paths: Changed CREAT with a trailing slash to return NOTDIR

- before: lfs_file_open("missing/") => LFS_ERR_ISDIR - after: lfs_file_open("missing/") => LFS_ERR_NOTDIR As noted by bmcdonnell-fb, returning LFS_ERR_ISDIR here was inconsistent with the case where the file exists: case before after lfs_file_open("dir_a") => LFS_ERR_ISDIR LFS_ERR_ISDIR lfs_file_open("dir_a/") => LFS_ERR_ISDIR LFS_ERR_ISDIR lfs_file_open("reg_a/") => LFS_ERR_NOTDIR LFS_ERR_NOTDIR lfs_file_open("missing_a/") => LFS_ERR_ISDIR LFS_ERR_NOTDIR Note this is consistent with the behavior of lfs_stat: lfs_file_open("reg_a/") => LFS_ERR_NOTDIR lfs_stat("reg_a/") => LFS_ERR_NOTDIR And the only other function that can "create" files, lfs_rename: lfs_file_open("missing_a/") => LFS_ERR_NOTDIR lfs_rename("reg_a", "missing_a/") => LFS_ERR_NOTDIR There is some ongoing discussion about if these should return NOTDIR, ISDIR, or INVAL, but this is at least an improvement over the rename/open mismatch.
paths: Added tests over NOENT + trailing slash/dot
2024-11-25 15:40:44 -06:00 · 2024-11-25 15:40:15 -06:00 · 2024-11-25 15:40:15 -06:00 · 2024-11-25 15:40:15 -06:00 · 2024-11-25 15:40:15 -06:00 · 2024-11-25 15:40:07 -06:00
8 changed files with 7474 additions and 309 deletions
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -20,7 +20,7 @@ jobs:
      github.event.workflow_run.head_sha == github.sha}}

    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        with:
          ref: ${{github.event.workflow_run.head_sha}}
          # need workflow access since we push branches
@@ -30,26 +30,29 @@ jobs:
          fetch-depth: 0

      # try to get results from tests
-      - uses: dawidd6/action-download-artifact@v2
+      - uses: actions/download-artifact@v4
        continue-on-error: true
        with:
-          workflow: ${{github.event.workflow_run.name}}
-          run_id: ${{github.event.workflow_run.id}}
-          name: sizes
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          run-id: ${{github.event.workflow_run.id}}
+          pattern: '{sizes,sizes-*}'
+          merge-multiple: true
          path: sizes
-      - uses: dawidd6/action-download-artifact@v2
+      - uses: actions/download-artifact@v4
        continue-on-error: true
        with:
-          workflow: ${{github.event.workflow_run.name}}
-          run_id: ${{github.event.workflow_run.id}}
-          name: cov
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          run-id: ${{github.event.workflow_run.id}}
+          pattern: '{cov,cov-*}'
+          merge-multiple: true
          path: cov
-      - uses: dawidd6/action-download-artifact@v2
+      - uses: actions/download-artifact@v4
        continue-on-error: true
        with:
-          workflow: ${{github.event.workflow_run.name}}
-          run_id: ${{github.event.workflow_run.id}}
-          name: bench
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          run-id: ${{github.event.workflow_run.id}}
+          pattern: '{bench,bench-*}'
+          merge-multiple: true
          path: bench

      - name: find-version
--- a/.github/workflows/status.yml
+++ b/.github/workflows/status.yml
@@ -13,12 +13,13 @@ jobs:
  status:
    runs-on: ubuntu-latest
    steps:
-      - uses: dawidd6/action-download-artifact@v2
+      - uses: actions/download-artifact@v4
        continue-on-error: true
        with:
-          workflow: ${{github.event.workflow_run.name}}
-          run_id: ${{github.event.workflow_run.id}}
-          name: status
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          run-id: ${{github.event.workflow_run.id}}
+          pattern: '{status,status-*}'
+          merge-multiple: true
          path: status
      - name: update-status
        continue-on-error: true
@@ -67,12 +68,13 @@ jobs:

    steps:
      # generated comment?
-      - uses: dawidd6/action-download-artifact@v2
+      - uses: actions/download-artifact@v4
        continue-on-error: true
        with:
-          workflow: ${{github.event.workflow_run.name}}
-          run_id: ${{github.event.workflow_run.id}}
-          name: comment
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          run-id: ${{github.event.workflow_run.id}}
+          pattern: '{comment,comment-*}'
+          merge-multiple: true
          path: comment
      - name: update-comment
        continue-on-error: true
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -21,7 +21,7 @@ jobs:
        arch: [x86_64, thumb, mips, powerpc]

    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -235,9 +235,9 @@ jobs:

      # create size statuses
      - name: upload-sizes
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
-          name: sizes
+          name: sizes-${{matrix.arch}}
          path: sizes
      - name: status-sizes
        run: |
@@ -273,16 +273,17 @@ jobs:
            }' | tee status/$(basename $f .csv).json
          done
      - name: upload-status-sizes
-        uses: actions/upload-artifact@v2
+        if: ${{matrix.arch == 'x86_64'}}
+        uses: actions/upload-artifact@v4
        with:
-          name: status
+          name: status-sizes-${{matrix.arch}}
          path: status
          retention-days: 1

