// 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_FILEREADSTREAM_H_ #define RAPIDJSON_FILEREADSTREAM_H_ #include "stream.h" #include <cstdio> #ifdef __clang__ RAPIDJSON_DIAG_PUSH RAPIDJSON_DIAG_OFF(padded) RAPIDJSON_DIAG_OFF(unreachable-code) RAPIDJSON_DIAG_OFF(missing-noreturn) #endif RAPIDJSON_NAMESPACE_BEGIN //! File byte stream for input using fread(). /*! \note implements Stream concept */ class FileReadStream { public: typedef char Ch; //!< Character type (byte). //! Constructor. /*! \param fp File pointer opened for read. \param buffer user-supplied buffer. \param bufferSize size of buffer in bytes. Must >=4 bytes. */ FileReadStream(std::FILE* fp, char* buffer, size_t bufferSize) : fp_(fp), buffer_(buffer), bufferSize_(bufferSize), bufferLast_(0), current_(buffer_), readCount_(0), count_(0), eof_(false) { RAPIDJSON_ASSERT(fp_ != 0); 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: void Read() { if (current_ < bufferLast_) ++current_; else if (!eof_) { count_ += readCount_; readCount_ = std::fread(buffer_, 1, bufferSize_, fp_); bufferLast_ = buffer_ + readCount_ - 1; current_ = buffer_; if (readCount_ < bufferSize_) { buffer_[readCount_] = '\0'; ++bufferLast_; eof_ = true; } } } std::FILE* fp_; Ch *buffer_; size_t bufferSize_; Ch *bufferLast_; Ch *current_; size_t readCount_; size_t count_; //!< Number of characters read bool eof_; }; RAPIDJSON_NAMESPACE_END #ifdef __clang__ RAPIDJSON_DIAG_POP #endif #endif // RAPIDJSON_FILESTREAM_H_