comparison vendor/symfony/debug/ErrorHandler.php @ 13:5fb285c0d0e3

Update Drupal core to 8.4.7 via Composer. Security update; I *think* we've
been lucky to get away with this so far, as we don't support self-registration
which seems to be used by the so-called "drupalgeddon 2" attack that 8.4.5
was vulnerable to.

             $handler = $prev[0];
             $replace = false;
         }
         if (!$replace && $prev) {
             restore_error_handler();
-        }
-        if (is_array($prev = set_exception_handler(array($handler, 'handleException'))) && $prev[0] === $handler) {
+            $handlerIsRegistered = is_array($prev) && $handler === $prev[0];
+        } else {
+            $handlerIsRegistered = true;
+        }
+        if (is_array($prev = set_exception_handler(array($handler, 'handleException'))) && $prev[0] instanceof self) {
             restore_exception_handler();
+            if (!$handlerIsRegistered) {
+                $handler = $prev[0];
+            } elseif ($handler !== $prev[0] && $replace) {
+                set_exception_handler(array($handler, 'handleException'));
+                $p = $prev[0]->setExceptionHandler(null);
+                $handler->setExceptionHandler($p);
+                $prev[0]->setExceptionHandler($p);
+            }
         } else {
             $handler->setExceptionHandler($prev);
         }
 
         $handler->throwAt(E_ALL & $handler->thrownErrors, true);

                     $exception = $e;
                     break;
                 }
             }
         }
+        $exceptionHandler = $this->exceptionHandler;
+        $this->exceptionHandler = null;
         try {
-            if (null !== $this->exceptionHandler) {
-                return \call_user_func($this->exceptionHandler, $exception);
+            if (null !== $exceptionHandler) {
+                return \call_user_func($exceptionHandler, $exception);
             }
             $handlerException = $handlerException ?: $exception;
         } catch (\Exception $handlerException) {
         } catch (\Throwable $handlerException) {
         }
-        $this->exceptionHandler = null;
         if ($exception === $handlerException) {
             self::$reservedMemory = null; // Disable the fatal error handler
             throw $exception; // Give back $exception to the native handler
         }
         $this->handleException($handlerException);