#/bin/sh

set -e

main() {
    local machine_id_file="/etc/machine-id"

    if [ -f "$machine_id_file" ]; then
        echo "Machine ID already generated. Doing nothing."
        exit 0
    fi

    # Accumulate data to create unique machine id
    local random_uuid=$(cat /proc/sys/kernel/random/uuid)

    # Ensure destination directory
    mkdir -p "$(dirname "$machine_id_file")"

    # Generate SHA256 hash of data and save it to $machine_id_file
    echo "$random_uuid" | sha256sum | cut -d ' ' -f1 > "$machine_id_file"
}

main