luci-app-advanced-reboot: rewrite rpcd in shell script + bugfixes

Signed-off-by: Stan Grishin <stangri@melmac.net>

1 files changed, 370 insertions, 342 deletions

diff --git a/applications/luci-app-advanced-reboot/root/usr/libexec/rpcd/luci.advanced_reboot b/applications/luci-app-advanced-reboot/root/usr/libexec/rpcd/luci.advanced_reboot
index a6c7c0e540..c78a61d611 100755
--- a/applications/luci-app-advanced-reboot/root/usr/libexec/rpcd/luci.advanced_reboot
+++ b/applications/luci-app-advanced-reboot/root/usr/libexec/rpcd/luci.advanced_reboot
@@ -1,362 +1,390 @@
-#!/usr/bin/env lua
+#!/bin/sh
+# Copyright 2017-2020 Stan Grishin (stangri@melmac.net)
+# shellcheck disable=SC2039,SC1091
 
-local json = require "luci.jsonc"
-local nixio = require "nixio"
-local fs   = require "nixio.fs"
-local sys  = require "luci.sys"
-local util = require "luci.util"
+readonly devices_dir="/usr/share/advanced-reboot/devices/"
 
-local devices_dir = "/usr/share/advanced-reboot/devices/"
+. /lib/functions.sh
+. /usr/share/libubox/jshn.sh
 
-local function logger(t)
-	util.exec("logger -t advanced-reboot '" .. tostring(t) .. "'")
-end
+logger() { /usr/bin/logger -t advanced-reboot "$1"; }
 
