decompression_algorithm_lz4.h

/*
 * Copyright (c) 2019, 2025, Oracle and/or its affiliates.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2.0,
 * as published by the Free Software Foundation.
 *
 * This program is designed to work with certain software (including
 * but not limited to OpenSSL) that is licensed under separate terms,
 * as designated in a particular file or component or in included license
 * documentation. The authors of MySQL hereby grant you an additional
 * permission to link the program and your derivative works with the
 * separately licensed software that they have either included with
 * the program or referenced in the documentation.
 *
 * This program is distributed in the hope that it will be useful,
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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*/
#ifndef PLUGIN_X_PROTOCOL_STREAM_COMPRESSION_DECOMPRESSION_ALGORITHM_LZ4_H_
#definePLUGIN_X_PROTOCOL_STREAM_COMPRESSION_DECOMPRESSION_ALGORITHM_LZ4_H_

#include<lz4frame.h>

#include"my_dbug.h"

#include"plugin/x/protocol/stream/compression/decompression_algorithm_interface.h"

namespaceprotocol {

classDecompression_algorithm_lz4 : publicDecompression_algorithm_interface {
public:
Decompression_algorithm_lz4() {
LZ4F_createDecompressionContext(&m_ctxt, LZ4F_VERSION);
 }

~Decompression_algorithm_lz4() override {
LZ4F_freeDecompressionContext(m_ctxt);
 }

boolneeds_input() constoverride { return m_decoded_whole_input; }

voidset_input(uint8_t *in_ptr, constint in_size) override {
 DBUG_TRACE;
 m_input_buffer_data_size = in_size;
 m_input_buffer_ptr = in_ptr;
 m_decoded_whole_input = false;
 }

booldecompress(uint8_t *out_ptr, int64_t *out_size) override {
 DBUG_TRACE;
size_t output_buffer_size = *out_size;
size_t input_size = static_cast<size_t>(m_input_buffer_data_size);

constauto result =
LZ4F_decompress(m_ctxt, out_ptr, &output_buffer_size,
 m_input_buffer_ptr, &input_size, nullptr);

if (LZ4F_isError(result)) {
 m_valid = false;
DBUG_LOG("debug", "LZ4F error:" << LZ4F_getErrorName(result));
 *out_size = 0;
returnfalse;
 }

 *out_size = output_buffer_size;

 m_input_buffer_data_size -= input_size;
 m_input_buffer_ptr += input_size;

 m_decoded_whole_input = (result == 0 || output_buffer_size == 0) &&
0 == m_input_buffer_data_size;

DBUG_LOG("debug", "out_size:" << *out_size
 << ", need-more:" << m_decoded_whole_input);

returntrue;
 }

boolwas_error() constoverride {
 DBUG_TRACE;
return !m_valid;
 }

private:
 LZ4F_decompressionContext_t m_ctxt;
int m_input_buffer_data_size = 0;
bool m_decoded_whole_input = true;
uint8_t *m_input_buffer_ptr = nullptr;
bool m_valid = true;
};

} // namespace protocol

#endif// PLUGIN_X_PROTOCOL_STREAM_COMPRESSION_DECOMPRESSION_ALGORITHM_LZ4_H_