Merge branch 'develop' into feature/user-guide-cleanup

15 files changed, 988 insertions, 816 deletions

diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index c68266408..74a9eb0af 100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -48,24 +48,22 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 
 /*
  * ------------------------------------------------------
- *  Load the global functions
+ *  Load the framework constants
  * ------------------------------------------------------
  */
-	require_once(BASEPATH.'core/Common.php');
+	if (file_exists(APPPATH.'config/'.ENVIRONMENT.'/constants.php'))
+	{
+		require_once(APPPATH.'config/'.ENVIRONMENT.'/constants.php');
+	}
+
+	require_once(APPPATH.'config/constants.php');
 
 /*
  * ------------------------------------------------------
- *  Load the framework constants
+ *  Load the global functions
  * ------------------------------------------------------
  */
-	if (file_exists(APPPATH.'config/'.ENVIRONMENT.'/constants.php'))
-	{
-		require(APPPATH.'config/'.ENVIRONMENT.'/constants.php');
-	}
-	else
-	{
-		require(APPPATH.'config/constants.php');
-	}
+	require_once(BASEPATH.'core/Common.php');
 
 /*
  * ------------------------------------------------------
@@ -73,11 +71,10 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  * ------------------------------------------------------
  */
 	set_error_handler('_exception_handler');
+	register_shutdown_function('_shutdown_handler');
 
-	if ( ! is_php('5.4'))
-	{
-		@ini_set('magic_quotes_runtime', 0); // Kill magic quotes
-	}
+	// Kill magic quotes
+	is_php('5.4') OR @ini_set('magic_quotes_runtime', 0);
 
 /*
  * ------------------------------------------------------
@@ -88,7 +85,7 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  * The subclass prefix allows CI to know if a core class is
  * being extended via a library in the local application
  * "libraries" folder. Since CI allows config items to be
- * overriden via data set in the main index. php file,
+ * overriden via data set in the main index.php file,
  * before proceeding we need to know if a subclass_prefix
  * override exists. If so, we will set this value now,
  * before any classes are loaded
@@ -166,12 +163,6 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  */
 	$RTR =& load_class('Router', 'core');
 
-	// Set any routing overrides that may exist in the main index file
-	if (isset($routing))
-	{
-		$RTR->_set_overrides($routing);
-	}
-
 /*
  * ------------------------------------------------------
  *  Instantiate the output class
@@ -218,7 +209,7 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  *
  */
 	// Load the base controller class
-	require BASEPATH.'core/Controller.php';
+	require_once BASEPATH.'core/Controller.php';
 
 	/**
 	 * Reference to the CI_Controller method.
@@ -234,92 +225,117 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 
 	if (file_exists(APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php'))
 	{
-		require APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php';
+		require_once APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php';
 	}
 
-	// Load the local application controller
-	// Note: The Router class automatically validates the controller path using the router->_validate_request().
-	// If this include fails it means that the default controller in the Routes.php file is not resolving to something valid.
-	if ( ! file_exists(APPPATH.'controllers/'.$RTR->directory.$RTR->class.'.php'))
-	{
-		show_error('Unable to load your default controller. Please make sure the controller specified in your Routes.php file is valid.');
-	}
-
-	include(APPPATH.'controllers/'.$RTR->directory.$RTR->class.'.php');
-
 	// Set a mark point for benchmarking
 	$BM->mark('loading_time:_base_classes_end');
 
 /*
  * ------------------------------------------------------
- *  Security check
+ *  Sanity checks
  * ------------------------------------------------------
  *
- *  None of the methods in the app controller or the
- *  loader class can be called via the URI, nor can
- *  controller functions that begin with an underscore.
+ *  The Router class has already validated the request,
+ *  leaving us with 3 options here:
+ *
+ *	1) an empty class name, if we reached the default
+ *	   controller, but it didn't exist;
+ *	2) a query string which doesn't go through a
+ *	   file_exists() check
+ *	3) a regular request for a non-existing page
+ *
+ *  We handle all of these as a 404 error.
+ *
+ *  Furthermore, none of the methods in the app controller
+ *  or the loader class can be called via the URI, nor can
+ *  controller methods that begin with an underscore.
  */
-	$class	= $RTR->class;
-	$method	= $RTR->method;
-
-	if ( ! class_exists($class, FALSE) OR $method[0] === '_' OR method_exists('CI_Controller', $method))
-	{
-		if ( ! empty($RTR->routes['404_override']))
-		{
-			if (sscanf($RTR->routes['404_override'], '%[^/]/%s', $class, $method) !== 2)
-			{
-				$method = 'index';
-			}
-
-			if ( ! class_exists($class, FALSE))
-			{
-				if ( ! file_exists(APPPATH.'controllers/'.$class.'.php'))
-				{
-					show_404($class.'/'.$method);
-				}
 
-				include_once(APPPATH.'controllers/'.$class.'.php');
-			}
-		}
-		else
-		{
-			show_404($class.'/'.$method);
-		}
-	}
+	$e404 = FALSE;
+	$class = ucfirst($RTR->class);
+	$method = $RTR->method;
 
-	if (method_exists($class, '_remap'))
+	if (empty($class) OR ! file_exists(APPPATH.'controllers/'.$RTR->directory.$class.'.php'))
 	{
-		$params = array($method, array_slice($URI->rsegments, 2));
-		$method = '_remap';
+		$e404 = TRUE;
 	}
 	else
 	{
+		require_once(APPPATH.'controllers/'.$RTR->directory.$class.'.php');
+
+		if ( ! class_exists($class, FALSE) OR $method[0] === '_' OR method_exists('CI_Controller', $method))
+		{
+			$e404 = TRUE;
+		}
+		elseif (method_exists($class, '_remap'))
+		{
+			$params = array($method, array_slice($URI->rsegments, 2));
+			$method = '_remap';
+		}
 		// WARNING: It appears that there are issues with is_callable() even in PHP 5.2!
 		// Furthermore, there are bug reports and feature/change requests related to it
 		// that make it unreliable to use in this context. Please, DO NOT change this
 		// work-around until a better alternative is available.
-		if ( ! in_array(strtolower($method), array_map('strtolower', get_class_methods($class)), TRUE))
+		elseif ( ! in_array(strtolower($method), array_map('strtolower', get_class_methods($class)), TRUE))
 		{
-			if (empty($RTR->routes['404_override']))
-			{
-				show_404($class.'/'.$method);
-			}
-			elseif (sscanf($RTR->routes['404_override'], '%[^/]/%s', $class, $method) !== 2)
+			$e404 = TRUE;
+		}
+	}
+
+	if ($e404)
+	{
+		if ( ! empty($RTR->routes['404_override']))
+		{
+			if (sscanf($RTR->routes['404_override'], '%[^/]/%s', $error_class, $error_method) !== 2)
 			{
-				$method = 'index';
+				$error_method = 'index';
 			}
 
-			if ( ! class_exists($class, FALSE))
+			$error_class = ucfirst($error_class);
+
+			if ( ! class_exists($error_class, FALSE))
 			{
-				if ( ! file_exists(APPPATH.'controllers/'.$class.'.php'))
+				if (file_exists(APPPATH.'controllers/'.$RTR->directory.$error_class.'.php'))
 				{
-					show_404($class.'/'.$method);
+					require_once(APPPATH.'controllers/'.$RTR->directory.$error_class.'.php');
+					$e404 = ! class_exists($error_class, FALSE);
 				}
-
-				include_once(APPPATH.'controllers/'.$class.'.php');
+				// Were we in a directory? If so, check for a global override
+				elseif ( ! empty($RTR->directory) && file_exists(APPPATH.'controllers/'.$error_class.'.php'))
+				{
+					require_once(APPPATH.'controllers/'.$error_class.'.php');
+					if (($e404 = ! class_exists($error_class, FALSE)) === FALSE)
+					{
+						$RTR->directory = '';
+					}
+				}
+			}
+			else
+			{
+				$e404 = FALSE;
 			}
 		}
 
+		// Did we reset the $e404 flag? If so, set the rsegments, starting from index 1
+		if ( ! $e404)
+		{
+			$class = $error_class;
+			$method = $error_method;
+
+			$URI->rsegments = array(
+				1 => $class,
+				2 => $method
+			);
+		}
+		else
+		{
+			show_404($RTR->directory.$class.'/'.$method);
+		}
+	}
+
+	if ($method !== '_remap')
+	{
 		$params = array_slice($URI->rsegments, 2);
 	}
 
diff --git a/system/core/Common.php b/system/core/Common.php
index b95a05db9..00e303098 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -82,7 +82,7 @@ if ( ! function_exists('is_really_writable'))
 	function is_really_writable($file)
 	{
 		// If we're on a Unix server with safe_mode off we call is_writable
-		if (DIRECTORY_SEPARATOR === '/' && (bool) @ini_get('safe_mode') === FALSE)
+		if (DIRECTORY_SEPARATOR === '/' && (is_php('5.4') OR (bool) @ini_get('safe_mode') === FALSE))
 		{
 			return is_writable($file);
 		}
@@ -224,56 +224,51 @@ if ( ! function_exists('get_config'))
 	 * @param	array
 	 * @return	array
 	 */
-	function &get_config($replace = array())
+	function &get_config(Array $replace = array())
 	{
 		static $_config;
 
-		if (isset($_config))
+		if (empty($_config))
 		{
-			return $_config[0];
-		}
+			$file_path = APPPATH.'config/config.php';
+			$found = FALSE;
+			if (file_exists($file_path))
+			{
+				$found = TRUE;
+				require($file_path);
+			}
 
-		$file_path = APPPATH.'config/config.php';
-		$found = FALSE;
-		if (file_exists($file_path))
-		{
-			$found = TRUE;
-			require($file_path);
-		}
+			// Is the config file in the environment folder?
+			if (file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/config.php'))
+			{
+				require($file_path);
+			}
+			elseif ( ! $found)
+			{
+				set_status_header(503);
+				echo 'The configuration file does not exist.';
+				exit(EXIT_CONFIG);
+			}
 
-		// Is the config file in the environment folder?
-		if (file_exists($file_path = APPPATH.'config/'.ENVIRONMENT.'/config.php'))
-		{
-			require($file_path);
-		}
-		elseif ( ! $found)
-		{
-			set_status_header(503);
-			echo 'The configuration file does not exist.';
-			exit(EXIT_CONFIG);
-		}
+			// Does the $config array exist in the file?
+			if ( ! isset($config) OR ! is_array($config))
+			{
+				set_status_header(503);
+				echo 'Your config file does not appear to be formatted correctly.';
+				exit(EXIT_CONFIG);
+			}
 
-		// Does the $config array exist in the file?
-		if ( ! isset($config) OR ! is_array($config))
-		{
-			set_status_header(503);
-			echo 'Your config file does not appear to be formatted correctly.';
-			exit(EXIT_CONFIG);
+			// references cannot be directly assigned to static variables, so we use an array
+			$_config[0] =& $config;
 		}
 
-		// Are any values being dynamically replaced?
-		if (count($replace) > 0)
+		// Are any values being dynamically added or replaced?
+		foreach ($replace as $key => $val)
 		{
-			foreach ($replace as $key => $val)
-			{
-				if (isset($config[$key]))
-				{
-					$config[$key] = $val;
-				}
-			}
+			$_config[0][$key] = $val;
 		}
 
-		return $_config[0] =& $config;
+		return $_config[0];
 	}
 }
 
@@ -360,6 +355,24 @@ if ( ! function_exists('is_https'))
 
 // ------------------------------------------------------------------------
 
+if ( ! function_exists('is_cli'))
+{
+
+	/**
+	 * Is CLI?
+	 *
+	 * Test to see if a request was made from the command line.
+	 *
+	 * @return 	bool
+	 */
+	function is_cli()
+	{
+		return (PHP_SAPI === 'cli' OR defined('STDIN'));
+	}
+}
+
+// ------------------------------------------------------------------------
+
 if ( ! function_exists('show_error'))
 {
 	/**
@@ -434,29 +447,19 @@ if ( ! function_exists('log_message'))
 	 *
 	 * @param	string	the error level: 'error', 'debug' or 'info'
 	 * @param	string	the error message
-	 * @param	bool	whether the error is a native PHP error
 	 * @return	void
 	 */
-	function log_message($level, $message, $php_error = FALSE)
+	function log_message($level, $message)
 	{
-		static $_log, $_log_threshold;
-
-		if ($_log_threshold === NULL)
-		{
-			$_log_threshold = config_item('log_threshold');
-		}
-
-		if ($_log_threshold === 0)
-		{
-			return;
-		}
+		static $_log;
 
 		if ($_log === NULL)
 		{
-			$_log =& load_class('Log', 'core');
+			// references cannot be directly assigned to static variables, so we use an array
+			$_log[0] =& load_class('Log', 'core');
 		}
 
