mirror of https://github.com/facebook/rocksdb.git
59 lines
1.8 KiB
C++
59 lines
1.8 KiB
C++
// Copyright (c) 2014, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under the BSD-style license found in the
|
|
// LICENSE file in the root directory of this source tree. An additional grant
|
|
// of patent rights can be found in the PATENTS file in the same directory.
|
|
|
|
#pragma once
|
|
#include <string>
|
|
#include "db/merge_context.h"
|
|
#include "rocksdb/env.h"
|
|
|
|
namespace rocksdb {
|
|
class MergeContext;
|
|
|
|
class GetContext {
|
|
public:
|
|
enum GetState {
|
|
kNotFound,
|
|
kFound,
|
|
kDeleted,
|
|
kCorrupt,
|
|
kMerge // saver contains the current merge result (the operands)
|
|
};
|
|
|
|
GetContext(const Comparator* ucmp, const MergeOperator* merge_operator,
|
|
Logger* logger, Statistics* statistics, GetState init_state,
|
|
const Slice& user_key, std::string* ret_value, bool* value_found,
|
|
MergeContext* merge_context, Env* env_);
|
|
|
|
void MarkKeyMayExist();
|
|
void SaveValue(const Slice& value);
|
|
bool SaveValue(const ParsedInternalKey& parsed_key, const Slice& value);
|
|
GetState State() const { return state_; }
|
|
|
|
// If a non-null string is passed, all the SaveValue calls will be
|
|
// logged into the string. The operations can then be replayed on
|
|
// another GetContext with replayGetContextLog.
|
|
void SetReplayLog(std::string* replay_log) { replay_log_ = replay_log; }
|
|
|
|
private:
|
|
const Comparator* ucmp_;
|
|
const MergeOperator* merge_operator_;
|
|
// the merge operations encountered;
|
|
Logger* logger_;
|
|
Statistics* statistics_;
|
|
|
|
GetState state_;
|
|
Slice user_key_;
|
|
std::string* value_;
|
|
bool* value_found_; // Is value set correctly? Used by KeyMayExist
|
|
MergeContext* merge_context_;
|
|
Env* env_;
|
|
std::string* replay_log_;
|
|
};
|
|
|
|
void replayGetContextLog(const Slice& replay_log, const Slice& user_key,
|
|
GetContext* get_context);
|
|
|
|
} // namespace rocksdb
|