Changed release script to generate drafts

Interesting open-source projects that I've ran into around embedded
storage. May be interesting to others in the embedded space.

Added mklfs, SPIFFS, and Dhara.

Also a thanks to jolivepetrus for posting the mklfs tool he put
together.

.travis.yml

@@ -27,7 +27,7 @@ script:
   # compile and find the code size with the smallest configuration
   - make clean size
         OBJ="$(ls lfs*.o | tr '\n' ' ')"
-        CFLAGS+="-DLFS_NO{ASSERT,DEBUG,WARN,ERROR}"
+        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
@@ -134,53 +134,58 @@ jobs:
         - STAGE=deploy
         - NAME=deploy
       script:
-        # Update tag for version defined in lfs.h
+        # 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 & ($LFS_VERSION >>  0)))
-        - LFS_VERSION="v$LFS_VERSION_MAJOR.$LFS_VERSION_MINOR"
+        # Grab latests patch from repo tags, default to 0, needs finagling to get past github's pagination api
-        - echo "littlefs version $LFS_VERSION"
+        - PREV_URL=https://api.github.com/repos/$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"
         - |
-          curl -u $GEKY_BOT_RELEASES -X POST \
+          # Check that we're the most recent commit
-            https://api.github.com/repos/$TRAVIS_REPO_SLUG/git/refs \
+          CURRENT_COMMIT=$(curl -f -u "$GEKY_BOT_RELEASES" \
-            -d "{
+                https://api.github.com/repos/$TRAVIS_REPO_SLUG/commits/master \
-              \"ref\": \"refs/tags/$LFS_VERSION\",
+                | jq -re '.sha')
-              \"sha\": \"$TRAVIS_COMMIT\"
+          if [ "$TRAVIS_COMMIT" == "$CURRENT_COMMIT" ]
-            }"
-        - |
-          curl -f -u $GEKY_BOT_RELEASES -X PATCH \
-            https://api.github.com/repos/$TRAVIS_REPO_SLUG/git/refs/tags/$LFS_VERSION \
-            -d "{
-              \"sha\": \"$TRAVIS_COMMIT\"
-            }"
-        # Create release notes from commits
-        - LFS_PREV_VERSION="v$LFS_VERSION_MAJOR.$(($LFS_VERSION_MINOR-1))"
-        - |
-          if [ $(git tag -l "$LFS_PREV_VERSION") ]
           then
-            curl -u $GEKY_BOT_RELEASES -X POST \
+            # Create a simple tag
-                https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases \
+            curl -f -u "$GEKY_BOT_RELEASES" -X POST \
+                https://api.github.com/repos/$TRAVIS_REPO_SLUG/git/refs \
                 -d "{
-                    \"tag_name\": \"$LFS_VERSION\",
+                    \"ref\": \"refs/tags/$LFS_VERSION\",
-                    \"name\": \"$LFS_VERSION\"
+                    \"sha\": \"$TRAVIS_COMMIT\"
                 }"
-            RELEASE=$(
+            # Minor release?
-                curl -f -u $GEKY_BOT_RELEASES \
+            if [[ "$LFS_VERSION" == *.0 ]]
-                    https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases/tags/$LFS_VERSION
+            then
-            )
+              # Build release notes
-            CHANGES=$(
+              PREV=$(git tag --sort=-v:refname -l "v*.0" | head -1)
-                git log --oneline $LFS_PREV_VERSION.. --grep='^Merge' --invert-grep
+              if [ ! -z "$PREV" ]
-            )
+              then
-            curl -f -u $GEKY_BOT_RELEASES -X PATCH \
+                  echo "PREV $PREV"
-                https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases/$(
+                  CHANGES=$'### Changes\n\n'$( \
-                    jq -r '.id' <<< "$RELEASE"
+                      git log --oneline $PREV.. --grep='^Merge' --invert-grep)
-                ) \
+                  printf "CHANGES\n%s\n\n" "$CHANGES"
-                -d "$(
+              fi
-                    jq -s '{
+              # Create the release
-                        "body": ((.[0] // "" | sub("(?<=\n)#+ Changes.*"; ""; "mi"))
+              curl -f -u "$GEKY_BOT_RELEASES" -X POST \
-                            + "### Changes\n\n" + .[1])
+                  https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases \
-                    }' <(jq '.body' <<< "$RELEASE") <(jq -sR '.' <<< "$CHANGES")
+                  -d "{
-                )"
+                      \"tag_name\": \"$LFS_VERSION\",
+                      \"name\": \"${LFS_VERSION%.0}\",
+                      \"draft\": true,
+                      \"body\": $(jq -sR '.' <<< "$CHANGES")
+                  }"
+            fi
           fi
 
 # Manage statuses

LICENSE.md

@@ -22,15 +22,3 @@ LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
----
-
-*Note*:
-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/

