Wordpress/wp-includes/cache.php

344 lines
8.8 KiB
PHP

<?php
function wp_cache_add($key, $data, $flag = '', $expire = 0) {
global $wp_object_cache;
return $wp_object_cache->add($key, $data, $flag, $expire);
}
function wp_cache_close() {
global $wp_object_cache;
return $wp_object_cache->save();
}
function wp_cache_delete($id, $flag = '') {
global $wp_object_cache;
return $wp_object_cache->delete($id, $flag);
}
function wp_cache_flush() {
global $wp_object_cache;
}
function wp_cache_get($id, $flag = '') {
global $wp_object_cache;
return $wp_object_cache->get($id, $flag);
}
function wp_cache_init() {
global $wp_object_cache;
$wp_object_cache = new WP_Object_Cache();
}
function wp_cache_replace($key, $data, $flag = '', $expire = 0) {
global $wp_object_cache;
return $wp_object_cache->replace($key, $data, $flag, $expire);
}
function wp_cache_set($key, $data, $flag = '', $expire = 0) {
global $wp_object_cache;
return $wp_object_cache->set($key, $data, $flag, $expire);
}
define('CACHE_SERIAL_HEADER', "<?php\n//");
define('CACHE_SERIAL_FOOTER', "\n?".">");
class WP_Object_Cache {
var $cache_dir;
var $cache_enabled = false;
var $expiration_time = 86400;
var $use_flock = false;
var $flock_filename = 'wp_object_cache.lock';
var $sem_id = 5454;
var $mutex;
var $cache = array ();
var $dirty_objects = array ();
var $non_existant_objects = array();
var $global_groups = array('users', 'usermeta');
var $blog_id;
var $cold_cache_hits = 0;
var $warm_cache_hits = 0;
var $cache_misses = 0;
function add($id, $data, $group = 'default', $expire = '') {
if ( empty($group) )
$group = 'default';
if ( false !== $this->get($id, $group, false) )
return false;
return $this->set($id, $data, $group, $expire);
}
function delete($id, $group = 'default') {
if ( empty($group) )
$group = 'default';
if ( false === $this->get($id, $group, false) )
return false;
unset ($this->cache[$group][$id]);
$this->non_existant_objects[$group][$id] = true;
$this->dirty_objects[$group][] = $id;
return true;
}
function get($id, $group = 'default', $count_hits = true) {
if ( empty($group) )
$group = 'default';
if (isset ($this->cache[$group][$id])) {
if ( $count_hits )
$this->warm_cache_hits += 1;
return $this->cache[$group][$id];
}
if ( isset($this->non_existant_objects[$group][$id]) )
return false;
// If caching is not enabled, we have to fall back to pulling from the DB.
if (!$this->cache_enabled) {
if (!isset ($this->cache[$group]))
$this->load_group_from_db($group);
if (isset ($this->cache[$group][$id])) {
$this->cold_cache_hits += 1;
return $this->cache[$group][$id];
}
$this->non_existant_objects[$group][$id] = true;
$this->cache_misses += 1;
return false;
}
$cache_file = $this->cache_dir . $this->get_group_dir($group) . "/" . md5($id . DB_PASSWORD) . '.php';
if (!file_exists($cache_file)) {
$this->non_existant_objects[$group][$id] = true;
$this->cache_misses += 1;
return false;
}
// If the object has expired, remove it from the cache and return false to force
// a refresh.
$now = time();
if ( (filemtime($cache_file) + $this->expiration_time) <= $now ) {
$this->cache_misses += 1;
$this->delete($id, $group);
return false;
}
$this->cache[$group][$id] = unserialize(substr(@ file_get_contents($cache_file), strlen(CACHE_SERIAL_HEADER), -strlen(CACHE_SERIAL_FOOTER)));
if ( false === $this->cache[$group][$id])
$this->cache[$group][$id] = '';
$this->cold_cache_hits += 1;
return $this->cache[$group][$id];
}
function get_group_dir($group) {
if ( false !== array_search($group, $this->global_groups) )
return $group;
return "{$this->blog_id}/$group";
}
function load_group_from_db($group) {
global $wpdb;
if ('category' == $group) {
$this->cache['category'] = array ();
if ($dogs = $wpdb->get_results("SELECT * FROM $wpdb->categories")) {
foreach ($dogs as $catt)
$this->cache['category'][$catt->cat_ID] = $catt;
foreach ($this->cache['category'] as $catt) {
$curcat = $catt->cat_ID;
$fullpath = '/'.$this->cache['category'][$catt->cat_ID]->category_nicename;
while ($this->cache['category'][$curcat]->category_parent != 0) {
$curcat = $this->cache['category'][$curcat]->category_parent;
$fullpath = '/'.$this->cache['category'][$curcat]->category_nicename.$fullpath;
}
