Added handling for corrupt as initial state of blocks

Before this, littlefs incorrectly assumed corrupt blocks were only the result
of our own modification. This would be fine for most cases of freshly
erased storage, but for storage with block-level ECC this wasn't always
true.

Fortunately, it's quite easy for littlefs to handle this case correctly,
as long as corrupt storage always reports that it is corrupt, which for
most forms of ECC is the case unless we perform a write on the storage.

found by rojer

.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
@@ -35,7 +35,7 @@ script:
     if [ "$TRAVIS_TEST_RESULT" -eq 0 ]
     then
         CURR=$(tail -n1 sizes | awk '{print $1}')
-        PREV=$(curl https://api.github.com/repos/$TRAVIS_REPO_SLUG/status/master \
+        PREV=$(curl -u $GEKY_BOT_STATUSES https://api.github.com/repos/$TRAVIS_REPO_SLUG/status/master \
             | jq -re "select(.sha != \"$TRAVIS_COMMIT\")
                 | .statuses[] | select(.context == \"$STAGE/$NAME\").description
                 | capture(\"code size is (?<size>[0-9]+)\").size" \
@@ -165,7 +165,8 @@ jobs:
                     \"name\": \"$LFS_VERSION\"
                 }"
             RELEASE=$(
-                curl -f https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases/tags/$LFS_VERSION
+                curl -f -u $GEKY_BOT_RELEASES \
+                    https://api.github.com/repos/$TRAVIS_REPO_SLUG/releases/tags/$LFS_VERSION
             )
             CHANGES=$(
                 git log --oneline $LFS_PREV_VERSION.. --grep='^Merge' --invert-grep

LICENSE.md

@@ -1,165 +1,36 @@
-Apache License
-Version 2.0, January 2004
-http://www.apache.org/licenses/
+Copyright (c) 2017, Arm Limited. All rights reserved.
 
-TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
 
-1. Definitions.
+-  Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+-  Redistributions in binary form must reproduce the above copyright notice, this
+   list of conditions and the following disclaimer in the documentation and/or
+   other materials provided with the distribution.
+-  Neither the name of ARM nor the names of its contributors may be used to
+   endorse or promote products derived from this software without specific prior
+   written permission.
 
-"License" shall mean the terms and conditions for use, reproduction, and
-distribution as defined by Sections 1 through 9 of this document.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+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.
 
-"Licensor" shall mean the copyright owner or entity authorized by the copyright
-owner that is granting the License.
+---
 
-"Legal Entity" shall mean the union of the acting entity and all other entities
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-indirect, to cause the direction or management of such entity, whether by
-contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the
-outstanding shares, or (iii) beneficial ownership of such entity.
+*Note*:
+Individual files contain the following tag instead of the full license text.
 
-"You" (or "Your") shall mean an individual or Legal Entity exercising
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-"Object" form shall mean any form resulting from mechanical transformation or
-translation of a Source form, including but not limited to compiled object code,
-generated documentation, and conversions to other media types.
+    SPDX-License-Identifier:    BSD-3-Clause
 
