]>
Commit | Line | Data |
---|---|---|
31f18b77 FG |
1 | // Tencent is pleased to support the open source community by making RapidJSON available. |
2 | // | |
3 | // Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip. All rights reserved. | |
4 | // | |
5 | // Licensed under the MIT License (the "License"); you may not use this file except | |
6 | // in compliance with the License. You may obtain a copy of the License at | |
7 | // | |
8 | // http://opensource.org/licenses/MIT | |
9 | // | |
10 | // Unless required by applicable law or agreed to in writing, software distributed | |
11 | // under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR | |
12 | // CONDITIONS OF ANY KIND, either express or implied. See the License for the | |
13 | // specific language governing permissions and limitations under the License. | |
14 | ||
15 | #ifndef RAPIDJSON_MEMORYBUFFER_H_ | |
16 | #define RAPIDJSON_MEMORYBUFFER_H_ | |
17 | ||
18 | #include "stream.h" | |
19 | #include "internal/stack.h" | |
20 | ||
21 | RAPIDJSON_NAMESPACE_BEGIN | |
22 | ||
23 | //! Represents an in-memory output byte stream. | |
24 | /*! | |
25 | This class is mainly for being wrapped by EncodedOutputStream or AutoUTFOutputStream. | |
26 | ||
27 | It is similar to FileWriteBuffer but the destination is an in-memory buffer instead of a file. | |
28 | ||
29 | Differences between MemoryBuffer and StringBuffer: | |
30 | 1. StringBuffer has Encoding but MemoryBuffer is only a byte buffer. | |
31 | 2. StringBuffer::GetString() returns a null-terminated string. MemoryBuffer::GetBuffer() returns a buffer without terminator. | |
32 | ||
33 | \tparam Allocator type for allocating memory buffer. | |
34 | \note implements Stream concept | |
35 | */ | |
36 | template <typename Allocator = CrtAllocator> | |
37 | struct GenericMemoryBuffer { | |
38 | typedef char Ch; // byte | |
39 | ||
40 | GenericMemoryBuffer(Allocator* allocator = 0, size_t capacity = kDefaultCapacity) : stack_(allocator, capacity) {} | |
41 | ||
42 | void Put(Ch c) { *stack_.template Push<Ch>() = c; } | |
43 | void Flush() {} | |
44 | ||
45 | void Clear() { stack_.Clear(); } | |
46 | void ShrinkToFit() { stack_.ShrinkToFit(); } | |
47 | Ch* Push(size_t count) { return stack_.template Push<Ch>(count); } | |
48 | void Pop(size_t count) { stack_.template Pop<Ch>(count); } | |
49 | ||
50 | const Ch* GetBuffer() const { | |
51 | return stack_.template Bottom<Ch>(); | |
52 | } | |
53 | ||
54 | size_t GetSize() const { return stack_.GetSize(); } | |
55 | ||
56 | static const size_t kDefaultCapacity = 256; | |
57 | mutable internal::Stack<Allocator> stack_; | |
58 | }; | |
59 | ||
60 | typedef GenericMemoryBuffer<> MemoryBuffer; | |
61 | ||
62 | //! Implement specialized version of PutN() with memset() for better performance. | |
63 | template<> | |
64 | inline void PutN(MemoryBuffer& memoryBuffer, char c, size_t n) { | |
65 | std::memset(memoryBuffer.stack_.Push<char>(n), c, n * sizeof(c)); | |
66 | } | |
67 | ||
68 | RAPIDJSON_NAMESPACE_END | |
69 | ||
70 | #endif // RAPIDJSON_MEMORYBUFFER_H_ |