-		$_log->write_log($level, $message, $php_error);
+		$_log[0]->write_log($level, $message);
 	}
 }
 
@@ -538,7 +541,7 @@ if ( ! function_exists('set_status_header'))
 
 		$server_protocol = isset($_SERVER['SERVER_PROTOCOL']) ? $_SERVER['SERVER_PROTOCOL'] : FALSE;
 
-		if (strpos(php_sapi_name(), 'cgi') === 0)
+		if (strpos(PHP_SAPI, 'cgi') === 0)
 		{
 			header('Status: '.$code.' '.$text, TRUE);
 		}
@@ -556,22 +559,35 @@ if ( ! function_exists('_exception_handler'))
 	/**
 	 * Exception Handler
 	 *
-	 * This is the custom exception handler that is declaired at the top
-	 * of Codeigniter.php. The main reason we use this is to permit
+	 * This is the custom exception handler that is declared at the top
+	 * of CodeIgniter.php. The main reason we use this is to permit
 	 * PHP errors to be logged in our own log files since the user may
 	 * not have access to server logs. Since this function
 	 * effectively intercepts PHP errors, however, we also need
 	 * to display errors based on the current error_reporting level.
 	 * We do that with the use of a PHP error template.
 	 *
-	 * @param	int
-	 * @param	string
-	 * @param	string
-	 * @param	int
+	 * @param	int	$severity
+	 * @param	string	$message
+	 * @param	string	$filepath
+	 * @param	int	$line
 	 * @return	void
 	 */
 	function _exception_handler($severity, $message, $filepath, $line)
 	{
+		$is_error = (((E_ERROR | E_COMPILE_ERROR | E_CORE_ERROR | E_USER_ERROR) & $severity) === $severity);
+
+		// When an error occurred, set the status header to '500 Internal Server Error'
+		// to indicate to the client something went wrong.
+		// This can't be done within the $_error->show_php_error method because
+		// it is only called when the display_errors flag is set (which isn't usually
+		// the case in a production environment) or when errors are ignored because
+		// they are above the error_reporting threshold.
+		if ($is_error)
+		{
+			set_status_header(500);
+		}
+
 		$_error =& load_class('Exceptions', 'core');
 
 		// Should we ignore the error? We'll get the current error_reporting
@@ -588,6 +604,42 @@ if ( ! function_exists('_exception_handler'))
 		}
 
 		$_error->log_exception($severity, $message, $filepath, $line);
+
+		// If the error is fatal, the execution of the script should be stopped because
+		// errors can't be recovered from. Halting the script conforms with PHP's
+		// default error handling. See http://www.php.net/manual/en/errorfunc.constants.php
+		if ($is_error)
+		{
+			exit(EXIT_ERROR);
+		}
+	}
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('_shutdown_handler'))
+{
+	/**
+	 * Shutdown Handler
+	 *
+	 * This is the shutdown handler that is declared at the top
+	 * of CodeIgniter.php. The main reason we use this is to simulate
+	 * a complete custom exception handler.
+	 *
+	 * E_STRICT is purposivly neglected because such events may have
+	 * been caught. Duplication or none? None is preferred for now.
+	 *
+	 * @link	http://insomanic.me.uk/post/229851073/php-trick-catching-fatal-errors-e-error-with-a
+	 * @return	void
+	 */
+	function _shutdown_handler()
+	{
+		$last_error = error_get_last();
+		if (isset($last_error) &&
+			($last_error['type'] & (E_ERROR | E_PARSE | E_CORE_ERROR | E_CORE_WARNING | E_COMPILE_ERROR | E_COMPILE_WARNING)))
+		{
+			_exception_handler($last_error['type'], $last_error['message'], $last_error['file'], $last_error['line']);
+		}
 	}
 }
 
diff --git a/system/core/Config.php b/system/core/Config.php
index 7e64444bc..a0e830abe 100644
--- a/system/core/Config.php
+++ b/system/core/Config.php
@@ -184,16 +184,16 @@ class CI_Config {
 	 *
 	 * @param	string	$item	Config item name
 	 * @param	string	$index	Index name
-	 * @return	string|bool	The configuration item or FALSE on failure
+	 * @return	string|null	The configuration item or NULL if the item doesn't exist
 	 */
 	public function item($item, $index = '')
 	{
 		if ($index == '')
 		{
-			return isset($this->config[$item]) ? $this->config[$item] : FALSE;
+			return isset($this->config[$item]) ? $this->config[$item] : NULL;
 		}
 
-		return isset($this->config[$index], $this->config[$index][$item]) ? $this->config[$index][$item] : FALSE;
+		return isset($this->config[$index], $this->config[$index][$item]) ? $this->config[$index][$item] : NULL;
 	}
 
 	// --------------------------------------------------------------------
@@ -202,13 +202,13 @@ class CI_Config {
 	 * Fetch a config file item with slash appended (if not empty)
 	 *
 	 * @param	string		$item	Config item name
-	 * @return	string|bool	The configuration item or FALSE on failure
+	 * @return	string|null	The configuration item or NULL if the item doesn't exist
 	 */
 	public function slash_item($item)
 	{
 		if ( ! isset($this->config[$item]))
 		{
-			return FALSE;
+			return NULL;
 		}
 		elseif (trim($this->config[$item]) === '')
 		{
@@ -228,13 +228,21 @@ class CI_Config {
 	 * @uses	CI_Config::_uri_string()
 	 *
 	 * @param	string|string[]	$uri	URI string or an array of segments
+	 * @param	string	$protocol
 	 * @return	string
 	 */
-	public function site_url($uri = '')
+	public function site_url($uri = '', $protocol = NULL)
 	{
+		$base_url = $this->slash_item('base_url');
+
+		if (isset($protocol))
+		{
+			$base_url = $protocol.substr($base_url, strpos($base_url, '://'));
+		}
+
 		if (empty($uri))
 		{
-			return $this->slash_item('base_url').$this->item('index_page');
+			return $base_url.$this->item('index_page');
 		}
 
 		$uri = $this->_uri_string($uri);
@@ -255,14 +263,14 @@ class CI_Config {
 				}
 			}
 
-			return $this->slash_item('base_url').$this->slash_item('index_page').$uri;
+			return $base_url.$this->slash_item('index_page').$uri;
 		}
 		elseif (strpos($uri, '?') === FALSE)
 		{
 			$uri = '?'.$uri;
 		}
 
-		return $this->slash_item('base_url').$this->item('index_page').$uri;
+		return $base_url.$this->item('index_page').$uri;
 	}
 
 	// -------------------------------------------------------------
@@ -275,11 +283,19 @@ class CI_Config {
 	 * @uses	CI_Config::_uri_string()
 	 *
 	 * @param	string|string[]	$uri	URI string or an array of segments
+	 * @param	string	$protocol
 	 * @return	string
 	 */
-	public function base_url($uri = '')
+	public function base_url($uri = '', $protocol = NULL)
 	{
-		return $this->slash_item('base_url').ltrim($this->_uri_string($uri), '/');
+		$base_url = $this->slash_item('base_url');
+
+		if (isset($protocol))
+		{
+			$base_url = $protocol.substr($base_url, strpos($base_url, '://'));
+		}
+
+		return $base_url.ltrim($this->_uri_string($uri), '/');
 	}
 
 	// -------------------------------------------------------------
diff --git a/system/core/Exceptions.php b/system/core/Exceptions.php
index 9c68d06a5..809dc027a 100644
--- a/system/core/Exceptions.php
+++ b/system/core/Exceptions.php
@@ -91,7 +91,7 @@ class CI_Exceptions {
 	public function log_exception($severity, $message, $filepath, $line)
 	{
 		$severity = isset($this->levels[$severity]) ? $this->levels[$severity] : $severity;
-		log_message('error', 'Severity: '.$severity.'  --> '.$message. ' '.$filepath.' '.$line, TRUE);
+		log_message('error', 'Severity: '.$severity.' --> '.$message.' '.$filepath.' '.$line);
 	}
 
 	// --------------------------------------------------------------------
@@ -107,13 +107,21 @@ class CI_Exceptions {
 	 */
 	public function show_404($page = '', $log_error = TRUE)
 	{
-		$heading = '404 Page Not Found';
-		$message = 'The page you requested was not found.';
+		if (is_cli())
+		{
+			$heading = 'Not Found';
+			$message = 'The controller/method pair you requested was not found.';
+		}
+		else
+		{
+			$heading = '404 Page Not Found';
+			$message = 'The page you requested was not found.';
+		}
 
 		// By default we log this, but allow a dev to skip it
 		if ($log_error)
 		{
-			log_message('error', '404 Page Not Found --> '.$page);
+			log_message('error', $heading.': '.$page);
 		}
 
 		echo $this->show_error($heading, $message, 'error_404', 404);
@@ -137,16 +145,24 @@ class CI_Exceptions {
 	 */
 	public function show_error($heading, $message, $template = 'error_general', $status_code = 500)
 	{
-		set_status_header($status_code);
-
-		$message = '<p>'.implode('</p><p>', is_array($message) ? $message : array($message)).'</p>';
+		if (is_cli())
+		{
+			$message = "\t".(is_array($message) ? implode("\n\t", $message) : $message);
+			$template = 'cli'.DIRECTORY_SEPARATOR.$template;
+		}
+		else
+		{
+			set_status_header($status_code);
+			$message = '<p>'.(is_array($message) ? implode('</p><p>', $message) : $message).'</p>';
+			$template = 'html'.DIRECTORY_SEPARATOR.$template;
+		}
 
 		if (ob_get_level() > $this->ob_level + 1)
 		{
 			ob_end_flush();
 		}
 		ob_start();
-		include(VIEWPATH.'errors/'.$template.'.php');
+		include(VIEWPATH.'errors'.DIRECTORY_SEPARATOR.$template.'.php');
 		$buffer = ob_get_contents();
 		ob_end_clean();
 		return $buffer;
@@ -166,13 +182,22 @@ class CI_Exceptions {
 	public function show_php_error($severity, $message, $filepath, $line)
 	{
 		$severity = isset($this->levels[$severity]) ? $this->levels[$severity] : $severity;
-		$filepath = str_replace('\\', '/', $filepath);
 
-		// For safety reasons we do not show the full file path
-		if (FALSE !== strpos($filepath, '/'))
+		// For safety reasons we don't show the full file path in non-CLI requests
+		if ( ! is_cli())
+		{
+			$filepath = str_replace('\\', '/', $filepath);
+			if (FALSE !== strpos($filepath, '/'))
+			{
+				$x = explode('/', $filepath);
+				$filepath = $x[count($x)-2].'/'.end($x);
+			}
+
+			$template = 'html'.DIRECTORY_SEPARATOR.'error_php';
+		}
+		else
 		{
-			$x = explode('/', $filepath);
-			$filepath = $x[count($x)-2].'/'.end($x);
+			$template = 'cli'.DIRECTORY_SEPARATOR.'error_php';
 		}
 
 		if (ob_get_level() > $this->ob_level + 1)
@@ -180,7 +205,7 @@ class CI_Exceptions {
 			ob_end_flush();
 		}
 		ob_start();
-		include(VIEWPATH.'errors/error_php.php');
+		include(VIEWPATH.'errors'.DIRECTORY_SEPARATOR.$template.'.php');
 		$buffer = ob_get_contents();
 		ob_end_clean();
 		echo $buffer;
diff --git a/system/core/Hooks.php b/system/core/Hooks.php
index b3b111991..9bcc23a65 100644
--- a/system/core/Hooks.php
+++ b/system/core/Hooks.php
@@ -54,6 +54,13 @@ class CI_Hooks {
 	public $hooks =	array();
 
 	/**
+	 * Array with class objects to use hooks methods
+	 *
+	 * @var array
+	 */
+	protected $_objects = array();
+
+	/**
 	 * In progress flag
 	 *
 	 * Determines whether hook is in progress, used to prevent infinte loops
@@ -184,7 +191,7 @@ class CI_Hooks {
 		$function	= empty($data['function']) ? FALSE : $data['function'];
 		$params		= isset($data['params']) ? $data['params'] : '';
 
