⚠️ This repository has moved to: https://gitlab.com/mbitsnbites/mfat
MFAT is a minimal I/O library for FAT (File Allocation Table) volumes.
The library has been designed for embedded systems, and its small code and memory footprint makes it suitable for inclusion in firmware/ROM and/or small OS kernels.
- Works with any storage medium that supports random access block I/O (SD cards, hard drives, raw disk image files, etc).
- Supports both FAT16 and FAT32.
- Supports multiple partitions (both MBR and GPT partition tables are supported).
- Cached I/O (configurable cache size).
- Small memory footprint.
- No dynamic memory allocation (only static/BSS).
- Configurable to tune code and memory requirements.
- Completely dependency-free.
- Implemented in portable C99.
- Easy to integrate into your project (only two files are needed: mfat.h and mfat.c).
- Familiar and easy-to-use POSIX-like API.
- Liberal license (BSD-2-Clause).
The internal MFAT context is statically allocated, meaning:
- Only a single device may be mounted at any time.
- The API is not thread safe.
Also: MFAT is still work-in-progress.
- Writing is not supported yet.
- Long file names are not supported yet.
The API of this library is modelled after the POSIX.1-2017 file I/O C API:s.
These are the MFAT functions that are inspired by POSIX functions:
| MFAT function | POSIX prototype |
|---|---|
mfat_close() |
close() |
mfat_closedir() |
closedir() |
mfat_fdopendir() |
fdopendir() |
mfat_fstat() |
fstat() |
mfat_lseek() |
lseek() |
mfat_open() |
open() |
mfat_opendir() |
opendir() |
mfat_read() |
read() |
mfat_readdir() |
readdir() |
mfat_stat() |
stat() |
mfat_sync() |
sync() |
mfat_write() |
write() |
Note that the library is not fully POSIX compliant. For instance:
- Names of functions, types, and macros differ (an mfat_/MFAT_ prefix is used).
- Some types are different (e.g. date/time types and sizes/names of integral types).
- Some semantics are slightly different.
- Some functionality is missing.
- errno is not supported.
While the library itself is not fully POSIX compliant, it is suitable as a low level I/O implementation layer for higher level libraries, such as newlib.
It is also easy to modify existing programs that use POSIX I/O routines to use the MFAT library instead.