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Author SHA1 Message Date
Christopher Haster
ebc0d24211 Added conversion to/from little-endian on disk
Required to support big-endian processors, with the most notable being
the PowerPC architecture.

On little-endian architectures, these conversions can be optimized out
and have no code impact.

Initial patch provided by gmouchard
2018-02-15 16:33:03 -06:00
Christopher Haster
dbce53672b Added conversion to/from little endian on disk
patch provided by gmouchard
2018-02-04 11:51:23 -06:00
22 changed files with 804 additions and 1421 deletions

9
.gitignore vendored
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@@ -1,9 +0,0 @@
# Compilation output
*.o
*.d
*.a
# Testing things
blocks/
lfs
test.c

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@@ -1,229 +1,47 @@
# Environment variables
env:
global:
- CFLAGS=-Werror
# Common test script
script:
# make sure example can at least compile
- sed -n '/``` c/,/```/{/```/d; p;}' README.md > test.c &&
make all CFLAGS+="
# make sure example can at least compile
- sed -n '/``` c/,/```/{/```/d; p;}' README.md > test.c &&
CFLAGS='
-Duser_provided_block_device_read=NULL
-Duser_provided_block_device_prog=NULL
-Duser_provided_block_device_erase=NULL
-Duser_provided_block_device_sync=NULL
-include stdio.h"
-include stdio.h -Werror' make all size
# run tests
- make test QUIET=1
# run tests
- make test QUIET=1
# run tests with a few different configurations
- make test QUIET=1 CFLAGS+="-DLFS_READ_SIZE=1 -DLFS_PROG_SIZE=1"
- make test QUIET=1 CFLAGS+="-DLFS_READ_SIZE=512 -DLFS_PROG_SIZE=512"
- make test QUIET=1 CFLAGS+="-DLFS_BLOCK_COUNT=1023 -DLFS_LOOKAHEAD=2048"
- make clean test QUIET=1 CFLAGS+="-DLFS_NO_INTRINSICS"
# compile and find the code size with the smallest configuration
- make clean size
OBJ="$(ls lfs*.o | tr '\n' ' ')"
CFLAGS+="-DLFS_NO_ASSERT -DLFS_NO_DEBUG -DLFS_NO_WARN -DLFS_NO_ERROR"
| tee sizes
# update status if we succeeded, compare with master if possible
- |
if [ "$TRAVIS_TEST_RESULT" -eq 0 ]
then
CURR=$(tail -n1 sizes | awk '{print $1}')
PREV=$(curl -u $GEKY_BOT_STATUSES https://api.github.com/repos/$TRAVIS_REPO_SLUG/status/master \
| jq -re "select(.sha != \"$TRAVIS_COMMIT\")
| .statuses[] | select(.context == \"$STAGE/$NAME\").description
| capture(\"code size is (?<size>[0-9]+)\").size" \
|| echo 0)
STATUS="Passed, code size is ${CURR}B"
if [ "$PREV" -ne 0 ]
then
STATUS="$STATUS ($(python -c "print '%+.2f' % (100*($CURR-$PREV)/$PREV.0)")%)"
fi
fi
# CI matrix
jobs:
include:
# native testing
- stage: test
env:
- STAGE=test
- NAME=littlefs-x86
# cross-compile with ARM (thumb mode)
- stage: test
env:
- STAGE=test
- NAME=littlefs-arm
- CC="arm-linux-gnueabi-gcc --static -mthumb"
- EXEC="qemu-arm"
install:
- sudo apt-get install gcc-arm-linux-gnueabi qemu-user
- arm-linux-gnueabi-gcc --version
- qemu-arm -version
# cross-compile with PowerPC
- stage: test
env:
- STAGE=test
- NAME=littlefs-powerpc
- CC="powerpc-linux-gnu-gcc --static"
- EXEC="qemu-ppc"
install:
- sudo apt-get install gcc-powerpc-linux-gnu qemu-user
- powerpc-linux-gnu-gcc --version
- qemu-ppc -version
# cross-compile with MIPS
- stage: test
env:
- STAGE=test
- NAME=littlefs-mips
- CC="mips-linux-gnu-gcc --static"
- EXEC="qemu-mips"
install:
- sudo add-apt-repository -y "deb http://archive.ubuntu.com/ubuntu/ xenial main universe"
- sudo apt-get -qq update
- sudo apt-get install gcc-mips-linux-gnu qemu-user
- mips-linux-gnu-gcc --version
- qemu-mips -version
# run tests with a few different configurations
- CFLAGS="-DLFS_READ_SIZE=1 -DLFS_PROG_SIZE=1" make test QUIET=1
- CFLAGS="-DLFS_READ_SIZE=512 -DLFS_PROG_SIZE=512" make test QUIET=1
- CFLAGS="-DLFS_BLOCK_COUNT=1023 -DLFS_LOOKAHEAD=2048" make test QUIET=1
# self-host with littlefs-fuse for fuzz test
- stage: test
env:
- STAGE=test
- NAME=littlefs-fuse
install:
- sudo apt-get install libfuse-dev
- git clone --depth 1 https://github.com/geky/littlefs-fuse
- fusermount -V
- gcc --version
before_script:
# setup disk for littlefs-fuse
- rm -rf littlefs-fuse/littlefs/*
- cp -r $(git ls-tree --name-only HEAD) littlefs-fuse/littlefs
- make -C littlefs-fuse
- mkdir mount
- sudo chmod a+rw /dev/loop0
- dd if=/dev/zero bs=512 count=2048 of=disk
- losetup /dev/loop0 disk
script:
# self-host test
- make -C littlefs-fuse
- littlefs-fuse/lfs --format /dev/loop0
- littlefs-fuse/lfs /dev/loop0 mount
- littlefs-fuse/lfs --format /dev/loop0
- littlefs-fuse/lfs /dev/loop0 mount
- ls mount
- mkdir mount/littlefs
- cp -r $(git ls-tree --name-only HEAD) mount/littlefs
- cd mount/littlefs
- ls
- make -B test_dirs test_files QUIET=1
- ls mount
- mkdir mount/littlefs
- cp -r $(git ls-tree --name-only HEAD) mount/littlefs
- cd mount/littlefs
- ls
- make -B test_dirs test_files QUIET=1
# Automatically update releases
- stage: deploy
env:
- STAGE=deploy
- NAME=deploy
script:
# Find version defined in lfs.h
- LFS_VERSION=$(grep -ox '#define LFS_VERSION .*' lfs.h | cut -d ' ' -f3)
- LFS_VERSION_MAJOR=$((0xffff & ($LFS_VERSION >> 16)))
- LFS_VERSION_MINOR=$((0xffff & ($LFS_VERSION >> 0)))
# Grab latests patch from repo tags, default to 0, needs finagling to get past github's pagination api
- PREV_URL=https://api.github.com/repos/$TRAVIS_REPO_SLUG/git/refs/tags/v$LFS_VERSION_MAJOR.$LFS_VERSION_MINOR.
- PREV_URL=$(curl -u "$GEKY_BOT_RELEASES" "$PREV_URL" -I
| sed -n '/^Link/{s/.*<\(.*\)>; rel="last"/\1/;p;q0};$q1'
|| echo $PREV_URL)
- LFS_VERSION_PATCH=$(curl -u "$GEKY_BOT_RELEASES" "$PREV_URL"
| jq 'map(.ref | match("\\bv.*\\..*\\.(.*)$";"g")
.captures[].string | tonumber) | max + 1'
|| echo 0)
# We have our new version
- LFS_VERSION="v$LFS_VERSION_MAJOR.$LFS_VERSION_MINOR.$LFS_VERSION_PATCH"
- echo "VERSION $LFS_VERSION"
- |
# Check that we're the most recent commit
CURRENT_COMMIT=$(curl -f -u "$GEKY_BOT_RELEASES" \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/commits/master \
| jq -re '.sha')
if [ "$TRAVIS_COMMIT" == "$CURRENT_COMMIT" ]
then
# Create a simple tag
curl -f -u "$GEKY_BOT_RELEASES" -X POST \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/git/refs \
-d "{
\"ref\": \"refs/tags/$LFS_VERSION\",
\"sha\": \"$TRAVIS_COMMIT\"
}"
# Minor release?
if [[ "$LFS_VERSION" == *.0 ]]
then
# Build release notes
PREV=$(git tag --sort=-v:refname -l "v*.0" | head -1)
if [ ! -z "$PREV" ]
then
echo "PREV $PREV"
CHANGES=$'### Changes\n\n'$( \
git log --oneline $PREV.. --grep='^Merge' --invert-grep)
printf "CHANGES\n%s\n\n" "$CHANGES"
fi
# Create the release
curl -f -u "$GEKY_BOT_RELEASES" -X POST \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases \
-d "{
\"tag_name\": \"$LFS_VERSION\",
\"name\": \"${LFS_VERSION%.0}\",
\"draft\": true,
\"body\": $(jq -sR '.' <<< "$CHANGES")
}"
fi
fi
# Manage statuses
before_install:
- |
curl -u $GEKY_BOT_STATUSES -X POST \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/statuses/${TRAVIS_PULL_REQUEST_SHA:-$TRAVIS_COMMIT} \
-d "{
\"context\": \"$STAGE/$NAME\",
\"state\": \"pending\",
\"description\": \"${STATUS:-In progress}\",
\"target_url\": \"https://travis-ci.org/$TRAVIS_REPO_SLUG/jobs/$TRAVIS_JOB_ID\"
}"
- fusermount -V
- gcc --version
after_failure:
- |
curl -u $GEKY_BOT_STATUSES -X POST \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/statuses/${TRAVIS_PULL_REQUEST_SHA:-$TRAVIS_COMMIT} \
-d "{
\"context\": \"$STAGE/$NAME\",
\"state\": \"failure\",
\"description\": \"${STATUS:-Failed}\",
\"target_url\": \"https://travis-ci.org/$TRAVIS_REPO_SLUG/jobs/$TRAVIS_JOB_ID\"
}"
install:
- sudo apt-get install libfuse-dev
- git clone --depth 1 https://github.com/geky/littlefs-fuse
after_success:
- |
curl -u $GEKY_BOT_STATUSES -X POST \
https://api.github.com/repos/$TRAVIS_REPO_SLUG/statuses/${TRAVIS_PULL_REQUEST_SHA:-$TRAVIS_COMMIT} \
-d "{
\"context\": \"$STAGE/$NAME\",
\"state\": \"success\",
\"description\": \"${STATUS:-Passed}\",
\"target_url\": \"https://travis-ci.org/$TRAVIS_REPO_SLUG/jobs/$TRAVIS_JOB_ID\"
}"
before_script:
- rm -rf littlefs-fuse/littlefs/*
- cp -r $(git ls-tree --name-only HEAD) littlefs-fuse/littlefs
# Job control
stages:
- name: test
- name: deploy
if: branch = master AND type = push
- mkdir mount
- sudo chmod a+rw /dev/loop0
- dd if=/dev/zero bs=512 count=2048 of=disk
- losetup /dev/loop0 disk

