third_party_littlefs/tests/test_alloc.toml
Christopher Haster f9dbec3d92 Added test case catching issues with errors during a lookahead scan
Original issue found by thrasher8390
2020-03-29 14:12:58 -05:00

654 lines
21 KiB
TOML

# allocator tests
# note for these to work there are a number constraints on the device geometry
if = 'LFS_BLOCK_CYCLES == -1'
[[case]] # parallel allocation test
define.FILES = 3
define.SIZE = '(((LFS_BLOCK_SIZE-8)*(LFS_BLOCK_COUNT-6)) / FILES)'
code = '''
const char *names[FILES] = {"bacon", "eggs", "pancakes"};
lfs_file_t files[FILES];
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &files[n], path,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
}
for (int n = 0; n < FILES; n++) {
size = strlen(names[n]);
for (lfs_size_t i = 0; i < SIZE; i += size) {
lfs_file_write(&lfs, &files[n], names[n], size) => size;
}
}
for (int n = 0; n < FILES; n++) {
lfs_file_close(&lfs, &files[n]) => 0;
}
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path, LFS_O_RDONLY) => 0;
size = strlen(names[n]);
for (lfs_size_t i = 0; i < SIZE; i += size) {
lfs_file_read(&lfs, &file, buffer, size) => size;
assert(memcmp(buffer, names[n], size) == 0);
}
lfs_file_close(&lfs, &file) => 0;
}
lfs_unmount(&lfs) => 0;
'''
[[case]] # serial allocation test
define.FILES = 3
define.SIZE = '(((LFS_BLOCK_SIZE-8)*(LFS_BLOCK_COUNT-6)) / FILES)'
code = '''
const char *names[FILES] = {"bacon", "eggs", "pancakes"};
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
for (int n = 0; n < FILES; n++) {
lfs_mount(&lfs, &cfg) => 0;
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
size = strlen(names[n]);
memcpy(buffer, names[n], size);
for (int i = 0; i < SIZE; i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
}
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path, LFS_O_RDONLY) => 0;
size = strlen(names[n]);
for (int i = 0; i < SIZE; i += size) {
lfs_file_read(&lfs, &file, buffer, size) => size;
assert(memcmp(buffer, names[n], size) == 0);
}
lfs_file_close(&lfs, &file) => 0;
}
lfs_unmount(&lfs) => 0;
'''
[[case]] # parallel allocation reuse test
define.FILES = 3
define.SIZE = '(((LFS_BLOCK_SIZE-8)*(LFS_BLOCK_COUNT-6)) / FILES)'
define.CYCLES = [1, 10]
code = '''
const char *names[FILES] = {"bacon", "eggs", "pancakes"};
lfs_file_t files[FILES];
lfs_format(&lfs, &cfg) => 0;
for (int c = 0; c < CYCLES; c++) {
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &files[n], path,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
}
for (int n = 0; n < FILES; n++) {
size = strlen(names[n]);
for (int i = 0; i < SIZE; i += size) {
lfs_file_write(&lfs, &files[n], names[n], size) => size;
}
}
for (int n = 0; n < FILES; n++) {
lfs_file_close(&lfs, &files[n]) => 0;
}
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path, LFS_O_RDONLY) => 0;
size = strlen(names[n]);
for (int i = 0; i < SIZE; i += size) {
lfs_file_read(&lfs, &file, buffer, size) => size;
assert(memcmp(buffer, names[n], size) == 0);
}
lfs_file_close(&lfs, &file) => 0;
}
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_remove(&lfs, path) => 0;
}
lfs_remove(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
}
'''
[[case]] # serial allocation reuse test
define.FILES = 3
define.SIZE = '(((LFS_BLOCK_SIZE-8)*(LFS_BLOCK_COUNT-6)) / FILES)'
define.CYCLES = [1, 10]
code = '''
const char *names[FILES] = {"bacon", "eggs", "pancakes"};
lfs_format(&lfs, &cfg) => 0;
for (int c = 0; c < CYCLES; c++) {
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
for (int n = 0; n < FILES; n++) {
lfs_mount(&lfs, &cfg) => 0;