      # create cov statuses
      - name: upload-cov
        if: ${{matrix.arch == 'x86_64'}}
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
          name: cov
          path: cov
@@ -317,11 +318,11 @@ jobs:
              target_step: env.STEP,
            }' | tee status/$(basename $f .csv)-$s.json
          done
-      - name: upload-status-sizes
+      - name: upload-status-cov
        if: ${{matrix.arch == 'x86_64'}}
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
-          name: status
+          name: status-cov
          path: status
          retention-days: 1

@@ -336,7 +337,7 @@ jobs:
        pls: [1, 2]

    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -361,7 +362,7 @@ jobs:
  test-no-intrinsics:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -378,7 +379,7 @@ jobs:
  test-multiversion:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -395,7 +396,7 @@ jobs:
  test-lfs2_0:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -414,7 +415,7 @@ jobs:
  test-valgrind:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -436,7 +437,7 @@ jobs:
  test-clang:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -459,7 +460,7 @@ jobs:
  bench:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -491,7 +492,7 @@ jobs:

      # create bench statuses
      - name: upload-bench
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
          name: bench
          path: bench
@@ -525,9 +526,9 @@ jobs:
            }' | tee status/$(basename $f .csv)-$s.json
          done
      - name: upload-status-bench
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
-          name: status
+          name: status-bench
          path: status
          retention-days: 1

@@ -535,10 +536,10 @@ jobs:
  test-compat:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        if: ${{github.event_name == 'pull_request'}}
      # checkout the current pr target into lfsp
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        if: ${{github.event_name == 'pull_request'}}
        with:
          ref: ${{github.event.pull_request.base.ref}}
@@ -572,7 +573,7 @@ jobs:
    runs-on: ubuntu-latest
    if: ${{!endsWith(github.ref, '-prefix')}}
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -582,7 +583,7 @@ jobs:
          gcc --version
          python3 --version
          fusermount -V
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v2
@@ -622,7 +623,7 @@ jobs:
    runs-on: ubuntu-latest
    if: ${{!endsWith(github.ref, '-prefix')}}
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
      - name: install
        run: |
          # need a few things
@@ -632,12 +633,12 @@ jobs:
          gcc --version
          python3 --version
          fusermount -V
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v2
          path: v2
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v1
@@ -694,7 +695,7 @@ jobs:
    runs-on: ubuntu-latest
    needs: [test, bench]
    steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
        if: ${{github.event_name == 'pull_request'}}
      - name: install
        if: ${{github.event_name == 'pull_request'}}
@@ -704,23 +705,26 @@ jobs:
          pip3 install toml
          gcc --version
          python3 --version
-      - uses: actions/download-artifact@v2
+      - uses: actions/download-artifact@v4
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
-          name: sizes
+          pattern: '{sizes,sizes-*}'
+          merge-multiple: true
          path: sizes
-      - uses: actions/download-artifact@v2
+      - uses: actions/download-artifact@v4
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
-          name: cov
+          pattern: '{cov,cov-*}'
+          merge-multiple: true
          path: cov
-      - uses: actions/download-artifact@v2
+      - uses: actions/download-artifact@v4
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
-          name: bench
+          pattern: '{bench,bench-*}'
+          merge-multiple: true
          path: bench

      # try to find results from tests
@@ -862,7 +866,7 @@ jobs:
            body: $comment,
          }' | tee comment/comment.json
      - name: upload-comment
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
        with:
          name: comment
          path: comment
--- a/README.md
+++ b/README.md
@@ -231,11 +231,25 @@ License Identifiers that are here available: http://spdx.org/licenses/
  to use littlefs in a Rust-friendly API, reaping the benefits of Rust's memory
  safety and other guarantees.

+- [nim-littlefs] - A Nim wrapper and API for littlefs. Includes a fuse
+  implementation based on [littlefs-fuse]
+
+- [chamelon] - A pure-OCaml implementation of (most of) littlefs, designed for
+  use with the MirageOS library operating system project. It is interoperable
+  with the reference implementation, with some caveats.
+
 - [littlefs-disk-img-viewer] - A memory-efficient web application for viewing
  littlefs disk images in your web browser.

- [mklfs] - A command line tool built by the [Lua RTOS] guys for making
-  littlefs images from a host PC. Supports Windows, Mac OS, and Linux.
+- [mklfs] - A command line tool for creating littlefs images. Used in the Lua
+  RTOS ecosystem.
+
+- [mklittlefs] - A command line tool for creating littlefs images. Used in the
+  ESP8266 and RP2040 ecosystem.
+
+- [pico-littlefs-usb] - An interface for littlefs that emulates a FAT12
+  filesystem over USB. Allows mounting littlefs on a host PC without additional
+  drivers.

 - [Mbed OS] - The easiest way to get started with littlefs is to jump into Mbed
  which already has block device drivers for most forms of embedded storage.
@@ -254,27 +268,21 @@ License Identifiers that are here available: http://spdx.org/licenses/
  for microcontroller-scale devices. Due to limitations of FAT it can't provide
  power-loss resilience, but it does allow easy interop with PCs.

