%PDF-
%PDF-
Mini Shell
Mini Shell
<?php
/**
* This file is part of the Nette Framework (http://nette.org)
*
* Copyright (c) 2004 David Grudl (http://davidgrudl.com)
*
* For the full copyright and license information, please view
* the file license.txt that was distributed with this source code.
*/
namespace Nette\Caching\Storages;
use Nette,
Nette\Caching\Cache;
/**
* Cache file storage.
*
* @author David Grudl
*/
class FileStorage extends Nette\Object implements Nette\Caching\IStorage
{
/**
* Atomic thread safe logic:
*
* 1) reading: open(r+b), lock(SH), read
* - delete?: delete*, close
* 2) deleting: delete*
* 3) writing: open(r+b || wb), lock(EX), truncate*, write data, write meta, close
*
* delete* = try unlink, if fails (on NTFS) { lock(EX), truncate, close, unlink } else close (on ext3)
*/
/** @internal cache file structure */
const META_HEADER_LEN = 28, // 22b signature + 6b meta-struct size + serialized meta-struct + data
// meta structure: array of
META_TIME = 'time', // timestamp
META_SERIALIZED = 'serialized', // is content serialized?
META_EXPIRE = 'expire', // expiration timestamp
META_DELTA = 'delta', // relative (sliding) expiration
META_ITEMS = 'di', // array of dependent items (file => timestamp)
META_CALLBACKS = 'callbacks'; // array of callbacks (function, args)
/** additional cache structure */
const FILE = 'file',
HANDLE = 'handle';
/** @var float probability that the clean() routine is started */
public static $gcProbability = 0.001;
/** @var bool */
public static $useDirectories = TRUE;
/** @var string */
private $dir;
/** @var bool */
private $useDirs;
/** @var IJournal */
private $journal;
/** @var array */
private $locks;
public function __construct($dir, IJournal $journal = NULL)
{
$this->dir = realpath($dir);
if ($this->dir === FALSE) {
throw new Nette\DirectoryNotFoundException("Directory '$dir' not found.");
}
$this->useDirs = (bool) static::$useDirectories;
$this->journal = $journal;
if (mt_rand() / mt_getrandmax() < static::$gcProbability) {
$this->clean(array());
}
}
/**
* Read from cache.
* @param string key
* @return mixed|NULL
*/
public function read($key)
{
$meta = $this->readMetaAndLock($this->getCacheFile($key), LOCK_SH);
if ($meta && $this->verify($meta)) {
return $this->readData($meta); // calls fclose()
} else {
return NULL;
}
}
/**
* Verifies dependencies.
* @param array
* @return bool
*/
private function verify($meta)
{
do {
if (!empty($meta[self::META_DELTA])) {
// meta[file] was added by readMetaAndLock()
if (filemtime($meta[self::FILE]) + $meta[self::META_DELTA] < time()) {
break;
}
touch($meta[self::FILE]);
} elseif (!empty($meta[self::META_EXPIRE]) && $meta[self::META_EXPIRE] < time()) {
break;
}
if (!empty($meta[self::META_CALLBACKS]) && !Cache::checkCallbacks($meta[self::META_CALLBACKS])) {
break;
}
if (!empty($meta[self::META_ITEMS])) {
foreach ($meta[self::META_ITEMS] as $depFile => $time) {
$m = $this->readMetaAndLock($depFile, LOCK_SH);
if ($m[self::META_TIME] !== $time || ($m && !$this->verify($m))) {
break 2;
}
}
}
return TRUE;
} while (FALSE);
$this->delete($meta[self::FILE], $meta[self::HANDLE]); // meta[handle] & meta[file] was added by readMetaAndLock()
return FALSE;
}
/**
* Prevents item reading and writing. Lock is released by write() or remove().
* @param string key
* @return void
*/
public function lock($key)
{
$cacheFile = $this->getCacheFile($key);
if ($this->useDirs && !is_dir($dir = dirname($cacheFile))) {
@mkdir($dir); // @ - directory may already exist
}
$handle = @fopen($cacheFile, 'r+b'); // @ - file may not exist
if (!$handle) {
$handle = fopen($cacheFile, 'wb');
if (!$handle) {
return;
}
}
$this->locks[$key] = $handle;
flock($handle, LOCK_EX);
}
/**
* Writes item into the cache.