Makefile

@@ -1,4 +1,7 @@
-TARGET = lfs
+TARGET = lfs.a
+ifneq ($(wildcard test.c main.c),)
+override TARGET = lfs
+endif
 
 CC ?= gcc
 AR ?= ar
@@ -23,6 +26,7 @@ override CFLAGS += -m$(WORD)
 endif
 override CFLAGS += -I.
 override CFLAGS += -std=c99 -Wall -pedantic
+override CFLAGS += -Wshadow -Wunused-parameter -Wjump-misses-init -Wsign-compare
 
 
 all: $(TARGET)
@@ -35,7 +39,9 @@ size: $(OBJ)
 .SUFFIXES:
 test: test_format test_dirs test_files test_seek test_truncate \
 	test_interspersed test_alloc test_paths test_orphan test_move test_corrupt
+	@rm test.c
 test_%: tests/test_%.sh
+
 ifdef QUIET
 	@./$< | sed -n '/^[-=]/p'
 else
@@ -44,7 +50,7 @@ endif
 
 -include $(DEP)
 
-$(TARGET): $(OBJ)
+lfs: $(OBJ)
 	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@
 
 %.a: $(OBJ)

README.md

@@ -146,6 +146,19 @@ The tests assume a Linux environment and can be started with make:
 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) -
@@ -162,3 +175,18 @@ 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.

emubd/lfs_emubd.c

@@ -16,6 +16,7 @@
 #include <unistd.h>
 #include <assert.h>
 #include <stdbool.h>
+#include <inttypes.h>
 
 
 // Block device emulated on existing filesystem
@@ -46,19 +47,24 @@ 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) {
+    if (!f && errno != ENOENT) {
         return -errno;
     }
 
-    size_t res = fread(&emu->stats, sizeof(emu->stats), 1, f);
+    if (errno == ENOENT) {
-    if (res < 1) {
+        memset(&emu->stats, 0x0, sizeof(emu->stats));
-        return -errno;
+    } else {
-    }
+        size_t res = fread(&emu->stats, sizeof(emu->stats), 1, f);
+        if (res < 1) {
+            return -errno;
+        }
 
-    err = fclose(f);
+        err = fclose(f);
-    if (err) {
+        if (err) {
-        return -errno;
+            return -errno;
+        }
     }
 
     return 0;
@@ -85,7 +91,7 @@ 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, "%x", block);
+    snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
 
     FILE *f = fopen(emu->path, "rb");
     if (!f && errno != ENOENT) {
@@ -124,7 +130,7 @@ 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, "%x", block);
+    snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
 
     FILE *f = fopen(emu->path, "r+b");
     if (!f) {
@@ -171,7 +177,7 @@ 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, "%x", block);
+    snprintf(emu->child, LFS_NAME_MAX, "%" PRIx32, block);
     struct stat st;
     int err = stat(emu->path, &st);
     if (err && errno != ENOENT) {
@@ -239,4 +245,3 @@ int lfs_emubd_sync(const struct lfs_config *cfg) {
 
     return 0;
 }
-

emubd/lfs_emubd.h

@@ -10,6 +10,11 @@
 #include "lfs.h"
 #include "lfs_util.h"
 
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 
 // Config options
 #ifndef LFS_EMUBD_READ_SIZE
@@ -75,4 +80,8 @@ 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

lfs.c

@@ -7,6 +7,8 @@
 #include "lfs.h"
 #include "lfs_util.h"
 
+#include <inttypes.h>
+
 
 /// Caching block device operations ///
 static int lfs_cache_read(lfs_t *lfs, lfs_cache_t *rcache,
@@ -107,6 +109,19 @@ static int lfs_cache_crc(lfs_t *lfs, lfs_cache_t *rcache,
     return 0;
 }
 
+static inline void lfs_cache_drop(lfs_t *lfs, lfs_cache_t *rcache) {
+    // do not zero, cheaper if cache is readonly or only going to be
+    // written with identical data (during relocates)
+    (void)lfs;
+    rcache->block = 0xffffffff;
+}
+
+static inline void lfs_cache_zero(lfs_t *lfs, lfs_cache_t *pcache) {
+    // zero to avoid information leak
+    memset(pcache->buffer, 0xff, lfs->cfg->prog_size);
+    pcache->block = 0xffffffff;
+}
+
 static int lfs_cache_flush(lfs_t *lfs,
         lfs_cache_t *pcache, lfs_cache_t *rcache) {
     if (pcache->block != 0xffffffff) {
@@ -128,7 +143,7 @@ static int lfs_cache_flush(lfs_t *lfs,
             }
         }
 
-        pcache->block = 0xffffffff;
+        lfs_cache_zero(lfs, pcache);
     }
 
     return 0;
@@ -233,7 +248,7 @@ static int lfs_bd_erase(lfs_t *lfs, lfs_block_t block) {
 }
 
 static int lfs_bd_sync(lfs_t *lfs) {
-    lfs->rcache.block = 0xffffffff;
+    lfs_cache_drop(lfs, &lfs->rcache);
 
     int err = lfs_cache_flush(lfs, &lfs->pcache, NULL);
     if (err) {
@@ -295,7 +310,8 @@ static int lfs_alloc(lfs_t *lfs, lfs_block_t *block) {
 
