Port f3probe, f3brew, and f3fix to macOS - #283
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The probing algorithm (libprobe.c) is platform-independent; only the device-access layer in libdevs.c was Linux-specific. This commit adds an __APPLE__ backend: - open() with F_NOCACHE replaces O_DIRECT (with _DARWIN_C_SOURCE so the Darwin extensions stay visible despite _POSIX_C_SOURCE) - DKIOCGETBLOCKCOUNT/DKIOCGETBLOCKSIZE replace BLKGETSIZE64/BLKSSZGET - whole-disk detection by device-name convention (/dev/rdiskN vs /dev/rdiskNsM) replaces the udev devtype check - manual USB reset (used by f3brew only; f3probe uses RT_NONE) is implemented by polling the device node instead of a udev monitor - software USB reset (USBDEVFS_RESET) reports EOPNOTSUPP on macOS - posix_fadvise(DONTNEED) is skipped; F_NOCACHE already bypasses the page cache f3fix on macOS is a new libparted-free backend (f3fix_darwin.c) that writes the MBR directly: fixing a fake drive only ever needs a single MBR partition ending at the last good sector reported by f3probe. MBR only for now; GPT is unnecessary for this use case. The Linux build is unchanged: all __APPLE__ additions are guarded and the Linux path compiles the same objects with no new warnings. Tested on macOS 26.5 (Intel, MacBookPro16,1): make extra builds all three tools with clang and brew argp-standalone, and f3probe --debug-unit-test reports Perfect. Closes AltraMayor#8. Closes AltraMayor#135.
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For anyone who wants to try this on macOS without building manually, I have published a Homebrew tap pinned to this PR branch: Tap: https://github.com/sbrunner-atx/homebrew-f3 (README includes macOS usage notes: raw whole-disk device, unmount first, sudo). I will retire the tap once this is merged and the official formula picks up Full f3probe hardware-validation transcript (genuine SanDisk Ultra 128 GB, macOS 26.5 Intel) available on request. |
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What
Ports the three extra tools - f3probe, f3brew, and f3fix - to macOS, as invited by #8 and requested in #135.
How
The probing algorithm (libprobe.c) is already platform-independent; only the device-access layer needed work. All changes are behind APPLE guards:
f3fix on macOS is a new libparted-free backend (f3fix_darwin.c) that writes the MBR directly - fixing a fake drive only ever needs a single MBR partition ending at the last good sector from f3probe. MBR only for now; GPT support could follow if there is demand.
Validation
On macOS 26.5 (Intel, MacBookPro16,1), clang + brew argp-standalone:
The Linux build is unchanged: gcc on Ubuntu compiles all targets with no new warnings, and the Linux code path is untouched.
Notes