3 files changed, 44 insertions, 2 deletions
diff --git a/lib/private/session/internal.php b/lib/private/session/internal.php
index a7c9e2fdefd..42ec9606dc9 100644
--- a/lib/private/session/internal.php
+++ b/lib/private/session/internal.php
@@ -26,8 +26,7 @@ class Internal extends Memory {
 	}
 
 	public function __destruct() {
-		$_SESSION = array_merge($_SESSION, $this->data);
-		session_write_close();
+		$this->close();
 	}
 
 	/**
@@ -47,4 +46,15 @@ class Internal extends Memory {
 		@session_start();
 		$this->data = $_SESSION = array();
 	}
+
+	public function close() {
+		$_SESSION = array_merge($_SESSION, $this->data);
+		session_write_close();
+
+		parent::close();
+	}
+
+    public function reopen() {
+        throw new \Exception('The session cannot be reopened - reopen() is ony to be used in unit testing.');
+    }
 }
diff --git a/lib/private/session/memory.php b/lib/private/session/memory.php
index 1b9ac452575..1497c0f8928 100644
--- a/lib/private/session/memory.php
+++ b/lib/private/session/memory.php
@@ -28,6 +28,7 @@ class Memory extends Session {
 	 * @param integer $value
 	 */
 	public function set($key, $value) {
+		$this->validateSession();
 		$this->data[$key] = $value;
 	}
 
@@ -54,10 +55,29 @@ class Memory extends Session {
 	 * @param string $key
 	 */
 	public function remove($key) {
+		$this->validateSession();
 		unset($this->data[$key]);
 	}
 
 	public function clear() {
 		$this->data = array();
 	}
+
+	/**
+	 * Helper function for PHPUnit execution - don't use in non-test code
+	 */
+	public function reopen() {
+		$this->sessionClosed = false;
+	}
+
+	/**
+	 * In case the session has already been locked an exception will be thrown
+	 *
+	 * @throws \Exception
+	 */
+	private function validateSession() {
+		if ($this->sessionClosed) {
+			throw new \Exception('Session has been closed - no further changes to the session as allowed');
+		}
+	}
 }
diff --git a/lib/private/session/session.php b/lib/private/session/session.php
index fe160faa267..6f6c804f384 100644
--- a/lib/private/session/session.php
+++ b/lib/private/session/session.php
@@ -13,6 +13,11 @@ use OCP\ISession;
 abstract class Session implements \ArrayAccess, ISession {
 
 	/**
+	 * @var bool
+	 */
+	protected $sessionClosed = false;
+
+	/**
 	 * $name serves as a namespace for the session keys
 	 *
 	 * @param string $name
@@ -49,4 +54,11 @@ abstract class Session implements \ArrayAccess, ISession {
 	public function offsetUnset($offset) {
 		$this->remove($offset);
 	}
+
+	/**
+	 * Close the session and release the lock
+	 */
+	public function close() {
+		$this->sessionClosed = true;
+	}
 }