owncloud/core

<?php
/**
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Robin Appelman <icewind@owncloud.com>
 * @author Thomas Müller <thomas.mueller@tmit.eu>
 *
 * @copyright Copyright (c) 2018, ownCloud GmbH
 * @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\Files\Config;

use OC\Files\Filesystem;
use OC\Files\Mount\MountPoint;
use OC\Files\View;
use OC\Hooks\Emitter;
use OC\Hooks\EmitterTrait;
use OCP\Files\Config\IHomeMountProvider;
use OCP\Files\Config\IMountProviderCollection;
use OCP\Files\Config\IMountProvider;
use OCP\Files\Config\IUserMountCache;
use OCP\Files\Mount\IMountPoint;
use OCP\Files\Storage\IStorageFactory;
use OCP\IUser;

class MountProviderCollection implements IMountProviderCollection, Emitter {
    use EmitterTrait;

    public const DEFAULT_MOVE_ATTEMPTS_PER_MOUNTPOINT = 10;

    /**
     * @var \OCP\Files\Config\IHomeMountProvider[]
     */
    private $homeProviders = [];

    /**
     * @var \OCP\Files\Config\IMountProvider[]
     */
    private $providers = [];

    /**
     * @var \OCP\Files\Storage\IStorageFactory
     */
    private $loader;

    /**
     * @var \OCP\Files\Config\IUserMountCache
     */
    private $mountCache;

    /**
     * @param \OCP\Files\Storage\IStorageFactory $loader
     * @param IUserMountCache $mountCache
     */
    public function __construct(IStorageFactory $loader, IUserMountCache $mountCache) {
        $this->loader = $loader;
        $this->mountCache = $mountCache;
    }

    /**
     * Get all configured mount points for the user
     *
     * @param \OCP\IUser $user
     * @return \OCP\Files\Mount\IMountPoint[]
     */
    public function getMountsForUser(IUser $user) {
        $loader = $this->loader;
        $mounts = \array_map(function (IMountProvider $provider) use ($user, $loader) {
            return $provider->getMountsForUser($user, $loader);
        }, $this->providers);
        $mounts = \array_filter($mounts, function ($result) {
            return \is_array($result);
        });

        $mergedMounts = [];
        $takenMountpoints = [];
        $maxMoveAttempts = $this->getMaxMoveAttempts();
        foreach ($mounts as $providerMounts) {
            foreach ($providerMounts as $mount) {
                $mountpoint = $mount->getMountPoint();
                if (\in_array($mountpoint, $takenMountpoints)) {
                    for ($i = 0; $i < $maxMoveAttempts; $i++) {
                        $newMountpoint = $this->generateUniqueTarget(
                            $mountpoint,
                            new View('/' . $user->getUID() . '/files'),
                            $takenMountpoints
                        );
                        /* @phan-suppress-next-line PhanUndeclaredMethod */
                        if ($mount->moveMount($newMountpoint) === true) {
                            $fsMountManager = Filesystem::getMountManager();
                            if ($fsMountManager->findIn($mountpoint)) {
                                $fsMountManager->moveMount($mountpoint, $newMountpoint);
                            }
                            break;
                        }
                        $takenMountpoints[] = $newMountpoint;
                    }
                    $takenMountpoints[] = $mount->getMountPoint(); // mount might not have been moved
                } else {
                    $takenMountpoints[] = $mountpoint;
                }
                $mergedMounts[] = $mount;
            }
        }

        return $mergedMounts;
    }

    /**
     * Get the configured home mount for this user
     *
     * @param \OCP\IUser $user
     * @return \OCP\Files\Mount\IMountPoint
     * @since 9.1.0
     */
    public function getHomeMountForUser(IUser $user) {
        /** @var \OCP\Files\Config\IHomeMountProvider[] $providers */
        $providers = \array_reverse($this->homeProviders); // call the latest registered provider first to give apps an opportunity to overwrite builtin
        foreach ($providers as $homeProvider) {
            if ($mount = $homeProvider->getHomeMountForUser($user, $this->loader)) {
                $mount->setMountPoint('/' . $user->getUID()); //make sure the mountpoint is what we expect
                return $mount;
            }
        }
        throw new \Exception('No home storage configured for user ' . $user);
    }

    /**
     * Add a provider for mount points
     *
     * @param \OCP\Files\Config\IMountProvider $provider
     */
    public function registerProvider(IMountProvider $provider) {
        $this->providers[] = $provider;
        $this->emit('\OC\Files\Config', 'registerMountProvider', [$provider]);
    }

    /**
     * Add a provider for home mount points
     *
     * @param \OCP\Files\Config\IHomeMountProvider $provider
     * @since 9.1.0
     */
    public function registerHomeProvider(IHomeMountProvider $provider) {
        $this->homeProviders[] = $provider;
        $this->emit('\OC\Files\Config', 'registerHomeMountProvider', [$provider]);
    }

    /**
     * Cache mounts for user
     *
     * @param IUser $user
     * @param IMountPoint[] $mountPoints
     */
    public function registerMounts(IUser $user, array $mountPoints) {
        $this->mountCache->registerMounts($user, $mountPoints);
    }

    /**
     * Get the mount cache which can be used to search for mounts without setting up the filesystem
     *
     * @return IUserMountCache
     */
    public function getMountCache() {
        return $this->mountCache;
    }

    /**
     * @param string $path
     * @param View $view
     * @param MountPoint[] $mountpoints
     * @return mixed
     */
    private function generateUniqueTarget($path, $view, array $mountpoints) {
        $pathinfo = \pathinfo($path);
        $ext = (isset($pathinfo['extension'])) ? '.' . $pathinfo['extension'] : '';
        $name = $pathinfo['filename'];
        $dir = $pathinfo['dirname'];

        $i = 2;
        while (\in_array($path, $mountpoints) || $view->file_exists($path)) {
            $path = Filesystem::normalizePath($dir . '/' . $name . ' ('.$i.')' . $ext);
            $i++;
        }

        return $path;
    }

    protected function getMaxMoveAttempts() {
        return \OC::$server->getConfig()
            ->getSystemValue('filesystem.max_mountpoint_move_attempts', self::DEFAULT_MOVE_ATTEMPTS_PER_MOUNTPOINT);
    }
}