Merge branch '3.1-stable' into develop

Conflicts resolved:
	system/core/CodeIgniter.php
	system/core/Common.php
	system/core/Input.php
	system/helpers/cookie_helper.php
	tests/codeigniter/helpers/html_helper_test.php
	user_guide_src/source/changelog.rst
	user_guide_src/source/conf.py
	user_guide_src/source/installation/downloads.rst
	user_guide_src/source/installation/upgrading.rst
	user_guide_src/source/libraries/input.rst

31 files changed, 172 insertions, 127 deletions

diff --git a/system/core/Common.php b/system/core/Common.php
index cef9f47e0..c4f6dd30b 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -318,12 +318,9 @@ if ( ! function_exists('get_mimes'))
 
 		if (empty($_mimes))
 		{
-			$_mimes = array();
-
-			if (file_exists(APPPATH.'config/mimes.php'))
-			{
-				$_mimes = array_merge($_mimes, include(APPPATH.'config/mimes.php'));
-			}
+			$_mimes = file_exists(APPPATH.'config/mimes.php')
+				? include(APPPATH.'config/mimes.php')
+				: array();
 
 			if (file_exists(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
 			{
@@ -564,12 +561,12 @@ if ( ! function_exists('set_status_header'))
 		if (strpos(PHP_SAPI, 'cgi') === 0)
 		{
 			header('Status: '.$code.' '.$text, TRUE);
+			return;
 		}
-		else
-		{
-			$server_protocol = isset($_SERVER['SERVER_PROTOCOL']) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.1';
-			header($server_protocol.' '.$code.' '.$text, TRUE, $code);
-		}
+
+		$server_protocol = (isset($_SERVER['SERVER_PROTOCOL']) && in_array($_SERVER['SERVER_PROTOCOL'], array('HTTP/1.0', 'HTTP/1.1', 'HTTP/2'), TRUE))
+			? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.1';
+		header($server_protocol.' '.$code.' '.$text, TRUE, $code);
 	}
 }
 
diff --git a/system/core/Input.php b/system/core/Input.php
index 70a3c61ee..dcaae60eb 100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -304,7 +304,7 @@ 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 = 0, $domain = '', $path = '/', $prefix = '', $secure = FALSE, $httponly = FALSE)
+	public function set_cookie($name, $value = '', $expire = 0, $domain = '', $path = '/', $prefix = '', $secure = NULL, $httponly = NULL)
 	{
 		if (is_array($name))
 		{
@@ -333,15 +333,13 @@ class CI_Input {
 			$path = config_item('cookie_path');
 		}
 
-		if ($secure === FALSE && config_item('cookie_secure') === TRUE)
-		{
-			$secure = config_item('cookie_secure');
-		}
+		$secure = ($secure === NULL && config_item('cookie_secure') !== NULL)
+			? (bool) config_item('cookie_secure')
+			: (bool) $secure;
 
-		if ($httponly === FALSE && config_item('cookie_httponly') !== FALSE)
-		{
-			$httponly = config_item('cookie_httponly');
-		}
+		$httponly = ($httponly === NULL && config_item('cookie_httponly') !== NULL)
+			? (bool) config_item('cookie_httponly')
+			: (bool) $httponly;
 
 		if ( ! is_numeric($expire) OR $expire < 0)
 		{
diff --git a/system/core/Log.php b/system/core/Log.php
index 67b315b6b..dd6ab8b90 100644
--- a/system/core/Log.php
+++ b/system/core/Log.php
@@ -105,11 +105,11 @@ class CI_Log {
 	protected $_levels = array('ERROR' => 1, 'DEBUG' => 2, 'INFO' => 3, 'ALL' => 4);
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	// --------------------------------------------------------------------
 
@@ -122,7 +122,7 @@ class CI_Log {
 	{
 		$config =& get_config();
 