         // check if we have looked at all blocks since last ack
         if (lfs->free.ack == 0) {
-            LFS_WARN("No more free space %d", lfs->free.i + lfs->free.off);
+            LFS_WARN("No more free space %" PRIu32,
+                    lfs->free.i + lfs->free.off);
             return LFS_ERR_NOSPC;
         }
 
@@ -401,11 +417,14 @@ static int lfs_dir_alloc(lfs_t *lfs, lfs_dir_t *dir) {
     // rather than clobbering one of the blocks we just pretend
     // the revision may be valid
     int err = lfs_bd_read(lfs, dir->pair[0], 0, &dir->d.rev, 4);
-    dir->d.rev = lfs_fromle32(dir->d.rev);
+    if (err && err != LFS_ERR_CORRUPT) {
-    if (err) {
         return err;
     }
 
+    if (err != LFS_ERR_CORRUPT) {
+        dir->d.rev = lfs_fromle32(dir->d.rev);
+    }
+
     // set defaults
     dir->d.rev += 1;
     dir->d.size = sizeof(dir->d)+4;
@@ -429,6 +448,9 @@ static int lfs_dir_fetch(lfs_t *lfs,
         int err = lfs_bd_read(lfs, tpair[i], 0, &test, sizeof(test));
         lfs_dir_fromle32(&test);
         if (err) {
+            if (err == LFS_ERR_CORRUPT) {
+                continue;
+            }
             return err;
         }
 
@@ -448,6 +470,9 @@ static int lfs_dir_fetch(lfs_t *lfs,
         err = lfs_bd_crc(lfs, tpair[i], sizeof(test),
                 (0x7fffffff & test.size) - sizeof(test), &crc);
         if (err) {
+            if (err == LFS_ERR_CORRUPT) {
+                continue;
+            }
             return err;
         }
 
@@ -465,7 +490,8 @@ static int lfs_dir_fetch(lfs_t *lfs,
     }
 
     if (!valid) {
-        LFS_ERROR("Corrupted dir pair at %d %d", tpair[0], tpair[1]);
+        LFS_ERROR("Corrupted dir pair at %" PRIu32 " %" PRIu32 ,
+                tpair[0], tpair[1]);
         return LFS_ERR_CORRUPT;
     }
 
@@ -588,15 +614,16 @@ static int lfs_dir_commit(lfs_t *lfs, lfs_dir_t *dir,
         break;
 relocate:
         //commit was corrupted
-        LFS_DEBUG("Bad block at %d", dir->pair[0]);
+        LFS_DEBUG("Bad block at %" PRIu32, dir->pair[0]);
 
         // drop caches and prepare to relocate block
         relocated = true;
-        lfs->pcache.block = 0xffffffff;
+        lfs_cache_drop(lfs, &lfs->pcache);
 
         // can't relocate superblock, filesystem is now frozen
         if (lfs_paircmp(oldpair, (const lfs_block_t[2]){0, 1}) == 0) {
-            LFS_WARN("Superblock %d has become unwritable", oldpair[0]);
+            LFS_WARN("Superblock %" PRIu32 " has become unwritable",
+                    oldpair[0]);
             return LFS_ERR_CORRUPT;
         }
 
@@ -609,7 +636,7 @@ relocate:
 
     if (relocated) {
         // update references if we relocated
-        LFS_DEBUG("Relocating %d %d to %d %d",
+        LFS_DEBUG("Relocating %" PRIu32 " %" PRIu32 " to %" PRIu32 " %" PRIu32,
                 oldpair[0], oldpair[1], dir->pair[0], dir->pair[1]);
         int err = lfs_relocate(lfs, oldpair, dir->pair);
         if (err) {
@@ -836,7 +863,7 @@ nextname:
 
         // find entry matching name
         while (true) {
-            int err = lfs_dir_next(lfs, dir, entry);
+            err = lfs_dir_next(lfs, dir, entry);
             if (err) {
                 return err;
             }
@@ -1214,10 +1241,10 @@ static int lfs_ctz_extend(lfs_t *lfs,
         }
 
 relocate:
-        LFS_DEBUG("Bad block at %d", nblock);
+        LFS_DEBUG("Bad block at %" PRIu32, nblock);
 
         // just clear cache and try a new block
-        pcache->block = 0xffffffff;
+        lfs_cache_drop(lfs, &lfs->pcache);
     }
 }
 
