[OE-core] [PATCH v3 3/5] systemd: create preset files instead of installing in image

[Jonas Bonn]

At first boot, systemd will create the /etc/systemd/system directory
from service preset files.  As such, for a normal, writable /etc
(writable rootfs), there is no need to set up this directory at image
creation time.

This patch changes the systemd machinery to create preset files and to
rely on systemd to do the service enablement.

This breaks the read-only-rootfs case; there's a fix for this in a
follow-up patch.

Signed-off-by: Jonas Bonn <jonas at norrbonn.se>
---
 meta/classes/systemd.bbclass | 33 ++++++++++++++++-----------------
 1 file changed, 16 insertions(+), 17 deletions(-)

diff --git a/meta/classes/systemd.bbclass b/meta/classes/systemd.bbclass
index c8f4fdec88..403d2108df 100644
--- a/meta/classes/systemd.bbclass
+++ b/meta/classes/systemd.bbclass
@@ -16,43 +16,32 @@ python __anonymous() {
     # from doing any work so that pure-systemd images don't have redundant init
     # files.
     if bb.utils.contains('DISTRO_FEATURES', 'systemd', True, False, d):
-        d.appendVar("DEPENDS", " systemd-systemctl-native")
-        d.appendVar("PACKAGE_WRITE_DEPS", " systemd-systemctl-native")
         if not bb.utils.contains('DISTRO_FEATURES', 'sysvinit', True, False, d):
             d.setVar("INHIBIT_UPDATERCD_BBCLASS", "1")
 }
 
 systemd_postinst() {
-OPTS=""
-
 if [ -n "$D" ]; then
-    OPTS="--root=$D"
+	exit 0
 fi
 
 if type systemctl >/dev/null 2>/dev/null; then
-	if [ -z "$D" ]; then
-		systemctl daemon-reload
-	fi
-
-	systemctl $OPTS ${SYSTEMD_AUTO_ENABLE} ${SYSTEMD_SERVICE_ESCAPED}
+	systemctl daemon-reload
+	systemctl preset ${SYSTEMD_SERVICE_ESCAPED}
 
-	if [ -z "$D" -a "${SYSTEMD_AUTO_ENABLE}" = "enable" ]; then
+	if [ "${SYSTEMD_AUTO_ENABLE}" = "enable" ]; then
 		systemctl --no-block restart ${SYSTEMD_SERVICE_ESCAPED}
 	fi
 fi
 }
 
 systemd_prerm() {
-OPTS=""
-
 if [ -n "$D" ]; then
-    OPTS="--root=$D"
+	exit 0
 fi
 
 if type systemctl >/dev/null 2>/dev/null; then
-	if [ -z "$D" ]; then
-		systemctl stop ${SYSTEMD_SERVICE_ESCAPED}
-	fi
+	systemctl stop ${SYSTEMD_SERVICE_ESCAPED}
 
 	systemctl $OPTS disable ${SYSTEMD_SERVICE_ESCAPED}
 fi
@@ -177,12 +166,22 @@ python systemd_populate_packages() {
                 else:
                     bb.fatal("SYSTEMD_SERVICE_%s value %s does not exist" % (pkg_systemd, service))
 
+    def systemd_create_presets(pkg):
+        action = get_package_var(d, 'SYSTEMD_AUTO_ENABLE', pkg)
+        presetf = oe.path.join(d.getVar("PKGD"), d.getVar("systemd_unitdir"), "system-preset/98-%s.preset" % pkg)
+        bb.utils.mkdirhier(os.path.dirname(presetf))
+        with open(presetf, 'a') as fd:
+            for service in d.getVar('SYSTEMD_SERVICE_%s' % pkg).split():
+                fd.write("%s %s\n" % (action,service))
+        d.appendVar("FILES_%s" % pkg, ' ' + oe.path.join(d.getVar("systemd_unitdir"), "system-preset/98-%s.preset" % pkg))
+
     # Run all modifications once when creating package
     if os.path.exists(d.getVar("D")):
         for pkg in d.getVar('SYSTEMD_PACKAGES').split():
             systemd_check_package(pkg)
             if d.getVar('SYSTEMD_SERVICE_' + pkg):
                 systemd_generate_package_scripts(pkg)
+                systemd_create_presets(pkg)
         systemd_check_services()
 }
 
-- 
2.19.1