github.com/whtcorpsinc/milevadb-prod@v0.0.0-20211104133533-f57f4be3b597/soliton/mvmap/fnv.go (about)

     1  // Copyright 2011 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Copyright 2020 WHTCORPS INC
     6  //
     7  // Licensed under the Apache License, Version 2.0 (the "License");
     8  // you may not use this file except in compliance with the License.
     9  // You may obtain a copy of the License at
    10  //
    11  //     http://www.apache.org/licenses/LICENSE-2.0
    12  //
    13  // Unless required by applicable law or agreed to in writing, software
    14  // distributed under the License is distributed on an "AS IS" BASIS,
    15  // See the License for the specific language governing permissions and
    16  // limitations under the License.
    17  
    18  package mvmap
    19  
    20  const (
    21  	offset64 uint64 = 14695981039346656037
    22  	prime64  uint64 = 1099511628211
    23  )
    24  
    25  // fnvHash64 is ported from go library, which is thread-safe.
    26  func fnvHash64(data []byte) uint64 {
    27  	hash := offset64
    28  	for _, c := range data {
    29  		hash *= prime64
    30  		hash ^= uint64(c)
    31  	}
    32  	return hash
    33  }