file->pos < size)
{
lfs_ssize_t res = lfs_file_write(lfs, file, &(uint8_t){ 0 }, 1);
if (res < 0)
{
return res;
}
}
/* restore pos */
err = lfs_file_seek(lfs, file, pos, LFS_SEEK_SET);
if (err < 0)
{
return err;
}
}
return 0;
}
lfs_soff_t lfs_file_tell(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
return file->pos;
}
int lfs_file_rewind(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
lfs_soff_t res = lfs_file_seek(lfs, file, 0, LFS_SEEK_SET);
if (res < 0)
{
return res;
}
return 0;
}
lfs_soff_t lfs_file_size(FAR lfs_t *lfs, FAR lfs_file_t *file)
{
if (file->flags & LFS_F_WRITING)
{
return lfs_max(file->pos, file->size);
}
else
{
return file->size;
}
}
/* General fs operations */
int lfs_stat(FAR lfs_t *lfs, FAR const char *path,
FAR struct lfs_info_s *info)
{
lfs_dir_t cwd;
lfs_entry_t entry;
int err = lfs_dir_find(lfs, &cwd, &entry, &path);
if (err)
{
return err;
}
memset(info, 0, sizeof(*info));
info->type = entry.d.type;
if (info->type == LFS_TYPE_REG)
{
info->size = entry.d.u.file.size;
}
if (lfs_paircmp(entry.d.u.dir, lfs->root) == 0)
{
strcpy(info->name, "/");
}
else
{
err = lfs_bd_read(lfs, cwd.pair[0],
entry.off + 4 + entry.d.elen + entry.d.alen,
info->name, entry.d.nlen);
if (err)
{
return err;
}
}
return 0;
}
int lfs_remove(FAR lfs_t *lfs, FAR const char *path)
{
lfs_dir_t cwd;
lfs_entry_t entry;
int err;
/* deorphan if we haven't yet, needed at most once after poweron */
if (!lfs->deorphaned)
{
err = lfs_deorphan(lfs);
if (err)
{
return err;
}
}
err = lfs_dir_find(lfs, &cwd, &entry, &path);
if (err)
{
return err;
}
lfs_dir_t dir;
if (entry.d.type == LFS_TYPE_DIR)
{
/* must be empty before removal, checking size
* without masking top bit checks for any case where
* dir is not empty
*/
err = lfs_dir_fetch(lfs, &dir, entry.d.u.dir);
if (err)
{
return err;
}
else if (dir.d.size != sizeof(dir.d) + 4)
{
return LFS_ERR_NOTEMPTY;
}
}
/* remove the entry */
err = lfs_dir_remove(lfs, &cwd, &entry);
if (err)
{
return err;
}
/* if we were a directory, find pred, replace tail */
if (entry.d.type == LFS_TYPE_DIR)
{
int res = lfs_pred(lfs, dir.pair, &cwd);
if (res < 0)
{
return res;
}
LFS_ASSERT(res); /* must have pred */
cwd.d.tail[0] = dir.d.tail[0];
cwd.d.tail[1] = dir.d.tail[1];
err = lfs_dir_commit(lfs, &cwd, NULL, 0);
if (err)
{
return err;
}
}
return 0;
}
int lfs_rename(FAR lfs_t *lfs, FAR const char *oldpath,
FAR const char *newpath)
{
lfs_dir_t oldcwd;
lfs_dir_t newcwd;
lfs_dir_t dir;
lfs_entry_t oldentry;
lfs_entry_t preventry;
lfs_entry_t newentry;
bool prevexists;
int err;
/* deorphan if we haven't yet, needed at most once after poweron */
if (!lfs->deorphaned)
{
err = lfs_deorphan(lfs);
if (err)
{
return err;
}
}
/* find old entry */
err = lfs_dir_find(lfs, &oldcwd, &oldentry,
&(FAR const char *){ oldpath });
if (err)
{
return err;
