libs/common: refactor libs/common 2 (#4231)

* libs/common: refactor libs/common 2

- move random function to there own pkg

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* change imports and usage throughout repo

* fix goimports

* add changelog entry
This commit is contained in:
Marko
2019-12-10 18:38:34 +01:00
committed by GitHub
parent dfebac86f7
commit afc4d7a61f
55 changed files with 221 additions and 196 deletions
+3 -1
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@@ -6,6 +6,8 @@ import (
"regexp"
"strings"
"sync"
"github.com/tendermint/tendermint/libs/rand"
)
// BitArray is a thread-safe implementation of a bit array.
@@ -250,7 +252,7 @@ func (bA *BitArray) PickRandom() (int, bool) {
return 0, false
}
return trueIndices[RandIntn(len(trueIndices))], true
return trueIndices[rand.RandIntn(len(trueIndices))], true
}
func (bA *BitArray) getTrueIndices() []int {
+3 -1
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@@ -8,10 +8,12 @@ import (
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"github.com/tendermint/tendermint/libs/rand"
)
func randBitArray(bits int) (*BitArray, []byte) {
src := RandBytes((bits + 7) / 8)
src := rand.RandBytes((bits + 7) / 8)
bA := NewBitArray(bits)
for i := 0; i < len(src); i++ {
for j := 0; j < 8; j++ {
-306
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@@ -1,306 +0,0 @@
package common
import (
crand "crypto/rand"
mrand "math/rand"
"sync"
"time"
)
const (
strChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" // 62 characters
)
// Rand is a prng, that is seeded with OS randomness.
// The OS randomness is obtained from crypto/rand, however none of the provided
// methods are suitable for cryptographic usage.
// They all utilize math/rand's prng internally.
//
// All of the methods here are suitable for concurrent use.
// This is achieved by using a mutex lock on all of the provided methods.
type Rand struct {
sync.Mutex
rand *mrand.Rand
}
var grand *Rand
func init() {
grand = NewRand()
grand.init()
}
func NewRand() *Rand {
rand := &Rand{}
rand.init()
return rand
}
func (r *Rand) init() {
bz := cRandBytes(8)
var seed uint64
for i := 0; i < 8; i++ {
seed |= uint64(bz[i])
seed <<= 8
}
r.reset(int64(seed))
}
func (r *Rand) reset(seed int64) {
r.rand = mrand.New(mrand.NewSource(seed))
}
//----------------------------------------
// Global functions
func Seed(seed int64) {
grand.Seed(seed)
}
func RandStr(length int) string {
return grand.Str(length)
}
func RandUint16() uint16 {
return grand.Uint16()
}
func RandUint32() uint32 {
return grand.Uint32()
}
func RandUint64() uint64 {
return grand.Uint64()
}
func RandUint() uint {
return grand.Uint()
}
func RandInt16() int16 {
return grand.Int16()
}
func RandInt32() int32 {
return grand.Int32()
}
func RandInt64() int64 {
return grand.Int64()
}
func RandInt() int {
return grand.Int()
}
func RandInt31() int32 {
return grand.Int31()
}
func RandInt31n(n int32) int32 {
return grand.Int31n(n)
}
func RandInt63() int64 {
return grand.Int63()
}
func RandInt63n(n int64) int64 {
return grand.Int63n(n)
}
func RandBool() bool {
return grand.Bool()
}
func RandFloat32() float32 {
return grand.Float32()
}
func RandFloat64() float64 {
return grand.Float64()
}
func RandTime() time.Time {
return grand.Time()
}
func RandBytes(n int) []byte {
return grand.Bytes(n)
}
func RandIntn(n int) int {
return grand.Intn(n)
}
func RandPerm(n int) []int {
return grand.Perm(n)
}
//----------------------------------------
// Rand methods
func (r *Rand) Seed(seed int64) {
r.Lock()
r.reset(seed)
r.Unlock()
}
// Str constructs a random alphanumeric string of given length.
func (r *Rand) Str(length int) string {
chars := []byte{}
MAIN_LOOP:
for {
val := r.Int63()
for i := 0; i < 10; i++ {
v := int(val & 0x3f) // rightmost 6 bits
if v >= 62 { // only 62 characters in strChars
val >>= 6
continue
} else {
chars = append(chars, strChars[v])
if len(chars) == length {
break MAIN_LOOP
}
val >>= 6
}
}
}
return string(chars)
}
func (r *Rand) Uint16() uint16 {
return uint16(r.Uint32() & (1<<16 - 1))
}
func (r *Rand) Uint32() uint32 {
r.Lock()
u32 := r.rand.Uint32()
r.Unlock()
return u32
}
func (r *Rand) Uint64() uint64 {
return uint64(r.Uint32())<<32 + uint64(r.Uint32())
}
func (r *Rand) Uint() uint {
r.Lock()
i := r.rand.Int()
r.Unlock()
return uint(i)
}
func (r *Rand) Int16() int16 {
return int16(r.Uint32() & (1<<16 - 1))
}
func (r *Rand) Int32() int32 {
return int32(r.Uint32())
}
func (r *Rand) Int64() int64 {
return int64(r.Uint64())
}
func (r *Rand) Int() int {
r.Lock()
i := r.rand.Int()
r.Unlock()
return i
}
func (r *Rand) Int31() int32 {
r.Lock()
i31 := r.rand.Int31()
r.Unlock()
return i31