-local function is_alt_mountable(p1_mtd, p2_mtd)
-	if p1_mtd:sub(1,3) == "mtd" and
-				 p2_mtd:sub(1,3) == "mtd" and
-				 fs.access("/usr/sbin/ubiattach") and
-				 fs.access("/usr/sbin/ubiblock") and
-				 fs.access("/bin/mount") then
-		return true
+is_alt_mountable() {
+	local p1_mtd="$1" p2_mtd="$2"
+	if [ "${p1_mtd:0:3}" = "mtd" ] && [ "${p2_mtd:0:3}" = "mtd" ] && \
+		[ -x "/usr/sbin/ubiattach" ] && \
+		[ -x "/usr/sbin/ubiblock" ] && \
+		[ -x "/bin/mount" ]; then
+		return 0
 	else
-		return false
-	end
-end
-
-local function alt_partition_mount(op_ubi)
-	local ubi_dev
-	util.exec('for i in alt_rom alt_overlay firmware; do [ ! -d "$i" ] && mkdir -p "/alt/${i}"; done')
-	ubi_dev = tostring(util.exec("ubiattach -m " .. tostring(op_ubi)))
-	_, _, ubi_dev = ubi_dev:find("UBI device number (%d+)")
-	if not ubi_dev then
-		util.exec("ubidetach -m " .. tostring(op_ubi))
-		return
-	end
-	util.exec("ubiblock --create /dev/ubi" .. ubi_dev .. "_0")
-	util.exec("mount -t squashfs -o ro /dev/ubiblock" .. ubi_dev .. "_0 /alt/alt_rom")
-	util.exec("mount -t ubifs /dev/ubi" .. ubi_dev .. "_1 /alt/alt_overlay")
---	util.exec("mount -t overlay overlay -o noatime,lowerdir=/alt/rom,upperdir=/alt/overlay/upper,workdir=/alt/overlay/work /alt/firmware")
-end
-
-local function alt_partition_unmount(op_ubi)
-	local i
-	local mtdCount = tonumber(util.exec("ubinfo | grep 'Present UBI devices' | grep -c ','"))
-	mtdCount = mtdCount and mtdCount + 1 or 10
---	util.exec("[ -d /alt/firmware ] && umount /alt/firmware")
-	util.exec("[ -d /alt/alt_overlay ] && umount /alt/alt_overlay")
-	util.exec("[ -d /alt/alt_rom ] && umount /alt/alt_rom")
-	for i = 0, mtdCount do
-		if not fs.access("/sys/devices/virtual/ubi/ubi" .. tostring(i) .. "/mtd_num") then break end
-		ubi_mtd =  tonumber(util.trim(util.exec("cat /sys/devices/virtual/ubi/ubi" .. i .. "/mtd_num")))
-		if ubi_mtd and ubi_mtd == op_ubi then
-			util.exec("ubiblock --remove /dev/ubi" .. tostring(i) .. "_0")
-			util.exec("ubidetach -m " .. tostring(op_ubi))
-			util.exec('rm -rf /alt')
-		end
-	end
-end
-
-local function get_partition_os_info(op_ubi)
-	local cp_info, op_info
-	if fs.access("/etc/os-release") then
-		cp_info = util.trim(util.exec('. /etc/os-release && echo "$PRETTY_NAME"'))
-		if cp_info:find("SNAPSHOT") then
-			cp_info = util.trim(util.exec('. /etc/os-release && echo "$OPENWRT_RELEASE"'))
-		end
-	end
-	logger(string.format("attempting to mount alternative partition (mtd%s)", tostring(op_ubi)))
-	alt_partition_unmount(op_ubi)
-	alt_partition_mount(op_ubi)
-	if fs.access("/alt/alt_rom/etc/os-release") then
-		op_info = util.trim(util.exec('. /alt/alt_rom/etc/os-release && echo "$PRETTY_NAME"'))
-		if op_info:find("SNAPSHOT") then
-			op_info = util.trim(util.exec('. /alt/alt_rom/etc/os-release && echo "$OPENWRT_RELEASE"'))
-		end
-	end
-	logger(string.format("attempting to unmount alternative partition (mtd%s)", tostring(op_ubi)))
-	alt_partition_unmount(op_ubi)
-	return cp_info, op_info
-end
-
-local function find_device_data(romBoardName)
-	local filename
-
-	for filename in fs.dir(devices_dir) do
-		local filedata = fs.readfile(devices_dir .. filename)
-
-		local p = json.parse(filedata or {})
-
-		if p then
-			local boardName
-
-			if p.boardName then
-				boardName = p.boardName:gsub('%p','')
-				if romBoardName:match(boardName) then return p end
-			end
-			if p.boardNames then
-				for i, v in pairs(p.boardNames) do
-					boardName = v:gsub('%p','')
-					if romBoardName:match(boardName) then return p end
-				end
-			end
-		end
-	end
-
-	return nil
-end
-
-local methods = {
-	obtain_device_info = {
-		call = function()
-
-			local ret = {}
-			local romBoardName = fs.readfile('/tmp/sysinfo/board_name')
-
-			if not romBoardName then
-				ret.error = 'NO_BOARD_NAME'
-				return ret
-			end
-
-			romBoardName = romBoardName:gsub('\n','')
+		return 1
+	fi
+}
 
-			ret.rom_board_name = romBoardName
+alt_partition_mount() {
+	local ubi_dev op_ubi="$1"
+	for i in alt_rom alt_overlay firmware; do [ ! -d "$i" ] && mkdir -p "/alt/${i}"; done
+	ubi_dev="$(ubiattach -m "$op_ubi")"
+	ubi_dev="$(echo "$ubi_dev" | sed -n "s/^UBI device number\s*\(\d*\),.*$/\1/p")"
+	if [ -z "$ubi_dev" ]; then 
+		ubidetach -m "$op_ubi"
+		return 1
+	fi
+	ubiblock --create "/dev/ubi${ubi_dev}_0"
+	mount -t squashfs -o ro "/dev/ubiblock${ubi_dev}_0" /alt/alt_rom
+	mount -t ubifs "/dev/ubi${ubi_dev}_0" /alt/alt_overlay
+	# mount -t overlay overlay -o noatime,lowerdir=/alt/rom,upperdir=/alt/overlay/upper,workdir=/alt/overlay/work /alt/firmware
+}
 