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
size = strlen(names[n]);
memcpy(buffer, names[n], size);
for (int i = 0; i < SIZE; i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
}
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_file_open(&lfs, &file, path, LFS_O_RDONLY) => 0;
size = strlen(names[n]);
for (int i = 0; i < SIZE; i += size) {
lfs_file_read(&lfs, &file, buffer, size) => size;
assert(memcmp(buffer, names[n], size) == 0);
}
lfs_file_close(&lfs, &file) => 0;
}
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
for (int n = 0; n < FILES; n++) {
sprintf(path, "breakfast/%s", names[n]);
lfs_remove(&lfs, path) => 0;
}
lfs_remove(&lfs, "breakfast") => 0;
lfs_unmount(&lfs) => 0;
}
'''
[[case]] # exhaustion test
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
size = strlen("exhaustion");
memcpy(buffer, "exhaustion", size);
lfs_file_write(&lfs, &file, buffer, size) => size;
lfs_file_sync(&lfs, &file) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
lfs_ssize_t res;
while (true) {
res = lfs_file_write(&lfs, &file, buffer, size);
if (res < 0) {
break;
}
res => size;
}
res => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_RDONLY);
size = strlen("exhaustion");
lfs_file_size(&lfs, &file) => size;
lfs_file_read(&lfs, &file, buffer, size) => size;
memcmp(buffer, "exhaustion", size) => 0;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # exhaustion wraparound test
define.SIZE = '(((LFS_BLOCK_SIZE-8)*(LFS_BLOCK_COUNT-4)) / 3)'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file, "padding", LFS_O_WRONLY | LFS_O_CREAT);
size = strlen("buffering");
memcpy(buffer, "buffering", size);
for (int i = 0; i < SIZE; i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_remove(&lfs, "padding") => 0;
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
size = strlen("exhaustion");
memcpy(buffer, "exhaustion", size);
lfs_file_write(&lfs, &file, buffer, size) => size;
lfs_file_sync(&lfs, &file) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
lfs_ssize_t res;
while (true) {
res = lfs_file_write(&lfs, &file, buffer, size);
if (res < 0) {
break;
}
res => size;
}
res => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_RDONLY);
size = strlen("exhaustion");
lfs_file_size(&lfs, &file) => size;
lfs_file_read(&lfs, &file, buffer, size) => size;
memcmp(buffer, "exhaustion", size) => 0;
lfs_file_close(&lfs, &file) => 0;
lfs_remove(&lfs, "exhaustion") => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # dir exhaustion test
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// find out max file size
lfs_mkdir(&lfs, "exhaustiondir") => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
int count = 0;
while (true) {
err = lfs_file_write(&lfs, &file, buffer, size);
if (err < 0) {
break;
}
count += 1;
}
err => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_remove(&lfs, "exhaustion") => 0;
lfs_remove(&lfs, "exhaustiondir") => 0;
// see if dir fits with max file size
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
for (int i = 0; i < count; i++) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_mkdir(&lfs, "exhaustiondir") => 0;
lfs_remove(&lfs, "exhaustiondir") => 0;
lfs_remove(&lfs, "exhaustion") => 0;
// see if dir fits with > max file size
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
for (int i = 0; i < count+1; i++) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_mkdir(&lfs, "exhaustiondir") => LFS_ERR_NOSPC;
lfs_remove(&lfs, "exhaustion") => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # what if we have a bad block during an allocation scan?