- [chamelon] - A pure-OCaml implementation of (most of) littlefs, designed for
-  use with the MirageOS library operating system project. It is interoperable
-  with the reference implementation, with some caveats.
-
- [nim-littlefs] - A Nim wrapper and API for littlefs. Includes a fuse 
-  implementation based on [littlefs-fuse]
-
 [BSD-3-Clause]: https://spdx.org/licenses/BSD-3-Clause.html
-[littlefs-disk-img-viewer]: https://github.com/tniessen/littlefs-disk-img-viewer
 [littlefs-fuse]: https://github.com/geky/littlefs-fuse
 [FUSE]: https://github.com/libfuse/libfuse
 [littlefs-js]: https://github.com/geky/littlefs-js
 [littlefs-js-demo]:http://littlefs.geky.net/demo.html
+[littlefs-python]: https://pypi.org/project/littlefs-python/
+[littlefs2-rust]: https://crates.io/crates/littlefs2
+[nim-littlefs]: https://github.com/Graveflo/nim-littlefs
+[chamelon]: https://github.com/yomimono/chamelon
+[littlefs-disk-img-viewer]: https://github.com/tniessen/littlefs-disk-img-viewer
 [mklfs]: https://github.com/whitecatboard/Lua-RTOS-ESP32/tree/master/components/mklfs/src
-[Lua RTOS]: https://github.com/whitecatboard/Lua-RTOS-ESP32
+[mklittlefs]: https://github.com/earlephilhower/mklittlefs
+[pico-littlefs-usb]: https://github.com/oyama/pico-littlefs-usb
 [Mbed OS]: https://github.com/armmbed/mbed-os
 [LittleFileSystem]: https://os.mbed.com/docs/mbed-os/latest/apis/littlefilesystem.html
 [SPIFFS]: https://github.com/pellepl/spiffs
 [Dhara]: https://github.com/dlbeer/dhara
 [ChaN's FatFs]: http://elm-chan.org/fsw/ff/00index_e.html
-[littlefs-python]: https://pypi.org/project/littlefs-python/
-[littlefs2-rust]: https://crates.io/crates/littlefs2
-[chamelon]: https://github.com/yomimono/chamelon
-[nim-littlefs]: https://github.com/Graveflo/nim-littlefs
--- a/lfs.c
+++ b/lfs.c
@@ -282,6 +282,21 @@ static int lfs_bd_erase(lfs_t *lfs, lfs_block_t block) {


 /// Small type-level utilities ///
+
+// some operations on paths
+static inline lfs_size_t lfs_path_namelen(const char *path) {
+    return strcspn(path, "/");
+}
+
+static inline bool lfs_path_islast(const char *path) {
+    lfs_size_t namelen = lfs_path_namelen(path);
+    return path[namelen + strspn(path + namelen, "/")] == '\0';
+}
+
+static inline bool lfs_path_isdir(const char *path) {
+    return path[lfs_path_namelen(path)] != '\0';
+}
+
 // operations on block pairs
 static inline void lfs_pair_swap(lfs_block_t pair[2]) {
    lfs_block_t t = pair[0];
@@ -688,7 +703,7 @@ static int lfs_alloc(lfs_t *lfs, lfs_block_t *block) {
        if (lfs->lookahead.ckpoint <= 0) {
            LFS_ERROR("No more free space 0x%"PRIx32,
                    (lfs->lookahead.start + lfs->lookahead.next)
-                        % lfs->cfg->block_count);
+                        % lfs->block_count);
            return LFS_ERR_NOSPC;
        }

@@ -1461,32 +1476,46 @@ static int lfs_dir_find_match(void *data,
    return LFS_CMP_EQ;
 }

+// lfs_dir_find tries to set path and id even if file is not found
+//
+// returns:
+// - 0                  if file is found
+// - LFS_ERR_NOENT      if file or parent is not found
+// - LFS_ERR_NOTDIR     if parent is not a dir
 static lfs_stag_t lfs_dir_find(lfs_t *lfs, lfs_mdir_t *dir,
        const char **path, uint16_t *id) {
    // we reduce path to a single name if we can find it
    const char *name = *path;
-    if (id) {
-        *id = 0x3ff;
-    }

    // default to root dir
    lfs_stag_t tag = LFS_MKTAG(LFS_TYPE_DIR, 0x3ff, 0);
    dir->tail[0] = lfs->root[0];
    dir->tail[1] = lfs->root[1];

+    // empty paths are not allowed
+    if (*name == '\0') {
+        return LFS_ERR_INVAL;
+    }
+
    while (true) {
 nextname:
-        // skip slashes
-        name += strspn(name, "/");
+        // skip slashes if we're a directory
+        if (lfs_tag_type3(tag) == LFS_TYPE_DIR) {
+            name += strspn(name, "/");
+        }
        lfs_size_t namelen = strcspn(name, "/");

-        // skip '.' and root '..'
-        if ((namelen == 1 && memcmp(name, ".", 1) == 0) ||
-            (namelen == 2 && memcmp(name, "..", 2) == 0)) {
+        // skip '.'
+        if (namelen == 1 && memcmp(name, ".", 1) == 0) {
            name += namelen;
            goto nextname;
        }

+        // error on unmatched '..', trying to go above root?
+        if (namelen == 2 && memcmp(name, "..", 2) == 0) {
+            return LFS_ERR_INVAL;
+        }
+
        // skip if matched by '..' in name
        const char *suffix = name + namelen;
        lfs_size_t sufflen;
@@ -1498,7 +1527,9 @@ nextname:
                break;
            }

