diskimage-builder/diskimage_builder/elements/dib-init-system/dib-init-system

#!/bin/bash

if [ ${DIB_DEBUG_TRACE:-0} -gt 0 ]; then
    set -x
fi
set -eu
set -o pipefail

# Debian Jessie and Debian Stretch use /bin/systemctl.
# (/sbin/init is only available if systemd-sysv is installed.)

if [ -f /usr/bin/systemctl -o -f /bin/systemctl ]; then
    echo "systemd"
elif [[ -f /sbin/initctl ]]; then
    echo "upstart"
elif [[ -f /etc/gentoo-release ]]; then
    if [[ "${GENTOO_PROFILE}" =~ systemd ]]; then
        echo "systemd"
    else
        echo "openrc"
    fi
elif [[ -f /sbin/init ]]; then
    if [[ -f /bin/systemd ]]; then
        echo "systemd"
    else
        echo "sysv"
    fi
else
    echo "Unknown init system"
    exit 1
fi