1 files changed, 81 insertions, 0 deletions
diff --git a/apps/dav/lib/Connector/Sabre/LockPlugin.php b/apps/dav/lib/Connector/Sabre/LockPlugin.php
new file mode 100644
index 00000000000..6640771dc31
--- /dev/null
+++ b/apps/dav/lib/Connector/Sabre/LockPlugin.php
@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+namespace OCA\DAV\Connector\Sabre;
+
+use OCA\DAV\Connector\Sabre\Exception\FileLocked;
+use OCP\Lock\ILockingProvider;
+use OCP\Lock\LockedException;
+use Sabre\DAV\Exception\NotFound;
+use Sabre\DAV\ServerPlugin;
+use Sabre\HTTP\RequestInterface;
+
+class LockPlugin extends ServerPlugin {
+	/**
+	 * Reference to main server object
+	 *
+	 * @var \Sabre\DAV\Server
+	 */
+	private $server;
+
+	/**
+	 * State of the lock
+	 *
+	 * @var bool
+	 */
+	private $isLocked;
+
+	/**
+	 * {@inheritdoc}
+	 */
+	public function initialize(\Sabre\DAV\Server $server) {
+		$this->server = $server;
+		$this->server->on('beforeMethod:*', [$this, 'getLock'], 50);
+		$this->server->on('afterMethod:*', [$this, 'releaseLock'], 50);
+		$this->isLocked = false;
+	}
+
+	public function getLock(RequestInterface $request) {
+		// we can't listen on 'beforeMethod:PUT' due to order of operations with setting up the tree
+		// so instead we limit ourselves to the PUT method manually
+		if ($request->getMethod() !== 'PUT') {
+			return;
+		}
+		try {
+			$node = $this->server->tree->getNodeForPath($request->getPath());
+		} catch (NotFound $e) {
+			return;
+		}
+		if ($node instanceof Node) {
+			try {
+				$node->acquireLock(ILockingProvider::LOCK_SHARED);
+			} catch (LockedException $e) {
+				throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+			}
+			$this->isLocked = true;
+		}
+	}
+
+	public function releaseLock(RequestInterface $request) {
+		// don't try to release the lock if we never locked one
+		if ($this->isLocked === false) {
+			return;
+		}
+		if ($request->getMethod() !== 'PUT') {
+			return;
+		}
+		try {
+			$node = $this->server->tree->getNodeForPath($request->getPath());
+		} catch (NotFound $e) {
+			return;
+		}
+		if ($node instanceof Node) {
+			$node->releaseLock(ILockingProvider::LOCK_SHARED);
+			$this->isLocked = false;
+		}
+	}
+}