Index: cache.php =================================================================== --- cache.php (revision 6542) +++ cache.php (working copy) @@ -1,55 +1,219 @@ add($key, $data, $flag, $expire); } +/** + * wp_cache_close() - Closes the cache + * + * This function has ceased to do anything since WordPress 2.5. + * The functionality was removed along with the rest of the + * persistant cache. + * + * @since 2.0 + * + * @return bool Always returns True + */ function wp_cache_close() { return true; } +/** + * wp_cache_delete() - Removes the cache contents matching ID and flag + * + * @since 2.0 + * @uses $wp_object_cache Object Cache Class + * @see WP_Object_Cache::delete() + * + * @param int|string $id What the contents in the cache are called + * @param string $flag Where the cache contents are grouped + * @return bool True on successful removal, false on failure + */ function wp_cache_delete($id, $flag = '') { global $wp_object_cache; return $wp_object_cache->delete($id, $flag); } +/** + * wp_cache_flush() - Removes all cache items + * + * @since 2.0 + * @uses $wp_object_cache Object Cache Class + * @see WP_Object_Cache::flush() + * + * @return bool Always returns true + */ function wp_cache_flush() { global $wp_object_cache; return $wp_object_cache->flush(); } +/** + * wp_cache_get() - Retrieves the cache contents from the cache by ID and flag + * + * @since 2.0 + * @uses $wp_object_cache Object Cache Class + * @see WP_Object_Cache::get() + * + * @param int|string $id What the contents in the cache are called + * @param string $flag Where the cache contents are grouped + * @return bool|mixed False on failure to retrieve contents or the cache contents on success + */ function wp_cache_get($id, $flag = '') { global $wp_object_cache; return $wp_object_cache->get($id, $flag); } +/** + * wp_cache_init() - Sets up Object Cache Global and assigns it + * + * @since 2.0 + * @global WP_Object_Cache $wp_object_cache WordPress Object Cache + */ function wp_cache_init() { $GLOBALS['wp_object_cache'] =& new WP_Object_Cache(); } +/** + * wp_cache_replace() - Replaces the contents of the cache with new data + * + * @since 2.0 + * @uses $wp_object_cache Object Cache Class + * @see WP_Object_Cache::replace() + * + * @param int|string $id What to call the contents in the cache + * @param mixed $data The contents to store in the cache + * @param string $flag Where to group the cache contents + * @param int $expire When to expire the cache contents + * @return bool False if cache ID and group already exists, true on success + */ function wp_cache_replace($key, $data, $flag = '', $expire = 0) { global $wp_object_cache; return $wp_object_cache->replace($key, $data, $flag, $expire); } +/** + * wp_cache_set() - Saves the data to the cache + * + * @since 2.0 + * @uses $wp_object_cache Object Cache Class + * @see WP_Object_Cache::set() + * + * @param int|string $id What to call the contents in the cache + * @param mixed $data The contents to store in the cache + * @param string $flag Where to group the cache contents + * @param int $expire When to expire the cache contents + * @return bool False if cache ID and group already exists, true on success + */ function wp_cache_set($key, $data, $flag = '', $expire = 0) { global $wp_object_cache; return $wp_object_cache->set($key, $data, $flag, $expire); } +/** + * WordPress Object Cache + * + * The WordPress Object Cache is used to save on trips to the database. + * The Object Cache stores all of the cache data to memory and makes the + * cache contents available by using a key, which is used to name and + * later retrieve the cache contents. + * + * The Object Cache can be replaced by other caching mechanisms by placing + * files in the wp-content folder which is looked at in wp-settings. If + * that file exists, then this file will not be included. + * + * @package WordPress + * @subpackage Cache + * @since 2.0 + */ class WP_Object_Cache { + + /** + * Holds the cached objects + * + * @var array + * @access private + * @since 2.0 + */ var $cache = array (); + + /** + * Cache objects that do not exist in the cache + * + * @var array + * @access private + * @since 2.0 + */ var $non_existant_objects = array (); + + /** + * Object caches that are global + * + * @var array + * @access private + * @since 2.0 + */ var $global_groups = array ('users', 'userlogins', 'usermeta'); + + /** + * The amount of times the cache data was already stored in the cache. + * + * @since 2.5 + * @access private + * @var int + */ var $cache_hits = 0; + + /** + * Amount of times the cache did not have the request in cache + * + * @var int + * @access public + * @since 2.0 + */ var $cache_misses = 0; + /** + * Adds data to the cache if it doesn't already exist. + * + * @uses WP_Object_Cache::get Checks to see if the cache already has data. + * @uses WP_Object_Cache::set Sets the data after the checking the cache contents existance. + * + * @since 2.0 + * + * @param int|string $id What to call the contents in