From 04d6d5ca99ebfd1cebb8ce06618fb3811fc1a8aa Mon Sep 17 00:00:00 2001 From: Charles Date: Thu, 9 Jan 2020 10:55:03 +0100 Subject: phpmyadmin working --- .../vendor/symfony/cache/LockRegistry.php | 154 +++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 srcs/phpmyadmin/vendor/symfony/cache/LockRegistry.php (limited to 'srcs/phpmyadmin/vendor/symfony/cache/LockRegistry.php') diff --git a/srcs/phpmyadmin/vendor/symfony/cache/LockRegistry.php b/srcs/phpmyadmin/vendor/symfony/cache/LockRegistry.php new file mode 100644 index 0000000..80601be --- /dev/null +++ b/srcs/phpmyadmin/vendor/symfony/cache/LockRegistry.php @@ -0,0 +1,154 @@ + + * + * For the full copyright and license information, please view the LICENSE + * file that was distributed with this source code. + */ + +namespace Symfony\Component\Cache; + +use Psr\Log\LoggerInterface; +use Symfony\Contracts\Cache\CacheInterface; +use Symfony\Contracts\Cache\ItemInterface; + +/** + * LockRegistry is used internally by existing adapters to protect against cache stampede. + * + * It does so by wrapping the computation of items in a pool of locks. + * Foreach each apps, there can be at most 20 concurrent processes that + * compute items at the same time and only one per cache-key. + * + * @author Nicolas Grekas + */ +final class LockRegistry +{ + private static $openedFiles = []; + private static $lockedFiles = []; + + /** + * The number of items in this list controls the max number of concurrent processes. + */ + private static $files = [ + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'AbstractAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'AbstractTagAwareAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'AdapterInterface.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'ApcuAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'ArrayAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'ChainAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'DoctrineAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'FilesystemAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'FilesystemTagAwareAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'MemcachedAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'NullAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'PdoAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'PhpArrayAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'PhpFilesAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'ProxyAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'Psr16Adapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'RedisAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'RedisTagAwareAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'SimpleCacheAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'TagAwareAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'TagAwareAdapterInterface.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'TraceableAdapter.php', + __DIR__.\DIRECTORY_SEPARATOR.'Adapter'.\DIRECTORY_SEPARATOR.'TraceableTagAwareAdapter.php', + ]; + + /** + * Defines a set of existing files that will be used as keys to acquire locks. + * + * @return array The previously defined set of files + */ + public static function setFiles(array $files): array + { + $previousFiles = self::$files; + self::$files = $files; + + foreach (self::$openedFiles as $file) { + if ($file) { + flock($file, LOCK_UN); + fclose($file); + } + } + self::$openedFiles = self::$lockedFiles = []; + + return $previousFiles; + } + + public static function compute(callable $callback, ItemInterface $item, bool &$save, CacheInterface $pool, \Closure $setMetadata = null, LoggerInterface $logger = null) + { + $key = self::$files ? crc32($item->getKey()) % \count(self::$files) : -1; + + if ($key < 0 || (self::$lockedFiles[$key] ?? false) || !$lock = self::open($key)) { + return $callback($item, $save); + } + + while (true) { + try { + // race to get the lock in non-blocking mode + $locked = flock($lock, LOCK_EX | LOCK_NB, $wouldBlock); + + if ($locked || !$wouldBlock) { + $logger && $logger->info(sprintf('Lock %s, now computing item "{key}"', $locked ? 'acquired' : 'not supported'), ['key' => $item->getKey()]); + self::$lockedFiles[$key] = true; + + $value = $callback($item, $save); + + if ($save) { + if ($setMetadata) { + $setMetadata($item); + } + + $pool->save($item->set($value)); + $save = false; + } + + return $value; + } + // if we failed the race, retry locking in blocking mode to wait for the winner + $logger && $logger->info('Item "{key}" is locked, waiting for it to be released', ['key' => $item->getKey()]); + flock($lock, LOCK_SH); + } finally { + flock($lock, LOCK_UN); + unset(self::$lockedFiles[$key]); + } + static $signalingException, $signalingCallback; + $signalingException = $signalingException ?? unserialize("O:9:\"Exception\":1:{s:16:\"\0Exception\0trace\";a:0:{}}"); + $signalingCallback = $signalingCallback ?? function () use ($signalingException) { throw $signalingException; }; + + try { + $value = $pool->get($item->getKey(), $signalingCallback, 0); + $logger && $logger->info('Item "{key}" retrieved after lock was released', ['key' => $item->getKey()]); + $save = false; + + return $value; + } catch (\Exception $e) { + if ($signalingException !== $e) { + throw $e; + } + $logger && $logger->info('Item "{key}" not found while lock was released, now retrying', ['key' => $item->getKey()]); + } + } + + return null; + } + + private static function open(int $key) + { + if (null !== $h = self::$openedFiles[$key] ?? null) { + return $h; + } + set_error_handler(function () {}); + try { + $h = fopen(self::$files[$key], 'r+'); + } finally { + restore_error_handler(); + } + + return self::$openedFiles[$key] = $h ?: @fopen(self::$files[$key], 'r'); + } +} -- cgit