Merge branch 'develop' of git://github.com/bcit-ci/CodeIgniter into develop

7 files changed, 190 insertions, 146 deletions

diff --git a/system/libraries/Cache/Cache.php b/system/libraries/Cache/Cache.php
index 0c87a5628..267dffb09 100644
--- a/system/libraries/Cache/Cache.php
+++ b/system/libraries/Cache/Cache.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 2.0.0
  * @filesource
  */
diff --git a/system/libraries/Cache/drivers/Cache_apc.php b/system/libraries/Cache/drivers/Cache_apc.php
index e0d2ffb39..f2b61adb1 100644
--- a/system/libraries/Cache/drivers/Cache_apc.php
+++ b/system/libraries/Cache/drivers/Cache_apc.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 2.0.0
  * @filesource
  */
@@ -49,6 +49,24 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 class CI_Cache_apc extends CI_Driver {
 
 	/**
+	 * Class constructor
+	 *
+	 * Only present so that an error message is logged
+	 * if APC is not available.
+	 *
+	 * @return	void
+	 */
+	public function __construct()
+	{
+		if ( ! $this->is_supported())
+		{
+			log_message('error', 'Cache: Failed to initialize APC; extension not loaded/enabled?');
+		}
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
 	 * Get
 	 *
 	 * Look for a value in the cache. If it exists, return the data
@@ -79,7 +97,7 @@ class CI_Cache_apc extends CI_Driver {
 	 *
 	 * @param	string	$id	Cache ID
 	 * @param	mixed	$data	Data to store
-	 * @param	int	$ttol	Length of time (in seconds) to cache the data
+	 * @param	int	$ttl	Length of time (in seconds) to cache the data
 	 * @param	bool	$raw	Whether to store the raw value
 	 * @return	bool	TRUE on success, FALSE on failure
 	 */
@@ -198,13 +216,6 @@ class CI_Cache_apc extends CI_Driver {
 	 */
 	public function is_supported()
 	{
-		if ( ! extension_loaded('apc') OR ! ini_get('apc.enabled'))
-		{
-			log_message('debug', 'The APC PHP extension must be loaded to use APC Cache.');
-			return FALSE;
-		}
-
-		return TRUE;
+		return (extension_loaded('apc') && ini_get('apc.enabled'));
 	}
-
 }
diff --git a/system/libraries/Cache/drivers/Cache_dummy.php b/system/libraries/Cache/drivers/Cache_dummy.php
index bf80945a9..c6d9a61f1 100644
--- a/system/libraries/Cache/drivers/Cache_dummy.php
+++ b/system/libraries/Cache/drivers/Cache_dummy.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 2.0
  * @filesource
  */
diff --git a/system/libraries/Cache/drivers/Cache_file.php b/system/libraries/Cache/drivers/Cache_file.php
index 68bc1ec96..8a36e9d79 100644
--- a/system/libraries/Cache/drivers/Cache_file.php
+++ b/system/libraries/Cache/drivers/Cache_file.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 2.0
  * @filesource
  */
@@ -120,7 +120,7 @@ class CI_Cache_file extends CI_Driver {
 	 */
 	public function delete($id)
 	{
-		return file_exists($this->_cache_path.$id) ? unlink($this->_cache_path.$id) : FALSE;
+		return is_file($this->_cache_path.$id) ? unlink($this->_cache_path.$id) : FALSE;
 	}
 
 	// ------------------------------------------------------------------------
@@ -216,7 +216,7 @@ class CI_Cache_file extends CI_Driver {
 	 */
 	public function get_metadata($id)
 	{
-		if ( ! file_exists($this->_cache_path.$id))
+		if ( ! is_file($this->_cache_path.$id))
 		{
 			return FALSE;
 		}
@@ -227,13 +227,13 @@ class CI_Cache_file extends CI_Driver {
 		{
 			$mtime = filemtime($this->_cache_path.$id);
 
