53 lines
1.8 KiB
Go
53 lines
1.8 KiB
Go
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// Copyright (c) 2016 Uber Technologies, Inc.
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package utils
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import (
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"math/rand"
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"sync"
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)
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// lockedSource allows a random number generator to be used by multiple goroutines concurrently.
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// The code is very similar to math/rand.lockedSource, which is unfortunately not exposed.
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type lockedSource struct {
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mut sync.Mutex
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src rand.Source
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}
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// NewRand returns a rand.Rand that is threadsafe.
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func NewRand(seed int64) *rand.Rand {
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return rand.New(&lockedSource{src: rand.NewSource(seed)})
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}
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func (r *lockedSource) Int63() (n int64) {
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r.mut.Lock()
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n = r.src.Int63()
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r.mut.Unlock()
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return
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}
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// Seed implements Seed() of Source
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func (r *lockedSource) Seed(seed int64) {
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r.mut.Lock()
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r.src.Seed(seed)
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r.mut.Unlock()
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}
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