[oe] [meta-networking][PATCH] networkmanager: Use ALTERNATIVES for resolv-conf handling.

[drew.moseley at northern.tech]

From: Drew Moseley <drew.moseley at northern.tech>

This brings the networkmanager in sync with how systemd-resolved and connman
work. Additionally this allows it to function with a read-only rootFS.

Signed-off-by: Drew Moseley <drew.moseley at northern.tech>
---
 .../networkmanager/networkmanager_1.18.0.bb          | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/meta-networking/recipes-connectivity/networkmanager/networkmanager_1.18.0.bb b/meta-networking/recipes-connectivity/networkmanager/networkmanager_1.18.0.bb
index 21fbea9c1..037566783 100644
--- a/meta-networking/recipes-connectivity/networkmanager/networkmanager_1.18.0.bb
+++ b/meta-networking/recipes-connectivity/networkmanager/networkmanager_1.18.0.bb
@@ -20,7 +20,7 @@ DEPENDS = " \
     curl \
 "
 
-inherit gnomebase gettext systemd bash-completion vala gobject-introspection gtk-doc
+inherit gnomebase gettext systemd bash-completion vala gobject-introspection gtk-doc update-alternatives
 
 SRC_URI = " \
     ${GNOME_MIRROR}/NetworkManager/${@gnome_verdir("${PV}")}/NetworkManager-${PV}.tar.xz \
@@ -141,6 +141,16 @@ FILES_${PN}-nmtui-doc = " \
 
 SYSTEMD_SERVICE_${PN} = "${@bb.utils.contains('PACKAGECONFIG', 'systemd', 'NetworkManager.service NetworkManager-dispatcher.service', '', d)}"
 
+ALTERNATIVE_PRIORITY = "100"
+ALTERNATIVE_${PN} = "${@bb.utils.contains('DISTRO_FEATURES','systemd','resolv-conf','',d)}"
+ALTERNATIVE_TARGET[resolv-conf] = "${@bb.utils.contains('DISTRO_FEATURES','systemd','${sysconfdir}/resolv-conf.NetworkManager','',d)}"
+ALTERNATIVE_LINK_NAME[resolv-conf] = "${@bb.utils.contains('DISTRO_FEATURES','systemd','${sysconfdir}/resolv.conf','',d)}"
+
 do_install_append() {
     rm -rf ${D}/run ${D}${localstatedir}/run
+
+    # For read-only filesystem, do not create links during bootup
+    if ${@bb.utils.contains('DISTRO_FEATURES','systemd','true','false',d)}; then
+        ln -sf ../run/NetworkManager/resolv.conf ${D}${sysconfdir}/resolv-conf.NetworkManager
+    fi
 }
-- 
2.22.0