OpenWRT LED Animation | Lua

--[[
    ####--------------------------------####
    #--# Author:   by uriid1            #--#
    #--# License:  GNU GPLv3            #--#
    #--# Telegram: @main_moderator      #--#
    #--# E-mail:   appdurov@gmail.com   #--#
    ####--------------------------------####
--]]

local path = '/sys/class/leds/'
local led = {
    path..'green:power/brightness'; -- 1
    path..'green:wlan/brightness';  -- 2
    path..'green:lan4/brightness';  -- 3
    path..'green:lan3/brightness';  -- 4
    path..'green:lan2/brightness';  -- 5
    path..'green:lan1/brightness';  -- 6
    path..'green:wan/brightness';   -- 7
    path..'green:usb/brightness';   -- 8
    path..'green:qss/brightness';   -- 9
}

local function set_bright(led, val)
    local fd = io.open(led, 'w')
    fd:write(val)
    fd:close()
end

function sleep(a)
    local sec = os.clock() + a
    while os.clock() < sec do end
end

local function off_all_leds()
    for i = 1, #led do
        set_bright(led[i], 0)
    end
end

local function linear_activate_left(spd)
    for i = 1, #led do
        set_bright(led[i], 255)
        sleep(spd)
    end
end

local function linear_deactivate_left(spd)
    for i = #led, 1, -1 do
        set_bright(led[i], 0)
        sleep(spd)
    end
end

-- Main anim loop
while true do
    off_all_leds()
    linear_activate_left(0.1)
    linear_deactivate_left(0.1)
end