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Added some tests, quick seek impl, fixed bugs

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Turns out it's hard to test file holes without seek.

It's interesting to note most of seek's buffer flush work actually
occurs lazily in lfsr_file_write, so lfsr_file_seek turns out to be a
relatively simple function.
This commit is contained in:
Christopher Haster
2023-09-25 11:58:27 -05:00
parent 0724b9a8c4
commit 582dc5f1b2
3 changed files with 597 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lfs.c
+44 -17
View File
@@ -8487,18 +8487,13 @@ static int lfsr_file_flushbuffer(lfs_t *lfs, lfsr_file_t *file) {
// remove any data we're overwriting, note we need to account for
// left_sibling changes
*attrs_++ = LFSR_ATTR(
lfs_min32(
file->buffer_pos + file->buffer_size
+ right_weight - left_overlap,
file->inlined.u.rbyd.weight)-1,
RM,
-(lfs_min32(
file->buffer_pos + file->buffer_size
+ right_weight - left_overlap,
file->inlined.u.rbyd.weight)
- file->buffer_pos),
NULL);
lfs_off_t rm_size = lfs_min32(
file->buffer_pos + file->buffer_size
+ right_weight - left_overlap,
file->inlined.u.rbyd.weight - left_overlap)
- file->buffer_pos;
*attrs_++ = LFSR_ATTR(file->buffer_pos + rm_size - 1,
RM, -rm_size, NULL);
if (lfsr_data_size(&right_data) == 0) {
// append our buffer with any remaining weight
@@ -8591,11 +8586,6 @@ failed:;
return err;
}
int lfsr_file_flush(lfs_t *lfs, lfsr_file_t *file) {
// TODO
return 0;
}
int lfsr_file_sync(lfs_t *lfs, lfsr_file_t *file) {
if (lfsr_file_iserrored(file->flags)) {
// it's not safe to do anything if our file errored
@@ -8682,6 +8672,43 @@ failed:;
return err;
}
lfs_soff_t lfsr_file_seek(lfs_t *lfs, lfsr_file_t *file,
lfs_soff_t off, uint8_t whence) {
// TODO check for out-of-range?
// figure out our new file position
lfs_off_t pos_;
if (whence == LFS_SEEK_SET) {
pos_ = off;
} else if (whence == LFS_SEEK_CUR) {
pos_ = file->pos + off;
} else if (whence == LFS_SEEK_END) {
pos_ = file->size + off;
} else {
LFS_UNREACHABLE();
}
// out of range?
if (pos_ > lfs->size_limit) {
return LFS_ERR_INVAL;
}
// update file position
file->pos = pos_;
return pos_;
}
lfs_soff_t lfsr_file_tell(lfs_t *lfs, lfsr_file_t *file) {
(void)lfs;
return file->pos;
}
lfs_soff_t lfsr_file_rewind(lfs_t *lfs, lfsr_file_t *file) {
(void)lfs;
file->pos = 0;
return 0;
}
lfs_soff_t lfsr_file_size(lfs_t *lfs, lfsr_file_t *file) {
(void)lfs;
return file->size;
lfs.h
+4
View File
@@ -781,6 +781,8 @@ lfs_ssize_t lfsr_file_write(lfs_t *lfs, lfsr_file_t *file,
// Returns the new position of the file, or a negative error code on failure.
lfs_soff_t lfs_file_seek(lfs_t *lfs, lfs_file_t *file,
lfs_soff_t off, int whence);
lfs_soff_t lfsr_file_seek(lfs_t *lfs, lfsr_file_t *file,
lfs_soff_t off, uint8_t whence);
#ifndef LFS_READONLY
// Truncates the size of the file to the specified size
@@ -794,12 +796,14 @@ int lfs_file_truncate(lfs_t *lfs, lfs_file_t *file, lfs_off_t size);
// Equivalent to lfs_file_seek(lfs, file, 0, LFS_SEEK_CUR)
// Returns the position of the file, or a negative error code on failure.
