pacman_unrequired_packages: new plugin

Heavily based on pacman_pending_updates

plugins/other/pacman_unrequired_packages

@@ -0,0 +1,81 @@
+#!/bin/sh
+
+: <<=cut
+
+=head1 NAME
+
+pacman_unrequired_packages - Plugin to monitor packages no longer required.
+
+=head1 APPLICABLE SYSTEMS
+
+All systems with pacman as their package manager.
+
+=head1 CONFIGURATION
+
+The plugin needs no additional configuration and works out of the box.
+
+=head1 INTERPRETATION
+
+This plugin will draw one block: the number of packages no longer required.
+
+=head1 MAGIC MARKERS
+
+  #%# family=auto
+  #%# capabilities=autoconf
+
+=head1 VERSION
+
+  1.0.0
+
+=head1 AUTHOR
+
+Olivier Mehani <shtrom+munin@ssji.net>
+Bert Peters <bert@bertptrs.nl> (pacman_pending_updates)
+
+=head1 LICENSE
+
+GPLv2
+
+=cut
+
+case $1 in
+	config)
+		cat <<'EOM'
+graph_args --base 1000 -l 0
+graph_title Unrequired packages
+graph_vlabel packages
+graph_category security
+unrequired.label unrequired
+unrequired.info Current number of unrequired packages. They can be removed with `pacman -Rsn $(pacman -Qdtq).` 
+unrequired.draw AREA
+EOM
+		;;
+
+	autoconf)
+		if hash pacman >/dev/null 2>&1; then
+			echo yes
+		else
+			echo "no (pacman not found)"
+		fi
+		;;
+
+	*)
+		unrequired="$(pacman -Qdtq)"
+		exitcode=$?
+		if [ "$exitcode" = 0 ]; then
+			if [ -n "$unrequired" ]; then
+				echo "unrequired.value $(echo "$unrequired" | wc -l)"
+				echo "unrequired.extinfo $(echo "$unrequired" | paste -s -d,)"
+			else
+				echo "unrequired.value 0"
+			fi
+		elif [ "$exitcode" = 1 ]; then
+			# "pacman" returns the exitcode 1 if no matching package is found
+			echo "unrequired.value 0"
+		else
+			echo "unrequired.value U"
+		fi
+		;;
+esac
+
+exit 0