dcron: systemd support

Signed-off-by: Alex Suykov <alex.suykov@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/dcron/dcron.mk

@@ -33,4 +33,12 @@ define DCRON_INSTALL_INIT_SYSV
 	$(INSTALL) -D -m 0755 package/dcron/S90dcron $(TARGET_DIR)/etc/init.d/S90dcron
 endef
 
+define DCRON_INSTALL_INIT_SYSTEMD
+	$(INSTALL) -D -m 644 package/dcron/dcron.service \
+		$(TARGET_DIR)/usr/lib/systemd/system/dcron.service
+	mkdir -p $(TARGET_DIR)/etc/systemd/system/multi-user.target.wants
+	ln -sf /usr/lib/systemd/system/dcron.service \
+		$(TARGET_DIR)/etc/systemd/system/multi-user.target.wants/dcron.service
+endef
+
 $(eval $(generic-package))

package/dcron/dcron.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Task scheduler daemon
+After=syslog.target
+
+[Service]
+ExecStart=/usr/sbin/crond -f -S
+Restart=always
+
+[Install]
+WantedBy=multi-user.target