rocksdb/utilities/merge_operators/bytesxor.h

40 lines
1.4 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include <algorithm>
#include <memory>
#include <string>
#include "rocksdb/env.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/slice.h"
#include "util/coding.h"
#include "utilities/merge_operators.h"
namespace ROCKSDB_NAMESPACE {
// A 'model' merge operator that XORs two (same sized) array of bytes.
// Implemented as an AssociativeMergeOperator for simplicity and example.
class BytesXOROperator : public AssociativeMergeOperator {
public:
// XORs the two array of bytes one byte at a time and stores the result
// in new_value. len is the number of xored bytes, and the length of new_value
bool Merge(const Slice& key, const Slice* existing_value, const Slice& value,
std::string* new_value, Logger* logger) const override;
static const char* kClassName() { return "BytesXOR"; }
static const char* kNickName() { return "bytesxor"; }
const char* NickName() const override { return kNickName(); }
const char* Name() const override { return kClassName(); }
void XOR(const Slice* existing_value, const Slice& value,
std::string* new_value) const;
};
} // namespace ROCKSDB_NAMESPACE