-			if ( ! isset($data['ttl']))
+			if ( ! isset($data['ttl'], $data['time']))
 			{
 				return FALSE;
 			}
 
 			return array(
-				'expire' => $mtime + $data['ttl'],
+				'expire' => $data['time'] + $data['ttl'],
 				'mtime'	 => $mtime
 			);
 		}
@@ -267,7 +267,7 @@ class CI_Cache_file extends CI_Driver {
 	 */
 	protected function _get($id)
 	{
-		if ( ! file_exists($this->_cache_path.$id))
+		if ( ! is_file($this->_cache_path.$id))
 		{
 			return FALSE;
 		}
diff --git a/system/libraries/Cache/drivers/Cache_memcached.php b/system/libraries/Cache/drivers/Cache_memcached.php
index 111e2109d..4836b6aed 100644
--- a/system/libraries/Cache/drivers/Cache_memcached.php
+++ b/system/libraries/Cache/drivers/Cache_memcached.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 2.0
  * @filesource
  */
@@ -60,7 +60,7 @@ class CI_Cache_memcached extends CI_Driver {
 	 *
 	 * @var array
 	 */
-	protected $_memcache_conf = array(
+	protected $_config = array(
 		'default' => array(
 			'host'		=> '127.0.0.1',
 			'port'		=> 11211,
@@ -81,19 +81,11 @@ class CI_Cache_memcached extends CI_Driver {
 	{
 		// Try to load memcached server info from the config file.
 		$CI =& get_instance();
-		$defaults = $this->_memcache_conf['default'];
+		$defaults = $this->_config['default'];
 
 		if ($CI->config->load('memcached', TRUE, TRUE))
 		{
-			if (is_array($CI->config->config['memcached']))
-			{
-				$this->_memcache_conf = array();
-
-				foreach ($CI->config->config['memcached'] as $name => $conf)
-				{
-					$this->_memcache_conf[$name] = $conf;
-				}
-			}
+			$this->_config = $CI->config->config['memcached'];
 		}
 
 		if (class_exists('Memcached', FALSE))
@@ -106,18 +98,31 @@ class CI_Cache_memcached extends CI_Driver {
 		}
 		else
 		{
-			throw new RuntimeException('Cache: Failed to create Memcache(d) object; extension not loaded?');
+			log_message('error', 'Cache: Failed to create Memcache(d) object; extension not loaded?');
+			return;
 		}
 
-		foreach ($this->_memcache_conf as $cache_server)
+		foreach ($this->_config as $cache_name => $cache_server)
 		{
-			isset($cache_server['hostname']) OR $cache_server['hostname'] = $defaults['host'];
-			isset($cache_server['port']) OR $cache_server['port'] = $defaults['port'];
+			if ( ! isset($cache_server['hostname']))
+			{
+				log_message('debug', 'Cache: Memcache(d) configuration "'.$cache_name.'" doesn\'t include a hostname; ignoring.');
+				continue;
+			}
+			elseif ($cache_server['hostname'][0] === '/')
+			{
+				$cache_server['port'] = 0;
+			}
+			elseif (empty($cache_server['port']))
+			{
+				$cache_server['port'] = $defaults['port'];
+			}
+
 			isset($cache_server['weight']) OR $cache_server['weight'] = $defaults['weight'];
 
-			if (get_class($this->_memcached) === 'Memcache')
+			if ($this->_memcached instanceof Memcache)
 			{
-				// Third parameter is persistance and defaults to TRUE.
+				// Third parameter is persistence and defaults to TRUE.
 				$this->_memcached->addServer(
 					$cache_server['hostname'],
 					$cache_server['port'],
@@ -125,7 +130,7 @@ class CI_Cache_memcached extends CI_Driver {
 					$cache_server['weight']
 				);
 			}
-			else
+			elseif ($this->_memcached instanceof Memcached)
 			{
 				$this->_memcached->addServer(
 					$cache_server['hostname'],
@@ -169,11 +174,11 @@ class CI_Cache_memcached extends CI_Driver {
 			$data = array($data, time(), $ttl);
 		}
 