-"Work" shall mean the work of authorship, whether in Source or Object form, made
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-additional or different license terms and conditions for use, reproduction, or
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-5. Submission of Contributions.
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-Unless You explicitly state otherwise, any Contribution intentionally submitted
-for inclusion in the Work by You to the Licensor shall be under the terms and
-conditions of this License, without any additional terms or conditions.
-Notwithstanding the above, nothing herein shall supersede or modify the terms of
-any separate license agreement you may have executed with Licensor regarding
-such Contributions.
-
-6. Trademarks.
-
-This License does not grant permission to use the trade names, trademarks,
-service marks, or product names of the Licensor, except as required for
-reasonable and customary use in describing the origin of the Work and
-reproducing the content of the NOTICE file.
-
-7. Disclaimer of Warranty.
-
-Unless required by applicable law or agreed to in writing, Licensor provides the
-Work (and each Contributor provides its Contributions) on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied,
-including, without limitation, any warranties or conditions of TITLE,
-NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are
-solely responsible for determining the appropriateness of using or
-redistributing the Work and assume any risks associated with Your exercise of
-permissions under this License.
-
-8. Limitation of Liability.
-
-In no event and under no legal theory, whether in tort (including negligence),
-contract, or otherwise, unless required by applicable law (such as deliberate
-and grossly negligent acts) or agreed to in writing, shall any Contributor be
-liable to You for damages, including any direct, indirect, special, incidental,
-or consequential damages of any character arising as a result of this License or
-out of the use or inability to use the Work (including but not limited to
-damages for loss of goodwill, work stoppage, computer failure or malfunction, or
-any and all other commercial damages or losses), even if such Contributor has
-been advised of the possibility of such damages.
-
-9. Accepting Warranty or Additional Liability.
-
-While redistributing the Work or Derivative Works thereof, You may choose to
-offer, and charge a fee for, acceptance of support, warranty, indemnity, or
-other liability obligations and/or rights consistent with this License. However,
-in accepting such obligations, You may act only on Your own behalf and on Your
-sole responsibility, not on behalf of any other Contributor, and only if You
-agree to indemnify, defend, and hold each Contributor harmless for any liability
-incurred by, or claims asserted against, such Contributor by reason of your
-accepting any such warranty or additional liability.
+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
@@ -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)
@@ -33,9 +36,11 @@ size: $(OBJ)
 	$(SIZE) -t $^
 
 .SUFFIXES:
-test: test_format test_dirs test_files test_seek test_truncate test_parallel \
-	test_alloc test_paths test_orphan test_move test_corrupt
+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

@@ -1,19 +1,8 @@
 /*
  * Block device emulated on standard files
  *
- * Copyright (c) 2017 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Copyright (c) 2017, Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
  */
 #include "emubd/lfs_emubd.h"
 
@@ -27,6 +16,7 @@
 #include <unistd.h>
 #include <assert.h>
 #include <stdbool.h>
+#include <inttypes.h>
 
 
 // Block device emulated on existing filesystem
@@ -96,7 +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) {
@@ -135,7 +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) {
@@ -182,7 +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) {
@@ -250,4 +240,3 @@ int lfs_emubd_sync(const struct lfs_config *cfg) {
 
     return 0;
 }
-

emubd/lfs_emubd.h

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

@@ -1,19 +1,8 @@
 /*
  * The little filesystem
  *
- * Copyright (c) 2017 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Copyright (c) 2017, Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
  */
 #ifndef LFS_H
 #define LFS_H
@@ -21,6 +10,11 @@
 #include <stdint.h>
 #include <stdbool.h>
 
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
 
 /// Version info ///
 
@@ -34,7 +28,7 @@
 // Version of On-disk data structures
 // Major (top-nibble), incremented on backwards incompatible changes
 // Minor (bottom-nibble), incremented on feature additions
-#define LFS_DISK_VERSION 0x00010002
+#define LFS_DISK_VERSION 0x00010001
 #define LFS_DISK_VERSION_MAJOR (0xffff & (LFS_DISK_VERSION >> 16))
 #define LFS_DISK_VERSION_MINOR (0xffff & (LFS_DISK_VERSION >>  0))
 
@@ -50,78 +44,51 @@ typedef int32_t  lfs_soff_t;
 
 typedef uint32_t lfs_block_t;
 
-// Maximum inline file size in bytes. Large inline files require a larger
-// read and prog cache, but if a file can be inline it does not need its own
-// data block. LFS_ATTRS_MAX + LFS_INLINE_MAX must be <= 0xffff. Stored in
-// superblock and must be respected by other littlefs drivers.
-#ifndef LFS_INLINE_MAX
-#define LFS_INLINE_MAX 0x3ff
-#endif
-
-// Maximum size of all attributes per file in bytes, may be redefined but a
-// a smaller LFS_ATTRS_MAX has no benefit. LFS_ATTRS_MAX + LFS_INLINE_MAX
-// must be <= 0xffff. Stored in superblock and must be respected by other
-// littlefs drivers.
-#ifndef LFS_ATTRS_MAX
-#define LFS_ATTRS_MAX 0x3f
-#endif
-
-// Max name size in bytes, may be redefined to reduce the size of the
-// info struct. Stored in superblock and must be respected by other
-// littlefs drivers.
+// Max name size in bytes
 #ifndef LFS_NAME_MAX
-#define LFS_NAME_MAX 0xff
+#define LFS_NAME_MAX 255
 #endif
 
