add some recrusive detection/prevention

Signed-off-by: Robin Appelman <robin@icewind.nl>

Author: icewind1991

apps/files_sharing/lib/SharedStorage.php

@@ -41,6 +41,7 @@
 use OC\Files\Storage\FailedStorage;
 use OC\Files\Storage\Home;
 use OC\Files\Storage\Wrapper\PermissionsMask;
+use OC\Files\Storage\Wrapper\Wrapper;
 use OC\User\NoUserException;
 use OCA\Files_External\Config\ExternalMountPoint;
 use OCP\Constants;
@@ -410,11 +411,10 @@ public function getCache($path = '', $storage = null) {
 			return new FailedCache();
 		}
 
-		$this->cache = new Cache(
+		$this->cache = new \OCA\Files_Sharing\Cache(
 			$storage,
 			$sourceRoot,
-			\OC::$server->get(CacheDependencies::class),
-			$this->getShare()
+			\OC::$server->get(DisplayNameCache::class)
 		);
 		return $this->cache;
 	}

lib/private/Files/Storage/Wrapper/Wrapper.php

@@ -654,4 +654,15 @@ public function writeStream(string $path, $stream, int $size = null): int {
 	public function getDirectoryContent($directory): \Traversable {
 		return $this->getWrapperStorage()->getDirectoryContent($directory);
 	}
+
+	public function isWrapperOf(IStorage $storage) {
+		$wrapped = $this->getWrapperStorage();
+		if ($wrapped === $storage) {
+			return true;
+		}
+		if ($wrapped instanceof Wrapper) {
+			return $wrapped->isWrapperOf($storage);
+		}
+		return false;
+	}
 }