fix: Fix minor perl errors on linux when no domain has been setup

Author: g-bougard

lib/GLPI/Agent/Task/Inventory/Generic/Domains.pm

@@ -47,7 +47,7 @@ sub doInventory {
     # attempt to deduce the actual domain from the host name
     # and fallback on the domain search list
     my $hostname = getHostname(fqdn => 1);
-    my $pos = index $hostname, '.';
+    my $pos = empty($hostname) ? 0 : index $hostname, '.';
 
     if ($pos > 0) {
         $hostname =~ s/\.+$//;

lib/GLPI/Agent/Tools/Hostname.pm

@@ -60,8 +60,11 @@ sub _getHostnameUnix {
 
     if ($params{fqdn}) {
         Net::Domain->require();
-        $hostname = Net::Domain::hostfqdn();
-        $hostname =~ s/\.$//;  # the module may return a trailing dot
+        my $fqdn = Net::Domain::hostfqdn();
+        unless (empty($fqdn)) {
+            $fqdn =~ s/\.$//;  # the module may return a trailing dot
+            $hostname = $fqdn;
+        }
     } else {
         Sys::Hostname->require();
         $hostname = Sys::Hostname::hostname();