[HttpFoundation] use atomic writes in MockFileSessionStorage

nicolas-grekas · nicolas-grekas · commit 0d7d19c256a9 · 2021-01-13T14:01:18.000+01:00
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/MockFileSessionStorage.php b/src/Symfony/Component/HttpFoundation/Session/Storage/MockFileSessionStorage.php
@@ -103,7 +103,10 @@ public function save()
 
         try {
             if ($data) {
-                file_put_contents($this->getFilePath(), serialize($data));
+                $path = $this->getFilePath();
+                $tmp = $path.bin2hex(random_bytes(6));
+                file_put_contents($tmp, serialize($data));
+                rename($tmp, $path);
             } else {
                 $this->destroy();
             }
