1 // Copyright 2020 The gVisor Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 15 package stack
16 17 import (
18 "math/rand"
19 20 "gvisor.dev/gvisor/pkg/sync"
21 )
22 23 // lockedRandomSource provides a threadsafe rand.Source.
24 type lockedRandomSource struct {
25 mu sync.Mutex
26 src rand.Source
27 }
28 29 func (r *lockedRandomSource) Int63() (n int64) {
30 r.mu.Lock()
31 n = r.src.Int63()
32 r.mu.Unlock()
33 return n
34 }
35 36 func (r *lockedRandomSource) Seed(seed int64) {
37 r.mu.Lock()
38 r.src.Seed(seed)
39 r.mu.Unlock()
40 }
41