⚠️ This repository has moved to: https://gitlab.com/mbitsnbites/mfat

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.

Features

• 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).

Limitations

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.

POSIX compatibility

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:

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.

FAT Documentation

FAT.md