Subversion Repositories SmartDukaan

<?php

/**

 * File Storage engine for cache. Filestorage is the slowest cache storage

 * to read and write. However, it is good for servers that don't have other storage

 * engine available, or have content which is not performance sensitive.

 *

 * You can configure a FileEngine cache, using Cache::config()

 *

 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)

 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 *

 * Licensed under The MIT License

 * For full copyright and license information, please see the LICENSE.txt

 * Redistributions of files must retain the above copyright notice.

 *

 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 * @link          http://cakephp.org CakePHP(tm) Project

 * @since         CakePHP(tm) v 1.2.0.4933

 * @license       http://www.opensource.org/licenses/mit-license.php MIT License

 */

/**

 * File Storage engine for cache. Filestorage is the slowest cache storage

 * to read and write. However, it is good for servers that don't have other storage

 * engine available, or have content which is not performance sensitive.

 *

 * You can configure a FileEngine cache, using Cache::config()

 *

 * @package       Cake.Cache.Engine

 */

class FileEngine extends CacheEngine {

/**

 * Instance of SplFileObject class

 *

 * @var File

 */

	protected $_File = null;

/**

 * Settings

 *

 * - path = absolute path to cache directory, default => CACHE

 * - prefix = string prefix for filename, default => cake_

 * - lock = enable file locking on write, default => true

 * - serialize = serialize the data, default => true

 *

 * @var array

 * @see CacheEngine::__defaults

 */

	public $settings = array();

/**

 * True unless FileEngine::__active(); fails

 *

 * @var bool

 */

	protected $_init = true;

/**

 * Initialize the Cache Engine

 *

 * Called automatically by the cache frontend

 * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());

 *

 * @param array $settings array of setting for the engine

 * @return bool True if the engine has been successfully initialized, false if not

 */

	public function init($settings = array()) {

		$settings += array(

			'engine' => 'File',

			'path' => CACHE,

			'prefix' => 'cake_',

			'lock' => true,

			'serialize' => true,

			'isWindows' => false,

			'mask' => 0664

		);

		parent::init($settings);

		if (DS === '\\') {

			$this->settings['isWindows'] = true;

		}

		if (substr($this->settings['path'], -1) !== DS) {

			$this->settings['path'] .= DS;

		}

		if (!empty($this->_groupPrefix)) {

			$this->_groupPrefix = str_replace('_', DS, $this->_groupPrefix);

		}

		return $this->_active();

	}

/**

 * Garbage collection. Permanently remove all expired and deleted data

 *

 * @param int $expires [optional] An expires timestamp, invalidating all data before.

 * @return bool True if garbage collection was successful, false on failure

 */

	public function gc($expires = null) {

		return $this->clear(true);

	}

/**

 * Write data for key into cache

 *

 * @param string $key Identifier for the data

 * @param mixed $data Data to be cached

 * @param int $duration How long to cache the data, in seconds

 * @return bool True if the data was successfully cached, false on failure

 */

	public function write($key, $data, $duration) {

		if ($data === '' || !$this->_init) {

			return false;

		}

		if ($this->_setKey($key, true) === false) {

			return false;

		}

		$lineBreak = "\n";

		if ($this->settings['isWindows']) {

			$lineBreak = "\r\n";

		}

		if (!empty($this->settings['serialize'])) {

			if ($this->settings['isWindows']) {

				$data = str_replace('\\', '\\\\\\\\', serialize($data));

			} else {

				$data = serialize($data);

			}

		}

		$expires = time() + $duration;

		$contents = $expires . $lineBreak . $data . $lineBreak;

		if ($this->settings['lock']) {

			$this->_File->flock(LOCK_EX);

		}

		$this->_File->rewind();

		$success = $this->_File->ftruncate(0) && $this->_File->fwrite($contents) && $this->_File->fflush();

		if ($this->settings['lock']) {

			$this->_File->flock(LOCK_UN);

		}

		return $success;

	}

/**

 * Read a key from the cache

 *

 * @param string $key Identifier for the data

 * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it

 */

	public function read($key) {

		if (!$this->_init || $this->_setKey($key) === false) {

			return false;

		}

		if ($this->settings['lock']) {

			$this->_File->flock(LOCK_SH);

		}

		$this->_File->rewind();

		$time = time();

		$cachetime = (int)$this->_File->current();

		if ($cachetime !== false && ($cachetime < $time || ($time + $this->settings['duration']) < $cachetime)) {

			if ($this->settings['lock']) {

				$this->_File->flock(LOCK_UN);

			}

			return false;

		}

		$data = '';

		$this->_File->next();

		while ($this->_File->valid()) {

			$data .= $this->_File->current();

			$this->_File->next();

		}

		if ($this->settings['lock']) {

			$this->_File->flock(LOCK_UN);

		}

		$data = trim($data);

		if ($data !== '' && !empty($this->settings['serialize'])) {

			if ($this->settings['isWindows']) {

				$data = str_replace('\\\\\\\\', '\\', $data);

			}

			$data = unserialize((string)$data);

		}

		return $data;

	}

/**

 * Delete a key from the cache

 *

 * @param string $key Identifier for the data

 * @return bool True if the value was successfully deleted, false if it didn't exist or couldn't be removed

 */

	public function delete($key) {

		if ($this->_setKey($key) === false || !$this->_init) {

			return false;

		}

		$path = $this->_File->getRealPath();

		$this->_File = null;

		//@codingStandardsIgnoreStart

		return @unlink($path);

		//@codingStandardsIgnoreEnd

	}

/**

 * Delete all values from the cache

 *

 * @param bool $check Optional - only delete expired cache items

 * @return bool True if the cache was successfully cleared, false otherwise

 */

	public function clear($check) {

		if (!$this->_init) {

			return false;

		}

		$this->_File = null;

		$threshold = $now = false;

		if ($check) {

			$now = time();

			$threshold = $now - $this->settings['duration'];

		}

		$this->_clearDirectory($this->settings['path'], $now, $threshold);

		$directory = new RecursiveDirectoryIterator($this->settings['path']);

		$contents = new RecursiveIteratorIterator($directory, RecursiveIteratorIterator::SELF_FIRST);

		$cleared = array();

		foreach ($contents as $path) {

			if ($path->isFile()) {

				continue;

			}

			$path = $path->getRealPath() . DS;

			if (!in_array($path, $cleared)) {

				$this->_clearDirectory($path, $now, $threshold);

				$cleared[] = $path;

			}

		}

		return true;

	}

/**

 * Used to clear a directory of matching files.

