Add Redis caching support.

Compatible with the phpredis extension:
https://github.com/nicolasff/phpredis

inc/cache.php

@@ -19,6 +19,14 @@ class Cache {
 				self::$cache = new Memcached();
 				self::$cache->addServers($config['cache']['memcached']);
 				break;
+			case 'redis':
+				self::$cache = new Redis();
+				self::$cache->connect($config['cache']['redis'][0], $config['cache']['redis'][1]);
+				if ($config['cache']['redis'][2]) {
+					self::$cache->auth($config['cache']['redis'][2]);
+				}
+				self::$cache->select($config['cache']['redis'][3]) or die('cache select failure');
+				break;
 			case 'php':
 				self::$cache = array();
 				break;
@@ -45,6 +53,11 @@ class Cache {
 			case 'php':
 				$data = isset(self::$cache[$key]) ? self::$cache[$key] : false;
 				break;
+			case 'redis':
+				if (!self::$cache)
+					self::init();
+				$data = json_decode(self::$cache->get($key), true);
+				break;
 		}
 		
 		// debug
@@ -68,6 +81,11 @@ class Cache {
 					self::init();
 				self::$cache->set($key, $value, $expires);
 				break;
+			case 'redis':
+				if (!self::$cache)
+					self::init();
+				self::$cache->setex($key, $expires, json_encode($value));
+				break;
 			case 'apc':
 				apc_store($key, $value, $expires);
 				break;
@@ -86,6 +104,7 @@ class Cache {
 		
 		switch ($config['cache']['enabled']) {
 			case 'memcached':
+			case 'redis':
 				if (!self::$cache)
 					self::init();
 				self::$cache->delete($key);
@@ -114,6 +133,10 @@ class Cache {
 			case 'php':
 				self::$cache[$key] = array();
 				break;
+			case 'redis':
+				if (!self::$cache)
+					self::init();
+				return self::$cache->flushDB();
 		}
 		
 		return false;

inc/config.php

@@ -91,6 +91,7 @@
  	
  	$config['cache']['enabled'] = false;
  	// $config['cache']['enabled'] = 'memcached';
+ 	// $config['cache']['enabled'] = 'redis';
  	// $config['cache']['enabled'] = 'apc';
  	// $config['cache']['enabled'] = 'xcache';
  	
@@ -104,6 +105,11 @@
 	$config['cache']['memcached'] = array(
 		array('localhost', 11211)
 	);
+
+	// Redis server to use. Location, port, password, database id.
+	// Note that Tinyboard may clear the database at times, so you may want to pick a
+	// database id just for Tinyboard to use.
+	$config['cache']['redis'] = array('localhost', 6379, '', 1);
 	
 /*
  * ====================