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 
 		$this->_log_path = ($config['log_path'] !== '')
 			? rtrim($config['log_path'], '/\\').DIRECTORY_SEPARATOR : APPPATH.'logs'.DIRECTORY_SEPARATOR;
@@ -266,7 +266,7 @@ class CI_Log {
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
@@ -283,7 +283,7 @@ class CI_Log {
 	 */
 	protected static function substr($str, $start, $length = NULL)
 	{
-		if (self::$func_override)
+		if (self::$func_overload)
 		{
 			return mb_substr($str, $start, $length, '8bit');
 		}
diff --git a/system/core/Output.php b/system/core/Output.php
index 2cdb9808c..c684c94c9 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -123,11 +123,11 @@ class CI_Output {
 	public $parse_exec_vars = TRUE;
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	/**
 	 * Class constructor
@@ -145,7 +145,7 @@ class CI_Output {
 			&& extension_loaded('zlib')
 		);
 
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 
 		// Get mime types for later
 		$this->mimes =& get_mimes();
@@ -817,7 +817,7 @@ class CI_Output {
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
@@ -834,7 +834,7 @@ class CI_Output {
 	 */
 	protected static function substr($str, $start, $length = NULL)
 	{
-		if (self::$func_override)
+		if (self::$func_overload)
 		{
 			return mb_substr($str, $start, $length, '8bit');
 		}
diff --git a/system/core/Security.php b/system/core/Security.php
index 4ad550fff..4b6df01a3 100644
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -355,9 +355,9 @@ class CI_Security {
 		// Is the string an array?
 		if (is_array($str))
 		{
-			while (list($key) = each($str))
+			foreach ($str as $key => &$value)
 			{
-				$str[$key] = $this->xss_clean($str[$key]);
+				$str[$key] = $this->xss_clean($value);
 			}
 
 			return $str;
diff --git a/system/core/compat/hash.php b/system/core/compat/hash.php
index c0eab4909..fc319028d 100644
--- a/system/core/compat/hash.php
+++ b/system/core/compat/hash.php
@@ -173,7 +173,9 @@ if ( ! function_exists('hash_pbkdf2'))
 			return FALSE;
 		}
 
-		$hash_length = strlen(hash($algo, NULL, TRUE));
+		$hash_length = defined('MB_OVERLOAD_STRING')
+			? mb_strlen(hash($algo, NULL, TRUE), '8bit')
+			: strlen(hash($algo, NULL, TRUE));
 		empty($length) && $length = $hash_length;
 
 		// Pre-hash password inputs longer than the algorithm's block size
@@ -219,14 +221,14 @@ if ( ! function_exists('hash_pbkdf2'))
 			'whirlpool' => 64
 		);
 
-		if (isset($block_sizes[$algo]) && strlen($password) > $block_sizes[$algo])
+		if (isset($block_sizes[$algo], $password[$block_sizes[$algo]]))
 		{
 			$password = hash($algo, $password, TRUE);
 		}
 
 		$hash = '';
 		// Note: Blocks are NOT 0-indexed
-		for ($bc = ceil($length / $hash_length), $bi = 1; $bi <= $bc; $bi++)
+		for ($bc = (int) ceil($length / $hash_length), $bi = 1; $bi <= $bc; $bi++)
 		{
 			$key = $derived_key = hash_hmac($algo, $salt.pack('N', $bi), $password, TRUE);
 			for ($i = 1; $i < $iterations; $i++)
@@ -238,6 +240,13 @@ if ( ! function_exists('hash_pbkdf2'))
 		}
 
 		// This is not RFC-compatible, but we're aiming for natural PHP compatibility
-		return substr($raw_output ? $hash : bin2hex($hash), 0, $length);
+		if ( ! $raw_output)
+		{
+			$hash = bin2hex($hash);
+		}
+
+		return defined('MB_OVERLOAD_STRING')
+			? mb_substr($hash, 0, $length, '8bit')
+			: substr($hash, 0, $length);
 	}
 }
diff --git a/system/core/compat/password.php b/system/core/compat/password.php
index 84be66738..fa28f5492 100644
--- a/system/core/compat/password.php
+++ b/system/core/compat/password.php
@@ -94,8 +94,8 @@ if ( ! function_exists('password_hash'))
 	 */
 	function password_hash($password, $algo, array $options = array())
 	{
-		static $func_override;
-		isset($func_override) OR $func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		static $func_overload;
+		isset($func_overload) OR $func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 
 		if ($algo !== 1)
 		{
@@ -109,7 +109,7 @@ if ( ! function_exists('password_hash'))
 			return NULL;
 		}
 
