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stringbuffer.h
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14 
15 #ifndef RAPIDJSON_STRINGBUFFER_H_
16 #define RAPIDJSON_STRINGBUFFER_H_
17 
18 #include "rapidjson.h"
19 
20 #if RAPIDJSON_HAS_CXX11_RVALUE_REFS
21 #include <utility> // std::move
22 #endif
23 
24 #include "internal/stack.h"
25 
26 RAPIDJSON_NAMESPACE_BEGIN
27 
28 //! Represents an in-memory output stream.
29 /*!
30  \tparam Encoding Encoding of the stream.
31  \tparam Allocator type for allocating memory buffer.
32  \note implements Stream concept
33 */
34 template <typename Encoding, typename Allocator = CrtAllocator>
36 public:
37  typedef typename Encoding::Ch Ch;
38 
39  GenericStringBuffer(Allocator* allocator = 0, size_t capacity = kDefaultCapacity) : stack_(allocator, capacity) {}
40 
41 #if RAPIDJSON_HAS_CXX11_RVALUE_REFS
42  GenericStringBuffer(GenericStringBuffer&& rhs) : stack_(std::move(rhs.stack_)) {}
43  GenericStringBuffer& operator=(GenericStringBuffer&& rhs) {
44  if (&rhs != this)
45  stack_ = std::move(rhs.stack_);
46  return *this;
47  }
48 #endif
49 
50  void Put(Ch c) { *stack_.template Push<Ch>() = c; }
51  void Flush() {}
52 
53  void Clear() { stack_.Clear(); }
54  void ShrinkToFit() {
55  // Push and pop a null terminator. This is safe.
56  *stack_.template Push<Ch>() = '\0';
57  stack_.ShrinkToFit();
58  stack_.template Pop<Ch>(1);
59  }
60  Ch* Push(size_t count) { return stack_.template Push<Ch>(count); }
61  void Pop(size_t count) { stack_.template Pop<Ch>(count); }
62 
63  const Ch* GetString() const {
64  // Push and pop a null terminator. This is safe.
65  *stack_.template Push<Ch>() = '\0';
66  stack_.template Pop<Ch>(1);
67 
68  return stack_.template Bottom<Ch>();
69  }
70 
71  size_t GetSize() const { return stack_.GetSize(); }
72 
73  static const size_t kDefaultCapacity = 256;
74  mutable internal::Stack<Allocator> stack_;
75 
76 private:
77  // Prohibit copy constructor & assignment operator.
79  GenericStringBuffer& operator=(const GenericStringBuffer&);
80 };
81 
82 //! String buffer with UTF8 encoding
84 
85 //! Implement specialized version of PutN() with memset() for better performance.
86 template<>
87 inline void PutN(GenericStringBuffer<UTF8<> >& stream, char c, size_t n) {
88  std::memset(stream.stack_.Push<char>(n), c, n * sizeof(c));
89 }
90 
91 RAPIDJSON_NAMESPACE_END
92 
93 #endif // RAPIDJSON_STRINGBUFFER_H_
Represents an in-memory output stream.
Definition: stringbuffer.h:35
common definitions and configuration
UTF-8 encoding.
Definition: encodings.h:96
Concept for allocating, resizing and freeing memory block.
void PutN(Stream &stream, Ch c, size_t n)
Put N copies of a character to a stream.
Definition: rapidjson.h:559