 // Possible error codes, these are negative to allow
 // valid positive return values
 enum lfs_error {
-    LFS_ERR_OK          = 0,    // No error
-    LFS_ERR_IO          = -5,   // Error during device operation
-    LFS_ERR_CORRUPT     = -52,  // Corrupted
-    LFS_ERR_NOENT       = -2,   // No directory entry
-    LFS_ERR_EXIST       = -17,  // Entry already exists
-    LFS_ERR_NOTDIR      = -20,  // Entry is not a dir
-    LFS_ERR_ISDIR       = -21,  // Entry is a dir
-    LFS_ERR_NOTEMPTY    = -39,  // Dir is not empty
-    LFS_ERR_BADF        = -9,   // Bad file number
-    LFS_ERR_INVAL       = -22,  // Invalid parameter
-    LFS_ERR_NOSPC       = -28,  // No space left on device
-    LFS_ERR_NOMEM       = -12,  // No more memory available
-    LFS_ERR_NAMETOOLONG = -36,  // File name too long
+    LFS_ERR_OK       = 0,    // No error
+    LFS_ERR_IO       = -5,   // Error during device operation
+    LFS_ERR_CORRUPT  = -52,  // Corrupted
+    LFS_ERR_NOENT    = -2,   // No directory entry
+    LFS_ERR_EXIST    = -17,  // Entry already exists
+    LFS_ERR_NOTDIR   = -20,  // Entry is not a dir
+    LFS_ERR_ISDIR    = -21,  // Entry is a dir
+    LFS_ERR_NOTEMPTY = -39,  // Dir is not empty
+    LFS_ERR_BADF     = -9,   // Bad file number
+    LFS_ERR_INVAL    = -22,  // Invalid parameter
+    LFS_ERR_NOSPC    = -28,  // No space left on device
+    LFS_ERR_NOMEM    = -12,  // No more memory available
 };
 
 // File types
 enum lfs_type {
-    // file type
-    LFS_TYPE_REG        = 0x01,
-    LFS_TYPE_DIR        = 0x02,
-    LFS_TYPE_SUPERBLOCK = 0x0e,
-
-    // on disk structure
-    LFS_STRUCT_CTZ      = 0x10,
-    LFS_STRUCT_DIR      = 0x20,
-    LFS_STRUCT_INLINE   = 0x30,
-    LFS_STRUCT_MOVED    = 0x80,
+    LFS_TYPE_REG        = 0x11,
+    LFS_TYPE_DIR        = 0x22,
+    LFS_TYPE_SUPERBLOCK = 0x2e,
 };
 
 // File open flags
 enum lfs_open_flags {
     // open flags
-    LFS_O_RDONLY = 1,         // Open a file as read only
-    LFS_O_WRONLY = 2,         // Open a file as write only
-    LFS_O_RDWR   = 3,         // Open a file as read and write
-    LFS_O_CREAT  = 0x0100,    // Create a file if it does not exist
-    LFS_O_EXCL   = 0x0200,    // Fail if a file already exists
-    LFS_O_TRUNC  = 0x0400,    // Truncate the existing file to zero size
-    LFS_O_APPEND = 0x0800,    // Move to end of file on every write
+    LFS_O_RDONLY = 1,        // Open a file as read only
+    LFS_O_WRONLY = 2,        // Open a file as write only
+    LFS_O_RDWR   = 3,        // Open a file as read and write
+    LFS_O_CREAT  = 0x0100,   // Create a file if it does not exist
+    LFS_O_EXCL   = 0x0200,   // Fail if a file already exists
+    LFS_O_TRUNC  = 0x0400,   // Truncate the existing file to zero size
+    LFS_O_APPEND = 0x0800,   // Move to end of file on every write
 
