#!/bin/sh
# vim:set filetype=sh:

# NOTE: The mdev-conf APK handles this now, but only for xvd or sd links (not
#	both)

: "${LIBDIR:=$PREFIX/lib}"
. "$LIBDIR/tiny-cloud/common"

# nvme tool not installed?
[ -x /usr/sbin/nvme ] || log crit "nvme cli not installed"

raw_ebs_alias() {
	/usr/sbin/nvme id-ctrl "/dev/$BASE" -b 2>/dev/null |
	dd bs=32 skip=96 count=1 2>/dev/null
}

case $ACTION in
	add|"")
	BASE=$(echo "$MDEV" | sed -re 's/^(nvme[0-9]+n[0-9]+).*/\1/')
	PART=$(echo "$MDEV" | sed -re 's/nvme[0-9]+n[0-9]+p?//g')
	# TODO: deadline instead of max tries
	MAXTRY=30
	TRY=0
	until [ -n "$EBS" ]; do
		EBS=$(raw_ebs_alias | sed -nre '/^(\/dev\/)?(s|xv)d[a-z]{1,2} /p' | tr -d ' ')
		[ -n "$EBS" ] && break
		TRY=$((TRY + 1))
		if [ $TRY -eq $MAXTRY ]; then
		log err "Failed to get EBS volume alias for $MDEV after $MAXTRY attempts ($(raw_ebs_alias))"
		exit 1
		fi
		sleep 0.1
	done
	# remove any leading '/dev/', 'sd', or 'xvd', and append partition
	EBS=${EBS#/dev/}
	EBS=${EBS#sd}
	EBS=${EBS#xvd}$PART
	ln -sf "$MDEV" "sd$EBS" && log notice "Added sd$EBS symlink for $MDEV"
	ln -sf "$MDEV" "xvd$EBS" && log notice "Added xvd$EBS symlink for $MDEV"
	;;
	remove)
	for TARGET in sd* xvd*
	do
		[ "$(readlink "$TARGET" 2>/dev/null)" = "$MDEV" ] && rm -f "$TARGET" && \
		log notice "Removed $TARGET symlink for $MDEV"
	done
	;;
esac