60-extlinux

#!/bin/sh

header() {
	echo "TIMEOUT ${TIMEOUT}" > ${OUTFILE}
	echo "DEFAULT entry0" >> ${OUTFILE}
	echo "MENU TITLE Boot menu" >> ${OUTFILE}
}

get_bootpath() {
	echo ${1} | sed "s#${BOOTPART}/#/#"
}

add_kernel() {
	ver=${1}
	kernel=$(get_bootpath "/boot/vmlinux-${ver}")
	initrd=$(get_bootpath "/boot/initramfs-${ver}.img")
	fdt=$(get_bootpath "/boot/dtbs/dtbs-${ver}/${DTBPATH}")
	cmdline="root=UUID=${UUID} ${CMDLINE}"

	echo "LABEL entry${ENTRY}" >> ${OUTFILE}
	echo "\tMENU LABEL Void GNU/Linux, with Linux ${ver}" >> ${OUTFILE}
	echo "\tLINUX ${kernel}" >> ${OUTFILE}
	if [ -e "${BOOTPART}/${initrd}" ]; then
		echo "\tINITRD ${initrd}" >> ${OUTFILE}
	fi
	if [ -n "${DTBPATH}" ] && [ -e "${BOOTPART}/${fdt}" ]; then
		echo "\tFDT ${fdt}" >> ${OUTFILE}
	fi
	if [ -n "${cmdline}" ]; then
		echo "\tAPPEND ${cmdline}" >> ${OUTFILE}
	fi
	ENTRY=$(expr ${ENTRY} + 1)
}

main() {
	if [ ! -d /boot/extlinux ]; then
		mkdir -p /boot/extlinux
	fi

	if [ -e ${CONF} ]; then
		. ${CONF}
	fi

	if [ -z "${CMDLINE}" ]; then
		CMDLINE=$(cat /proc/cmdline)
	fi

	header

	for kernel in $(ls /boot/vmlinu[xz]-* | sort -rV); do
		ver=$(echo ${kernel} | sed "s#/boot/vmlinu[xz]-\(.*\)#\\1#")
		echo "Adding kernel ${ver}"
		add_kernel ${ver}
	done
	mv ${OUTFILE} /boot/extlinux/extlinux.conf
}

CONF=/etc/default/extlinux
OUTFILE=$(mktemp)
BOOTPART=$(df -P /boot | tail -1 | awk '{ print $6 }')
ROOTDEV=$(df -P / | tail -1 | awk '{ print $1 }')
eval $(blkid -o export ${ROOTDEV})
ENTRY=0
main