1/*
2 *
3 * Copyright 2018 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19// Package grpcrand implements math/rand functions in a concurrent-safe way
20// with a global random source, independent of math/rand's global source.
21package grpcrand
22
23import (
24	"math/rand"
25	"sync"
26	"time"
27)
28
29var (
30	r  = rand.New(rand.NewSource(time.Now().UnixNano()))
31	mu sync.Mutex
32)
33
34// Int63n implements rand.Int63n on the grpcrand global source.
35func Int63n(n int64) int64 {
36	mu.Lock()
37	res := r.Int63n(n)
38	mu.Unlock()
39	return res
40}
41
42// Intn implements rand.Intn on the grpcrand global source.
43func Intn(n int) int {
44	mu.Lock()
45	res := r.Intn(n)
46	mu.Unlock()
47	return res
48}
49
50// Float64 implements rand.Float64 on the grpcrand global source.
51func Float64() float64 {
52	mu.Lock()
53	res := r.Float64()
54	mu.Unlock()
55	return res
56}
57