1 files changed, 79 insertions, 0 deletions
diff --git a/lib/public/Files/DavUtil.php b/lib/public/Files/DavUtil.php
new file mode 100644
index 00000000000..6dde3179bb8
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+++ b/lib/public/Files/DavUtil.php
@@ -0,0 +1,79 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2022 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+namespace OCP\Files;
+
+use OCP\Constants;
+use OCP\Files\Mount\IMovableMount;
+
+/**
+ * This class provides different helper functions related to WebDAV protocol
+ *
+ * @since 25.0.0
+ */
+class DavUtil {
+	/**
+	 * Compute the fileId to use for dav responses
+	 *
+	 * @param int $id Id of the file returned by FileInfo::getId
+	 * @since 25.0.0
+	 */
+	public static function getDavFileId(int $id): string {
+		$instanceId = \OC_Util::getInstanceId();
+		$id = sprintf('%08d', $id);
+		return $id . $instanceId;
+	}
+
+	/**
+	 * Compute the format needed for returning permissions for dav
+	 *
+	 * @since 25.0.0
+	 */
+	public static function getDavPermissions(FileInfo $info): string {
+		$permissions = $info->getPermissions();
+		$p = '';
+		if ($info->isShared()) {
+			$p .= 'S';
+		}
+		if ($permissions & Constants::PERMISSION_SHARE) {
+			$p .= 'R';
+		}
+		if ($info->isMounted()) {
+			$p .= 'M';
+		}
+		if ($permissions & Constants::PERMISSION_READ) {
+			$p .= 'G';
+		}
+		if ($permissions & Constants::PERMISSION_DELETE) {
+			$p .= 'D';
+		}
+		if ($permissions & Constants::PERMISSION_UPDATE) {
+			$p .= 'NV'; // Renameable, Movable
+		}
+
+		// since we always add update permissions for the root of movable mounts
+		// we need to check the shared cache item directly to determine if it's writable
+		$storage = $info->getStorage();
+		if ($info->getInternalPath() === '' && $info->getMountPoint() instanceof IMovableMount) {
+			$rootEntry = $storage->getCache()->get('');
+			$isWritable = $rootEntry->getPermissions() & Constants::PERMISSION_UPDATE;
+		} else {
+			$isWritable = $permissions & Constants::PERMISSION_UPDATE;
+		}
+
+		if ($info->getType() === FileInfo::TYPE_FILE) {
+			if ($isWritable) {
+				$p .= 'W';
+			}
+		} else {
+			if ($permissions & Constants::PERMISSION_CREATE) {
+				$p .= 'CK';
+			}
+		}
+		return $p;
+	}
+}