Merge tag '3.1.11' of git://github.com/bcit-ci/CodeIgniter into dev

Signed-off-by: Florian Pritz <bluewind@xinu.at>

26 files changed, 206 insertions, 143 deletions

diff --git a/application/config/foreign_chars.php b/application/config/foreign_chars.php
index 995f48304..0231f3592 100644
--- a/application/config/foreign_chars.php
+++ b/application/config/foreign_chars.php
@@ -22,10 +22,10 @@ $foreign_characters = array(
 	'/б/' => 'b',
 	'/Ç|Ć|Ĉ|Ċ|Č/' => 'C',
 	'/ç|ć|ĉ|ċ|č/' => 'c',
-	'/Д/' => 'D',
-	'/д/' => 'd',
-	'/Ð|Ď|Đ|Δ/' => 'Dj',
-	'/ð|ď|đ|δ/' => 'dj',
+	'/Д|Δ/' => 'D',
+	'/д|δ/' => 'd',
+	'/Ð|Ď|Đ/' => 'Dj',
+	'/ð|ď|đ/' => 'dj',
 	'/È|É|Ê|Ë|Ē|Ĕ|Ė|Ę|Ě|Ε|Έ|Ẽ|Ẻ|Ẹ|Ề|Ế|Ễ|Ể|Ệ|Е|Э/' => 'E',
 	'/è|é|ê|ë|ē|ĕ|ė|ę|ě|έ|ε|ẽ|ẻ|ẹ|ề|ế|ễ|ể|ệ|е|э/' => 'e',
 	'/Ф/' => 'F',
@@ -38,6 +38,8 @@ $foreign_characters = array(
 	'/ì|í|î|ï|ĩ|ī|ĭ|ǐ|į|ı|η|ή|ί|ι|ϊ|ỉ|ị|и|ы|ї/' => 'i',
 	'/Ĵ/' => 'J',
 	'/ĵ/' => 'j',
+	'/Θ/' => 'TH',
+	'/θ/' => 'th',
 	'/Ķ|Κ|К/' => 'K',
 	'/ķ|κ|к/' => 'k',
 	'/Ĺ|Ļ|Ľ|Ŀ|Ł|Λ|Л/' => 'L',
@@ -54,8 +56,8 @@ $foreign_characters = array(
 	'/ŕ|ŗ|ř|ρ|р/' => 'r',
 	'/Ś|Ŝ|Ş|Ș|Š|Σ|С/' => 'S',
 	'/ś|ŝ|ş|ș|š|ſ|σ|ς|с/' => 's',
-	'/Ț|Ţ|Ť|Ŧ|τ|Т/' => 'T',
-	'/ț|ţ|ť|ŧ|т/' => 't',
+	'/Ț|Ţ|Ť|Ŧ|Τ|Т/' => 'T',
+	'/ț|ţ|ť|ŧ|τ|т/' => 't',
 	'/Þ|þ/' => 'th',
 	'/Ù|Ú|Û|Ũ|Ū|Ŭ|Ů|Ű|Ų|Ư|Ǔ|Ǖ|Ǘ|Ǚ|Ǜ|Ũ|Ủ|Ụ|Ừ|Ứ|Ữ|Ử|Ự|У/' => 'U',
 	'/ù|ú|û|ũ|ū|ŭ|ů|ű|ų|ư|ǔ|ǖ|ǘ|ǚ|ǜ|υ|ύ|ϋ|ủ|ụ|ừ|ứ|ữ|ử|ự|у/' => 'u',
@@ -65,6 +67,10 @@ $foreign_characters = array(
 	'/в/' => 'v',
 	'/Ŵ/' => 'W',
 	'/ŵ/' => 'w',
+	'/Φ/' => 'F',
+	'/φ/' => 'f',
+	'/Χ/' => 'CH',
+	'/χ/' => 'ch',
 	'/Ź|Ż|Ž|Ζ|З/' => 'Z',
 	'/ź|ż|ž|ζ|з/' => 'z',
 	'/Æ|Ǽ/' => 'AE',
@@ -73,10 +79,15 @@ $foreign_characters = array(
 	'/ij/' => 'ij',
 	'/Œ/' => 'OE',
 	'/ƒ/' => 'f',
+	'/Ξ/' => 'KS',
 	'/ξ/' => 'ks',
+	'/Π/' => 'P',
 	'/π/' => 'p',
+	'/Β/' => 'V',
 	'/β/' => 'v',
+	'/Μ/' => 'M',
 	'/μ/' => 'm',
+	'/Ψ/' => 'PS',
 	'/ψ/' => 'ps',
 	'/Ё/' => 'Yo',
 	'/ё/' => 'yo',
diff --git a/application/config/mimes.php b/application/config/mimes.php
index 0ec9db0a0..7aa5c9e4e 100644
--- a/application/config/mimes.php
+++ b/application/config/mimes.php
@@ -140,7 +140,7 @@ return array(
 	'f4v'   =>	array('video/mp4', 'video/x-f4v'),
 	'flv'	=>	'video/x-flv',
 	'webm'	=>	'video/webm',
-	'aac'   =>	'audio/x-acc',
+	'aac'   =>	array('audio/x-aac', 'audio/aac'),
 	'm4u'   =>	'application/vnd.mpegurl',
 	'm3u'   =>	'text/plain',
 	'xspf'  =>	'application/xspf+xml',
diff --git a/application/config/user_agents.php b/application/config/user_agents.php
index ad0b0fd20..c1581e5cd 100644
--- a/application/config/user_agents.php
+++ b/application/config/user_agents.php
@@ -151,6 +151,7 @@ $mobiles = array(
 	'wii'			=> 'Nintendo Wii',
 	'open web'		=> 'Open Web',
 	'openweb'		=> 'OpenWeb',
+	'meizu'                 => 'Meizu',
 
