Packages

rocksdb

0.22.0
3.1.2 3.1.1 3.1.0 3.0.0 2.6.2 2.6.1 retired 2.6.0 retired 2.5.0 2.4.1 2.4.0 2.3.0 2.2.0 2.1.0 2.0.0 1.9.0 1.8.0 1.7.0 1.6.0 1.5.1 1.5.0 1.4.0 1.3.2 1.3.1 1.3.0 1.2.0 1.1.1 1.1.0 1.0.0 0.26.2 0.26.1 0.26.0 0.25.0 0.24.0 0.23.3 0.23.2 0.23.1 0.23.0 0.22.0 0.21.0 0.20.1 0.20.0 0.19.0 0.18.0 0.17.0 0.16.0 0.15.0 0.14.0 0.13.1 0.13.0 0.12.0 0.11.0 0.10.0 0.9.1 0.9.0 0.8.2 0.8.1 0.8.0 0.7.1 0.7.0 0.6.4 0.6.3 0.6.2 0.6.1 0.6.0

RocksDB for Erlang

HexDocs

Current section

Files

Jump to
Readme
64 Versions
0 Dependencies
Dependants
Files
Activity
rocksdb c_src counter_merge_operator.cc
Raw

c_src/counter_merge_operator.cc 

// Copyright (c) 2018 Benoit Chesneau

//

// This file is provided to you under the Apache License,

// Version 2.0 (the "License"); you may not use this file

// except in compliance with the License.  You may obtain

// a copy of the License at

//

//   http://www.apache.org/licenses/LICENSE-2.0

//

// Unless required by applicable law or agreed to in writing,

// software distributed under the License is distributed on an

// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

// KIND, either express or implied.  See the License for the

// specific language governing permissions and limitations

// under the License.



#include <sstream> 

#include <iostream>

#include <memory>

#include <list>

#include <algorithm>

#include <assert.h>



#include "rocksdb/slice.h"

#include "rocksdb/merge_operator.h"



#include "erl_nif.h"

#include "util.h"

#include "counter_merge_operator.h"



namespace erocksdb {



    CounterMergeOperator::CounterMergeOperator() {};



    bool CounterMergeOperator::Merge(

            const rocksdb::Slice& key,

            const rocksdb::Slice* existing_value,

            const rocksdb::Slice& value,

            std::string* new_value,

            rocksdb::Logger* logger) const {



        int counter = 0;

        if (existing_value) {

            counter = parse_int(existing_value->data());

        }

        int oper = parse_int(value.data());

        auto new_counter = counter + oper;

        *new_value = ToString<int>(new_counter);

        return true;

    }



    const char* CounterMergeOperator::Name() const  {

        return "CounterMergeOperator";

    }



    std::shared_ptr<CounterMergeOperator> CreateCounterMergeOperator() {

        return std::make_shared<CounterMergeOperator>();

    }

}