43 lines
1.2 KiB
Go
43 lines
1.2 KiB
Go
// Copyright 2015 The Prometheus Authors
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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 implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package model
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// Inline and byte-free variant of hash/fnv's fnv64a.
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const (
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offset64 = 14695981039346656037
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prime64 = 1099511628211
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)
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// hashNew initializes a new fnv64a hash value.
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func hashNew() uint64 {
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return offset64
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}
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// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
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func hashAdd(h uint64, s string) uint64 {
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for i := 0; i < len(s); i++ {
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h ^= uint64(s[i])
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h *= prime64
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}
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return h
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}
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// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
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func hashAddByte(h uint64, b byte) uint64 {
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h ^= uint64(b)
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h *= prime64
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return h
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}
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