-			romBoardName = romBoardName:gsub('%p','')
+alt_partition_unmount() {
+	local mtdCount i=0 op_ubi="$1"
+	mtdCount="$(ubinfo | grep 'Present UBI devices' | tr ',' '\n' | grep -c 'ubi')"
+	[ -z "$mtdCount" ] && mtdCount=10
+	# [ -d /alt/firmware ] && umount /alt/firmware
+	[ -d /alt/alt_overlay ] && umount /alt/alt_overlay
+	[ -d /alt/alt_rom ] && umount /alt/alt_rom
+	while [ "$i" -le "$mtdCount" ]; do
+		if [ ! -e "/sys/devices/virtual/ubi/ubi${i}/mtd_num" ]; then
+			break
+		fi
+		ubi_mtd="$(cat /sys/devices/virtual/ubi/ubi${i}/mtd_num)"
+		if [ -n "$ubi_mtd" ] && [ "$ubi_mtd" = "$op_ubi" ]; then
+			ubiblock --remove /dev/ubi${i}_0
+			ubidetach -m "$op_ubi"
+			rm -rf /alt
+		fi
+		i=$((i + 1))
+	done
+}
 
-			local p, boardName, n, p1_label, p1_version, p2_label, p2_version, p1_os, p2_os
-			local current_partition
-			local op_ubi, cp_info, op_info, zyxelFlagPartition
+get_main_partition_os_info(){
+	local cp_info
+	if [ -s "/etc/os-release" ]; then
+		cp_info="$(. /etc/os-release && echo "$PRETTY_NAME")"
+		if [ "${cp_info//SNAPSHOT}" != "$cp_info" ]; then
+			cp_info="$(. /etc/os-release && echo "${OPENWRT_RELEASE%%-*}")"
+		fi
+	fi
+	echo "$cp_info"
+}
 
-			p = find_device_data(romBoardName)
+get_alt_partition_os_info(){
+	local op_info op_ubi="$1"
+	logger "attempting to mount alternative partition (mtd${op_ubi})"
+	alt_partition_unmount "$op_ubi"
+	alt_partition_mount "$op_ubi"
+	if [ -s "/alt/alt_rom/etc/os-release" ]; then
+		op_info="$(. /alt/alt_rom/etc/os-release && echo "$PRETTY_NAME")"
+		if [ "${op_info//SNAPSHOT}" != "$op_info" ]; then
+			op_info="$(. /alt/alt_rom/etc/os-release && echo "${OPENWRT_RELEASE%%-*}")"
+		fi
+	fi
+	logger "attempting to unmount alternative partition (mtd${op_ubi})"
+	alt_partition_unmount "$op_ubi"
+	echo "$op_info"
+}
 
-			if p then
-				if p.labelOffset then
-					if p.partition1MTD then
-						p1_label = util.trim(util.exec("dd if=/dev/" .. p.partition1MTD .. " bs=1 skip=" .. p.labelOffset .. " count=128" .. " 2>/dev/null"))
-						n, p1_version = p1_label:match('(Linux)-([%d|.]+)')
-					end
+find_device_data(){
+	local boardNames filename i romBoardName="$1"
+	for filename in "${devices_dir}"*.json; do
+		[ "$filename" = "${devices_dir}*.json" ] && return
+		json_load_file "$filename"
+		json_get_values boardNames 'boardNames'
+		json_cleanup
+		for i in $boardNames; do 
+			if [ "$i" = "$romBoardName" ]; then
+				echo "$filename"
+				return
+			fi
+		done
+	done
+}
 
-					if p1_label then
-						if p1_label:find("LEDE") then p1_os = "LEDE" end
-						if p1_label:find("OpenWrt") then p1_os = "OpenWrt" end
-						if p.vendorName and p1_label:find(p.vendorName) then p1_os = p.vendorName end
-					end
+print_json() { json_init; json_add_string "$1" "$2"; json_dump; json_cleanup; }
 
-					if not p1_os then
-						p1_os = (p.vendorName and p.vendorName or 'Unknown') .. "/" .. "Unknown"
-					end
-					if p1_os and p1_version then p1_os = p1_os .. " (Linux " .. p1_version .. ")" end
+obtain_device_info(){
+	local romBoardName p zyxelFlagPartition
+	local vendorName deviceName partition1MTD partition2MTD labelOffset
+	local bootEnv1 bootEnv1Partition1Value bootEnv1Partition2Value
+	local bootEnv2 bootEnv2Partition1Value bootEnv2Partition2Value
+	local p1_label p1_version p2_label p2_version p1_os p2_os
+	local current_partition op_ubi cp_info op_info
 