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@@ -27,17 +27,16 @@ cheap, and can be very granular. For NOR flash specifically, byte-level
programs are quite common. Erasing, however, requires an expensive operation
that forces the state of large blocks of memory to reset in a destructive
reaction that gives flash its name. The [Wikipedia entry](https://en.wikipedia.org/wiki/Flash_memory)
has more information if you are interested in how this works.
has more information if you are interesting in how this works.
This leaves us with an interesting set of limitations that can be simplified
to three strong requirements:
1. **Power-loss resilient** - This is the main goal of the littlefs and the
focus of this project.
Embedded systems are usually designed without a shutdown routine and a
notable lack of user interface for recovery, so filesystems targeting
embedded systems must be prepared to lose power at any given time.
focus of this project. Embedded systems are usually designed without a
shutdown routine and a notable lack of user interface for recovery, so
filesystems targeting embedded systems must be prepared to lose power an
any given time.
Despite this state of things, there are very few embedded filesystems that
handle power loss in a reasonable manner, and most can become corrupted if
@@ -53,8 +52,7 @@ to three strong requirements:
which stores a file allocation table (FAT) at a specific offset from the
beginning of disk. Every block allocation will update this table, and after
100,000 updates, the block will likely go bad, rendering the filesystem
unusable even if there are many more erase cycles available on the storage
as a whole.
unusable even if there are many more erase cycles available on the storage.
3. **Bounded RAM/ROM** - Even with the design difficulties presented by the
previous two limitations, we have already seen several flash filesystems
@@ -74,7 +72,7 @@ to three strong requirements:
## Existing designs?
There are of course, many different existing filesystem. Here is a very rough
There are of course, many different existing filesystem. Heres a very rough
summary of the general ideas behind some of them.
Most of the existing filesystems fall into the one big category of filesystem
@@ -82,21 +80,21 @@ designed in the early days of spinny magnet disks. While there is a vast amount
of interesting technology and ideas in this area, the nature of spinny magnet
disks encourage properties, such as grouping writes near each other, that don't
make as much sense on recent storage types. For instance, on flash, write
locality is not important and can actually increase wear.
locality is not important and can actually increase wear destructively.
One of the most popular designs for flash filesystems is called the
[logging filesystem](https://en.wikipedia.org/wiki/Log-structured_file_system).
The flash filesystems [jffs](https://en.wikipedia.org/wiki/JFFS)
and [yaffs](https://en.wikipedia.org/wiki/YAFFS) are good examples. In a
logging filesystem, data is not stored in a data structure on disk, but instead
and [yaffs](https://en.wikipedia.org/wiki/YAFFS) are good examples. In
logging filesystem, data is not store in a data structure on disk, but instead
the changes to the files are stored on disk. This has several neat advantages,
such as the fact that the data is written in a cyclic log format and naturally
such as the fact that the data is written in a cyclic log format naturally
wear levels as a side effect. And, with a bit of error detection, the entire
filesystem can easily be designed to be resilient to power loss. The
journaling component of most modern day filesystems is actually a reduced
journalling component of most modern day filesystems is actually a reduced
form of a logging filesystem. However, logging filesystems have a difficulty
scaling as the size of storage increases. And most filesystems compensate by
caching large parts of the filesystem in RAM, a strategy that is inappropriate
caching large parts of the filesystem in RAM, a strategy that is unavailable
for embedded systems.
Another interesting filesystem design technique is that of [copy-on-write (COW)](https://en.wikipedia.org/wiki/Copy-on-write).
@@ -109,14 +107,14 @@ where the COW data structures are synchronized.
## Metadata pairs
The core piece of technology that provides the backbone for the littlefs is
the concept of metadata pairs. The key idea here is that any metadata that
the concept of metadata pairs. The key idea here, is that any metadata that
needs to be updated atomically is stored on a pair of blocks tagged with
a revision count and checksum. Every update alternates between these two
pairs, so that at any time there is always a backup containing the previous
state of the metadata.
Consider a small example where each metadata pair has a revision count,
a number as data, and the XOR of the block as a quick checksum. If
a number as data, and the xor of the block as a quick checksum. If
we update the data to a value of 9, and then to a value of 5, here is
what the pair of blocks may look like after each update:
```
@@ -132,7 +130,7 @@ what the pair of blocks may look like after each update:
After each update, we can find the most up to date value of data by looking
at the revision count.
Now consider what the blocks may look like if we suddenly lose power while
Now consider what the blocks may look like if we suddenly loss power while
changing the value of data to 5:
```
block 1 block 2 block 1 block 2 block 1 block 2
@@ -151,7 +149,7 @@ check our checksum we notice that block 1 was corrupted. So we fall back to
block 2 and use the value 9.
Using this concept, the littlefs is able to update metadata blocks atomically.
There are a few other tweaks, such as using a 32 bit CRC and using sequence
There are a few other tweaks, such as using a 32 bit crc and using sequence
arithmetic to handle revision count overflow, but the basic concept
is the same. These metadata pairs define the backbone of the littlefs, and the
rest of the filesystem is built on top of these atomic updates.
@@ -163,7 +161,7 @@ requires two blocks for each block of data. I'm sure users would be very
unhappy if their storage was suddenly cut in half! Instead of storing
everything in these metadata blocks, the littlefs uses a COW data structure
for files which is in turn pointed to by a metadata block. When
we update a file, we create copies of any blocks that are modified until
we update a file, we create a copies of any blocks that are modified until
the metadata blocks are updated with the new copy. Once the metadata block
points to the new copy, we deallocate the old blocks that are no longer in use.
@@ -186,7 +184,7 @@ Here is what updating a one-block file may look like:
update data in file update metadata pair
```
It doesn't matter if we lose power while writing new data to block 5,
It doesn't matter if we lose power while writing block 5 with the new data,
since the old data remains unmodified in block 4. This example also
highlights how the atomic updates of the metadata blocks provide a
synchronization barrier for the rest of the littlefs.
@@ -208,7 +206,7 @@ files in filesystems. Of these, the littlefs uses a rather unique [COW](https://
data structure that allows the filesystem to reuse unmodified parts of the
file without additional metadata pairs.
First lets consider storing files in a simple linked-list. What happens when we
First lets consider storing files in a simple linked-list. What happens when
append a block? We have to change the last block in the linked-list to point
to this new block, which means we have to copy out the last block, and change
the second-to-last block, and then the third-to-last, and so on until we've
@@ -242,8 +240,8 @@ Exhibit B: A backwards linked-list
```
However, a backwards linked-list does come with a rather glaring problem.
Iterating over a file _in order_ has a runtime cost of O(n^2). Gah! A quadratic
runtime to just _read_ a file? That's awful. Keep in mind reading files is
Iterating over a file _in order_ has a runtime of O(n^2). Gah! A quadratic
runtime to just _read_ a file? That's awful. Keep in mind reading files are
usually the most common filesystem operation.
To avoid this problem, the littlefs uses a multilayered linked-list. For
@@ -268,7 +266,7 @@ Exhibit C: A backwards CTZ skip-list
```
The additional pointers allow us to navigate the data-structure on disk
much more efficiently than in a singly linked-list.
much more efficiently than in a single linked-list.
Taking exhibit C for example, here is the path from data block 5 to data
