Add volume control script

Sometimes the built-in keys stop controlling the active volume source
(they're probably bound to the internal speakers?). This script+cwm
configuration fixes that.

.cwmrc

@@ -34,6 +34,10 @@ bind-key XF86AudioPlay	"playerctl play-pause"
 bind-key XF86AudioNext	"playerctl previous"
 bind-key XF86AudioPrev	"playerctl next"
 
+bind-key XF86AudioRaiseVolume "volctl raise"
+bind-key XF86AudioLowerVolume "volctl lower"
+bind-key XF86AudioMute "volctl toggle-mute"
+
 bind-mouse 4-1		window-move
 bind-mouse 4-2		window-close
 bind-mouse 4-3		window-resize

.local/bin/volctl

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+action=$1
+
+if [ "$action" = "raise" ]; then
+	sndioctl output.level=+0.05
+elif [ "$action" = "lower" ]; then
+	sndioctl output.level=-0.05
+elif [ "$action" = "toggle-mute" ]; then
+	sndioctl output.mute=!
+else
+	echo "volctl: unknown action: $1"
+fi