 	// Operating Systems
 	'android'		=> 'Android',
diff --git a/contributing.md b/contributing.md
index 8edb510cf..703fe8f44 100644
--- a/contributing.md
+++ b/contributing.md
@@ -1,6 +1,5 @@
 # Contributing to CodeIgniter
 
-
 CodeIgniter is a community driven project and accepts contributions of code and documentation from the community. These contributions are made in the form of Issues or [Pull Requests](http://help.github.com/send-pull-requests/) on the [CodeIgniter repository](https://github.com/bcit-ci/CodeIgniter) on GitHub.
 
 Issues are a quick way to point out a bug. If you find a bug or documentation error in CodeIgniter then please check a few things first:
@@ -59,7 +58,6 @@ If you are using [Tower](http://www.git-tower.com/) there is a "Sign-Off" checkb
 
 By signing your work in this manner, you certify to a "Developer's Certificate of Origin". The current version of this certificate is in the `DCO.txt` file in the root of this repository.
 
-
 ## How-to Guide
 
 There are two ways to make changes, the easy way and the hard way. Either way you will need to [create a GitHub account](https://github.com/signup/free).
@@ -68,15 +66,15 @@ Easy way GitHub allows in-line editing of files for making simple typo changes a
 
 Hard way The best way to contribute is to "clone" your fork of CodeIgniter to your development area. That sounds like some jargon, but "forking" on GitHub means "making a copy of that repo to your account" and "cloning" means "copying that code to your environment so you can work on it".
 
-1. Set up Git (Windows, Mac & Linux)
-2. Go to the CodeIgniter repo
-3. Fork it
-4. Clone your CodeIgniter repo: git@github.com:<your-name>/CodeIgniter.git
-5. Checkout the "develop" branch At this point you are ready to start making changes. 
+1. [Set up Git](https://help.github.com/en/articles/set-up-git) (Windows, Mac & Linux)
+2. Go to the [CodeIgniter repo](https://github.com/bcit-ci/CodeIgniter)
+3. [Fork it](https://help.github.com/en/articles/fork-a-repo)
+4. [Clone](https://help.github.com/en/articles/fetching-a-remote#clone) your forked CodeIgniter repo: git@github.com:<your-name>/CodeIgniter.git.
+5. Checkout the "develop" branch. At this point you are ready to start making changes.
 6. Fix existing bugs on the Issue tracker after taking a look to see nobody else is working on them.
-7. Commit the files
-8. Push your develop branch to your fork
-9. Send a pull request [http://help.github.com/send-pull-requests/](http://help.github.com/send-pull-requests/)
+7. [Commit](https://help.github.com/en/articles/adding-a-file-to-a-repository-using-the-command-line) the files
+8. [Push](https://help.github.com/en/articles/pushing-to-a-remote) your develop branch to your fork
+9. [Send a pull request](https://help.github.com/en/articles/creating-a-pull-request)
 