-		if (isset($options['salt']) && ($saltlen = ($func_override ? mb_strlen($options['salt'], '8bit') : strlen($options['salt']))) < 22)
+		if (isset($options['salt']) && ($saltlen = ($func_overload ? mb_strlen($options['salt'], '8bit') : strlen($options['salt']))) < 22)
 		{
 			trigger_error('password_hash(): Provided salt is too short: '.$saltlen.' expecting 22', E_USER_WARNING);
 			return NULL;
@@ -144,7 +144,7 @@ if ( ! function_exists('password_hash'))
 				stream_set_chunk_size($fp, 16);
 
 				$options['salt'] = '';
-				for ($read = 0; $read < 16; $read = ($func_override) ? mb_strlen($options['salt'], '8bit') : strlen($options['salt']))
+				for ($read = 0; $read < 16; $read = ($func_overload) ? mb_strlen($options['salt'], '8bit') : strlen($options['salt']))
 				{
 					if (($read = fread($fp, 16 - $read)) === FALSE)
 					{
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 1daee99a8..ef375227c 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -2576,26 +2576,27 @@ abstract class CI_DB_query_builder extends CI_DB_driver {
 	 */
 	protected function _compile_order_by()
 	{
-		if (is_array($this->qb_orderby) && count($this->qb_orderby) > 0)
+		if (empty($this->qb_orderby))
 		{
-			for ($i = 0, $c = count($this->qb_orderby); $i < $c; $i++)
+			return '';
+		}
+
+		for ($i = 0, $c = count($this->qb_orderby); $i < $c; $i++)
+		{
+			if (is_string($this->qb_orderby[$i]))
 			{
-				if ($this->qb_orderby[$i]['escape'] !== FALSE && ! $this->_is_literal($this->qb_orderby[$i]['field']))
-				{
-					$this->qb_orderby[$i]['field'] = $this->protect_identifiers($this->qb_orderby[$i]['field']);
-				}
+				continue;
+			}
 
-				$this->qb_orderby[$i] = $this->qb_orderby[$i]['field'].$this->qb_orderby[$i]['direction'];
+			if ($this->qb_orderby[$i]['escape'] !== FALSE && ! $this->_is_literal($this->qb_orderby[$i]['field']))
+			{
+				$this->qb_orderby[$i]['field'] = $this->protect_identifiers($this->qb_orderby[$i]['field']);
 			}
 
-			return $this->qb_orderby = "\nORDER BY ".implode(', ', $this->qb_orderby);
-		}
-		elseif (is_string($this->qb_orderby))
-		{
-			return $this->qb_orderby;
+			$this->qb_orderby[$i] = $this->qb_orderby[$i]['field'].$this->qb_orderby[$i]['direction'];
 		}
 
-		return '';
+		return "\nORDER BY ".implode(', ', $this->qb_orderby);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/ibase/ibase_driver.php b/system/database/drivers/ibase/ibase_driver.php
index fea3bfe52..3069d6699 100644
--- a/system/database/drivers/ibase/ibase_driver.php
+++ b/system/database/drivers/ibase/ibase_driver.php
@@ -395,7 +395,7 @@ class CI_DB_ibase_driver extends CI_DB {
 	 */
 	protected function _insert_batch($table, $keys, $values)
 	{
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mssql/mssql_driver.php b/system/database/drivers/mssql/mssql_driver.php
index a490d206c..e91a817b6 100644
--- a/system/database/drivers/mssql/mssql_driver.php
+++ b/system/database/drivers/mssql/mssql_driver.php
@@ -488,7 +488,7 @@ class CI_DB_mssql_driver extends CI_DB {
 			return parent::_insert_batch($table, $keys, $values);
 		}
 
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index 290101153..a7ef648d7 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -210,7 +210,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 				$this->_mysqli->close();
 				$message = 'MySQLi was configured for an SSL connection, but got an unencrypted connection instead!';
 				log_message('error', $message);
-				return ($this->db->db_debug) ? $this->db->display_error($message, '', TRUE) : FALSE;
+				return ($this->db_debug) ? $this->display_error($message, '', TRUE) : FALSE;
 			}
 
 			if ( ! $this->_mysqli->set_charset($this->char_set))
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index ed44412c1..ef982fc63 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -316,7 +316,7 @@ class CI_DB_odbc_driver extends CI_DB_driver {
 	 */
 	protected function _escape_str($str)
 	{
-		$this->db->display_error('db_unsupported_feature');
+		$this->display_error('db_unsupported_feature');
 	}
 