-		if (get_class($this->_memcached) === 'Memcached')
+		if ($this->_memcached instanceof Memcached)
 		{
 			return $this->_memcached->set($id, $data, $ttl);
 		}
-		elseif (get_class($this->_memcached) === 'Memcache')
+		elseif ($this->_memcached instanceof Memcache)
 		{
 			return $this->_memcached->set($id, $data, 0, $ttl);
 		}
@@ -186,7 +191,7 @@ class CI_Cache_memcached extends CI_Driver {
 	/**
 	 * Delete from Cache
 	 *
-	 * @param	mixed	key to be deleted.
+	 * @param	mixed	$id	key to be deleted.
 	 * @return	bool	true on success, false on failure
 	 */
 	public function delete($id)
@@ -251,7 +256,7 @@ class CI_Cache_memcached extends CI_Driver {
 	/**
 	 * Get Cache Metadata
 	 *
-	 * @param	mixed	key to get cache metadata on
+	 * @param	mixed	$id	key to get cache metadata on
 	 * @return	mixed	FALSE on failure, array on success.
 	 */
 	public function get_metadata($id)
@@ -284,12 +289,27 @@ class CI_Cache_memcached extends CI_Driver {
 	 */
 	public function is_supported()
 	{
-		if ( ! extension_loaded('memcached') && ! extension_loaded('memcache'))
+		return (extension_loaded('memcached') OR extension_loaded('memcache'));
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
+	 * Class destructor
+	 *
+	 * Closes the connection to Memcache(d) if present.
+	 *
+	 * @return	void
+	 */
+	public function __destruct()
+	{
+		if ($this->_memcached instanceof Memcache)
 		{
-			log_message('debug', 'The Memcached Extension must be loaded to use Memcached Cache.');
-			return FALSE;
+			$this->_memcached->close();
+		}
+		elseif ($this->_memcached instanceof Memcached && method_exists($this->_memcached, 'quit'))
+		{
+			$this->_memcached->quit();
 		}
-
-		return TRUE;
 	}
 }
diff --git a/system/libraries/Cache/drivers/Cache_redis.php b/system/libraries/Cache/drivers/Cache_redis.php
index d7dca1973..bb26b3b47 100644
--- a/system/libraries/Cache/drivers/Cache_redis.php
+++ b/system/libraries/Cache/drivers/Cache_redis.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 3.0.0
  * @filesource
  */
@@ -55,11 +55,11 @@ class CI_Cache_redis extends CI_Driver
 	 * @var	array
 	 */
 	protected static $_default_config = array(
-		'socket_type' => 'tcp',
 		'host' => '127.0.0.1',
 		'password' => NULL,
 		'port' => 6379,
-		'timeout' => 0
+		'timeout' => 0,
+		'database' => 0
 	);
 
 	/**
@@ -69,13 +69,6 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	protected $_redis;
 
-	/**
-	 * An internal cache for storing keys of serialized values.
-	 *
-	 * @var	array
-	 */
-	protected $_serialized = array();
-
 	// ------------------------------------------------------------------------
 
 	/**
@@ -91,46 +84,46 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function __construct()
 	{
-		$config = array();
+		if ( ! $this->is_supported())
+		{
+			log_message('error', 'Cache: Failed to create Redis object; extension not loaded?');
+			return;
+		}
+
 		$CI =& get_instance();
 
 		if ($CI->config->load('redis', TRUE, TRUE))
 		{
-			$config = $CI->config->item('redis');
+			$config = array_merge(self::$_default_config, $CI->config->item('redis'));
+		}
+		else
+		{
+			$config = self::$_default_config;
 		}
 
-		$config = array_merge(self::$_default_config, $config);
 		$this->_redis = new Redis();
 
 		try
 		{
-			if ($config['socket_type'] === 'unix')
+			if ( ! $this->_redis->connect($config['host'], ($config['host'][0] === '/' ? 0 : $config['port']), $config['timeout']))
 			{
-				$success = $this->_redis->connect($config['socket']);
+				log_message('error', 'Cache: Redis connection failed. Check your configuration.');
 			}
-			else // tcp socket
+
+			if (isset($config['password']) && ! $this->_redis->auth($config['password']))
 			{
-				$success = $this->_redis->connect($config['host'], $config['port'], $config['timeout']);
+				log_message('error', 'Cache: Redis authentication failed.');
 			}
 