-            if (sufflen == 2 && memcmp(suffix, "..", 2) == 0) {
+            if (sufflen == 1 && memcmp(suffix, ".", 1) == 0) {
+                // noop
+            } else if (sufflen == 2 && memcmp(suffix, "..", 2) == 0) {
                depth -= 1;
                if (depth == 0) {
                    name = suffix + sufflen;
@@ -1512,14 +1543,14 @@ nextname:
        }

        // found path
-        if (name[0] == '\0') {
+        if (*name == '\0') {
            return tag;
        }

        // update what we've found so far
        *path = name;

-        // only continue if we hit a directory
+        // only continue if we're a directory
        if (lfs_tag_type3(tag) != LFS_TYPE_DIR) {
            return LFS_ERR_NOTDIR;
        }
@@ -1539,8 +1570,7 @@ nextname:
            tag = lfs_dir_fetchmatch(lfs, dir, dir->tail,
                    LFS_MKTAG(0x780, 0, 0),
                    LFS_MKTAG(LFS_TYPE_NAME, 0, namelen),
-                     // are we last name?
-                    (strchr(name, '/') == NULL) ? id : NULL,
+                    id,
                    lfs_dir_find_match, &(struct lfs_dir_find_match){
                        lfs, name, namelen});
            if (tag < 0) {
@@ -2603,12 +2633,12 @@ static int lfs_mkdir_(lfs_t *lfs, const char *path) {
    cwd.next = lfs->mlist;
    uint16_t id;
    err = lfs_dir_find(lfs, &cwd.m, &path, &id);
-    if (!(err == LFS_ERR_NOENT && id != 0x3ff)) {
+    if (!(err == LFS_ERR_NOENT && lfs_path_islast(path))) {
        return (err < 0) ? err : LFS_ERR_EXIST;
    }

    // check that name fits
-    lfs_size_t nlen = strlen(path);
+    lfs_size_t nlen = lfs_path_namelen(path);
    if (nlen > lfs->name_max) {
        return LFS_ERR_NAMETOOLONG;
    }
@@ -3057,7 +3087,7 @@ static int lfs_file_opencfg_(lfs_t *lfs, lfs_file_t *file,

    // allocate entry for file if it doesn't exist
    lfs_stag_t tag = lfs_dir_find(lfs, &file->m, &path, &file->id);
-    if (tag < 0 && !(tag == LFS_ERR_NOENT && file->id != 0x3ff)) {
+    if (tag < 0 && !(tag == LFS_ERR_NOENT && lfs_path_islast(path))) {
        err = tag;
        goto cleanup;
    }
@@ -3077,8 +3107,14 @@ static int lfs_file_opencfg_(lfs_t *lfs, lfs_file_t *file,
            goto cleanup;
        }

+        // don't allow trailing slashes
+        if (lfs_path_isdir(path)) {
+            err = LFS_ERR_NOTDIR;
+            goto cleanup;
+        }
+
        // check that name fits
-        lfs_size_t nlen = strlen(path);
+        lfs_size_t nlen = lfs_path_namelen(path);
        if (nlen > lfs->name_max) {
            err = LFS_ERR_NAMETOOLONG;
            goto cleanup;
@@ -3842,6 +3878,12 @@ static int lfs_stat_(lfs_t *lfs, const char *path, struct lfs_info *info) {
        return (int)tag;
    }

+    // only allow trailing slashes on dirs
+    if (strchr(path, '/') != NULL
+            && lfs_tag_type3(tag) != LFS_TYPE_DIR) {
+        return LFS_ERR_NOTDIR;
+    }
+
    return lfs_dir_getinfo(lfs, &cwd, lfs_tag_id(tag), info);
 }

@@ -3944,7 +3986,7 @@ static int lfs_rename_(lfs_t *lfs, const char *oldpath, const char *newpath) {
    uint16_t newid;
    lfs_stag_t prevtag = lfs_dir_find(lfs, &newcwd, &newpath, &newid);
    if ((prevtag < 0 || lfs_tag_id(prevtag) == 0x3ff) &&
-            !(prevtag == LFS_ERR_NOENT && newid != 0x3ff)) {
+            !(prevtag == LFS_ERR_NOENT && lfs_path_islast(newpath))) {
        return (prevtag < 0) ? (int)prevtag : LFS_ERR_INVAL;
    }

@@ -3955,8 +3997,14 @@ static int lfs_rename_(lfs_t *lfs, const char *oldpath, const char *newpath) {
    struct lfs_mlist prevdir;
    prevdir.next = lfs->mlist;
    if (prevtag == LFS_ERR_NOENT) {
+        // if we're a file, don't allow trailing slashes
+        if (lfs_path_isdir(newpath)
+                && lfs_tag_type3(oldtag) != LFS_TYPE_DIR) {
+            return LFS_ERR_NOTDIR;
+        }
+
        // check that name fits
-        lfs_size_t nlen = strlen(newpath);
+        lfs_size_t nlen = lfs_path_namelen(newpath);
        if (nlen > lfs->name_max) {
            return LFS_ERR_NAMETOOLONG;
        }
@@ -4016,7 +4064,8 @@ static int lfs_rename_(lfs_t *lfs, const char *oldpath, const char *newpath) {
            {LFS_MKTAG_IF(prevtag != LFS_ERR_NOENT,
                LFS_TYPE_DELETE, newid, 0), NULL},
            {LFS_MKTAG(LFS_TYPE_CREATE, newid, 0), NULL},
-            {LFS_MKTAG(lfs_tag_type3(oldtag), newid, strlen(newpath)), newpath},
+            {LFS_MKTAG(lfs_tag_type3(oldtag),
+                newid, lfs_path_namelen(newpath)), newpath},
            {LFS_MKTAG(LFS_FROM_MOVE, newid, lfs_tag_id(oldtag)), &oldcwd},
            {LFS_MKTAG_IF(samepair,
                LFS_TYPE_DELETE, newoldid, 0), NULL}));
--- a/lfs.h
+++ b/lfs.h
@@ -59,7 +59,8 @@ typedef uint32_t lfs_block_t;
 #endif