-		if ($class === FALSE && $function === FALSE)
+		if (empty($function))
 		{
 			return FALSE;
 		}
@@ -195,19 +202,39 @@ class CI_Hooks {
 		// Call the requested class and/or function
 		if ($class !== FALSE)
 		{
-			if ( ! class_exists($class, FALSE))
+			// The object is stored?
+			if (isset($this->_objects[$class]))
 			{
-				require($filepath);
+				if (method_exists($this->_objects[$class], $function))
+				{
+					$this->_objects[$class]->$function($params);
+				}
+				else
+				{
+					return $this->_in_progress = FALSE;
+				}
 			}
+			else
+			{
+				class_exists($class, FALSE) OR require_once($filepath);
+
+				if ( ! class_exists($class, FALSE) OR ! method_exists($class, $function))
+				{
+					return $this->_in_progress = FALSE;
+				}
 
-			$HOOK = new $class();
-			$HOOK->$function($params);
+				// Store the object and execute the method
+				$this->_objects[$class] = new $class();
+				$this->_objects[$class]->$function($params);
+			}
 		}
 		else
 		{
+			function_exists($function) OR require_once($filepath);
+
 			if ( ! function_exists($function))
 			{
-				require($filepath);
+				return $this->_in_progress = FALSE;
 			}
 
 			$function($params);
diff --git a/system/core/Input.php b/system/core/Input.php
index 0ef81128e..ccb70daec 100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -47,7 +47,7 @@ class CI_Input {
 	public $ip_address = FALSE;
 
 	/**
-	 * User agent strin
+	 * User agent string
 	 *
 	 * @var	string
 	 */
@@ -63,7 +63,7 @@ class CI_Input {
 	protected $_allow_get_array = TRUE;
 
 	/**
-	 * Standartize new lines flag
+	 * Standardize new lines flag
 	 *
 	 * If set to TRUE, then newlines are standardized.
 	 *
@@ -121,9 +121,10 @@ class CI_Input {
 	{
 		log_message('debug', 'Input Class Initialized');
 
-		$this->_allow_get_array	= (config_item('allow_get_array') === TRUE);
-		$this->_enable_xss	= (config_item('global_xss_filtering') === TRUE);
-		$this->_enable_csrf	= (config_item('csrf_protection') === TRUE);
+		$this->_allow_get_array		= (config_item('allow_get_array') === TRUE);
+		$this->_enable_xss		= (config_item('global_xss_filtering') === TRUE);
+		$this->_enable_csrf		= (config_item('csrf_protection') === TRUE);
+		$this->_sandardize_newlines	= (bool) config_item('standardize_newlines');
 
 		global $SEC;
 		$this->security =& $SEC;
@@ -151,8 +152,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	protected function _fetch_from_array(&$array, $index = '', $xss_clean = FALSE)
+	protected function _fetch_from_array(&$array, $index = '', $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		if (isset($array[$index]))
 		{
 			$value = $array[$index];
@@ -197,8 +200,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function get($index = NULL, $xss_clean = FALSE)
+	public function get($index = NULL, $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		// Check if a field has been provided
 		if ($index === NULL)
 		{
@@ -229,8 +234,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function post($index = NULL, $xss_clean = FALSE)
+	public function post($index = NULL, $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		// Check if a field has been provided
 		if ($index === NULL)
 		{
@@ -261,8 +268,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function get_post($index = '', $xss_clean = FALSE)
+	public function post_get($index = '', $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		return isset($_POST[$index])
 			? $this->post($index, $xss_clean)
 			: $this->get($index, $xss_clean);
@@ -271,14 +280,34 @@ class CI_Input {
 	// --------------------------------------------------------------------
 
 	/**
+	 * Fetch an item from GET data with fallback to POST
+	 *
+	 * @param	string	$index		Index for item to be fetched from $_GET or $_POST
+	 * @param	bool	$xss_clean	Whether to apply XSS filtering
+	 * @return	mixed
+	 */
+	public function get_post($index = '', $xss_clean = NULL)
+	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
+		return isset($_GET[$index])
+			? $this->get($index, $xss_clean)
+			: $this->post($index, $xss_clean);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
 	 * Fetch an item from the COOKIE array
 	 *
 	 * @param	string	$index		Index for item to be fetched from $_COOKIE
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function cookie($index = '', $xss_clean = FALSE)
+	public function cookie($index = '', $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		return $this->_fetch_from_array($_COOKIE, $index, $xss_clean);
 	}
 
@@ -291,8 +320,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function server($index = '', $xss_clean = FALSE)
+	public function server($index = '', $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		return $this->_fetch_from_array($_SERVER, $index, $xss_clean);
 	}
 
@@ -307,8 +338,10 @@ class CI_Input {
 	 * @param	bool	$xss_clean	Whether to apply XSS filtering
 	 * @return	mixed
 	 */
-	public function input_stream($index = '', $xss_clean = FALSE)
+	public function input_stream($index = '', $xss_clean = NULL)
 	{
+		is_bool($xss_clean) OR $xss_clean = $this->_enable_xss;
+
 		// The input stream can only be read once, so we'll need to check
 		// if we have already done that first.
 		if (is_array($this->_input_stream))
@@ -345,7 +378,7 @@ class CI_Input {
 	 * @param	bool		$httponly	Whether to only makes the cookie accessible via HTTP (no javascript)
 	 * @return	void
 	 */
-	public function set_cookie($name = '', $value = '', $expire = '', $domain = '', $path = '/', $prefix = '', $secure = FALSE, $httponly = FALSE)
+	public function set_cookie($name, $value = '', $expire = '', $domain = '', $path = '/', $prefix = '', $secure = FALSE, $httponly = FALSE)
 	{
 		if (is_array($name))
 		{
@@ -671,13 +704,22 @@ class CI_Input {
 			// but that when present will trip our 'Disallowed Key Characters' alarm
 			// http://www.ietf.org/rfc/rfc2109.txt
 			// note that the key names below are single quoted strings, and are not PHP variables
-			unset($_COOKIE['$Version']);
-			unset($_COOKIE['$Path']);
-			unset($_COOKIE['$Domain']);
+			unset(
+				$_COOKIE['$Version'],
+				$_COOKIE['$Path'],
+				$_COOKIE['$Domain']
+			);
 
 			foreach ($_COOKIE as $key => $val)
 			{
-				$_COOKIE[$this->_clean_input_keys($key)] = $this->_clean_input_data($val);
+				if (($cookie_key = $this->_clean_input_keys($key)) !== FALSE)
+				{
+					$_COOKIE[$cookie_key] = $this->_clean_input_data($val);
+				}
+				else
+				{
+					unset($_COOKIE[$key]);
+				}
 			}
 		}
 
@@ -685,12 +727,12 @@ class CI_Input {
 		$_SERVER['PHP_SELF'] = strip_tags($_SERVER['PHP_SELF']);
 
 		// CSRF Protection check
-		if ($this->_enable_csrf === TRUE && ! $this->is_cli_request())
+		if ($this->_enable_csrf === TRUE && ! is_cli())
 		{
 			$this->security->csrf_verify();
 		}
 
-		log_message('debug', 'Global POST and COOKIE data sanitized');
+		log_message('debug', 'Global POST, GET and COOKIE data sanitized');
 	}
 
 	// --------------------------------------------------------------------
@@ -733,13 +775,7 @@ class CI_Input {
 		}
 
 		// Remove control characters
-		$str = remove_invisible_characters($str);
-
-		// Should we filter the input data?
-		if ($this->_enable_xss === TRUE)
-		{
-			$str = $this->security->xss_clean($str);
-		}
+		$str = remove_invisible_characters($str, FALSE);
 
 		// Standardize newlines if needed
 		if ($this->_standardize_newlines === TRUE)
@@ -760,15 +796,25 @@ class CI_Input {
 	 * only named with alpha-numeric text and a few other items.
 	 *
 	 * @param	string	$str	Input string
-	 * @return	string
+	 * @param	string	$fatal	Whether to terminate script exection
+	 *				or to return FALSE if an invalid
+	 *				key is encountered
+	 * @return	string|bool
 	 */
-	protected function _clean_input_keys($str)
+	protected function _clean_input_keys($str, $fatal = TRUE)
 	{
 		if ( ! preg_match('/^[a-z0-9:_\/|-]+$/i', $str))
 		{
-			set_status_header(503);
-			echo 'Disallowed Key Characters.';
-			exit(EXIT_USER_INPUT);
+			if ($fatal === TRUE)
+			{
+				return FALSE;
+			}
+			else
+			{
+				set_status_header(503);
+				echo 'Disallowed Key Characters.';
+				exit(EXIT_USER_INPUT);
+			}
 		}
 
 		// Clean UTF-8 if supported
@@ -868,11 +914,12 @@ class CI_Input {
 	 *
 	 * Test to see if a request was made from the command line.
 	 *
-	 * @return 	bool
+	 * @deprecated	3.0.0	Use is_cli() instead
+	 * @return      bool
 	 */
 	public function is_cli_request()
 	{
-		return (php_sapi_name() === 'cli' OR defined('STDIN'));
+		return is_cli();
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/core/Lang.php b/system/core/Lang.php
index 3236709f2..290b38bea 100644
--- a/system/core/Lang.php
+++ b/system/core/Lang.php
@@ -166,7 +166,7 @@ class CI_Lang {
 	 * @param	bool	$log_errors	Whether to log an error message if the line is not found
 	 * @return	string	Translation
 	 */
-	public function line($line = '', $log_errors = TRUE)
+	public function line($line, $log_errors = TRUE)
 	{
 		$value = ($line === '' OR ! isset($this->language[$line])) ? FALSE : $this->language[$line];
 
diff --git a/system/core/Loader.php b/system/core/Loader.php
index 70a6b6fa6..8c8d5a37c 100644
--- a/system/core/Loader.php
+++ b/system/core/Loader.php
@@ -76,13 +76,6 @@ class CI_Loader {
 	protected $_ci_helper_paths =	array(APPPATH, BASEPATH);
 
 	/**
-	 * List of loaded base classes
-	 *
-	 * @var	array
-	 */
-	protected $_base_classes =	array(); // Set by the controller class
-
-	/**
 	 * List of cached variables
 	 *
 	 * @var	array
@@ -120,6 +113,8 @@ class CI_Loader {
 		'user_agent' => 'agent'
 	);
 
+	// --------------------------------------------------------------------
+
 	/**
 	 * Class constructor
 	 *
@@ -129,7 +124,8 @@ class CI_Loader {
 	 */
 	public function __construct()
 	{
-		$this->_ci_ob_level  = ob_get_level();
+		$this->_ci_ob_level = ob_get_level();
+		$this->_ci_classes =& is_loaded();
 
 		log_message('debug', 'Loader Class Initialized');
 	}
@@ -147,7 +143,6 @@ class CI_Loader {
 	 */
 	public function initialize()
 	{
-		$this->_base_classes =& is_loaded();
 		$this->_ci_autoloader();
 	}
 
@@ -165,7 +160,7 @@ class CI_Loader {
 	 */
 	public function is_loaded($class)
 	{
-		return isset($this->_ci_classes[$class]) ? $this->_ci_classes[$class] : FALSE;
+		return array_search(ucfirst($class), $this->_ci_classes, TRUE);
 	}
 
 	// --------------------------------------------------------------------
@@ -179,23 +174,29 @@ class CI_Loader {
 	 * @param	string	$library	Library name
 	 * @param	array	$params		Optional parameters to pass to the library class constructor
 	 * @param	string	$object_name	An optional object name to assign to
-	 * @return	void
+	 * @return	object
 	 */
-	public function library($library = '', $params = NULL, $object_name = NULL)
+	public function library($library, $params = NULL, $object_name = NULL)
 	{
-		if (is_array($library))
+		if (empty($library))
+		{
+			return $this;
+		}
+		elseif (is_array($library))
 		{
-			foreach ($library as $class)
+			foreach ($library as $key => $value)
 			{
-				$this->library($class, $params);
+				if (is_int($key))
+				{
+					$this->library($value, $params);
+				}
+				else
+				{
+					$this->library($key, $params, $value);
+				}
 			}
 
-			return;
-		}
-
-		if ($library === '' OR isset($this->_base_classes[$library]))
-		{
-			return;
+			return $this;
 		}
 
 		if ($params !== NULL && ! is_array($params))
@@ -204,6 +205,7 @@ class CI_Loader {
 		}
 
 		$this->_ci_load_class($library, $params, $object_name);
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -216,21 +218,22 @@ class CI_Loader {
 	 * @param	string	$model		Model name
 	 * @param	string	$name		An optional object name to assign to
 	 * @param	bool	$db_conn	An optional database connection configuration to initialize
-	 * @return	void
+	 * @return	object
 	 */
 	public function model($model, $name = '', $db_conn = FALSE)
 	{
 		if (empty($model))
 		{
-			return;
+			return $this;
 		}
 		elseif (is_array($model))
 		{
 			foreach ($model as $key => $value)
 			{
-				$this->model(is_int($key) ? $value : $key, $value);
+				is_int($key) ? $this->model($value, '', $db_conn) : $this->model($key, $value, $db_conn);
 			}
-			return;
+
+			return $this;
 		}
 