@@ -1264,8 +1291,9 @@ static int lfs_ctz_traverse(lfs_t *lfs,
 
 
 /// Top level file operations ///
-int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
+int lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file,
-        const char *path, int flags) {
+        const char *path, int flags,
+        const struct lfs_file_config *cfg) {
     // deorphan if we haven't yet, needed at most once after poweron
     if ((flags & 3) != LFS_O_RDONLY && !lfs->deorphaned) {
         int err = lfs_deorphan(lfs);
@@ -1305,6 +1333,7 @@ int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
     }
 
     // setup file struct
+    file->cfg = cfg;
     file->pair[0] = cwd.pair[0];
     file->pair[1] = cwd.pair[1];
     file->poff = entry.off;
@@ -1323,7 +1352,9 @@ int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
 
     // allocate buffer if needed
     file->cache.block = 0xffffffff;
-    if (lfs->cfg->file_buffer) {
+    if (file->cfg && file->cfg->buffer) {
+        file->cache.buffer = file->cfg->buffer;
+    } else if (lfs->cfg->file_buffer) {
         if (lfs->files) {
             // already in use
             return LFS_ERR_NOMEM;
@@ -1341,6 +1372,12 @@ int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
         }
     }
 
+    // zero to avoid information leak
+    lfs_cache_drop(lfs, &file->cache);
+    if ((file->flags & 3) != LFS_O_RDONLY) {
+        lfs_cache_zero(lfs, &file->cache);
+    }
+
     // add to list of files
     file->next = lfs->files;
     lfs->files = file;
@@ -1348,6 +1385,11 @@ int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
     return 0;
 }
 
+int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
+        const char *path, int flags) {
+    return lfs_file_opencfg(lfs, file, path, flags, NULL);
+}
+
 int lfs_file_close(lfs_t *lfs, lfs_file_t *file) {
     int err = lfs_file_sync(lfs, file);
 
@@ -1360,7 +1402,7 @@ int lfs_file_close(lfs_t *lfs, lfs_file_t *file) {
     }
 
     // clean up memory
-    if (!lfs->cfg->file_buffer) {
+    if (!(file->cfg && file->cfg->buffer) && !lfs->cfg->file_buffer) {
         lfs_free(file->cache.buffer);
     }
 
@@ -1369,7 +1411,7 @@ int lfs_file_close(lfs_t *lfs, lfs_file_t *file) {
 
 static int lfs_file_relocate(lfs_t *lfs, lfs_file_t *file) {
 relocate:
-    LFS_DEBUG("Bad block at %d", file->block);
+    LFS_DEBUG("Bad block at %" PRIu32, file->block);
 
     // just relocate what exists into new block
     lfs_block_t nblock;
@@ -1409,7 +1451,7 @@ relocate:
     memcpy(file->cache.buffer, lfs->pcache.buffer, lfs->cfg->prog_size);
     file->cache.block = lfs->pcache.block;
     file->cache.off = lfs->pcache.off;
-    lfs->pcache.block = 0xffffffff;
+    lfs_cache_zero(lfs, &lfs->pcache);
 
     file->block = nblock;
     return 0;
@@ -1418,7 +1460,7 @@ relocate:
 static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
     if (file->flags & LFS_F_READING) {
         // just drop read cache
-        file->cache.block = 0xffffffff;
+        lfs_cache_drop(lfs, &file->cache);
         file->flags &= ~LFS_F_READING;
     }
 
@@ -1433,7 +1475,7 @@ static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
             .pos = file->pos,
             .cache = lfs->rcache,
         };
-        lfs->rcache.block = 0xffffffff;
+        lfs_cache_drop(lfs, &lfs->rcache);
 
         while (file->pos < file->size) {
             // copy over a byte at a time, leave it up to caching
@@ -1451,8 +1493,8 @@ static int lfs_file_flush(lfs_t *lfs, lfs_file_t *file) {
 
             // keep our reference to the rcache in sync
             if (lfs->rcache.block != 0xffffffff) {
-                orig.cache.block = 0xffffffff;
+                lfs_cache_drop(lfs, &orig.cache);
-                lfs->rcache.block = 0xffffffff;
+                lfs_cache_drop(lfs, &lfs->rcache);
             }
         }
 
@@ -1630,7 +1672,7 @@ lfs_ssize_t lfs_file_write(lfs_t *lfs, lfs_file_t *file,
                 }
 
                 // mark cache as dirty since we may have read data into it
-                file->cache.block = 0xffffffff;
+                lfs_cache_zero(lfs, &file->cache);
             }
 
             // extend file with new blocks
@@ -1977,31 +2019,48 @@ int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath) {
 
 
 /// Filesystem operations ///
+static void lfs_deinit(lfs_t *lfs) {
+    // free allocated memory
+    if (!lfs->cfg->read_buffer) {
+        lfs_free(lfs->rcache.buffer);
+    }
+
+    if (!lfs->cfg->prog_buffer) {
+        lfs_free(lfs->pcache.buffer);
+    }
+
+    if (!lfs->cfg->lookahead_buffer) {
+        lfs_free(lfs->free.buffer);
+    }
+}
+
 static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
     lfs->cfg = cfg;
 