 	// --------------------------------------------------------------------
@@ -340,7 +340,7 @@ class CI_DB_odbc_driver extends CI_DB_driver {
 	 */
 	public function insert_id()
 	{
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
index 3249a1d7f..08243232e 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
@@ -331,7 +331,7 @@ class CI_DB_pdo_dblib_driver extends CI_DB_pdo_driver {
 			return parent::_insert_batch($table, $keys, $values);
 		}
 
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 }
diff --git a/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
index aa5e7d6e7..cb93f19b7 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_firebird_driver.php
@@ -274,6 +274,6 @@ class CI_DB_pdo_firebird_driver extends CI_DB_pdo_driver {
 	 */
 	protected function _insert_batch($table, $keys, $values)
 	{
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 }
diff --git a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
index 66c15dac6..64b13d827 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
@@ -182,7 +182,7 @@ class CI_DB_pdo_mysql_driver extends CI_DB_pdo_driver {
 		{
 			$message = 'PDO_MYSQL was configured for an SSL connection, but got an unencrypted connection instead!';
 			log_message('error', $message);
-			return ($this->db->db_debug) ? $this->db->display_error($message, '', TRUE) : FALSE;
+			return ($this->db_debug) ? $this->display_error($message, '', TRUE) : FALSE;
 		}
 
 		return $pdo;
diff --git a/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php b/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php
index 5a492d881..066dd9614 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_odbc_driver.php
@@ -168,7 +168,7 @@ class CI_DB_pdo_odbc_driver extends CI_DB_pdo_driver {
 	 */
 	protected function _escape_str($str)
 	{
-		$this->db->display_error('db_unsupported_feature');
+		$this->display_error('db_unsupported_feature');
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
index 1cf6c614d..07c429eec 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
@@ -363,7 +363,7 @@ class CI_DB_pdo_sqlsrv_driver extends CI_DB_pdo_driver {
 			return parent::_insert_batch($table, $keys, $values);
 		}
 
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 }
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 75b1d4c37..505d609b8 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -130,9 +130,9 @@ class CI_DB_postgre_driver extends CI_DB {
 		 */
 		foreach (array('connect_timeout', 'options', 'sslmode', 'service') as $key)
 		{
-			if (isset($this->$key) && is_string($this->key) && $this->key !== '')
+			if (isset($this->$key) && is_string($this->$key) && $this->$key !== '')
 			{
-				$this->dsn .= $key."='".$this->key."' ";
+				$this->dsn .= $key."='".$this->$key."' ";
 			}
 		}
 
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index e4f403180..a43e2539a 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -525,7 +525,7 @@ class CI_DB_sqlsrv_driver extends CI_DB {
 			return parent::_insert_batch($table, $keys, $values);
 		}
 
-		return ($this->db->db_debug) ? $this->db->display_error('db_unsupported_feature') : FALSE;
+		return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : FALSE;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/helpers/cookie_helper.php b/system/helpers/cookie_helper.php
index d069cdb15..a1a9324ff 100644
--- a/system/helpers/cookie_helper.php
+++ b/system/helpers/cookie_helper.php
@@ -67,7 +67,7 @@ if ( ! function_exists('set_cookie'))
 	 * @param	bool	true makes the cookie accessible via http(s) only (no javascript)
 	 * @return	void
 	 */
-	function set_cookie($name, $value = '', $expire = 0, $domain = '', $path = '/', $prefix = '', $secure = FALSE, $httponly = FALSE)
+	function set_cookie($name, $value = '', $expire = 0, $domain = '', $path = '/', $prefix = '', $secure = NULL, $httponly = NULL)
 	{
 		// Set the config file options
 		get_instance()->input->set_cookie($name, $value, $expire, $domain, $path, $prefix, $secure, $httponly);
diff --git a/system/helpers/html_helper.php b/system/helpers/html_helper.php
index b5e8ed783..93ba2dd7d 100644
--- a/system/helpers/html_helper.php
+++ b/system/helpers/html_helper.php
@@ -192,7 +192,7 @@ if ( ! function_exists('img'))
 
