1 files changed, 47 insertions, 0 deletions
diff --git a/core/fpdfapi/page/cpdf_countedobject.h b/core/fpdfapi/page/cpdf_countedobject.h
new file mode 100644
index 0000000000..97d710cf76
--- /dev/null
+++ b/core/fpdfapi/page/cpdf_countedobject.h
@@ -0,0 +1,47 @@
+// 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
+
+#ifndef CORE_FPDFAPI_PAGE_CPDF_COUNTEDOBJECT_H_
+#define CORE_FPDFAPI_PAGE_CPDF_COUNTEDOBJECT_H_
+
+#include "core/fpdfapi/page/cpdf_colorspace.h"
+#include "core/fpdfapi/page/cpdf_pattern.h"
+#include "core/fxcrt/fx_system.h"
+
+template <class T>
+class CPDF_CountedObject {
+ public:
+  explicit CPDF_CountedObject(T* ptr) : m_nCount(1), m_pObj(ptr) {}
+  void reset(T* ptr) {  // CAUTION: tosses prior ref counts.
+    m_nCount = 1;
+    m_pObj = ptr;
+  }
+  void clear() {  // Now you're all weak ptrs ...
+    // Guard against accidental re-entry.
+    T* pObj = m_pObj;
+    m_pObj = nullptr;
+    delete pObj;
+  }
+  T* get() const { return m_pObj; }
+  T* AddRef() {
+    ASSERT(m_pObj);
+    ++m_nCount;
+    return m_pObj;
+  }
+  void RemoveRef() {
+    if (m_nCount)
+      --m_nCount;
+  }
+  size_t use_count() const { return m_nCount; }
+
+ protected:
+  size_t m_nCount;
+  T* m_pObj;
+};
+using CPDF_CountedColorSpace = CPDF_CountedObject<CPDF_ColorSpace>;
+using CPDF_CountedPattern = CPDF_CountedObject<CPDF_Pattern>;
+
+#endif  // CORE_FPDFAPI_PAGE_CPDF_COUNTEDOBJECT_H_