| // Tencent is pleased to support the open source community by making RapidJSON available. |
| // |
| // Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved. |
| // |
| // Licensed under the MIT License (the "License"); you may not use this file except |
| // in compliance with the License. You may obtain a copy of the License at |
| // |
| // http://opensource.org/licenses/MIT |
| // |
| // Unless required by applicable law or agreed to in writing, software distributed |
| // under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR |
| // CONDITIONS OF ANY KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations under the License. |
| |
| #ifndef RAPIDJSON_MEMORYBUFFER_H_ |
| #define RAPIDJSON_MEMORYBUFFER_H_ |
| |
| #include "stream.h" |
| #include "internal/stack.h" |
| |
| RAPIDJSON_NAMESPACE_BEGIN |
| |
| //! Represents an in-memory output byte stream. |
| /*! |
| This class is mainly for being wrapped by EncodedOutputStream or AutoUTFOutputStream. |
| |
| It is similar to FileWriteBuffer but the destination is an in-memory buffer instead of a file. |
| |
| Differences between MemoryBuffer and StringBuffer: |
| 1. StringBuffer has Encoding but MemoryBuffer is only a byte buffer. |
| 2. StringBuffer::GetString() returns a null-terminated string. MemoryBuffer::GetBuffer() returns a buffer without terminator. |
| |
| \tparam Allocator type for allocating memory buffer. |
| \note implements Stream concept |
| */ |
| template <typename Allocator = CrtAllocator> |
| struct GenericMemoryBuffer { |
| typedef char Ch; // byte |
| |
| GenericMemoryBuffer(Allocator* allocator = 0, size_t capacity = kDefaultCapacity) : stack_(allocator, capacity) {} |
| |
| void Put(Ch c) { *stack_.template Push<Ch>() = c; } |
| void Flush() {} |
| |
| void Clear() { stack_.Clear(); } |
| void ShrinkToFit() { stack_.ShrinkToFit(); } |
| Ch* Push(size_t count) { return stack_.template Push<Ch>(count); } |
| void Pop(size_t count) { stack_.template Pop<Ch>(count); } |
| |
| const Ch* GetBuffer() const { |
| return stack_.template Bottom<Ch>(); |
| } |
| |
| size_t GetSize() const { return stack_.GetSize(); } |
| |
| static const size_t kDefaultCapacity = 256; |
| mutable internal::Stack<Allocator> stack_; |
| }; |
| |
| typedef GenericMemoryBuffer<> MemoryBuffer; |
| |
| //! Implement specialized version of PutN() with memset() for better performance. |
| template<> |
| inline void PutN(MemoryBuffer& memoryBuffer, char c, size_t n) { |
| std::memset(memoryBuffer.stack_.Push<char>(n), c, n * sizeof(c)); |
| } |
| |
| RAPIDJSON_NAMESPACE_END |
| |
| #endif // RAPIDJSON_MEMORYBUFFER_H_ |