cubefs

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/*
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 *
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 * Copyright 2018 gRPC 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 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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 *
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 */
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// Package grpcrand implements math/rand functions in a concurrent-safe way
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// with a global random source, independent of math/rand's global source.
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package grpcrand
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import (
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	"math/rand"
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	"sync"
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	"time"
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)
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var (
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	r  = rand.New(rand.NewSource(time.Now().UnixNano()))
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	mu sync.Mutex
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)
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// Int63n implements rand.Int63n on the grpcrand global source.
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func Int63n(n int64) int64 {
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	mu.Lock()
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	res := r.Int63n(n)
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	mu.Unlock()
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	return res
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}
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// Intn implements rand.Intn on the grpcrand global source.
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func Intn(n int) int {
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	mu.Lock()
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	res := r.Intn(n)
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	mu.Unlock()
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	return res
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}
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// Float64 implements rand.Float64 on the grpcrand global source.
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func Float64() float64 {
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	mu.Lock()
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	res := r.Float64()
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	mu.Unlock()
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	return res
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}
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