// Licensed to the Apache Software Foundation (ASF) under one

// or more contributor license agreements.  See the NOTICE file

// distributed with this work for additional information

// regarding copyright ownership.  The ASF licenses this file

// 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.

// the following code are modified from RocksDB:

// https://github.com/facebook/rocksdb/blob/master/util/crc32c.h

#pragma once

#include <stddef.h>

#include <stdint.h>

#include <vector>

#include "util/slice.h"

namespace doris {

namespace crc32c {

// Return the crc32c of concat(A, data[0,n-1]) where init_crc is the

// crc32c of some string A.  Extend() is often used to maintain the

// crc32c of a stream of data.

extern uint32_t Extend(uint32_t init_crc, const char* data, size_t n);

// Return the crc32c of data[0,n-1]

inline uint32_t Value(const char* data, size_t n) {

    return Extend(0, data, n);

}

// Return the crc32c of data content in all slices

inline uint32_t Value(const std::vector<Slice>& slices) {

    uint32_t crc = 0;

    for (auto& slice : slices) {

        crc = Extend(crc, slice.get_data(), slice.get_size());

    }

    return crc;

}

} // namespace crc32c

} // namespace doris