 		$path = '';
@@ -252,7 +255,7 @@ class CI_Loader {
 
 		if (in_array($name, $this->_ci_models, TRUE))
 		{
-			return;
+			return $this;
 		}
 
 		$CI =& get_instance();
@@ -261,36 +264,35 @@ class CI_Loader {
 			show_error('The model name you are loading is the name of a resource that is already being used: '.$name);
 		}
 
-		$model = strtolower($model);
-
-		foreach ($this->_ci_model_paths as $mod_path)
+		if ($db_conn !== FALSE && ! class_exists('CI_DB', FALSE))
 		{
-			if ( ! file_exists($mod_path.'models/'.$path.$model.'.php'))
+			if ($db_conn === TRUE)
 			{
-				continue;
+				$db_conn = '';
 			}
 
-			if ($db_conn !== FALSE && ! class_exists('CI_DB', FALSE))
-			{
-				if ($db_conn === TRUE)
-				{
-					$db_conn = '';
-				}
+			$CI->load->database($db_conn, FALSE, TRUE);
+		}
 
-				$CI->load->database($db_conn, FALSE, TRUE);
-			}
+		if ( ! class_exists('CI_Model', FALSE))
+		{
+			load_class('Model', 'core');
+		}
 
-			if ( ! class_exists('CI_Model', FALSE))
+		$model = ucfirst(strtolower($model));
+
+		foreach ($this->_ci_model_paths as $mod_path)
+		{
+			if ( ! file_exists($mod_path.'models/'.$path.$model.'.php'))
 			{
-				load_class('Model', 'core');
+				continue;
 			}
 
 			require_once($mod_path.'models/'.$path.$model.'.php');
 
-			$model = ucfirst($model);
 			$CI->$name = new $model();
 			$this->_ci_models[] = $name;
-			return;
+			return $this;
 		}
 
 		// couldn't find the model
@@ -307,8 +309,8 @@ class CI_Loader {
 	 * @param	bool	$query_builder	Whether to enable Query Builder
 	 *					(overrides the configuration setting)
 	 *
-	 * @return	void|object|bool	Database object if $return is set to TRUE,
-	 *					FALSE on failure, void in any other case
+	 * @return	object|bool	Database object if $return is set to TRUE,
+	 *					FALSE on failure, CI_Loader instance in any other case
 	 */
 	public function database($params = '', $return = FALSE, $query_builder = NULL)
 	{
@@ -334,6 +336,7 @@ class CI_Loader {
 
 		// Load the DB class
 		$CI->db =& DB($params, $query_builder);
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -342,8 +345,8 @@ class CI_Loader {
 	 * Load the Database Utilities Class
 	 *
 	 * @param	object	$db	Database object
-	 * @param	bool	$return	Whether to return the DB Forge class object or not
-	 * @return	void|object
+	 * @param	bool	$return	Whether to return the DB Utilities class object or not
+	 * @return	object
 	 */
 	public function dbutil($db = NULL, $return = FALSE)
 	{
@@ -365,6 +368,7 @@ class CI_Loader {
 		}
 
 		$CI->dbutil = new $class($db);
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -374,7 +378,7 @@ class CI_Loader {
 	 *
 	 * @param	object	$db	Database object
 	 * @param	bool	$return	Whether to return the DB Forge class object or not
-	 * @return	void|object
+	 * @return	object
 	 */
 	public function dbforge($db = NULL, $return = FALSE)
 	{
@@ -408,6 +412,7 @@ class CI_Loader {
 		}
 
 		$CI->dbforge = new $class($db);
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -422,7 +427,7 @@ class CI_Loader {
 	 *				to be extracted for use in the view
 	 * @param	bool	$return	Whether to return the view output
 	 *				or leave it to the Output class
-	 * @return	void
+	 * @return	object|string
 	 */
 	public function view($view, $vars = array(), $return = FALSE)
 	{
@@ -436,7 +441,7 @@ class CI_Loader {
 	 *
 	 * @param	string	$path	File path
 	 * @param	bool	$return	Whether to return the file output
-	 * @return	void|string
+	 * @return	object|string
 	 */
 	public function file($path, $return = FALSE)
 	{
@@ -455,9 +460,9 @@ class CI_Loader {
 	 *					An associative array or object containing values
 	 *					to be set, or a value's name if string
 	 * @param 	string	$val	Value to set, only used if $vars is a string
-	 * @return	void
+	 * @return	object
 	 */
-	public function vars($vars = array(), $val = '')
+	public function vars($vars, $val = '')
 	{
 		if (is_string($vars))
 		{
@@ -473,6 +478,23 @@ class CI_Loader {
 				$this->_ci_cached_vars[$key] = $val;
 			}
 		}
+
+		return $this;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Clear Cached Variables
+	 *
+	 * Clears the cached variables.
+	 *
+	 * @return  object
+	 */
+	public function clear_vars()
+	{
+		$this->_ci_cached_vars = array();
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -510,7 +532,7 @@ class CI_Loader {
 	 * Helper Loader
 	 *
 	 * @param	string|string[]	$helpers	Helper name(s)
-	 * @return	void
+	 * @return	object
 	 */
 	public function helper($helpers = array())
 	{
@@ -567,6 +589,8 @@ class CI_Loader {
 				show_error('Unable to load the requested file: helpers/'.$helper.'.php');
 			}
 		}
+
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -579,11 +603,11 @@ class CI_Loader {
 	 *
 	 * @uses	CI_Loader::helper()
 	 * @param	string|string[]	$helpers	Helper name(s)
-	 * @return	void
+	 * @return	object
 	 */
 	public function helpers($helpers = array())
 	{
-		$this->helper($helpers);
+		return $this->helper($helpers);
 	}
 
 	// --------------------------------------------------------------------
@@ -595,18 +619,19 @@ class CI_Loader {
 	 *
 	 * @param	string|string[]	$files	List of language file names to load
 	 * @param	string		Language name
-	 * @return	void
+	 * @return	object
 	 */
-	public function language($files = array(), $lang = '')
+	public function language($files, $lang = '')
 	{
 		$CI =& get_instance();
-
 		is_array($files) OR $files = array($files);
 
 		foreach ($files as $langfile)
 		{
 			$CI->lang->load($langfile, $lang);
 		}
+
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -622,10 +647,9 @@ class CI_Loader {
 	 * @param	bool	$fail_gracefully	Whether to just return FALSE or display an error message
 	 * @return	bool	TRUE if the file was loaded correctly or FALSE on failure
 	 */
-	public function config($file = '', $use_sections = FALSE, $fail_gracefully = FALSE)
+	public function config($file, $use_sections = FALSE, $fail_gracefully = FALSE)
 	{
-		$CI =& get_instance();
-		return $CI->config->load($file, $use_sections, $fail_gracefully);
+		return get_instance()->config->load($file, $use_sections, $fail_gracefully);
 	}
 
 	// --------------------------------------------------------------------
@@ -639,10 +663,10 @@ class CI_Loader {
 	 * @param	array		$params		Optional parameters to pass to the driver
 	 * @param	string		$object_name	An optional object name to assign to
 	 *
-	 * @return	void|object|bool	Object or FALSE on failure if $library is a string
-	 *					and $object_name is set. void otherwise.
+	 * @return	object|bool	Object or FALSE on failure if $library is a string
+	 *				and $object_name is set. CI_Loader instance otherwise.
 	 */
-	public function driver($library = '', $params = NULL, $object_name = NULL)
+	public function driver($library, $params = NULL, $object_name = NULL)
 	{
 		if (is_array($library))
 		{
@@ -650,10 +674,10 @@ class CI_Loader {
 			{
 				$this->driver($driver);
 			}
-			return;
-		}
 
-		if ($library === '')
+			return $this;
+		}
+		elseif (empty($library))
 		{
 			return FALSE;
 		}
@@ -689,7 +713,7 @@ class CI_Loader {
 	 *
 	 * @param	string	$path		Path to add
 	 * @param 	bool	$view_cascade	(default: TRUE)
-	 * @return	void
+	 * @return	object
 	 */
 	public function add_package_path($path, $view_cascade = TRUE)
 	{
@@ -704,6 +728,8 @@ class CI_Loader {
 		// Add config file path
 		$config =& $this->_ci_get_component('config');
 		$config->_config_paths[] = $path;
+
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -731,7 +757,7 @@ class CI_Loader {
 	 * added path will be removed removed.
 	 *
 	 * @param	string	$path	Path to remove
-	 * @return	void
+	 * @return	object
 	 */
 	public function remove_package_path($path = '')
 	{
@@ -773,6 +799,8 @@ class CI_Loader {
 		$this->_ci_model_paths = array_unique(array_merge($this->_ci_model_paths, array(APPPATH)));
 		$this->_ci_view_paths = array_merge($this->_ci_view_paths, array(APPPATH.'views/' => TRUE));
 		$config->_config_paths = array_unique(array_merge($config->_config_paths, array(APPPATH)));
+
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -788,7 +816,7 @@ class CI_Loader {
 	 * @used-by	CI_Loader::view()
 	 * @used-by	CI_Loader::file()
 	 * @param	array	$_ci_data	Data to load
-	 * @return	void
+	 * @return	object
 	 */
 	protected function _ci_load($_ci_data)
 	{
@@ -912,6 +940,8 @@ class CI_Loader {
 			$_ci_CI->output->append_output(ob_get_contents());
 			@ob_end_clean();
 		}
+
+		return $this;
 	}
 
 	// --------------------------------------------------------------------
@@ -1118,30 +1148,35 @@ class CI_Loader {
 
 		// Set the variable name we will assign the class to
 		// Was a custom class name supplied? If so we'll use it
-		$class = strtolower($class);
-
-		if ($object_name === NULL)
+		if (empty($object_name))
 		{
-			$classvar = isset($this->_ci_varmap[$class]) ? $this->_ci_varmap[$class] : $class;
+			$object_name = strtolower($class);
+			if (isset($this->_ci_varmap[$object_name]))
+			{
+				$object_name = $this->_ci_varmap[$object_name];
+			}
 		}
-		else
+
+		// Don't overwrite existing properties
+		$CI =& get_instance();
+		if (isset($CI->$object_name))
 		{
-			$classvar = $object_name;
+			if ($CI->$object_name instanceof $name)
+			{
+				log_message('debug', $class." has already been instantiated as '".$object_name."'. Second attempt aborted.");
+				return;
+			}
+
+			show_error("Resource '".$object_name."' already exists and is not a ".$class." instance.");
 		}
 
 		// Save the class name and object name
-		$this->_ci_classes[$class] = $classvar;
+		$this->_ci_classes[$object_name] = $class;
 
 		// Instantiate the class
-		$CI =& get_instance();
-		if ($config !== NULL)
-		{
-			$CI->$classvar = new $name($config);
-		}
-		else
-		{
-			$CI->$classvar = new $name();
-		}
+		$CI->$object_name = isset($config)
+			? new $name($config)
+			: new $name();
 	}
 
 	// --------------------------------------------------------------------
@@ -1198,6 +1233,15 @@ class CI_Loader {
 			}
 		}
 
+		// Autoload drivers
+		if (isset($autoload['drivers']))
+		{
+			foreach ($autoload['drivers'] as $item)
+			{
+				$this->driver($item);
+			}
+		}
+
 		// Load libraries
 		if (isset($autoload['libraries']) && count($autoload['libraries']) > 0)
 		{
@@ -1215,15 +1259,6 @@ class CI_Loader {
 			}
 		}
 
-		// Autoload drivers
-		if (isset($autoload['drivers']))
-		{
-			foreach ($autoload['drivers'] as $item)
-			{
-				$this->driver($item);
-			}
-		}
-
 		// Autoload models
 		if (isset($autoload['model']))
 		{
diff --git a/system/core/Log.php b/system/core/Log.php
index e4d72b544..63fef2088 100644
--- a/system/core/Log.php
+++ b/system/core/Log.php
@@ -140,10 +140,9 @@ class CI_Log {
 	 *
 	 * @param	string	the error level: 'error', 'debug' or 'info'
 	 * @param	string	the error message
-	 * @param	bool	whether the error is a native PHP error
 	 * @return	bool
 	 */
-	public function write_log($level, $msg, $php_error = FALSE)
+	public function write_log($level, $msg)
 	{
 		if ($this->_enabled === FALSE)
 		{
@@ -176,10 +175,18 @@ class CI_Log {
 			return FALSE;
 		}
 