-					if p.partition2MTD then
-						p2_label = util.trim(util.exec("dd if=/dev/" .. p.partition2MTD .. " bs=1 skip=" .. p.labelOffset .. " count=128" .. " 2>/dev/null"))
-						n, p2_version = p2_label:match('(Linux)-([%d|.]+)')
-					end
+	romBoardName="$(cat /tmp/sysinfo/board_name)"
+	if [ -z "$romBoardName" ]; then
+		print_json 'error' 'NO_BOARD_NAME'
+		return
+	fi
 
-					if p2_label then
-						if p2_label:find("LEDE") then p2_os = "LEDE" end
-						if p2_label:find("OpenWrt") then p2_os = "OpenWrt" end
-						if p.vendorName and p2_label:find(p.vendorName) then p2_os = p.vendorName end
-					end
+	p="$(find_device_data "$romBoardName")"
+	if [ -z "$p" ] || [ ! -s "$p" ]; then
+		print_json 'rom_board_name' "$romBoardName"
+		return
+	fi
+
+	json_load_file "$p"
+	for i in vendorName deviceName partition1MTD partition2MTD labelOffset \
+		bootEnv1 bootEnv1Partition1Value bootEnv1Partition2Value \
+		bootEnv2 bootEnv2Partition1Value bootEnv2Partition2Value; do
+		json_get_var $i "$i"
+	done
+	json_cleanup
+
+	if [ -n "$labelOffset" ]; then
+		if [ -n "$partition1MTD" ]; then
+			p1_label="$(dd if="/dev/${partition1MTD}" bs=1 skip="${labelOffset}" count=64 2>/dev/null)"
+			if [ -n "$p1_label" ]; then
+				p1_version="$(echo "$p1_label" | sed -n "s/\(.*\)Linux-\([0-9.]\+\).*$/\2/p")"
+				if [ "${p1_label//LEDE}" != "$p1_label" ]; then p1_os="LEDE"; fi
+				if [ "${p1_label//OpenWrt}" != "$p1_label" ]; then p1_os="OpenWrt"; fi
+				if [ -n "$vendorName" ] && [ "${p1_label//$vendorName}" != "$p1_label" ]; then 
+					p1_os="$vendorName"
+				fi
+			fi
+			if [ -z "$p1_os" ]; then
+				p1_os="${vendorName:-Unknown}/Unknown"
+			fi
+		fi
+
+		if [ -n "$partition2MTD" ]; then
+			p2_label="$(dd if="/dev/${partition2MTD}" bs=1 skip="${labelOffset}" count=64 2>/dev/null)"
+			if [ -n "$p2_label" ]; then
+				p2_version="$(echo "$p2_label" | sed -n "s/\(.*\)Linux-\([0-9.]\+\).*$/\2/p")"
+				if [ "${p2_label//LEDE}" != "$p2_label" ]; then p2_os="LEDE"; fi
+				if [ "${p2_label//OpenWrt}" != "$p2_label" ]; then p2_os="OpenWrt"; fi
+				if [ -n "$vendorName" ] && [ "${p2_label//$vendorName}" != "$p2_label" ]; then 
+					p2_os="$vendorName"
+				fi
+			fi
+			if [ -z "$p2_os" ]; then
+				p2_os="${vendorName:-Unknown}/Unknown"
+			fi
+		fi
+	else
+		p1_os="${vendorName}/Unknown (Compressed)"
+		p2_os="${vendorName}/Unknown (Compressed)"
+	fi
+
+	if [ -n "$bootEnv1" ]; then
+		if [ -x "/usr/sbin/fw_printenv" ] && [ -x "/usr/sbin/fw_setenv" ]; then
+			current_partition="$(/usr/sbin/fw_printenv -n "${bootEnv1}")"
+		fi
+	else
+		if [ -z "$zyxelFlagPartition" ]; then
+			zyxelFlagPartition="$(find_mtd_part 0:DUAL_FLAG 2>/dev/null)"
+		fi
+		if [ -n "$zyxelFlagPartition" ]; then
+			current_partition="$(dd if="${zyxelFlagPartition}" bs=1 count=1 2>/dev/null | hexdump -n 1 -e '1/1 "%d"')"
+		else
+			print_json 'error' 'NO_DUAL_FLAG'
+			logger "Unable to find Dual Boot Environment or Dual Boot Flag Partition."
+			return
+		fi
+	fi
+
+	if is_alt_mountable "$partition1MTD" "$partition2MTD"; then
+		if [ "$current_partition" = "$bootEnv1Partition1Value" ]; then
+			op_ubi=$(( ${partition2MTD:3:3} + 1 ))
+		else
+			op_ubi=$(( ${partition1MTD:3:3} + 1 ))
+		fi
+		cp_info="$(get_main_partition_os_info $op_ubi)"
+		op_info="$(get_alt_partition_os_info $op_ubi)"
+		if [ "$current_partition" = "$bootEnv1Partition1Value" ]; then
+			p1_os="${cp_info:-$p1_os}"
+			p2_os="${op_info:-$p2_os}"
+		else
+			p1_os="${op_info:-$p1_os}"
+			p2_os="${cp_info:-$p2_os}"
+		fi
+	fi
+	if [ -n "$p1_os" ] && [ -n "$p1_version" ]; then
+		p1_os="$p1_os (Linux ${p1_version})"
+	fi
+	if [ -n "$p2_os" ] && [ -n "$p2_version" ]; then
+		p2_os="$p2_os (Linux ${p2_version})"
+	fi
+
+
+	json_init
+	json_add_int 'current_partition' "$current_partition"
+	json_add_string 'device_name' "$vendorName $deviceName"
+	json_add_array 'partitions'
+	json_add_object
+	if [ "$bootEnv1Partition1Value" = "$current_partition" ]; then
+		json_add_string 'state' "Current"
+	else
+		json_add_string 'state' "Alternative"
+	fi
+	json_add_string 'os' "$p1_os"
+	json_add_int 'number' "$bootEnv1Partition1Value"
+	json_close_object
+	json_add_object
+	if [ "$bootEnv1Partition2Value" = "$current_partition" ]; then
+		json_add_string 'state' "Current"
+	else
+		json_add_string 'state' "Alternative"
+	fi
+	json_add_string 'os' "$p2_os"
+	json_add_int 'number' "$bootEnv1Partition2Value"
+	json_close_object
+	json_close_array
+	json_add_string 'rom_board_name' "$romBoardName"
+	json_dump; json_cleanup;
+}
 