block 1. You can see how data block 3 was completely skipped:
@@ -291,15 +289,15 @@ The path to data block 0 is even more quick, requiring only two jumps:
We can find the runtime complexity by looking at the path to any block from
the block containing the most pointers. Every step along the path divides
the search space for the block in half. This gives us a runtime of O(log n).
the search space for the block in half. This gives us a runtime of O(logn).
To get to the block with the most pointers, we can perform the same steps
backwards, which puts the runtime at O(2 log n) = O(log n). The interesting
backwards, which puts the runtime at O(2logn) = O(logn). The interesting
part about this data structure is that this optimal path occurs naturally
if we greedily choose the pointer that covers the most distance without passing
our target block.
So now we have a representation of files that can be appended trivially with
a runtime of O(1), and can be read with a worst case runtime of O(n log n).
a runtime of O(1), and can be read with a worst case runtime of O(nlogn).
Given that the the runtime is also divided by the amount of data we can store
in a block, this is pretty reasonable.
@@ -364,7 +362,7 @@ N = file size in bytes
And this works quite well, but is not trivial to calculate. This equation
requires O(n) to compute, which brings the entire runtime of reading a file
to O(n^2 log n). Fortunately, the additional O(n) does not need to touch disk,
to O(n^2logn). Fortunately, the additional O(n) does not need to touch disk,
so it is not completely unreasonable. But if we could solve this equation into
a form that is easily computable, we can avoid a big slowdown.
@@ -381,11 +379,11 @@ unintuitive property:
![mindblown](https://latex.codecogs.com/svg.latex?%5Csum_i%5En%5Cleft%28%5Ctext%7Bctz%7D%28i%29&plus;1%5Cright%29%20%3D%202n-%5Ctext%7Bpopcount%7D%28n%29)
where:
ctz(x) = the number of trailing bits that are 0 in x
popcount(x) = the number of bits that are 1 in x
ctz(i) = the number of trailing bits that are 0 in i
popcount(i) = the number of bits that are 1 in i
It's a bit bewildering that these two seemingly unrelated bitwise instructions
are related by this property. But if we start to dissect this equation we can
are related by this property. But if we start to disect this equation we can
see that it does hold. As n approaches infinity, we do end up with an average
overhead of 2 pointers as we find earlier. And popcount seems to handle the
error from this average as it accumulates in the CTZ skip-list.
@@ -412,7 +410,8 @@ a bit to avoid integer overflow:
![formulaforoff](https://latex.codecogs.com/svg.latex?%5Cmathit%7Boff%7D%20%3D%20N%20-%20%5Cleft%28B-2%5Cfrac%7Bw%7D%7B8%7D%5Cright%29n%20-%20%5Cfrac%7Bw%7D%7B8%7D%5Ctext%7Bpopcount%7D%28n%29)
The solution involves quite a bit of math, but computers are very good at math.
Now we can solve for both the block index and offset from the file size in O(1).
We can now solve for the block index + offset while only needed to store the
file size in O(1).
Here is what it might look like to update a file stored with a CTZ skip-list:
```
@@ -501,17 +500,16 @@ scanned to find the most recent free list, but once the list was found the
state of all free blocks becomes known.
However, this approach had several issues:
- There was a lot of nuanced logic for adding blocks to the free list without
modifying the blocks, since the blocks remain active until the metadata is
updated.
- The free list had to support both additions and removals in FIFO order while
- The free list had to support both additions and removals in fifo order while
minimizing block erases.
- The free list had to handle the case where the file system completely ran
out of blocks and may no longer be able to add blocks to the free list.
- If we used a revision count to track the most recently updated free list,
metadata blocks that were left unmodified were ticking time bombs that would
cause the system to go haywire if the revision count overflowed.
cause the system to go haywire if the revision count overflowed
- Every single metadata block wasted space to store these free list references.
Actually, to simplify, this approach had one massive glaring issue: complexity.
@@ -541,7 +539,7 @@ would have an abhorrent runtime.
So the littlefs compromises. It doesn't store a bitmap the size of the storage,
but it does store a little bit-vector that contains a fixed set lookahead
for block allocations. During a block allocation, the lookahead vector is
checked for any free blocks. If there are none, the lookahead region jumps
checked for any free blocks, if there are none, the lookahead region jumps
forward and the entire filesystem is scanned for free blocks.
Here's what it might look like to allocate 4 blocks on a decently busy
@@ -624,7 +622,7 @@ So, as a solution, the littlefs adopted a sort of threaded tree. Each
directory not only contains pointers to all of its children, but also a
pointer to the next directory. These pointers create a linked-list that
is threaded through all of the directories in the filesystem. Since we
only use this linked list to check for existence, the order doesn't actually
only use this linked list to check for existance, the order doesn't actually
matter. As an added plus, we can repurpose the pointer for the individual
directory linked-lists and avoid using any additional space.
@@ -775,7 +773,7 @@ deorphan step that simply iterates through every directory in the linked-list
and checks it against every directory entry in the filesystem to see if it
has a parent. The deorphan step occurs on the first block allocation after
boot, so orphans should never cause the littlefs to run out of storage
prematurely. Note that the deorphan step never needs to run in a read-only
prematurely. Note that the deorphan step never needs to run in a readonly
filesystem.
## The move problem
@@ -885,7 +883,7 @@ a power loss will occur during filesystem activity. We still need to handle
the condition, but runtime during a power loss takes a back seat to the runtime
during normal operations.
So what littlefs does is inelegantly simple. When littlefs moves a file, it
So what littlefs does is unelegantly simple. When littlefs moves a file, it
marks the file as "moving". This is stored as a single bit in the directory
entry and doesn't take up much space. Then littlefs moves the directory,
finishing with the complete remove of the "moving" directory entry.
@@ -981,7 +979,7 @@ if it exists elsewhere in the filesystem.
So now that we have all of the pieces of a filesystem, we can look at a more
subtle attribute of embedded storage: The wear down of flash blocks.
The first concern for the littlefs, is that perfectly valid blocks can suddenly
The first concern for the littlefs, is that prefectly valid blocks can suddenly
become unusable. As a nice side-effect of using a COW data-structure for files,
we can simply move on to a different block when a file write fails. All
modifications to files are performed in copies, so we will only replace the
@@ -1153,7 +1151,7 @@ develops errors and needs to be moved.
## Wear leveling
The second concern for the littlefs is that blocks in the filesystem may wear
The second concern for the littlefs, is that blocks in the filesystem may wear
unevenly. In this situation, a filesystem may meet an early demise where
there are no more non-corrupted blocks that aren't in use. It's common to
have files that were written once and left unmodified, wasting the potential
@@ -1173,7 +1171,7 @@ of wear leveling:
In littlefs's case, it's possible to use the revision count on metadata pairs
to approximate the wear of a metadata block. And combined with the COW nature
of files, littlefs could provide your usual implementation of dynamic wear
of files, littlefs could provide your usually implementation of dynamic wear
leveling.
However, the littlefs does not. This is for a few reasons. Most notably, even
@@ -1212,9 +1210,9 @@ So, to summarize:
metadata block is active
4. Directory blocks contain either references to other directories or files
5. Files are represented by copy-on-write CTZ skip-lists which support O(1)
append and O(n log n) reading
append and O(nlogn) reading
6. Blocks are allocated by scanning the filesystem for used blocks in a
fixed-size lookahead region that is stored in a bit-vector
fixed-size lookahead region is that stored in a bit-vector
7. To facilitate scanning the filesystem, all directories are part of a
linked-list that is threaded through the entire filesystem
8. If a block develops an error, the littlefs allocates a new block, and