 // Maximum size of custom attributes in bytes, may be redefined, but there is
-// no real benefit to using a smaller LFS_ATTR_MAX. Limited to <= 1022.
+// no real benefit to using a smaller LFS_ATTR_MAX. Limited to <= 1022. Stored
+// in superblock and must be respected by other littlefs drivers.
 #ifndef LFS_ATTR_MAX
 #define LFS_ATTR_MAX 1022
 #endif
@@ -203,7 +204,8 @@ struct lfs_config {
    // program sizes.
    lfs_size_t block_size;

-    // Number of erasable blocks on the device.
+    // Number of erasable blocks on the device. Defaults to block_count stored
+    // on disk when zero.
    lfs_size_t block_count;

    // Number of erase cycles before littlefs evicts metadata logs and moves
@@ -252,18 +254,18 @@ struct lfs_config {

    // Optional upper limit on length of file names in bytes. No downside for
    // larger names except the size of the info struct which is controlled by
-    // the LFS_NAME_MAX define. Defaults to LFS_NAME_MAX when zero. Stored in
-    // superblock and must be respected by other littlefs drivers.
+    // the LFS_NAME_MAX define. Defaults to LFS_NAME_MAX or name_max stored on
+    // disk when zero.
    lfs_size_t name_max;

    // Optional upper limit on files in bytes. No downside for larger files
-    // but must be <= LFS_FILE_MAX. Defaults to LFS_FILE_MAX when zero. Stored
-    // in superblock and must be respected by other littlefs drivers.
+    // but must be <= LFS_FILE_MAX. Defaults to LFS_FILE_MAX or file_max stored
+    // on disk when zero.
    lfs_size_t file_max;

    // Optional upper limit on custom attributes in bytes. No downside for
    // larger attributes size but must be <= LFS_ATTR_MAX. Defaults to
-    // LFS_ATTR_MAX when zero.
+    // LFS_ATTR_MAX or attr_max stored on disk when zero.
    lfs_size_t attr_max;

    // Optional upper limit on total space given to metadata pairs in bytes. On
--- a/tests/test_alloc.toml
+++ b/tests/test_alloc.toml
@@ -8,17 +8,22 @@ defines.FILES = 3
 defines.SIZE = '(((BLOCK_SIZE-8)*(BLOCK_COUNT-6)) / FILES)'
 defines.GC = [false, true]
 defines.COMPACT_THRESH = ['-1', '0', 'BLOCK_SIZE/2']
+defines.INFER_BC = [false, true]
 code = '''
    const char *names[] = {"bacon", "eggs", "pancakes"};
    lfs_file_t files[FILES];

    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
-    lfs_mount(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }
+    lfs_mount(&lfs, &cfg_) => 0;
    lfs_mkdir(&lfs, "breakfast") => 0;
    lfs_unmount(&lfs) => 0;

-    lfs_mount(&lfs, cfg) => 0;
+    lfs_mount(&lfs, &cfg_) => 0;
    for (int n = 0; n < FILES; n++) {
        char path[1024];
        sprintf(path, "breakfast/%s", names[n]);
@@ -39,7 +44,7 @@ code = '''
    }
    lfs_unmount(&lfs) => 0;

-    lfs_mount(&lfs, cfg) => 0;
+    lfs_mount(&lfs, &cfg_) => 0;
    for (int n = 0; n < FILES; n++) {
        char path[1024];
        sprintf(path, "breakfast/%s", names[n]);
@@ -62,17 +67,22 @@ defines.FILES = 3
 defines.SIZE = '(((BLOCK_SIZE-8)*(BLOCK_COUNT-6)) / FILES)'
 defines.GC = [false, true]
 defines.COMPACT_THRESH = ['-1', '0', 'BLOCK_SIZE/2']
+defines.INFER_BC = [false, true]
 code = '''
    const char *names[] = {"bacon", "eggs", "pancakes"};

    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
-    lfs_mount(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }
+    lfs_mount(&lfs, &cfg_) => 0;
    lfs_mkdir(&lfs, "breakfast") => 0;
    lfs_unmount(&lfs) => 0;

    for (int n = 0; n < FILES; n++) {
-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        char path[1024];
        sprintf(path, "breakfast/%s", names[n]);
        lfs_file_t file;
@@ -91,7 +101,7 @@ code = '''
        lfs_unmount(&lfs) => 0;
    }

-    lfs_mount(&lfs, cfg) => 0;
+    lfs_mount(&lfs, &cfg_) => 0;
    for (int n = 0; n < FILES; n++) {
        char path[1024];
        sprintf(path, "breakfast/%s", names[n]);
@@ -113,19 +123,24 @@ code = '''
 defines.FILES = 3
 defines.SIZE = '(((BLOCK_SIZE-8)*(BLOCK_COUNT-6)) / FILES)'
 defines.CYCLES = [1, 10]
+defines.INFER_BC = [false, true]
 code = '''
    const char *names[] = {"bacon", "eggs", "pancakes"};
    lfs_file_t files[FILES];