}
/* mark as moving */
oldentry.d.type |= 0x80;
err = lfs_dir_update(lfs, &oldcwd, &oldentry, NULL);
if (err)
{
return err;
}
/* allocate new entry */
err = lfs_dir_find(lfs, &newcwd, &preventry, &newpath);
if (err && (err != LFS_ERR_NOENT || strchr(newpath, '/') != NULL))
{
return err;
}
/* must have same type */
prevexists = (err != LFS_ERR_NOENT);
if (prevexists && preventry.d.type != (0x7f & oldentry.d.type))
{
return LFS_ERR_ISDIR;
}
if (prevexists && preventry.d.type == LFS_TYPE_DIR)
{
/* must be empty before removal, checking size
* without masking top bit checks for any case where
* dir is not empty
*/
err = lfs_dir_fetch(lfs, &dir, preventry.d.u.dir);
if (err)
{
return err;
}
else if (dir.d.size != sizeof(dir.d) + 4)
{
return LFS_ERR_NOTEMPTY;
}
}
/* move to new location */
newentry = preventry;
newentry.d = oldentry.d;
newentry.d.type &= ~0x80;
newentry.d.nlen = strlen(newpath);
if (prevexists)
{
err = lfs_dir_update(lfs, &newcwd, &newentry, newpath);
if (err)
{
return err;
}
}
else
{
err = lfs_dir_append(lfs, &newcwd, &newentry, newpath);
if (err)
{
return err;
}
}
/* fetch old pair again in case dir block changed */
lfs->moving = true;
err = lfs_dir_find(lfs, &oldcwd, &oldentry, &oldpath);
if (err)
{
return err;
}
lfs->moving = false;
/* remove old entry */
err = lfs_dir_remove(lfs, &oldcwd, &oldentry);
if (err)
{
return err;
}
/* if we were a directory, find pred, replace tail */
if (prevexists && preventry.d.type == LFS_TYPE_DIR)
{
int res = lfs_pred(lfs, dir.pair, &newcwd);
if (res < 0)
{
return res;
}
LFS_ASSERT(res); /* must have pred */
newcwd.d.tail[0] = dir.d.tail[0];
newcwd.d.tail[1] = dir.d.tail[1];
err = lfs_dir_commit(lfs, &newcwd, NULL, 0);
if (err)
{
return err;
}
}
return 0;
}
int lfs_format(FAR lfs_t *lfs, FAR const struct lfs_config_s *cfg)
{
lfs_superblock_t superblock;
bool valid;
int err = 0;
if (true)
{
lfs_dir_t superdir;
lfs_dir_t root;
int i;
err = lfs_init(lfs, cfg);
if (err)
{
return err;
}
/* create free lookahead */
memset(lfs->free.buffer, 0, lfs->cfg->lookahead / 8);
lfs->free.off = 0;
lfs->free.size = lfs_min(lfs->cfg->lookahead, lfs->cfg->block_count);
lfs->free.i = 0;
lfs_alloc_ack(lfs);
/* create superblock dir */
err = lfs_dir_alloc(lfs, &superdir);
if (err)
{
goto cleanup;
}
/* write root directory */
err = lfs_dir_alloc(lfs, &root);
if (err)
{
goto cleanup;
}
err = lfs_dir_commit(lfs, &root, NULL, 0);
if (err)
{
goto cleanup;
}
lfs->root[0] = root.pair[0];
lfs->root[1] = root.pair[1];
/* write superblocks */
superblock.off = sizeof(superdir.d);
superblock.d.type = LFS_TYPE_SUPERBLOCK;
superblock.d.elen = sizeof(superblock.d) -
sizeof(superblock.d.magic) - 4;
superblock.d.nlen = sizeof(superblock.d.magic);
superblock.d.version = LFS_DISK_VERSION;
superblock.d.block_size = lfs->cfg->block_size;
