Index: branches/5.2.x/core/install/prerequisites.php
===================================================================
diff -u -N -r14699 -r14860
--- branches/5.2.x/core/install/prerequisites.php	(.../prerequisites.php)	(revision 14699)
+++ branches/5.2.x/core/install/prerequisites.php	(.../prerequisites.php)	(revision 14860)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: prerequisites.php 14699 2011-10-26 11:39:38Z alex $
+* @version	$Id: prerequisites.php 14860 2011-12-12 11:36:50Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -20,7 +20,7 @@
 	 * Class, that holds all prerequisite scripts for "In-Portal" module
 	 *
 	 */
-	class InPortalPrerequisites extends kHelper {
+	class InPortalPrerequisites {
 
 		/**
 		 * Install toolkit instance
@@ -30,6 +30,14 @@
 		var $_toolkit = null;
 
 		/**
+		* Connection to database
+		*
+		* @var kDBConnection
+		* @access protected
+		*/
+		protected $Conn = null;
+
+		/**
 		 * Sets common instance of installator toolkit
 		 *
 		 * @param kInstallToolkit $instance
@@ -42,6 +50,16 @@
 		/**
 		 * Checks minimal version, that could be upgradeable
 		 *
+		 * @return kDBConnection
+		 */
+		function &getConnection()
+		{
+			return $this->_toolkit->Conn;
+		}
+
+		/**
+		 * Checks minimal version, that could be upgradeable
+		 *
 		 * @param Array $versions
 		 * @param string $mode when called mode {install, upgrade, standalone)
 		 * @return Array
@@ -54,8 +72,10 @@
 				$sql = 'SELECT Version
 						FROM ' . TABLE_PREFIX . 'Modules
 						WHERE Name = "In-Portal"';
-				$inportal_version = $this->Conn->GetOne($sql);
 
+				$conn =& $this->getConnection();
+				$inportal_version = $conn->GetOne($sql);
+
 				if ($inportal_version === false) {
 					// only, when In-Portal was installed
 					return $errors;
@@ -72,4 +92,87 @@
 
 			return $errors;
 		}
+
+		/**
+		 * Returns information about system requirements
+		 *
+		 * @return array
+		 */
+		function CheckSystemRequirements()
+		{
+			$ret = Array ();
+			$ret['php_version'] = version_compare(PHP_VERSION, '5.2.0', '>=');
+
+			$ret['url_rewriting'] = function_exists('apache_get_modules') && in_array('mod_rewrite', apache_get_modules());
+			$ret['memcache'] = class_exists('Memcache');
+			$ret['curl'] = function_exists('curl_init');
+			$ret['freetype'] = function_exists('imagettfbbox');
+
+			$ret['gd_version'] = $ret['jpeg'] = false;
+
+			if ( function_exists('gd_info') ) {
+				$gd_info = gd_info();
+
+				$gd_version = preg_replace('/[^\d.]/', '', $gd_info['GD Version']);
+				$ret['gd_version'] = version_compare($gd_version, '1.8', '>=');
+
+				$ret['jpeg'] = isset($gd_info['JPEG Support']) && $gd_info['JPEG Support'];
+			}
+
+			$ret['mysql'] = function_exists('mysql_connect');
+			$ret['json'] = function_exists('json_encode');
+
+			$ret['memory_limit'] = $this->isPhpSettingChangeable('memory_limit', '33M');
+			$ret['date.timezone'] = ini_get('date.timezone') != '';
+
+			$ret['variables_order'] = strpos(ini_get('variables_order'), 'GPC') !== false;
+			$ret['output_buffering'] = ini_get('output_buffering') > 0;
+
+			return $ret;
+		}
+
+		/**
+		 * Detects if setting of php.ini can be changed
+		 *
+		 * @param string $setting_name
+		 * @param string $new_value
+		 * @return bool
+		 */
+		protected function isPhpSettingChangeable($setting_name, $new_value)
+		{
+			$backup_value = ini_get($setting_name);
+			ini_set($setting_name, $new_value);
+
+			if ( ini_get($setting_name) != $backup_value ) {
+				ini_set($setting_name, $backup_value);
+
+				return true;
+			}
+
+			return false;
+		}
+
+		/**
+		 * Returns information about DB requirements
+		 *
+		 * @return array
+		 */
+		function CheckDBRequirements()
+		{
+			// check PHP version 5.2+
+			$ret = Array();
+
+			$sql = 'SELECT VERSION()';
+			$conn =& $this->getConnection();
+
+			$db_version = preg_replace('/[^\d.]/', '', $conn->GetOne($sql));
+			$ret['version'] = version_compare($db_version, '5.0', '>=');
+
+			$sql = 'SHOW VARIABLES LIKE "max_allowed_packet"';
+			$db_variables = $conn->Query($sql, 'Variable_name');
+
+			$ret['packet_size'] = $db_variables['max_allowed_packet']['Value'] >= 1048576;
+
+			return $ret;
+		}
 	}
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