Checks if config folder is writable on begin of the installation.

lib/util.php

@@ -20,10 +20,18 @@ class OC_Util {
 		$CONFIG_DATADIRECTORY_ROOT = OC_Config::getValue( "datadirectory", OC::$SERVERROOT."/data" );
 		$CONFIG_BACKUPDIRECTORY = OC_Config::getValue( "backupdirectory", OC::$SERVERROOT."/backup" );
 
-		// Create root dir
+		// Check if config folder is writable.
+		if(!is_writable(OC::$SERVERROOT."/config/")) {
+			$tmpl = new OC_Template( '', 'error', 'guest' );
+			$tmpl->assign('errors',array(1=>array('error'=>"Can't write into config directory 'config'",'hint'=>"You can usually fix this by giving the webserver user write access to the config directory in owncloud")));
+			$tmpl->printPage();
+			exit;
+		}
+		
+		// Create root dir.
 		if(!is_dir($CONFIG_DATADIRECTORY_ROOT)){
 			$success=@mkdir($CONFIG_DATADIRECTORY_ROOT);
-                        if(!$success) {
+            if(!$success) {
 				$tmpl = new OC_Template( '', 'error', 'guest' );
 				$tmpl->assign('errors',array(1=>array('error'=>"Can't create data directory (".$CONFIG_DATADIRECTORY_ROOT.")",'hint'=>"You can usually fix this by giving the webserver write access to the ownCloud directory '".OC::$SERVERROOT."' (in a terminal, use the command 'chown -R www-data:www-data /path/to/your/owncloud/install/data' ")));
 				$tmpl->printPage();