rocksdb/utilities/merge_operators/put_operator.h

57 lines
2.3 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).
//
// A merge operator that mimics Put semantics
// Since this merge-operator will not be used in production,
// it is implemented as a non-associative merge operator to illustrate the
// new interface and for testing purposes. (That is, we inherit from
// the MergeOperator class rather than the AssociativeMergeOperator
// which would be simpler in this case).
//
// From the client-perspective, semantics are the same.
#pragma once
#include "rocksdb/merge_operator.h"
namespace ROCKSDB_NAMESPACE {
class Logger;
class Slice;
class PutOperator : public MergeOperator {
public:
static const char* kClassName() { return "PutOperator"; }
static const char* kNickName() { return "put_v1"; }
const char* Name() const override { return kClassName(); }
const char* NickName() const override { return kNickName(); }
bool FullMerge(const Slice& /*key*/, const Slice* /*existing_value*/,
const std::deque<std::string>& operand_sequence,
std::string* new_value, Logger* /*logger*/) const override;
bool PartialMerge(const Slice& /*key*/, const Slice& left_operand,
const Slice& right_operand, std::string* new_value,
Logger* /*logger*/) const override;
using MergeOperator::PartialMergeMulti;
bool PartialMergeMulti(const Slice& /*key*/,
const std::deque<Slice>& operand_list,
std::string* new_value,
Logger* /*logger*/) const override;
};
class PutOperatorV2 : public PutOperator {
public:
static const char* kNickName() { return "put"; }
const char* NickName() const override { return kNickName(); }
bool FullMerge(const Slice& /*key*/, const Slice* /*existing_value*/,
const std::deque<std::string>& /*operand_sequence*/,
std::string* /*new_value*/, Logger* /*logger*/) const override;
bool FullMergeV2(const MergeOperationInput& merge_in,
MergeOperationOutput* merge_out) const override;
};
} // namespace ROCKSDB_NAMESPACE