     // internally used flags
-    LFS_F_DIRTY   = 0x010000, // File does not match storage
-    LFS_F_WRITING = 0x020000, // File has been written since last flush
-    LFS_F_READING = 0x040000, // File has been read since last flush
-    LFS_F_ERRED   = 0x080000, // An error occured during write
-    LFS_F_INLINE  = 0x100000, // Currently inlined in directory entry
+    LFS_F_DIRTY   = 0x10000, // File does not match storage
+    LFS_F_WRITING = 0x20000, // File has been written since last flush
+    LFS_F_READING = 0x40000, // File has been read since last flush
+    LFS_F_ERRED   = 0x80000, // An error occured during write
 };
 
 // File seek flags
@@ -198,25 +165,6 @@ struct lfs_config {
     // Optional, statically allocated buffer for files. Must be program sized.
     // If enabled, only one file may be opened at a time.
     void *file_buffer;
-
-    // Optional upper limit on inlined files in bytes. Large inline files
-    // require a larger read and prog cache, but if a file can be inlined it
-    // does not need its own data block. Must be smaller than the read size
-    // and prog size. Defaults to min(LFS_INLINE_MAX, read_size) when zero.
-    // Stored in superblock and must be respected by other littlefs drivers.
-    lfs_size_t inline_size;
-
-    // Optional upper limit on attributes per file in bytes. No downside for
-    // larger attributes size but must be less than LFS_ATTRS_MAX. Defaults to
-    // LFS_ATTRS_MAX when zero.Stored in superblock and must be respected by
-    // other littlefs drivers.
-    lfs_size_t attrs_size;
-
-    // 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.
-    lfs_size_t name_size;
 };
 
 
@@ -236,7 +184,6 @@ struct lfs_info {
 /// littlefs data structures ///
 typedef struct lfs_entry {
     lfs_off_t off;
-    lfs_size_t size;
 
     struct lfs_disk_entry {
         uint8_t type;
@@ -268,7 +215,6 @@ typedef struct lfs_file {
     lfs_size_t size;
 
     uint32_t flags;
-    lfs_size_t inline_size;
     lfs_off_t pos;
     lfs_block_t block;
     lfs_off_t off;
@@ -291,23 +237,25 @@ typedef struct lfs_dir {
 } lfs_dir_t;
 
 typedef struct lfs_superblock {
+    lfs_off_t off;
+
     struct lfs_disk_superblock {
+        uint8_t type;
+        uint8_t elen;
+        uint8_t alen;
+        uint8_t nlen;
         lfs_block_t root[2];
-
-        lfs_size_t block_size;
-        lfs_size_t block_count;
+        uint32_t block_size;
+        uint32_t block_count;
         uint32_t version;
-
-        lfs_size_t inline_size;
-        lfs_size_t attrs_size;
-        lfs_size_t name_size;
+        char magic[8];
     } d;
 } lfs_superblock_t;
 
 typedef struct lfs_free {
-    lfs_block_t begin;
-    lfs_block_t size;
     lfs_block_t off;
+    lfs_block_t size;
+    lfs_block_t i;
     lfs_block_t ack;
     uint32_t *buffer;
 } lfs_free_t;
@@ -325,10 +273,6 @@ typedef struct lfs {
 
     lfs_free_t free;
     bool deorphaned;
-
-    lfs_size_t inline_size;
-    lfs_size_t attrs_size;
-    lfs_size_t name_size;
 } lfs_t;
 
