/LITTLEFS

LittleFS library for arduino-esp32

Primary LanguageCGNU General Public License v2.0GPL-2.0

LittleFS_esp32

Notice: The Library is been integrated to Arduino esp32 core idf-release/v4.2 branch for future major core release. On built-in library, #define tweaks below will be unavailable.

LittleFS library for arduino-esp32

Installation

  • Use Arduino Library Manager
  • Or download / use git to have latest repository of LITTLEFS added to Arduino IDE /libraries folder
    (File > Preferences > Sketchbook location).
  • See #define CONFIG_LITTLEFS_FOR_IDF_3_2 in esp_littlefs.c.
    Now it is defined / undefined automatically by detecting the IDF version and core version. When defined, the library works with old and new IDFs 3.2 - 4.x but file timestamp feature is removed. See LITTLEFS_time example.
  • See #define CONFIG_LITTLEFS_SPIFFS_COMPAT in esp_littlefs.c.
    When set to 1, folders are recursively created or deleted if empty on creating/deleting a new file like SPIFFS. Default is 0.
  • The other #define CONFIG_LITTLEFS_xxxxx are set to optimal default values.
    Read here and here if you want to modify.
  • For low-level default error reporting modifications, see the defines at beginning of the lfs.c here.

Usage

#define USE_LittleFS

#include <FS.h>
#ifdef USE_LittleFS
  #define SPIFFS LITTLEFS
  #include <LITTLEFS.h> 
#else
  #include <SPIFFS.h>
#endif 
  • Note, this may not work if your sketch uses other libraries that use SPIFFS themselves.
  • See also esp_partition.h . LITTLEFS re-uses same type and subtype as SPIFFS

Differences with SPIFFS

  • LittleFS has folders, you need to iterate files in folders unless you set #define CONFIG_LITTLEFS_SPIFFS_COMPAT 1
  • At root a "/folder" = "folder"
  • Requires a label for mount point, NULL will not work. Recommended is to use default LITTLEFS.begin()
  • maxOpenFiles parameter is unused, kept for compatibility
  • LITTLEFS.mkdir(path) and LITTLEFS.rmdir(path) are available
  • file.seek() behaves like on FFat see more details
  • file.write() and file.print() when partition space is ending may return different than really written bytes (on other FS is also inconsistent).
  • Speed comparison based on LittleFS_test.ino sketch (for a file 1048576 bytes):
Filesystem Read time [ms] Write time [ms]
FAT 276 14493
LITTLEFS 446* 16387
SPIFFS 767 65622

*The read speed improved by changing #define CONFIG_LITTLEFS_CACHE_SIZE from 128 to 512

Arduino ESP32 LittleFS filesystem upload tool

PlatformIO

  • See LITTLEFS_PlatformIO example here
    ( based on notes below from BlueAndi )

  • Add to platformio.ini: extra_scripts = replace_fs.py

  • Add replace_fs.py to project root directory (where platformio.ini is located):

Import("env")
print("Replace MKSPIFFSTOOL with mklittlefs.exe")
env.Replace (MKSPIFFSTOOL = "mklittlefs.exe")
  • Add mklittlefs.exe to project root directory as well.

Credits and license

To Do

  • Submit to be added to Arduino Library Manager
  • Optional drop-in compatibility with SPIFFS' lack of folders, similar to esp8266' way - implemented as a choice by a #define
  • Retire this library when released by esp32 Arduino core
  • Cleanup examples