in = "lfs.c"
define.LFS_ERASE_CYCLES = 0xffffffff
define.LFS_BADBLOCK_BEHAVIOR = 'LFS_TESTBD_BADBLOCK_READERROR'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// first fill to exhaustion to find available space
lfs_file_open(&lfs, &file, "pacman", LFS_O_WRONLY | LFS_O_CREAT) => 0;
strcpy((char*)buffer, "waka");
size = strlen("waka");
lfs_size_t filesize = 0;
while (true) {
lfs_ssize_t res = lfs_file_write(&lfs, &file, buffer, size);
assert(res == (lfs_ssize_t)size || res == LFS_ERR_NOSPC);
if (res == LFS_ERR_NOSPC) {
break;
}
filesize += size;
}
lfs_file_close(&lfs, &file) => 0;
// now fill all but a couple of blocks of the filesystem with data
filesize -= 3*LFS_BLOCK_SIZE;
lfs_file_open(&lfs, &file, "pacman", LFS_O_WRONLY | LFS_O_CREAT) => 0;
strcpy((char*)buffer, "waka");
size = strlen("waka");
for (lfs_size_t i = 0; i < filesize/size; i++) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// also save head of file so we can error during lookahead scan
lfs_block_t fileblock = file.ctz.head;
lfs_unmount(&lfs) => 0;
// remount to force an alloc scan
lfs_mount(&lfs, &cfg) => 0;
// but mark the head of our file as a "bad block", this is force our
// scan to bail early
lfs_testbd_setwear(&cfg, fileblock, 0xffffffff) => 0;
lfs_file_open(&lfs, &file, "ghost", LFS_O_WRONLY | LFS_O_CREAT) => 0;
strcpy((char*)buffer, "chomp");
size = strlen("chomp");
while (true) {
lfs_ssize_t res = lfs_file_write(&lfs, &file, buffer, size);
assert(res == (lfs_ssize_t)size || res == LFS_ERR_CORRUPT);
if (res == LFS_ERR_CORRUPT) {
break;
}
}
lfs_file_close(&lfs, &file) => 0;
// now reverse the "bad block" and try to write the file again until we
// run out of space
lfs_testbd_setwear(&cfg, fileblock, 0) => 0;
lfs_file_open(&lfs, &file, "ghost", LFS_O_WRONLY | LFS_O_CREAT) => 0;
strcpy((char*)buffer, "chomp");
size = strlen("chomp");
while (true) {
lfs_ssize_t res = lfs_file_write(&lfs, &file, buffer, size);
assert(res == (lfs_ssize_t)size || res == LFS_ERR_NOSPC);
if (res == LFS_ERR_NOSPC) {
break;
}
}
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
// check that the disk isn't hurt
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file, "pacman", LFS_O_RDONLY) => 0;
strcpy((char*)buffer, "waka");
size = strlen("waka");
for (lfs_size_t i = 0; i < filesize/size; i++) {
uint8_t rbuffer[4];
lfs_file_read(&lfs, &file, rbuffer, size) => size;
assert(memcmp(rbuffer, buffer, size) == 0);
