Add helper method in Wrapper

Signed-off-by: Carl Schwan <carl@carlschwan.eu>

1 files changed, 20 insertions, 1 deletions

diff --git a/lib/private/Files/Storage/Wrapper/Wrapper.php b/lib/private/Files/Storage/Wrapper/Wrapper.php
index ec1da92f317..ffea74dfcac 100644
--- a/lib/private/Files/Storage/Wrapper/Wrapper.php
+++ b/lib/private/Files/Storage/Wrapper/Wrapper.php
@@ -486,7 +486,7 @@ class Wrapper implements \OC\Files\Storage\Storage, ILockingStorage, IWriteStrea
 	/**
 	 * Check if the storage is an instance of $class or is a wrapper for a storage that is an instance of $class
 	 *
-	 * @param string $class
+	 * @param class-string<IStorage> $class
 	 * @return bool
 	 */
 	public function instanceOfStorage($class) {
@@ -498,6 +498,25 @@ class Wrapper implements \OC\Files\Storage\Storage, ILockingStorage, IWriteStrea
 	}
 
 	/**
+	 * @template T of IStorage
+	 * @param class-string<T> $class
+	 * @return ?T
+	 */
+	public function getInstanceOfStorage(string $class): ?IStorage {
+		$storage = $this;
+		while ($storage->instanceOfStorage(Wrapper::class)) {
+			if ($storage instanceof $class) {
+				break;
+			}
+			$storage = $storage->getWrapperStorage();
+		}
+		if (!is_a($storage, $class)) {
+			return null;
+		}
+		return $storage;
+	}
+
+	/**
 	 * Pass any methods custom to specific storage implementations to the wrapped storage
 	 *
 	 * @param string $method