raw-image-builder

#! /bin/bash -e

# $1: partition number, $2: partition type, $3: partition mount options
function mount_partition () {
	if [ "$2" ]; then
		mkdir "$1"
		if [ "$3" ]; then
			mount -v -o "$3" "${loop_device}$1" "$1"
		else
			mount -v "${loop_device}$1" "$1"
		fi
	fi
}

function cleanup () {
	echo 'Performing cleanup ...'
	cd "$temp_dir" || exit 1
	for i in 'p1' 'p2' 'p3' 'p4'; do
		[ -d "$i" ] && umount "$i" || umount_fail=1
	done
	if ! ((umount_fail)); then
		rm -r "${temp_dir}"
	else
		echo "WARNING: umount failed" >&2
	fi

	losetup -d "$loop_device"
}

if [ ! "$SOLUTION" ]; then
	echo "Solution unspecified!" >&2
	echo "Please set the SOLUTION environment variable!" >&2
	exit 1
fi

if [ ! "$DEVICE_NAME" ]; then
	echo "Device name unspecified!" >&2
	echo "Please set the DEVICE_NAME environment variable!" >&2
	exit 1
fi

if [ ! -e solutions/"$SOLUTION" ]; then
	echo "Cannot find solution file!" >&2
	exit 1
fi

source solutions/"$SOLUTION"

mkdir -p out aux_log
set -o pipefail

image_name="${DEVICE_NAME}_${SOLUTION}_$(date -u +%F)${IMAGE_NAME_EXTRA}"

apt-get install ${DEPENDENCIES} -y > aux_log/"${image_name}".log

dd if=/dev/zero of=out/"${image_name}".img bs=1M count="${IMAGE_TOTAL_SIZE}"

if [ "$(type -t "GDISK_COMMANDS")" = "function" ]; then
	GDISK_COMMANDS "out/${image_name}.img"
else
	PLAN="label:dos\nstart=2048"
	# 2 partitions or more
	if [ $(("$TRIPLE_PARTITION" + "$DUAL_PARTITION")) -ge 0 ]; then
		# append size constraint to the first partition
		PLAN+=",size=+${FIRST_PARTITION_SIZE}M"
	fi
	# 3 partitions
	if (("$TRIPLE_PARTITION")); then
		# append size constraint to the second partition
		PLAN+="\nsize=+${SECOND_PARTITION_SIZE}M"
	fi
	# This `type=83` is actually a workaround for sfdisk to create a partition that is
	# extended to the end of the disk since we don't know the start or size of the partition
	PLAN+="\ntype=83\nwrite\n"
	echo -e "$PLAN" | sfdisk "out/${image_name}.img"
	if [ "$(type -t "EXTRA_FDISK_COMMANDS")" = "function" ]; then
		EXTRA_FDISK_COMMANDS "out/${image_name}.img"
	fi
fi

loop_device=$(losetup -Pfv --show out/"${image_name}".img)
sync
partprobe "${loop_device}"

if [ "$FIRST_PARTITION_TYPE" ]; then
	"mkfs.${FIRST_PARTITION_TYPE}" "${loop_device}"p1
fi
if [ "$SECOND_PARTITION_TYPE" ]; then
	"mkfs.${SECOND_PARTITION_TYPE}" "${loop_device}"p2
fi
if [ "$THIRD_PARTITION_TYPE" ]; then
	"mkfs.${THIRD_PARTITION_TYPE}" "${loop_device}"p3
fi
if [ "$FOURTH_PARTITION_TYPE" ]; then
	"mkfs.${FOURTH_PARTITION_TYPE}" "${loop_device}"p4
fi


# This environment variables are passed to do_fill_image
export IMAGE="$(readlink -e out/${image_name}.img)"
export IMAGE_DEVICE="${loop_device}"

temp_dir=$(mktemp -d)
umount_fail=0
pushd "$temp_dir"
	trap 'echo "WARNING: Interrupt signal received!"; cleanup' SIGHUP SIGINT SIGQUIT SIGTERM
	trap 'cleanup' EXIT
	mount_partition "p1" "$FIRST_PARTITION_TYPE"  "$FIRST_PARTITION_MOUNT_OPTIONS"
	mount_partition "p2" "$SECOND_PARTITION_TYPE" "$SECOND_PARTITION_MOUNT_OPTIONS"
	mount_partition "p3" "$THIRD_PARTITION_TYPE"  "$THIRD_PARTITION_MOUNT_OPTIONS"
	mount_partition "p4" "$FOURTH_PARTITION_TYPE" "$FOURTH_PARTITION_MOUNT_OPTIONS"
	do_fill_image
	sync && sleep 10
popd