* @param string key
* @param mixed data
* @param array dependencies
* @return void
*/
public function write($key, $data, array $dp)
{
$meta = array(
self::META_TIME => microtime(),
);
if (isset($dp[Cache::EXPIRATION])) {
if (empty($dp[Cache::SLIDING])) {
$meta[self::META_EXPIRE] = $dp[Cache::EXPIRATION] + time(); // absolute time
} else {
$meta[self::META_DELTA] = (int) $dp[Cache::EXPIRATION]; // sliding time
}
}
if (isset($dp[Cache::ITEMS])) {
foreach ((array) $dp[Cache::ITEMS] as $item) {
$depFile = $this->getCacheFile($item);
$m = $this->readMetaAndLock($depFile, LOCK_SH);
$meta[self::META_ITEMS][$depFile] = $m[self::META_TIME]; // may be NULL
unset($m);
}
}
if (isset($dp[Cache::CALLBACKS])) {
$meta[self::META_CALLBACKS] = $dp[Cache::CALLBACKS];
}
if (!isset($this->locks[$key])) {
$this->lock($key);
if (!isset($this->locks[$key])) {
return;
}
}
$handle = $this->locks[$key];
unset($this->locks[$key]);
$cacheFile = $this->getCacheFile($key);
if (isset($dp[Cache::TAGS]) || isset($dp[Cache::PRIORITY])) {
if (!$this->journal) {
throw new Nette\InvalidStateException('CacheJournal has not been provided.');
}
$this->journal->write($cacheFile, $dp);
}
ftruncate($handle, 0);
if (!is_string($data)) {
$data = serialize($data);
$meta[self::META_SERIALIZED] = TRUE;
}
$head = serialize($meta) . '?>';
$head = '<?php //netteCache[01]' . str_pad((string) strlen($head), 6, '0', STR_PAD_LEFT) . $head;
$headLen = strlen($head);
$dataLen = strlen($data);
do {
if (fwrite($handle, str_repeat("\x00", $headLen), $headLen) !== $headLen) {
break;
}
if (fwrite($handle, $data, $dataLen) !== $dataLen) {
break;
}
fseek($handle, 0);
if (fwrite($handle, $head, $headLen) !== $headLen) {
break;
}
flock($handle, LOCK_UN);
fclose($handle);
return;
} while (FALSE);
$this->delete($cacheFile, $handle);
}
/**
* Removes item from the cache.
* @param string key
* @return void
*/
public function remove($key)
{
unset($this->locks[$key]);
$this->delete($this->getCacheFile($key));
}
/**
* Removes items from the cache by conditions & garbage collector.
* @param array conditions
* @return void
*/
public function clean(array $conditions)
{
$all = !empty($conditions[Cache::ALL]);
$collector = empty($conditions);
// cleaning using file iterator
if ($all || $collector) {
$now = time();
foreach (Nette\Utils\Finder::find('_*')->from($this->dir)->childFirst() as $entry) {
$path = (string) $entry;
if ($entry->isDir()) { // collector: remove empty dirs
@rmdir($path); // @ - removing dirs is not necessary
continue;
}
if ($all) {
$this->delete($path);
} else { // collector
$meta = $this->readMetaAndLock($path, LOCK_SH);
if (!$meta) {
continue;
}
if ((!empty($meta[self::META_DELTA]) && filemtime($meta[self::FILE]) + $meta[self::META_DELTA] < $now)
|| (!empty($meta[self::META_EXPIRE]) && $meta[self::META_EXPIRE] < $now)
) {
$this->delete($path, $meta[self::HANDLE]);
continue;
}
flock($meta[self::HANDLE], LOCK_UN);
fclose($meta[self::HANDLE]);
}
}
if ($this->journal) {
$this->journal->clean($conditions);
}
return;
}
// cleaning using journal
if ($this->journal) {
foreach ($this->journal->clean($conditions) as $file) {
$this->delete($file);
}
}
}
/**
* Reads cache data from disk.
* @param string file path
* @param int lock mode
* @return array|NULL
*/
protected function readMetaAndLock($file, $lock)
{
$handle = @fopen($file, 'r+b'); // @ - file may not exist
if (!$handle) {
return NULL;
}
flock($handle, $lock);
$head = stream_get_contents($handle, self::META_HEADER_LEN);
if ($head && strlen($head) === self::META_HEADER_LEN) {
$size = (int) substr($head, -6);
$meta = stream_get_contents($handle, $size, self::META_HEADER_LEN);
$meta = @unserialize($meta); // intentionally @
if (is_array($meta)) {
fseek($handle, $size + self::META_HEADER_LEN); // needed by PHP < 5.2.6
$meta[self::FILE] = $file;
$meta[self::HANDLE] = $handle;
return $meta;
}
}
flock($handle, LOCK_UN);
fclose($handle);
return NULL;
}
/**
* Reads cache data from disk and closes cache file handle.
* @param array
* @return mixed
*/
protected function readData($meta)
{
$data = stream_get_contents($meta[self::HANDLE]);
flock($meta[self::HANDLE], LOCK_UN);
fclose($meta[self::HANDLE]);
if (empty($meta[self::META_SERIALIZED])) {
return $data;
} else {
return @unserialize($data); // intentionally @
}
}
/**
* Returns file name.
* @param string
* @return string
*/
protected function getCacheFile($key)
{
$file = urlencode($key);
if ($this->useDirs && $a = strrpos($file, '%00')) { // %00 = urlencode(Nette\Caching\Cache::NAMESPACE_SEPARATOR)
$file = substr_replace($file, '/_', $a, 3);
}
return $this->dir . '/_' . $file;
}
/**
* Deletes and closes file.
* @param string
* @param resource
* @return void
*/
private static function delete($file, $handle = NULL)
{
if (@unlink($file)) { // @ - file may not already exist
if ($handle) {
flock($handle, LOCK_UN);
fclose($handle);
}
return;
}
if (!$handle) {
$handle = @fopen($file, 'r+'); // @ - file may not exist
}
if ($handle) {
flock($handle, LOCK_EX);
ftruncate($handle, 0);
flock($handle, LOCK_UN);
fclose($handle);
@unlink($file); // @ - file may not already exist
}
}
}
Zerion Mini Shell 1.0