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diff --git a/program/lib/Roundcube/rcube_cache_shared.php b/program/lib/Roundcube/rcube_cache_shared.php
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+<?php
+
+/*
+ +-----------------------------------------------------------------------+
+ | This file is part of the Roundcube Webmail client |
+ | Copyright (C) 2011-2013, The Roundcube Dev Team |
+ | Copyright (C) 2011-2013, Kolab Systems AG |
+ | |
+ | Licensed under the GNU General Public License version 3 or |
+ | any later version with exceptions for skins & plugins. |
+ | See the README file for a full license statement. |
+ | |
+ | PURPOSE: |
+ | Shared (cross-user) caching engine |
+ +-----------------------------------------------------------------------+
+ | Author: Thomas Bruederli <roundcube@gmail.com> |
+ | Author: Aleksander Machniak <alec@alec.pl> |
+ +-----------------------------------------------------------------------+
+*/
+
+
+/**
+ * Interface class for accessing Roundcube shared cache
+ *
+ * @package Framework
+ * @subpackage Cache
+ * @author Thomas Bruederli <roundcube@gmail.com>
+ * @author Aleksander Machniak <alec@alec.pl>
+ */
+class rcube_cache
+{
+ /**
+ * Instance of database handler
+ *
+ * @var rcube_db|Memcache|bool
+ */
+ private $db;
+ private $type;
+ private $prefix;
+ private $ttl;
+ private $packed;
+ private $index;
+ private $table;
+ private $cache = array();
+ private $cache_changes = array();
+ private $cache_sums = array();
+
+
+ /**
+ * Object constructor.
+ *
+ * @param string $type Engine type ('db' or 'memcache' or 'apc')
+ * @param string $prefix Key name prefix
+ * @param string $ttl Expiration time of memcache/apc items
+ * @param bool $packed Enables/disabled data serialization.
+ * It's possible to disable data serialization if you're sure
+ * stored data will be always a safe string
+ */
+ function __construct($type, $prefix='', $ttl=0, $packed=true)
+ {
+ $rcube = rcube::get_instance();
+ $type = strtolower($type);
+
+ if ($type == 'memcache') {
+ $this->type = 'memcache';
+ $this->db = $rcube->get_memcache();
+ }
+ else if ($type == 'apc') {
+ $this->type = 'apc';
+ $this->db = function_exists('apc_exists'); // APC 3.1.4 required
+ }
+ else {
+ $this->type = 'db';
+ $this->db = $rcube->get_dbh();
+ $this->table = $this->db->table_name('cache_shared');
+ }
+
+ // convert ttl string to seconds
+ $ttl = get_offset_sec($ttl);
+ if ($ttl > 2592000) $ttl = 2592000;
+
+ $this->ttl = $ttl;
+ $this->packed = $packed;
+ $this->prefix = $prefix;
+ }
+
+
+ /**
+ * Returns cached value.
+ *
+ * @param string $key Cache key name
+ *
+ * @return mixed Cached value
+ */
+ function get($key)
+ {
+ if (!array_key_exists($key, $this->cache)) {
+ return $this->read_record($key);
+ }
+
+ return $this->cache[$key];
+ }
+
+
+ /**
+ * Sets (add/update) value in cache.
+ *
+ * @param string $key Cache key name
+ * @param mixed $data Cache data
+ */
+ function set($key, $data)
+ {
+ $this->cache[$key] = $data;
+ $this->cache_changed = true;
+ $this->cache_changes[$key] = true;
+ }
+
+
+ /**
+ * Returns cached value without storing it in internal memory.
+ *
+ * @param string $key Cache key name
+ *
+ * @return mixed Cached value
+ */
+ function read($key)
+ {
+ if (array_key_exists($key, $this->cache)) {
+ return $this->cache[$key];
+ }
+
+ return $this->read_record($key, true);
+ }
+
+
+ /**
+ * Sets (add/update) value in cache and immediately saves
+ * it in the backend, no internal memory will be used.
+ *
+ * @param string $key Cache key name
+ * @param mixed $data Cache data
+ *
+ * @param boolean True on success, False on failure
+ */
+ function write($key, $data)
+ {
+ return $this->write_record($key, $this->packed ? serialize($data) : $data);
+ }
+
+
+ /**
+ * Clears the cache.