     // setup read cache
-    lfs->rcache.block = 0xffffffff;
     if (lfs->cfg->read_buffer) {
         lfs->rcache.buffer = lfs->cfg->read_buffer;
     } else {
         lfs->rcache.buffer = lfs_malloc(lfs->cfg->read_size);
         if (!lfs->rcache.buffer) {
-            return LFS_ERR_NOMEM;
+            goto cleanup;
         }
     }
 
     // setup program cache
-    lfs->pcache.block = 0xffffffff;
     if (lfs->cfg->prog_buffer) {
         lfs->pcache.buffer = lfs->cfg->prog_buffer;
     } else {
         lfs->pcache.buffer = lfs_malloc(lfs->cfg->prog_size);
         if (!lfs->pcache.buffer) {
-            return LFS_ERR_NOMEM;
+            goto cleanup;
         }
     }
 
+    // zero to avoid information leaks
+    lfs_cache_zero(lfs, &lfs->pcache);
+    lfs_cache_drop(lfs, &lfs->rcache);
+
     // setup lookahead, round down to nearest 32-bits
     LFS_ASSERT(lfs->cfg->lookahead % 32 == 0);
     LFS_ASSERT(lfs->cfg->lookahead > 0);
@@ -2010,7 +2069,7 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
     } else {
         lfs->free.buffer = lfs_malloc(lfs->cfg->lookahead/8);
         if (!lfs->free.buffer) {
-            return LFS_ERR_NOMEM;
+            goto cleanup;
         }
     }
 
@@ -2030,155 +2089,160 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
     lfs->deorphaned = false;
 
     return 0;
-}
 
-static int lfs_deinit(lfs_t *lfs) {
+cleanup:
-    // free allocated memory
+    lfs_deinit(lfs);
-    if (!lfs->cfg->read_buffer) {
+    return LFS_ERR_NOMEM;
-        lfs_free(lfs->rcache.buffer);
-    }
-
-    if (!lfs->cfg->prog_buffer) {
-        lfs_free(lfs->pcache.buffer);
-    }
-
-    if (!lfs->cfg->lookahead_buffer) {
-        lfs_free(lfs->free.buffer);
-    }
-
-    return 0;
 }
 
 int lfs_format(lfs_t *lfs, const struct lfs_config *cfg) {
-    int err = lfs_init(lfs, cfg);
+    int err = 0;
-    if (err) {
+    if (true) {
-        return err;
+        err = lfs_init(lfs, cfg);
-    }
-
-    // create free lookahead
-    memset(lfs->free.buffer, 0, lfs->cfg->lookahead/8);
-    lfs->free.off = 0;
-    lfs->free.size = lfs_min(lfs->cfg->lookahead, lfs->cfg->block_count);
-    lfs->free.i = 0;
-    lfs_alloc_ack(lfs);
-
-    // create superblock dir
-    lfs_dir_t superdir;
-    err = lfs_dir_alloc(lfs, &superdir);
-    if (err) {
-        return err;
-    }
-
-    // write root directory
-    lfs_dir_t root;
-    err = lfs_dir_alloc(lfs, &root);
-    if (err) {
-        return err;
-    }
-
-    err = lfs_dir_commit(lfs, &root, NULL, 0);
-    if (err) {
-        return err;
-    }
-
-    lfs->root[0] = root.pair[0];
-    lfs->root[1] = root.pair[1];
-
-    // write superblocks
-    lfs_superblock_t superblock = {
-        .off = sizeof(superdir.d),
-        .d.type = LFS_TYPE_SUPERBLOCK,
-        .d.elen = sizeof(superblock.d) - sizeof(superblock.d.magic) - 4,
-        .d.nlen = sizeof(superblock.d.magic),
-        .d.version = LFS_DISK_VERSION,
-        .d.magic = {"littlefs"},
-        .d.block_size  = lfs->cfg->block_size,
-        .d.block_count = lfs->cfg->block_count,
-        .d.root = {lfs->root[0], lfs->root[1]},
-    };
-    superdir.d.tail[0] = root.pair[0];
-    superdir.d.tail[1] = root.pair[1];
-    superdir.d.size = sizeof(superdir.d) + sizeof(superblock.d) + 4;
-
-    // write both pairs to be safe
-    lfs_superblock_tole32(&superblock.d);
-    bool valid = false;
-    for (int i = 0; i < 2; i++) {
-        err = lfs_dir_commit(lfs, &superdir, (struct lfs_region[]){
-                {sizeof(superdir.d), sizeof(superblock.d),
-                 &superblock.d, sizeof(superblock.d)}
-            }, 1);
-        if (err && err != LFS_ERR_CORRUPT) {
-            return err;
-        }
-
-        valid = valid || !err;
-    }
-
-    if (!valid) {
-        return LFS_ERR_CORRUPT;
-    }
-
-    // sanity check that fetch works
-    err = lfs_dir_fetch(lfs, &superdir, (const lfs_block_t[2]){0, 1});
-    if (err) {
-        return err;
-    }
-
-    lfs_alloc_ack(lfs);
-    return lfs_deinit(lfs);
-}
-
-int lfs_mount(lfs_t *lfs, const struct lfs_config *cfg) {
-    int err = lfs_init(lfs, cfg);
-    if (err) {
-        return err;
-    }
-
-    // setup free lookahead
-    lfs->free.off = 0;
-    lfs->free.size = 0;
-    lfs->free.i = 0;
-    lfs_alloc_ack(lfs);
-
-    // load superblock
-    lfs_dir_t dir;
-    lfs_superblock_t superblock;
-    err = lfs_dir_fetch(lfs, &dir, (const lfs_block_t[2]){0, 1});
-    if (err && err != LFS_ERR_CORRUPT) {
-        return err;
-    }
-
-    if (!err) {
-        err = lfs_bd_read(lfs, dir.pair[0], sizeof(dir.d),
-                &superblock.d, sizeof(superblock.d));
-        lfs_superblock_fromle32(&superblock.d);
         if (err) {
             return err;
         }
 
