adding an explicit close method to class session - write operations (set and remove) being called after close() will throw an exception

lib/private/session/internal.php

@@ -27,7 +27,7 @@ class Internal extends Memory {
 
 	public function __destruct() {
 		$_SESSION = array_merge($_SESSION, $this->data);
-		session_write_close();
+		\OC::$session->close();
 	}
 
 	/**

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 +55,17 @@ class Memory extends Session {
 	 * @param string $key
 	 */
 	public function remove($key) {
+		$this->validateSession();
 		unset($this->data[$key]);
 	}
 
 	public function clear() {
 		$this->data = array();
 	}
+
+	private function validateSession() {
+		if ($this->sessionClosed) {
+			throw new \Exception('Session has been closed - no further changes to the session as allowed');
+		}
+	}
 }

lib/private/session/session.php

@@ -49,4 +49,10 @@ abstract class Session implements \ArrayAccess, ISession {
 	public function offsetUnset($offset) {
 		$this->remove($offset);
 	}
+
+	protected $sessionClosed = false;
+
+	public function close() {
+		$this->sessionClosed = true;
+	}
 }

lib/public/isession.php

@@ -75,4 +75,9 @@ interface ISession {
 	 */
 	public function clear();
 
+	/**
+	 * Close the session and release the lock
+	 */
+	public function close();
+
 }