-					if not p2_os then
-						p2_os = (p.vendorName and p.vendorName or 'Unknown') .. "/" .. "Unknown"
-					end
-					if p2_os and p2_version then p2_os = p2_os .. " (Linux " .. p2_version .. ")" end
-				else
-					p1_os = p.vendorName .. "/" .. "Unknown" .. " (" .. "Compressed" .. ")"
-					p2_os = p.vendorName .. "/" .. "Unknown" .. " (" .. "Compressed" .. ")"
-				end
+toggle_boot_partition(){
+	local zyxelFlagPartition zyxelBootFlag zyxelNewBootFlag curEnvSetting newEnvSetting
+	local romBoardName p
+	local bev1 bev2 bev1p1 bev1p2 bev2p1 bev2p2
+	local vendorName deviceName partition1MTD partition2MTD labelOffset
+	local bootEnv1 bootEnv1Partition1Value bootEnv1Partition2Value
+	local bootEnv2 bootEnv2Partition1Value bootEnv2Partition2Value
+
+	romBoardName="$(cat /tmp/sysinfo/board_name)"
+	if [ -z "$romBoardName" ]; then
+		print_json 'error' 'NO_BOARD_NAME'
+		return
+	fi
 
-				if p.bootEnv1 then
-					if fs.access("/usr/sbin/fw_printenv") and fs.access("/usr/sbin/fw_setenv") then
-						current_partition = tonumber(util.trim(util.exec("fw_printenv -n " .. p.bootEnv1)))
-					end
+	p="$(find_device_data "$romBoardName")"
+	if [ -z "$p" ] || [ ! -s "$p" ]; then
+		print_json 'rom_board_name' "$romBoardName"
+		return
+	fi
+
+	json_load_file "$p"
+	for i in vendorName deviceName partition1MTD partition2MTD labelOffset \
+		bootEnv1 bootEnv1Partition1Value bootEnv1Partition2Value \
+		bootEnv2 bootEnv2Partition1Value bootEnv2Partition2Value; do
+		json_get_var $i "$i"
+	done
+	json_cleanup
+
+	bev1="$bootEnv1"
+	bev2="$bootEnv2"
+
+	if [ -n "${bev1}${bev2}" ]; then # Linksys devices
+		if [ -n "$bev1" ]; then
+			curEnvSetting="$(fw_printenv -n "${bev1}")"
+			if [ -z "$curEnvSetting" ]; then
+				logger "$(printf "Unable to obtain firmware environment variable: %s." "$bev1")"
+				json_init
+				json_add_string 'error' 'NO_FIRM_ENV'
+				json_add_array 'args'
+				json_add_string "$bev1"
+				json_close_array
+				json_add_string 'rom_board_name' "$romBoardName"
+				json_dump; json_cleanup;
+				return
+			else
+				bev1p1="$bootEnv1Partition1Value"
+				bev1p2="$bootEnv1Partition2Value"
+				if [ "$curEnvSetting" = "$bev1p1" ]; then
+					newEnvSetting="$bev1p2"
 				else
-					if not zyxelFlagPartition then zyxelFlagPartition = util.trim(util.exec(". /lib/functions.sh; find_mtd_part 0:DUAL_FLAG")) end
-					if zyxelFlagPartition then
-						current_partition = tonumber(util.exec("dd if=" .. zyxelFlagPartition .. " bs=1 count=1 2>/dev/null | hexdump -n 1 -e '1/1 \"%d\"'"))
-					else
-						ret.error = 'NO_DUAL_FLAG'
-						logger("Unable to find Dual Boot Flag Partition.")
-						return ret
-					end
-				end
-
-				ret.current_partition = current_partition
-
-				if is_alt_mountable(p.partition1MTD, p.partition2MTD) then
-					if current_partition == p.bootEnv1Partition1Value then
-						op_ubi = tonumber(p.partition2MTD:sub(4)) + 1
-					else
-						op_ubi = tonumber(p.partition1MTD:sub(4)) + 1
-					end
-					local cp_info, op_info = get_partition_os_info(op_ubi)
-					if current_partition == p.bootEnv1Partition1Value then
-						p1_os = cp_info or p1_os
-						p2_os = op_info or p2_os
-					else