superblock.d.block_count = lfs->cfg->block_count;
superblock.d.root[0] = lfs->root[0];
superblock.d.root[1] = lfs->root[1];
memcpy(superblock.d.magic, "littlefs", 8);
superdir.d.tail[0] = root.pair[0];
superdir.d.tail[1] = root.pair[1];
superdir.d.size = sizeof(superdir.d) +
sizeof(superblock.d) + 4;
/* write both pairs to be safe */
lfs_superblock_tole32(&superblock.d);
valid = false;
for (i = 0; i < 2; i++)
{
err = lfs_dir_commit(
lfs, &superdir,
(struct lfs_region_s[])
{
{
sizeof(superdir.d), sizeof(superblock.d),
&superblock.d, sizeof(superblock.d)
}
},
1);
if (err && err != LFS_ERR_CORRUPT)
{
goto cleanup;
}
valid = valid || !err;
}
if (!valid)
{
err = LFS_ERR_CORRUPT;
goto cleanup;
}
/* sanity check that fetch works */
err = lfs_dir_fetch(lfs, &superdir,
(FAR const lfs_block_t[2]){0, 1});
if (err)
{
goto cleanup;
}
lfs_alloc_ack(lfs);
}
cleanup:
lfs_deinit(lfs);
return err;
}
int lfs_mount(FAR lfs_t *lfs, FAR const struct lfs_config_s *cfg)
{
int err = 0;
if (true)
{
lfs_dir_t dir;
lfs_superblock_t superblock;
uint16_t major_version;
uint16_t minor_version;
err = lfs_init(lfs, cfg);
if (err)
{
return err;
}
/* setup free lookahead */
lfs->free.off = 0;
lfs->free.size = 0;
lfs->free.i = 0;
lfs_alloc_ack(lfs);
/* load superblock */
err = lfs_dir_fetch(lfs, &dir, (const lfs_block_t[2]){0, 1});
if (err && err != LFS_ERR_CORRUPT)
{
goto cleanup;
}
if (!err)
{
err = lfs_bd_read(lfs, dir.pair[0], sizeof(dir.d), &superblock.d,
sizeof(superblock.d));
lfs_superblock_fromle32(&superblock.d);
if (err)
{
goto cleanup;
}
lfs->root[0] = superblock.d.root[0];
lfs->root[1] = superblock.d.root[1];
}
if (err || memcmp(superblock.d.magic, "littlefs", 8) != 0)
{
LFS_ERROR("Invalid superblock at %d %d", 0, 1);
err = LFS_ERR_CORRUPT;
goto cleanup;
}
major_version = (0xffff & (superblock.d.version >> 16));
minor_version = (0xffff & (superblock.d.version >> 0));
if ((major_version != LFS_DISK_VERSION_MAJOR ||
minor_version > LFS_DISK_VERSION_MINOR))
{
LFS_ERROR("Invalid version %d.%d", major_version, minor_version);
err = LFS_ERR_INVAL;
goto cleanup;
}
return 0;
}
cleanup:
lfs_deinit(lfs);
return err;
}
int lfs_unmount(FAR lfs_t *lfs)
{
lfs_deinit(lfs);
return 0;
}
/* Littlefs specific operations */
int lfs_traverse(FAR lfs_t *lfs, CODE int (*cb)(void *, lfs_block_t),
FAR void *data)
{
lfs_dir_t dir;
lfs_entry_t entry;
lfs_block_t cwd[2] =
{
0, 1
};
FAR lfs_file_t *f;
if (lfs_pairisnull(lfs->root))
{
return 0;
}
/* iterate over metadata pairs */
while (true)
{
int err;
int i;
for (i = 0; i < 2; i++)
{
err = cb(data, cwd[i]);
if (err)
{
return err;
}
}
err = lfs_dir_fetch(lfs, &dir, cwd);
if (err)
{
return err;
}
/* iterate over contents */
while (dir.off + sizeof(entry.d) <= (0x7fffffff & dir.d.size) - 4)
{
err = lfs_bd_read(lfs, dir.pair[0], dir.off, &entry.d,
sizeof(entry.d));