lfs_soff_t lfs_file_tell(lfs_t *lfs, lfs_file_t *file);
lfs_soff_t lfsr_file_tell(lfs_t *lfs, lfsr_file_t *file);
// Change the position of the file to the beginning of the file
//
// Equivalent to lfs_file_seek(lfs, file, 0, LFS_SEEK_SET)
// Returns a negative error code on failure.
int lfs_file_rewind(lfs_t *lfs, lfs_file_t *file);
int lfsr_file_rewind(lfs_t *lfs, lfsr_file_t *file);
// Return the size of the file
//
tests/test_ftree.toml
+549 -2
View File
@@ -510,7 +510,7 @@ code = '''
# write files incrementally
[cases.test_ftree_incr]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = [4, 1]
defines.CHUNK = ['CACHE_SIZE/2', '4', '1']
defines.SYNC = [false, true]
defines.REMOUNT = [false, true]
reentrant = true
@@ -547,7 +547,7 @@ code = '''
lfsr_mount(&lfs, CFG) => 0;
// note the switch to append here
lfsr_file_open(&lfs, &file, "hello",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
LFS_O_WRONLY | LFS_O_APPEND) => 0;
}
}
lfsr_file_close(&lfs, &file) => 0;
@@ -595,6 +595,553 @@ code = '''
lfsr_unmount(&lfs) => 0;
'''
# overwrite files
[cases.test_ftree_overwrite]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = ['CACHE_SIZE/2', '4', '1']
# bit 0 => first chunk
# bit 1 => middle chunk
# bit 2 => last chunk
defines.MASK = [0, 1, 2, 3, 4, 5, 6, 7]
# 0 => in-order
# 1 => reversed
defines.ORDER = [0, 1]
defines.SYNC = [false, true]
defines.REMOUNT = [false, true]
reentrant = true
code = '''
// format once per test
lfs_t lfs;
int err = lfsr_mount(&lfs, CFG);
if (err) {
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// create a file, truncating in case of powerloss
lfsr_file_t file;
lfsr_file_open(&lfs, &file, "hello",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => 0;
// simulate our file in ram
uint8_t sim[8192];
uint32_t prng = 42;
for (lfs_size_t i = 0; i < SIZE; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_write(&lfs, &file, sim, SIZE) => SIZE;
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write first chunk?
if (MASK & 1) {
if (ORDER == 0) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, 0, LFS_SEEK_SET) => 0;
lfsr_file_write(&lfs, &file, &sim[0], CHUNK) => CHUNK;
} else {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE-CHUNK+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-CHUNK, LFS_SEEK_SET) => SIZE-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-CHUNK], CHUNK) => CHUNK;
}
}
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write second chunk?
if (MASK & 2) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE/2-CHUNK/2+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE/2 - CHUNK/2, LFS_SEEK_SET)
=> SIZE/2 - CHUNK/2;
lfsr_file_write(&lfs, &file, &sim[SIZE/2-CHUNK/2], CHUNK) => CHUNK;
}
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write third chunk?
if (MASK & 4) {
if (ORDER == 0) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE-CHUNK+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-CHUNK, LFS_SEEK_SET) => SIZE-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-CHUNK], CHUNK) => CHUNK;
} else {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, 0, LFS_SEEK_SET) => 0;
lfsr_file_write(&lfs, &file, &sim[0], CHUNK) => CHUNK;
}
}
lfsr_file_close(&lfs, &file) => 0;
// remount?
if (REMOUNT) {
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// check our file with stat
struct lfs_info info;
lfsr_stat(&lfs, "hello", &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
// and with dir read
lfsr_dir_t dir;
lfsr_dir_open(&lfs, &dir, "/") => 0;
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, ".") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "..") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
lfsr_dir_read(&lfs, &dir, &info) => LFS_ERR_NOENT;
lfsr_dir_close(&lfs, &dir) => 0;
// try reading our file
lfsr_file_open(&lfs, &file, "hello", LFS_O_RDONLY) => 0;
// is size correct?
lfsr_file_size(&lfs, &file) => SIZE;
// try reading
uint8_t rbuf[8192];
memset(rbuf, 0xaa, sizeof(rbuf));
lfsr_file_read(&lfs, &file, rbuf, sizeof(rbuf)) => SIZE;
// does our file match our simulation?
assert(memcmp(rbuf, sim, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''
# similar to overwrite files, but without underlying data
[cases.test_ftree_holes]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = ['CACHE_SIZE/2', '4', '1']
# bit 0 => first chunk
# bit 1 => middle chunk
# bit 2 => last chunk
defines.MASK = [4, 5, 6, 7] # TODO 0 1 2 3 ? need truncate?