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@@ -1,24 +1,165 @@
Copyright (c) 2017, Arm Limited. All rights reserved.
Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
- Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
- 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.
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7. Disclaimer of Warranty.
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NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are
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8. Limitation of Liability.
In no event and under no legal theory, whether in tort (including negligence),
contract, or otherwise, unless required by applicable law (such as deliberate
and grossly negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special, incidental,
or consequential damages of any character arising as a result of this License or
out of the use or inability to use the Work (including but not limited to
damages for loss of goodwill, work stoppage, computer failure or malfunction, or
any and all other commercial damages or losses), even if such Contributor has
been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability.
While redistributing the Work or Derivative Works thereof, You may choose to
offer, and charge a fee for, acceptance of support, warranty, indemnity, or
other liability obligations and/or rights consistent with this License. However,
in accepting such obligations, You may act only on Your own behalf and on Your
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accepting any such warranty or additional liability.

View File

@@ -1,11 +1,8 @@
TARGET = lfs.a
ifneq ($(wildcard test.c main.c),)
override TARGET = lfs
endif
TARGET = lfs
CC ?= gcc
AR ?= ar
SIZE ?= size
CC = gcc
AR = ar
SIZE = size
SRC += $(wildcard *.c emubd/*.c)
OBJ := $(SRC:.c=.o)
@@ -17,16 +14,15 @@ TEST := $(patsubst tests/%.sh,%,$(wildcard tests/test_*))
SHELL = /bin/bash -o pipefail
ifdef DEBUG
override CFLAGS += -O0 -g3
CFLAGS += -O0 -g3
else
override CFLAGS += -Os
CFLAGS += -Os
endif
ifdef WORD
override CFLAGS += -m$(WORD)
CFLAGS += -m$(WORD)
endif
override CFLAGS += -I.
override CFLAGS += -std=c99 -Wall -pedantic
override CFLAGS += -Wshadow -Wunused-parameter -Wjump-misses-init -Wsign-compare
CFLAGS += -I.
CFLAGS += -std=c99 -Wall -pedantic
all: $(TARGET)
@@ -37,20 +33,18 @@ size: $(OBJ)
$(SIZE) -t $^
.SUFFIXES:
test: test_format test_dirs test_files test_seek test_truncate \
test_interspersed test_alloc test_paths test_orphan test_move test_corrupt
@rm test.c
test: test_format test_dirs test_files test_seek test_truncate test_parallel \
test_alloc test_paths test_orphan test_move test_corrupt
test_%: tests/test_%.sh
ifdef QUIET
@./$< | sed -n '/^[-=]/p'
./$< | sed -n '/^[-=]/p'
else
./$<
endif
-include $(DEP)
lfs: $(OBJ)
$(TARGET): $(OBJ)
$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@
%.a: $(OBJ)

View File

@@ -16,7 +16,7 @@ of memory. Recursion is avoided and dynamic memory is limited to configurable
buffers that can be provided statically.
**Power-loss resilient** - The littlefs is designed for systems that may have
random power failures. The littlefs has strong copy-on-write guarantees and
random power failures. The littlefs has strong copy-on-write guaruntees and
storage on disk is always kept in a valid state.
**Wear leveling** - Since the most common form of embedded storage is erodible
@@ -88,7 +88,7 @@ int main(void) {
## Usage
Detailed documentation (or at least as much detail as is currently available)
can be found in the comments in [lfs.h](lfs.h).
can be cound in the comments in [lfs.h](lfs.h).
As you may have noticed, littlefs takes in a configuration structure that
defines how the filesystem operates. The configuration struct provides the
@@ -101,31 +101,24 @@ to the user to allocate, allowing multiple filesystems to be in use
simultaneously. With the `lfs_t` and configuration struct, a user can
format a block device or mount the filesystem.
Once mounted, the littlefs provides a full set of POSIX-like file and
Once mounted, the littlefs provides a full set of posix-like file and
directory functions, with the deviation that the allocation of filesystem
structures must be provided by the user.
All POSIX operations, such as remove and rename, are atomic, even in event
of power-loss. Additionally, no file updates are actually committed to the
All posix operations, such as remove and rename, are atomic, even in event
of power-loss. Additionally, no file updates are actually commited to the
filesystem until sync or close is called on the file.
## Other notes
All littlefs calls have the potential to return a negative error code. The
errors can be either one of those found in the `enum lfs_error` in
[lfs.h](lfs.h), or an error returned by the user's block device operations.
All littlefs have the potential to return a negative error code. The errors
can be either one of those found in the `enum lfs_error` in [lfs.h](lfs.h),
or an error returned by the user's block device operations.
In the configuration struct, the `prog` and `erase` function provided by the
user may return a `LFS_ERR_CORRUPT` error if the implementation already can
detect corrupt blocks. However, the wear leveling does not depend on the return
code of these functions, instead all data is read back and checked for
integrity.
If your storage caches writes, make sure that the provided `sync` function
flushes all the data to memory and ensures that the next read fetches the data
from memory, otherwise data integrity can not be guaranteed. If the `write`
function does not perform caching, and therefore each `read` or `write` call
hits the memory, the `sync` function can simply return 0.
It should also be noted that the current implementation of littlefs doesn't
really do anything to insure that the data written to disk is machine portable.
This is fine as long as all of the involved machines share endianness
(little-endian) and don't have strange padding requirements.
## Reference material
@@ -138,27 +131,14 @@ with all the nitty-gritty details. Can be useful for developing tooling.
## Testing
The littlefs comes with a test suite designed to run on a PC using the
The littlefs comes with a test suite designed to run on a pc using the
[emulated block device](emubd/lfs_emubd.h) found in the emubd directory.
The tests assume a Linux environment and can be started with make:
The tests assume a linux environment and can be started with make:
``` bash
make test
```
## License
The littlefs is provided under the [BSD-3-Clause](https://spdx.org/licenses/BSD-3-Clause.html)
license. See [LICENSE.md](LICENSE.md) for more information. Contributions to
this project are accepted under the same license.
Individual files contain the following tag instead of the full license text.
SPDX-License-Identifier: BSD-3-Clause
This enables machine processing of license information based on the SPDX
License Identifiers that are here available: http://spdx.org/licenses/
## Related projects
[Mbed OS](https://github.com/ARMmbed/mbed-os/tree/master/features/filesystem/littlefs) -
@@ -168,25 +148,10 @@ littlefs is available in Mbed OS as the [LittleFileSystem](https://os.mbed.com/d
class.
[littlefs-fuse](https://github.com/geky/littlefs-fuse) - A [FUSE](https://github.com/libfuse/libfuse)
wrapper for littlefs. The project allows you to mount littlefs directly on a
wrapper for littlefs. The project allows you to mount littlefs directly in a
Linux machine. Can be useful for debugging littlefs if you have an SD card
handy.
[littlefs-js](https://github.com/geky/littlefs-js) - A javascript wrapper for
littlefs. I'm not sure why you would want this, but it is handy for demos.
You can see it in action [here](http://littlefs.geky.net/demo.html).
[mklfs](https://github.com/whitecatboard/Lua-RTOS-ESP32/tree/master/components/mklfs/src) -
A command line tool built by the [Lua RTOS](https://github.com/whitecatboard/Lua-RTOS-ESP32)
guys for making littlefs images from a host PC. Supports Windows, Mac OS,
and Linux.
[SPIFFS](https://github.com/pellepl/spiffs) - Another excellent embedded
filesystem for NOR flash. As a more traditional logging filesystem with full
static wear-leveling, SPIFFS will likely outperform littlefs on small
memories such as the internal flash on microcontrollers.
[Dhara](https://github.com/dlbeer/dhara) - An interesting NAND flash
translation layer designed for small MCUs. It offers static wear-leveling and
power-resilience with only a fixed O(|address|) pointer structure stored on
each block and in RAM.

12
SPEC.md
View File

@@ -46,7 +46,7 @@ Here's the layout of metadata blocks on disk:
| 0x04 | 32 bits | dir size |
| 0x08 | 64 bits | tail pointer |
| 0x10 | size-16 bytes | dir entries |
| 0x00+s | 32 bits | CRC |
| 0x00+s | 32 bits | crc |
**Revision count** - Incremented every update, only the uncorrupted
metadata-block with the most recent revision count contains the valid metadata.
@@ -75,7 +75,7 @@ Here's an example of a simple directory stored on disk:
(32 bits) revision count = 10 (0x0000000a)
(32 bits) dir size = 154 bytes, end of dir (0x0000009a)
(64 bits) tail pointer = 37, 36 (0x00000025, 0x00000024)
(32 bits) CRC = 0xc86e3106
(32 bits) crc = 0xc86e3106
00000000: 0a 00 00 00 9a 00 00 00 25 00 00 00 24 00 00 00 ........%...$...
00000010: 22 08 00 03 05 00 00 00 04 00 00 00 74 65 61 22 "...........tea"
@@ -138,12 +138,12 @@ not include the entry type size, attributes, or name. The full size in bytes
of the entry is 4 + entry length + attribute length + name length.
**Attribute length** - Length of system-specific attributes in bytes. Since
attributes are system specific, there is not much guarantee on the values in
attributes are system specific, there is not much garuntee on the values in
this section, and systems are expected to work even when it is empty. See the
[attributes](#entry-attributes) section for more details.
**Name length** - Length of the entry name. Entry names are stored as UTF8,
although most systems will probably only support ASCII. Entry names can not
**Name length** - Length of the entry name. Entry names are stored as utf8,
although most systems will probably only support ascii. Entry names can not
contain '/' and can not be '.' or '..' as these are a part of the syntax of
filesystem paths.
@@ -222,7 +222,7 @@ Here's an example of a complete superblock:
(32 bits) block count = 1024 blocks (0x00000400)
(32 bits) version = 1.1 (0x00010001)
(8 bytes) magic string = littlefs
(32 bits) CRC = 0xc50b74fa
(32 bits) crc = 0xc50b74fa
00000000: 03 00 00 00 34 00 00 00 03 00 00 00 02 00 00 00 ....4...........
00000010: 2e 14 00 08 03 00 00 00 02 00 00 00 00 02 00 00 ................

