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#pragma once
#include "isa_erasure.h"
#include "reed_solomon.h"
extern "C" {
#include <contrib/libs/isa-l/include/erasure_code.h>
}
#include <util/generic/array_ref.h>
#include <array>
namespace NErasure {
template <int DataPartCount, int ParityPartCount, int WordSize, class TCodecTraits>
class TReedSolomonIsa
: public TReedSolomonBase<DataPartCount, ParityPartCount, WordSize, TCodecTraits>
{
static_assert(WordSize == 8, "ISA-l erasure codes support computations only in GF(2^8)");
public:
//! Main blob for storing data.
using TBlobType = typename TCodecTraits::TBlobType;
//! Main mutable blob for decoding data.
using TMutableBlobType = typename TCodecTraits::TMutableBlobType;
TReedSolomonIsa() {
EncodeGFTables_.resize(DataPartCount * ParityPartCount * 32, 0);
GeneratorMatrix_.resize((DataPartCount + ParityPartCount) * DataPartCount, 0);
gf_gen_rs_matrix(
GeneratorMatrix_.data(),
DataPartCount + ParityPartCount,
DataPartCount);
ec_init_tables(
DataPartCount,
ParityPartCount,
&GeneratorMatrix_.data()[DataPartCount * DataPartCount],
EncodeGFTables_.data());
}
virtual std::vector<TBlobType> Encode(const std::vector<TBlobType>& blocks) const override {
return ISAErasureEncode<DataPartCount, ParityPartCount, TCodecTraits, TBlobType, TMutableBlobType>(EncodeGFTables_, blocks);
}
virtual std::vector<TBlobType> Decode(
const std::vector<TBlobType>& blocks,
const TPartIndexList& erasedIndices) const override
{
if (erasedIndices.empty()) {
return std::vector<TBlobType>();
}
return ISAErasureDecode<DataPartCount, ParityPartCount, TCodecTraits, TBlobType, TMutableBlobType>(
blocks,
erasedIndices,
TConstArrayRef<TPartIndexList>(),
GeneratorMatrix_);
}
virtual ~TReedSolomonIsa() = default;
private:
std::vector<unsigned char> GeneratorMatrix_;
std::vector<unsigned char> EncodeGFTables_;
};
} // namespace NErasure
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