+ *
+ * @param string $key Cache key name or pattern
+ * @param boolean $prefix_mode Enable it to clear all keys starting
+ * with prefix specified in $key
+ */
+ function remove($key=null, $prefix_mode=false)
+ {
+ // Remove all keys
+ if ($key === null) {
+ $this->cache = array();
+ $this->cache_changed = false;
+ $this->cache_changes = array();
+ $this->cache_sums = array();
+ }
+ // Remove keys by name prefix
+ else if ($prefix_mode) {
+ foreach (array_keys($this->cache) as $k) {
+ if (strpos($k, $key) === 0) {
+ $this->cache[$k] = null;
+ $this->cache_changes[$k] = false;
+ unset($this->cache_sums[$k]);
+ }
+ }
+ }
+ // Remove one key by name
+ else {
+ $this->cache[$key] = null;
+ $this->cache_changes[$key] = false;
+ unset($this->cache_sums[$key]);
+ }
+
+ // Remove record(s) from the backend
+ $this->remove_record($key, $prefix_mode);
+ }
+
+
+ /**
+ * Remove cache records older than ttl
+ */
+ function expunge()
+ {
+ if ($this->type == 'db' && $this->db) {
+ $this->db->query(
+ "DELETE FROM " . $this->table
+ . " WHERE cache_key LIKE ?"
+ . " AND " . $this->db->unixtimestamp('created') . " < ?",
+ $this->prefix . '.%',
+ time() - $this->ttl);
+ }
+ }
+
+
+ /**
+ * Writes the cache back to the DB.
+ */
+ function close()
+ {
+ if (!$this->cache_changed) {
+ return;
+ }
+
+ foreach ($this->cache as $key => $data) {
+ // The key has been used
+ if ($this->cache_changes[$key]) {
+ // Make sure we're not going to write unchanged data
+ // by comparing current md5 sum with the sum calculated on DB read
+ $data = $this->packed ? serialize($data) : $data;
+
+ if (!$this->cache_sums[$key] || $this->cache_sums[$key] != md5($data)) {
+ $this->write_record($key, $data);
+ }
+ }
+ }
+
+ $this->write_index();
+ }
+
+
+ /**
+ * Reads cache entry.
+ *
+ * @param string $key Cache key name
+ * @param boolean $nostore Enable to skip in-memory store
+ *
+ * @return mixed Cached value
+ */
+ private function read_record($key, $nostore=false)
+ {
+ if (!$this->db) {
+ return null;
+ }
+
+ if ($this->type != 'db') {
+ if ($this->type == 'memcache') {
+ $data = $this->db->get($this->ckey($key));
+ }
+ else if ($this->type == 'apc') {
+ $data = apc_fetch($this->ckey($key));
+ }
+
+ if ($data) {
+ $md5sum = md5($data);
+ $data = $this->packed ? unserialize($data) : $data;
+
+ if ($nostore) {
+ return $data;
+ }
+
+ $this->cache_sums[$key] = $md5sum;
+ $this->cache[$key] = $data;
+ }
+ else {
+ $this->cache[$key] = null;
+ }
+ }
+ else {
+ $sql_result = $this->db->limitquery(
+ "SELECT data, cache_key".
+ " FROM " . $this->table .
+ " WHERE cache_key = ?".
+ // for better performance we allow more records for one key
+ // get the newer one
+ " ORDER BY created DESC",
+ 0, 1, $this->prefix . '.' . $key);
+
+ if ($sql_arr = $this->db->fetch_assoc($sql_result)) {
+ $md5sum = $sql_arr['data'] ? md5($sql_arr['data']) : null;
+ if ($sql_arr['data']) {
+ $data = $this->packed ? unserialize($sql_arr['data']) : $sql_arr['data'];
+ }
+
+ if ($nostore) {
+ return $data;
+ }
+
+ $this->cache[$key] = $data;
+ $this->cache_sums[$key] = $md5sum;
+ }
+ else {
+ $this->cache[$key] = null;
+ }
+ }
+
+ return $this->cache[$key];
+ }
+
+
+ /**
+ * Writes single cache record into DB.
+ *
+ * @param string $key Cache key name
+ * @param mxied $data Serialized cache data
+ *
+ * @param boolean True on success, False on failure
+ */
+ private function write_record($key, $data)
+ {
+ if (!$this->db) {
+ return false;
+ }
+
+ if ($this->type == 'memcache' || $this->type == 'apc') {
+ return $this->add_record($this->ckey($key), $data);
+ }
+
+ $key_exists = array_key_exists($key, $this->cache_sums);
+ $key = $this->prefix . '.' . $key;
+
+ // Remove NULL rows (here we don't need to check if the record exist)
+ if ($data == 'N;') {
+ $this->db->query("DELETE FROM " . $this->table . " WHERE cache_key = ?", $key);
+ return true;
+ }
+
+ // update existing cache record
+ if ($key_exists) {
+ $result = $this->db->query(
+ "UPDATE " . $this->table .
+ " SET created = " . $this->db->now() . ", data = ?" .
+ " WHERE cache_key = ?",
+ $data, $key);
+ }
+ // add new cache record
+ else {
+ // for better performance we allow more records for one key
+ // so, no need to check if record exist (see rcube_cache::read_record())
+ $result = $this->db->query(
+ "INSERT INTO ".$this->table.
+ " (created, cache_key, data)".
