[oe] [meta-networking][PATCH v3] dnsmasq: get systemd only working again

[Joe MacDonald]

From: Mark Asselstine <mark.asselstine at windriver.com>

The changes made in commit 2497cf2960537152427c99629b2af412787eb6c2
[dnsmasq: steal resolvconf support from Ubuntu] broke systemd only
dnsmasq runtime. No sysvinit scripts are included in systemd only
builds (and should not be) and the dnsmasq executable has not moved to
/usr/sbin.

Reverting to the previous version of the systemd service file. If
folks want the local dnsmasq instance to be queried before going to
an external DNS they should add 'nameserver 127.0.0.1' to
/etc/resolv.conf. Or submit a change which will work with systemd.

Signed-off-by: Mark Asselstine <mark.asselstine at windriver.com>
Signed-off-by: Joe MacDonald <joe_macdonald at mentor.com>
---

The previous one should've been v2, so I've named this one v3 explicitly.
After reading more of the systemd documentation I think this approach in
the service file is the current best option available.  It would certainly
be cleaner to store the pidfile name in an environment variable but it
turns out on further inspection that if you pass a varaible to PIDFile,
you get errors (that you only see when the service is stopped, not while
it is running) indicating essentially that it is falling back to the
"guess the MAINPID value" behaviour.  So this seems to be the way we're
supposed to do this type of thing now.

-J.

 .../recipes-support/dnsmasq/dnsmasq.inc            |  9 ++--
 .../dnsmasq/files/dnsmasq-resolvconf-helper        | 62 ++++++++++++++++++++++
 .../recipes-support/dnsmasq/files/dnsmasq.service  |  9 ++--
 3 files changed, 72 insertions(+), 8 deletions(-)
 create mode 100644 meta-networking/recipes-support/dnsmasq/files/dnsmasq-resolvconf-helper

diff --git a/meta-networking/recipes-support/dnsmasq/dnsmasq.inc b/meta-networking/recipes-support/dnsmasq/dnsmasq.inc
index 622e630..df58e5c 100644
--- a/meta-networking/recipes-support/dnsmasq/dnsmasq.inc
+++ b/meta-networking/recipes-support/dnsmasq/dnsmasq.inc
@@ -60,11 +60,12 @@ do_install () {
         install -m 644 dbus/dnsmasq.conf ${D}${sysconfdir}/dbus-1/system.d/
     fi
     if [ "${@base_contains('PACKAGECONFIG', 'resolvconf', 'resolvconf', '', d)}" != "" ]; then
-	install -d ${D}${sysconfdir}/resolvconf/update.d/
-	install -m 0755 ${WORKDIR}/dnsmasq.resolvconf ${D}${sysconfdir}/resolvconf/update.d/dnsmasq
+        install -d ${D}${sysconfdir}/resolvconf/update.d/
+        install -m 0755 ${WORKDIR}/dnsmasq.resolvconf ${D}${sysconfdir}/resolvconf/update.d/dnsmasq
 
-	install -d ${D}${sysconfdir}/default/volatiles
-	install -m 0644 ${WORKDIR}/99_dnsmasq ${D}${sysconfdir}/default/volatiles
+        install -d ${D}${sysconfdir}/default/volatiles
+        install -m 0644 ${WORKDIR}/99_dnsmasq ${D}${sysconfdir}/default/volatiles
+        install -m 0755 ${WORKDIR}/dnsmasq-resolvconf-helper ${D}${bindir}
     fi
 }
 
diff --git a/meta-networking/recipes-support/dnsmasq/files/dnsmasq-resolvconf-helper b/meta-networking/recipes-support/dnsmasq/files/dnsmasq-resolvconf-helper
new file mode 100644
index 0000000..db54d46
--- /dev/null
+++ b/meta-networking/recipes-support/dnsmasq/files/dnsmasq-resolvconf-helper
@@ -0,0 +1,62 @@
+#!/bin/bash
+#
+# Borrowing heavily from the dnsmasq initscript's version of support for
+# resolvconf, intended for use in systemd-only configurations.
+#
+PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
+DAEMON=/usr/sbin/dnsmasq
+NAME=dnsmasq
+
+# Most configuration options in /etc/default/dnsmasq are deprecated
+# but still honoured.
+if [ -r /etc/default/$NAME ]; then
+   . /etc/default/$NAME
+fi
+
+start_resolvconf()
+{
+   # If interface "lo" is explicitly disabled in /etc/default/dnsmasq
+   # Then dnsmasq won't be providing local DNS, so don't add it to
+   # the resolvconf server set.
+   for interface in $DNSMASQ_EXCEPT
+   do
+      [ $interface = lo ] && return
+   done
+
+   if [ -x /sbin/resolvconf ] ; then
+      echo "nameserver 127.0.0.1" |
+      /sbin/resolvconf -a lo.$NAME
+   fi
+   return 0
+}
+
+stop_resolvconf()
+{
+   if [ -x /sbin/resolvconf ] ; then
+      /sbin/resolvconf -d lo.$NAME
+   fi
+   return 0
+}
+
+case "$1" in
+   start)
+      start_resolvconf
+      exit 0
+      ;;
+   stop)
+      stop_resolvconf
+      exit 0
+      ;;
+   restart)
+      stop_resolvconf
+      start_resolvconf
+      exit 0
+      ;;
+   *)
+      echo "Usage: /etc/init.d/$NAME {start|stop|restart}" >&2
+      exit 3
+      ;;
+esac
+
+exit 0
+
diff --git a/meta-networking/recipes-support/dnsmasq/files/dnsmasq.service b/meta-networking/recipes-support/dnsmasq/files/dnsmasq.service
index c3637e1..68b175c 100644
--- a/meta-networking/recipes-support/dnsmasq/files/dnsmasq.service
+++ b/meta-networking/recipes-support/dnsmasq/files/dnsmasq.service
@@ -5,10 +5,11 @@ After=network.target
 [Service]
 Type=forking
 PIDFile=/run/dnsmasq.pid
-ExecStartPre=/usr/sbin/dnsmasq --test
-ExecStart=/etc/init.d/dnsmasq systemd-exec
-ExecStartPost=/etc/init.d/dnsmasq systemd-start-resolvconf
-ExecStopPre=/etc/init.d/dnsmasq systemd-stop-resolvconf
+ExecStartPre=/usr/bin/dnsmasq --test
+ExecStart=/usr/bin/dnsmasq -x /run/dnsmasq.pid
+ExecStartPost=/usr/bin/dnsmasq-resolvconf-helper start
+ExecStopPre=/usr/bin/dnsmasq-resolvconf-helper stop
+ExecStop=/bin/kill $MAINPID
 ExecReload=/bin/kill -HUP $MAINPID
 
 [Install]
-- 
1.9.1