1 files changed, 52 insertions, 0 deletions
diff --git a/core/fpdfdoc/cpdf_numbertree.cpp b/core/fpdfdoc/cpdf_numbertree.cpp
new file mode 100644
index 0000000000..9e2881f414
--- /dev/null
+++ b/core/fpdfdoc/cpdf_numbertree.cpp
@@ -0,0 +1,52 @@
+// Copyright 2016 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "core/fpdfdoc/cpdf_numbertree.h"
+
+#include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
+#include "core/fpdfapi/fpdf_parser/include/cpdf_dictionary.h"
+
+namespace {
+
+CPDF_Object* SearchNumberNode(const CPDF_Dictionary* pNode, int num) {
+  CPDF_Array* pLimits = pNode->GetArrayBy("Limits");
+  if (pLimits &&
+      (num < pLimits->GetIntegerAt(0) || num > pLimits->GetIntegerAt(1))) {
+    return nullptr;
+  }
+  CPDF_Array* pNumbers = pNode->GetArrayBy("Nums");
+  if (pNumbers) {
+    for (size_t i = 0; i < pNumbers->GetCount() / 2; i++) {
+      int index = pNumbers->GetIntegerAt(i * 2);
+      if (num == index)
+        return pNumbers->GetDirectObjectAt(i * 2 + 1);
+      if (index > num)
+        break;
+    }
+    return nullptr;
+  }
+
+  CPDF_Array* pKids = pNode->GetArrayBy("Kids");
+  if (!pKids)
+    return nullptr;
+
+  for (size_t i = 0; i < pKids->GetCount(); i++) {
+    CPDF_Dictionary* pKid = pKids->GetDictAt(i);
+    if (!pKid)
+      continue;
+
+    CPDF_Object* pFound = SearchNumberNode(pKid, num);
+    if (pFound)
+      return pFound;
+  }
+  return nullptr;
+}
+
+}  // namespace
+
+CPDF_Object* CPDF_NumberTree::LookupValue(int num) const {
+  return SearchNumberNode(m_pRoot, num);
+}