 The Reactor Engineers will now be alerted about the change and at least one of the team will respond. If your change fails to meet the guidelines it will be bounced, or feedback will be provided to help you improve it.
 
diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index 56826f1a6..8aecc0a27 100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -55,7 +55,7 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  * @var	string
  *
  */
-	const CI_VERSION = '3.1.10';
+	const CI_VERSION = '3.1.11';
 
 /*
  * ------------------------------------------------------
diff --git a/system/core/Controller.php b/system/core/Controller.php
index 2bb157802..e25b8472c 100644
--- a/system/core/Controller.php
+++ b/system/core/Controller.php
@@ -59,6 +59,13 @@ class CI_Controller {
 	private static $instance;
 
 	/**
+	 * CI_Loader
+	 *
+	 * @var	CI_Loader
+	 */
+	public $load;
+
+	/**
 	 * Class constructor
 	 *
 	 * @return	void
diff --git a/system/core/Log.php b/system/core/Log.php
index 4338aa939..f37726e02 100644
--- a/system/core/Log.php
+++ b/system/core/Log.php
@@ -247,11 +247,11 @@ class CI_Log {
 	 * @param	string	$level 	The error level
 	 * @param	string	$date 	Formatted date string
 	 * @param	string	$message 	The log message
-	 * @return	string	Formatted log line with a new line character '\n' at the end
+	 * @return	string	Formatted log line with a new line character at the end
 	 */
 	protected function _format_line($level, $date, $message)
 	{
-		return $level.' - '.$date.' --> '.$message."\n";
+		return $level.' - '.$date.' --> '.$message.PHP_EOL;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/core/Security.php b/system/core/Security.php
index 883968e26..6a81faff1 100644
--- a/system/core/Security.php
+++ b/system/core/Security.php
@@ -228,6 +228,7 @@ class CI_Security {
 
 		// Check CSRF token validity, but don't error on mismatch just yet - we'll want to regenerate
 		$valid = isset($_POST[$this->_csrf_token_name], $_COOKIE[$this->_csrf_cookie_name])
+			&& is_string($_POST[$this->_csrf_token_name]) && is_string($_COOKIE[$this->_csrf_cookie_name])
 			&& hash_equals($_POST[$this->_csrf_token_name], $_COOKIE[$this->_csrf_cookie_name]);
 
 		// We kill this since we're done and we don't want to pollute the _POST array
diff --git a/system/database/DB_result.php b/system/database/DB_result.php
index 0dbac1633..ed5252d49 100644
--- a/system/database/DB_result.php
+++ b/system/database/DB_result.php
@@ -381,7 +381,7 @@ class CI_DB_result {
 	 */
 	public function custom_row_object($n, $type)
 	{
-		isset($this->custom_result_object[$type]) OR $this->custom_result_object($type);
+		isset($this->custom_result_object[$type]) OR $this->custom_result_object[$type] = $this->custom_result_object($type);
 
 		if (count($this->custom_result_object[$type]) === 0)
 		{
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index 78e77bc18..440715ae1 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -383,7 +383,7 @@ class CI_DB_mysql_driver extends CI_DB {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = 'SHOW TABLES FROM '.$this->escape_identifiers($this->database);
+		$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
 
 		if ($prefix_limit !== FALSE && $this->dbprefix !== '')
 		{
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index d374e0174..0ca0f48fc 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -429,7 +429,7 @@ class CI_DB_mysqli_driver extends CI_DB {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = 'SHOW TABLES FROM '.$this->escape_identifiers($this->database);
+		$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
 
 		if ($prefix_limit !== FALSE && $this->dbprefix !== '')
 		{
diff --git a/system/database/drivers/oci8/oci8_forge.php b/system/database/drivers/oci8/oci8_forge.php
index 20217f2b8..58f3c3913 100644
--- a/system/database/drivers/oci8/oci8_forge.php
+++ b/system/database/drivers/oci8/oci8_forge.php
@@ -81,6 +81,13 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 	 */
 	protected $_unsigned		= FALSE;
 
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null		= 'NULL';
+
 	// --------------------------------------------------------------------
 
 	/**
diff --git a/system/database/drivers/pdo/pdo_result.php b/system/database/drivers/pdo/pdo_result.php
index 03c0f9f9d..b3973da46 100644
--- a/system/database/drivers/pdo/pdo_result.php
+++ b/system/database/drivers/pdo/pdo_result.php
@@ -133,7 +133,7 @@ class CI_DB_pdo_result extends CI_DB_result {
 