 *

 * @param string $path The path to search.

 * @param int $now The current timestamp

 * @param int $threshold Any file not modified after this value will be deleted.

 * @return void

 */

	protected function _clearDirectory($path, $now, $threshold) {

		$prefixLength = strlen($this->settings['prefix']);

		if (!is_dir($path)) {

			return;

		}

		$dir = dir($path);

		while (($entry = $dir->read()) !== false) {

			if (substr($entry, 0, $prefixLength) !== $this->settings['prefix']) {

				continue;

			}

			try {

				$file = new SplFileObject($path . $entry, 'r');

			} catch (Exception $e) {

				continue;

			}

			if ($threshold) {

				$mtime = $file->getMTime();

				if ($mtime > $threshold) {

					continue;

				}

				$expires = (int)$file->current();

				if ($expires > $now) {

					continue;

				}

			}

			if ($file->isFile()) {

				$filePath = $file->getRealPath();

				$file = null;

				//@codingStandardsIgnoreStart

				@unlink($filePath);

				//@codingStandardsIgnoreEnd

			}

		}

	}

/**

 * Not implemented

 *

 * @param string $key The key to decrement

 * @param int $offset The number to offset

 * @return void

 * @throws CacheException

 */

	public function decrement($key, $offset = 1) {

		throw new CacheException(__d('cake_dev', 'Files cannot be atomically decremented.'));

	}

/**

 * Not implemented

 *

 * @param string $key The key to decrement

 * @param int $offset The number to offset

 * @return void

 * @throws CacheException

 */

	public function increment($key, $offset = 1) {

		throw new CacheException(__d('cake_dev', 'Files cannot be atomically incremented.'));

	}

/**

 * Sets the current cache key this class is managing, and creates a writable SplFileObject

 * for the cache file the key is referring to.

 *

 * @param string $key The key

 * @param bool $createKey Whether the key should be created if it doesn't exists, or not

 * @return bool true if the cache key could be set, false otherwise

 */

	protected function _setKey($key, $createKey = false) {

		$groups = null;

		if (!empty($this->_groupPrefix)) {

			$groups = vsprintf($this->_groupPrefix, $this->groups());

		}

		$dir = $this->settings['path'] . $groups;

		if (!is_dir($dir)) {

			mkdir($dir, 0775, true);

		}

		$path = new SplFileInfo($dir . $key);

		if (!$createKey && !$path->isFile()) {

			return false;

		}

		if (empty($this->_File) || $this->_File->getBaseName() !== $key) {

			$exists = file_exists($path->getPathname());

			try {

				$this->_File = $path->openFile('c+');

			} catch (Exception $e) {

				trigger_error($e->getMessage(), E_USER_WARNING);

				return false;

			}

			unset($path);

			if (!$exists && !chmod($this->_File->getPathname(), (int)$this->settings['mask'])) {

				trigger_error(__d(

					'cake_dev', 'Could not apply permission mask "%s" on cache file "%s"',

					array($this->_File->getPathname(), $this->settings['mask'])), E_USER_WARNING);

			}

		}

		return true;

	}

/**

 * Determine is cache directory is writable

 *

 * @return bool

 */

	protected function _active() {

		$dir = new SplFileInfo($this->settings['path']);

		if (Configure::read('debug')) {

			$path = $dir->getPathname();

			if (!is_dir($path)) {

				mkdir($path, 0775, true);

			}

		}

		if ($this->_init && !($dir->isDir() && $dir->isWritable())) {

			$this->_init = false;

			trigger_error(__d('cake_dev', '%s is not writable', $this->settings['path']), E_USER_WARNING);

			return false;

		}

		return true;

	}

/**

 * Generates a safe key for use with cache engine storage engines.

 *

 * @param string $key the key passed over

 * @return mixed string $key or false

 */

	public function key($key) {

		if (empty($key)) {

			return false;

		}

		$key = Inflector::underscore(str_replace(array(DS, '/', '.', '<', '>', '?', ':', '|', '*', '"'), '_', strval($key)));

		return $key;

	}

/**

 * Recursively deletes all files under any directory named as $group

 *

 * @param string $group The group to clear.

 * @return bool success

 */

	public function clearGroup($group) {

		$this->_File = null;

		$directoryIterator = new RecursiveDirectoryIterator($this->settings['path']);

		$contents = new RecursiveIteratorIterator($directoryIterator, RecursiveIteratorIterator::CHILD_FIRST);

		foreach ($contents as $object) {

			$containsGroup = strpos($object->getPathName(), DS . $group . DS) !== false;

			$hasPrefix = true;

			if (strlen($this->settings['prefix']) !== 0) {

				$hasPrefix = strpos($object->getBaseName(), $this->settings['prefix']) === 0;

			}

			if ($object->isFile() && $containsGroup && $hasPrefix) {

				$path = $object->getPathName();

				$object = null;

				//@codingStandardsIgnoreStart

				@unlink($path);

				//@codingStandardsIgnoreEnd

			}

		}

		return true;

	}

}