View File

@@ -1,8 +1,19 @@
/*
* Block device emulated on standard files
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "emubd/lfs_emubd.h"
@@ -16,7 +27,6 @@
#include <unistd.h>
#include <assert.h>
#include <stdbool.h>
#include <inttypes.h>
// Block device emulated on existing filesystem
@@ -47,24 +57,19 @@ int lfs_emubd_create(const struct lfs_config *cfg, const char *path) {
// Load stats to continue incrementing
snprintf(emu->child, LFS_NAME_MAX, "stats");
FILE *f = fopen(emu->path, "r");
if (!f && errno != ENOENT) {
if (!f) {
return -errno;
}
if (errno == ENOENT) {
memset(&emu->stats, 0x0, sizeof(emu->stats));
} else {
size_t res = fread(&emu->stats, sizeof(emu->stats), 1, f);
if (res < 1) {
return -errno;
}
size_t res = fread(&emu->stats, sizeof(emu->stats), 1, f);
if (res < 1) {
return -errno;
}
err = fclose(f);
if (err) {
return -errno;
}
err = fclose(f);
if (err) {
return -errno;
}
return 0;
@@ -91,7 +96,7 @@ int lfs_emubd_read(const struct lfs_config *cfg, lfs_block_t block,
memset(data, 0, size);
// Read data
snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
snprintf(emu->child, LFS_NAME_MAX, "%x", block);
FILE *f = fopen(emu->path, "rb");
if (!f && errno != ENOENT) {
@@ -130,7 +135,7 @@ int lfs_emubd_prog(const struct lfs_config *cfg, lfs_block_t block,
assert(block < cfg->block_count);
// Program data
snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
snprintf(emu->child, LFS_NAME_MAX, "%x", block);
FILE *f = fopen(emu->path, "r+b");
if (!f) {
@@ -177,7 +182,7 @@ int lfs_emubd_erase(const struct lfs_config *cfg, lfs_block_t block) {
assert(block < cfg->block_count);
// Erase the block
snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
snprintf(emu->child, LFS_NAME_MAX, "%x", block);
struct stat st;
int err = stat(emu->path, &st);
if (err && errno != ENOENT) {
@@ -185,13 +190,13 @@ int lfs_emubd_erase(const struct lfs_config *cfg, lfs_block_t block) {
}
if (!err && S_ISREG(st.st_mode) && (S_IWUSR & st.st_mode)) {
err = unlink(emu->path);
int err = unlink(emu->path);
if (err) {
return -errno;
}
}
if (err || (S_ISREG(st.st_mode) && (S_IWUSR & st.st_mode))) {
if (errno == ENOENT || (S_ISREG(st.st_mode) && (S_IWUSR & st.st_mode))) {
FILE *f = fopen(emu->path, "w");
if (!f) {
return -errno;
@@ -245,3 +250,4 @@ int lfs_emubd_sync(const struct lfs_config *cfg) {
return 0;
}

View File

@@ -1,8 +1,19 @@
/*
* Block device emulated on standard files
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LFS_EMUBD_H
#define LFS_EMUBD_H
@@ -10,11 +21,6 @@
#include "lfs.h"
#include "lfs_util.h"
#ifdef __cplusplus
extern "C"
{
#endif
// Config options
#ifndef LFS_EMUBD_READ_SIZE
@@ -80,8 +86,4 @@ int lfs_emubd_erase(const struct lfs_config *cfg, lfs_block_t block);
int lfs_emubd_sync(const struct lfs_config *cfg);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif

822
lfs.c

File diff suppressed because it is too large Load Diff

90
lfs.h
View File

@@ -1,8 +1,19 @@
/*
* The little filesystem
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LFS_H
#define LFS_H
@@ -10,28 +21,6 @@
#include <stdint.h>
#include <stdbool.h>
#ifdef __cplusplus
extern "C"
{
#endif
/// Version info ///
// Software library version
// Major (top-nibble), incremented on backwards incompatible changes
// Minor (bottom-nibble), incremented on feature additions
#define LFS_VERSION 0x00010007
#define LFS_VERSION_MAJOR (0xffff & (LFS_VERSION >> 16))
#define LFS_VERSION_MINOR (0xffff & (LFS_VERSION >> 0))
// Version of On-disk data structures
// Major (top-nibble), incremented on backwards incompatible changes
// Minor (bottom-nibble), incremented on feature additions
#define LFS_DISK_VERSION 0x00010001
#define LFS_DISK_VERSION_MAJOR (0xffff & (LFS_DISK_VERSION >> 16))
#define LFS_DISK_VERSION_MINOR (0xffff & (LFS_DISK_VERSION >> 0))
/// Definitions ///
@@ -49,11 +38,6 @@ typedef uint32_t lfs_block_t;
#define LFS_NAME_MAX 255
#endif
// Max file size in bytes
#ifndef LFS_FILE_MAX
#define LFS_FILE_MAX 2147483647
#endif
// Possible error codes, these are negative to allow
// valid positive return values
enum lfs_error {
@@ -65,8 +49,6 @@ enum lfs_error {
LFS_ERR_NOTDIR = -20, // Entry is not a dir
LFS_ERR_ISDIR = -21, // Entry is a dir
LFS_ERR_NOTEMPTY = -39, // Dir is not empty
LFS_ERR_BADF = -9, // Bad file number
LFS_ERR_FBIG = -27, // File too large
LFS_ERR_INVAL = -22, // Invalid parameter
LFS_ERR_NOSPC = -28, // No space left on device
LFS_ERR_NOMEM = -12, // No more memory available
@@ -173,12 +155,6 @@ struct lfs_config {
void *file_buffer;
};
// Optional configuration provided during lfs_file_opencfg
struct lfs_file_config {
// Optional, statically allocated buffer for files. Must be program sized.
// If NULL, malloc will be used by default.
void *buffer;
};
// File info structure
struct lfs_info {
@@ -226,7 +202,6 @@ typedef struct lfs_file {
lfs_block_t head;
lfs_size_t size;
const struct lfs_file_config *cfg;
uint32_t flags;
lfs_off_t pos;
lfs_block_t block;
@@ -266,10 +241,9 @@ typedef struct lfs_superblock {
} lfs_superblock_t;
typedef struct lfs_free {
lfs_block_t begin;
lfs_block_t end;
lfs_block_t off;
lfs_block_t size;
lfs_block_t i;
lfs_block_t ack;
uint32_t *buffer;
} lfs_free_t;
@@ -286,7 +260,6 @@ typedef struct lfs {
lfs_free_t free;
bool deorphaned;
bool moving;
} lfs_t;
@@ -295,8 +268,7 @@ typedef struct lfs {
// Format a block device with the littlefs
//
// Requires a littlefs object and config struct. This clobbers the littlefs
// object, and does not leave the filesystem mounted. The config struct must
// be zeroed for defaults and backwards compatibility.
// object, and does not leave the filesystem mounted.
//
// Returns a negative error code on failure.
int lfs_format(lfs_t *lfs, const struct lfs_config *config);
@@ -305,8 +277,7 @@ int lfs_format(lfs_t *lfs, const struct lfs_config *config);
//
// Requires a littlefs object and config struct. Multiple filesystems
// may be mounted simultaneously with multiple littlefs objects. Both
// lfs and config must be allocated while mounted. The config struct must
// be zeroed for defaults and backwards compatibility.
// lfs and config must be allocated while mounted.
//
// Returns a negative error code on failure.
int lfs_mount(lfs_t *lfs, const struct lfs_config *config);
@@ -330,6 +301,10 @@ int lfs_remove(lfs_t *lfs, const char *path);
// If the destination exists, it must match the source in type.
// If the destination is a directory, the directory must be empty.
//
// Note: If power loss occurs, it is possible that the file or directory
// will exist in both the oldpath and newpath simultaneously after the
// next mount.
//
// Returns a negative error code on failure.
int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath);
@@ -344,27 +319,14 @@ int lfs_stat(lfs_t *lfs, const char *path, struct lfs_info *info);
// Open a file
//
// The mode that the file is opened in is determined by the flags, which
// are values from the enum lfs_open_flags that are bitwise-ored together.
// The mode that the file is opened in is determined
// by the flags, which are values from the enum lfs_open_flags
// that are bitwise-ored together.
//
// Returns a negative error code on failure.
int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
const char *path, int flags);
// Open a file with extra configuration
//
// The mode that the file is opened in is determined by the flags, which
// are values from the enum lfs_open_flags that are bitwise-ored together.
//
// The config struct provides additional config options per file as described
// above. The config struct must be allocated while the file is open, and the
// config struct must be zeroed for defaults and backwards compatibility.
//
// Returns a negative error code on failure.
int lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file,
const char *path, int flags,
const struct lfs_file_config *config);
// Close a file
//
// Any pending writes are written out to storage as though
@@ -494,8 +456,4 @@ int lfs_traverse(lfs_t *lfs, int (*cb)(void*, lfs_block_t), void *data);
int lfs_deorphan(lfs_t *lfs);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif

View File

@@ -1,16 +1,23 @@
/*
* lfs util functions
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "lfs_util.h"
// Only compile if user does not provide custom config
#ifndef LFS_CONFIG
// Software CRC implementation with small lookup table
void lfs_crc(uint32_t *restrict crc, const void *buffer, size_t size) {
static const uint32_t rtable[16] = {
0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
@@ -27,5 +34,3 @@ void lfs_crc(uint32_t *restrict crc, const void *buffer, size_t size) {
}
}
#endif

View File

@@ -1,84 +1,30 @@
/*
* lfs utility functions
*
* Copyright (c) 2017, Arm Limited. All rights reserved.
* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LFS_UTIL_H
#define LFS_UTIL_H
// Users can override lfs_util.h with their own configuration by defining
// LFS_CONFIG as a header file to include (-DLFS_CONFIG=lfs_config.h).
//
// If LFS_CONFIG is used, none of the default utils will be emitted and must be
// provided by the config file. To start I would suggest copying lfs_util.h and
// modifying as needed.
#ifdef LFS_CONFIG
#define LFS_STRINGIZE(x) LFS_STRINGIZE2(x)
#define LFS_STRINGIZE2(x) #x
#include LFS_STRINGIZE(LFS_CONFIG)
#else
// System includes
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#ifndef LFS_NO_MALLOC
#include <stdlib.h>
#endif
#ifndef LFS_NO_ASSERT
#include <assert.h>
#endif
#if !defined(LFS_NO_DEBUG) || !defined(LFS_NO_WARN) || !defined(LFS_NO_ERROR)
#include <stdint.h>
#include <stdio.h>
#endif
#ifdef __cplusplus
extern "C"
{
#endif
// Macros, may be replaced by system specific wrappers. Arguments to these
// macros must not have side-effects as the macros can be removed for a smaller
// code footprint
// Logging functions
#ifndef LFS_NO_DEBUG
#define LFS_DEBUG(fmt, ...) \
printf("lfs debug:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_DEBUG(fmt, ...)
#endif
#ifndef LFS_NO_WARN
#define LFS_WARN(fmt, ...) \
printf("lfs warn:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_WARN(fmt, ...)
#endif
#ifndef LFS_NO_ERROR
#define LFS_ERROR(fmt, ...) \
printf("lfs error:%d: " fmt "\n", __LINE__, __VA_ARGS__)
#else
#define LFS_ERROR(fmt, ...)
#endif
// Runtime assertions
#ifndef LFS_NO_ASSERT
#define LFS_ASSERT(test) assert(test)
#else
#define LFS_ASSERT(test)
#endif
// Builtin functions, these may be replaced by more efficient
// toolchain-specific implementations. LFS_NO_INTRINSICS falls back to a more
// expensive basic C implementation for debugging purposes
// Min/max functions for unsigned 32-bit numbers
// Builtin functions, these may be replaced by more
// efficient implementations in the system
static inline uint32_t lfs_max(uint32_t a, uint32_t b) {
return (a > b) ? a : b;
}
@@ -87,60 +33,26 @@ static inline uint32_t lfs_min(uint32_t a, uint32_t b) {
return (a < b) ? a : b;
}
// Find the next smallest power of 2 less than or equal to a
static inline uint32_t lfs_npw2(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
return 32 - __builtin_clz(a-1);
#else
uint32_t r = 0;
uint32_t s;
a -= 1;
s = (a > 0xffff) << 4; a >>= s; r |= s;
s = (a > 0xff ) << 3; a >>= s; r |= s;
s = (a > 0xf ) << 2; a >>= s; r |= s;
s = (a > 0x3 ) << 1; a >>= s; r |= s;
return (r | (a >> 1)) + 1;
#endif
}
// Count the number of trailing binary zeros in a
// lfs_ctz(0) may be undefined
static inline uint32_t lfs_ctz(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && defined(__GNUC__)
return __builtin_ctz(a);
#else
return lfs_npw2((a & -a) + 1) - 1;
#endif
}
// Count the number of binary ones in a
static inline uint32_t lfs_npw2(uint32_t a) {
return 32 - __builtin_clz(a-1);
}
static inline uint32_t lfs_popc(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && (defined(__GNUC__) || defined(__CC_ARM))
return __builtin_popcount(a);
#else
a = a - ((a >> 1) & 0x55555555);
a = (a & 0x33333333) + ((a >> 2) & 0x33333333);
return (((a + (a >> 4)) & 0xf0f0f0f) * 0x1010101) >> 24;
#endif
}
// Find the sequence comparison of a and b, this is the distance
// between a and b ignoring overflow
static inline int lfs_scmp(uint32_t a, uint32_t b) {
return (int)(unsigned)(a - b);
}
// Convert from 32-bit little-endian to native order
static inline uint32_t lfs_fromle32(uint32_t a) {
#if !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && BYTE_ORDER == ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER ) && __BYTE_ORDER == __ORDER_LITTLE_ENDIAN ) || \
(defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__))
#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return a;
#elif !defined(LFS_NO_INTRINSICS) && ( \
(defined( BYTE_ORDER ) && BYTE_ORDER == ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER ) && __BYTE_ORDER == __ORDER_BIG_ENDIAN ) || \
(defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__))
#elif defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
return __builtin_bswap32(a);
#else
return (((uint8_t*)&a)[0] << 0) |
@@ -150,37 +62,19 @@ static inline uint32_t lfs_fromle32(uint32_t a) {
#endif
}
// Convert to 32-bit little-endian from native order
static inline uint32_t lfs_tole32(uint32_t a) {
return lfs_fromle32(a);
}
// Calculate CRC-32 with polynomial = 0x04c11db7
// CRC-32 with polynomial = 0x04c11db7
void lfs_crc(uint32_t *crc, const void *buffer, size_t size);
// Allocate memory, only used if buffers are not provided to littlefs
static inline void *lfs_malloc(size_t size) {
#ifndef LFS_NO_MALLOC
return malloc(size);
#else
(void)size;
return NULL;
#endif
}
// Deallocate memory, only used if buffers are not provided to littlefs
static inline void lfs_free(void *p) {
#ifndef LFS_NO_MALLOC
free(p);
#else
(void)p;
#endif
}
// Logging functions, these may be replaced by system-specific
// logging functions
#define LFS_DEBUG(fmt, ...) printf("lfs debug: " fmt "\n", __VA_ARGS__)
#define LFS_WARN(fmt, ...) printf("lfs warn: " fmt "\n", __VA_ARGS__)
#define LFS_ERROR(fmt, ...) printf("lfs error: " fmt "\n", __VA_ARGS__)
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif
#endif

View File

@@ -7,11 +7,11 @@
// test stuff
static void test_log(const char *s, uintmax_t v) {{
void test_log(const char *s, uintmax_t v) {{
printf("%s: %jd\n", s, v);
}}
static void test_assert(const char *file, unsigned line,
void test_assert(const char *file, unsigned line,
const char *s, uintmax_t v, uintmax_t e) {{
static const char *last[6] = {{0, 0}};
if (v != e || !(last[0] == s || last[1] == s ||
@@ -37,8 +37,7 @@ static void test_assert(const char *file, unsigned line,
// utility functions for traversals
static int __attribute__((used)) test_count(void *p, lfs_block_t b) {{
(void)b;
int test_count(void *p, lfs_block_t b) {{
unsigned *u = (unsigned*)p;
*u += 1;
return 0;
@@ -59,7 +58,7 @@ lfs_size_t size;
lfs_size_t wsize;
lfs_size_t rsize;
uintmax_t test;
uintmax_t res;
#ifndef LFS_READ_SIZE
#define LFS_READ_SIZE 16
@@ -97,7 +96,7 @@ const struct lfs_config cfg = {{
// Entry point
int main(void) {{
int main() {{
lfs_emubd_create(&cfg, "blocks");
{tests}

View File

@@ -14,34 +14,22 @@ def generate(test):
match = re.match('(?: *\n)*( *)(.*)=>(.*);', line, re.DOTALL | re.MULTILINE)
if match:
tab, test, expect = match.groups()
lines.append(tab+'test = {test};'.format(test=test.strip()))
lines.append(tab+'test_assert("{name}", test, {expect});'.format(
lines.append(tab+'res = {test};'.format(test=test.strip()))
lines.append(tab+'test_assert("{name}", res, {expect});'.format(
name = re.match('\w*', test.strip()).group(),
expect = expect.strip()))
else:
lines.append(line)
# Create test file
with open('test.c', 'w') as file:
file.write(template.format(tests='\n'.join(lines)))
# Remove build artifacts to force rebuild
try:
os.remove('test.o')
os.remove('lfs')
except OSError:
pass
def compile():
subprocess.check_call([
os.environ.get('MAKE', 'make'),
'--no-print-directory', '-s'])
os.environ['CFLAGS'] = os.environ.get('CFLAGS', '') + ' -Werror'
subprocess.check_call(['make', '--no-print-directory', '-s'], env=os.environ)
def execute():
if 'EXEC' in os.environ:
subprocess.check_call([os.environ['EXEC'], "./lfs"])
else:
subprocess.check_call(["./lfs"])
subprocess.check_call(["./lfs"])
def main(test=None):
if test and not test.startswith('-'):