 
@@ -370,10 +314,6 @@ int lfs_remove(lfs_t *lfs, const char *path);
 // If the destination exists, it must match the source in type.
 // If the destination is a directory, the directory must be empty.
 //
-// Note: If power loss occurs, it is possible that the file or directory
-// will exist in both the oldpath and newpath simultaneously after the
-// next mount.
-//
 // Returns a negative error code on failure.
 int lfs_rename(lfs_t *lfs, const char *oldpath, const char *newpath);
 
@@ -525,4 +465,8 @@ 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.c

@@ -1,19 +1,8 @@
 /*
  * lfs util functions
  *
- * Copyright (c) 2017 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Copyright (c) 2017, Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
  */
 #include "lfs_util.h"
 

lfs_util.h

@@ -1,19 +1,8 @@
 /*
  * lfs utility functions
  *
- * Copyright (c) 2017 ARM Limited
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * Copyright (c) 2017, Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
  */
 #ifndef LFS_UTIL_H
 #define LFS_UTIL_H
@@ -45,6 +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
@@ -169,6 +163,7 @@ static inline void *lfs_malloc(size_t size) {
 #ifndef LFS_NO_MALLOC
     return malloc(size);
 #else
+    (void)size;
     return NULL;
 #endif
 }
@@ -177,9 +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

@@ -274,12 +274,9 @@ TEST
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;
 
-    // create one block hole for half a directory
+    // create one block whole for half a directory
     lfs_file_open(&lfs, &file[0], "bump", LFS_O_WRONLY | LFS_O_CREAT) => 0;
-    for (lfs_size_t i = 0; i < cfg.block_size; i += 2) {
-        memcpy(&buffer[i], "hi", 2);
-    }
-    lfs_file_write(&lfs, &file[0], buffer, cfg.block_size) => cfg.block_size;
+    lfs_file_write(&lfs, &file[0], (void*)"hi", 2) => 2;
     lfs_file_close(&lfs, &file[0]) => 0;
 
     lfs_file_open(&lfs, &file[0], "exhaustion", LFS_O_WRONLY | LFS_O_CREAT);
@@ -298,10 +295,130 @@ tests/test.py << TEST
     lfs_mkdir(&lfs, "splitdir") => 0;
     lfs_file_open(&lfs, &file[0], "splitdir/bump",
             LFS_O_WRONLY | LFS_O_CREAT) => 0;
-    for (lfs_size_t i = 0; i < cfg.block_size; i += 2) {
-        memcpy(&buffer[i], "hi", 2);
+    lfs_file_write(&lfs, &file[0], buffer, size) => LFS_ERR_NOSPC;
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Outdated lookahead test ---"
+rm -rf blocks
+tests/test.py << TEST
+    lfs_format(&lfs, &cfg) => 0;
+
+    lfs_mount(&lfs, &cfg) => 0;
+
+    // fill completely with two files
+    lfs_file_open(&lfs, &file[0], "exhaustion1",
+            LFS_O_WRONLY | LFS_O_CREAT) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
     }
-    lfs_file_write(&lfs, &file[0], buffer, cfg.block_size) => LFS_ERR_NOSPC;
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    lfs_file_open(&lfs, &file[0], "exhaustion2",
+            LFS_O_WRONLY | LFS_O_CREAT) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4+1)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    // remount to force reset of lookahead
+    lfs_unmount(&lfs) => 0;
+
+    lfs_mount(&lfs, &cfg) => 0;
+
+    // rewrite one file
+    lfs_file_open(&lfs, &file[0], "exhaustion1",
+            LFS_O_WRONLY | LFS_O_TRUNC) => 0;
+    lfs_file_sync(&lfs, &file[0]) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    // rewrite second file, this requires lookahead does not
+    // use old population
+    lfs_file_open(&lfs, &file[0], "exhaustion2",
+            LFS_O_WRONLY | LFS_O_TRUNC) => 0;
+    lfs_file_sync(&lfs, &file[0]) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4+1)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+TEST
+
+echo "--- Outdated lookahead and split dir test ---"
+rm -rf blocks
+tests/test.py << TEST
+    lfs_format(&lfs, &cfg) => 0;
+
+    lfs_mount(&lfs, &cfg) => 0;
+
+    // fill completely with two files
+    lfs_file_open(&lfs, &file[0], "exhaustion1",
+            LFS_O_WRONLY | LFS_O_CREAT) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    lfs_file_open(&lfs, &file[0], "exhaustion2",
+            LFS_O_WRONLY | LFS_O_CREAT) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4+1)/2)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    // remount to force reset of lookahead
+    lfs_unmount(&lfs) => 0;
+
+    lfs_mount(&lfs, &cfg) => 0;
+
+    // rewrite one file with a hole of one block
+    lfs_file_open(&lfs, &file[0], "exhaustion1",
+            LFS_O_WRONLY | LFS_O_TRUNC) => 0;
+    lfs_file_sync(&lfs, &file[0]) => 0;
+    size = strlen("blahblahblahblah");
+    memcpy(buffer, "blahblahblahblah", size);
+    for (lfs_size_t i = 0;
+            i < ((cfg.block_count-4)/2 - 1)*(cfg.block_size-8);
+            i += size) {
+        lfs_file_write(&lfs, &file[0], buffer, size) => size;
+    }
+    lfs_file_close(&lfs, &file[0]) => 0;
+
+    // try to allocate a directory, should fail!
+    lfs_mkdir(&lfs, "split") => LFS_ERR_NOSPC;
+
+    // file should not fail
+    lfs_file_open(&lfs, &file[0], "notasplit",
+            LFS_O_WRONLY | LFS_O_CREAT) => 0;
+    lfs_file_write(&lfs, &file[0], "hi", 2) => 2;
     lfs_file_close(&lfs, &file[0]) => 0;
 
