#!/bin/ash
# Copyright (c) 2013 - OpenSLX GmbH
#
# This program is free software distributed under the GPL version 2.
# See http://openslx.org/COPYING
#
# If you have any feedback please consult http://openslx.org/feedback and
# send your feedback to feedback@openslx.org
#
# General information about OpenSLX can be found under http://openslx.org
#
# Local hard disk autodetection script for OpenSLX linux stateless clients,
# detecting swap and special partitions

#############################################################################

# Mount point for persistent scratch partition (type 45)
MOUNT_POINT_45="/opt/openslx/persistent"
PARTITION_FILE="/run/openslx/partitions"
readonly MOUNT_POINT_45 PARTITION_FILE
mkdir -p "/run/openslx"

# General formatter for the /tmp partition on a local harddisk
format_disk () {
	MOUNT_OPTIONS_SET_BY_FORMAT_DISK="" # Global var!
	local target="$1"
	local fslist="xfs jfs ext3 ext2 ext4"
	local fs
	local path
	[ $# -ge 2 ] && fslist="$2"
	for fs in $fslist ; do
		if grep -q "\\b${fs}\\b" "/proc/filesystems"; then
			# Filesystem already supported by running kernel
			:
		elif modprobe "${fs}"; then
			# Filesystem module could be loaded and should be supported now
			:
		else
			# Not supported, try next one
			continue
		fi
		if which "mkfs.$fs" ; then
			case "$fs" in
			xfs)
				fopt="-f -b size=4k -s size=4k -l size=512b" # fastest formatting possible :)
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK="-o noexec"
				;;
			ext2)
				fopt="-Fq"
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK="-o nocheck,noexec"
				;;
			ext3|ext4)
				fopt="-Fq"
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK="-o noexec"
				;;
			reiserfs)
				fopt="-f"
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK="-o noexec"
				;;
			jfs)
				fopt="-q"
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK="-o noexec"
				;;
			*)
				fopt=
				MOUNT_OPTIONS_SET_BY_FORMAT_DISK=
				;;
			esac
			mkfs.$fs ${fopt} "${target}" && return 0 # Success!
		fi
	done
	return 1
}

mount_temp () {
	local PRE=$(pwd)
	if ! cd /tmp; then
		mount_temp_fallback $@
		return $?
	fi
	mount $@ /tmp || return 1
	chmod a+rwxt /tmp
	# Move stuff from working directory, which is old /tmp, to new /tmp just mounted
	mv ./* ./.[!.]* ./..?* /tmp/ 2> /dev/null
	local OLD=$(LANG=C ls -alh | grep -v -E ' \.\.?$' | grep -v '^total')
	[ -n "$OLD" ] && echo -- "Leftovers:" && echo -- "$OLD"
	cd "$PRE"
}

mount_temp_fallback () {
	mkdir -p /tmptmp
	mv /tmp/* /tmp/.* /tmptmp/ 2> /dev/null
	mount $@ /tmp || return 1
	chmod a+rwxt /tmp
	mv /tmptmp/* /tmptmp/.* /tmp/
	rmdir /tmptmp
	return 0
}

fdisk -l | grep '^/dev/' > "$PARTITION_FILE"

if [ ! -s "$PARTITION_FILE" ]; then
	udevadm trigger
	sleep 3
	udevadm settle
	fdisk -l | grep '^/dev/' > "$PARTITION_FILE"
fi

echo "Partitions:"
cat "$PARTITION_FILE"

# Get all partitions with given id (list of /dev/sdXX)
get_all_with_id () {
	[ -z "$1" ] && return
	local ID=$1
	awk '{if (($2 == "*" && $6 == "'$ID'") || ($2 != "*" && $5 == "'$ID'")) print $1}' "$PARTITION_FILE" # watch out for non-spaced '$ID'
}

