Make StringData a templated class.

core/fxcrt/include/fx_string.h

 // Copyright 2014 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_FXCRT_INCLUDE_FX_STRING_H_
 #define CORE_FXCRT_INCLUDE_FX_STRING_H_
 
 #include <stdint.h>  // For intptr_t.
 #include <algorithm>
 
+#include "core/fxcrt/cfx_string_data_template.h"
 #include "core/fxcrt/include/cfx_retain_ptr.h"
 #include "core/fxcrt/include/fx_memory.h"
 #include "core/fxcrt/include/fx_system.h"
 
 class CFX_BinaryBuf;
 class CFX_ByteString;
 class CFX_WideString;
 
 // An immutable string with caller-provided storage which must outlive the
 // string itself.
@@ skipping 252 matching lines @@
   uint32_t GetID(FX_STRSIZE start_pos = 0) const;
 
 #define FXFORMAT_SIGNED 1
 #define FXFORMAT_HEX 2
 #define FXFORMAT_CAPITAL 4
 
   static CFX_ByteString FormatInteger(int i, uint32_t flags = 0);
   static CFX_ByteString FormatFloat(FX_FLOAT f, int precision = 0);
 
  protected:
-  class StringData {
-   public:
-    static StringData* Create(FX_STRSIZE nLen);
-    static StringData* Create(const StringData& other);
-    static StringData* Create(const FX_CHAR* pStr, FX_STRSIZE nLen);
-
-    void Retain() { ++m_nRefs; }
-    void Release() {
-      if (--m_nRefs <= 0)
-        FX_Free(this);
-    }
-
-    bool CanOperateInPlace(FX_STRSIZE nTotalLen) const {
-      return m_nRefs <= 1 && nTotalLen <= m_nAllocLength;
-    }
-
-    void CopyContents(const StringData& other);
-    void CopyContents(const FX_CHAR* pStr, FX_STRSIZE nLen);
-    void CopyContentsAt(FX_STRSIZE offset,
-                        const FX_CHAR* pStr,
-                        FX_STRSIZE nLen);
-
-    // To ensure ref counts do not overflow, consider the worst possible case:
-    // the entire address space contains nothing but pointers to this object.
-    // Since the count increments with each new pointer, the largest value is
-    // the number of pointers that can fit into the address space. The size of
-    // the address space itself is a good upper bound on it.
-    intptr_t m_nRefs;  // Would prefer ssize_t, but no windows support.
-
-    // |FX_STRSIZE| is currently typedef'd as |int|.
-    // TODO(palmer): It should be a |size_t|, or at least unsigned.
-    // These lengths do not include the terminating NUL, but the underlying
-    // buffer is sized to be capable of holding it.
-    FX_STRSIZE m_nDataLength;
-    FX_STRSIZE m_nAllocLength;
-
-    // Not really 1, variable size.
-    FX_CHAR m_String[1];
-
-   private:
-    StringData(FX_STRSIZE dataLen, FX_STRSIZE allocLen);
-    ~StringData() = delete;
-  };
+  using StringData = CFX_StringDataTemplate<FX_CHAR>;
 
   void ReallocBeforeWrite(FX_STRSIZE nNewLen);
   void AllocBeforeWrite(FX_STRSIZE nNewLen);
   void AllocCopy(CFX_ByteString& dest,
                  FX_STRSIZE nCopyLen,
                  FX_STRSIZE nCopyIndex) const;
   void AssignCopy(const FX_CHAR* pSrcData, FX_STRSIZE nSrcLen);
   void Concat(const FX_CHAR* lpszSrcData, FX_STRSIZE nSrcLen);
 
   CFX_RetainPtr<StringData> m_pData;
@@ skipping 425 matching lines @@
 }
 
 FX_FLOAT FX_atof(const CFX_ByteStringC& str);
 inline FX_FLOAT FX_atof(const CFX_WideStringC& wsStr) {
   return FX_atof(FX_UTF8Encode(wsStr.raw_str(), wsStr.GetLength()).c_str());
 }
 void FX_atonum(const CFX_ByteStringC& str, FX_BOOL& bInteger, void* pData);
 FX_STRSIZE FX_ftoa(FX_FLOAT f, FX_CHAR* buf);
 
 #endif  // CORE_FXCRT_INCLUDE_FX_STRING_H_