From b18dd6ebb0b1b16aaa4004397be44c82df3aa8d0 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Fri, 28 Jun 2019 16:56:16 -0700
Subject: [PATCH] lockmanager: make NullLockManager do reference counting for
 consistency

Change-Id: I9ebdad0544ffcf87e671f4aca81a91e377c2c7ed
---
 includes/libs/lockmanager/NullLockManager.php | 27 +++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/includes/libs/lockmanager/NullLockManager.php b/includes/libs/lockmanager/NullLockManager.php
index b83462c798..339a7ee43a 100644
--- a/includes/libs/lockmanager/NullLockManager.php
+++ b/includes/libs/lockmanager/NullLockManager.php
@@ -22,15 +22,38 @@
  */
 
 /**
- * Simple version of LockManager that does nothing
+ * Simple version of LockManager that only does lock reference counting
  * @since 1.19
  */
 class NullLockManager extends LockManager {
 	protected function doLock( array $paths, $type ) {
+		foreach ( $paths as $path ) {
+			if ( isset( $this->locksHeld[$path][$type] ) ) {
+				++$this->locksHeld[$path][$type];
+			} else {
+				$this->locksHeld[$path][$type] = 1;
+			}
+		}
+
 		return StatusValue::newGood();
 	}
 
 	protected function doUnlock( array $paths, $type ) {
-		return StatusValue::newGood();
+		$status = StatusValue::newGood();
+
+		foreach ( $paths as $path ) {
+			if ( isset( $this->locksHeld[$path][$type] ) ) {
+				if ( --$this->locksHeld[$path][$type] <= 0 ) {
+					unset( $this->locksHeld[$path][$type] );
+					if ( !$this->locksHeld[$path] ) {
+						unset( $this->locksHeld[$path] ); // clean up
+					}
+				}
+			} else {
+				$status->warning( 'lockmanager-notlocked', $path );
+			}
+		}
+
+		return $status;
 	}
 }
-- 
2.20.1