# Check for standard swap partitions and make them available to the system
HAVE_SWAP=no
for PART_DEV in $(get_all_with_id 82); do
	echo -e "$PART_DEV\tswap\t\tswap\t\tdefaults\t 0 0" >> "/etc/fstab"
	swapon "$PART_DEV" -p 10 && HAVE_SWAP=yes # low priority, in case we have zram swap, prefer that)
done

# We use special non assigned partition type (id44) for harddisk scratch
# space, thus no normal filesystem will be incidentally deleted or
# corrupted
HAVE_TEMP=no
for PART_DEV in $(get_all_with_id 44); do
	# check for supported filesystem and formatter
	if format_disk "$PART_DEV"; then
		# echo "$PART_DEV is mounted to /mnt/tmp at $(sysup)" >/tmp/tmpready
		mount_temp "$MOUNT_OPTIONS_SET_BY_FORMAT_DISK" "$PART_DEV" || continue
		echo -e "${PART_DEV}\t/tmp\t\tauto\t\tnoexec\t 0 0" >> "/etc/fstab"
		HAVE_TEMP=yes
		break
	else
		echo "formatting failed for some reason"
	fi # Made this non-forking, systemd should handle it - 2013-05-28
done

# Put detected linux partitions (83) into /etc/fstab with "noauto"
HAVE_PARTITION_45=no
for PART_DEV in $(get_all_with_id 83); do
	mkdir -p "/media/${PART_DEV#/dev/*}"
	echo -e "${PART_DEV}\t/media/${PART_DEV#/dev/*}\tauto\t\tnoauto,noexec\t 0 0" >> "/etc/fstab"
done

# special partition 45 (persistent scratch) to $MOUNT_POINT_45
for PART_DEV in $(get_all_with_id 45); do
	mkdir -p "$MOUNT_POINT_45"
	if ! mount -t auto -o noexec "${PART_DEV}" "$MOUNT_POINT_45"; then
		format_disk "$PART_DEV" "ext4 xfs jfs ext3" || continue
		mount -t auto -o noexec "${PART_DEV}" "$MOUNT_POINT_45" || continue
	fi
	echo -e "${PART_DEV}\t${MOUNT_POINT_45}\tauto\t\tnoauto,noexec\t\t 0 0" >> "/etc/fstab"
	HAVE_PARTITION_45=yes
	break
done

# and 46 to /media/devXX
for PART_DEV in $(get_all_with_id 46); do
	mkdir -p "/media/${PART_DEV#/dev/*}"
	#mount -t auto ${PART_DEV} /mnt/media/${PART_DEV#/dev/*} \n\
	#test -d /mnt/media/${PART_DEV#/dev/*}/home && \
	#  ln -sf /media/${PART_DEV#/dev/*} /var/home
	echo -e "${PART_DEV}\t/media/${PART_DEV#/dev/*}\tauto\t\tnoauto\t\t 0 0" >> "/etc/fstab"
done
if [ "$HAVE_PARTITION_45" = "no" ] && [ -d "$MOUNT_POINT_45" ]; then
	rm -f -- "$MOUNT_POINT_45"
fi

mount -a

# Make tmpfs if nothing could be mounted for /tmp
# 2016-10-12: Use a sane size of 66% which should be generous enough and prevent the machine from
# just crashing if RAM is too full. We previously hugely oversized since vmware wants at least as
# much free space as the VMs RAM; however, this requirement can be disabled with a vmx setting,
# which we're now doing.
if [ "$HAVE_TEMP" = "no" ]; then
	mount_temp -t tmpfs -o size=66% none
	slxlog "partition-temp" "Running /tmp on tmpfs only!" "$PARTITION_FILE"
fi
if [ "$HAVE_SWAP" = "no" ]; then
	TOTAL_RAM=$(grep ^MemTotal /proc/meminfo | awk '{print $2}')
	if [ -n "$TOTAL_RAM" ] && [ "$TOTAL_RAM" -lt "3000000" ]; then
		slxlog "partition-swap" "Have no (formatted) swap partition, using zram swap only!" "$PARTITION_FILE"
	fi
fi

exit 0