the cache + * @param mixed $data The contents to store in the cache + * @param string $group Where to group the cache contents + * @param int $expire When to expire the cache contents + * @return bool False if cache ID and group already exists, true on success + */ function add($id, $data, $group = 'default', $expire = '') { if (empty ($group)) $group = 'default'; @@ -60,6 +224,23 @@ return $this->set($id, $data, $group, $expire); } + /** + * Remove the contents of the cache ID in the group + * + * If the cache ID does not exist in the group and $force parameter + * is set to false, then nothing will happen. The $force parameter + * is set to false by default. + * + * On success the group and the id will be added to the + * $non_existant_objects property in the class. + * + * @since 2.0 + * + * @param int|string $id What the contents in the cache are called + * @param string $group Where the cache contents are grouped + * @param bool $force Optional. Whether to force the unsetting of the cache ID in the group + * @return bool False if the contents weren't deleted and true on success + */ function delete($id, $group = 'default', $force = false) { if (empty ($group)) $group = 'default'; @@ -72,12 +253,38 @@ return true; } + /** + * Clears the object cache of all data + * + * @since 2.0 + * + * @return bool Always returns true + */ function flush() { $this->cache = array (); return true; } + /** + * Retrieves the cache contents, if it exists + * + * The contents will be first attempted to be retrieved by searching + * by the ID in the cache group. If the cache is hit (success) then + * the contents are returned. + * + * On failure, the $non_existant_objects property is checked and if + * the cache group and ID exist in there the cache misses will not be + * incremented. If not in the nonexistant objects property, then the + * cache misses will be incremented and the cache group and ID will + * be added to the nonexistant objects. + * + * @since 2.0 + * + * @param int|string $id What the contents in the cache are called + * @param string $group Where the cache contents are grouped + * @return bool|mixed False on failure to retrieve contents or the cache contents on success + */ function get($id, $group = 'default') { if (empty ($group)) $group = 'default'; @@ -95,6 +302,18 @@ return false; } + /** + * Replace the contents in the cache, if contents already exist + * + * @since 2.0 + * @see WP_Object_Cache::set() + * + * @param int|string $id What to call the contents in the cache + * @param mixed $data The contents to store in the cache + * @param string $group Where to group the cache contents + * @param int $expire When to expire the cache contents + * @return bool False if not exists, true if contents were replaced + */ function replace($id, $data, $group = 'default', $expire = '') { if (empty ($group)) $group = 'default'; @@ -105,6 +324,27 @@ return $this->set($id, $data, $group, $expire); } + /** + * Sets the data contents into the cache + * + * The cache contents is grouped by the $group parameter followed + * by the $id. This allows for duplicate ids in unique groups. + * Therefore, naming of the group should be used with care and + * should follow normal function naming guidelines outside of + * core WordPress usage. + * + * The $expire parameter is not used, because the cache will + * automatically expire for each time a page is accessed and PHP + * finishes. The method is more for cache plugins which use files. + * + * @since 2.0 + * + * @param int|string $id What to call the contents in the cache + * @param mixed $data The contents to store in the cache + * @param string $group Where to group the cache contents + * @param int $expire Not Used + * @return bool Always returns true + */ function set($id, $data, $group = 'default', $expire = '') { if (empty ($group)) $group = 'default'; @@ -118,6 +358,14 @@ return true; } + /** + * Echos the stats of the caching. + * + * Gives the cache hits, and cache misses. Also prints every cached + * group, key and the data. + * + * @since 2.0 + */ function stats() { echo "

"; echo "Cache Hits: {$this->cache_hits}
"; @@ -134,14 +382,36 @@ } } + /** + * PHP4 constructor; Calls PHP 5 style constructor + * + * @since 2.0 + * + * @return WP_Object_Cache + */ function WP_Object_Cache() { return $this->__construct(); } + /** + * Sets up object properties; PHP 5 style constructor + * + * @since 2.0.8 + * @return null|WP_Object_Cache If cache is disabled, returns null. + */ function __construct() { - register_shutdown_function(array(&$this, "__destruct")); + register_shutdown_function(array(&$this, "__destruct")); /** @todo This should be moved to the PHP4 style constructor, PHP5 already calls __destruct() */ } + /** + * Will save the object cache before object is completely destroyed. + * + * Called upon object destruction, which should be when PHP ends. + * + * @since 2.0.8 + * + * @return bool True value. Won't be used by PHP + */ function __destruct() { return true; }