Crate macfs 

Read and write MFS (Macintosh File System) floppy disk images.

MFS is the flat filesystem the original 1984 Macintosh used on its 400K single-sided floppies. This crate reads and writes those volumes — as bare sector images or inside a DiskCopy 4.2 container, autodetected on open and written back in the same shape — with no dependencies beyond std.

Volumes are handled whole: MfsVolume::open pulls the entire image into memory, every operation works on that copy, and one MfsVolume::save_to call re-serializes it. Nothing touches the underlying stream in between, so a failed operation can never leave a half-written volume behind.

Files have the two classic Mac forks — Fork::Data and Fork::Resource — and names are stored as MacRoman, so lookups are case-insensitive and names round-trip through String.

Anything this crate does not interpret is preserved verbatim: boot blocks, reserved MDB and directory fields, and DiskCopy 4.2 tags. Opening an image and saving it again without changing anything reproduces the original bytes exactly.

Example

use macfs::{Fork, ImageFormat, MfsVolume};
use std::io::Cursor;

// Format a blank 400K volume in memory and put a file on it.
let mut vol = MfsVolume::format(MfsVolume::FLOPPY_400K, "My Disk", ImageFormat::Raw)?;
vol.create_file("Read Me", *b"TEXT", *b"MACA")?;
vol.write_fork("Read Me", Fork::Data, b"hello from 1984")?;
vol.write_fork("Read Me", Fork::Resource, &[0xAB; 300])?;

let mut image = Cursor::new(Vec::new());
vol.save_to(&mut image)?;

// Read it back. Name lookup is case-insensitive, as on a real Mac.
let disk = MfsVolume::open(Cursor::new(image.into_inner()))?;
assert_eq!(disk.info().name, "My Disk");
assert_eq!(disk.files().count(), 1);
assert_eq!(disk.read_fork("read me", Fork::Data)?, b"hello from 1984");
assert_eq!(disk.read_fork("READ ME", Fork::Resource)?, vec![0xAB; 300]);
assert!(disk.check().is_empty());

Structs

FileEntry

A read-only view of one file in the directory.

MacTimestamp

A classic Mac OS timestamp: seconds since 1904-01-01 00:00:00.

MfsVolume

An MFS volume, held in memory.

VolumeInfo

Volume-level metadata, as reported by MfsVolume::info.

Enums

Fork

Which of a file’s two forks to operate on.

ImageFormat

The container an image is stored in.

MfsError

Errors produced by this crate.

Type Aliases

Result