diff --git a/functions-common b/functions-common
index 52d80fb..ff92611 100644
--- a/functions-common
+++ b/functions-common
@@ -1629,7 +1629,6 @@
 function disable_negated_services {
     local to_remove=""
     local remaining=""
-    local enabled=""
     local service
 
     # build up list of services that should be removed; i.e. they
@@ -1644,21 +1643,7 @@
 
     # go through the service list.  if this service appears in the "to
     # be removed" list, drop it
-    for service in ${remaining//,/ }; do
-        local remove
-        local add=1
-        for remove in ${to_remove//,/ }; do
-            if [[ ${remove} == ${service} ]]; then
-                add=0
-                break
-            fi
-        done
-        if [[ $add == 1 ]]; then
-            enabled="${enabled},$service"
-        fi
-    done
-
-    ENABLED_SERVICES=$(_cleanup_service_list "$enabled")
+    ENABLED_SERVICES=$(remove_disabled_services "$remaining" "$to_remove")
 }
 
 # disable_service() removes the services passed as argument to the
@@ -1762,6 +1747,30 @@
     return $enabled
 }
 
+# remove specified list from the input string
+# remove_disabled_services service-list remove-list
+function remove_disabled_services {
+    local service_list=$1
+    local remove_list=$2
+    local service
+    local enabled=""
+
+    for service in ${service_list//,/ }; do
+        local remove
+        local add=1
+        for remove in ${remove_list//,/ }; do
+            if [[ ${remove} == ${service} ]]; then
+                add=0
+                break
+            fi
+        done
+        if [[ $add == 1 ]]; then
+            enabled="${enabled},$service"
+        fi
+    done
+    _cleanup_service_list "$enabled"
+}
+
 # Toggle enable/disable_service for services that must run exclusive of each other
 #  $1 The name of a variable containing a space-separated list of services
 #  $2 The name of a variable in which to store the enabled service's name