-		$message .= $level.' '.($level === 'INFO' ? ' -' : '-').' '.date($this->_date_fmt).' --> '.$msg."\n";
+		$message .= $level.' - '.date($this->_date_fmt).' --> '.$msg."\n";
 
 		flock($fp, LOCK_EX);
-		fwrite($fp, $message);
+
+		for ($written = 0, $length = strlen($message); $written < $length; $written += $result)
+		{
+			if (($result = fwrite($fp, substr($message, $written))) === FALSE)
+			{
+				break;
+			}
+		}
+
 		flock($fp, LOCK_UN);
 		fclose($fp);
 
@@ -188,7 +195,7 @@ class CI_Log {
 			@chmod($filepath, FILE_WRITE_MODE);
 		}
 
-		return TRUE;
+		return is_int($result);
 	}
 
 }
diff --git a/system/core/Model.php b/system/core/Model.php
index 1eb6f909b..11e60759b 100644
--- a/system/core/Model.php
+++ b/system/core/Model.php
@@ -59,8 +59,7 @@ class CI_Model {
 	 */
 	public function __get($key)
 	{
-		$CI =& get_instance();
-		return $CI->$key;
+		return get_instance()->$key;
 	}
 
 }
diff --git a/system/core/Output.php b/system/core/Output.php
index 06d7a866b..2ad8e90fa 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -58,21 +58,21 @@ class CI_Output {
 	 *
 	 * @var	array
 	 */
-	public $headers =	array();
+	public $headers = array();
 
 	/**
 	 * List of mime types
 	 *
 	 * @var	array
 	 */
-	public $mimes =		array();
+	public $mimes =	array();
 
 	/**
 	 * Mime-type for the current page
 	 *
 	 * @var	string
 	 */
-	protected $mime_type	= 'text/html';
+	protected $mime_type = 'text/html';
 
 	/**
 	 * Enable Profiler flag
@@ -82,11 +82,18 @@ class CI_Output {
 	public $enable_profiler = FALSE;
 
 	/**
-	 * zLib output compression flag
+	 * php.ini zlib.output_compression flag
 	 *
 	 * @var	bool
 	 */
-	protected $_zlib_oc =		FALSE;
+	protected $_zlib_oc = FALSE;
+
+	/**
+	 * CI output compression flag
+	 *
+	 * @var	bool
+	 */
+	protected $_compress_output = FALSE;
 
 	/**
 	 * List of profiler sections
@@ -102,7 +109,7 @@ class CI_Output {
 	 *
 	 * @var	bool
 	 */
-	public $parse_exec_vars =	TRUE;
+	public $parse_exec_vars = TRUE;
 
 	/**
 	 * Class constructor
@@ -114,6 +121,11 @@ class CI_Output {
 	public function __construct()
 	{
 		$this->_zlib_oc = (bool) @ini_get('zlib.output_compression');
+		$this->_compress_output = (
+			$this->_zlib_oc === FALSE
+			&& config_item('compress_output') === TRUE
+			&& extension_loaded('zlib')
+		);
 
 		// Get mime types for later
 		$this->mimes =& get_mimes();
@@ -436,15 +448,14 @@ class CI_Output {
 		if ($this->parse_exec_vars === TRUE)
 		{
 			$memory	= round(memory_get_usage() / 1024 / 1024, 2).'MB';
-
 			$output = str_replace(array('{elapsed_time}', '{memory_usage}'), array($elapsed, $memory), $output);
 		}
 
 		// --------------------------------------------------------------------
 
 		// Is compression requested?
-		if ($CFG->item('compress_output') === TRUE && $this->_zlib_oc === FALSE
-			&& extension_loaded('zlib')
+		if (isset($CI) // This means that we're not serving a cache file, if we were, it would already be compressed
+			&& $this->_compress_output === TRUE
 			&& isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE)
 		{
 			ob_start('ob_gzhandler');
@@ -468,6 +479,21 @@ class CI_Output {
 		// simply echo out the data and exit.
 		if ( ! isset($CI))
 		{
+			if ($this->_compress_output === TRUE)
+			{
+				if (isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE)
+				{
+					header('Content-Encoding: gzip');
+					header('Content-Length: '.strlen($output));
+				}
+				else
+				{
+					// User agent doesn't support gzip compression,
+					// so we'll have to decompress our cache
+					$output = gzinflate(substr($output, 10, -8));
+				}
+			}
+
 			echo $output;
 			log_message('debug', 'Final output sent to browser');
 			log_message('debug', 'Total execution time: '.$elapsed);
@@ -530,9 +556,9 @@ class CI_Output {
 			return;
 		}
 
-		$uri =	$CI->config->item('base_url').
-				$CI->config->item('index_page').
-				$CI->uri->uri_string();
+		$uri = $CI->config->item('base_url')
+			.$CI->config->item('index_page')
+			.$CI->uri->uri_string();
 
 		$cache_path .= md5($uri);
 
@@ -542,17 +568,39 @@ class CI_Output {
 			return;
 		}
 
-		$expire = time() + ($this->cache_expiration * 60);
-
-		// Put together our serialized info.
-		$cache_info = serialize(array(
-			'expire'	=> $expire,
-			'headers'	=> $this->headers
-		));
-
 		if (flock($fp, LOCK_EX))
 		{
-			fwrite($fp, $cache_info.'ENDCI--->'.$output);
+			// If output compression is enabled, compress the cache
+			// itself, so that we don't have to do that each time
+			// we're serving it
+			if ($this->_compress_output === TRUE)
+			{
+				$output = gzencode($output);
+
+				if ($this->get_header('content-type') === NULL)
+				{
+					$this->set_content_type($this->mime_type);
+				}
+			}
+
+			$expire = time() + ($this->cache_expiration * 60);
+
+			// Put together our serialized info.
+			$cache_info = serialize(array(
+				'expire'	=> $expire,
+				'headers'	=> $this->headers
+			));
+
+			$output = $cache_info.'ENDCI--->'.$output;
+
+			for ($written = 0, $length = strlen($output); $written < $length; $written += $result)
+			{
+				if (($result = fwrite($fp, substr($output, $written))) === FALSE)
+				{
+					break;
+				}
+			}
+
 			flock($fp, LOCK_UN);
 		}
 		else
@@ -560,13 +608,22 @@ class CI_Output {
 			log_message('error', 'Unable to secure a file lock for file at: '.$cache_path);
 			return;
 		}
+
 		fclose($fp);
-		@chmod($cache_path, FILE_WRITE_MODE);
 
-		log_message('debug', 'Cache file written: '.$cache_path);
+		if (is_int($result))
+		{
+			@chmod($cache_path, FILE_WRITE_MODE);
+			log_message('debug', 'Cache file written: '.$cache_path);
 
-		// Send HTTP cache-control headers to browser to match file cache settings.
-		$this->set_cache_header($_SERVER['REQUEST_TIME'], $expire);
+			// Send HTTP cache-control headers to browser to match file cache settings.
+			$this->set_cache_header($_SERVER['REQUEST_TIME'], $expire);
+		}
+		else
+		{
+			@unlink($cache_path);
+			log_message('error', 'Unable to write the complete cache content at: '.$cache_path);
+		}
 	}
 
 	// --------------------------------------------------------------------
@@ -701,7 +758,7 @@ class CI_Output {
 		else
 		{
 			header('Pragma: public');
-			header('Cache-Control: max-age=' . $max_age . ', public');
+			header('Cache-Control: max-age='.$max_age.', public');
 			header('Expires: '.gmdate('D, d M Y H:i:s', $expiration).' GMT');
 			header('Last-modified: '.gmdate('D, d M Y H:i:s', $last_modified).' GMT');
 		}
@@ -740,13 +797,13 @@ class CI_Output {
 				preg_match_all('{<style.+</style>}msU', $output, $style_clean);
 				foreach ($style_clean[0] as $s)
 				{
-					$output = str_replace($s, $this->_minify_script_style($s, TRUE), $output);
+					$output = str_replace($s, $this->_minify_js_css($s, 'css', TRUE), $output);
 				}
 
 				// Minify the javascript in <script> tags.
 				foreach ($javascript_clean[0] as $s)
 				{
-					$javascript_mini[] = $this->_minify_script_style($s, TRUE);
+					$javascript_mini[] = $this->_minify_js_css($s, 'js', TRUE);
 				}
 
 				// Replace multiple spaces with a single space.
@@ -792,13 +849,14 @@ class CI_Output {
 			break;
 
 			case 'text/css':
+
+				return $this->_minify_js_css($output, 'css');
+
 			case 'text/javascript':
 			case 'application/javascript':
 			case 'application/x-javascript':
 
-				$output = $this->_minify_script_style($output);
-
-			break;
+				return $this->_minify_js_css($output, 'js');
 
 			default: break;
 		}
@@ -809,134 +867,100 @@ class CI_Output {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Minify Style and Script
-	 *
-	 * Reduce excessive size of CSS/JavaScript content.  To remove spaces this
-	 * script walks the string as an array and determines if the pointer is inside
-	 * a string created by single quotes or double quotes.  spaces inside those
-	 * strings are not stripped.  Opening and closing tags are severed from
-	 * the string initially and saved without stripping whitespace to preserve
-	 * the tags and any associated properties if tags are present
+	 * Minify JavaScript and CSS code
 	 *
-	 * Minification logic/workflow is similar to methods used by Douglas Crockford
-	 * in JSMIN. http://www.crockford.com/javascript/jsmin.html
+	 * Strips comments and excessive whitespace characters
 	 *
-	 * KNOWN ISSUE: ending a line with a closing parenthesis ')' and no semicolon
-	 * where there should be one will break the Javascript. New lines after a
-	 * closing parenthesis are not recognized by the script. For best results
-	 * be sure to terminate lines with a semicolon when appropriate.
-	 *
-	 * @param	string	$output		Output to minify
-	 * @param	bool	$has_tags	Specify if the output has style or script tags
-	 * @return	string	Minified output
+	 * @param	string	$output
+	 * @param	string	$type	'js' or 'css'
+	 * @param	bool	$tags	Whether $output contains the 'script' or 'style' tag
+	 * @return	string
 	 */
-	protected function _minify_script_style($output, $has_tags = FALSE)
+	protected function _minify_js_css($output, $type, $tags = FALSE)
 	{
-		// We only need this if there are tags in the file
-		if ($has_tags === TRUE)
+		if ($tags === TRUE)
 		{
-			// Remove opening tag and save for later
-			$pos = strpos($output, '>') + 1;
-			$open_tag = substr($output, 0, $pos);
-			$output = substr_replace($output, '', 0, $pos);
+			$tags = array('close' => strrchr($output, '<'));
 
-			// Remove closing tag and save it for later
-			$pos = strpos($output, '</');
-			$closing_tag = substr($output, $pos, strlen($output));
-			$output = substr_replace($output, '', $pos);
-		}
+			$open_length = strpos($output, '>') + 1;
+			$tags['open'] = substr($output, 0, $open_length);
 
-		// Remove CSS comments
-		$output = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!i', '', $output);
+			$output = substr($output, $open_length, -strlen($tags['close']));
 
-		// Remove spaces around curly brackets, colons,
-		// semi-colons, parenthesis, commas
-		$chunks = preg_split('/([\'|"]).+(?![^\\\]\\1)\\1/iU', $output, -1, PREG_SPLIT_OFFSET_CAPTURE);
-		for ($i = count($chunks) - 1; $i >= 0; $i--)
-		{
-			$output = substr_replace(
-				$output,
-				preg_replace('/\s*(:|;|,|}|{|\(|\))\s*/i', '$1', $chunks[$i][0]),
-				$chunks[$i][1],
-				strlen($chunks[$i][0])
-			);
+			// Strip spaces from the tags
+			$tags = preg_replace('#\s{2,}#', ' ', $tags);
 		}
 
-		// Replace tabs with spaces
-		// Replace carriage returns & multiple new lines with single new line
-		// and trim any leading or trailing whitespace
-		$output = trim(preg_replace(array('/\t+/', '/\r/', '/\n+/'), array(' ', "\n", "\n"), $output));
+		$output = trim($output);
 
