+<?php
+/***************************************************************
+* Copyright notice
+*
+* (c) 2010 Xavier Perseguers <typo3@perseguers.ch>
+* All rights reserved
+*
+* This script is part of the TYPO3 project. The TYPO3 project is
+* free software; you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation; either version 2 of the License, or
+* (at your option) any later version.
+*
+* The GNU General Public License can be found at
+* http://www.gnu.org/copyleft/gpl.html.
+* A copy is found in the textfile GPL.txt and important notices to the license
+* from the author is found in LICENSE.txt distributed with these scripts.
+*
+*
+* This script is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU General Public License for more details.
+*
+* This copyright notice MUST APPEAR in all copies of the script!
+***************************************************************/
+
+/**
+ * Interface for hook in SC_mod_tools_em_index::checkDBupdates.
+ *
+ * @author Xavier Perseguers <typo3@perseguers.ch>
+ * @package TYPO3
+ * @subpackage em
+ */
+interface em_index_checkDatabaseUpdatesHook {
+
+ /**
+ * Hook that allows pre-processing of database structure modifications.
+ * The hook implementation may return a user form that will temporarily
+ * replace the standard database update form. This allows additional
+ * operations to be performed before the database structure gets updated.
+ *
+ * @param string $extKey: Extension key
+ * @param array $extInfo: Extension information array
+ * @param array $diff: Database differences
+ * @param t3lib_install $instObj: Instance of the installer
+ * @param SC_mod_tools_em_index $parent: The calling parent object
+ * @return string Either empty string or a pre-processing user form
+ */
+ public function preProcessDatabaseUpdates($extKey, array $extInfo, array $diff, t3lib_install $instObj, SC_mod_tools_em_index $parent);
+
+}
+
+?>
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