collectd may fail to start in wheezy if processes-plugin is used with…

…out any process

manifests/plugin/processes.pp

@@ -17,28 +17,33 @@
     interval => $interval,
   }
 
+  if ( $processes or $process_matches ) {
+    $process_config_ensure = present
+  } else {
+    $process_config_ensure = absent
+  }
+
   concat{"${collectd::params::plugin_conf_dir}/processes-config.conf":
-    ensure         => $ensure,
+    ensure         => $process_config_ensure,
     mode           => '0640',
     owner          => 'root',
     group          => $collectd::params::root_group,
     notify         => Service['collectd'],
     ensure_newline => true,
   }
   concat::fragment{'collectd_plugin_processes_conf_header':
-    ensure  => $ensure,
+    ensure  => $process_config_ensure,
     order   => '00',
     content => '<Plugin processes>',
     target  => "${collectd::params::plugin_conf_dir}/processes-config.conf",
   }
   concat::fragment{'collectd_plugin_processes_conf_footer':
-    ensure  => $ensure,
+    ensure  => $process_config_ensure,
     order   => '99',
     content => '</Plugin>',
     target  => "${collectd::params::plugin_conf_dir}/processes-config.conf",
   }
 
-
   if $processes {
     collectd::plugin::processes::process { $processes : }
   }