 		foreach ($src as $k => $v)
 		{
-			if ($k === 'src' && ! preg_match('#^([a-z]+:)?//#i', $v))
+			if ($k === 'src' && ! preg_match('#^(data:[a-z,;])|(([a-z]+:)?(?<!data:)//)#i', $v))
 			{
 				if ($index_page === TRUE)
 				{
diff --git a/system/helpers/string_helper.php b/system/helpers/string_helper.php
index 311f7a420..896973704 100644
--- a/system/helpers/string_helper.php
+++ b/system/helpers/string_helper.php
@@ -168,9 +168,7 @@ if ( ! function_exists('reduce_multiples'))
 if ( ! function_exists('random_string'))
 {
 	/**
-	 * Create a Random String
-	 *
-	 * Useful for generating passwords or hashes.
+	 * Create a "Random" String
 	 *
 	 * @param	string	type of random string.  basic, alpha, alnum, numeric, nozero, unique, md5, encrypt and sha1
 	 * @param	int	number of characters
diff --git a/system/helpers/text_helper.php b/system/helpers/text_helper.php
index 07c01c3af..217729b70 100644
--- a/system/helpers/text_helper.php
+++ b/system/helpers/text_helper.php
@@ -138,7 +138,10 @@ if ( ! function_exists('ascii_to_entities'))
 	function ascii_to_entities($str)
 	{
 		$out = '';
-		for ($i = 0, $s = strlen($str) - 1, $count = 1, $temp = array(); $i <= $s; $i++)
+		$length = defined('MB_OVERLOAD_STRING')
+			? mb_strlen($str, '8bit') - 1
+			: strlen($str) - 1;
+		for ($i = 0, $count = 1, $temp = array(); $i <= $length; $i++)
 		{
 			$ordinal = ord($str[$i]);
 
@@ -176,7 +179,7 @@ if ( ! function_exists('ascii_to_entities'))
 					$temp = array();
 				}
 				// If this is the last iteration, just output whatever we have
-				elseif ($i === $s)
+				elseif ($i === $length)
 				{
 					$out .= '&#'.implode(';', $temp).';';
 				}
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index 1483f2203..d7178f321 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -368,11 +368,11 @@ class CI_Email {
 	);
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	// --------------------------------------------------------------------
 
@@ -389,7 +389,7 @@ class CI_Email {
 		$this->charset = config_item('charset');
 		$this->initialize($config);
 
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 
 		log_message('info', 'Email Class Initialized');
 	}
@@ -2420,7 +2420,7 @@ class CI_Email {
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
@@ -2437,7 +2437,7 @@ class CI_Email {
 	 */
 	protected static function substr($str, $start, $length = NULL)
 	{
-		if (self::$func_override)
+		if (self::$func_overload)
 		{
 			return mb_substr($str, $start, $length, '8bit');
 		}
diff --git a/system/libraries/Encrypt.php b/system/libraries/Encrypt.php
index 46f374726..ebcc6e8c6 100644
--- a/system/libraries/Encrypt.php
+++ b/system/libraries/Encrypt.php
@@ -122,7 +122,7 @@ class CI_Encrypt {
 
 			$key = config_item('encryption_key');
 
-			if ( ! strlen($key))
+			if ( ! self::strlen($key))
 			{
 				show_error('In order to use the encryption class requires that you set an encryption key in your config file.');
 			}
@@ -252,7 +252,7 @@ class CI_Encrypt {
 		$string = $this->_xor_merge($string, $key);
 
 		$dec = '';
-		for ($i = 0, $l = strlen($string); $i < $l; $i++)
+		for ($i = 0, $l = self::strlen($string); $i < $l; $i++)
 		{
 			$dec .= ($string[$i++] ^ $string[$i]);
 		}
@@ -275,7 +275,8 @@ class CI_Encrypt {
 	{
 		$hash = $this->hash($key);
 		$str = '';
-		for ($i = 0, $ls = strlen($string), $lh = strlen($hash); $i < $ls; $i++)
+
+		for ($i = 0, $ls = self::strlen($string), $lh = self::strlen($hash); $i < $ls; $i++)
 		{
 			$str .= $string[$i] ^ $hash[($i % $lh)];
 		}
@@ -295,7 +296,7 @@ class CI_Encrypt {
 	public function mcrypt_encode($data, $key)
 	{
 		$init_size = mcrypt_get_iv_size($this->_get_cipher(), $this->_get_mode());
-		$init_vect = mcrypt_create_iv($init_size, MCRYPT_RAND);
+		$init_vect = mcrypt_create_iv($init_size, MCRYPT_DEV_URANDOM);
 		return $this->_add_cipher_noise($init_vect.mcrypt_encrypt($this->_get_cipher(), $key, $data, $this->_get_mode(), $init_vect), $key);
 	}
 
