#!/bin/sh

set -e

sudo="sudo"
if [ $(id -u) -eq 0 ]; then
    sudo=""
fi

usage() {
    echo "Usage: $0 <block-device>" >&2
    exit 1
}

if [ $# -ne 1 ]; then
    usage
fi

dev="$1"

if [ ! -b "$dev" ]; then
    usage
fi

set -x

$sudo parted -s "$dev" mklabel msdos

#sync?

nap_time=0
while :; do
    if $sudo sfdisk -L "$dev" >/dev/null 2>&1; then
        break
    fi
    if [ $nap_time -ge 30 ]; then
        echo "Giving up after $nap_time seconds failing to list partitions" >&2
        exit 1
    fi
    sleep 1
    nap_time=$(($nap_time + 1))
done

echo "Could list partitions after $nap_time seconds!" >&2