-        lfs->root[0] = superblock.d.root[0];
+        // create free lookahead
-        lfs->root[1] = superblock.d.root[1];
+        memset(lfs->free.buffer, 0, lfs->cfg->lookahead/8);
+        lfs->free.off = 0;
+        lfs->free.size = lfs_min(lfs->cfg->lookahead, lfs->cfg->block_count);
+        lfs->free.i = 0;
+        lfs_alloc_ack(lfs);
+
+        // create superblock dir
+        lfs_dir_t superdir;
+        err = lfs_dir_alloc(lfs, &superdir);
+        if (err) {
+            goto cleanup;
+        }
+
+        // write root directory
+        lfs_dir_t root;
+        err = lfs_dir_alloc(lfs, &root);
+        if (err) {
+            goto cleanup;
+        }
+
+        err = lfs_dir_commit(lfs, &root, NULL, 0);
+        if (err) {
+            goto cleanup;
+        }
+
+        lfs->root[0] = root.pair[0];
+        lfs->root[1] = root.pair[1];
+
+        // write superblocks
+        lfs_superblock_t superblock = {
+            .off = sizeof(superdir.d),
+            .d.type = LFS_TYPE_SUPERBLOCK,
+            .d.elen = sizeof(superblock.d) - sizeof(superblock.d.magic) - 4,
+            .d.nlen = sizeof(superblock.d.magic),
+            .d.version = LFS_DISK_VERSION,
+            .d.magic = {"littlefs"},
+            .d.block_size  = lfs->cfg->block_size,
+            .d.block_count = lfs->cfg->block_count,
+            .d.root = {lfs->root[0], lfs->root[1]},
+        };
+        superdir.d.tail[0] = root.pair[0];
+        superdir.d.tail[1] = root.pair[1];
+        superdir.d.size = sizeof(superdir.d) + sizeof(superblock.d) + 4;
+
+        // write both pairs to be safe
+        lfs_superblock_tole32(&superblock.d);
+        bool valid = false;
+        for (int i = 0; i < 2; i++) {
+            err = lfs_dir_commit(lfs, &superdir, (struct lfs_region[]){
+                    {sizeof(superdir.d), sizeof(superblock.d),
+                     &superblock.d, sizeof(superblock.d)}
+                }, 1);
+            if (err && err != LFS_ERR_CORRUPT) {
+                goto cleanup;
+            }
+
+            valid = valid || !err;
+        }
+
+        if (!valid) {
+            err = LFS_ERR_CORRUPT;
+            goto cleanup;
+        }
+
+        // sanity check that fetch works
+        err = lfs_dir_fetch(lfs, &superdir, (const lfs_block_t[2]){0, 1});
+        if (err) {
+            goto cleanup;
+        }
+
+        lfs_alloc_ack(lfs);
     }
 