-						p1_os = op_info or p1_os
-						p2_os = cp_info or p2_os
-					end
-				end
-
-				ret.device_name = (p.vendorName and p.vendorName or "") .. " " .. p.deviceName
-
-				ret.partitions = {
-					{
-						os = p1_os,
-						state = p.bootEnv1Partition1Value == current_partition and 'Current' or 'Alternative',
-						number = p.bootEnv1Partition1Value
-					},
-					{
-						os = p2_os,
-						state = p.bootEnv1Partition2Value == current_partition and 'Current' or 'Alternative',
-						number = p.bootEnv1Partition2Value
-					}
-				}
-			end
-
-			return ret
-		end
-	},
-	toggle_boot_partition = {
-		call = function()
-			local ret = {}
-			local zyxelFlagPartition, zyxelBootFlag, zyxelNewBootFlag, errorCode, curEnvSetting, newEnvSetting
-
-			local romBoardName = fs.readfile('/tmp/sysinfo/board_name')
-
-			if not romBoardName then
-				ret.error = 'NO_BOARD_NAME'
-				return ret
-			end
-
-			romBoardName = romBoardName:gsub('\n',''):gsub('%p','')
-			p = find_device_data(romBoardName)
-			local bev1, bev2 = p.bootEnv1, p.bootEnv2
-
-			if bev1 or bev2 then -- Linksys devices
-				if bev1 then
-					curEnvSetting = tonumber(util.trim(util.exec("fw_printenv -n " .. bev1)))
-					if not curEnvSetting then
-						logger(string.format("Unable to obtain firmware environment variable: %s.", bev1))
-						ret.error = 'NO_FIRM_ENV'
-						ret.args = { bev1 }
-						return ret
-					else
-						local bev1p1, bev1p2 = p.bootEnv1Partition1Value, p.bootEnv1Partition2Value
-						newEnvSetting = curEnvSetting == bev1p1 and bev1p2 or bev1p1
-						errorCode = sys.call("fw_setenv " .. bev1 .. " " .. newEnvSetting)
-						if errorCode ~= 0 then
-							logger(string.format("Unable to set firmware environment variable: %s to %s.", bev1, newEnvSetting))
-							ret.error = 'ERR_SET_ENV'
-							ret.args = { bev1, newEnvSetting }
-							return ret
-						end
-					end
-				end
-				if bev2 then
-					curEnvSetting = util.trim(util.exec("fw_printenv -n " .. bev2))
-					if not curEnvSetting then
-						logger(string.format("Unable to obtain firmware environment variable: %s.", bev2))
-						ret.error = 'NO_FIRM_ENV'
-						ret.args = { bev2 }
-						return ret
-					else
-						local bev2p1, bev2p2 = p.bootEnv2Partition1Value, p.bootEnv2Partition1Value
-						newEnvSetting = curEnvSetting == bev2p1 and bev2p2 or bev2p1
-						errorCode = sys.call("fw_setenv " .. bev2 .. " '" .. newEnvSetting .. "'")
-						if errorCode ~= 0 then
-							logger(string.format("Unable to set firmware environment variable: %s to %s.", bev2, newEnvSetting))
-							ret.error = 'ERR_SET_ENV'
-							ret.args = { bev2, newEnvSetting }
-							return ret
-						end
-					end
-				end
-			else -- NetGear device
-				if not zyxelFlagPartition then zyxelFlagPartition = util.trim(util.exec(". /lib/functions.sh; find_mtd_part 0:DUAL_FLAG")) end
-				if not zyxelFlagPartition then
-					logger("Unable to find Dual Boot Flag Partition.")
-					ret.error = 'NO_DUAL_FLAG'
+					newEnvSetting="$bev1p1"
+				fi
+				if ! fw_setenv "$bev1" "$newEnvSetting"; then
+					logger "$(printf "Unable to set firmware environment variable: %s to %s." "$bev1" "$newEnvSetting")"
