NCBI C++ ToolKit
memorybuffer.h
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14 
15 #ifndef RAPIDJSON_MEMORYBUFFER_H_
16 #define RAPIDJSON_MEMORYBUFFER_H_
17 
18 #include "stream.h"
19 #include "internal/stack.h"
20 
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>
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;
58 };
59 
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 
69 
70 #endif // RAPIDJSON_MEMORYBUFFER_H_
Concept for allocating, resizing and freeing memory block.
A type-unsafe stack for storing different types of data.
Definition: stack.h:36
#define RAPIDJSON_NAMESPACE_BEGIN
provide custom rapidjson namespace (opening expression)
Definition: rapidjson.h:116
#define RAPIDJSON_NAMESPACE_END
provide custom rapidjson namespace (closing expression)
Definition: rapidjson.h:119
yy_size_t n
void PutN(MemoryBuffer &memoryBuffer, char c, size_t n)
Implement specialized version of PutN() with memset() for better performance.
Definition: memorybuffer.h:64
GenericMemoryBuffer< CrtAllocator > MemoryBuffer
Definition: fwd.h:74
Represents an in-memory output byte stream.
Definition: memorybuffer.h:37
const Ch * GetBuffer() const
Definition: memorybuffer.h:50
GenericMemoryBuffer(Allocator *allocator=0, size_t capacity=kDefaultCapacity)
Definition: memorybuffer.h:40
internal::Stack< Allocator > stack_
Definition: memorybuffer.h:57
Modified on Sun Apr 14 05:26:14 2024 by modify_doxy.py rev. 669887