#!/bin/sh

. /etc/init.d/modlibrc

usage()
{
	cat << EOF
Usage: rc.mini_fo [on|off|status|store [ram|jffs2]|nostore]
mini_fo root mount script - can only be called as an 'init' replacement.
Parameters:
  status     - check status of mini_fo root; returns 'running' if mini_fo mount
               on '/' is active, 'stopped' otherwise.
  bootstatus - check boot status of mini_fo, returns 'enabled' if mini_fo is
               configured as init process
  on         - activate replacing 'init' by 'rc.mini_fo' -> boot with mini_fo
               root. Adds something like 'init=/etc/init.d/rc.mini_fo' to
               bootloader environment variable 'kernel_args'.
  store      - store changed data storage location in bootloader environment for
               later use with 'mount'. Adds variable 'mini_fo' to bootloader
               environment, setting its value. If called without parameter, this
               option prints the current 'mini_fo' values.
  nostore    - remove mini_fo variable from bootloader environment. Even though
               it does no harm to have the variable around in the environment
               all the time, you may optionally remove it again using this
               option.
  off        - deactivate replacing 'init' by 'rc.mini_fo' -> boot without
               mini_fo root. Removes 'init' from bootloader environment variable
               'kernel_args'.
Examples:
  - rc.mini_fo on
  - rc.mini_fo store jffs2
  - rc.mini_fo store
  - rc.mini_fo status
  - rc.mini_fo bootstatus
  - rc.mini_fo off
  - rc.mini_fo nostore
EOF
}

MINI_FO_ENV_VAR=kernel_args1
STORAGE=/sto
MOUNT_POINT=/opt

jffs2_mount() {
	xx=$(cat /proc/mtd | grep \"jffs2\")
	jffs2_pat=""
	jffs2_size=0
	jffs2_found=0
	echo "[jffs2] xx=$xx"
	for i in $xx; do
		echo "[jffs2] i=$i"
		case $i in
			*:)
				jffs2_pat=${i##mtd}
				jffs2_pat=${jffs2_pat%%:}
				echo "[jffs2] jffs2_pat=$jffs2_pat"
				;;
			00*)
				if [ $jffs2_found -eq 0 ]; then
					jffs2_size=$((0x$i / (2**16)))
					echo "[jffs2] jffs2_size=$jffs2_size"
				fi
				jffs2_found=1
				;;
		esac
	done
	if [ $jffs2_size -gt 0 ]; then
		echo "[jffs2] load jffs2 module"
		if grep -q "jffs2" /proc/filesystems || modprobe jffs2; then
			echo "[jffs2] mount jffs "
			mount -t jffs2 /dev/mtdblock${jffs2_pat} /sto
			jffs2_ok=$?
			if [ $jffs2_ok -ne 0 ]; then
				/bin/reinit_jffs2 -c /dev/mtdblock${jffs2_pat} -a -o /var/jffs2.image
				cp /var/jffs2.image /dev/mtdblock${jffs2_pat}
				echo "copying image ..."
				rm /var/jffs2.image
				echo "done."
				mount -t jffs2 /dev/mtdblock${jffs2_pat} $STORAGE
				jffs2_ok=$?
			fi
			if [ $jffs2_ok -eq 0 ]; then
				echo "[jffs2] write env variable jffs2_size to $jffs2_size"
				echo "jffs2_size $jffs2_size" >/proc/sys/urlader/environment
			fi
		fi
	fi
	if ! grep -q " $STORAGE jffs2 " /proc/mounts; then
		return 1
	fi
}

start() {
	[ -e /proc/mounts ] || mount proc
	if grep -q " / mini_fo " /proc/mounts; then
		echo "*** mini_fo already started, done. ***"
		return
	fi

