volume: move volume functions into a lib

Also add some notification when changing the volume. Also move
sharetags to the `lib/` directory. And modify `loadrc` to be able to
load modules.

lib/volume.lua

@@ -0,0 +1,52 @@
+-- Handle volume (through pulseaudio)
+
+local awful        = require("awful")
+local naughty      = require("naughty")
+local tonumber     = tonumber
+local string       = string
+local os           = os
+local setmetatable = setmetatable
+
+module("volume")
+
+local volid = nil
+local function change(what)
+   os.execute("amixer -q sset Master " .. what, false)
+   -- Read the current value
+   local out = awful.util.pread("amixer sget Master")
+   local vol, mute = out:match("([%d]+)%%.*%[([%l]*)")
+   if not mute or not vol then return end
+
+   vol = tonumber(vol)
+   local icon = "high"
+   if mute ~= "on" or vol == 0 then
+      icon = "muted"
+   elseif vol < 30 then
+      icon = "low"
+   elseif vol < 60 then
+      icon = "medium"
+   end
+   icon = "/usr/share/icons/gnome/32x32/status/audio-volume-" .. icon .. ".png"
+
+   volid = naughty.notify({ text = string.format("%3d %%", vol),
+			    icon = icon,
+			    font = "Free Sans Bold 24",
+			    replaces_id = volid }).id
+end
+
+function increase()
+   change("5%+")
+end
+
+function decrease()
+   change("5%-")
+end
+
+function toggle()
+   change("toggle")
+end
+
+-- run pavucontrol
+function mixer()
+   awful.util.spawn("pavucontrol", false)
+end

rc.lua

@@ -5,10 +5,19 @@ require("beautiful")
 require("naughty")
 
 -- Simple function to load additional LUA files from rc/.
-function loadrc(name)
+function loadrc(name, mod)
    local success
    local result
-   local path = awful.util.getdir("config") .. "/rc/" .. name .. ".lua"
+
+   -- Which file? In rc/ or in lib/?
+   local path = awful.util.getdir("config") .. "/" ..
+      (mod and "lib" or "rc") ..
+      "/" .. name .. ".lua"
+
+   -- If the module is already loaded, don't load it again
+   if mod and package.loaded[mod] then return package.loaded[mod] end
+
+   -- Execute the RC/module file
    success, result = pcall(function() return dofile(path) end)
    if not success then
       naughty.notify({ title = "Error while loading an RC file",
@@ -18,6 +27,12 @@ function loadrc(name)
 		     })
       return print("E: error loading RC file '" .. name .. "': " .. result)
    end
+
+   -- Is it a module?
+   if mod then
+      return package.loaded[mod]
+   end
+
    return result
 end
 

rc/bindings.lua

@@ -1,5 +1,6 @@
 config.keys = {}
 config.mouse = {}
+local volume = loadrc("volume", "volume")
 
 local function client_info()
     local v = ""
@@ -79,9 +80,9 @@ config.keys.global = awful.util.table.join(
    awful.key({ modkey, "Control" }, "r", awesome.restart),
 
    -- Multimedia keys
-   awful.key({ }, "XF86AudioRaiseVolume", function () awful.util.spawn("amixer -q -c 0 set Master 2dB+", false) end),
-   awful.key({ }, "XF86AudioLowerVolume", function () awful.util.spawn("amixer -q -c 0 set Master 2dB-", false) end),
-   awful.key({ }, "XF86AudioMute", function () awful.util.spawn("amixer -q -c 0 set Master toggle", false) end)
+   awful.key({ }, "XF86AudioRaiseVolume", volume.increase),
+   awful.key({ }, "XF86AudioLowerVolume", volume.decrease),
+   awful.key({ }, "XF86AudioMute",        volume.toggle)
 )
 
 config.keys.client = awful.util.table.join(

rc/tags.lua

@@ -1,6 +1,6 @@
 -- Tags
 
-loadrc("sharetags")
+sharetags = loadrc("sharetags", "sharetags")
 
 local otags = config.tags
 config.tags = {}

rc/widgets.lua

@@ -105,12 +105,12 @@ local volwidget = widget({ type = "textbox" })
 vicious.register(volwidget, vicious.widgets.volume,
 		 '<span font="Terminus 8" color="' .. beautiful.fg_widget_value .. '">$2 $1%</span>',
 		2, "Master")
+volume = loadrc("volume", "volume")
 volwidget:buttons(awful.util.table.join(
-   awful.button({ }, 1, function () awful.util.spawn("pavucontrol", false) end),
-   awful.button({ }, 3, function () awful.util.spawn("amixer -q sset Master toggle", false) end),
-   awful.button({ }, 4, function () awful.util.spawn("amixer -q sset Master 5%+", false) end),
-   awful.button({ }, 5, function () awful.util.spawn("amixer -q sset Master 5%-", false) end)
-))
+		     awful.button({ }, 1, volume.mixer),
+		     awful.button({ }, 3, volume.toggle),
+		     awful.button({ }, 4, volume.increase),
+		     awful.button({ }, 5, volume.decrease)))
 
 -- File systems
 local fs = { ["/"] = "root",