2017-03-11 02:51:06 +07:00

384 lines
12 KiB
PHP

<?php
/**
* ~~summary~~
*
* ~~description~~
*
* PHP version 5
*
* @category Caching
* @package PEAR2_Cache_SHM
* @author Vasil Rangelov <boen.robot@gmail.com>
* @copyright 2011 Vasil Rangelov
* @license http://www.gnu.org/copyleft/lesser.html LGPL License 2.1
* @version 0.1.3
* @link http://pear2.php.net/PEAR2_Cache_SHM
*/
/**
* The namespace declaration.
*/
namespace PEAR2\Cache\SHM\Adapter;
/**
* Throws exceptions from this namespace, and extends from this class.
*/
use PEAR2\Cache\SHM;
/**
* {@link Wincache::getIterator()} returns this object.
*/
use ArrayObject;
/**
* Shared memory adapter for the WinCache extension.
*
* @category Caching
* @package PEAR2_Cache_SHM
* @author Vasil Rangelov <boen.robot@gmail.com>
* @license http://www.gnu.org/copyleft/lesser.html LGPL License 2.1
* @link http://pear2.php.net/PEAR2_Cache_SHM
*/
class Wincache extends SHM
{
/**
* @var string ID of the current storage.
*/
protected $persistentId;
/**
* List of persistent IDs.
*
* A list of persistent IDs within the current request (as keys) with an int
* (as a value) specifying the number of instances in the current request.
* Used as an attempt to ensure implicit lock releases on destruction.
* @var array
*/
protected static $requestInstances = array();
/**
* @var array Array of lock names obtained during the current request.
*/
protected static $locksBackup = array();
/**
* Creates a new shared memory storage.
*
* Estabilishes a separate persistent storage.
*
* @param string $persistentId The ID for the storage. The storage will be
* reused if it exists, or created if it doesn't exist. Data and locks
* are namespaced by this ID.
*/
public function __construct($persistentId)
{
$this->persistentId
= static::encodeLockName(__CLASS__ . ' ' . $persistentId) . ' ';
if (isset(static::$requestInstances[$this->persistentId])) {
static::$requestInstances[$this->persistentId]++;
} else {
static::$requestInstances[$this->persistentId] = 1;
static::$locksBackup[$this->persistentId] = array();
}
}
/**
* Encodes a lock name
*
* Encodes a lock name, so that it can be properly obtained. The scheme used
* is a subset of URL encoding, with only the "%" and "\" characters being
* escaped. The encoding itself is necessary, since lock names can't contain
* the "\" character.
*
* @param string $name The lock name to encode.
*
* @return string The encoded name.
* @link http://msdn.microsoft.com/en-us/library/ms682411(VS.85).aspx
*/
protected static function encodeLockName($name)
{
return str_replace(array('%', '\\'), array('%25', '%5C'), $name);
}
/**
* Checks if the adapter meets its requirements.
*
* @return bool TRUE on success, FALSE on failure.
*/
public static function isMeetingRequirements()
{
return extension_loaded('wincache')
&& version_compare(phpversion('wincache'), '1.1.0', '>=')
&& ini_get('wincache.ucenabled')
&& ('cli' !== PHP_SAPI || ini_get('wincache.enablecli'));
}
/**
* Releases any locks obtained by this instance as soon as there are no more
* references to the object's persistent ID.
*/
public function __destruct()
{
if (0 === --static::$requestInstances[$this->persistentId]) {
foreach (static::$locksBackup[$this->persistentId] as $key) {
wincache_unlock(
$this->persistentId . static::encodeLockName($key)
);
}
}
}
/**
* Obtains a named lock.
*
* @param string $key Name of the key to obtain. Note that $key may
* repeat for each distinct $persistentId.
* @param double $timeout Ignored with WinCache. Script will always block if
* the lock can't be immediatly obtained.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function lock($key, $timeout = null)
{
$result = wincache_lock(
$this->persistentId . static::encodeLockName($key)
);
if ($result) {
static::$locksBackup[$this->persistentId] = $key;
}
return $result;
}
/**
* Releases a named lock.
*
* @param string $key Name of the key to release. Note that $key may
* repeat for each distinct $persistentId.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function unlock($key)
{
$result = wincache_unlock(
$this->persistentId . static::encodeLockName($key)
);
if ($result) {
unset(static::$locksBackup[$this->persistentId][array_search(
$key,
static::$locksBackup[$this->persistentId],
true
)]);
}
return $result;
}
/**
* Checks if a specified key is in the storage.
*
* @param string $key Name of key to check.
*
* @return bool TRUE if the key is in the storage, FALSE otherwise.
