| // 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_ISTREAMWRAPPER_H_ |
| #define RAPIDJSON_ISTREAMWRAPPER_H_ |
| |
| #include "stream.h" |
| #include <iosfwd> |
| |
| #ifdef __clang__ |
| RAPIDJSON_DIAG_PUSH |
| RAPIDJSON_DIAG_OFF(padded) |
| #endif |
| |
| #ifdef _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; |
| BasicIStreamWrapper(StreamType& stream) : stream_(stream), count_(), peekBuffer_() {} |
| |
| Ch Peek() const { |
| typename StreamType::int_type c = stream_.peek(); |
| return RAPIDJSON_LIKELY(c != StreamType::traits_type::eof()) ? static_cast<Ch>(c) : static_cast<Ch>('\0'); |
| } |
| |
| Ch Take() { |
| typename StreamType::int_type c = stream_.get(); |
| if (RAPIDJSON_LIKELY(c != StreamType::traits_type::eof())) { |
| count_++; |
| return static_cast<Ch>(c); |
| } |
| else |
| return '\0'; |
| } |
| |
| // tellg() may return -1 when failed. So we count by ourself. |
| size_t Tell() const { return count_; } |
| |
| Ch* PutBegin() { RAPIDJSON_ASSERT(false); return 0; } |
| void Put(Ch) { RAPIDJSON_ASSERT(false); } |
| void Flush() { RAPIDJSON_ASSERT(false); } |
| size_t PutEnd(Ch*) { RAPIDJSON_ASSERT(false); return 0; } |
| |
| // For encoding detection only. |
| const Ch* Peek4() const { |
| RAPIDJSON_ASSERT(sizeof(Ch) == 1); // Only usable for byte stream. |
| int i; |
| bool hasError = false; |
| for (i = 0; i < 4; ++i) { |
| typename StreamType::int_type c = stream_.get(); |
| if (c == StreamType::traits_type::eof()) { |
| hasError = true; |
| stream_.clear(); |
| break; |
| } |
| peekBuffer_[i] = static_cast<Ch>(c); |
| } |
| for (--i; i >= 0; --i) |
| stream_.putback(peekBuffer_[i]); |
| return !hasError ? peekBuffer_ : 0; |
| } |
| |
| private: |
| BasicIStreamWrapper(const BasicIStreamWrapper&); |
| BasicIStreamWrapper& operator=(const BasicIStreamWrapper&); |
| |
| StreamType& stream_; |
| size_t count_; //!< Number of characters read. Note: |
| mutable Ch peekBuffer_[4]; |
| }; |
| |
| 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_ |