View File

@@ -32,18 +32,18 @@ lfs_alloc_singleproc() {
tests/test.py << TEST
const char *names[] = {"bacon", "eggs", "pancakes"};
lfs_mount(&lfs, &cfg) => 0;
for (unsigned n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
for (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
sprintf((char*)buffer, "$1/%s", names[n]);
lfs_file_open(&lfs, &file[n], (char*)buffer,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
}
for (unsigned n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
for (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
size = strlen(names[n]);
for (int i = 0; i < $SIZE; i++) {
lfs_file_write(&lfs, &file[n], names[n], size) => size;
}
}
for (unsigned n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
for (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
lfs_file_close(&lfs, &file[n]) => 0;
}
lfs_unmount(&lfs) => 0;
@@ -266,163 +266,6 @@ tests/test.py << TEST
lfs_mkdir(&lfs, "exhaustiondir2") => LFS_ERR_NOSPC;
TEST
echo "--- Split dir test ---"
rm -rf blocks
tests/test.py << TEST
lfs_format(&lfs, &cfg) => 0;
TEST
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
// create one block whole for half a directory
lfs_file_open(&lfs, &file[0], "bump", LFS_O_WRONLY | LFS_O_CREAT) => 0;
lfs_file_write(&lfs, &file[0], (void*)"hi", 2) => 2;
lfs_file_close(&lfs, &file[0]) => 0;
lfs_file_open(&lfs, &file[0], "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < (cfg.block_count-6)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
// open hole
lfs_remove(&lfs, "bump") => 0;
lfs_mkdir(&lfs, "splitdir") => 0;
lfs_file_open(&lfs, &file[0], "splitdir/bump",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
lfs_file_write(&lfs, &file[0], buffer, size) => LFS_ERR_NOSPC;
lfs_file_close(&lfs, &file[0]) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Outdated lookahead test ---"
rm -rf blocks
tests/test.py << TEST
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// fill completely with two files
lfs_file_open(&lfs, &file[0], "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-4)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
lfs_file_open(&lfs, &file[0], "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-4+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
// remount to force reset of lookahead
lfs_unmount(&lfs) => 0;
lfs_mount(&lfs, &cfg) => 0;
// rewrite one file
lfs_file_open(&lfs, &file[0], "exhaustion1",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file[0]) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-4)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
// rewrite second file, this requires lookahead does not
// use old population
lfs_file_open(&lfs, &file[0], "exhaustion2",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file[0]) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-4+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
TEST
echo "--- Outdated lookahead and split dir test ---"
rm -rf blocks
tests/test.py << TEST
lfs_format(&lfs, &cfg) => 0;
lfs_mount(&lfs, &cfg) => 0;
// fill completely with two files
lfs_file_open(&lfs, &file[0], "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-4)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
lfs_file_open(&lfs, &file[0], "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-4+1)/2)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 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[0], "exhaustion1",
LFS_O_WRONLY | LFS_O_TRUNC) => 0;
lfs_file_sync(&lfs, &file[0]) => 0;
size = strlen("blahblahblahblah");
memcpy(buffer, "blahblahblahblah", size);
for (lfs_size_t i = 0;
i < ((cfg.block_count-4)/2 - 1)*(cfg.block_size-8);
i += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_close(&lfs, &file[0]) => 0;
// try to allocate a directory, should fail!
lfs_mkdir(&lfs, "split") => LFS_ERR_NOSPC;
// file should not fail
lfs_file_open(&lfs, &file[0], "notasplit",
LFS_O_WRONLY | LFS_O_CREAT) => 0;
lfs_file_write(&lfs, &file[0], "hi", 2) => 2;
lfs_file_close(&lfs, &file[0]) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Results ---"
tests/stats.py

View File

@@ -118,7 +118,6 @@ tests/test.py << TEST
sprintf((char*)buffer, "test%d", i);
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, (char*)buffer) => 0;
info.type => LFS_TYPE_DIR;
}
lfs_dir_read(&lfs, &dir[0], &info) => 0;
lfs_unmount(&lfs) => 0;
@@ -221,7 +220,7 @@ tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "warmpotato") => 0;
lfs_mkdir(&lfs, "warmpotato/mushy") => 0;
lfs_rename(&lfs, "hotpotato", "warmpotato") => LFS_ERR_NOTEMPTY;
lfs_rename(&lfs, "hotpotato", "warmpotato") => LFS_ERR_INVAL;
lfs_remove(&lfs, "warmpotato/mushy") => 0;
lfs_rename(&lfs, "hotpotato", "warmpotato") => 0;
@@ -326,42 +325,13 @@ tests/test.py << TEST
lfs_unmount(&lfs) => 0;
TEST
echo "--- Multi-block rename ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "cactus/test%d", i);
sprintf((char*)wbuffer, "cactus/tedd%d", i);
lfs_rename(&lfs, (char*)buffer, (char*)wbuffer) => 0;
}
lfs_unmount(&lfs) => 0;
TEST
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_dir_open(&lfs, &dir[0], "cactus") => 0;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, ".") => 0;
info.type => LFS_TYPE_DIR;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, "..") => 0;
info.type => LFS_TYPE_DIR;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "tedd%d", i);
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, (char*)buffer) => 0;
info.type => LFS_TYPE_DIR;
}
lfs_dir_read(&lfs, &dir[0], &info) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Multi-block remove ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_remove(&lfs, "cactus") => LFS_ERR_NOTEMPTY;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "cactus/tedd%d", i);
sprintf((char*)buffer, "cactus/test%d", i);
lfs_remove(&lfs, (char*)buffer) => 0;
}
@@ -385,100 +355,5 @@ tests/test.py << TEST
lfs_unmount(&lfs) => 0;
TEST
echo "--- Multi-block directory with files ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "prickly-pear") => 0;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "prickly-pear/test%d", i);
lfs_file_open(&lfs, &file[0], (char*)buffer,
LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = 6;
memcpy(wbuffer, "Hello", size);
lfs_file_write(&lfs, &file[0], wbuffer, size) => size;
lfs_file_close(&lfs, &file[0]) => 0;
}
lfs_unmount(&lfs) => 0;
TEST
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_dir_open(&lfs, &dir[0], "prickly-pear") => 0;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, ".") => 0;
info.type => LFS_TYPE_DIR;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, "..") => 0;
info.type => LFS_TYPE_DIR;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "test%d", i);
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, (char*)buffer) => 0;
info.type => LFS_TYPE_REG;
info.size => 6;
}
lfs_dir_read(&lfs, &dir[0], &info) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Multi-block rename with files ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "prickly-pear/test%d", i);
sprintf((char*)wbuffer, "prickly-pear/tedd%d", i);
lfs_rename(&lfs, (char*)buffer, (char*)wbuffer) => 0;
}
lfs_unmount(&lfs) => 0;
TEST
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_dir_open(&lfs, &dir[0], "prickly-pear") => 0;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, ".") => 0;
info.type => LFS_TYPE_DIR;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, "..") => 0;
info.type => LFS_TYPE_DIR;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "tedd%d", i);
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, (char*)buffer) => 0;
info.type => LFS_TYPE_REG;
info.size => 6;
}
lfs_dir_read(&lfs, &dir[0], &info) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Multi-block remove with files ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_remove(&lfs, "prickly-pear") => LFS_ERR_NOTEMPTY;
for (int i = 0; i < $LARGESIZE; i++) {
sprintf((char*)buffer, "prickly-pear/tedd%d", i);
lfs_remove(&lfs, (char*)buffer) => 0;
}
lfs_remove(&lfs, "prickly-pear") => 0;
lfs_unmount(&lfs) => 0;
TEST
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_dir_open(&lfs, &dir[0], "/") => 0;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, ".") => 0;
info.type => LFS_TYPE_DIR;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, "..") => 0;
info.type => LFS_TYPE_DIR;
lfs_dir_read(&lfs, &dir[0], &info) => 1;
strcmp(info.name, "burito") => 0;
info.type => LFS_TYPE_REG;
lfs_dir_read(&lfs, &dir[0], &info) => 0;
lfs_dir_close(&lfs, &dir[0]) => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Results ---"
tests/stats.py