-			if ( ! $success)
+			if (isset($config['database']) && $config['database'] > 0 && ! $this->_redis->select($config['database']))
 			{
-				throw new RuntimeException('Cache: Redis connection failed. Check your configuration.');
+				log_message('error', 'Cache: Redis select database failed.');
 			}
 		}
 		catch (RedisException $e)
 		{
-			throw new RuntimeException('Cache: Redis connection refused ('.$e->getMessage().')');
+			log_message('error', 'Cache: Redis connection refused ('.$e->getMessage().')');
 		}
-
-		if (isset($config['password']) && ! $this->_redis->auth($config['password']))
-		{
-			throw new RuntimeException('Cache: Redis authentication failed.');
-		}
-
-		// Initialize the index of serialized values.
-		$serialized = $this->_redis->sMembers('_ci_redis_serialized');
-		empty($serialized) OR $this->_serialized = array_flip($serialized);
 	}
 
 	// ------------------------------------------------------------------------
@@ -138,19 +131,35 @@ class CI_Cache_redis extends CI_Driver
 	/**
 	 * Get cache
 	 *
-	 * @param	string	Cache ID
+	 * @param	string	$key	Cache ID
 	 * @return	mixed
 	 */
 	public function get($key)
 	{
-		$value = $this->_redis->get($key);
+		$data = $this->_redis->hMGet($key, array('__ci_type', '__ci_value'));
 
-		if ($value !== FALSE && isset($this->_serialized[$key]))
+		if ( ! isset($data['__ci_type'], $data['__ci_value']) OR $data['__ci_value'] === FALSE)
 		{
-			return unserialize($value);
+			return FALSE;
 		}
 
-		return $value;
+		switch ($data['__ci_type'])
+		{
+			case 'array':
+			case 'object':
+				return unserialize($data['__ci_value']);
+			case 'boolean':
+			case 'integer':
+			case 'double': // Yes, 'double' is returned and NOT 'float'
+			case 'string':
+			case 'NULL':
+				return settype($data['__ci_value'], $data['__ci_type'])
+					? $data['__ci_value']
+					: FALSE;
+			case 'resource':
+			default:
+				return FALSE;
+		}
 	}
 
 	// ------------------------------------------------------------------------
@@ -166,23 +175,33 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function save($id, $data, $ttl = 60, $raw = FALSE)
 	{
-		if (is_array($data) OR is_object($data))
+		switch ($data_type = gettype($data))
 		{
-			if ( ! $this->_redis->sIsMember('_ci_redis_serialized', $id) && ! $this->_redis->sAdd('_ci_redis_serialized', $id))
-			{
+			case 'array':
+			case 'object':
+				$data = serialize($data);
+				break;
+			case 'boolean':
+			case 'integer':
+			case 'double': // Yes, 'double' is returned and NOT 'float'
+			case 'string':
+			case 'NULL':
+				break;
+			case 'resource':
+			default:
 				return FALSE;
-			}
+		}
 
-			isset($this->_serialized[$id]) OR $this->_serialized[$id] = TRUE;
-			$data = serialize($data);
+		if ( ! $this->_redis->hMSet($id, array('__ci_type' => $data_type, '__ci_value' => $data)))
+		{
+			return FALSE;
 		}
-		elseif (isset($this->_serialized[$id]))
+		elseif ($ttl)
 		{
-			$this->_serialized[$id] = NULL;
-			$this->_redis->sRemove('_ci_redis_serialized', $id);
+			$this->_redis->expireAt($id, time() + $ttl);
 		}
 
-		return $this->_redis->set($id, $data, $ttl);
+		return TRUE;
 	}
 
 	// ------------------------------------------------------------------------
@@ -190,23 +209,12 @@ class CI_Cache_redis extends CI_Driver
 	/**
 	 * Delete from cache
 	 *
-	 * @param	string	Cache key
+	 * @param	string	$key	Cache key
 	 * @return	bool
 	 */
 	public function delete($key)
 	{
-		if ($this->_redis->delete($key) !== 1)
-		{
-			return FALSE;
-		}
-
-		if (isset($this->_serialized[$key]))
-		{
-			$this->_serialized[$key] = NULL;
-			$this->_redis->sRemove('_ci_redis_serialized', $key);
-		}
-
-		return TRUE;
+		return ($this->_redis->delete($key) === 1);
 	}
 