@@ -313,13 +314,14 @@ class CI_Encrypt {
 		$data = $this->_remove_cipher_noise($data, $key);
 		$init_size = mcrypt_get_iv_size($this->_get_cipher(), $this->_get_mode());
 
-		if ($init_size > strlen($data))
+		if ($init_size > self::strlen($data))
 		{
 			return FALSE;
 		}
 
-		$init_vect = substr($data, 0, $init_size);
-		$data = substr($data, $init_size);
+		$init_vect = self::substr($data, 0, $init_size);
+		$data      = self::substr($data, $init_size);
+
 		return rtrim(mcrypt_decrypt($this->_get_cipher(), $key, $data, $this->_get_mode(), $init_vect), "\0");
 	}
 
@@ -339,7 +341,7 @@ class CI_Encrypt {
 		$key = $this->hash($key);
 		$str = '';
 
-		for ($i = 0, $j = 0, $ld = strlen($data), $lk = strlen($key); $i < $ld; ++$i, ++$j)
+		for ($i = 0, $j = 0, $ld = self::strlen($data), $lk = self::strlen($key); $i < $ld; ++$i, ++$j)
 		{
 			if ($j >= $lk)
 			{
@@ -369,7 +371,7 @@ class CI_Encrypt {
 		$key = $this->hash($key);
 		$str = '';
 
-		for ($i = 0, $j = 0, $ld = strlen($data), $lk = strlen($key); $i < $ld; ++$i, ++$j)
+		for ($i = 0, $j = 0, $ld = self::strlen($data), $lk = self::strlen($key); $i < $ld; ++$i, ++$j)
 		{
 			if ($j >= $lk)
 			{
@@ -477,4 +479,43 @@ class CI_Encrypt {
 		return hash($this->_hash_type, $str);
 	}
 
+	// --------------------------------------------------------------------
+
+	/**
+	 * Byte-safe strlen()
+	 *
+	 * @param	string	$str
+	 * @return	int
+	 */
+	protected static function strlen($str)
+	{
+		return defined('MB_OVERLOAD_STRING')
+			? mb_strlen($str, '8bit')
+			: strlen($str);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Byte-safe substr()
+	 *
+	 * @param	string	$str
+	 * @param	int	$start
+	 * @param	int	$length
+	 * @return	string
+	 */
+	protected static function substr($str, $start, $length = NULL)
+	{
+		if (defined('MB_OVERLOAD_STRING'))
+		{
+			// mb_substr($str, $start, null, '8bit') returns an empty
+			// string on PHP 5.3
+			isset($length) OR $length = ($start >= 0 ? self::strlen($str) - $start : -$start);
+			return mb_substr($str, $start, $length, '8bit');
+		}
+
+		return isset($length)
+			? substr($str, $start, $length)
+			: substr($str, $start);
+	}
 }
diff --git a/system/libraries/Encryption.php b/system/libraries/Encryption.php
index 6799d0fef..c3ddf60ed 100644
--- a/system/libraries/Encryption.php
+++ b/system/libraries/Encryption.php
@@ -135,11 +135,11 @@ class CI_Encryption {
 	);
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	// --------------------------------------------------------------------
 
@@ -161,7 +161,7 @@ class CI_Encryption {
 			show_error('Encryption: Unable to find an available encryption driver.');
 		}
 
