#!/bin/bash
# This file is part of Ian Kelling's automated-distro-installer
# Copyright (C) 2024 Ian Kelling

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

# input eg: /dev/sda1 or /dev/sda
# output: /dev/disk/by-id/model+serial, or if no link exists, the same as input

short_dev=$1
if [[ ! -e $short_dev ]]; then
  echo "devbyid: error: argument=$short_dev does not exist"
  exit 1
fi

# devices are identified by model+serial num
# and for ssd/hdd: wwn, and for nvme: eui.
# model+serial gives me more info, so use that.
shopt -s extglob
for id in /dev/disk/by-id/!(nvme-eui*|wwn*); do
  [[ -e $id ]] || break # if we matched nothing
  if [[ $(readlink -f $id) == "$short_dev" ]]; then
    printf '%s\n' "$id"
    exit
  fi
done
# a vm may not have a by-id link.
printf '%s\n' "$short_dev"