Make wide strings use StringData template

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.
@@ skipping 464 matching lines @@
   return rhs != lhs;
 }
 #define FX_WSTRC(wstr) CFX_WideStringC(wstr, FX_ArraySize(wstr) - 1)
 
 // A mutable string with shared buffers using copy-on-write semantics that
 // avoids the cost of std::string's iterator stability guarantees.
 class CFX_WideString {
  public:
   typedef FX_WCHAR value_type;
 
-  CFX_WideString() : m_pData(nullptr) {}
-
-  // Copy constructor.
-  CFX_WideString(const CFX_WideString& str);
-
-  // Move constructor.
-  CFX_WideString(CFX_WideString&& other) {
-    m_pData = other.m_pData;
-    other.m_pData = nullptr;
-  }
+  CFX_WideString() {}
+  CFX_WideString(const CFX_WideString& other) : m_pData(other.m_pData) {}
+  CFX_WideString(CFX_WideString&& other) { m_pData.Swap(other.m_pData); }
 
   CFX_WideString(const FX_WCHAR* ptr)
       : CFX_WideString(ptr, ptr ? FXSYS_wcslen(ptr) : 0) {}
 
   CFX_WideString(const FX_WCHAR* ptr, FX_STRSIZE len);
   CFX_WideString(FX_WCHAR ch);
 
   CFX_WideString(const CFX_WideStringC& str);
   CFX_WideString(const CFX_WideStringC& str1, const CFX_WideStringC& str2);
 
@@ skipping 15 matching lines @@
   // Implicit conversion to C-style wide string -- deprecated.
   // Note: |this| must outlive the use of the result.
   operator const FX_WCHAR*() const { return m_pData ? m_pData->m_String : L""; }
 
   // Explicit conversion to CFX_WideStringC.
   // Note: |this| must outlive the use of the result.
   CFX_WideStringC AsWideStringC() const {
     return CFX_WideStringC(c_str(), GetLength());
   }
 
-  void Empty();
+  // Deprecated -- use clear().
+  void Empty() { m_pData.Reset(); }
+  void clear() { m_pData.Reset(); }
+
+  FX_STRSIZE GetLength() const { return m_pData ? m_pData->m_nDataLength : 0; }
   bool IsEmpty() const { return !GetLength(); }
-  FX_STRSIZE GetLength() const { return m_pData ? m_pData->m_nDataLength : 0; }
 
   const CFX_WideString& operator=(const FX_WCHAR* str);
   const CFX_WideString& operator=(const CFX_WideString& stringSrc);
   const CFX_WideString& operator=(const CFX_WideStringC& stringSrc);
 
   const CFX_WideString& operator+=(const FX_WCHAR* str);
   const CFX_WideString& operator+=(FX_WCHAR ch);
   const CFX_WideString& operator+=(const CFX_WideString& str);
   const CFX_WideString& operator+=(const CFX_WideStringC& str);
 
@@ skipping 37 matching lines @@
   FX_STRSIZE Delete(FX_STRSIZE index, FX_STRSIZE count = 1);
 
   void Format(const FX_WCHAR* lpszFormat, ...);
   void FormatV(const FX_WCHAR* lpszFormat, va_list argList);
 
   void MakeLower();
   void MakeUpper();
 
   void TrimRight();
   void TrimRight(FX_WCHAR chTarget);
-  void TrimRight(const FX_WCHAR* lpszTargets);
+  void TrimRight(const CFX_WideStringC& pTargets);
 
   void TrimLeft();
   void TrimLeft(FX_WCHAR chTarget);
-  void TrimLeft(const FX_WCHAR* lpszTargets);
+  void TrimLeft(const CFX_WideStringC& pTargets);
 
   void Reserve(FX_STRSIZE len);
   FX_WCHAR* GetBuffer(FX_STRSIZE len);
   void ReleaseBuffer(FX_STRSIZE len = -1);
 
   int GetInteger() const;
   FX_FLOAT GetFloat() const;
 
-  FX_STRSIZE Find(const FX_WCHAR* lpszSub, FX_STRSIZE start = 0) const;
+  FX_STRSIZE Find(const CFX_WideStringC& pSub, FX_STRSIZE start = 0) const;
   FX_STRSIZE Find(FX_WCHAR ch, FX_STRSIZE start = 0) const;
-  FX_STRSIZE Replace(const FX_WCHAR* lpszOld, const FX_WCHAR* lpszNew);
+  FX_STRSIZE Replace(const CFX_WideStringC& pOld, const CFX_WideStringC& pNew);
   FX_STRSIZE Remove(FX_WCHAR ch);
 
   CFX_ByteString UTF8Encode() const;
   CFX_ByteString UTF16LE_Encode() const;
 
  protected:
-  class StringData {
-   public:
-    static StringData* Create(int nLen);
-    void Retain() { ++m_nRefs; }
-    void Release() {
-      if (--m_nRefs <= 0)
-        FX_Free(this);
-    }
+  using StringData = CFX_StringDataTemplate<FX_WCHAR>;
 
-    intptr_t m_nRefs;  // Would prefer ssize_t, but no windows support.
-    FX_STRSIZE m_nDataLength;
-    FX_STRSIZE m_nAllocLength;
-    FX_WCHAR m_String[1];
-
-   private:
-    StringData(FX_STRSIZE dataLen, FX_STRSIZE allocLen)
-        : m_nRefs(1), m_nDataLength(dataLen), m_nAllocLength(allocLen) {
-      FXSYS_assert(dataLen >= 0);
-      FXSYS_assert(allocLen >= 0);
-      FXSYS_assert(dataLen <= allocLen);
-      m_String[dataLen] = 0;
-    }
-    ~StringData() = delete;
-  };
-
-  void CopyBeforeWrite();
+  void ReallocBeforeWrite(FX_STRSIZE nLen);
   void AllocBeforeWrite(FX_STRSIZE nLen);
-  void ConcatInPlace(FX_STRSIZE nSrcLen, const FX_WCHAR* lpszSrcData);
-  void ConcatCopy(FX_STRSIZE nSrc1Len,
-                  const FX_WCHAR* lpszSrc1Data,
-                  FX_STRSIZE nSrc2Len,
-                  const FX_WCHAR* lpszSrc2Data);
-  void AssignCopy(FX_STRSIZE nSrcLen, const FX_WCHAR* lpszSrcData);
   void AllocCopy(CFX_WideString& dest,
                  FX_STRSIZE nCopyLen,
                  FX_STRSIZE nCopyIndex) const;
+  void AssignCopy(const FX_WCHAR* pSrcData, FX_STRSIZE nSrcLen);
+  void Concat(const FX_WCHAR* lpszSrcData, FX_STRSIZE nSrcLen);
 
-  StringData* m_pData;
+  CFX_RetainPtr<StringData> m_pData;
   friend class fxcrt_WideStringConcatInPlace_Test;
 };
 
 inline CFX_WideStringC& CFX_WideStringC::operator=(const CFX_WideString& src) {
   m_Ptr = src.c_str();
   m_Length = src.GetLength();
   return *this;
 }
 
 inline CFX_WideString operator+(const CFX_WideStringC& str1,
@@ skipping 62 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.c_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_