}
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
# Below, I don't like these tests. They're fragile and depend _heavily_
# on the geometry of the block device. But they are valuable. Eventually they
# should be removed and replaced with generalized tests.
[[case]] # chained dir exhaustion test
define.LFS_BLOCK_SIZE = 512
define.LFS_BLOCK_COUNT = 1024
if = 'LFS_BLOCK_SIZE == 512 && LFS_BLOCK_COUNT == 1024'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// find out max file size
lfs_mkdir(&lfs, "exhaustiondir") => 0;
for (int i = 0; i < 10; i++) {
sprintf(path, "dirwithanexhaustivelylongnameforpadding%d", i);
lfs_mkdir(&lfs, path) => 0;
}
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
int count = 0;
while (true) {
err = lfs_file_write(&lfs, &file, buffer, size);
if (err < 0) {
break;
}
count += 1;
}
err => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_remove(&lfs, "exhaustion") => 0;
lfs_remove(&lfs, "exhaustiondir") => 0;
for (int i = 0; i < 10; i++) {
sprintf(path, "dirwithanexhaustivelylongnameforpadding%d", i);
lfs_remove(&lfs, path) => 0;
}
// see that chained dir fails
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
for (int i = 0; i < count+1; i++) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_sync(&lfs, &file) => 0;
for (int i = 0; i < 10; i++) {
sprintf(path, "dirwithanexhaustivelylongnameforpadding%d", i);
lfs_mkdir(&lfs, path) => 0;
}
lfs_mkdir(&lfs, "exhaustiondir") => LFS_ERR_NOSPC;
// shorten file to try a second chained dir
while (true) {
err = lfs_mkdir(&lfs, "exhaustiondir");
if (err != LFS_ERR_NOSPC) {
break;
}
lfs_ssize_t filesize = lfs_file_size(&lfs, &file);
filesize > 0 => true;
lfs_file_truncate(&lfs, &file, filesize - size) => 0;
lfs_file_sync(&lfs, &file) => 0;
}
err => 0;
lfs_mkdir(&lfs, "exhaustiondir2") => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # split dir test
define.LFS_BLOCK_SIZE = 512
define.LFS_BLOCK_COUNT = 1024
if = 'LFS_BLOCK_SIZE == 512 && LFS_BLOCK_COUNT == 1024'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// create one block hole for half a directory
lfs_file_open(&lfs, &file, "bump", LFS_O_WRONLY | LFS_O_CREAT) => 0;
for (lfs_size_t i = 0; i < cfg.block_size; i += 2) {
memcpy(&buffer[i], "hi", 2);
}
lfs_file_write(&lfs, &file, buffer, cfg.block_size) => cfg.block_size;
lfs_file_close(&lfs, &file) => 0;
lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < (cfg.block_count-4)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// remount to force reset of lookahead
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
// open hole
lfs_remove(&lfs, "bump") => 0;
lfs_mkdir(&lfs, "splitdir") => 0;
lfs_file_open(&lfs, &file, "splitdir/bump",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
for (lfs_size_t i = 0; i < cfg.block_size; i += 2) {
memcpy(&buffer[i], "hi", 2);
}
lfs_file_write(&lfs, &file, buffer, 2*cfg.block_size) => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # outdated lookahead test
define.LFS_BLOCK_SIZE = 512
define.LFS_BLOCK_COUNT = 1024
if = 'LFS_BLOCK_SIZE == 512 && LFS_BLOCK_COUNT == 1024'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// fill completely with two files
lfs_file_open(&lfs, &file, "exhaustion1",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_file_open(&lfs, &file, "exhaustion2",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// remount to force reset of lookahead
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
// rewrite one file
lfs_file_open(&lfs, &file, "exhaustion1",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// rewrite second file, this requires lookahead does not
// use old population
lfs_file_open(&lfs, &file, "exhaustion2",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''
[[case]] # outdated lookahead and split dir test
define.LFS_BLOCK_SIZE = 512
define.LFS_BLOCK_COUNT = 1024
if = 'LFS_BLOCK_SIZE == 512 && LFS_BLOCK_COUNT == 1024'
code = '''
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// fill completely with two files
lfs_file_open(&lfs, &file, "exhaustion1",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
lfs_file_open(&lfs, &file, "exhaustion2",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// remount to force reset of lookahead
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
// rewrite one file with a hole of one block
lfs_file_open(&lfs, &file, "exhaustion1",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-2)/2 - 1)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file, buffer, size) => size;
}
lfs_file_close(&lfs, &file) => 0;
// try to allocate a directory, should fail!
lfs_mkdir(&lfs, "split") => LFS_ERR_NOSPC;
// file should not fail
lfs_file_open(&lfs, &file, "notasplit",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
lfs_file_write(&lfs, &file, "hi", 2) => 2;
lfs_file_close(&lfs, &file) => 0;
lfs_unmount(&lfs) => 0;
'''