From: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
Date: Thu, 9 Jun 2016 19:46:56 +0200
Subject: [PATCH] post-scripts: Enable systemd-binfmt for first boot.

IMPORTANT:
This commit introduces the following file on Fuel Master,
containing the list of arch supported for target nodes:
</etc/fuel_openstack_arch>.

This file is created AFTER pre.d OPNFV scripts are ran, also by
bootstrap_admin_node.sh, BEFORE the post.d scripts are executed.
NOTE: Arch format is the same used by dpkg (e.g.: "amd64 arm64")

Based on the number of foreign architectures we should support
(the list of archs in /etc/fuel_openstack_arch minus native arch),
we determine whether cross-builds are expected, in which case
binfmt support should be functional during first Fuel Master boot.

Since systemd-binfmt service has a series of preconditions for
starting, which are tested early during first boot, some of them
are NOT YET true (e.g. no binfmt handlers are present before
qemu-user-static package is installed), so the service is not
automatically started. Of course, this only affects the first boot.

Finally, this commit adds an OPNFV post-install script in
/opt/opnfv/bootstrap/post.d, which starts systemd-binfmt service.
---
 build/bootstrap_admin_node.sh.patch                | 15 ++++++++++
 .../post-scripts/80_prepare_cross_builds.sh        | 32 ++++++++++++++++++++++
 2 files changed, 47 insertions(+)
 create mode 100755 build/f_isoroot/f_bootstrap/post-scripts/80_prepare_cross_builds.sh

diff --git a/build/patch-repos/0010-bootstrap_admin_node.sh.patch b/build/patch-repos/0010-bootstrap_admin_node.sh.patch
index b1ea90b..7f16d0b 100644
--- a/build/patch-repos/0010-bootstrap_admin_node.sh.patch
+++ b/build/patch-repos/0010-bootstrap_admin_node.sh.patch
@@ -24,5 +24,18 @@
  nodes over PXE, they will be discovered and become available for installing \
  OpenStack on them"
+@@ -239,6 +239,12 @@
+ # /etc/fuel_openstack_version is provided by 'fuel-openstack-metadata' package
+ OPENSTACK_VERSION=$(cat /etc/fuel_openstack_version)
+
++# FIXME(armband): This part might be moved to an earlier stage later
++# /etc/fuel_openstack_arch is constructed based on local mirror metadata
++grep -oP "^Architectures: \K.*$" \
++    ${wwwdir}/${OPENSTACK_VERSION}/ubuntu/x86_64/dists/mos${FUEL_RELEASE}/Release > \
++    /etc/fuel_openstack_arch
++
+ # We do not ship debian-installer kernel and initrd on ISO.
+ # But we still need to be able to create ubuntu cobbler distro
+ # which requires kernel and initrd to be available. So, we
 @@ -339,8 +339,22 @@ fuelmenu --save-only --iface=$ADMIN_INTERFACE || fail
  set +x
  echo "Done!"
diff --git a/build/f_isoroot/f_bootstrap/post-scripts/80_prepare_cross_builds.sh b/build/f_isoroot/f_bootstrap/post-scripts/80_prepare_cross_builds.sh
new file mode 100755
index 0000000..d33d1d1
--- /dev/null
+++ b/build/f_isoroot/f_bootstrap/post-scripts/80_prepare_cross_builds.sh
@@ -0,0 +1,32 @@
+#/bin/sh
+##############################################################################
+# Copyright (c) 2016 Enea AB and others.
+# Alexandru.Avadanii@enea.com
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Apache License, Version 2.0
+# which accompanies this distribution, and is available at
+# http://www.apache.org/licenses/LICENSE-2.0
+##############################################################################
+
+echo "Preparing for cross-building bootstrap/target images"
+
+# Fmt handlers are set up by qemu-user-static (after systemd-binfmt
+# prerequisites are checked during first boot of Fuel Master node).
+
+# Cross-building support provides dpkg, as a fuel-agent dependency
+if which dpkg > /dev/null 2>&1; then
+  # /etc/fuel_openstack_arch is created by bootstrap_admin_node.sh
+  FOREIGN_ARCH_CNT=$(sed -e "s/$(dpkg --print-architecture)//" \
+    /etc/fuel_openstack_arch | wc -w)
+  if [ ${FOREIGN_ARCH_CNT} -gt 0 ]; then
+    # If no fmt handlers are configured, the service is not started,
+    # so request it explicitly (only necessary for the first boot).
+    systemctl start systemd-binfmt
+    if [ $? -ne 0 ]; then
+      echo "Error starting systemd-binfmt!"
+      exit 1
+    fi
+  fi
+fi
+
+echo "Done preparing cross-building"