 				$retval[$i]			= new stdClass();
 				$retval[$i]->name		= $field['name'];
-				$retval[$i]->type		= $field['native_type'];
+				$retval[$i]->type		= isset($field['native_type']) ? $field['native_type'] : null;
 				$retval[$i]->max_length		= ($field['len'] > 0) ? $field['len'] : NULL;
 				$retval[$i]->primary_key	= (int) ( ! empty($field['flags']) && in_array('primary_key', $field['flags'], TRUE));
 			}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php b/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php
index 54752f153..eceb59796 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_firebird_forge.php
@@ -150,7 +150,7 @@ class CI_DB_pdo_firebird_forge extends CI_DB_pdo_forge {
 			if ( ! empty($field[$i]['default']))
 			{
 				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
-					.' SET DEFAULT '.$field[$i]['default'];
+					.' SET '.$field[$i]['default'];
 			}
 
 			if (isset($field[$i]['null']))
diff --git a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
index 26bc30e14..73b88bcfd 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_mysql_driver.php
@@ -279,7 +279,7 @@ class CI_DB_pdo_mysql_driver extends CI_DB_pdo_driver {
 	 */
 	protected function _list_tables($prefix_limit = FALSE)
 	{
-		$sql = 'SHOW TABLES';
+		$sql = 'SHOW TABLES FROM '.$this->_escape_char.$this->database.$this->_escape_char;
 
 		if ($prefix_limit === TRUE && $this->dbprefix !== '')
 		{
diff --git a/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php b/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php
index 0abda5930..b5d3eb143 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_oci_forge.php
@@ -74,6 +74,13 @@ class CI_DB_pdo_oci_forge extends CI_DB_pdo_forge {
 	 */
 	protected $_unsigned		= FALSE;
 
+	/**
+	 * NULL value representation in CREATE/ALTER TABLE statements
+	 *
+	 * @var	string
+	 */
+	protected $_null		= 'NULL';
+
 	// --------------------------------------------------------------------
 
 	/**
diff --git a/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
index b05d473ee..2d0c74b2e 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
@@ -98,7 +98,7 @@ class CI_DB_pdo_pgsql_driver extends CI_DB_pdo_driver {
 
 			if ( ! empty($this->username))
 			{
-				$this->dsn .= ';username='.$this->username;
+				$this->dsn .= ';user='.$this->username;
 				empty($this->password) OR $this->dsn .= ';password='.$this->password;
 			}
 		}
diff --git a/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php b/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php
index ff7a11075..a4ccff407 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_pgsql_forge.php
@@ -130,7 +130,7 @@ class CI_DB_pdo_pgsql_forge extends CI_DB_pdo_forge {
 			if ( ! empty($field[$i]['default']))
 			{
 				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
-					.' SET DEFAULT '.$field[$i]['default'];
+					.' SET '.$field[$i]['default'];
 			}
 
 			if (isset($field[$i]['null']))
diff --git a/system/database/drivers/postgre/postgre_forge.php b/system/database/drivers/postgre/postgre_forge.php
index 353ddac99..481e222b8 100644
--- a/system/database/drivers/postgre/postgre_forge.php
+++ b/system/database/drivers/postgre/postgre_forge.php
@@ -125,7 +125,7 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 			if ( ! empty($field[$i]['default']))
 			{
 				$sqls[] = $sql.' ALTER COLUMN '.$this->db->escape_identifiers($field[$i]['name'])
-					.' SET DEFAULT '.$field[$i]['default'];
+					.' SET '.$field[$i]['default'];
 			}
 
 			if (isset($field[$i]['null']))
diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
index 37596189a..bff96fbfb 100644
--- a/system/libraries/Cache/drivers/Cache_redis.php
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -76,6 +76,13 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	protected $_serialized = array();
 
+	/**
+	 * del()/delete() method name depending on phpRedis version
+	 *
+	 * @var	string
+	 */
+	protected static $_delete_name;
+
 	// ------------------------------------------------------------------------
 
 	/**
@@ -97,6 +104,10 @@ class CI_Cache_redis extends CI_Driver
 			return;
 		}
 
+		isset(static::$_delete_name) OR static::$_delete_name = version_compare(phpversion('phpredis'), '5', '>=')
+			? 'del'
+			: 'delete';
+
 		$CI =& get_instance();
 
 		if ($CI->config->load('redis', TRUE, TRUE))
@@ -135,10 +146,6 @@ class CI_Cache_redis extends CI_Driver
 		{
 			log_message('error', 'Cache: Redis connection refused ('.$e->getMessage().')');
 		}
-
-		// Initialize the index of serialized values.
-		$serialized = $this->_redis->sMembers('_ci_redis_serialized');
-		empty($serialized) OR $this->_serialized = array_flip($serialized);
 	}
 