-		// Remove spaces when safe to do so.
-		$in_string = $in_dstring = $prev = FALSE;
-		$array_output = str_split($output);
-		foreach ($array_output as $key => $value)
+		if ($type === 'js')
 		{
-			if ($in_string === FALSE && $in_dstring === FALSE)
+			// Catch all string literals and comment blocks
+			if (preg_match_all('#((?:((?<!\\\)\'|")|(/\*)|(//)).*(?(2)(?<!\\\)\2|(?(3)\*/|\n)))#msuUS', $output, $match, PREG_OFFSET_CAPTURE))
 			{
-				if ($value === ' ')
+				$js_literals = $js_code = array();
+				for ($match = $match[0], $c = count($match), $i = $pos = $offset = 0; $i < $c; $i++)
 				{
-					// Get the next element in the array for comparisons
-					$next = $array_output[$key + 1];
-
-					// Strip spaces preceded/followed by a non-ASCII character
-					// or not preceded/followed by an alphanumeric
-					// or not preceded/followed \ $ and _
-					if ((preg_match('/^[\x20-\x7f]*$/D', $next) OR preg_match('/^[\x20-\x7f]*$/D', $prev))
-						&& ( ! ctype_alnum($next) OR ! ctype_alnum($prev))
-						&& ! in_array($next, array('\\', '_', '$'), TRUE)
-						&& ! in_array($prev, array('\\', '_', '$'), TRUE)
-					)
+					$js_code[$pos++] = trim(substr($output, $offset, $match[$i][1] - $offset));
+					$offset = $match[$i][1] + strlen($match[$i][0]);
+
+					// Save only if we haven't matched a comment block
+					if ($match[$i][0][0] !== '/')
 					{
-						unset($array_output[$key]);
+						$js_literals[$pos++] = array_shift($match[$i]);
 					}
 				}
-				else
-				{
-					// Save this value as previous for the next iteration
-					// if it is not a blank space
-					$prev = $value;
-				}
-			}
+				$js_code[$pos] = substr($output, $offset);
 
-			if ($value === "'")
-			{
-				$in_string = ! $in_string;
+				// $match might be quite large, so free it up together with other vars that we no longer need
+				unset($match, $offset, $pos);
 			}
-			elseif ($value === '"')
+			else
 			{
-				$in_dstring = ! $in_dstring;
+				$js_code = array($output);
+				$js_literals = array();
 			}
+
+			$varname = 'js_code';
+		}
+		else
+		{
+			$varname = 'output';
 		}
 
-		// Put the string back together after spaces have been stripped
-		$output = implode($array_output);
+		// Standartize new lines
+		$$varname = str_replace(array("\r\n", "\r"), "\n", $$varname);
 
-		// Remove new line characters unless previous or next character is
-		// printable or Non-ASCII
-		preg_match_all('/[\n]/', $output, $lf, PREG_OFFSET_CAPTURE);
-		$removed_lf = 0;
-		foreach ($lf as $feed_position)
+		if ($type === 'js')
 		{
-			foreach ($feed_position as $position)
-			{
-				$position = $position[1] - $removed_lf;
-				$next = $output[$position + 1];
-				$prev = $output[$position - 1];
-				if ( ! ctype_print($next) && ! ctype_print($prev)
-					&& ! preg_match('/^[\x20-\x7f]*$/D', $next)
-					&& ! preg_match('/^[\x20-\x7f]*$/D', $prev)
-				)
-				{
-					$output = substr_replace($output, '', $position, 1);
-					$removed_lf++;
-				}
-			}
+			$patterns = array(
+				'#\s*([!\#%&()*+,\-./:;<=>?@\[\]^`{|}~])\s*#'	=> '$1',	// Remove spaces following and preceeding JS-wise non-special & non-word characters
+				'#\s{2,}#'					=> ' '		// Reduce the remaining multiple whitespace characters to a single space
+			);
+		}
+		else
+		{
+			$patterns = array(
+				'#/\*.*(?=\*/)\*/#s'	=> '',		// Remove /* block comments */
+				'#\n?//[^\n]*#'		=> '',		// Remove // line comments
+				'#\s*([^\w.\#%])\s*#U'	=> '$1',	// Remove spaces following and preceeding non-word characters, excluding dots, hashes and the percent sign
+				'#\s{2,}#'		=> ' '		// Reduce the remaining multiple space characters to a single space
+			);
+		}
+
+		$$varname = preg_replace(array_keys($patterns), array_values($patterns), $$varname);
+
+		// Glue back JS quoted strings
+		if ($type === 'js')
+		{
+			$js_code += $js_literals;
+			ksort($js_code);
+			$output = implode($js_code);
+			unset($js_code, $js_literals, $varname, $patterns);
 		}
 
-		// Put the opening and closing tags back if applicable
-		return isset($open_tag)
-			? $open_tag.$output.$closing_tag
+		return is_array($tags)
+			? $tags['open'].$output.$tags['close']
 			: $output;
 	}
 
diff --git a/system/core/Router.php b/system/core/Router.php
index cc3916f86..633524023 100644
--- a/system/core/Router.php
+++ b/system/core/Router.php
@@ -91,6 +91,15 @@ class CI_Router {
 	 */
 	public $translate_uri_dashes = FALSE;
 
+	/**
+	 * Enable query strings flag
+	 *
+	 * Determines wether to use GET parameters or segment URIs
+	 *
+	 * @var	bool
+	 */
+	public $enable_query_strings = FALSE;
+
 	// --------------------------------------------------------------------
 
 	/**
@@ -102,9 +111,34 @@ class CI_Router {
 	 */
 	public function __construct()
 	{
+		global $routing;
+
 		$this->config =& load_class('Config', 'core');
 		$this->uri =& load_class('URI', 'core');
+
+		$this->enable_query_strings = ( ! is_cli() && $this->config->item('enable_query_strings') === TRUE);
 		$this->_set_routing();
+
+		// Set any routing overrides that may exist in the main index file
+		if (isset($routing) && is_array($routing))
+		{
+			if (isset($routing['directory']))
+			{
+				$this->set_directory($routing['directory']);
+			}
+
+			if ( ! empty($routing['controller']))
+			{
+				$this->set_class($routing['controller']);
+			}
+
+			if (isset($routing['function']))
+			{
+				$routing['function'] = empty($routing['function']) ? 'index' : $routing['function'];
+				$this->set_method($routing['function']);
+			}
+		}
+
 		log_message('debug', 'Router Class Initialized');
 	}
 
@@ -123,26 +157,39 @@ class CI_Router {
 		// Are query strings enabled in the config file? Normally CI doesn't utilize query strings
 		// since URI segments are more search-engine friendly, but they can optionally be used.
 		// If this feature is enabled, we will gather the directory/class/method a little differently
-		$segments = array();
-		if ($this->config->item('enable_query_strings') === TRUE
-			&& ! empty($_GET[$this->config->item('controller_trigger')])
-			&& is_string($_GET[$this->config->item('controller_trigger')])
-		)
+		if ($this->enable_query_strings)
 		{
-			if (isset($_GET[$this->config->item('directory_trigger')]) && is_string($_GET[$this->config->item('directory_trigger')]))
+			$_d = $this->config->item('directory_trigger');
+			$_d = isset($_GET[$_d]) ? trim($_GET[$_d], " \t\n\r\0\x0B/") : '';
+			if ($_d !== '')
 			{
-				$this->set_directory(trim($this->uri->_filter_uri($_GET[$this->config->item('directory_trigger')])));
-				$segments[] = $this->directory;
+				$this->set_directory($this->uri->filter_uri($_d));
 			}
 
-			$this->set_class(trim($this->uri->_filter_uri($_GET[$this->config->item('controller_trigger')])));
-			$segments[] = $this->class;
+			$_c = $this->config->item('controller_trigger');
+			if ( ! empty($_GET[$_c]))
+			{
+				$this->set_class(trim($this->uri->filter_uri(trim($_GET[$_c]))));
+
+				$_f = $this->config->item('function_trigger');
+				if ( ! empty($_GET[$_f]))
+				{
+					$this->set_method(trim($this->uri->filter_uri($_GET[$_f])));
+				}
 
-			if ( ! empty($_GET[$this->config->item('function_trigger')]) && is_string($_GET[$this->config->item('function_trigger')]))
+				$this->uri->rsegments = array(
+					1 => $this->class,
+					2 => $this->method
+				);
+			}
+			else
 			{
-				$this->set_method(trim($this->uri->_filter_uri($_GET[$this->config->item('function_trigger')])));
-				$segments[] = $this->method;
+				$this->_set_default_controller();
 			}
+
+			// Routing rules don't apply to query strings and we don't need to detect
+			// directories, so we're done here
+			return;
 		}
 
 		// Load the routes.php file.
@@ -165,53 +212,15 @@ class CI_Router {
 			$this->routes = $route;
 		}
 
-		// Were there any query string segments? If so, we'll validate them and bail out since we're done.
-		if (count($segments) > 0)
+		// Is there anything to parse?
+		if ($this->uri->uri_string !== '')
 		{
-			return $this->_validate_request($segments);
+			$this->_parse_routes();
 		}
-
-		// Fetch the complete URI string
-		$this->uri->_fetch_uri_string();
-
-		// Is there a URI string? If not, the default controller specified in the "routes" file will be shown.
-		if ($this->uri->uri_string == '')
+		else
 		{
-			return $this->_set_default_controller();
+			$this->_set_default_controller();
 		}
-
-		$this->uri->_remove_url_suffix(); // Remove the URL suffix
-		$this->uri->_explode_segments(); // Compile the segments into an array
-		$this->_parse_routes(); // Parse any custom routing that may exist
-		$this->uri->_reindex_segments(); // Re-index the segment array so that it starts with 1 rather than 0
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Set default controller
-	 *
-	 * @return	void
-	 */
-	protected function _set_default_controller()
-	{
-		if (empty($this->default_controller))
-		{
-			show_error('Unable to determine what should be displayed. A default route has not been specified in the routing file.');
-		}
-
-		// Is the method being specified?
-		if (sscanf($this->default_controller, '%[^/]/%s', $class, $method) !== 2)
-		{
-			$method = 'index';
-		}
-
-		$this->_set_request(array($class, $method));
-
-		// re-index the routed segments array so it starts with 1 rather than 0
-		$this->uri->_reindex_segments();
-
-		log_message('debug', 'No URI present. Default controller set.');
 	}
 
 	// --------------------------------------------------------------------
@@ -222,16 +231,19 @@ class CI_Router {
 	 * Takes an array of URI segments as input and sets the class/method
 	 * to be called.
 	 *
+	 * @used-by	CI_Router::_parse_routes()
 	 * @param	array	$segments	URI segments
 	 * @return	void
 	 */
 	protected function _set_request($segments = array())
 	{
 		$segments = $this->_validate_request($segments);
-
-		if (count($segments) === 0)
+		// If we don't have any segments left - try the default controller;
+		// WARNING: Directories get shifted out of the segments array!
+		if (empty($segments))
 		{
-			return $this->_set_default_controller();
+			$this->_set_default_controller();
+			return;
 		}
 
 		if ($this->translate_uri_dashes === TRUE)
@@ -244,92 +256,86 @@ class CI_Router {
 		}
 
 		$this->set_class($segments[0]);
-		isset($segments[1]) OR $segments[1] = 'index';
-		$this->set_method($segments[1]);
+		if (isset($segments[1]))
+		{
+			$this->set_method($segments[1]);
+		}
 
-		// Update our "routed" segment array to contain the segments.
-		// Note: If there is no custom routing, this array will be
-		// identical to $this->uri->segments
+		array_unshift($segments, NULL);
+		unset($segments[0]);
 		$this->uri->rsegments = $segments;
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Validate request
-	 *
-	 * Attempts validate the URI request and determine the controller path.
+	 * Set default controller
 	 *
-	 * @param	array	$segments	URI segments
-	 * @return	array	URI segments
+	 * @return	void
 	 */
-	protected function _validate_request($segments)
+	protected function _set_default_controller()
 	{
-		if (count($segments) === 0)
+		if (empty($this->default_controller))
 		{
-			return $segments;
+			show_error('Unable to determine what should be displayed. A default route has not been specified in the routing file.');
 		}
 
-		$test = ($this->translate_uri_dashes === TRUE)
-			? str_replace('-', '_', $segments[0]) : $segments[0];
-
-		// Does the requested controller exist in the root folder?
-		if (file_exists(APPPATH.'controllers/'.$test.'.php'))
+		// Is the method being specified?
+		if (sscanf($this->default_controller, '%[^/]/%s', $class, $method) !== 2)
 		{
-			return $segments;
+			$method = 'index';
 		}
 
-		// Is the controller in a sub-folder?
-		if (is_dir(APPPATH.'controllers/'.$segments[0]))
+		if ( ! file_exists(APPPATH.'controllers/'.$this->directory.ucfirst($class).'.php'))
 		{
-			// Set the directory and remove it from the segment array
-			$this->set_directory(array_shift($segments));
-			if (count($segments) > 0)
-			{
-				$test = ($this->translate_uri_dashes === TRUE)
-					? str_replace('-', '_', $segments[0]) : $segments[0];
+			// This will trigger 404 later
+			return;
+		}
 