	# Remove leading and trailing spaces from mini_fo. Trailing invisible
	# garbage can be part of the value if the user defines the variable via
	# Putty directly at the Eva console prompt via copy & paste.
	mini_fo=$(sed -rn "s/^$MINI_FO_ENV_VAR[[:space:]]+([^[:space:]]+).*/\1/p" /proc/sys/urlader/environment)
	mini_fo=${mini_fo##mini_fo\=}
	mini_fo=${mini_fo%% *}

	if [ -z "$mini_fo" ]; then
		echo "*** No mini_fo configured, done. ***"
		umount proc
		return
	fi
	if [ "$mini_fo" != "jffs2" -a "$mini_fo" != "ram" ]; then
		echo "*** Invalid mini_fo type '$mini_fo', must be 'ram' or 'jffs2', exiting. ***"
		umount proc
		return
	fi

	modprobe mini_fo
	if [ "$mini_fo" == "jffs2" ]; then
		echo "*** Mounting jffs2 to $STORAGE ... ***"
		if ! jffs2_mount; then
			echo "*** Mounting jffs2 failed. Mounting tmpfs instead ... ***"
			mount -t tmpfs none $STORAGE
		fi
	else
		mount -t tmpfs none $STORAGE
	fi
	mkdir -p $STORAGE/mini_fo
	if ! mount -t mini_fo -o base=/,sto=$STORAGE/mini_fo / $MOUNT_POINT; then
		echo "*** mini_fo mount failed, exiting. ***" >&2
		rmmod mini_fo
		return
	fi

	echo "*** Pivoting to mini_fo root ... ***"
	umount proc
	cd $MOUNT_POINT
	if pivot_root . oldroot; then
		# clean up
		mount -o move /oldroot/sto $STORAGE
		echo "*** mini_fo root pivoting succeeded, done. ***"
	else
		echo "*** mini_fo root pivoting failed, exiting. ***" >&2
	fi
}

bootstatus()
{
	grep "kernel_args" /proc/sys/urlader/environment | grep -q "init\=/etc/init\.d/rc\.mini_fo" \
			&& echo 'enabled' \
			|| echo 'disabled'
}

if [ "$PPID" == "0" ]; then
	echo "*** $0 called as an init process, start setting up mini_fo root ... ***"
	start
	echo "*** Switching to init ... ***"
	exec init >/dev/console 2>&1 <&1
fi

case $1 in
	start|stop)
		;;
	""|load)
		echo "mini_fo is $(bootstatus)"
		modreg cgi 'mini_fo' 'Mini_fo'
		modreg daemon --disable mini_fo
		;;
	unload)
		modunreg daemon 'mini_fo'
		modunreg cgi 'mini_fo'
		;;
	status)
		grep -q " / mini_fo " /proc/mounts \
			&& echo 'running' \
			|| echo 'stopped'
		;;
	bootstatus)
		bootstatus
		;;
	on)
		. kernel_args
		newval=$(ka_getArgs | sed -r 's/(.*[^ ])?( *init=[^ ]*)(.*)/\1\3/ ; s/^ +(.*)/\1/')
		echo "kernel_args init=/etc/init.d/rc.mini_fo $newval" > /proc/sys/urlader/environment
		echo "mini_fo root switched on (reboot to apply)"
		;;
	off)
		. kernel_args
		newval=$(ka_getArgs | sed -r 's/(.*[^ ])?( *init=[^ ]*)(.*)/\1\3/ ; s/^ +(.*)/\1/')
		echo "kernel_args $newval" > /proc/sys/urlader/environment
		echo "mini_fo root switched off (reboot to apply)"
		;;
	store)
		if [ "$2" ]; then
			if [ "$2" != "jffs2" -a "$2" != "ram" ]; then
				echo "Invalid mini_fo type '$2', must be 'ram' or 'jffs2'" >&2
				exit 1
			fi
			echo "$MINI_FO_ENV_VAR mini_fo=$2" > /proc/sys/urlader/environment
			echo "mini_fo variable added to bootloader environment"
		else
			mini_fo=$(sed -nr "s/^$MINI_FO_ENV_VAR[[:space:]]+(.*)/\1/p" /proc/sys/urlader/environment)
			[ -n "$mini_fo" ] \
				&& echo "$mini_fo" \
				|| echo "mini_fo variable is currently empty"
		fi
		;;
	nostore)
		echo "$MINI_FO_ENV_VAR" > /proc/sys/urlader/environment
		echo "mini_fo variable removed from bootloader environment"
		;;
	*)
		usage >&2
		exit 1
		;;
esac