 	// ------------------------------------------------------------------------
@@ -153,7 +160,7 @@ class CI_Cache_redis extends CI_Driver
 	{
 		$value = $this->_redis->get($key);
 
-		if ($value !== FALSE && isset($this->_serialized[$key]))
+		if ($value !== FALSE && $this->_redis->sIsMember('_ci_redis_serialized', $key))
 		{
 			return unserialize($value);
 		}
@@ -184,9 +191,8 @@ class CI_Cache_redis extends CI_Driver
 			isset($this->_serialized[$id]) OR $this->_serialized[$id] = TRUE;
 			$data = serialize($data);
 		}
-		elseif (isset($this->_serialized[$id]))
+		else
 		{
-			$this->_serialized[$id] = NULL;
 			$this->_redis->sRemove('_ci_redis_serialized', $id);
 		}
 
@@ -203,16 +209,12 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function delete($key)
 	{
-		if ($this->_redis->delete($key) !== 1)
+		if ($this->_redis->{static::$_delete_name}($key) !== 1)
 		{
 			return FALSE;
 		}
 
-		if (isset($this->_serialized[$key]))
-		{
-			$this->_serialized[$key] = NULL;
-			$this->_redis->sRemove('_ci_redis_serialized', $key);
-		}
+		$this->_redis->sRemove('_ci_redis_serialized', $key);
 
 		return TRUE;
 	}
@@ -228,7 +230,7 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function increment($id, $offset = 1)
 	{
-		return $this->_redis->incr($id, $offset);
+		return $this->_redis->incrBy($id, $offset);
 	}
 
 	// ------------------------------------------------------------------------
@@ -242,7 +244,7 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function decrement($id, $offset = 1)
 	{
-		return $this->_redis->decr($id, $offset);
+		return $this->_redis->decrBy($id, $offset);
 	}
 
 	// ------------------------------------------------------------------------
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index 1bd55499a..fdf202010 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -1208,6 +1208,13 @@ class CI_Form_validation {
 			$str = $matches[2];
 		}
 
+		// Apparently, FILTER_VALIDATE_URL doesn't reject digit-only names for some reason ...
+		// See https://github.com/bcit-ci/CodeIgniter/issues/5755
+		if (ctype_digit($str))
+		{
+			return FALSE;
+		}
+
 		// PHP 7 accepts IPv6 addresses within square brackets as hostnames,
 		// but it appears that the PR that came in with https://bugs.php.net/bug.php?id=68039
 		// was never merged into a PHP 5 branch ... https://3v4l.org/8PsSN
diff --git a/system/libraries/Session/Session_driver.php b/system/libraries/Session/Session_driver.php
index 14ebdb09f..dbc833739 100644
--- a/system/libraries/Session/Session_driver.php
+++ b/system/libraries/Session/Session_driver.php
@@ -184,25 +184,4 @@ abstract class CI_Session_driver implements SessionHandlerInterface {
 
 		return TRUE;
 	}
-
-	// ------------------------------------------------------------------------
-
-	/**
-	 * Fail
-	 *
-	 * Drivers other than the 'files' one don't (need to) use the
-	 * session.save_path INI setting, but that leads to confusing
-	 * error messages emitted by PHP when open() or write() fail,
-	 * as the message contains session.save_path ...
-	 * To work around the problem, the drivers will call this method
-	 * so that the INI is set just in time for the error message to
-	 * be properly generated.
-	 *
-	 * @return	mixed
-	 */
-	protected function _fail()
-	{
-		ini_set('session.save_path', config_item('sess_save_path'));
-		return $this->_failure;
-	}
 }
diff --git a/system/libraries/Session/drivers/Session_database_driver.php b/system/libraries/Session/drivers/Session_database_driver.php
index 734fe624f..89afe3455 100644
--- a/system/libraries/Session/drivers/Session_database_driver.php
+++ b/system/libraries/Session/drivers/Session_database_driver.php
@@ -130,7 +130,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	{
 		if (empty($this->_db->conn_id) && ! $this->_db->db_connect())
 		{
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		$this->php5_validate_id();
@@ -150,48 +150,47 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	 */
 	public function read($session_id)
 	{
-		if ($this->_get_lock($session_id) !== FALSE)
+		if ($this->_get_lock($session_id) === FALSE)
 		{
-			// Prevent previous QB calls from messing with our queries
-			$this->_db->reset_query();
-
-			// Needed by write() to detect session_regenerate_id() calls
-			$this->_session_id = $session_id;
+			return $this->_failure;
+		}
 
