From bbdb92debd3d239b9c76b5c2fb6a1f7200085845 Mon Sep 17 00:00:00 2001
From: Jamie Cameron <jcameron@webmin.com>
Date: Sat, 8 Sep 2018 23:32:18 -0700
Subject: [PATCH] Attempt to preserve unknown config entries

---
 net/netplan-lib.pl | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/net/netplan-lib.pl b/net/netplan-lib.pl
index 73b8dcd3f..ec174dc98 100644
--- a/net/netplan-lib.pl
+++ b/net/netplan-lib.pl
@@ -25,6 +25,7 @@ foreach my $f (glob("$netplan_dir/*.yaml")) {
 		my $cfg = { 'name' => $e->{'name'},
 			    'fullname' => $e->{'name'},
 			    'file' => $f,
+			    'yaml' => $e,
 			    'line' => $e->{'line'},
 			    'eline' => $e->{'eline'},
 			    'edit' => 1,
@@ -211,6 +212,16 @@ else {
 		push(@lines, $id."    "."macaddress: ".$iface->{'ether'});
 		}
 
+	# Add all extra YAML directives from the original config
+	my @poss = ( "optional", "dhcp4", "dhcp6", "addresses", "gateway4",
+		     "gateway6", "nameservers", "macaddress" );
+	if ($iface->{'yaml'}) {
+		foreach my $y (@{$yaml->{'members'}}) {
+			next if (&indexof($y->{'name'}, @poss) >= 0);
+			push(@lines, &yaml_lines($y, $id."    "));
+			}
+		}
+
 	if ($iface->{'file'}) {
 		# Replacing an existing interface
 		my ($old) = grep { $_->{'fullname'} eq $iface->{'fullname'} } @$boot;
@@ -582,6 +593,23 @@ foreach my $origl (@$lref) {
 return $rv;
 }
 
+# yaml_lines(&directive, indent-string)
+sub yaml_lines
+{
+my ($yaml, $id) = @_;
+my @rv;
+push(@rv, $id.$yaml->{'name'}.":".
+	  (ref($yaml->{'value'}) eq 'ARRAY' ?
+		" [".&join_addr_list(@{$yaml->{'value'}})."]" :
+	   defined($yaml->{'value'}) ? " ".$yaml->{'value'} : ""));
+if ($yaml->{'members'}) {
+	foreach my $m (@{$yaml->{'members'}}) {
+		push(@rv, &yaml_lines($m, $id."    "));
+		}
+	}
+return @rv;
+}
+
 # set_parent_elines(&conf, eline)
 sub set_parent_elines
 {