zhjwpku commented on code in PR #238: URL: https://github.com/apache/iceberg-cpp/pull/238#discussion_r2434377302
########## src/iceberg/util/bucket_util.h: ########## @@ -0,0 +1,61 @@ +/* + * 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. + */ + +#pragma once + +#include <cstdint> +#include <span> + +#include "iceberg/expression/literal.h" +#include "iceberg/iceberg_export.h" +#include "iceberg/result.h" + +namespace iceberg { + +class ICEBERG_EXPORT BucketUtils { + public: + /// \brief Hash a 32-bit integer using MurmurHash3 and return a 32-bit hash value. + /// \param value The input integer to hash. + /// \note Integer and long hash results must be identical for all integer values. This + /// ensures that schema evolution does not change bucket partition values if integer + /// types are promoted. + /// \return A 32-bit hash value. + static inline int32_t HashInt(int32_t value) { + return HashLong(static_cast<int64_t>(value)); + } + + /// \brief Hash a 64-bit integer using MurmurHash3 and return a 32-bit hash value. + /// \param value The input long to hash. + /// \return A 32-bit hash value. + static int32_t HashLong(int64_t value); + + /// \brief Hash a byte array using MurmurHash3 and return a 32-bit hash value. + /// \param bytes The input byte array to hash. + /// \return A 32-bit hash value. + static int32_t HashBytes(std::span<const uint8_t> bytes); + + /// \brief Compute the bucket index for a given literal and number of buckets. + /// \param literal The input literal to hash. + /// \param num_buckets The number of buckets to hash into. + /// \return A Result containing the bucket index or an error. + /// The bucket index is in the range [0, num_buckets - 1]. + static Result<Literal> BucketIndex(const Literal& literal, int32_t num_buckets); Review Comment: Reasonable, done. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
