From 8ce2b9763c880084fd9d38fae6033e487fde58d9 Mon Sep 17 00:00:00 2001 From: Harsh Sharma Date: Thu, 19 Dec 2019 11:53:10 -0600 Subject: Initial commit --- include/rapidjson/filereadstream.h | 99 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 include/rapidjson/filereadstream.h (limited to 'include/rapidjson/filereadstream.h') diff --git a/include/rapidjson/filereadstream.h b/include/rapidjson/filereadstream.h new file mode 100644 index 0000000..6b34370 --- /dev/null +++ b/include/rapidjson/filereadstream.h @@ -0,0 +1,99 @@ +// 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_FILEREADSTREAM_H_ +#define RAPIDJSON_FILEREADSTREAM_H_ + +#include "stream.h" +#include + +#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(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_ -- cgit v1.2.3