-    if (err || memcmp(superblock.d.magic, "littlefs", 8) != 0) {
+cleanup:
-        LFS_ERROR("Invalid superblock at %d %d", 0, 1);
+    lfs_deinit(lfs);
-        return LFS_ERR_CORRUPT;
+    return err;
+}
+
+int lfs_mount(lfs_t *lfs, const struct lfs_config *cfg) {
+    int err = 0;
+    if (true) {
+        err = lfs_init(lfs, cfg);
+        if (err) {
+            return err;
+        }
+
+        // setup free lookahead
+        lfs->free.off = 0;
+        lfs->free.size = 0;
+        lfs->free.i = 0;
+        lfs_alloc_ack(lfs);
+
+        // load superblock
+        lfs_dir_t dir;
+        lfs_superblock_t superblock;
+        err = lfs_dir_fetch(lfs, &dir, (const lfs_block_t[2]){0, 1});
+        if (err && err != LFS_ERR_CORRUPT) {
+            goto cleanup;
+        }
+
+        if (!err) {
+            err = lfs_bd_read(lfs, dir.pair[0], sizeof(dir.d),
+                    &superblock.d, sizeof(superblock.d));
+            lfs_superblock_fromle32(&superblock.d);
+            if (err) {
+                goto cleanup;
+            }
+
+            lfs->root[0] = superblock.d.root[0];
+            lfs->root[1] = superblock.d.root[1];
+        }
+
+        if (err || memcmp(superblock.d.magic, "littlefs", 8) != 0) {
+            LFS_ERROR("Invalid superblock at %d %d", 0, 1);
+            err = LFS_ERR_CORRUPT;
+            goto cleanup;
+        }
+
+        uint16_t major_version = (0xffff & (superblock.d.version >> 16));
+        uint16_t minor_version = (0xffff & (superblock.d.version >>  0));
+        if ((major_version != LFS_DISK_VERSION_MAJOR ||
+             minor_version > LFS_DISK_VERSION_MINOR)) {
+            LFS_ERROR("Invalid version %d.%d", major_version, minor_version);
+            err = LFS_ERR_INVAL;
+            goto cleanup;
+        }
+
+        return 0;
     }
 
-    uint16_t major_version = (0xffff & (superblock.d.version >> 16));
+cleanup:
-    uint16_t minor_version = (0xffff & (superblock.d.version >>  0));
-    if ((major_version != LFS_DISK_VERSION_MAJOR ||
-         minor_version > LFS_DISK_VERSION_MINOR)) {
-        LFS_ERROR("Invalid version %d.%d", major_version, minor_version);
-        return LFS_ERR_INVAL;
-    }
 
-    return 0;
+    lfs_deinit(lfs);
+    return err;
 }
 
 int lfs_unmount(lfs_t *lfs) {
-    return lfs_deinit(lfs);
+    lfs_deinit(lfs);
+    return 0;
 }
 
 
@@ -2378,7 +2442,8 @@ static int lfs_relocate(lfs_t *lfs,
 
         // update internal root
         if (lfs_paircmp(oldpair, lfs->root) == 0) {
-            LFS_DEBUG("Relocating root %d %d", newpair[0], newpair[1]);
+            LFS_DEBUG("Relocating root %" PRIu32 " %" PRIu32,
+                    newpair[0], newpair[1]);
             lfs->root[0] = newpair[0];
             lfs->root[1] = newpair[1];
         }
@@ -2416,7 +2481,11 @@ int lfs_deorphan(lfs_t *lfs) {
     lfs_dir_t cwd = {.d.tail[0] = 0, .d.tail[1] = 1};
 
     // iterate over all directory directory entries
-    while (!lfs_pairisnull(cwd.d.tail)) {
+    for (lfs_size_t i = 0; i < lfs->cfg->block_count; i++) {
+        if (lfs_pairisnull(cwd.d.tail)) {
+            return 0;
+        }
+
         int err = lfs_dir_fetch(lfs, &cwd, cwd.d.tail);
         if (err) {
             return err;
@@ -2434,7 +2503,7 @@ int lfs_deorphan(lfs_t *lfs) {
 
             if (!res) {
                 // we are an orphan
-                LFS_DEBUG("Found orphan %d %d",
+                LFS_DEBUG("Found orphan %" PRIu32 " %" PRIu32,
                         pdir.d.tail[0], pdir.d.tail[1]);
 
                 pdir.d.tail[0] = cwd.d.tail[0];
@@ -2445,12 +2514,12 @@ int lfs_deorphan(lfs_t *lfs) {
                     return err;
                 }
 
-                break;
+                return 0;
             }
 
             if (!lfs_pairsync(entry.d.u.dir, pdir.d.tail)) {
                 // we have desynced
-                LFS_DEBUG("Found desync %d %d",
+                LFS_DEBUG("Found desync %" PRIu32 " %" PRIu32,
                         entry.d.u.dir[0], entry.d.u.dir[1]);
 
                 pdir.d.tail[0] = entry.d.u.dir[0];
@@ -2461,7 +2530,7 @@ int lfs_deorphan(lfs_t *lfs) {
                     return err;
                 }
 
-                break;
+                return 0;
             }
         }
 
@@ -2485,14 +2554,14 @@ int lfs_deorphan(lfs_t *lfs) {
                 }
 
                 if (moved) {
-                    LFS_DEBUG("Found move %d %d",
+                    LFS_DEBUG("Found move %" PRIu32 " %" PRIu32,
                             entry.d.u.dir[0], entry.d.u.dir[1]);
                     err = lfs_dir_remove(lfs, &cwd, &entry);
                     if (err) {
                         return err;
                     }
                 } else {
-                    LFS_DEBUG("Found partial move %d %d",
+                    LFS_DEBUG("Found partial move %" PRIu32 " %" PRIu32,
                             entry.d.u.dir[0], entry.d.u.dir[1]);
                     entry.d.type &= ~0x80;
                     err = lfs_dir_update(lfs, &cwd, &entry, NULL);
@@ -2506,6 +2575,7 @@ int lfs_deorphan(lfs_t *lfs) {
         memcpy(&pdir, &cwd, sizeof(pdir));
     }
 