*/
public function exists($key)
{
return wincache_ucache_exists($this->persistentId . $key);
}
/**
* Adds a value to the shared memory storage.
*
* Sets a value to the storage if it doesn't exist, or fails if it does.
*
* @param string $key Name of key to associate the value with.
* @param mixed $value Value for the specified key.
* @param int $ttl Seconds to store the value. If set to 0 indicates no
* time limit.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function add($key, $value, $ttl = 0)
{
return wincache_ucache_add($this->persistentId . $key, $value, $ttl);
}
/**
* Sets a value in the shared memory storage.
*
* Adds a value to the storage if it doesn't exist, overwrites it otherwise.
*
* @param string $key Name of key to associate the value with.
* @param mixed $value Value for the specified key.
* @param int $ttl Seconds to store the value. If set to 0 indicates no
* time limit.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function set($key, $value, $ttl = 0)
{
return wincache_ucache_set($this->persistentId . $key, $value, $ttl);
}
/**
* Gets a value from the shared memory storage.
*
* Gets the current value, or throws an exception if it's not stored.
*
* @param string $key Name of key to get the value of.
*
* @return mixed The current value of the specified key.
*/
public function get($key)
{
$value = wincache_ucache_get($this->persistentId . $key, $success);
if (!$success) {
throw new SHM\InvalidArgumentException(
'Unable to fetch key. No such key, or key has expired.',
300
);
}
return $value;
}
/**
* Deletes a value from the shared memory storage.
*
* @param string $key Name of key to delete.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function delete($key)
{
return wincache_ucache_delete($this->persistentId . $key);
}
/**
* Increases a value from the shared memory storage.
*
* Increases a value from the shared memory storage. Unlike a plain
* set($key, get($key)+$step) combination, this function also implicitly
* performs locking.
*
* @param string $key Name of key to increase.
* @param int $step Value to increase the key by.
*
* @return int The new value.
*/
public function inc($key, $step = 1)
{
$newValue = wincache_ucache_inc(
$this->persistentId . $key,
(int) $step,
$success
);
if (!$success) {
throw new SHM\InvalidArgumentException(
'Unable to increase the value. Are you sure the value is int?',
301
);
}
return $newValue;
}
/**
* Decreases a value from the shared memory storage.
*
* Decreases a value from the shared memory storage. Unlike a plain
* set($key, get($key)-$step) combination, this function also implicitly
* performs locking.
*
* @param string $key Name of key to decrease.
* @param int $step Value to decrease the key by.
*
* @return int The new value.
*/
public function dec($key, $step = 1)
{
$newValue = wincache_ucache_dec(
$this->persistentId . $key,
(int) $step,
$success
);
if (!$success) {
throw new SHM\InvalidArgumentException(
'Unable to decrease the value. Are you sure the value is int?',
302
);
}
return $newValue;
}
/**
* Sets a new value if a key has a certain value.
*
* Sets a new value if a key has a certain value. This function only works
* when $old and $new are longs.
*
* @param string $key Key of the value to compare and set.
* @param int $old The value to compare the key against.
* @param int $new The value to set the key to.
*
* @return bool TRUE on success, FALSE on failure.
*/
public function cas($key, $old, $new)
{
return wincache_ucache_cas($this->persistentId . $key, $old, $new);
}
/**
* Clears the persistent storage.
*
* Clears the persistent storage, i.e. removes all keys. Locks are left
* intact.
*
* @return void
*/
public function clear()
{
$info = wincache_ucache_info();
foreach ($info['ucache_entries'] as $entry) {
if (!$entry['is_session']
&& 0 === strpos($entry['key_name'], $this->persistentId)
) {
wincache_ucache_delete($entry['key_name']);
}
}
}
/**
* Retrieve an external iterator
*
* Returns an external iterator.
*
* @param string|null $filter A PCRE regular expression.
* Only matching keys will be iterated over.
* Setting this to NULL matches all keys of this instance.
* @param bool $keysOnly Whether to return only the keys,
* or return both the keys and values.
*
* @return ArrayObject An array with all matching keys as array keys,
* and values as array values. If $keysOnly is TRUE, the array keys are
* numeric, and the array values are key names.
*/
public function getIterator($filter = null, $keysOnly = false)
{
$info = wincache_ucache_info();
$result = array();
foreach ($info['ucache_entries'] as $entry) {
if (!$entry['is_session']
&& 0 === strpos($entry['key_name'], $this->persistentId)
) {
$localKey = strstr($entry['key_name'], $this->persistentId);
if (null === $filter || preg_match($filter, $localKey)) {
if ($keysOnly) {
$result[] = $localKey;
} else {
$result[$localKey] = apc_fetch($localKey);
}
}
}
}
return new ArrayObject($result);
}
}