+					json_init
+					json_add_string 'error' 'ERR_SET_ENV'
+					json_add_array 'args'
+					json_add_string "$bev1"
+					json_add_string "$newEnvSetting"
+					json_close_array
+					json_add_string 'rom_board_name' "$romBoardName"
+					json_dump; json_cleanup;
+					return
+				fi
+			fi
+		fi
+		if [ -n "$bev2" ]; then
+			curEnvSetting="$(fw_printenv -n "${bev2}")"
+			if [ -z "$curEnvSetting" ]; then
+				logger "$(printf "Unable to obtain firmware environment variable: %s." "$bev2")"
+				json_init
+				json_add_string 'error' 'NO_FIRM_ENV'
+				json_add_array 'args'
+				json_add_string "$bev2"
+				json_close_array
+				json_add_string 'rom_board_name' "$romBoardName"
+				json_dump; json_cleanup;
+				return
+			else
+				bev2p1="$bootEnv2Partition1Value"
+				bev2p2="$bootEnv2Partition2Value"
+				if [ "$curEnvSetting" = "$bev2p1" ]; then
+					newEnvSetting="$bev2p2"
 				else
-					zyxelBootFlag = tonumber(util.exec("dd if=" .. zyxelFlagPartition .. " bs=1 count=1 2>/dev/null | hexdump -n 1 -e '1/1 \"%d\"'"))
-					zyxelNewBootFlag = zyxelBootFlag and zyxelBootFlag == 1 and "\\xff" or "\\x01"
-					if zyxelNewBootFlag then
-						errorCode = sys.call("printf \"" .. zyxelNewBootFlag .. "\" >" .. zyxelFlagPartition )
-						if errorCode ~= 0 then
-							logger(string.format("Unable to set Dual Boot Flag Partition entry for partition: %s.", zyxelFlagPartition))
-							ret.error = 'ERR_SET_DUAL_FLAG'
-							ret.args = { zyxelFlagPartition }
-							return ret
-						end
-					end
-				end
-			end
-
-			return ret
-		end
-	}
+					newEnvSetting="$bev2p1"
+				fi
+				if ! fw_setenv "$bev2" "$newEnvSetting"; then
+					logger "$(printf "Unable to set firmware environment variable: %s to %s." "$bev2" "$newEnvSetting")"
+					json_init
+					json_add_string 'error' 'ERR_SET_ENV'
+					json_add_array 'args'
+					json_add_string "$bev2"
+					json_add_string "$newEnvSetting"
+					json_close_array
+					json_add_string 'rom_board_name' "$romBoardName"
+					json_dump; json_cleanup;
+					return
+				fi
+			fi
+		fi
+		json_init
+		json_dump; json_cleanup;
+	else # NetGear device
+		if [ -z "$zyxelFlagPartition" ]; then
+			zyxelFlagPartition="$(find_mtd_part 0:DUAL_FLAG 2>/dev/null)"
+		fi
+		if [ -z "$zyxelFlagPartition" ]; then
+			logger "Unable to find Dual Boot Flag Partition."
+			print_json 'error' 'NO_DUAL_FLAG'
+			return
+		else
+			zyxelBootFlag="$(dd if="${zyxelFlagPartition}" bs=1 count=1 2>/dev/null | hexdump -n 1 -e '1/1 "%d"')"
+			if [ "$zyxelBootFlag" = "1" ]; then
+				zyxelNewBootFlag="\\xff"
+			else
+				zyxelNewBootFlag="\\x01"
+			fi
+			if [ -n "$zyxelNewBootFlag" ]; then
+				if ! printf "%b" "$zyxelNewBootFlag" > "$zyxelFlagPartition"; then
+					logger "$(printf "Unable to set Dual Boot Flag Partition entry for partition: %s." "$zyxelFlagPartition")"
+					json_init
+					json_add_string 'error' 'ERR_SET_DUAL_FLAG'
+					json_add_array 'args'
+					json_add_string "$zyxelFlagPartition"
+					json_close_array
+					json_add_string 'rom_board_name' "$romBoardName"
+					json_dump; json_cleanup;
+					return
+				fi
+			fi
+		fi
+		json_init
+		json_dump; json_cleanup;
+	fi
 }
 