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 		$this->initialize($params);
 
 		if ( ! isset($this->_key) && self::strlen($key = config_item('encryption_key')) > 0)
@@ -911,7 +911,7 @@ class CI_Encryption {
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
@@ -928,7 +928,7 @@ class CI_Encryption {
 	 */
 	protected static function substr($str, $start, $length = NULL)
 	{
-		if (self::$func_override)
+		if (self::$func_overload)
 		{
 			return mb_substr($str, $start, $length, '8bit');
 		}
diff --git a/system/libraries/Session/drivers/Session_database_driver.php b/system/libraries/Session/drivers/Session_database_driver.php
index 31f5a4663..b519b782f 100644
--- a/system/libraries/Session/drivers/Session_database_driver.php
+++ b/system/libraries/Session/drivers/Session_database_driver.php
@@ -208,12 +208,8 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		// Prevent previous QB calls from messing with our queries
 		$this->_db->reset_query();
 
-		if ($this->_lock === FALSE)
-		{
-			return $this->_fail();
-		}
 		// Was the ID regenerated?
-		elseif ($session_id !== $this->_session_id)
+		if (isset($this->_session_id) && $session_id !== $this->_session_id)
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
@@ -223,6 +219,10 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 			$this->_row_exists = FALSE;
 			$this->_session_id = $session_id;
 		}
+		elseif ($this->_lock === FALSE)
+		{
+			return $this->_fail();
+		}
 
 		if ($this->_row_exists === FALSE)
 		{
diff --git a/system/libraries/Session/drivers/Session_files_driver.php b/system/libraries/Session/drivers/Session_files_driver.php
index 6016e094e..8860ef667 100644
--- a/system/libraries/Session/drivers/Session_files_driver.php
+++ b/system/libraries/Session/drivers/Session_files_driver.php
@@ -84,11 +84,11 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 	protected $_sid_regexp;
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	// ------------------------------------------------------------------------
 
@@ -115,7 +115,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 
 		$this->_sid_regexp = $this->_config['_sid_regexp'];
 
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 	}
 
 	// ------------------------------------------------------------------------
@@ -399,7 +399,7 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
diff --git a/system/libraries/Xmlrpc.php b/system/libraries/Xmlrpc.php
index e025c4508..ca35e85c0 100644
--- a/system/libraries/Xmlrpc.php
+++ b/system/libraries/Xmlrpc.php
@@ -460,7 +460,7 @@ class CI_Xmlrpc {
 			{
 				if (is_array($value[0]) && ($value[1] === 'struct' OR $value[1] === 'array'))
 				{
-					while (list($k) = each($value[0]))
+					foreach (array_keys($value[0]) as $k)
 					{
 						$value[0][$k] = $this->values_parsing($value[0][$k]);
 					}
@@ -929,15 +929,15 @@ class XML_RPC_Response
 
 		if (is_array($array))
 		{
-			while (list($key) = each($array))
+			foreach ($array as $key => &$value)
 			{
-				if (is_array($array[$key]))
+				if (is_array($value))
 				{
-					$array[$key] = $this->decode($array[$key]);
+					$array[$key] = $this->decode($value);
 				}
 				elseif ($this->xss_clean)
 				{
-					$array[$key] = $CI->security->xss_clean($array[$key]);
+					$array[$key] = $CI->security->xss_clean($value);
 				}
 			}
 
@@ -991,10 +991,11 @@ class XML_RPC_Response
 			reset($xmlrpc_val->me['struct']);
 			$arr = array();
 
-			while (list($key,$value) = each($xmlrpc_val->me['struct']))
+			foreach ($xmlrpc_val->me['struct'] as $key => &$value)
 			{
 				$arr[$key] = $this->xmlrpc_decoder($value);
 			}
+
 			return $arr;
 		}
 	}
@@ -1560,17 +1561,17 @@ class XML_RPC_Message extends CI_Xmlrpc
 
 		if ( ! empty($array))
 		{
-			while (list($key) = each($array))
+			foreach ($array as $key => &$value)
 			{
-				if (is_array($array[$key]))
+				if (is_array($value))
 				{
-					$array[$key] = $this->output_parameters($array[$key]);
+					$array[$key] = $this->output_parameters($value);
 				}
 				elseif ($key !== 'bits' && $this->xss_clean)
 				{
 					// 'bits' is for the MetaWeblog API image bits
 					// @todo - this needs to be made more general purpose
-					$array[$key] = $CI->security->xss_clean($array[$key]);
+					$array[$key] = $CI->security->xss_clean($value);
 				}
 			}
 
