`hdd`: instruments for querying ATA and SCSI disks

Why?

Mainly because I was disappointed in all the available options for putting SMART and SCSI log info into various monitoring systems.

Scripts that parse smartctl output are just ugly, error prone hacks that still make me cringe.
To add support for different, programming-friendly output formats into smartctl (e.g. JSON), one basically needs to rewrite a lot of ad-hoc printfs scattered all over the source files, and it's not much easier if you decide to drop the idea of implementing some command-line switch in favour of simply changing the output format altogether. (Things are only getting more complex with smartd.)
libatasmart (and tools that it powers) can only work with ATA devices, and only on Linux, and expecting more from that library is simply naïve.

Build sample tool:

git clone https://github.com/vthriller/hdd-rs.git
cd hdd-rs/cli
cargo build --release
sudo ../target/release/hdd /dev/sda attrs --json

Put this into your Cargo.toml to start using this crate:

[dependencies]
hdd = "0.9"

This crate can be build on Rust >= 1.19.

Platforms and transports:

SCSI/ATA translation is also supported.

¹ Note that in Linux, ATA is only supported through SAT, although SG_IO kindly emulates that for SATA (and, possibly, PATA?) disks for us.

Features:

Documentation.
Tests.
More tests.
Even more tests: big-endian systems, old hardware…
rg 'TODO|FIXME|XXX|((?i)WTF)|unimplemented!|unwrap|expect' src {cli,sample-scsi}/src build.rs
Feature parity with [insert your favourite package name here].
Support for RAID weirdos (LSI, Adaptec, Areca, you name it) and USB bridges.
Debugging options (think smartctl -r ataioctl,2 or skdump) for CLI tool.
More devices (smartmontools can query NVMe devices).
More platforms (Windows, macOS, *BSD, Redox…).

This crate is distributed under the terms of Mozilla Public License version 2.0.