-				// Does the requested controller exist in the sub-directory?
-				if ( ! file_exists(APPPATH.'controllers/'.$this->directory.$test.'.php'))
-				{
-					if ( ! empty($this->routes['404_override']))
-					{
-						$this->directory = '';
-						return explode('/', $this->routes['404_override'], 2);
-					}
-					else
-					{
-						show_404($this->directory.$segments[0]);
-					}
-				}
-			}
-			else
-			{
-				// Is the method being specified in the route?
-				$segments = explode('/', $this->default_controller);
-				if ( ! file_exists(APPPATH.'controllers/'.$this->directory.$segments[0].'.php'))
-				{
-					$this->directory = '';
-				}
-			}
+		$this->set_class($class);
+		$this->set_method($method);
 
-			return $segments;
-		}
+		// Assign routed segments, index starting from 1
+		$this->uri->rsegments = array(
+			1 => $class,
+			2 => $method
+		);
 
-		// If we've gotten this far it means that the URI does not correlate to a valid
-		// controller class. We will now see if there is an override
-		if ( ! empty($this->routes['404_override']))
+		log_message('debug', 'No URI present. Default controller set.');
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Validate request
+	 *
+	 * Attempts validate the URI request and determine the controller path.
+	 *
+	 * @used-by	CI_Router::_set_request()
+	 * @param	array	$segments	URI segments
+	 * @return	mixed	URI segments
+	 */
+	protected function _validate_request($segments)
+	{
+		$c = count($segments);
+		// Loop through our segments and return as soon as a controller
+		// is found or when such a directory doesn't exist
+		while ($c-- > 0)
 		{
-			if (sscanf($this->routes['404_override'], '%[^/]/%s', $class, $method) !== 2)
+			$test = $this->directory
+				.ucfirst($this->translate_uri_dashes === TRUE ? str_replace('-', '_', $segments[0]) : $segments[0]);
+
+			if ( ! file_exists(APPPATH.'controllers/'.$test.'.php') && is_dir(APPPATH.'controllers/'.$this->directory.$segments[0]))
 			{
-				$method = 'index';
+				$this->set_directory(array_shift($segments), TRUE);
+				continue;
 			}
 
-			return array($class, $method);
+			return $segments;
 		}
 
-		// Nothing else to do at this point but show a 404
-		show_404($segments[0]);
+		// This means that all segments were actually directories
+		return $segments;
 	}
 
 	// --------------------------------------------------------------------
@@ -347,16 +353,43 @@ class CI_Router {
 		// Turn the segment array into a URI string
 		$uri = implode('/', $this->uri->segments);
 
+		// Get HTTP verb
+		$http_verb = isset($_SERVER['REQUEST_METHOD']) ? strtolower($_SERVER['REQUEST_METHOD']) : 'cli';
+
 		// Is there a literal match?  If so we're done
-		if (isset($this->routes[$uri]) && is_string($this->routes[$uri]))
+		if (isset($this->routes[$uri]))
 		{
-			return $this->_set_request(explode('/', $this->routes[$uri]));
+			// Check default routes format
+			if (is_string($this->routes[$uri]))
+			{
+				$this->_set_request(explode('/', $this->routes[$uri]));
+				return;
+			}
+			// Is there a matching http verb?
+			elseif (is_array($this->routes[$uri]) && isset($this->routes[$uri][$http_verb]))
+			{
+				$this->_set_request(explode('/', $this->routes[$uri][$http_verb]));
+				return;
+			}
 		}
 
-		// Loop through the route array looking for wild-cards
+		// Loop through the route array looking for wildcards
 		foreach ($this->routes as $key => $val)
 		{
-			// Convert wild-cards to RegEx
+			// Check if route format is using http verb
+			if (is_array($val))
+			{
+				if (isset($val[$http_verb]))
+				{
+					$val = $val[$http_verb];
+				}
+				else
+				{
+					continue;
+				}
+			}
+
+			// Convert wildcards to RegEx
 			$key = str_replace(array(':any', ':num'), array('[^/]+', '[0-9]+'), $key);
 
 			// Does the RegEx match?
@@ -406,13 +439,14 @@ class CI_Router {
 					$val = preg_replace('#^'.$key.'$#', $val, $uri);
 				}
 
-				return $this->_set_request(explode('/', $val));
+				$this->_set_request(explode('/', $val));
+				return;
 			}
 		}
 
 		// If we got this far it means we didn't encounter a
 		// matching route so we'll set the site default route
-		$this->_set_request($this->uri->segments);
+		$this->_set_request(array_values($this->uri->segments));
 	}
 
 	// --------------------------------------------------------------------
@@ -473,11 +507,19 @@ class CI_Router {
 	 * Set directory name
 	 *
 	 * @param	string	$dir	Directory name
+	 * @param	bool	$appent	Whether we're appending rather then setting the full value
 	 * @return	void
 	 */
-	public function set_directory($dir)
+	public function set_directory($dir, $append = FALSE)
 	{
-		$this->directory = str_replace(array('/', '.'), '', $dir).'/';
+		if ($append !== TRUE OR empty($this->directory))
+		{
+			$this->directory = str_replace('.', '', trim($dir, '/')).'/';
+		}
+		else
+		{
+			$this->directory .= str_replace('.', '', trim($dir, '/')).'/';
+		}
 	}
 
 	// --------------------------------------------------------------------
@@ -496,38 +538,6 @@ class CI_Router {
 		return $this->directory;
 	}
 
-	// --------------------------------------------------------------------
-
-	/**
-	 * Set controller overrides
-	 *
-	 * @param	array	$routing	Route overrides
-	 * @return	void
-	 */
-	public function _set_overrides($routing)
-	{
-		if ( ! is_array($routing))
-		{
-			return;
-		}
-
-		if (isset($routing['directory']))
-		{
-			$this->set_directory($routing['directory']);
-		}
-
-		if ( ! empty($routing['controller']))
-		{
-			$this->set_class($routing['controller']);
-		}
-
-		if (isset($routing['function']))
-		{
-			$routing['function'] = empty($routing['function']) ? 'index' : $routing['function'];
-			$this->set_method($routing['function']);
-		}
-	}
-
 }
 
 /* End of file Router.php */
diff --git a/system/core/Security.php b/system/core/Security.php
index 196d61144..95957a3d8 100644
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -38,6 +38,30 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 class CI_Security {
 
 	/**
+	 * List of sanitize filename strings
+	 *
+	 * @var	array
+	 */
+	public $filename_bad_chars =	array(
+		'../', '<!--', '-->', '<', '>',
+		"'", '"', '&', '$', '#',
+		'{', '}', '[', ']', '=',
+		';', '?', '%20', '%22',
+		'%3c',		// <
+		'%253c',	// <
+		'%3e',		// >
+		'%0e',		// >
+		'%28',		// (
+		'%29',		// )
+		'%2528',	// (
+		'%26',		// &
+		'%24',		// $
+		'%3f',		// ?
+		'%3b',		// ;
+		'%3d'		// =
+	);
+
+	/**
 	 * XSS Hash
 	 *
 	 * Random Hash for protecting URLs.
@@ -93,7 +117,6 @@ class CI_Security {
 		'document.write'	=> '[removed]',
 		'.parentNode'		=> '[removed]',
 		'.innerHTML'		=> '[removed]',
-		'window.location'	=> '[removed]',
 		'-moz-binding'		=> '[removed]',
 		'<!--'				=> '&lt;!--',
 		'-->'				=> '--&gt;',
@@ -108,6 +131,7 @@ class CI_Security {
 	 */
 	protected $_never_allowed_regex = array(
 		'javascript\s*:',
+		'(document|(document\.)?window)\.(location|on\w*)',
 		'expression\s*(\(|&\#40;)', // CSS and IE
 		'vbscript\s*:', // IE, surprise!
 		'Redirect\s+302',
@@ -527,13 +551,13 @@ class CI_Security {
 
 		do
 		{
-			$matches = $matches1 = 0;
+			$m1 = $m2 = 0;
 
+			$str = preg_replace('/(&#x0*[0-9a-f]{2,5})(?![0-9a-f;])/iS', '$1;', $str, -1, $m1);
+			$str = preg_replace('/(&#\d{2,4})(?![0-9;])/S', '$1;', $str, -1, $m2);
 			$str = html_entity_decode($str, ENT_COMPAT, $charset);
-			$str = preg_replace('~&#x(0*[0-9a-f]{2,5})~ei', 'chr(hexdec("\\1"))', $str, -1, $matches);
-			$str = preg_replace('~&#([0-9]{2,4})~e', 'chr(\\1)', $str, -1, $matches1);
 		}
-		while ($matches OR $matches1);
+		while ($m1 OR $m2);
 
 		return $str;
 	}
@@ -549,24 +573,7 @@ class CI_Security {
 	 */
 	public function sanitize_filename($str, $relative_path = FALSE)
 	{
-		$bad = array(
-			'../', '<!--', '-->', '<', '>',
-			"'", '"', '&', '$', '#',
-			'{', '}', '[', ']', '=',
-			';', '?', '%20', '%22',
-			'%3c',		// <
-			'%253c',	// <
-			'%3e',		// >
-			'%0e',		// >
-			'%28',		// (
-			'%29',		// )
-			'%2528',	// (
-			'%26',		// &
-			'%24',		// $
-			'%3f',		// ?
-			'%3b',		// ;
-			'%3d'		// =
-		);
+		$bad = $this->filename_bad_chars;
 
 		if ( ! $relative_path)
 		{
@@ -596,7 +603,7 @@ class CI_Security {
 	 */
 	public function strip_image_tags($str)
 	{
-		return preg_replace(array('#<img\s+.*?src\s*=\s*["\'](.+?)["\'].*?\>#', '#<img\s+.*?src\s*=\s*(.+?).*?\>#'), '\\1', $str);
+		return preg_replace(array('#<img[\s/]+.*?src\s*=\s*["\'](.+?)["\'].*?\>#', '#<img[\s/]+.*?src\s*=\s*(.+?).*?\>#'), '\\1', $str);
 	}
 
 	// ----------------------------------------------------------------
@@ -641,8 +648,8 @@ class CI_Security {
 	 */
 	protected function _remove_evil_attributes($str, $is_image)
 	{
-		// All javascript event handlers (e.g. onload, onclick, onmouseover), style, and xmlns
-		$evil_attributes = array('on\w*', 'style', 'xmlns', 'formaction');
+		// Formaction, style, and xmlns
+		$evil_attributes = array('style', 'xmlns', 'formaction');
 
 		if ($is_image === TRUE)
 		{
@@ -830,14 +837,15 @@ class CI_Security {
 		 * Add a semicolon if missing.  We do this to enable
 		 * the conversion of entities to ASCII later.
 		 */
-		$str = preg_replace('#(&\#?[0-9a-z]{2,})([\x00-\x20])*;?#i', '\\1;\\2', $str);
+		$str = preg_replace('/(&#\d{2,4})(?![0-9;])/', '$1;', $str);
+		$str = preg_replace('/(&[a-z]{2,})(?![a-z;])/i', '$1;', $str);
 
 		/*
 		 * Validate UTF16 two byte encoding (x00)
 		 *
 		 * Just as above, adds a semicolon if missing.
 		 */
-		$str = preg_replace('#(&\#x?)([0-9A-F]+);?#i', '\\1\\2;', $str);
+		$str = preg_replace('/(&#x0*[0-9a-f]{2,5})(?![0-9a-f;])/i', '$1;', $str);
 
 		/*
 		 * Un-Protect GET variables in URLs
@@ -877,7 +885,7 @@ class CI_Security {
 	{
 		if ($this->_csrf_hash === '')
 		{
-			// If the cookie exists we will use it's value.
+			// If the cookie exists we will use its value.
 			// We don't necessarily want to regenerate it with
 			// each page load since a page could contain embedded
 			// sub-pages causing this feature to fail
@@ -887,7 +895,7 @@ class CI_Security {
 				return $this->_csrf_hash = $_COOKIE[$this->_csrf_cookie_name];
 			}
 
-			$this->_csrf_hash = md5(uniqid(rand(), TRUE));
+			$this->_csrf_hash = md5(uniqid(mt_rand(), TRUE));
 			$this->csrf_set_cookie();
 		}
 
diff --git a/system/core/URI.php b/system/core/URI.php
index bc086d223..13682cbee 100644
--- a/system/core/URI.php
+++ b/system/core/URI.php
@@ -44,21 +44,21 @@ class CI_URI {
 	 *
 	 * @var	array
 	 */
-	public $keyval =	array();
+	public $keyval = array();
 
