316 lines
8.8 KiB
PHP
316 lines
8.8 KiB
PHP
|
<?php
|
||
|
|
/**
|
||
|
|
* @copyright Copyright (c) 2016, ownCloud, Inc.
|
||
|
|
*
|
||
|
|
* @author Christoph Wurst <christoph@winzerhof-wurst.at>
|
||
|
|
* @author Individual IT Services <info@individual-it.net>
|
||
|
|
* @author Joas Schilling <coding@schilljs.com>
|
||
|
|
* @author Lukas Reschke <lukas@statuscode.ch>
|
||
|
|
* @author Morris Jobke <hey@morrisjobke.de>
|
||
|
|
* @author Ole Ostergaard <ole.c.ostergaard@gmail.com>
|
||
|
|
* @author Robin Appelman <robin@icewind.nl>
|
||
|
|
* @author Roeland Jago Douma <roeland@famdouma.nl>
|
||
|
|
*
|
||
|
|
* @license AGPL-3.0
|
||
|
|
*
|
||
|
|
* This code is free software: you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU Affero General Public License, version 3,
|
||
|
|
* as published by the Free Software Foundation.
|
||
|
|
*
|
||
|
|
* This program is distributed in the hope that it will be useful,
|
||
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
* GNU Affero General Public License for more details.
|
||
|
|
*
|
||
|
|
* You should have received a copy of the GNU Affero General Public License, version 3,
|
||
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
namespace OC\Lock;
|
||
|
|
|
||
|
|
use OC\DB\QueryBuilder\Literal;
|
||
|
|
use OCP\AppFramework\Utility\ITimeFactory;
|
||
|
|
use OCP\DB\QueryBuilder\IQueryBuilder;
|
||
|
|
use OCP\IDBConnection;
|
||
|
|
use OCP\ILogger;
|
||
|
|
use OCP\Lock\ILockingProvider;
|
||
|
|
use OCP\Lock\LockedException;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Locking provider that stores the locks in the database
|
||
|
|
*/
|
||
|
|
class DBLockingProvider extends AbstractLockingProvider {
|
||
|
|
/**
|
||
|
|
* @var \OCP\IDBConnection
|
||
|
|
*/
|
||
|
|
private $connection;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @var \OCP\ILogger
|
||
|
|
*/
|
||
|
|
private $logger;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @var \OCP\AppFramework\Utility\ITimeFactory
|
||
|
|
*/
|
||
|
|
private $timeFactory;
|
||
|
|
|
||
|
|
private $sharedLocks = [];
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @var bool
|
||
|
|
*/
|
||
|
|
private $cacheSharedLocks;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if we have an open shared lock for a path
|
||
|
|
*
|
||
|
|
* @param string $path
|
||
|
|
* @return bool
|
||
|
|
*/
|
||
|
|
protected function isLocallyLocked(string $path): bool {
|
||
|
|
return isset($this->sharedLocks[$path]) && $this->sharedLocks[$path];
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Mark a locally acquired lock
|
||
|
|
*
|
||
|
|
* @param string $path
|
||
|
|
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
*/
|
||
|
|
protected function markAcquire(string $path, int $type) {
|
||
|
|
parent::markAcquire($path, $type);
|
||
|
|
if ($this->cacheSharedLocks) {
|
||
|
|
if ($type === self::LOCK_SHARED) {
|
||
|
|
$this->sharedLocks[$path] = true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Change the type of an existing tracked lock
|
||
|
|
*
|
||
|
|
* @param string $path
|
||
|
|
* @param int $targetType self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
*/
|
||
|
|
protected function markChange(string $path, int $targetType) {
|
||
|
|
parent::markChange($path, $targetType);
|
||
|
|
if ($this->cacheSharedLocks) {
|
||
|
|
if ($targetType === self::LOCK_SHARED) {
|
||
|
|
$this->sharedLocks[$path] = true;
|
||
|
|
} elseif ($targetType === self::LOCK_EXCLUSIVE) {
|
||
|
|
$this->sharedLocks[$path] = false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param \OCP\IDBConnection $connection
|
||
|
|
* @param \OCP\ILogger $logger
|
||
|
|
* @param \OCP\AppFramework\Utility\ITimeFactory $timeFactory
|
||
|
|
* @param int $ttl
|
||
|
|
* @param bool $cacheSharedLocks
|
||
|
|
*/
|
||
|
|
public function __construct(
|
||
|
|
IDBConnection $connection,
|
||
|
|
ILogger $logger,
|
||
|
|
ITimeFactory $timeFactory,
|
||
|
|
int $ttl = 3600,
|
||
|
|
$cacheSharedLocks = true
|
||
|
|
) {
|
||
|
|
$this->connection = $connection;
|
||
|
|
$this->logger = $logger;
|
||
|
|
$this->timeFactory = $timeFactory;
|
||
|
|
$this->ttl = $ttl;
|
||
|
|
$this->cacheSharedLocks = $cacheSharedLocks;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Insert a file locking row if it does not exists.
