1 files changed, 55 insertions, 0 deletions
diff --git a/debian/libnss-resolve.postinst b/debian/libnss-resolve.postinst
new file mode 100644
index 0000000..21b19c8
--- /dev/null
+++ b/debian/libnss-resolve.postinst
@@ -0,0 +1,55 @@
+#!/bin/sh
+set -e
+
+# This code was taken from libnss-myhostname
+
+# try to insert resolve entries to the "hosts" line in /etc/nsswitch.conf to
+# automatically enable libnss-resolve support; do not change the
+# configuration if the "hosts" line already references some resolve lookups
+insert_nss_entry() {
+    echo "Checking NSS setup..."
+    # abort if /etc/nsswitch.conf does not exist
+    if ! [ -e /etc/nsswitch.conf ]; then
+        echo "Could not find /etc/nsswitch.conf."
+        return
+    fi
+    perl -i -pe '
+        sub insert {
+            my $line = shift;
+            # this also splits on tab
+            my @bits=split(" ", $line);
+            # do not break configuration if the "hosts" line already references
+            # resolve
+            if (grep { $_ eq "resolve"} @bits) {
+                return $line;
+            }
+            # add resolve before dns
+            return join " ", map {
+                $_ eq "dns" ? ("resolve [!UNAVAIL=return]", "$_") : $_
+            } @bits;
+        }
+        s/^(hosts:\s+)(.*)/$1.insert($2)/e;
+    ' /etc/nsswitch.conf
+}
+
+if [ "$1" = configure ] && [ -z "$2" ]; then
+    echo "First installation detected..."
+    # first install: setup the recommended configuration (unless
+    # nsswitch.conf already contains resolve entries)
+    insert_nss_entry
+    # ... and enable resolved
+    systemctl enable systemd-resolved.service
+    if [ -d /run/systemd/system ]; then
+        deb-systemd-invoke start systemd-resolved.service || true
+    fi
+fi
+
+# Fix nsswitch action on upgrades
+if [ "$1" = configure ] && dpkg --compare-versions "$2" lt-nl "231-10"; then
+    if ! grep -q '^hosts:.*resolve[[:space:]]*\[' /etc/nsswitch.conf; then
+        echo "Adjusting 'resolv' entry in /etc/nsswitch.conf.."
+        sed -i '/^hosts:/ { s/resolve/& [!UNAVAIL=return]/}' /etc/nsswitch.conf
+    fi
+fi
+
+#DEBHELPER#