    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }

    for (int c = 0; c < CYCLES; c++) {
-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        lfs_mkdir(&lfs, "breakfast") => 0;
        lfs_unmount(&lfs) => 0;

-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        for (int n = 0; n < FILES; n++) {
            char path[1024];
            sprintf(path, "breakfast/%s", names[n]);
@@ -143,7 +158,7 @@ code = '''
        }
        lfs_unmount(&lfs) => 0;

-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        for (int n = 0; n < FILES; n++) {
            char path[1024];
            sprintf(path, "breakfast/%s", names[n]);
@@ -159,7 +174,7 @@ code = '''
        }
        lfs_unmount(&lfs) => 0;

-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        for (int n = 0; n < FILES; n++) {
            char path[1024];
            sprintf(path, "breakfast/%s", names[n]);
@@ -175,19 +190,24 @@ code = '''
 defines.FILES = 3
 defines.SIZE = '(((BLOCK_SIZE-8)*(BLOCK_COUNT-6)) / FILES)'
 defines.CYCLES = [1, 10]
+defines.INFER_BC = [false, true]
 code = '''
    const char *names[] = {"bacon", "eggs", "pancakes"};

    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }

    for (int c = 0; c < CYCLES; c++) {
-        lfs_mount(&lfs, cfg) => 0;
+        lfs_mount(&lfs, &cfg_) => 0;
        lfs_mkdir(&lfs, "breakfast") => 0;
        lfs_unmount(&lfs) => 0;

        for (int n = 0; n < FILES; n++) {
-            lfs_mount(&lfs, cfg) => 0;
+            lfs_mount(&lfs, &cfg_) => 0;
            char path[1024];
            sprintf(path, "breakfast/%s", names[n]);
            lfs_file_t file;
@@ -232,10 +252,15 @@ code = '''

 # exhaustion test
 [cases.test_alloc_exhaustion]
+defines.INFER_BC = [false, true]
 code = '''
    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
-    lfs_mount(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }
+    lfs_mount(&lfs, &cfg_) => 0;
    lfs_file_t file;
    lfs_file_open(&lfs, &file, "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
    size_t size = strlen("exhaustion");
@@ -263,7 +288,7 @@ code = '''
    lfs_file_close(&lfs, &file) => 0;
    lfs_unmount(&lfs) => 0;

-    lfs_mount(&lfs, cfg) => 0;
+    lfs_mount(&lfs, &cfg_) => 0;
    lfs_file_open(&lfs, &file, "exhaustion", LFS_O_RDONLY);
    size = strlen("exhaustion");
    lfs_file_size(&lfs, &file) => size;
@@ -276,10 +301,15 @@ code = '''
 # exhaustion wraparound test
 [cases.test_alloc_exhaustion_wraparound]
 defines.SIZE = '(((BLOCK_SIZE-8)*(BLOCK_COUNT-4)) / 3)'
+defines.INFER_BC = [false, true]
 code = '''
    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
-    lfs_mount(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }
+    lfs_mount(&lfs, &cfg_) => 0;

    lfs_file_t file;
    lfs_file_open(&lfs, &file, "padding", LFS_O_WRONLY | LFS_O_CREAT);
@@ -317,7 +347,7 @@ code = '''
    lfs_file_close(&lfs, &file) => 0;
    lfs_unmount(&lfs) => 0;

-    lfs_mount(&lfs, cfg) => 0;
+    lfs_mount(&lfs, &cfg_) => 0;
    lfs_file_open(&lfs, &file, "exhaustion", LFS_O_RDONLY);
    size = strlen("exhaustion");
    lfs_file_size(&lfs, &file) => size;
@@ -330,10 +360,15 @@ code = '''

 # dir exhaustion test
 [cases.test_alloc_dir_exhaustion]
+defines.INFER_BC = [false, true]
 code = '''
    lfs_t lfs;
    lfs_format(&lfs, cfg) => 0;
-    lfs_mount(&lfs, cfg) => 0;
+    struct lfs_config cfg_ = *cfg;
+    if (INFER_BC) {
+        cfg_.block_count = 0;
+    }
+    lfs_mount(&lfs, &cfg_) => 0;

