/wp-content/plugins/accesspress-social-login-lite/google/Cache/File.php
PHP | 145 lines | 99 code | 17 blank | 29 comment | 15 complexity | 6babb7be303e8b300f08fd9768c35cd1 MD5 | raw file
- <?php
- /*
- * Copyright 2008 Google Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
- require_once APSL_PLUGIN_DIR."google/Cache/Abstract.php";
- require_once APSL_PLUGIN_DIR."google/Cache/Exception.php";
-
- /*
- * This class implements a basic on disk storage. While that does
- * work quite well it's not the most elegant and scalable solution.
- * It will also get you into a heap of trouble when you try to run
- * this in a clustered environment.
- *
- * @author Chris Chabot <chabotc@google.com>
- */
- class Google_Cache_File extends Google_Cache_Abstract
- {
- const MAX_LOCK_RETRIES = 10;
- private $path;
- private $fh;
-
- public function __construct(Google_Client $client)
- {
- $this->path = $client->getClassConfig($this, 'directory');
- }
-
- public function get($key, $expiration = false)
- {
- $storageFile = $this->getCacheFile($key);
- $data = false;
-
- if (!file_exists($storageFile)) {
- return false;
- }
-
- if ($expiration) {
- $mtime = filemtime($storageFile);
- if ((time() - $mtime) >= $expiration) {
- $this->delete($key);
- return false;
- }
- }
-
- if ($this->acquireReadLock($storageFile)) {
- $data = fread($this->fh, filesize($storageFile));
- $data = unserialize($data);
- $this->unlock($storageFile);
- }
-
- return $data;
- }
-
- public function set($key, $value)
- {
- $storageFile = $this->getWriteableCacheFile($key);
- if ($this->acquireWriteLock($storageFile)) {
- // We serialize the whole request object, since we don't only want the
- // responseContent but also the postBody used, headers, size, etc.
- $data = serialize($value);
- $result = fwrite($this->fh, $data);
- $this->unlock($storageFile);
- }
- }
-
- public function delete($key)
- {
- $file = $this->getCacheFile($key);
- if (file_exists($file) && !unlink($file)) {
- throw new Google_Cache_Exception("Cache file could not be deleted");
- }
- }
-
- private function getWriteableCacheFile($file)
- {
- return $this->getCacheFile($file, true);
- }
-
- private function getCacheFile($file, $forWrite = false)
- {
- return $this->getCacheDir($file, $forWrite) . '/' . md5($file);
- }
-
- private function getCacheDir($file, $forWrite)
- {
- // use the first 2 characters of the hash as a directory prefix
- // this should prevent slowdowns due to huge directory listings
- // and thus give some basic amount of scalability
- $storageDir = $this->path . '/' . substr(md5($file), 0, 2);
- if ($forWrite && ! is_dir($storageDir)) {
- if (! mkdir($storageDir, 0755, true)) {
- throw new Google_Cache_Exception("Could not create storage directory: $storageDir");
- }
- }
- return $storageDir;
- }
-
- private function acquireReadLock($storageFile)
- {
- return $this->acquireLock(LOCK_SH, $storageFile);
- }
-
- private function acquireWriteLock($storageFile)
- {
- $rc = $this->acquireLock(LOCK_EX, $storageFile);
- if (!$rc) {
- $this->delete($storageFile);
- }
- return $rc;
- }
-
- private function acquireLock($type, $storageFile)
- {
- $mode = $type == LOCK_EX ? "w" : "r";
- $this->fh = fopen($storageFile, $mode);
- $count = 0;
- while (!flock($this->fh, $type | LOCK_NB)) {
- // Sleep for 10ms.
- usleep(10000);
- if (++$count < self::MAX_LOCK_RETRIES) {
- return false;
- }
- }
- return true;
- }
-
- public function unlock($storageFile)
- {
- if ($this->fh) {
- flock($this->fh, LOCK_UN);
- }
- }
- }