Prevent empty 'ServerName', fixes #870

Thanks to h4cc

actions/admin/settings/120.system.php

@@ -59,6 +59,7 @@ return array(
 					'type' => 'string',
 					'default' => '',
 					'save_method' => 'storeSettingHostname',
+					'plausibility_check_method' => 'checkHostname',
 					),
 				'system_froxlordirectlyviahostname' => array(
 					'label' => $lng['serversettings']['froxlordirectlyviahostname'],

lib/functions/validate/function.checkHostname.php

@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * This file is part of the Froxlor project.
+ * Copyright (c) 2010 the Froxlor Team (see authors).
+ *
+ * For the full copyright and license information, please view the COPYING
+ * file that was distributed with this source code. You can also view the
+ * COPYING file online at http://files.froxlor.org/misc/COPYING.txt
+ *
+ * @copyright  (c) the authors
+ * @author     Froxlor team <team@froxlor.org> (2010-)
+ * @license    GPLv2 http://files.froxlor.org/misc/COPYING.txt
+ * @package    Functions
+ *
+ */
+
+function checkHostname($fieldname, $fielddata, $newfieldvalue, $allnewfieldvalues)
+{
+	echo $fieldname . "--" . $fielddata . "--" . $newfieldvalue . "--". $allnewfieldvalues;
+	if (0 == strlen(trim($fielddata)))
+	{
+		return array(FORMFIELDS_PLAUSIBILITY_CHECK_ERROR, 'invalidhostname');
+	} else {
+		return array(FORMFIELDS_PLAUSIBILITY_CHECK_OK);
+	}
+}

lng/english.lng.php

@@ -1898,3 +1898,5 @@ $lng['admin']['assignedmax'] = 'Assigned / Max';
 $lng['admin']['usedmax'] = 'Used / Max';
 $lng['admin']['used'] = 'Used';
 $lng['mysql']['size'] = 'Database size (MB)';
+
+$lng['error']['invalidhostname'] = 'Hostname can\'t be empty nor can it consist only of whitespaces';

lng/german.lng.php

@@ -1629,3 +1629,5 @@ $lng['admin']['assignedmax'] = 'Zugewiesen / Max.';
 $lng['admin']['usedmax'] = 'Benutzt / Max.';
 $lng['admin']['used'] = 'Benutzt';
 $lng['mysql']['size'] = 'Datenbankgröße (MB)';
+
+$lng['error']['invalidhostname'] = 'Hostname darf nicht leer sein oder nur aus Leerzeichen bestehen';