    // find out max file size
    lfs_mkdir(&lfs, "exhaustiondir") => 0;
--- a/tests/test_paths.toml
+++ b/tests/test_paths.toml
Author	SHA1	Message	Date
Christopher Haster	999ef6656f	paths: Changed CREAT with a trailing slash to return NOTDIR - before: lfs_file_open("missing/") => LFS_ERR_ISDIR - after: lfs_file_open("missing/") => LFS_ERR_NOTDIR As noted by bmcdonnell-fb, returning LFS_ERR_ISDIR here was inconsistent with the case where the file exists: case before after lfs_file_open("dir_a") => LFS_ERR_ISDIR LFS_ERR_ISDIR lfs_file_open("dir_a/") => LFS_ERR_ISDIR LFS_ERR_ISDIR lfs_file_open("reg_a/") => LFS_ERR_NOTDIR LFS_ERR_NOTDIR lfs_file_open("missing_a/") => LFS_ERR_ISDIR LFS_ERR_NOTDIR Note this is consistent with the behavior of lfs_stat: lfs_file_open("reg_a/") => LFS_ERR_NOTDIR lfs_stat("reg_a/") => LFS_ERR_NOTDIR And the only other function that can "create" files, lfs_rename: lfs_file_open("missing_a/") => LFS_ERR_NOTDIR lfs_rename("reg_a", "missing_a/") => LFS_ERR_NOTDIR There is some ongoing discussion about if these should return NOTDIR, ISDIR, or INVAL, but this is at least an improvement over the rename/open mismatch.	2024-11-25 15:40:44 -06:00
Christopher Haster	b735c8fd7f	paths: Added tests over NOENT + trailing slash/dot - test_paths_noent_trailing_slashes - test_paths_noent_trailing_dots - test_paths_noent_trailing_dotdots These managed to slip through our path testing but should be tested, if anything just to know exactly what errors these return.	2024-11-25 15:40:15 -06:00
Christopher Haster	30947054d4	paths: Extended tests to cover open with CREAT/EXCL These flags change the behavior of open quite significantly. It's useful to cover these in our path tests so the behavior is locked down.	2024-11-25 15:40:15 -06:00
Christopher Haster	80ca1ea300	paths: Reject empty paths Before this, the empty path ("") was treated as an alias for the root. This was unintentional and just a side-effect of how the path parser worked. Now, the empty path should always result in LFS_ERR_INVAL: - before: lfs_stat("") => 0 - after: lfs_stat("") => LFS_ERR_INVAL	2024-11-25 15:40:15 -06:00
Christopher Haster	815f0d85a5	paths: Fixed dots followed by dotdots Unlike normal files, dots (".") should not change the depth when attempting to skip dotdot ("..") entries. A weird nuance in the path parser, but at least it had a relatively easy fix. Added test_paths_dot_dotdots to prevent a regression.	2024-11-25 15:40:15 -06:00
Christopher Haster	dc92dec6d3	paths: Reject dotdots above root This changes the behavior of paths that attempt to navigate above root to now return LFS_ERR_INVAL: - before: lfs_stat("/../a") => 0 - after: lfs_stat("/../a") => LFS_ERR_INVAL This is a bit of an opinionated change while making other path resolution tweaks. In terms of POSIX-compatibility, it's a bit unclear exactly what dotdots above the root should do. POSIX notes: > As a special case, in the root directory, dot-dot may refer to the > root directory itself. But the word choice of "may" implies it is up to the implementation. I originally implement this as a root-loop simply because that is what my Linux machine does, but I now think that's not the best option. Since we're making other path-related tweaks, we might as well try to adopt behavior that is, in my opinion, safer and less... weird... This should also help make paths more consistent with future theoretical openat-list APIs, where saturating at the current directory is sort of the least expected behavior.	2024-11-25 15:40:07 -06:00
Christopher Haster	a6035071be	paths: Fixed/doc trailing slash/dot POSIX incompatibilities - lfs_mkdir now accepts trailing slashes: - before: lfs_mkdir("a/") => LFS_ERR_NOENT - after: lfs_mkdir("a/") => 0 - lfs_stat, lfs_getattr, etc, now reject trailing slashes if the file is not a directory: - before: lfs_stat("reg_a/") => 0 - after: lfs_stat("reg_a/") => LFS_ERR_NOTDIR Note trailing slashes are accepted if the file is a directory: - before: lfs_stat("dir_a/") => 0 - after: lfs_stat("dir_a/") => 0 - lfs_file_open now returns LFS_ERR_NOTDIR if the file exists but the path contains trailing slashes: - before: lfs_file_open("reg_a/") => LFS_ERR_NOENT - after: lfs_file_open("reg_a/") => LFS_ERR_NOTDIR To make these work, the internal lfs_dir_find API required some interesting changes: - lfs_dir_find no longer sets id=0x3ff on not finding a parent entry in the path. Instead, lfs_path_islast can be used to determine if the modified path references a parent entry or child entry based on the remainder of the path string. Note this is only necessary for functions that create new entries (lfs_mkdir, lfs_rename, lfs_file_open). - Trailing slashes mean we can no longer rely on the modified path being NULL-terminated. lfs_path_namelen provides an alternative to strlen that stops at slash or NULL. - lfs_path_isdir also tells you if the modified path must reference a dir (contains trailing slashes). I considered handling this entirely in lfs_dir_find, but the behavior of entry-creating functions is too nuanced. At least lfs_dir_find returns LFS_ERR_NOTDIR if the file exists on disk. Like strlen, lfs_path_namelen/islast/isdir are all O(n) where n is the name length. This isn't great, but if you're using filenames large enough for this to actually matter... uh... open an issue on GitHub and we might improve this in the future. --- There are a couple POSIX incompatibilities that I think are not worth fixing: - Root modifications return EINVAL instead of EBUSY: - littlefs: remove("/") => EINVAL - POSIX: remove("/") => EBUSY Reason: This would be the only use of EBUSY in the system. - We accept modifications of directories with trailing dots: - littlefs: remove("a/.") => 0 - POSIX: remove("a/.") => EBUSY Reason: Not worth implementing. - We do not check for existence of directories followed by dotdots: - littlefs: stat("a/missing/..") => 0 - POSIX: stat("a/missing/..") => ENOENT Reason: Difficult to implement non-recursively. - We accept modifications of directories with trailing dotdots: - littlefs: rename("a/b/..", "c") => 0 - POSIX: rename("a/b/..", "c") => EBUSY Reason: Not worth implementing. These are at least now documented in tests/test_paths.toml, which isn't the greatest location, but it's at least something until a better document is created. Note that these don't really belong in SPEC.md because path parsing is a function of the driver and has no impact on disk.	2024-11-25 15:39:29 -06:00