 	// ------------------------------------------------------------------------
@@ -220,7 +228,7 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function increment($id, $offset = 1)
 	{
-		return $this->_redis->incr($id, $offset);
+		return $this->_redis->hIncrBy($id, 'data', $offset);
 	}
 
 	// ------------------------------------------------------------------------
@@ -234,7 +242,7 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function decrement($id, $offset = 1)
 	{
-		return $this->_redis->decr($id, $offset);
+		return $this->_redis->hIncrBy($id, 'data', -$offset);
 	}
 
 	// ------------------------------------------------------------------------
@@ -255,9 +263,9 @@ class CI_Cache_redis extends CI_Driver
 	/**
 	 * Get cache driver info
 	 *
-	 * @param	string	Not supported in Redis.
-	 *			Only included in order to offer a
-	 *			consistent cache API.
+	 * @param	string	$type	Not supported in Redis.
+	 *				Only included in order to offer a
+	 *				consistent cache API.
 	 * @return	array
 	 * @see		Redis::info()
 	 */
@@ -271,7 +279,7 @@ class CI_Cache_redis extends CI_Driver
 	/**
 	 * Get cache metadata
 	 *
-	 * @param	string	Cache key
+	 * @param	string	$key	Cache key
 	 * @return	array
 	 */
 	public function get_metadata($key)
@@ -298,13 +306,7 @@ class CI_Cache_redis extends CI_Driver
 	 */
 	public function is_supported()
 	{
-		if ( ! extension_loaded('redis'))
-		{
-			log_message('debug', 'The Redis extension must be loaded to use Redis cache.');
-			return FALSE;
-		}
-
-		return TRUE;
+		return extension_loaded('redis');
 	}
 
 	// ------------------------------------------------------------------------
diff --git a/system/libraries/Cache/drivers/Cache_wincache.php b/system/libraries/Cache/drivers/Cache_wincache.php
index 9cc6ff016..f296a5e26 100644
--- a/system/libraries/Cache/drivers/Cache_wincache.php
+++ b/system/libraries/Cache/drivers/Cache_wincache.php
@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2015, British Columbia Institute of Technology
+ * Copyright (c) 2014 - 2017, British Columbia Institute of Technology
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -28,10 +28,10 @@
  *
  * @package	CodeIgniter
  * @author	EllisLab Dev Team
- * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (http://ellislab.com/)
- * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2017, British Columbia Institute of Technology (http://bcit.ca/)
  * @license	http://opensource.org/licenses/MIT	MIT License
- * @link	http://codeigniter.com
+ * @link	https://codeigniter.com
  * @since	Version 3.0.0
  * @filesource
  */
@@ -52,6 +52,24 @@ defined('BASEPATH') OR exit('No direct script access allowed');
 class CI_Cache_wincache extends CI_Driver {
 
 	/**
+	 * Class constructor
+	 *
+	 * Only present so that an error message is logged
+	 * if APC is not available.
+	 *
+	 * @return	void
+	 */
+	public function __construct()
+	{
+		if ( ! $this->is_supported())
+		{
+			log_message('error', 'Cache: Failed to initialize Wincache; extension not loaded/enabled?');
+		}
+	}
+
+	// ------------------------------------------------------------------------
+
+	/**
 	 * Get
 	 *
 	 * Look for a value in the cache. If it exists, return the data,
@@ -194,13 +212,6 @@ class CI_Cache_wincache extends CI_Driver {
 	 */
 	public function is_supported()
 	{
-		if ( ! extension_loaded('wincache') OR ! ini_get('wincache.ucenabled'))
-		{
-			log_message('debug', 'The Wincache PHP extension must be loaded to use Wincache Cache.');
-			return FALSE;
-		}
-
-		return TRUE;
+		return (extension_loaded('wincache') && ini_get('wincache.ucenabled'));
 	}
-
 }