}
func (r *Rand) Int31n(n int32) int32 {
r.Lock()
i31n := r.rand.Int31n(n)
r.Unlock()
return i31n
}
func (r *Rand) Int63() int64 {
r.Lock()
i63 := r.rand.Int63()
r.Unlock()
return i63
}
func (r *Rand) Int63n(n int64) int64 {
r.Lock()
i63n := r.rand.Int63n(n)
r.Unlock()
return i63n
}
func (r *Rand) Float32() float32 {
r.Lock()
f32 := r.rand.Float32()
r.Unlock()
return f32
}
func (r *Rand) Float64() float64 {
r.Lock()
f64 := r.rand.Float64()
r.Unlock()
return f64
}
func (r *Rand) Time() time.Time {
return time.Unix(int64(r.Uint64()), 0)
}
// Bytes returns n random bytes generated from the internal
// prng.
func (r *Rand) Bytes(n int) []byte {
// cRandBytes isn't guaranteed to be fast so instead
// use random bytes generated from the internal PRNG
bs := make([]byte, n)
for i := 0; i < len(bs); i++ {
bs[i] = byte(r.Int() & 0xFF)
}
return bs
}
// Intn returns, as an int, a uniform pseudo-random number in the range [0, n).
// It panics if n <= 0.
func (r *Rand) Intn(n int) int {
r.Lock()
i := r.rand.Intn(n)
r.Unlock()
return i
}
// Bool returns a uniformly random boolean
func (r *Rand) Bool() bool {
// See https://github.com/golang/go/issues/23804#issuecomment-365370418
// for reasoning behind computing like this
return r.Int63()%2 == 0
}
// Perm returns a pseudo-random permutation of n integers in [0, n).
func (r *Rand) Perm(n int) []int {
r.Lock()
perm := r.rand.Perm(n)
r.Unlock()
return perm
}
// NOTE: This relies on the os's random number generator.
// For real security, we should salt that with some seed.
// See github.com/tendermint/tendermint/crypto for a more secure reader.
func cRandBytes(numBytes int) []byte {
b := make([]byte, numBytes)
_, err := crand.Read(b)
if err != nil {
panic(err)
}
return b
}
-116
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@@ -1,116 +0,0 @@
package common
import (
"bytes"
"encoding/json"
"fmt"
mrand "math/rand"
"sync"
"testing"
"time"
"github.com/stretchr/testify/assert"
)
func TestRandStr(t *testing.T) {
l := 243
s := RandStr(l)
assert.Equal(t, l, len(s))
}
func TestRandBytes(t *testing.T) {
l := 243
b := RandBytes(l)
assert.Equal(t, l, len(b))
}
func TestRandIntn(t *testing.T) {
n := 243
for i := 0; i < 100; i++ {
x := RandIntn(n)
assert.True(t, x < n)
}
}
// Test to make sure that we never call math.rand().
// We do this by ensuring that outputs are deterministic.
func TestDeterminism(t *testing.T) {
var firstOutput string
// Set math/rand's seed for the sake of debugging this test.
// (It isn't strictly necessary).
mrand.Seed(1)
for i := 0; i < 100; i++ {
output := testThemAll()
if i == 0 {
firstOutput = output
} else if firstOutput != output {
t.Errorf("run #%d's output was different from first run.\nfirst: %v\nlast: %v",
i, firstOutput, output)
}
}
}
func testThemAll() string {
// Such determinism.
grand.reset(1)
// Use it.
out := new(bytes.Buffer)
perm := RandPerm(10)
blob, _ := json.Marshal(perm)
fmt.Fprintf(out, "perm: %s\n", blob)
fmt.Fprintf(out, "randInt: %d\n", RandInt())
fmt.Fprintf(out, "randUint: %d\n", RandUint())
fmt.Fprintf(out, "randIntn: %d\n", RandIntn(97))
fmt.Fprintf(out, "randInt31: %d\n", RandInt31())
fmt.Fprintf(out, "randInt32: %d\n", RandInt32())
fmt.Fprintf(out, "randInt63: %d\n", RandInt63())
fmt.Fprintf(out, "randInt64: %d\n", RandInt64())
fmt.Fprintf(out, "randUint32: %d\n", RandUint32())
fmt.Fprintf(out, "randUint64: %d\n", RandUint64())
return out.String()
}
func TestRngConcurrencySafety(t *testing.T) {
var wg sync.WaitGroup
for i := 0; i < 100; i++ {
wg.Add(1)
go func() {
defer wg.Done()
_ = RandUint64()
<-time.After(time.Millisecond * time.Duration(RandIntn(100)))
_ = RandPerm(3)
}()
}
wg.Wait()
}
func BenchmarkRandBytes10B(b *testing.B) {
benchmarkRandBytes(b, 10)
}
func BenchmarkRandBytes100B(b *testing.B) {
benchmarkRandBytes(b, 100)
}
func BenchmarkRandBytes1KiB(b *testing.B) {
benchmarkRandBytes(b, 1024)
}
func BenchmarkRandBytes10KiB(b *testing.B) {
benchmarkRandBytes(b, 10*1024)
}
func BenchmarkRandBytes100KiB(b *testing.B) {
benchmarkRandBytes(b, 100*1024)
}
func BenchmarkRandBytes1MiB(b *testing.B) {
benchmarkRandBytes(b, 1024*1024)
}
func benchmarkRandBytes(b *testing.B, n int) {
for i := 0; i < b.N; i++ {
_ = RandBytes(n)
}
b.ReportAllocs()
}
+4 -2
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@@ -10,12 +10,14 @@ import (
testing "testing"
"github.com/stretchr/testify/require"
"github.com/tendermint/tendermint/libs/rand"
)
func TestWriteFileAtomic(t *testing.T) {
var (
data = []byte(RandStr(RandIntn(2048)))
old = RandBytes(RandIntn(2048))
data = []byte(rand.RandStr(rand.RandIntn(2048)))
old = rand.RandBytes(rand.RandIntn(2048))
perm os.FileMode = 0600
)