-			$this->_db
-				->select('data')
-				->from($this->_config['save_path'])
-				->where('id', $session_id);
+		// Prevent previous QB calls from messing with our queries
+		$this->_db->reset_query();
 
-			if ($this->_config['match_ip'])
-			{
-				$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
-			}
+		// Needed by write() to detect session_regenerate_id() calls
+		$this->_session_id = $session_id;
 
-			if ( ! ($result = $this->_db->get()) OR ($result = $result->row()) === NULL)
-			{
-				// PHP7 will reuse the same SessionHandler object after
-				// ID regeneration, so we need to explicitly set this to
-				// FALSE instead of relying on the default ...
-				$this->_row_exists = FALSE;
-				$this->_fingerprint = md5('');
-				return '';
-			}
+		$this->_db
+			->select('data')
+			->from($this->_config['save_path'])
+			->where('id', $session_id);
 
-			// PostgreSQL's variant of a BLOB datatype is Bytea, which is a
-			// PITA to work with, so we use base64-encoded data in a TEXT
-			// field instead.
-			$result = ($this->_platform === 'postgre')
-				? base64_decode(rtrim($result->data))
-				: $result->data;
+		if ($this->_config['match_ip'])
+		{
+			$this->_db->where('ip_address', $_SERVER['REMOTE_ADDR']);
+		}
 
-			$this->_fingerprint = md5($result);
-			$this->_row_exists = TRUE;
-			return $result;
+		if ( ! ($result = $this->_db->get()) OR ($result = $result->row()) === NULL)
+		{
+			// PHP7 will reuse the same SessionHandler object after
+			// ID regeneration, so we need to explicitly set this to
+			// FALSE instead of relying on the default ...
+			$this->_row_exists = FALSE;
+			$this->_fingerprint = md5('');
+			return '';
 		}
 
-		$this->_fingerprint = md5('');
-		return '';
+		// PostgreSQL's variant of a BLOB datatype is Bytea, which is a
+		// PITA to work with, so we use base64-encoded data in a TEXT
+		// field instead.
+		$result = ($this->_platform === 'postgre')
+			? base64_decode(rtrim($result->data))
+			: $result->data;
+
+		$this->_fingerprint = md5($result);
+		$this->_row_exists = TRUE;
+		return $result;
 	}
 
 	// ------------------------------------------------------------------------
@@ -215,7 +214,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return $this->_fail();
+				return $this->_failure;
 			}
 
 			$this->_row_exists = FALSE;
@@ -223,7 +222,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 		}
 		elseif ($this->_lock === FALSE)
 		{
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		if ($this->_row_exists === FALSE)
@@ -242,7 +241,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 				return $this->_success;
 			}
 
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		$this->_db->where('id', $session_id);
@@ -265,7 +264,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -280,7 +279,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 	public function close()
 	{
 		return ($this->_lock && ! $this->_release_lock())
-			? $this->_fail()
+			? $this->_failure
 			: $this->_success;
 	}
 
@@ -309,7 +308,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 
 			if ( ! $this->_db->delete($this->_config['save_path']))
 			{
-				return $this->_fail();
+				return $this->_failure;
 			}
 		}
 
@@ -319,7 +318,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -339,7 +338,7 @@ class CI_Session_database_driver extends CI_Session_driver implements SessionHan
 