# 0 => in-order
# 1 => reversed
defines.ORDER = [0] # TODO 1?
defines.SYNC = [false, true]
defines.REMOUNT = [false, true]
reentrant = true
code = '''
// format once per test
lfs_t lfs;
int err = lfsr_mount(&lfs, CFG);
if (err) {
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// create a file, truncating in case of powerloss
lfsr_file_t file;
lfsr_file_open(&lfs, &file, "hello",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => 0;
// simulate our file in ram
uint8_t sim[8192];
uint32_t prng = 42;
memset(sim, 0, SIZE);
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write first chunk?
if (MASK & 1) {
if (ORDER == 0) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, 0, LFS_SEEK_SET) => 0;
lfsr_file_write(&lfs, &file, &sim[0], CHUNK) => CHUNK;
} else {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE-CHUNK+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-CHUNK, LFS_SEEK_SET) => SIZE-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-CHUNK], CHUNK) => CHUNK;
}
}
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write second chunk?
if (MASK & 2) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE/2-CHUNK/2+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE/2 - CHUNK/2, LFS_SEEK_SET)
=> SIZE/2 - CHUNK/2;
lfsr_file_write(&lfs, &file, &sim[SIZE/2-CHUNK/2], CHUNK) => CHUNK;
}
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write third chunk?
if (MASK & 4) {
if (ORDER == 0) {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[SIZE-CHUNK+i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-CHUNK, LFS_SEEK_SET) => SIZE-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-CHUNK], CHUNK) => CHUNK;
} else {
for (lfs_size_t i = 0; i < CHUNK; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, 0, LFS_SEEK_SET) => 0;
lfsr_file_write(&lfs, &file, &sim[0], CHUNK) => CHUNK;
}
}
lfsr_file_close(&lfs, &file) => 0;
// remount?
if (REMOUNT) {
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// check our file with stat
struct lfs_info info;
lfsr_stat(&lfs, "hello", &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
// and with dir read
lfsr_dir_t dir;
lfsr_dir_open(&lfs, &dir, "/") => 0;
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, ".") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "..") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
lfsr_dir_read(&lfs, &dir, &info) => LFS_ERR_NOENT;
lfsr_dir_close(&lfs, &dir) => 0;
// try reading our file
lfsr_file_open(&lfs, &file, "hello", LFS_O_RDONLY) => 0;
// is size correct?
lfsr_file_size(&lfs, &file) => SIZE;
// try reading
uint8_t rbuf[8192];
memset(rbuf, 0xaa, sizeof(rbuf));
lfsr_file_read(&lfs, &file, rbuf, sizeof(rbuf)) => SIZE;
// does our file match our simulation?
assert(memcmp(rbuf, sim, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''
# writing any data structure backwards always reveals issues
[cases.test_ftree_reversed_overwrite]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = ['CACHE_SIZE/2', '4', '1']
defines.SYNC = [false, true]
defines.REMOUNT = [false, true]
reentrant = true
code = '''
// format once per test
lfs_t lfs;
int err = lfsr_mount(&lfs, CFG);
if (err) {
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// create a file, truncating in case of powerloss
lfsr_file_t file;
lfsr_file_open(&lfs, &file, "hello",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => 0;
// simulate our file in ram
uint8_t sim[8192];
uint32_t prng = 42;
for (lfs_size_t i = 0; i < SIZE; i++) {
sim[i] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_write(&lfs, &file, sim, SIZE) => SIZE;
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write to file incrementally and backwards
for (lfs_size_t i = 0; i < SIZE; i += CHUNK) {
for (lfs_size_t j = 0; j < CHUNK; j++) {
sim[SIZE-i-CHUNK+j] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-i-CHUNK, LFS_SEEK_SET) => SIZE-i-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-i-CHUNK], CHUNK) => CHUNK;
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
}
lfsr_file_close(&lfs, &file) => 0;
// remount?