|
||
|
|
*
|
||
|
|
* @param string $path
|
||
|
|
* @param int $lock
|
||
|
|
* @return int number of inserted rows
|
||
|
|
*/
|
||
|
|
protected function initLockField(string $path, int $lock = 0): int {
|
||
|
|
$expire = $this->getExpireTime();
|
||
|
|
return $this->connection->insertIgnoreConflict('file_locks', [
|
||
|
|
'key' => $path,
|
||
|
|
'lock' => $lock,
|
||
|
|
'ttl' => $expire
|
||
|
|
]);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @return int
|
||
|
|
*/
|
||
|
|
protected function getExpireTime(): int {
|
||
|
|
return $this->timeFactory->getTime() + $this->ttl;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param string $path
|
||
|
|
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
* @return bool
|
||
|
|
*/
|
||
|
|
public function isLocked(string $path, int $type): bool {
|
||
|
|
if ($this->hasAcquiredLock($path, $type)) {
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
$query = $this->connection->prepare('SELECT `lock` from `*PREFIX*file_locks` WHERE `key` = ?');
|
||
|
|
$query->execute([$path]);
|
||
|
|
$lockValue = (int)$query->fetchColumn();
|
||
|
|
if ($type === self::LOCK_SHARED) {
|
||
|
|
if ($this->isLocallyLocked($path)) {
|
||
|
|
// if we have a shared lock we kept open locally but it's released we always have at least 1 shared lock in the db
|
||
|
|
return $lockValue > 1;
|
||
|
|
} else {
|
||
|
|
return $lockValue > 0;
|
||
|
|
}
|
||
|
|
} elseif ($type === self::LOCK_EXCLUSIVE) {
|
||
|
|
return $lockValue === -1;
|
||
|
|
} else {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param string $path
|
||
|
|
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
* @throws \OCP\Lock\LockedException
|
||
|
|
*/
|
||
|
|
public function acquireLock(string $path, int $type, string $readablePath = null) {
|
||
|
|
$expire = $this->getExpireTime();
|
||
|
|
if ($type === self::LOCK_SHARED) {
|
||
|
|
if (!$this->isLocallyLocked($path)) {
|
||
|
|
$result = $this->initLockField($path, 1);
|
||
|
|
if ($result <= 0) {
|
||
|
|
$result = $this->connection->executeUpdate(
|
||
|
|
'UPDATE `*PREFIX*file_locks` SET `lock` = `lock` + 1, `ttl` = ? WHERE `key` = ? AND `lock` >= 0',
|
||
|
|
[$expire, $path]
|
||
|
|
);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
$result = 1;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
$existing = 0;
|
||
|
|
if ($this->hasAcquiredLock($path, ILockingProvider::LOCK_SHARED) === false && $this->isLocallyLocked($path)) {
|
||
|
|
$existing = 1;
|
||
|
|
}
|
||
|
|
$result = $this->initLockField($path, -1);
|
||
|
|
if ($result <= 0) {
|
||
|
|
$result = $this->connection->executeUpdate(
|
||
|
|
'UPDATE `*PREFIX*file_locks` SET `lock` = -1, `ttl` = ? WHERE `key` = ? AND `lock` = ?',
|
||
|
|
[$expire, $path, $existing]
|
||
|
|
);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if ($result !== 1) {
|
||
|
|
throw new LockedException($path, null, null, $readablePath);
|
||
|
|
}
|
||
|
|
$this->markAcquire($path, $type);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @param string $path
|
||
|
|
* @param int $type self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
*/
|
||
|
|
public function releaseLock(string $path, int $type) {
|
||
|
|
$this->markRelease($path, $type);
|
||
|
|
|
||
|
|
// we keep shared locks till the end of the request so we can re-use them
|
||
|
|
if ($type === self::LOCK_EXCLUSIVE) {
|
||
|
|
$this->connection->executeUpdate(
|
||
|
|