+ " VALUES (".$this->db->now().", ?, ?)",
+ $key, $data);
+ }
+
+ return $this->db->affected_rows($result);
+ }
+
+
+ /**
+ * Deletes the cache record(s).
+ *
+ * @param string $key Cache key name or pattern
+ * @param boolean $prefix_mode Enable it to clear all keys starting
+ * with prefix specified in $key
+ */
+ private function remove_record($key=null, $prefix_mode=false)
+ {
+ if (!$this->db) {
+ return;
+ }
+
+ if ($this->type != 'db') {
+ $this->load_index();
+
+ // Remove all keys
+ if ($key === null) {
+ foreach ($this->index as $key) {
+ $this->delete_record($key, false);
+ }
+ $this->index = array();
+ }
+ // Remove keys by name prefix
+ else if ($prefix_mode) {
+ foreach ($this->index as $k) {
+ if (strpos($k, $key) === 0) {
+ $this->delete_record($k);
+ }
+ }
+ }
+ // Remove one key by name
+ else {
+ $this->delete_record($key);
+ }
+
+ return;
+ }
+
+ // Remove all keys (in specified cache)
+ if ($key === null) {
+ $where = " WHERE cache_key LIKE " . $this->db->quote($this->prefix.'.%');
+ }
+ // Remove keys by name prefix
+ else if ($prefix_mode) {
+ $where = " WHERE cache_key LIKE " . $this->db->quote($this->prefix.'.'.$key.'%');
+ }
+ // Remove one key by name
+ else {
+ $where = " WHERE cache_key = " . $this->db->quote($this->prefix.'.'.$key);
+ }
+
+ $this->db->query("DELETE FROM " . $this->table . $where);
+ }
+
+
+ /**
+ * Adds entry into memcache/apc DB.
+ *
+ * @param string $key Cache key name
+ * @param mxied $data Serialized cache data
+ * @param bollean $index Enables immediate index update
+ *
+ * @param boolean True on success, False on failure
+ */
+ private function add_record($key, $data, $index=false)
+ {
+ if ($this->type == 'memcache') {
+ $result = $this->db->replace($key, $data, MEMCACHE_COMPRESSED, $this->ttl);
+ if (!$result) {
+ $result = $this->db->set($key, $data, MEMCACHE_COMPRESSED, $this->ttl);
+ }
+ }
+ else if ($this->type == 'apc') {
+ if (apc_exists($key)) {
+ apc_delete($key);
+ }
+ $result = apc_store($key, $data, $this->ttl);
+ }
+
+ // Update index
+ if ($index && $result) {
+ $this->load_index();
+
+ if (array_search($key, $this->index) === false) {
+ $this->index[] = $key;
+ $data = serialize($this->index);
+ $this->add_record($this->ikey(), $data);
+ }
+ }
+
+ return $result;
+ }
+
+
+ /**
+ * Deletes entry from memcache/apc DB.
+ */
+ private function delete_record($key, $index=true)
+ {
+ if ($this->type == 'memcache') {
+ // #1488592: use 2nd argument
+ $this->db->delete($this->ckey($key), 0);
+ }
+ else {
+ apc_delete($this->ckey($key));
+ }
+
+ if ($index) {
+ if (($idx = array_search($key, $this->index)) !== false) {
+ unset($this->index[$idx]);
+ }
+ }
+ }
+
+
+ /**
+ * Writes the index entry into memcache/apc DB.
+ */
+ private function write_index()
+ {
+ if (!$this->db) {
+ return;
+ }
+
+ if ($this->type == 'db') {
+ return;
+ }
+
+ $this->load_index();
+
+ // Make sure index contains new keys
+ foreach ($this->cache as $key => $value) {
+ if ($value !== null) {
+ if (array_search($key, $this->index) === false) {
+ $this->index[] = $key;
+ }
+ }
+ }
+
+ $data = serialize($this->index);
+ $this->add_record($this->ikey(), $data);
+ }
+
+
+ /**
+ * Gets the index entry from memcache/apc DB.
+ */
+ private function load_index()
+ {
+ if (!$this->db) {
+ return;
+ }
+
+ if ($this->index !== null) {
+ return;
+ }
+
+ $index_key = $this->ikey();
+
+ if ($this->type == 'memcache') {
+ $data = $this->db->get($index_key);
+ }
+ else if ($this->type == 'apc') {
+ $data = apc_fetch($index_key);
+ }
+
+ $this->index = $data ? unserialize($data) : array();
+ }
+
+
+ /**
+ * Creates cache key name (for memcache and apc)
+ *
+ * @param string $key Cache key name
+ *
+ * @return string Cache key
+ */
+ private function ckey($key)
+ {
+ return $this->prefix . ':' . $key;
+ }
+
+
+ /**
+ * Creates index cache key name (for memcache and apc)
+ *
+ * @return string Cache key
+ */
+ private function ikey()
+ {
+ // This way each cache will have its own index
+ return $this->prefix . 'INDEX';
+ }
+}