if (REMOUNT) {
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// check our file with stat
struct lfs_info info;
lfsr_stat(&lfs, "hello", &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
// and with dir read
lfsr_dir_t dir;
lfsr_dir_open(&lfs, &dir, "/") => 0;
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, ".") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "..") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
lfsr_dir_read(&lfs, &dir, &info) => LFS_ERR_NOENT;
lfsr_dir_close(&lfs, &dir) => 0;
// try reading our file
lfsr_file_open(&lfs, &file, "hello", LFS_O_RDONLY) => 0;
// is size correct?
lfsr_file_size(&lfs, &file) => SIZE;
// try reading
uint8_t rbuf[8192];
memset(rbuf, 0xaa, sizeof(rbuf));
lfsr_file_read(&lfs, &file, rbuf, sizeof(rbuf)) => SIZE;
// does our file match our simulation?
assert(memcmp(rbuf, sim, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''
# writing any data structure backwards always reveals issues
[cases.test_ftree_reversed_holes]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = ['CACHE_SIZE/2', '4', '1']
defines.SYNC = [false, true]
defines.REMOUNT = [false, true]
reentrant = true
code = '''
// format once per test
lfs_t lfs;
int err = lfsr_mount(&lfs, CFG);
if (err) {
lfsr_format(&lfs, CFG) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// create a file, truncating in case of powerloss
lfsr_file_t file;
lfsr_file_open(&lfs, &file, "hello",
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => 0;
// simulate our file in ram
uint8_t sim[8192];
uint32_t prng = 42;
memset(sim, 0, SIZE);
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
// write to file incrementally and backwards
for (lfs_size_t i = 0; i < SIZE; i += CHUNK) {
for (lfs_size_t j = 0; j < CHUNK; j++) {
sim[SIZE-i-CHUNK+j] = 'a' + (TEST_PRNG(&prng) % 26);
}
lfsr_file_seek(&lfs, &file, SIZE-i-CHUNK, LFS_SEEK_SET) => SIZE-i-CHUNK;
lfsr_file_write(&lfs, &file, &sim[SIZE-i-CHUNK], CHUNK) => CHUNK;
// sync?
if (SYNC) {
lfsr_file_sync(&lfs, &file) => 0;
}
// remount?
if (REMOUNT) {
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
lfsr_file_open(&lfs, &file, "hello", LFS_O_WRONLY) => 0;
}
}
lfsr_file_close(&lfs, &file) => 0;
// remount?
if (REMOUNT) {
lfsr_unmount(&lfs) => 0;
lfsr_mount(&lfs, CFG) => 0;
}
// check our file with stat
struct lfs_info info;
lfsr_stat(&lfs, "hello", &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
// and with dir read
lfsr_dir_t dir;
lfsr_dir_open(&lfs, &dir, "/") => 0;
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, ".") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "..") == 0);
assert(info.type == LFS_TYPE_DIR);
lfsr_dir_read(&lfs, &dir, &info) => 0;
assert(strcmp(info.name, "hello") == 0);
assert(info.type == LFS_TYPE_REG);
assert(info.size == SIZE);
lfsr_dir_read(&lfs, &dir, &info) => LFS_ERR_NOENT;
lfsr_dir_close(&lfs, &dir) => 0;
// try reading our file
lfsr_file_open(&lfs, &file, "hello", LFS_O_RDONLY) => 0;
// is size correct?
lfsr_file_size(&lfs, &file) => SIZE;
// try reading
uint8_t rbuf[8192];
memset(rbuf, 0xaa, sizeof(rbuf));
lfsr_file_read(&lfs, &file, rbuf, sizeof(rbuf)) => SIZE;
// does our file match our simulation?
assert(memcmp(rbuf, sim, SIZE) == 0);
lfsr_file_close(&lfs, &file) => 0;
lfsr_unmount(&lfs) => 0;
'''