Ensure we calculate the true systemd unit name.

When passing just a sysvinit name, we synthesise a systemd unit name via
the amazingly cunning and subtle technique of adding '.service' on to the
name.

This is very effective for referring to units for most commands as even if
an actual unit file of this name exists systemd might be providing the
unit for this service via a different name, but just symlinking to the
sysvinit name in order to prevent the sysvinit script from firing.

This is done with e.g. the dm and networkmanager services.

When using the symlinked name, systemctl will refuse to enable or disable
the unit (see https://bugs.mageia.org/show_bug.cgi?id=3188) and this is
expected behaviour.

Thus we use readlink to attempt to resolve the link to a real name.

1 files changed, 20 insertions, 0 deletions

diff --git a/add-service b/add-service
index 1b5ac54..26bc04e 100755
--- a/add-service
+++ b/add-service
@@ -46,6 +46,26 @@ units_to_enable=		# units enabled by msec
 # catch the most common usage.
 if [ -z "$units" ]; then
   units="$srv.service"
+
+  # We need to normalise the systemd unit name as the native unit may not have
+  # the same filename (sans it's .service suffix) as sysvinit script.
+  # In this case, symlinks are used to mask the sysvinit file, but for enabling
+  # and disabling units we must use the official name.
+  SYSTEMUNITDIR=/lib/systemd/system
+  USERUNITDIR=/etc/systemd/system
+  RUNTIMEUNITDIR=/run/systemd/system
+
+  searchunit=
+  if [ -f "$SYSTEMUNITDIR/$units" ]; then
+    searchunit=$(/usr/bin/readlink "$SYSTEMUNITDIR/$units")
+  elif [ -f "$USERUNITDIR/$units" ]; then
+    searchunit=$(/usr/bin/readlink "$USERUNITDIR/$units")
+  elif [ -f "$RUNTIMEUNITDIR/$units" ]; then
+    searchunit=$(/usr/bin/readlink "$RUNTIMEUNITDIR/$units")
+  fi
+  if [ -n "$searchunit" ]; then
+    units=$searchunit
+  fi
 fi
 
 add_service() {