| // 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_FXCRT_STRING_DATA_TEMPLATE_H_ |
| #define CORE_FXCRT_STRING_DATA_TEMPLATE_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| namespace fxcrt { |
| |
| template <typename CharType> |
| class StringDataTemplate { |
| public: |
| static StringDataTemplate* Create(size_t nLen); |
| static StringDataTemplate* Create(const CharType* pStr, size_t nLen); |
| |
| void Retain() { ++m_nRefs; } |
| void Release(); |
| |
| bool CanOperateInPlace(size_t nTotalLen) const { |
| return m_nRefs <= 1 && nTotalLen <= m_nAllocLength; |
| } |
| |
| void CopyContents(const StringDataTemplate& other); |
| void CopyContents(const CharType* pStr, size_t nLen); |
| void CopyContentsAt(size_t offset, const CharType* pStr, size_t 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 = 0; |
| |
| // These lengths are in terms of number of characters, not bytes, and do not |
| // include the terminating NUL character, but the underlying buffer is sized |
| // to be capable of holding it. |
| size_t m_nDataLength; |
| const size_t m_nAllocLength; |
| |
| // Not really 1, variable size. |
| CharType m_String[1]; |
| |
| private: |
| StringDataTemplate(size_t dataLen, size_t allocLen); |
| ~StringDataTemplate() = delete; |
| }; |
| |
| } // namespace fxcrt |
| |
| using fxcrt::StringDataTemplate; |
| |
| #endif // CORE_FXCRT_STRING_DATA_TEMPLATE_H_ |