Christopher Haster	232e736aae	paths: Added trailing slashes and dots tests As expected these are failing and will need some work to pass. The issue with lfs_file_open allowing trailing slashes was found by rob-zeno, and the issue with lfs_mkdir disallowing trailing slashes was found by XinStellaris, PoppaChubby, pavel-kirienko, inf265, Xywzel, steverpalmer, and likely others.	2024-11-23 19:03:36 -06:00
Christopher Haster	0de0389c6f	paths: Reworked test_paths to cover more corner cases This should be a superset of the previous test_paths test suite, while covering a couple more things (more APIs, more path synonyms, utf8, non-printable ascii, non-utf8, etc). Not yet tested are some corner cases with known bugs, mainly around trailing slashes.	2024-11-23 18:20:06 -06:00
Christopher Haster	b78afe2518	Merge pull request #1026 from yamt/update-gh-actions Update github actions to the latest versions	2024-09-24 12:25:04 -05:00
Christopher Haster	798073c2a7	gha: Dropped minor/patch version pinning of actions With GitHub forcibly deprecating old versions of actions, pinning the minor/patch version is more likely to cause breakage than not.	2024-09-20 16:05:15 -05:00
Christopher Haster	7db9e1663a	gha: Switched to standard da for cross-workflow downloads Looks like cross-workflow downloads has finally been added to the standard download-artifact action, so we might as well switch to it to reduce dependencies. dawidd6's version was also missing the merge-multiple feature which is necessary to work around breaking changes in download-artifact's v4 bump. Weirdly it needs GITHUB_TOKEN for some reason? Not sure why this couldn't be implicit.	2024-09-20 16:05:12 -05:00
Christopher Haster	2c4b262c35	gha: Merge artifacts on download Turns out major versions break things. Old behavior: Artifacts with same name are merged New behavior: Artifacts with same name error Using a pattern and merging on download should fix this at least on the job-side. Though I do wonder if we'll start running into artifact limit issues with the new way artifacts are handled...	2024-09-20 16:04:35 -05:00
YAMAMOTO Takashi	72a4b57f4e	gha: Make the artifact names unique	2024-09-19 17:26:49 -05:00
YAMAMOTO Takashi	6e7269890a	gha: Update github actions to the latest versions	2024-09-19 17:18:15 -05:00
Christopher Haster	d01280e649	Merge pull request #968 from littlefs-project/link-pico-littlefs-usb Add links to pico-littlefs-usb (FAT12 emulation) and mklittlefs	2024-04-29 16:21:49 -05:00
Christopher Haster	6e52140d51	Merge pull request #959 from littlefs-project/fix-expanded-magic Duplicate the superblock entry during superblock expansion, fix missing magic	2024-04-29 14:26:38 -05:00
Christopher Haster	0bbb8bc88b	Reorganized external project links a bit These were grouped up a bit better at one point, but that sort of drifted as new project were added: 1. Official repos (mainly littlefs-fuse) 2. Non-C reimplementations/wrappers 3. Utilities 4. Non-littlefs related projects Eventually, maybe when these move out of the README.md, these categories should probably be actually codified as headers or something.	2024-04-17 13:46:33 -05:00
Christopher Haster	78082336e7	Added a link to mklittlefs Implemented by earlephilhower, mklittlefs is a command line interface that seems to be used by the ESP8266 and RP2040 ecosystems. It deserves a mention. Also tweaked mklfs's description a bit.	2024-04-17 13:39:11 -05:00
Christopher Haster	8336ecd203	Added a link to pico-littlefs-usb (FAT12 emulation) Implemented by oyama, pico-littlefs-usb provides an easy interface to littlefs by emulating a FAT12 filesystem over USB. There are some tradeoffs to this, but being able to mount a littlefs device without installing additional drivers is very nice. Maybe in the future devices could provide both a FAT and raw endpoint for easy/advanced filesystem access.	2024-04-17 13:09:04 -05:00
Christopher Haster	68d28b5114	Merge pull request #966 from BrianPugh/fix-divide-by-zero-full-filesystem Fix DivideByZero exception when filesystem is completely full.	2024-04-17 12:38:22 -05:00
Christopher Haster	1bc14933b7	Tweaked on-disk config comments for consistency - Prefer "defaults to blablabla when zero" to hint that this is the default state when both explicitly set to zero and implicitly set to zero thanks to C's initializers. - Prefer "disk" when referencing something stored "on disk". Other terms can quickly get ambiguous. Except maybe "block device"...	2024-04-17 00:16:20 -05:00
Christopher Haster	01b6a47ea8	Extended test_alloc to test inferred block_count The block allocator is an area where inferred block counts (when cfg.block_count=0) are more likely to cause problems. As is shown by the recent divide-by-zero-exhaustion issue.	2024-04-17 00:04:56 -05:00
Brian Pugh	749a45650f	Fix DivideByZero exception when filesystem is completely full.	2024-04-16 20:32:12 -07:00