al-skel/home/.config/awesome/vicious/widgets/volume.lua

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-- Licensed under the GNU General Public License v2
--  * (c) 2010, Adrian C. <anrxc@sysphere.org>
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-- {{{ Grab environment
local tonumber = tonumber
local io = { popen = io.popen }
local setmetatable = setmetatable
local string = { match = string.match }
local helpers = require("vicious.helpers")
-- }}}


-- Volume: provides volume levels and state of requested ALSA mixers
-- vicious.widgets.volume
local volume = {}


-- {{{ Volume widget type
local function worker(format, warg)
  if not warg then return end

  local mixer_state = {
    ["on"]  = "♫", -- "",
    ["off"] = "♩"  -- "M"
  }

  -- Get mixer control contents
  local f = io.popen("amixer -M get " .. helpers.shellquote(warg))
  local mixer = f:read("*all")
  f:close()

  -- Capture mixer control state:          [5%] ... ... [on]
  local volu, mute = string.match(mixer, "([%d]+)%%.*%[([%l]*)")
  -- Handle mixers without data
  if volu == nil then
    return {0, mixer_state["off"]}
  end

  -- Handle mixers without mute
  if mute == "" and volu == "0"
  -- Handle mixers that are muted
  or mute == "off" then
    mute = mixer_state["off"]
  else
    mute = mixer_state["on"]
  end

  return {tonumber(volu), mute}
end
-- }}}

return setmetatable(volume, { __call = function(_, ...) return worker(...) end })