129 lines
4.0 KiB
C++
129 lines
4.0 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.
|
|
//
|
|
// 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_ISTREAMWRAPPER_H_
|
|
#define RAPIDJSON_ISTREAMWRAPPER_H_
|
|
|
|
#include "stream.h"
|
|
#include <iosfwd>
|
|
#include <ios>
|
|
|
|
#ifdef __clang__
|
|
RAPIDJSON_DIAG_PUSH
|
|
RAPIDJSON_DIAG_OFF(padded)
|
|
#elif defined(_MSC_VER)
|
|
RAPIDJSON_DIAG_PUSH
|
|
RAPIDJSON_DIAG_OFF(4351) // new behavior: elements of array 'array' will be default initialized
|
|
#endif
|
|
|
|
RAPIDJSON_NAMESPACE_BEGIN
|
|
|
|
//! Wrapper of \c std::basic_istream into RapidJSON's Stream concept.
|
|
/*!
|
|
The classes can be wrapped including but not limited to:
|
|
|
|
- \c std::istringstream
|
|
- \c std::stringstream
|
|
- \c std::wistringstream
|
|
- \c std::wstringstream
|
|
- \c std::ifstream
|
|
- \c std::fstream
|
|
- \c std::wifstream
|
|
- \c std::wfstream
|
|
|
|
\tparam StreamType Class derived from \c std::basic_istream.
|
|
*/
|
|
|
|
template <typename StreamType>
|
|
class BasicIStreamWrapper {
|
|
public:
|
|
typedef typename StreamType::char_type Ch;
|
|
|
|
//! Constructor.
|
|
/*!
|
|
\param stream stream opened for read.
|
|
*/
|
|
BasicIStreamWrapper(StreamType &stream) : stream_(stream), buffer_(peekBuffer_), bufferSize_(4), bufferLast_(0), current_(buffer_), readCount_(0), count_(0), eof_(false) {
|
|
Read();
|
|
}
|
|
|
|
//! Constructor.
|
|
/*!
|
|
\param stream stream opened for read.
|
|
\param buffer user-supplied buffer.
|
|
\param bufferSize size of buffer in bytes. Must >=4 bytes.
|
|
*/
|
|
BasicIStreamWrapper(StreamType &stream, char* buffer, size_t bufferSize) : stream_(stream), buffer_(buffer), bufferSize_(bufferSize), bufferLast_(0), current_(buffer_), readCount_(0), count_(0), eof_(false) {
|
|
RAPIDJSON_ASSERT(bufferSize >= 4);
|
|
Read();
|
|
}
|
|
|
|
Ch Peek() const { return *current_; }
|
|
Ch Take() { Ch c = *current_; Read(); return c; }
|
|
size_t Tell() const { return count_ + static_cast<size_t>(current_ - buffer_); }
|
|
|
|
// Not implemented
|
|
void Put(Ch) { RAPIDJSON_ASSERT(false); }
|
|
void Flush() { RAPIDJSON_ASSERT(false); }
|
|
Ch* PutBegin() { RAPIDJSON_ASSERT(false); return 0; }
|
|
size_t PutEnd(Ch*) { RAPIDJSON_ASSERT(false); return 0; }
|
|
|
|
// For encoding detection only.
|
|
const Ch* Peek4() const {
|
|
return (current_ + 4 - !eof_ <= bufferLast_) ? current_ : 0;
|
|
}
|
|
|
|
private:
|
|
BasicIStreamWrapper();
|
|
BasicIStreamWrapper(const BasicIStreamWrapper&);
|
|
BasicIStreamWrapper& operator=(const BasicIStreamWrapper&);
|
|
|
|
void Read() {
|
|
if (current_ < bufferLast_)
|
|
++current_;
|
|
else if (!eof_) {
|
|
count_ += readCount_;
|
|
readCount_ = bufferSize_;
|
|
bufferLast_ = buffer_ + readCount_ - 1;
|
|
current_ = buffer_;
|
|
|
|
if (!stream_.read(buffer_, static_cast<std::streamsize>(bufferSize_))) {
|
|
readCount_ = static_cast<size_t>(stream_.gcount());
|
|
*(bufferLast_ = buffer_ + readCount_) = '\0';
|
|
eof_ = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
StreamType &stream_;
|
|
Ch peekBuffer_[4], *buffer_;
|
|
size_t bufferSize_;
|
|
Ch *bufferLast_;
|
|
Ch *current_;
|
|
size_t readCount_;
|
|
size_t count_; //!< Number of characters read
|
|
bool eof_;
|
|
};
|
|
|
|
typedef BasicIStreamWrapper<std::istream> IStreamWrapper;
|
|
typedef BasicIStreamWrapper<std::wistream> WIStreamWrapper;
|
|
|
|
#if defined(__clang__) || defined(_MSC_VER)
|
|
RAPIDJSON_DIAG_POP
|
|
#endif
|
|
|
|
RAPIDJSON_NAMESPACE_END
|
|
|
|
#endif // RAPIDJSON_ISTREAMWRAPPER_H_
|