@@ -1630,7 +1631,7 @@ class XML_RPC_Message extends CI_Xmlrpc
 			reset($param->me['struct']);
 			$arr = array();
 
-			while (list($key,$value) = each($param->me['struct']))
+			foreach ($param->me['struct'] as $key => &$value)
 			{
 				$arr[$key] = $this->decode_message($value);
 			}
@@ -1821,7 +1822,7 @@ class XML_RPC_Values extends CI_Xmlrpc
 				// struct
 				$rs .= "<struct>\n";
 				reset($val);
-				while (list($key2, $val2) = each($val))
+				foreach ($val as $key2 => &$val2)
 				{
 					$rs .= "<member>\n<name>{$key2}</name>\n".$this->serializeval($val2)."</member>\n";
 				}
@@ -1882,11 +1883,9 @@ class XML_RPC_Values extends CI_Xmlrpc
 	 */
 	public function serializeval($o)
 	{
-		$ar = $o->me;
-		reset($ar);
-
-		list($typ, $val) = each($ar);
-		return "<value>\n".$this->serializedata($typ, $val)."</value>\n";
+		$array = $o->me;
+		list($value, $type) = array(reset($ar), key($array));
+		return "<value>\n".$this->serializedata($type, $value)."</value>\n";
 	}
 
 	// --------------------------------------------------------------------
@@ -1898,8 +1897,7 @@ class XML_RPC_Values extends CI_Xmlrpc
 	 */
 	public function scalarval()
 	{
-		reset($this->me);
-		return current($this->me);
+		return reset($this->me);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Xmlrpcs.php b/system/libraries/Xmlrpcs.php
index 21de937c8..0274f13b6 100644
--- a/system/libraries/Xmlrpcs.php
+++ b/system/libraries/Xmlrpcs.php
@@ -584,7 +584,7 @@ class CI_Xmlrpcs extends CI_Xmlrpc {
 			return $this->multicall_error('nomethod');
 		}
 
-		list($scalar_type, $scalar_value) = each($methName->me);
+		list($scalar_value, $scalar_type) = array(reset($methName->me), key($methName->me));
 		$scalar_type = $scalar_type === $this->xmlrpcI4 ? $this->xmlrpcInt : $scalar_type;
 
 		if ($methName->kindOf() !== 'scalar' OR $scalar_type !== 'string')
@@ -604,7 +604,7 @@ class CI_Xmlrpcs extends CI_Xmlrpc {
 			return $this->multicall_error('notarray');
 		}
 
-		list($a, $b) = each($params->me);
+		list($b, $a) = array(reset($params->me), key($params->me));
 
 		$msg = new XML_RPC_Message($scalar_value);
 		for ($i = 0, $numParams = count($b); $i < $numParams; $i++)
diff --git a/system/libraries/Zip.php b/system/libraries/Zip.php
index d6974b13a..c14de00c4 100644
--- a/system/libraries/Zip.php
+++ b/system/libraries/Zip.php
@@ -106,11 +106,11 @@ class CI_Zip {
 	public $compression_level = 2;
 
 	/**
-	 * mbstring.func_override flag
+	 * mbstring.func_overload flag
 	 *
 	 * @var	bool
 	 */
-	protected static $func_override;
+	protected static $func_overload;
 
 	/**
 	 * Initialize zip compression class
@@ -119,7 +119,7 @@ class CI_Zip {
 	 */
 	public function __construct()
 	{
-		isset(self::$func_override) OR self::$func_override = (extension_loaded('mbstring') && ini_get('mbstring.func_override'));
+		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));
 
 		$this->now = time();
 		log_message('info', 'Zip Compression Class Initialized');
@@ -500,7 +500,7 @@ class CI_Zip {
 	 */
 	protected static function strlen($str)
 	{
-		return (self::$func_override)
+		return (self::$func_overload)
 			? mb_strlen($str, '8bit')
 			: strlen($str);
 	}
@@ -517,7 +517,7 @@ class CI_Zip {
 	 */
 	protected static function substr($str, $start, $length = NULL)
 	{
-		if (self::$func_override)
+		if (self::$func_overload)
 		{
 			return mb_substr($str, $start, $length, '8bit');
 		}