-local function parseInput()
-	local parse = json.new()
-	local done, err
-
-	while true do
-		local chunk = io.read(4096)
-		if not chunk then
-			break
-		elseif not done and not err then
-			done, err = parse:parse(chunk)
-		end
-	end
-
-	if not done then
-		print(json.stringify({ error = err or "Incomplete input" }))
-		os.exit(1)
-	end
-
-	return parse:get()
-end
-
-local function validateArgs(func, uargs)
-	local method = methods[func]
-	if not method then
-		print(json.stringify({ error = "Method not found" }))
-		os.exit(1)
-	end
-
-	if type(uargs) ~= "table" then
-		print(json.stringify({ error = "Invalid arguments" }))
-		os.exit(1)
-	end
-
-	uargs.ubus_rpc_session = nil
-
-	local k, v
-	local margs = method.args or {}
-	for k, v in pairs(uargs) do
-		if margs[k] == nil or
-		   (v ~= nil and type(v) ~= type(margs[k]))
-		then
-			print(json.stringify({ error = "Invalid arguments" }))
-			os.exit(1)
-		end
-	end
-
-	return method
-end
-
-if arg[1] == "list" then
-	local _, method, rv = nil, nil, {}
-	for _, method in pairs(methods) do rv[_] = method.args or {} end
-	print((json.stringify(rv):gsub(":%[%]", ":{}")))
-elseif arg[1] == "call" then
-	local args = parseInput()
-	local method = validateArgs(arg[2], args)
-	local result, code = method.call(args)
-	print((json.stringify(result):gsub("^%[%]$", "{}")))
-	os.exit(code or 0)
-end
+case "$1" in
+	list)
+		json_init
+		json_add_object "obtain_device_info"
+		json_close_object
+		json_add_object "toggle_boot_partition"
+		json_close_object
+		json_dump
+		json_cleanup
+		;;
+	call)
+		case "$2" in
+			obtain_device_info)
+				obtain_device_info;;
+			toggle_boot_partition)
+				toggle_boot_partition;;
+		esac
+	;;
+esac