mirror of
https://github.com/cubefs/cubefs.git
synced 2026-08-02 02:00:56 +00:00
47 lines
1.3 KiB
Go
47 lines
1.3 KiB
Go
// Copyright 2023 The CubeFS Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
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// implied. See the License for the specific language governing
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// permissions and limitations under the License.
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package util
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type BloomFilter struct {
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bits []uint8
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hashFunc []func(data []byte) uint64
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}
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func NewBloomFilter(size uint64, hashFunc ...func(data []byte) uint64) *BloomFilter {
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return &BloomFilter{
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bits: make([]uint8, size),
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hashFunc: hashFunc,
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}
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}
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func (bf *BloomFilter) Add(data []byte) {
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for _, hashFunc := range bf.hashFunc {
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hash := hashFunc(data)
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index := hash % uint64(len(bf.bits))
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bf.bits[index/8] |= 1 << (index % 8)
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}
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}
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func (bf *BloomFilter) Contains(data []byte) bool {
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for _, hashFunc := range bf.hashFunc {
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hash := hashFunc(data)
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index := hash % uint64(len(bf.bits))
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if bf.bits[index/8]&(1<<(index%8)) == 0 {
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return false
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}
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}
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return true
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}
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