 	/**
 	 * Current URI string
 	 *
 	 * @var	string
 	 */
-	public $uri_string;
+	public $uri_string = '';
 
 	/**
 	 * List of URI segments
 	 *
 	 * @var	array
 	 */
-	public $segments =	array();
+	public $segments = array();
 
 	/**
 	 * Re-indexed list of URI segments
@@ -67,90 +67,67 @@ class CI_URI {
 	 *
 	 * @var	array
 	 */
-	public $rsegments =	array();
+	public $rsegments = array();
 
 	/**
-	 * Class constructor
+	 * Permitted URI chars
 	 *
-	 * Simply globalizes the $RTR object. The front
-	 * loads the Router class early on so it's not available
-	 * normally as other classes are.
+	 * PCRE character group allowed in URI segments
 	 *
-	 * @return	void
+	 * @var	string
 	 */
-	public function __construct()
-	{
-		$this->config =& load_class('Config', 'core');
-		log_message('debug', 'URI Class Initialized');
-	}
-
-	// --------------------------------------------------------------------
+	protected $_permitted_uri_chars;
 
 	/**
-	 * Fetch URI String
+	 * Class constructor
 	 *
-	 * @used-by	CI_Router
 	 * @return	void
 	 */
-	public function _fetch_uri_string()
+	public function __construct()
 	{
-		$protocol = strtoupper($this->config->item('uri_protocol'));
+		$this->config =& load_class('Config', 'core');
 
-		if ($protocol === 'AUTO')
+		// If query strings are enabled, we don't need to parse any segments.
+		// However, they don't make sense under CLI.
+		if (is_cli() OR $this->config->item('enable_query_strings') !== TRUE)
 		{
-			// Is the request coming from the command line?
-			if ($this->_is_cli_request())
+			$this->_permitted_uri_chars = $this->config->item('permitted_uri_chars');
+
+			// If it's a CLI request, ignore the configuration
+			if (is_cli() OR ($protocol = strtoupper($this->config->item('uri_protocol'))) === 'CLI')
 			{
 				$this->_set_uri_string($this->_parse_argv());
-				return;
 			}
-
-			// Is there a PATH_INFO variable? This should be the easiest solution.
-			if (isset($_SERVER['PATH_INFO']))
+			elseif ($protocol === 'AUTO')
 			{
-				$this->_set_uri_string($_SERVER['PATH_INFO']);
-				return;
+				// Is there a PATH_INFO variable? This should be the easiest solution.
+				if (isset($_SERVER['PATH_INFO']))
+				{
+					$this->_set_uri_string($_SERVER['PATH_INFO']);
+				}
+				// No PATH_INFO? Let's try REQUST_URI or QUERY_STRING then
+				elseif (($uri = $this->_parse_request_uri()) !== '' OR ($uri = $this->_parse_query_string()) !== '')
+				{
+					$this->_set_uri_string($uri);
+				}
+				// As a last ditch effor, let's try using the $_GET array
+				elseif (is_array($_GET) && count($_GET) === 1 && trim(key($_GET), '/') !== '')
+				{
+					$this->_set_uri_string(key($_GET));
+				}
 			}
-
-			// Let's try REQUEST_URI then, this will work in most situations
-			if (($uri = $this->_parse_request_uri()) !== '')
+			elseif (method_exists($this, ($method = '_parse_'.strtolower($protocol))))
 			{
-				$this->_set_uri_string($uri);
-				return;
+				$this->_set_uri_string($this->$method());
 			}
-
-			// No REQUEST_URI either?... What about QUERY_STRING?
-			if (($uri = $this->_parse_query_string()) !== '')
+			else
 			{
+				$uri = isset($_SERVER[$protocol]) ? $_SERVER[$protocol] : @getenv($protocol);
 				$this->_set_uri_string($uri);
-				return;
-			}
-
-			// As a last ditch effort let's try using the $_GET array
-			if (is_array($_GET) && count($_GET) === 1 && trim(key($_GET), '/') !== '')
-			{
-				$this->_set_uri_string(key($_GET));
-				return;
 			}
-
-			// We've exhausted all our options...
-			$this->uri_string = '';
-			return;
 		}
 
-		if ($protocol === 'CLI')
-		{
-			$this->_set_uri_string($this->_parse_argv());
-			return;
-		}
-		elseif (method_exists($this, ($method = '_parse_'.strtolower($protocol))))
-		{
-			$this->_set_uri_string($this->$method());
-			return;
-		}
-
-		$uri = isset($_SERVER[$protocol]) ? $_SERVER[$protocol] : @getenv($protocol);
-		$this->_set_uri_string($uri);
+		log_message('debug', 'URI Class Initialized');
 	}
 
 	// --------------------------------------------------------------------
@@ -165,6 +142,35 @@ class CI_URI {
 	{
 		// Filter out control characters and trim slashes
 		$this->uri_string = trim(remove_invisible_characters($str, FALSE), '/');
+
+		if ($this->uri_string !== '')
+		{
+			// Remove the URL suffix, if present
+			if (($suffix = (string) $this->config->item('url_suffix')) !== '')
+			{
+				$slen = strlen($suffix);
+
+				if (substr($this->uri_string, -$slen) === $suffix)
+				{
+					$this->uri_string = substr($this->uri_string, 0, -$slen);
+				}
+			}
+
+			$this->segments[0] = NULL;
+			// Populate the segments array
+			foreach (explode('/', preg_replace('|/*(.+?)/*$|', '\\1', $this->uri_string)) as $val)
+			{
+				// Filter segments for security
+				$val = trim($this->filter_uri($val));
+
+				if ($val !== '')
+				{
+					$this->segments[] = $val;
+				}
+			}
+
+			unset($this->segments[0]);
+		}
 	}
 
 	// --------------------------------------------------------------------
@@ -225,36 +231,10 @@ class CI_URI {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Remove relative directory (../) and multi slashes (///)
-	 *
-	 * Do some final cleaning of the URI and return it, currently only used in self::_parse_request_uri()
-	 *
-	 * @param	string	$url
-	 * @return	string
-	 */
-	protected function _remove_relative_directory($uri)
-	{
-		$uris = array();
-		$tok = strtok($uri, '/');
-		while ($tok !== FALSE)
-		{
-			if (( ! empty($tok) OR $tok === '0') && $tok !== '..')
-			{
-				$uris[] = $tok;
-			}
-			$tok = strtok('/');
-		}
-		return implode('/', $uris);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Parse QUERY_STRING
 	 *
 	 * Will parse QUERY_STRING and automatically detect the URI from it.
 	 *
-	 * @used-by	CI_URI::_fetch_uri_string()
 	 * @return	string
 	 */
 	protected function _parse_query_string()
@@ -280,23 +260,6 @@ class CI_URI {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Is CLI Request?
-	 *
-	 * Duplicate of method from the Input class to test to see if
-	 * a request was made from the command line.
-	 *
-	 * @see		CI_Input::is_cli_request()
-	 * @used-by	CI_URI::_fetch_uri_string()
-	 * @return 	bool
-	 */
-	protected function _is_cli_request()
-	{
-		return (PHP_SAPI === 'cli') OR defined('STDIN');
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Parse CLI arguments
 	 *
 	 * Take each command line argument and assume it is a URI segment.
@@ -312,104 +275,52 @@ class CI_URI {
 	// --------------------------------------------------------------------
 
 	/**
-	 * Filter URI
+	 * Remove relative directory (../) and multi slashes (///)
 	 *
-	 * Filters segments for malicious characters.
+	 * Do some final cleaning of the URI and return it, currently only used in self::_parse_request_uri()
 	 *
-	 * @used-by	CI_Router
-	 * @param	string	$str
+	 * @param	string	$url
 	 * @return	string
 	 */
-	public function _filter_uri($str)
+	protected function _remove_relative_directory($uri)
 	{
-		if ($str !== '' && $this->config->item('permitted_uri_chars') != '' && $this->config->item('enable_query_strings') === FALSE)
+		$uris = array();
+		$tok = strtok($uri, '/');
+		while ($tok !== FALSE)
 		{
-			// preg_quote() in PHP 5.3 escapes -, so the str_replace() and addition of - to preg_quote() is to maintain backwards
-			// compatibility as many are unaware of how characters in the permitted_uri_chars will be parsed as a regex pattern
-			if ( ! preg_match('|^['.str_replace(array('\\-', '\-'), '-', preg_quote($this->config->item('permitted_uri_chars'), '-')).']+$|i', $str))
+			if (( ! empty($tok) OR $tok === '0') && $tok !== '..')
 			{
-				show_error('The URI you submitted has disallowed characters.', 400);
+				$uris[] = $tok;
 			}
+			$tok = strtok('/');
 		}
 
-		// Convert programatic characters to entities and return
-		return str_replace(
-					array('$',     '(',     ')',     '%28',   '%29'), // Bad
-					array('&#36;', '&#40;', '&#41;', '&#40;', '&#41;'), // Good
-					$str);
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
-	 * Remove URL suffix
-	 *
-	 * Removes the suffix from the URL if needed.
-	 *
-	 * @used-by	CI_Router
-	 * @return	void
-	 */
-	public function _remove_url_suffix()
-	{
-		$suffix = (string) $this->config->item('url_suffix');
-
-		if ($suffix === '')
-		{
-			return;
-		}
-
-		$slen = strlen($suffix);
-
-		if (substr($this->uri_string, -$slen) === $suffix)
-		{
-			$this->uri_string = substr($this->uri_string, 0, -$slen);
-		}
+		return implode('/', $uris);
 	}
 
 	// --------------------------------------------------------------------
 
 	/**
-	 * Explode URI segments
+	 * Filter URI
 	 *
-	 * The individual segments will be stored in the $this->segments array.
+	 * Filters segments for malicious characters.
 	 *
-	 * @see		CI_URI::$segments
-	 * @used-by	CI_Router
-	 * @return	void
+	 * @param	string	$str
+	 * @return	string
 	 */
-	public function _explode_segments()
+	public function filter_uri($str)
 	{
-		foreach (explode('/', preg_replace('|/*(.+?)/*$|', '\\1', $this->uri_string)) as $val)
+		if ( ! empty($str) && ! empty($this->_permitted_uri_chars) && ! preg_match('/^['.$this->_permitted_uri_chars.']+$/i'.(UTF8_ENABLED ? 'u' : ''), $str))
 		{
-			// Filter segments for security
-			$val = trim($this->_filter_uri($val));
-
-			if ($val !== '')
-			{
-				$this->segments[] = $val;
-			}
+			show_error('The URI you submitted has disallowed characters.', 400);
 		}
-	}
 
-	// --------------------------------------------------------------------
-
-	/**
-	 * Re-index Segments
-	 *
-	 * Re-indexes the CI_URI::$segment array so that it starts at 1 rather
-	 * than 0. Doing so makes it simpler to use methods like
-	 * CI_URI::segment(n) since there is a 1:1 relationship between the
-	 * segment array and the actual segments.
-	 *
-	 * @used-by	CI_Router
-	 * @return	void
-	 */
-	public function _reindex_segments()
-	{
-		array_unshift($this->segments, NULL);
-		array_unshift($this->rsegments, NULL);
-		unset($this->segments[0]);
-		unset($this->rsegments[0]);
+		// Convert programatic characters to entities and return
+		return str_replace(
+			array('$',     '(',     ')',     '%28',   '%29'),	// Bad
+			array('&#36;', '&#40;', '&#41;', '&#40;', '&#41;'),	// Good
+			$str
+		);
 	}
 
 	// --------------------------------------------------------------------
@@ -720,12 +631,7 @@ class CI_URI {
 	{
 		global $RTR;
 
-		if (($dir = $RTR->directory) === '/')
-		{
-			$dir = '';
-		}
-
-		return $dir.implode('/', $this->rsegment_array());
+		return ltrim($RTR->directory, '/').implode('/', $this->rsegments);
 	}
 
 }
diff --git a/system/core/Utf8.php b/system/core/Utf8.php
index a78616d40..828a8aeba 100644
--- a/system/core/Utf8.php
+++ b/system/core/Utf8.php
@@ -66,7 +66,7 @@ class CI_Utf8 {
 		}
 
 		if (
-			@preg_match('/./u', 'é') === 1	// PCRE must support UTF-8
+			defined('PREG_BAD_UTF8_ERROR')	// PCRE must support UTF-8
 			&& function_exists('iconv')	// iconv must be installed
 			&& MB_ENABLED === TRUE		// mbstring must be enabled
 			&& $charset === 'UTF-8'		// Application charset must be UTF-8