1 files changed, 42 insertions, 0 deletions
diff --git a/chromium/base/json/json_common.h b/chromium/base/json/json_common.h
new file mode 100644
index 00000000000..c0fd3eab82b
--- /dev/null
+++ b/chromium/base/json/json_common.h
@@ -0,0 +1,42 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_JSON_JSON_COMMON_H_
+#define BASE_JSON_JSON_COMMON_H_
+
+#include <stddef.h>
+
+#include "base/logging.h"
+#include "base/macros.h"
+
+namespace base {
+namespace internal {
+
+// Chosen to support 99.9% of documents found in the wild late 2016.
+// http://crbug.com/673263
+const size_t kAbsoluteMaxDepth = 200;
+
+// Simple class that checks for maximum recursion/stack overflow.
+class StackMarker {
+ public:
+  StackMarker(size_t max_depth, size_t* depth)
+      : max_depth_(max_depth), depth_(depth) {
+    ++(*depth_);
+    DCHECK_LE(*depth_, max_depth_);
+  }
+  ~StackMarker() { --(*depth_); }
+
+  bool IsTooDeep() const { return *depth_ >= max_depth_; }
+
+ private:
+  const size_t max_depth_;
+  size_t* const depth_;
+
+  DISALLOW_COPY_AND_ASSIGN(StackMarker);
+};
+
+}  // namespace internal
+}  // namespace base
+
+#endif  // BASE_JSON_JSON_COMMON_H_