Added file config structure and lfs_file_opencfg

The optional config structure options up the possibility of adding
file-level configuration in a backwards compatible manner.

Also bumped minor version to v1.5

.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

Makefile

@@ -1,4 +1,7 @@
-TARGET = lfs
+TARGET = lfs.a
+ifneq ($(wildcard test.c main.c),)
+override TARGET = lfs
+endif
 
 CC ?= gcc
 AR ?= ar
@@ -22,7 +25,7 @@ ifdef WORD
 override CFLAGS += -m$(WORD)
 endif
 override CFLAGS += -I.
-override CFLAGS += -std=c99 -Wall -pedantic
+override CFLAGS += -std=c99 -Wall -pedantic -Wshadow -Wunused-parameter
 
 
 all: $(TARGET)
@@ -35,7 +38,9 @@ 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 +49,7 @@ endif
 
 -include $(DEP)
 
-$(TARGET): $(OBJ)
+lfs: $(OBJ)
 	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@
 
 %.a: $(OBJ)

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
@@ -85,7 +86,7 @@ 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 +125,7 @@ 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 +172,7 @@ 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 +240,3 @@ 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;
         }
 
@@ -465,7 +481,8 @@ 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 +605,16 @@ 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 +627,7 @@ 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 +854,7 @@ 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 +1232,10 @@ 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 +1282,9 @@ static int lfs_ctz_traverse(lfs_t *lfs,
 
 
 /// Top level file operations ///
-int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
-        const char *path, int flags) {
+int lfs_file_opencfg(lfs_t *lfs, lfs_file_t *file,
+        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 +1324,7 @@ 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 +1343,9 @@ 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 +1363,9 @@ int lfs_file_open(lfs_t *lfs, lfs_file_t *file,
         }
     }
 
+    // zero to avoid information leak
+    lfs_cache_zero(lfs, &file->cache);
+
     // add to list of files
     file->next = lfs->files;
     lfs->files = file;
@@ -1348,6 +1373,11 @@ 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 +1390,7 @@ 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 +1399,7 @@ 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 +1439,7 @@ 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 +1448,7 @@ 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 +1463,7 @@ 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 +1481,8 @@ 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->rcache.block = 0xffffffff;
+                lfs_cache_drop(lfs, &orig.cache);
+                lfs_cache_drop(lfs, &lfs->rcache);
             }
         }
 
@@ -1630,7 +1660,7 @@ 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
@@ -1981,7 +2011,6 @@ 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 {
@@ -1992,7 +2021,6 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
     }
 
     // setup program cache
-    lfs->pcache.block = 0xffffffff;
     if (lfs->cfg->prog_buffer) {
         lfs->pcache.buffer = lfs->cfg->prog_buffer;
     } else {
@@ -2002,6 +2030,10 @@ static int lfs_init(lfs_t *lfs, const struct lfs_config *cfg) {
         }
     }
 
+    // zero to avoid information leaks
+    lfs_cache_zero(lfs, &lfs->rcache);
+    lfs_cache_zero(lfs, &lfs->pcache);
+
     // setup lookahead, round down to nearest 32-bits
     LFS_ASSERT(lfs->cfg->lookahead % 32 == 0);
     LFS_ASSERT(lfs->cfg->lookahead > 0);
@@ -2378,7 +2410,8 @@ 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];
         }
@@ -2434,7 +2467,7 @@ 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];
@@ -2450,7 +2483,7 @@ int lfs_deorphan(lfs_t *lfs) {
 
             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];
@@ -2485,14 +2518,14 @@ 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);
@@ -2508,4 +2541,3 @@ int lfs_deorphan(lfs_t *lfs) {
 
     return 0;
 }
-

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 0x00010005
 #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
-// 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
@@ -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_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;