 		return ($this->_db->delete($this->_config['save_path'], 'timestamp < '.(time() - $maxlifetime)))
 			? $this->_success
-			: $this->_fail();
+			: $this->_failure;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Session/drivers/Session_files_driver.php b/system/libraries/Session/drivers/Session_files_driver.php
index 467059434..2899b7dec 100644
--- a/system/libraries/Session/drivers/Session_files_driver.php
+++ b/system/libraries/Session/drivers/Session_files_driver.php
@@ -135,12 +135,14 @@ class CI_Session_files_driver extends CI_Session_driver implements SessionHandle
 		{
 			if ( ! mkdir($save_path, 0700, TRUE))
 			{
-				throw new Exception("Session: Configured save path '".$this->_config['save_path']."' is not a directory, doesn't exist or cannot be created.");
+				log_message('error', "Session: Configured save path '".$this->_config['save_path']."' is not a directory, doesn't exist or cannot be created.");
+				return $this->_failure;
 			}
 		}
 		elseif ( ! is_writable($save_path))
 		{
-			throw new Exception("Session: Configured save path '".$this->_config['save_path']."' is not writable by the PHP process.");
+			log_message('error', "Session: Configured save path '".$this->_config['save_path']."' is not writable by the PHP process.");
+			return $this->_failure;
 		}
 
 		$this->_config['save_path'] = $save_path;
diff --git a/system/libraries/Session/drivers/Session_memcached_driver.php b/system/libraries/Session/drivers/Session_memcached_driver.php
index ab54f029f..854adf821 100644
--- a/system/libraries/Session/drivers/Session_memcached_driver.php
+++ b/system/libraries/Session/drivers/Session_memcached_driver.php
@@ -117,7 +117,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		{
 			$this->_memcached = NULL;
 			log_message('error', 'Session: Invalid Memcached save path format: '.$this->_config['save_path']);
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		foreach ($matches as $match)
@@ -142,7 +142,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 		if (empty($server_list))
 		{
 			log_message('error', 'Session: Memcached server pool is empty.');
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		$this->php5_validate_id();
@@ -172,7 +172,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			return $session_data;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -190,14 +190,14 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 	{
 		if ( ! isset($this->_memcached, $this->_lock_key))
 		{
-			return $this->_fail();
+			return $this->_failure;
 		}
 		// Was the ID regenerated?
 		elseif ($session_id !== $this->_session_id)
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return $this->_fail();
+				return $this->_failure;
 			}
 
 			$this->_fingerprint = md5('');
@@ -215,7 +215,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 				return $this->_success;
 			}
 
-			return $this->_fail();
+			return $this->_failure;
 		}
 		elseif (
 			$this->_memcached->touch($key, $this->_config['expiration'])
@@ -225,7 +225,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -244,14 +244,14 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			$this->_release_lock();
 			if ( ! $this->_memcached->quit())
 			{
-				return $this->_fail();
+				return $this->_failure;
 			}
 
 			$this->_memcached = NULL;
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -273,7 +273,7 @@ class CI_Session_memcached_driver extends CI_Session_driver implements SessionHa
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
diff --git a/system/libraries/Session/drivers/Session_redis_driver.php b/system/libraries/Session/drivers/Session_redis_driver.php
index 434b11e58..df38174b4 100644
--- a/system/libraries/Session/drivers/Session_redis_driver.php
+++ b/system/libraries/Session/drivers/Session_redis_driver.php
@@ -76,6 +76,33 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	 */
 	protected $_key_exists = FALSE;
 
+	/**
+	 * Name of setTimeout() method in phpRedis
+	 *
+	 * Due to some deprecated methods in phpRedis, we need to call the
+	 * specific methods depending on the version of phpRedis.
+	 *
+	 * @var string
+	 */
+	protected $_setTimeout_name;
+
+	/**
+	 * Name of delete() method in phpRedis
+	 *
+	 * Due to some deprecated methods in phpRedis, we need to call the
+	 * specific methods depending on the version of phpRedis.
+	 *
+	 * @var string
+	 */
+	protected $_delete_name;
+
+	/**
+	 * Success return value of ping() method in phpRedis
+	 *
+	 * @var mixed
+	 */
+	protected $_ping_success;
+
 	// ------------------------------------------------------------------------
 
 	/**
@@ -88,6 +115,20 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		parent::__construct($params);
 
+		// Detect the names of some methods in phpRedis instance
+		if (version_compare(phpversion('redis'), '5', '>='))
+		{
+			$this->_setTimeout_name = 'expire';
+			$this->_delete_name = 'del';
+			$this->_ping_success = TRUE;
+		}
+		else
+		{
+			$this->_setTimeout_name = 'setTimeout';
+			$this->_delete_name = 'delete';
+			$this->_ping_success = '+PONG';
+		}
+
 		if (empty($this->_config['save_path']))
 		{
 			log_message('error', 'Session: No Redis save path configured.');
@@ -131,7 +172,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if (empty($this->_config['save_path']))
 		{
-			return $this->_fail();
+			return $this->_failure;
 		}
 
