// Copyright (c) 2018 PaddlePaddle Authors. All Rights Reserved. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // 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. #pragma once #include namespace paddle { namespace recordio { // Default ChunkSize constexpr size_t kDefaultMaxChunkSize = 32 * 1024 * 1024; // MagicNumber for memory checking constexpr uint32_t kMagicNumber = 0x01020304; enum class Compressor { // NoCompression means writing raw chunk data into files. // With other choices, chunks are compressed before written. kNoCompress = 0, // Snappy had been the default compressing algorithm widely // used in Google. It compromises between speech and // compression ratio. kSnappy = 1, // Gzip is a well-known compression algorithm. It is // recommmended only you are looking for compression ratio. kGzip = 2, }; // Header is the metadata of Chunk class Header { public: Header(); Header(uint32_t num, uint32_t sum, Compressor ct, uint32_t cs); void Write(std::ostream& os); void Parse(std::istream& iss); uint32_t NumRecords() const { return num_records_; } uint32_t Checksum() const { return checksum_; } Compressor CompressType() const { return compressor_; } uint32_t CompressSize() const { return compress_size_; } private: uint32_t num_records_; uint32_t checksum_; Compressor compressor_; uint32_t compress_size_; }; // Allow Header Loggable std::ostream& operator<<(std::ostream& os, Header h); bool operator==(Header l, Header r); } // namespace recordio } // namespace paddle