thiru-mg commented on code in PR #3457: URL: https://github.com/apache/avro/pull/3457#discussion_r2328805121
########## lang/c++/impl/ZstdCodecWrapper.cc: ########## @@ -0,0 +1,112 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 + * + * https://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. + */ + +#ifdef ZSTD_CODEC_AVAILABLE + +#include "ZstdCodecWrapper.hh" +#include "Exception.hh" + +#include <zstd.h> + +namespace avro { + +std::vector<char> ZstdCodecWrapper::compress(const std::vector<char> &uncompressed) { + if (cctx_ == nullptr) { + initCCtx(); + } + // Pre-allocate buffer for compressed data + size_t max_compressed_size = ZSTD_compressBound(uncompressed.size()); + std::vector<char> compressed(max_compressed_size); + + // Compress the data using ZSTD block API + size_t compressed_size = ZSTD_compress( + compressed.data(), max_compressed_size, + uncompressed.data(), uncompressed.size(), + ZSTD_CLEVEL_DEFAULT); + + if (ZSTD_isError(compressed_size)) { + throw Exception("ZSTD compression error: {}", ZSTD_getErrorName(compressed_size)); + } + compressed.resize(compressed_size); + return compressed; +} + +std::string ZstdCodecWrapper::decompress(const std::vector<char> &compressed) { + if (dctx_ == nullptr) { + initDCtx(); + } + std::string uncompressed; + // Get the decompressed size + size_t decompressed_size = ZSTD_getFrameContentSize( + reinterpret_cast<const char *>(compressed.data()), compressed.size()); + if (decompressed_size == ZSTD_CONTENTSIZE_ERROR) { + throw Exception("ZSTD: Not a valid compressed frame"); + } else if (decompressed_size == ZSTD_CONTENTSIZE_UNKNOWN) { + // Stream decompress the data + ZSTD_inBuffer in{compressed.data(), compressed.size(), 0}; + std::vector<char> tmp(ZSTD_DStreamOutSize()); + ZSTD_outBuffer out{tmp.data(), tmp.size(), 0}; + size_t ret; + do { + out.pos = 0; + ret = ZSTD_decompressStream(dctx_, &out, &in); + if (ZSTD_isError(ret)) { + throw Exception("ZSTD decompression error: {}", ZSTD_getErrorName(ret)); + } + uncompressed.append(tmp.data(), out.pos); + } while (ret != 0); + } else { + // Batch decompress the data + uncompressed.resize(decompressed_size); + size_t result = ZSTD_decompress( + uncompressed.data(), decompressed_size, + reinterpret_cast<const char *>(compressed.data()), compressed.size()); + + if (ZSTD_isError(result)) { + throw Exception("ZSTD decompression error: {}", ZSTD_getErrorName(result)); + } + if (result != decompressed_size) { + throw Exception("ZSTD: Decompressed size mismatch: expected {}, got {}", + decompressed_size, result); + } + } + return uncompressed; +} + +void ZstdCodecWrapper::initCCtx() { Review Comment: This is not idiomatic C++. Initialization should happen in the constructor. This protects from being accidentally called more than once. There is nothing shared between the wrapper used for compression and the one for decompression. It will be far cleaner if we have two different wrappers - one for compression and the other for decompression. Then we don't have to worry about `cctx_`/`dctx_` being `null`. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@avro.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