-    return 0;
+    // If we reached here, we have more directory pairs than blocks in the
+    // filesystem... So something must be horribly wrong
+    return LFS_ERR_CORRUPT;
 }
-

lfs.h

@@ -10,13 +10,18 @@
 #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 0x00010004
+#define LFS_VERSION 0x00010006
 #define LFS_VERSION_MAJOR (0xffff & (LFS_VERSION >> 16))
 #define LFS_VERSION_MINOR (0xffff & (LFS_VERSION >>  0))
 
@@ -162,6 +167,12 @@ 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 {
@@ -209,6 +220,7 @@ 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;
@@ -276,7 +288,8 @@ 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.
+// object, and does not leave the filesystem mounted. The config struct must
+// be zeroed for defaults and backwards compatibility.
 //
 // Returns a negative error code on failure.
 int lfs_format(lfs_t *lfs, const struct lfs_config *config);
@@ -285,7 +298,8 @@ 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.
+// lfs and config must be allocated while mounted. The config struct must
+// be zeroed for defaults and backwards compatibility.
 //
 // Returns a negative error code on failure.
 int lfs_mount(lfs_t *lfs, const struct lfs_config *config);
@@ -323,14 +337,27 @@ 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
+// The mode that the file is opened in is determined by the flags, which
-// by the flags, which are values from the enum lfs_open_flags
+// are values from the enum lfs_open_flags that are bitwise-ored together.
-// 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
@@ -460,4 +487,8 @@ 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

lfs_util.h

@@ -34,6 +34,11 @@
 #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
@@ -158,6 +163,7 @@ static inline void *lfs_malloc(size_t size) {
 #ifndef LFS_NO_MALLOC
     return malloc(size);
 #else
+    (void)size;
     return NULL;
 #endif
 }
@@ -166,9 +172,15 @@ static inline void *lfs_malloc(size_t size) {
 static inline void lfs_free(void *p) {
 #ifndef LFS_NO_MALLOC
     free(p);
+#else
+    (void)p;
 #endif
 }
 
 
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
 #endif
 #endif

tests/test_alloc.sh

@@ -32,18 +32,18 @@ lfs_alloc_singleproc() {
 tests/test.py << TEST
     const char *names[] = {"bacon", "eggs", "pancakes"};
     lfs_mount(&lfs, &cfg) => 0;
-    for (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
+    for (unsigned 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 (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
+    for (unsigned 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 (int n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
+    for (unsigned n = 0; n < sizeof(names)/sizeof(names[0]); n++) {
         lfs_file_close(&lfs, &file[n]) => 0;
     }
     lfs_unmount(&lfs) => 0;

tests/test_files.sh

@@ -30,7 +30,7 @@ TEST
 
 w_test() {
 tests/test.py << TEST
-    lfs_size_t size = $1;
+    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
-    lfs_size_t size = $1;
+    size = $1;
     lfs_size_t chunk = 29;
     srand(0);
     lfs_mount(&lfs, &cfg) => 0;

tests/test_seek.sh

@@ -153,7 +153,7 @@ tests/test.py << TEST
     lfs_file_read(&lfs, &file[0], buffer, size) => size;
     memcmp(buffer, "kittycatcat", size) => 0;
 
-    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    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;
 
-    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    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;
 
-    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    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;
 
-    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    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 (int i = 0; i < sizeof(offsets) / sizeof(offsets[0]); i++) {
+    for (unsigned 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;

tests/test_truncate.sh

@@ -23,14 +23,14 @@ tests/test.py << TEST
 
     lfs_mount(&lfs, &cfg) => 0;
 
-    for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
+    for (unsigned 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 (int j = 0; j < startsizes[i]; j += size) {
+        for (lfs_off_t j = 0; j < startsizes[i]; j += size) {
             lfs_file_write(&lfs, &file[0], buffer, size) => size;
         }
         lfs_file_size(&lfs, &file[0]) => startsizes[i];
@@ -55,13 +55,13 @@ tests/test.py << TEST
 
     lfs_mount(&lfs, &cfg) => 0;
 
-    for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
+    for (unsigned 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");
-        int j = 0;
+        lfs_off_t 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 +87,13 @@ tests/test.py << TEST
 
     lfs_mount(&lfs, &cfg) => 0;
 
-    for (int i = 0; i < sizeof(startsizes)/sizeof(startsizes[0]); i++) {
+    for (unsigned 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");
-        int j = 0;
+        lfs_off_t j = 0;
         for (; j < startsizes[i] && j < hotsizes[i] && j < coldsizes[i];
                 j += size) {
             lfs_file_read(&lfs, &file[0], buffer, size) => size;