$this->cache['category'][$catt->cat_ID]->fullpath = $fullpath;
}
}
} else if ( 'options' == $group ) {
$wpdb->hide_errors();
if ( !$options = $wpdb->get_results("SELECT option_name, option_value FROM $wpdb->options WHERE autoload = 'yes'") ) {
$options = $wpdb->get_results("SELECT option_name, option_value FROM $wpdb->options");
}
$wpdb->show_errors();
foreach ($options as $option) {
$this->cache['options'][$option->option_name] = $option->option_value;
}
}
}
function make_group_dir($group, $perms) {
$group_dir = $this->get_group_dir($group);
$make_dir = '';
foreach ( split('/', $group_dir) as $subdir) {
$make_dir .= "$subdir/";
if (!file_exists($this->cache_dir . $make_dir)) {
if (!mkdir($this->cache_dir . $make_dir))
break;
@ chmod($this->cache_dir . $make_dir, $perms);
}
if (!file_exists($this->cache_dir . $make_dir . "index.php")) {
touch($this->cache_dir . $make_dir . "index.php");
}
}
return $this->cache_dir . "$group_dir/";
}
function replace($id, $data, $group = 'default', $expire = '') {
if ( empty($group) )
$group = 'default';
if ( false === $this->get($id, $group, false) )
return false;
return $this->set($id, $data, $group, $expire);
}
function set($id, $data, $group = 'default', $expire = '') {
if ( empty($group) )
$group = 'default';
if ( NULL == $data)
$data = '';
$this->cache[$group][$id] = $data;
unset($this->non_existant_objects[$group][$id]);
$this->dirty_objects[$group][] = $id;
return true;
}
function save() {
//$this->stats();
if (!$this->cache_enabled)
return;
if (empty ($this->dirty_objects))
return;
// Give the new dirs the same perms as wp-content.
$stat = stat(ABSPATH.'wp-content');
$dir_perms = $stat['mode'] & 0000777; // Get the permission bits.
// Make the base cache dir.
if (!file_exists($this->cache_dir)) {
if (!mkdir($this->cache_dir))
return;
@ chmod($this->cache_dir, $dir_perms);
}
if (!file_exists($this->cache_dir . "index.php")) {
touch($this->cache_dir . "index.php");
}
// Acquire a write lock. Semaphore preferred. Fallback to flock.
if (function_exists('sem_get')) {
$this->use_flock = false;
$mutex = sem_get($this->sem_id, 1, 0644 | IPC_CREAT, 1);
sem_acquire($mutex);
} else {
$this->use_flock = true;
$mutex = fopen($this->cache_dir.$this->flock_filename, 'w');
flock($mutex, LOCK_EX);
}
// Loop over dirty objects and save them.
foreach ($this->dirty_objects as $group => $ids) {
$group_dir = $this->make_group_dir($group, $dir_perms);
$ids = array_unique($ids);
foreach ($ids as $id) {
$cache_file = $group_dir . md5($id . DB_PASSWORD) . '.php';
// Remove the cache file if the key is not set.
if ( ! isset($this->cache[$group][$id]) ) {
if ( file_exists($cache_file) )
unlink($cache_file);
continue;
}
$temp_file = tempnam($group_dir, 'tmp');
$serial = CACHE_SERIAL_HEADER . serialize($this->cache[$group][$id]) . CACHE_SERIAL_FOOTER;
$fd = fopen($temp_file, 'w');
fputs($fd, $serial);
fclose($fd);
if (!@rename($temp_file, $cache_file)) {
if (copy ($temp_file, $cache_file)) {
unlink($temp_file);
}
}
}
}
// Release write lock.
if ($this->use_flock)
flock($mutex, LOCK_UN);
else
sem_release($mutex);
}
function stats() {
echo "<p>";
echo "<strong>Cold Cache Hits:</strong> {$this->cold_cache_hits}<br/>";
echo "<strong>Warm Cache Hits:</strong> {$this->warm_cache_hits}<br/>";
echo "<strong>Cache Misses:</strong> {$this->cache_misses}<br/>";
echo "</p>";
foreach ($this->cache as $group => $cache) {
echo "<p>";
echo "<strong>Group:</strong> $group<br/>";
echo "<strong>Cache:</strong>";
echo "<pre>";
print_r($cache);
echo "</pre>";
if ( isset($this->dirty_objects[$group]) ) {
echo "<strong>Dirty Objects:</strong>";
echo "<pre>";
print_r(array_unique($this->dirty_objects[$group]));
echo "</pre>";
echo "</p>";
}
}
}
function WP_Object_Cache() {
global $blog_id;
if ( defined('DISABLE_CACHE') )
return;
if ( defined('CACHE_PATH') )
$this->cache_dir = CACHE_PATH;
else
$this->cache_dir = ABSPATH.'wp-content/cache/';
if ( is_dir($this->cache_dir) ) {
if ( is_writable($this->cache_dir) )
$this->cache_enabled = true;
} else if (is_writable(ABSPATH.'wp-content')) {
$this->cache_enabled = true;
}
if ( defined('CACHE_EXPIRATION_TIME') )
$this->expiration_time = CACHE_EXPIRATION_TIME;
$this->blog_id = md5($blog_id);
}
}
?>