lfs_entry_fromle32(&entry.d);
if (err)
{
return err;
}
dir.off += lfs_entry_size(&entry);
if ((0x70 & entry.d.type) == (0x70 & LFS_TYPE_REG))
{
err = lfs_ctz_traverse(lfs, &lfs->rcache, NULL,
entry.d.u.file.head,
entry.d.u.file.size, cb, data);
if (err)
{
return err;
}
}
}
cwd[0] = dir.d.tail[0];
cwd[1] = dir.d.tail[1];
if (lfs_pairisnull(cwd))
{
break;
}
}
/* iterate over any open files */
for (f = lfs->files; f; f = f->next)
{
if (f->flags & LFS_F_DIRTY)
{
int err = lfs_ctz_traverse(lfs, &lfs->rcache, &f->cache, f->head,
f->size, cb, data);
if (err)
{
return err;
}
}
if (f->flags & LFS_F_WRITING)
{
int err = lfs_ctz_traverse(lfs, &lfs->rcache, &f->cache, f->block,
f->pos, cb, data);
if (err)
{
return err;
}
}
}
return 0;
}
int lfs_deorphan(FAR lfs_t *lfs)
{
lfs_dir_t pdir =
{
.d.size = 0x80000000
};
lfs_dir_t cwd =
{
.d.tail[0] = 0,
.d.tail[1] = 1
};
lfs_size_t i;
int err;
lfs->deorphaned = true;
if (lfs_pairisnull(lfs->root))
{
return 0;
}
/* iterate over all directory directory entries */
for (i = 0; i < lfs->cfg->block_count; i++)
{
lfs_entry_t entry;
if (lfs_pairisnull(cwd.d.tail))
{
return 0;
}
err = lfs_dir_fetch(lfs, &cwd, cwd.d.tail);
if (err)
{
return err;
}
/* check head blocks for orphans */
if (!(0x80000000 & pdir.d.size))
{
lfs_dir_t parent;
int res;
/* check if we have a parent */
res = lfs_parent(lfs, pdir.d.tail, &parent, &entry);
if (res < 0)
{
return res;
}
if (!res)
{
/* we are an orphan */
LFS_DEBUG("Found orphan %" PRIu32 " %" PRIu32, pdir.d.tail[0],
pdir.d.tail[1]);
pdir.d.tail[0] = cwd.d.tail[0];
pdir.d.tail[1] = cwd.d.tail[1];
err = lfs_dir_commit(lfs, &pdir, NULL, 0);
if (err)
{
return err;
}
return 0;
}
if (!lfs_pairsync(entry.d.u.dir, pdir.d.tail))
{
/* we have desynced */
LFS_DEBUG("Found desync %" PRIu32 " %" PRIu32, entry.d.u.dir[0],
entry.d.u.dir[1]);
pdir.d.tail[0] = entry.d.u.dir[0];
pdir.d.tail[1] = entry.d.u.dir[1];
err = lfs_dir_commit(lfs, &pdir, NULL, 0);
if (err)
{
return err;
}
return 0;
}
}
/* check entries for moves */
while (true)
{
err = lfs_dir_next(lfs, &cwd, &entry);
if (err && err != LFS_ERR_NOENT)
{
return err;
}
if (err == LFS_ERR_NOENT)
{
break;
}
/* found moved entry */
if (entry.d.type & 0x80)
{
int moved = lfs_moved(lfs, &entry.d.u);
if (moved < 0)
{
return moved;
}
if (moved)
{
LFS_DEBUG("Found move %" PRIu32 " %" PRIu32,
entry.d.u.dir[0], entry.d.u.dir[1]);
err = lfs_dir_remove(lfs, &cwd, &entry);
if (err)
{
return err;
}
}
else
{
LFS_DEBUG("Found partial move %" PRIu32 " %" PRIu32,
entry.d.u.dir[0], entry.d.u.dir[1]);
entry.d.type &= ~0x80;
err = lfs_dir_update(lfs, &cwd, &entry, NULL);
if (err)
{
return err;
}
}
}
}
memcpy(&pdir, &cwd, sizeof(pdir));
}
/* If we reached here, we have more directory pairs than blocks in the
* filesystem... So something must be horribly wrong
*/
return LFS_ERR_CORRUPT;
}