     lfs_unmount(&lfs) => 0;

tests/test_corrupt.sh

@@ -73,7 +73,7 @@ lfs_mktree
 lfs_chktree
 
 echo "--- Block corruption ---"
-for i in {2..33}
+for i in {0..33}
 do 
     rm -rf blocks
     mkdir blocks
@@ -83,12 +83,12 @@ do
 done
 
 echo "--- Block persistance ---"
-for i in {2..33}
+for i in {0..33}
 do 
     rm -rf blocks
     mkdir blocks
     lfs_mktree
-    chmod a-w blocks/$(printf '%x' $i) || true
+    chmod a-w blocks/$(printf '%x' $i)
     lfs_mktree
     lfs_chktree
 done

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_format.sh

@@ -30,10 +30,20 @@ echo "--- Invalid mount ---"
 tests/test.py << TEST
     lfs_format(&lfs, &cfg) => 0;
 TEST
-rm -f blocks/0 blocks/1
+rm blocks/0 blocks/1
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => LFS_ERR_CORRUPT;
 TEST
 
+echo "--- Valid corrupt mount ---"
+tests/test.py << TEST
+    lfs_format(&lfs, &cfg) => 0;
+TEST
+rm blocks/0
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
 echo "--- Results ---"
 tests/stats.py

tests/test_interspersed.sh

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

tests/test_paths.sh

@@ -90,6 +90,22 @@ tests/test.py << TEST
     lfs_unmount(&lfs) => 0;
 TEST
 
+echo "--- Trailing dot path tests ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_stat(&lfs, "tea/hottea/", &info) => 0;
+    strcmp(info.name, "hottea") => 0;
+    lfs_stat(&lfs, "tea/hottea/.", &info) => 0;
+    strcmp(info.name, "hottea") => 0;
+    lfs_stat(&lfs, "tea/hottea/./.", &info) => 0;
+    strcmp(info.name, "hottea") => 0;
+    lfs_stat(&lfs, "tea/hottea/..", &info) => 0;
+    strcmp(info.name, "tea") => 0;
+    lfs_stat(&lfs, "tea/hottea/../.", &info) => 0;
+    strcmp(info.name, "tea") => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
 echo "--- Root dot dot path tests ---"
 tests/test.py << TEST
     lfs_mount(&lfs, &cfg) => 0;

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;