 		$redis = new Redis();
@@ -150,12 +191,11 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 		else
 		{
 			$this->_redis = $redis;
+			$this->php5_validate_id();
 			return $this->_success;
 		}
 
-		$this->php5_validate_id();
-
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -185,7 +225,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 			return $session_data;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -203,21 +243,21 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if ( ! isset($this->_redis, $this->_lock_key))
 		{
-			return $this->_fail();
+			return $this->_failure;
 		}
 		// Was the ID regenerated?
 		elseif ($session_id !== $this->_session_id)
 		{
 			if ( ! $this->_release_lock() OR ! $this->_get_lock($session_id))
 			{
-				return $this->_fail();
+				return $this->_failure;
 			}
 
 			$this->_key_exists = FALSE;
 			$this->_session_id = $session_id;
 		}
 
-		$this->_redis->setTimeout($this->_lock_key, 300);
+		$this->_redis->{$this->_setTimeout_name}($this->_lock_key, 300);
 		if ($this->_fingerprint !== ($fingerprint = md5($session_data)) OR $this->_key_exists === FALSE)
 		{
 			if ($this->_redis->set($this->_key_prefix.$session_id, $session_data, $this->_config['expiration']))
@@ -227,12 +267,12 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 				return $this->_success;
 			}
 
-			return $this->_fail();
+			return $this->_failure;
 		}
 
-		return ($this->_redis->setTimeout($this->_key_prefix.$session_id, $this->_config['expiration']))
+		return ($this->_redis->{$this->_setTimeout_name}($this->_key_prefix.$session_id, $this->_config['expiration']))
 			? $this->_success
-			: $this->_fail();
+			: $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -249,12 +289,12 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 		if (isset($this->_redis))
 		{
 			try {
-				if ($this->_redis->ping() === '+PONG')
+				if ($this->_redis->ping() === $this->_ping_success)
 				{
 					$this->_release_lock();
 					if ($this->_redis->close() === FALSE)
 					{
-						return $this->_fail();
+						return $this->_failure;
 					}
 				}
 			}
@@ -284,16 +324,16 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if (isset($this->_redis, $this->_lock_key))
 		{
-			if (($result = $this->_redis->delete($this->_key_prefix.$session_id)) !== 1)
+			if (($result = $this->_redis->{$this->_delete_name}($this->_key_prefix.$session_id)) !== 1)
 			{
-				log_message('debug', 'Session: Redis::delete() expected to return 1, got '.var_export($result, TRUE).' instead.');
+				log_message('debug', 'Session: Redis::'.$this->_delete_name.'() expected to return 1, got '.var_export($result, TRUE).' instead.');
 			}
 
 			$this->_cookie_destroy();
 			return $this->_success;
 		}
 
-		return $this->_fail();
+		return $this->_failure;
 	}
 
 	// ------------------------------------------------------------------------
@@ -345,7 +385,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 		// correct session ID.
 		if ($this->_lock_key === $this->_key_prefix.$session_id.':lock')
 		{
-			return $this->_redis->setTimeout($this->_lock_key, 300);
+			return $this->_redis->{$this->_setTimeout_name}($this->_lock_key, 300);
 		}
 
 		// 30 attempts to obtain a lock, in case another request already has it
@@ -359,11 +399,13 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 				continue;
 			}
 
-			$result = ($ttl === -2)
-				? $this->_redis->set($lock_key, time(), array('nx', 'ex' => 300))
-				: $this->_redis->setex($lock_key, 300, time());
-
-			if ( ! $result)
+			if ($ttl === -2 && ! $this->_redis->set($lock_key, time(), array('nx', 'ex' => 300)))
+			{
+				// Sleep for 1s to wait for lock releases.
+				sleep(1);
+				continue;
+			}
+			elseif ( ! $this->_redis->setex($lock_key, 300, time()))
 			{
 				log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id);
 				return FALSE;
@@ -401,7 +443,7 @@ class CI_Session_redis_driver extends CI_Session_driver implements SessionHandle
 	{
 		if (isset($this->_redis, $this->_lock_key) && $this->_lock)
 		{
-			if ( ! $this->_redis->delete($this->_lock_key))
+			if ( ! $this->_redis->{$this->_delete_name}($this->_lock_key))
 			{
 				log_message('error', 'Session: Error while trying to free lock for '.$this->_lock_key);
 				return FALSE;