View File

@@ -30,7 +30,7 @@ TEST
w_test() {
tests/test.py << TEST
size = $1;
lfs_size_t size = $1;
lfs_size_t chunk = 31;
srand(0);
lfs_mount(&lfs, &cfg) => 0;
@@ -50,7 +50,7 @@ TEST
r_test() {
tests/test.py << TEST
size = $1;
lfs_size_t size = $1;
lfs_size_t chunk = 29;
srand(0);
lfs_mount(&lfs, &cfg) => 0;
@@ -135,24 +135,5 @@ tests/test.py << TEST
lfs_unmount(&lfs) => 0;
TEST
echo "--- Many file test ---"
tests/test.py << TEST
lfs_format(&lfs, &cfg) => 0;
TEST
tests/test.py << TEST
// Create 300 files of 6 bytes
lfs_mount(&lfs, &cfg) => 0;
lfs_mkdir(&lfs, "directory") => 0;
for (unsigned i = 0; i < 300; i++) {
snprintf((char*)buffer, sizeof(buffer), "file_%03d", i);
lfs_file_open(&lfs, &file[0], (char*)buffer, LFS_O_WRONLY | LFS_O_CREAT) => 0;
size = 6;
memcpy(wbuffer, "Hello", size);
lfs_file_write(&lfs, &file[0], wbuffer, size) => size;
lfs_file_close(&lfs, &file[0]) => 0;
}
lfs_unmount(&lfs) => 0;
TEST
echo "--- Results ---"
tests/stats.py

View File

@@ -1,13 +1,13 @@
#!/bin/bash
set -eu
echo "=== Interspersed tests ==="
echo "=== Parallel tests ==="
rm -rf blocks
tests/test.py << TEST
lfs_format(&lfs, &cfg) => 0;
TEST
echo "--- Interspersed file test ---"
echo "--- Parallel file test ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file[0], "a", LFS_O_WRONLY | LFS_O_CREAT) => 0;
@@ -77,7 +77,7 @@ tests/test.py << TEST
lfs_unmount(&lfs) => 0;
TEST
echo "--- Interspersed remove file test ---"
echo "--- Parallel remove file test ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_file_open(&lfs, &file[0], "e", LFS_O_WRONLY | LFS_O_CREAT) => 0;

View File

@@ -90,22 +90,6 @@ tests/test.py << TEST
lfs_unmount(&lfs) => 0;
TEST
echo "--- Trailing dot path tests ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
lfs_stat(&lfs, "tea/hottea/", &info) => 0;
strcmp(info.name, "hottea") => 0;
lfs_stat(&lfs, "tea/hottea/.", &info) => 0;
strcmp(info.name, "hottea") => 0;
lfs_stat(&lfs, "tea/hottea/./.", &info) => 0;
strcmp(info.name, "hottea") => 0;
lfs_stat(&lfs, "tea/hottea/..", &info) => 0;
strcmp(info.name, "tea") => 0;
lfs_stat(&lfs, "tea/hottea/../.", &info) => 0;
strcmp(info.name, "tea") => 0;
lfs_unmount(&lfs) => 0;
TEST
echo "--- Root dot dot path tests ---"
tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
@@ -124,10 +108,6 @@ tests/test.py << TEST
lfs_stat(&lfs, "/", &info) => 0;
info.type => LFS_TYPE_DIR;
strcmp(info.name, "/") => 0;
lfs_mkdir(&lfs, "/") => LFS_ERR_EXIST;
lfs_file_open(&lfs, &file[0], "/", LFS_O_WRONLY | LFS_O_CREAT)
=> LFS_ERR_ISDIR;
lfs_unmount(&lfs) => 0;
TEST

View File

@@ -153,7 +153,7 @@ tests/test.py << TEST
lfs_file_read(&lfs, &file[0], buffer, size) => size;
memcmp(buffer, "kittycatcat", size) => 0;
size = lfs_file_size(&lfs, &file[0]);
lfs_size_t size = lfs_file_size(&lfs, &file[0]);
lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
lfs_file_close(&lfs, &file[0]) => 0;
@@ -202,7 +202,7 @@ tests/test.py << TEST
lfs_file_read(&lfs, &file[0], buffer, size) => size;
memcmp(buffer, "kittycatcat", size) => 0;
size = lfs_file_size(&lfs, &file[0]);
lfs_size_t size = lfs_file_size(&lfs, &file[0]);
lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
lfs_file_close(&lfs, &file[0]) => 0;
@@ -243,7 +243,7 @@ tests/test.py << TEST
lfs_file_read(&lfs, &file[0], buffer, size) => size;
memcmp(buffer, "kittycatcat", size) => 0;
size = lfs_file_size(&lfs, &file[0]);
lfs_size_t size = lfs_file_size(&lfs, &file[0]);
lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
lfs_file_close(&lfs, &file[0]) => 0;
@@ -286,7 +286,7 @@ tests/test.py << TEST
lfs_file_read(&lfs, &file[0], buffer, size) => size;
memcmp(buffer, "kittycatcat", size) => 0;
size = lfs_file_size(&lfs, &file[0]);
lfs_size_t size = lfs_file_size(&lfs, &file[0]);
lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
lfs_file_close(&lfs, &file[0]) => 0;
@@ -301,7 +301,7 @@ tests/test.py << TEST
size = strlen("hedgehoghog");
const lfs_soff_t offsets[] = {512, 1020, 513, 1021, 511, 1019};
for (unsigned i = 0; i < sizeof(offsets) / sizeof(offsets[0]); i++) {
for (int i = 0; i < sizeof(offsets) / sizeof(offsets[0]); i++) {
lfs_soff_t off = offsets[i];
memcpy(buffer, "hedgehoghog", size);
lfs_file_seek(&lfs, &file[0], off, LFS_SEEK_SET) => off;

View File

@@ -13,33 +13,26 @@ TEST
truncate_test() {
STARTSIZES="$1"
STARTSEEKS="$2"
HOTSIZES="$3"
COLDSIZES="$4"
HOTSIZES="$2"
COLDSIZES="$3"
tests/test.py << TEST
static const lfs_off_t startsizes[] = {$STARTSIZES};
static const lfs_off_t startseeks[] = {$STARTSEEKS};
static const lfs_off_t hotsizes[] = {$HOTSIZES};
lfs_mount(&lfs, &cfg) => 0;
for (unsigned i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
sprintf((char*)buffer, "hairyhead%d", i);
lfs_file_open(&lfs, &file[0], (const char*)buffer,
LFS_O_WRONLY | LFS_O_CREAT | LFS_O_TRUNC) => 0;
strcpy((char*)buffer, "hair");
size = strlen((char*)buffer);
for (lfs_off_t j = 0; j < startsizes[i]; j += size) {
for (int j = 0; j < startsizes[i]; j += size) {
lfs_file_write(&lfs, &file[0], buffer, size) => size;
}
lfs_file_size(&lfs, &file[0]) => startsizes[i];
if (startseeks[i] != startsizes[i]) {
lfs_file_seek(&lfs, &file[0],
startseeks[i], LFS_SEEK_SET) => startseeks[i];
}
lfs_file_truncate(&lfs, &file[0], hotsizes[i]) => 0;
lfs_file_size(&lfs, &file[0]) => hotsizes[i];
@@ -55,13 +48,13 @@ tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
for (unsigned i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
sprintf((char*)buffer, "hairyhead%d", i);
lfs_file_open(&lfs, &file[0], (const char*)buffer, LFS_O_RDWR) => 0;
lfs_file_size(&lfs, &file[0]) => hotsizes[i];
size = strlen("hair");
lfs_off_t j = 0;
int j = 0;
for (; j < startsizes[i] && j < hotsizes[i]; j += size) {
lfs_file_read(&lfs, &file[0], buffer, size) => size;
memcmp(buffer, "hair", size) => 0;
@@ -87,13 +80,13 @@ tests/test.py << TEST
lfs_mount(&lfs, &cfg) => 0;
for (unsigned i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
sprintf((char*)buffer, "hairyhead%d", i);
lfs_file_open(&lfs, &file[0], (const char*)buffer, LFS_O_RDONLY) => 0;
lfs_file_size(&lfs, &file[0]) => coldsizes[i];
size = strlen("hair");
lfs_off_t j = 0;
int j = 0;
for (; j < startsizes[i] && j < hotsizes[i] && j < coldsizes[i];
j += size) {
lfs_file_read(&lfs, &file[0], buffer, size) => size;
@@ -114,21 +107,18 @@ TEST
echo "--- Cold shrinking truncate ---"
truncate_test \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE"
echo "--- Cold expanding truncate ---"
truncate_test \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE"
echo "--- Warm shrinking truncate ---"
truncate_test \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, 0, 0, 0, 0"
@@ -136,21 +126,6 @@ truncate_test \
echo "--- Warm expanding truncate ---"
truncate_test \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE"
echo "--- Mid-file shrinking truncate ---"
truncate_test \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
" $LARGESIZE, $LARGESIZE, $LARGESIZE, $LARGESIZE, $LARGESIZE" \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, 0, 0, 0, 0"
echo "--- Mid-file expanding truncate ---"
truncate_test \
" 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE, 2*$LARGESIZE" \
" 0, 0, $SMALLSIZE, $MEDIUMSIZE, $LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE" \
"2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE, 2*$LARGESIZE"