ffho-packages/ffho/ffho-autoupdater-wifi-fallback/files/usr/sbin/autoupdater-wifi-fallback

#!/usr/bin/lua
local fs = require('nixio.fs')
local uci = require('luci.model.uci').cursor()
local site = require 'gluon.site_config'
local util = require 'luci.util'
local ut = require('autoupdater-wifi-fallback.util')
local gluon = require 'gluon.util'

local configname = 'autoupdater-wifi-fallback'
local force = false
local min_uptime_secs = 3600
local branch_name = uci:get('autoupdater','settings','branch')

local function parse_args()
local i = 1
  while arg[i] do
    if arg[i] == '-f' then
      force = true
    elseif arg[i] == '-b' then
      i=i+1

      if not arg[i] then
        io.stderr:write("Error parsing command line: expected branch name\n")
        os.exit(1)
      end

      branch_name = arg[i]
    else
      io.stderr:write("Error parsing command line: unexpected argument '" .. arg[i] .. "'\n")
      os.exit(1)
    end
    i = i+1
  end
end

local function preflight_check()
  if not uci:get_bool(configname,'settings','enabled') then
    return false
  end
  if not uci:get_bool('autoupdater','settings','enabled') then
    return false
  end
  if tonumber(fs.readfile('/proc/uptime'):match('^([^ ]+) ')) < min_uptime_secs then
    return false
  end

  return true
end

local function connectivity_check()
  local f = io.open('/sys/kernel/debug/batman_adv/bat0/gateways', 'r')
  if f then
    for line in f:lines() do
      local gateway_mac = line:match("^=?>? +([0-9a-f:]+)")
      if gateway_mac then
        if os.execute("batctl ping -t5 -c1 " .. gateway_mac .. " > /dev/null 2>&1") == 0 then
          return true
        end
      end
    end
    f:close()
  end
  
  -- connectivity check against updateserver
  for _, host in ipairs(get_update_hosts(branch_name)) do
    if os.execute("ping -w2 -c1 " .. host .. " > /dev/null 2>&1") == 0 then
      return true
    end
  end

  io.popen('logger -s -t autoupdater-wifi-fallback -p local0.info "connectivity check failed"')
  return false
end

local function run_autoupdater()
  io.popen('logger -s -t autoupdater-wifi-fallback -p local0.info "execute the autoupdater"')
  os.execute("/usr/sbin/autoupdater -f -b " .. branch_name)
end

local function switch_to_fallback_mode(radio, ssid, bssid)
  io.popen('logger -s -t autoupdater-wifi-fallback -p local0.info "connect to '  .. radio .. ' ' .. ssid .. ' ' .. bssid .. '"')
  uci:delete_all('wireless', 'wifi-iface')
  uci:section('wireless', 'wifi-iface', 'fallback',
    {
      device = radio,
      network = 'fallback',
      mode = 'sta',
      disabled = 0,
      macaddr = gluon.generate_mac(3, 10),
      bssid = bssid,
      ssid = ssid,
      ifname = 'fallback',
      encryption = 'none',
    }
  )
  uci:set('wireless', radio, 'disabled', 0)
  uci:save('wireless')

  os.execute("wifi")
  os.execute("sleep 5")
  uci:revert('wireless')
  os.execute("sleep 20")
end

local function revert_to_standard_mode()
  io.popen('logger -s -t autoupdater-wifi-fallback -p local0.info "going back to standard mode"')
  os.execute("/etc/init.d/network restart")
  os.execute("sleep 30")
end

parse_args()

if not uci:get('autoupdater', branch_name) then
  io.stderr:write("Can't find configuration for branch '" .. branch_name .. "'\n")
  os.exit(1)
end

if (force or preflight_check()) and not connectivity_check() then
  local offset = 2 * 3600
  local unreachable_since = os.time()
  if not uci:get('autoupdater-wifi-fallback', 'settings', 'unreachable_since') then
    uci:set(configname, 'settings', 'unreachable_since', unreachable_since)
  else
    uci:set(configname, 'settings', 'last_run', unreachable_since)
    unreachable_since = uci:get(configname, 'settings', 'unreachable_since')
  end
  uci:save(configname)
  
  if force or tonumber(unreachable_since) + offset < os.time() then
    io.popen('logger -s -t autoupdater-wifi-fallback -p local0.info "going to fallback mode"')
    local radio, ssid, bssid = get_available_wifi_networks()
    if radio and ssid and bssid then
      switch_to_fallback_mode(radio, ssid, bssid)
      run_autoupdater()
      -- this is only reached if no updated happened
      revert_to_standard_mode()
    end
  end
else
  uci:delete(configname, 'settings','unreachable_since')
  uci:delete(configname, 'settings','last_run')
  uci:save(configname)
end