'UPDATE `*PREFIX*file_locks` SET `lock` = 0 WHERE `key` = ? AND `lock` = -1',
|
||
|
|
[$path]
|
||
|
|
);
|
||
|
|
} elseif (!$this->cacheSharedLocks) {
|
||
|
|
$query = $this->connection->getQueryBuilder();
|
||
|
|
$query->update('file_locks')
|
||
|
|
->set('lock', $query->func()->subtract('lock', $query->createNamedParameter(1)))
|
||
|
|
->where($query->expr()->eq('key', $query->createNamedParameter($path)))
|
||
|
|
->andWhere($query->expr()->gt('lock', $query->createNamedParameter(0)));
|
||
|
|
$query->execute();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Change the type of an existing lock
|
||
|
|
*
|
||
|
|
* @param string $path
|
||
|
|
* @param int $targetType self::LOCK_SHARED or self::LOCK_EXCLUSIVE
|
||
|
|
* @throws \OCP\Lock\LockedException
|
||
|
|
*/
|
||
|
|
public function changeLock(string $path, int $targetType) {
|
||
|
|
$expire = $this->getExpireTime();
|
||
|
|
if ($targetType === self::LOCK_SHARED) {
|
||
|
|
$result = $this->connection->executeUpdate(
|
||
|
|
'UPDATE `*PREFIX*file_locks` SET `lock` = 1, `ttl` = ? WHERE `key` = ? AND `lock` = -1',
|
||
|
|
[$expire, $path]
|
||
|
|
);
|
||
|
|
} else {
|
||
|
|
// since we only keep one shared lock in the db we need to check if we have more then one shared lock locally manually
|
||
|
|
if (isset($this->acquiredLocks['shared'][$path]) && $this->acquiredLocks['shared'][$path] > 1) {
|
||
|
|
throw new LockedException($path);
|
||
|
|
}
|
||
|
|
$result = $this->connection->executeUpdate(
|
||
|
|
'UPDATE `*PREFIX*file_locks` SET `lock` = -1, `ttl` = ? WHERE `key` = ? AND `lock` = 1',
|
||
|
|
[$expire, $path]
|
||
|
|
);
|
||
|
|
}
|
||
|
|
if ($result !== 1) {
|
||
|
|
throw new LockedException($path);
|
||
|
|
}
|
||
|
|
$this->markChange($path, $targetType);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* cleanup empty locks
|
||
|
|
*/
|
||
|
|
public function cleanExpiredLocks() {
|
||
|
|
$expire = $this->timeFactory->getTime();
|
||
|
|
try {
|
||
|
|
$this->connection->executeUpdate(
|
||
|
|
'DELETE FROM `*PREFIX*file_locks` WHERE `ttl` < ?',
|
||
|
|
[$expire]
|
||
|
|
);
|
||
|
|
} catch (\Exception $e) {
|
||
|
|
// If the table is missing, the clean up was successful
|
||
|
|
if ($this->connection->tableExists('file_locks')) {
|
||
|
|
throw $e;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* release all lock acquired by this instance which were marked using the mark* methods
|
||
|
|
*/
|
||
|
|
public function releaseAll() {
|
||
|
|
parent::releaseAll();
|
||
|
|
|
||
|
|
if (!$this->cacheSharedLocks) {
|
||
|
|
return;
|
||
|
|
}
|
||
|
|
// since we keep shared locks we need to manually clean those
|
||
|
|
$lockedPaths = array_keys($this->sharedLocks);
|
||
|
|
$lockedPaths = array_filter($lockedPaths, function ($path) {
|
||
|
|
return $this->sharedLocks[$path];
|
||
|
|
});
|
||
|
|
|
||
|
|
$chunkedPaths = array_chunk($lockedPaths, 100);
|
||
|
|
|
||
|
|
foreach ($chunkedPaths as $chunk) {
|
||
|
|
$builder = $this->connection->getQueryBuilder();
|
||
|
|
|
||
|
|
$query = $builder->update('file_locks')
|
||
|
|
->set('lock', $builder->func()->subtract('lock', $builder->expr()->literal(1)))
|
||
|
|
->where($builder->expr()->in('key', $builder->createNamedParameter($chunk, IQueryBuilder::PARAM_STR_ARRAY)))
|
||
|
|
->andWhere($builder->expr()->gt('lock', new Literal(0)));
|
||
|
|
|
||
|
|
$query->execute();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|