mirror of
https://github.com/VictoriaMetrics/VictoriaMetrics.git
synced 2024-12-22 16:36:27 +01:00
43 lines
1.2 KiB
Go
43 lines
1.2 KiB
Go
|
// Copyright 2015 The Prometheus Authors
|
||
|
// Licensed 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.
|
||
|
|
||
|
package model
|
||
|
|
||
|
// Inline and byte-free variant of hash/fnv's fnv64a.
|
||
|
|
||
|
const (
|
||
|
offset64 = 14695981039346656037
|
||
|
prime64 = 1099511628211
|
||
|
)
|
||
|
|
||
|
// hashNew initializes a new fnv64a hash value.
|
||
|
func hashNew() uint64 {
|
||
|
return offset64
|
||
|
}
|
||
|
|
||
|
// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
|
||
|
func hashAdd(h uint64, s string) uint64 {
|
||
|
for i := 0; i < len(s); i++ {
|
||
|
h ^= uint64(s[i])
|
||
|
h *= prime64
|
||
|
}
|
||
|
return h
|
||
|
}
|
||
|
|
||
|
// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
|
||
|
func hashAddByte(h uint64, b byte) uint64 {
|
||
|
h ^= uint64(b)
|
||
|
h *= prime64
|
||
|
return h
|
||
|
}
|