systemd.bbclass: Make systemd_postinst run as intended

After the switch from using a systemctl written in Python to using the
official version of systemctl from the systemd project, the
systemd_postinst function has effectively not been executed during the
rootfs creation. The reason is that systemctl provided by
systemctl-native fails if run without arguments (as systemd_postinst
does):

  Failed to connect to system scope bus via local transport: Operation
  not permitted (consider using --machine=<user>@.host --user to connect
  to bus of other user)

This is not seen in the logs since stderr is sent to /dev/null, and the
only way to tell that there is a problem is because systemd services
that are expected to be enabled aren't running.

The reason this has gone unnoticed is because systemd_handle_machine_id
in rootfs-postcommands.bbclass will call systemctl preset-all, which in
most cases will create the missing links to enable the systemd services.

This change effectively reverts commit
a52e66762c0c51918b1ba3d4622759637b6e920a (systemd.bbclass: update
command to check systemctl available) and instead only runs systemctl
without arguments (to determine that it can communicate with systemd)
when executed on target.

(From OE-Core rev: 5b86efb5c9ca782fd0f8ff306f82583ec1e5e909)

Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/meta/classes-recipe/systemd.bbclass b/meta/classes-recipe/systemd.bbclass
index 0e9f7cfa33..4e687135f1 100644
--- a/meta/classes-recipe/systemd.bbclass
+++ b/meta/classes-recipe/systemd.bbclass
@@ -29,7 +29,7 @@ python __anonymous() {
 }
 
 systemd_postinst() {
-if systemctl >/dev/null 2>/dev/null; then
+if type systemctl >/dev/null 2>/dev/null; then
         OPTS=""
 
         if [ -n "$D" ]; then
@@ -46,7 +46,7 @@ if systemctl >/dev/null 2>/dev/null; then
                 done
         fi
 
-        if [ -z "$D" ]; then
+        if [ -z "$D" ] && systemctl >/dev/null 2>/dev/null; then
                 # Reload only system service manager
                 # --global for daemon-reload is not supported: https://github.com/systemd/systemd/issues/19284
                 systemctl daemon-reload
@@ -66,8 +66,8 @@ fi
 }
 
 systemd_prerm() {
-if systemctl >/dev/null 2>/dev/null; then
-        if [ -z "$D" ]; then
+if type systemctl >/dev/null 2>/dev/null; then
+        if [ -z "$D" ] && systemctl >/dev/null 2>/dev/null; then
                 if [ -n "${@systemd_filter_services("${SYSTEMD_SERVICE_ESCAPED}", False, d)}" ]; then
                         systemctl stop ${@systemd_filter_services("${SYSTEMD_SERVICE_ESCAPED}", False, d)}
                         systemctl disable ${@systemd_filter_services("${SYSTEMD_SERVICE_ESCAPED}", False, d)}