monero/external/rapidjson/stringbuffer.h

118 lines
3.7 KiB
C++

// 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_STRINGBUFFER_H_
#define RAPIDJSON_STRINGBUFFER_H_
#include "stream.h"
#include "internal/stack.h"
#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
#include <utility> // std::move
#endif
#include "internal/stack.h"
#if defined(__clang__)
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(c++98-compat)
#endif
RAPIDJSON_NAMESPACE_BEGIN
//! Represents an in-memory output stream.
/*!
\tparam Encoding Encoding of the stream.
\tparam Allocator type for allocating memory buffer.
\note implements Stream concept
*/
template <typename Encoding, typename Allocator = CrtAllocator>
class GenericStringBuffer {
public:
typedef typename Encoding::Ch Ch;
GenericStringBuffer(Allocator* allocator = 0, size_t capacity = kDefaultCapacity) : stack_(allocator, capacity) {}
#if RAPIDJSON_HAS_CXX11_RVALUE_REFS
GenericStringBuffer(GenericStringBuffer&& rhs) : stack_(std::move(rhs.stack_)) {}
GenericStringBuffer& operator=(GenericStringBuffer&& rhs) {
if (&rhs != this)
stack_ = std::move(rhs.stack_);
return *this;
}
#endif
void Put(Ch c) { *stack_.template Push<Ch>() = c; }
void PutUnsafe(Ch c) { *stack_.template PushUnsafe<Ch>() = c; }
void Flush() {}
void Clear() { stack_.Clear(); }
void ShrinkToFit() {
// Push and pop a null terminator. This is safe.
*stack_.template Push<Ch>() = '\0';
stack_.ShrinkToFit();
stack_.template Pop<Ch>(1);
}
void Reserve(size_t count) { stack_.template Reserve<Ch>(count); }
Ch* Push(size_t count) { return stack_.template Push<Ch>(count); }
Ch* PushUnsafe(size_t count) { return stack_.template PushUnsafe<Ch>(count); }
void Pop(size_t count) { stack_.template Pop<Ch>(count); }
const Ch* GetString() const {
// Push and pop a null terminator. This is safe.
*stack_.template Push<Ch>() = '\0';
stack_.template Pop<Ch>(1);
return stack_.template Bottom<Ch>();
}
size_t GetSize() const { return stack_.GetSize(); }
static const size_t kDefaultCapacity = 256;
mutable internal::Stack<Allocator> stack_;
private:
// Prohibit copy constructor & assignment operator.
GenericStringBuffer(const GenericStringBuffer&);
GenericStringBuffer& operator=(const GenericStringBuffer&);
};
//! String buffer with UTF8 encoding
typedef GenericStringBuffer<UTF8<> > StringBuffer;
template<typename Encoding, typename Allocator>
inline void PutReserve(GenericStringBuffer<Encoding, Allocator>& stream, size_t count) {
stream.Reserve(count);
}
template<typename Encoding, typename Allocator>
inline void PutUnsafe(GenericStringBuffer<Encoding, Allocator>& stream, typename Encoding::Ch c) {
stream.PutUnsafe(c);
}
//! Implement specialized version of PutN() with memset() for better performance.
template<>
inline void PutN(GenericStringBuffer<UTF8<> >& stream, char c, size_t n) {
std::memset(stream.stack_.Push<char>(n), c, n * sizeof(c));
}
RAPIDJSON_NAMESPACE_END
#if defined(__clang__)
RAPIDJSON_DIAG_POP
#endif
#endif // RAPIDJSON_STRINGBUFFER_H_