mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-29 21:15:39 +00:00
35782f891d
Currently unused. (breaking up a bigger change) Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
597 lines
15 KiB
Go
597 lines
15 KiB
Go
// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package deephash
|
|
|
|
import (
|
|
"archive/tar"
|
|
"bufio"
|
|
"bytes"
|
|
"crypto/sha256"
|
|
"fmt"
|
|
"io"
|
|
"math"
|
|
"math/rand"
|
|
"reflect"
|
|
"runtime"
|
|
"testing"
|
|
"testing/quick"
|
|
"time"
|
|
"unsafe"
|
|
|
|
"go4.org/mem"
|
|
"inet.af/netaddr"
|
|
"tailscale.com/tailcfg"
|
|
"tailscale.com/types/dnstype"
|
|
"tailscale.com/types/ipproto"
|
|
"tailscale.com/types/key"
|
|
"tailscale.com/types/structs"
|
|
"tailscale.com/util/dnsname"
|
|
"tailscale.com/version"
|
|
"tailscale.com/wgengine/filter"
|
|
"tailscale.com/wgengine/router"
|
|
"tailscale.com/wgengine/wgcfg"
|
|
)
|
|
|
|
type appendBytes []byte
|
|
|
|
func (p appendBytes) AppendTo(b []byte) []byte {
|
|
return append(b, p...)
|
|
}
|
|
|
|
func TestHash(t *testing.T) {
|
|
type tuple [2]any
|
|
type iface struct{ X any }
|
|
type scalars struct {
|
|
I8 int8
|
|
I16 int16
|
|
I32 int32
|
|
I64 int64
|
|
I int
|
|
U8 uint8
|
|
U16 uint16
|
|
U32 uint32
|
|
U64 uint64
|
|
U uint
|
|
UP uintptr
|
|
F32 float32
|
|
F64 float64
|
|
C64 complex64
|
|
C128 complex128
|
|
}
|
|
type MyBool bool
|
|
type MyHeader tar.Header
|
|
var zeroFloat64 float64
|
|
tests := []struct {
|
|
in tuple
|
|
wantEq bool
|
|
}{
|
|
{in: tuple{false, true}, wantEq: false},
|
|
{in: tuple{true, true}, wantEq: true},
|
|
{in: tuple{false, false}, wantEq: true},
|
|
{
|
|
in: tuple{
|
|
scalars{-8, -16, -32, -64, -1234, 8, 16, 32, 64, 1234, 5678, 32.32, 64.64, 32 + 32i, 64 + 64i},
|
|
scalars{-8, -16, -32, -64, -1234, 8, 16, 32, 64, 1234, 5678, 32.32, 64.64, 32 + 32i, 64 + 64i},
|
|
},
|
|
wantEq: true,
|
|
},
|
|
{in: tuple{scalars{I8: math.MinInt8}, scalars{I8: math.MinInt8 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{I16: math.MinInt16}, scalars{I16: math.MinInt16 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{I32: math.MinInt32}, scalars{I32: math.MinInt32 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{I64: math.MinInt64}, scalars{I64: math.MinInt64 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{I: -1234}, scalars{I: -1234 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{U8: math.MaxUint8}, scalars{U8: math.MaxUint8 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{U16: math.MaxUint16}, scalars{U16: math.MaxUint16 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{U32: math.MaxUint32}, scalars{U32: math.MaxUint32 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{U64: math.MaxUint64}, scalars{U64: math.MaxUint64 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{U: 1234}, scalars{U: 1234 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{UP: 5678}, scalars{UP: 5678 / 2}}, wantEq: false},
|
|
{in: tuple{scalars{F32: 32.32}, scalars{F32: math.Nextafter32(32.32, 0)}}, wantEq: false},
|
|
{in: tuple{scalars{F64: 64.64}, scalars{F64: math.Nextafter(64.64, 0)}}, wantEq: false},
|
|
{in: tuple{scalars{F32: float32(math.NaN())}, scalars{F32: float32(math.NaN())}}, wantEq: true},
|
|
{in: tuple{scalars{F64: float64(math.NaN())}, scalars{F64: float64(math.NaN())}}, wantEq: true},
|
|
{in: tuple{scalars{C64: 32 + 32i}, scalars{C64: complex(math.Nextafter32(32, 0), 32)}}, wantEq: false},
|
|
{in: tuple{scalars{C128: 64 + 64i}, scalars{C128: complex(math.Nextafter(64, 0), 64)}}, wantEq: false},
|
|
{in: tuple{[]appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}, []appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}}, wantEq: true},
|
|
{in: tuple{[]appendBytes{{}, {0, 0, 0, 0, 0, 0, 0, 1}}, []appendBytes{{0, 0, 0, 0, 0, 0, 0, 1}, {}}}, wantEq: false},
|
|
{in: tuple{iface{MyBool(true)}, iface{MyBool(true)}}, wantEq: true},
|
|
{in: tuple{iface{true}, iface{MyBool(true)}}, wantEq: false},
|
|
{in: tuple{iface{MyHeader{}}, iface{MyHeader{}}}, wantEq: true},
|
|
{in: tuple{iface{MyHeader{}}, iface{tar.Header{}}}, wantEq: false},
|
|
{in: tuple{iface{&MyHeader{}}, iface{&MyHeader{}}}, wantEq: true},
|
|
{in: tuple{iface{&MyHeader{}}, iface{&tar.Header{}}}, wantEq: false},
|
|
{in: tuple{iface{[]map[string]MyBool{}}, iface{[]map[string]MyBool{}}}, wantEq: true},
|
|
{in: tuple{iface{[]map[string]bool{}}, iface{[]map[string]MyBool{}}}, wantEq: false},
|
|
{in: tuple{zeroFloat64, -zeroFloat64}, wantEq: false}, // Issue 4883 (false alarm)
|
|
{in: tuple{[]any(nil), 0.0}, wantEq: false}, // Issue 4883
|
|
{in: tuple{[]any(nil), uint8(0)}, wantEq: false}, // Issue 4883
|
|
{in: tuple{nil, nil}, wantEq: true}, // Issue 4883
|
|
{
|
|
in: func() tuple {
|
|
i1 := 1
|
|
i2 := 2
|
|
v1 := [3]*int{&i1, &i2, &i1}
|
|
v2 := [3]*int{&i1, &i2, &i2}
|
|
return tuple{v1, v2}
|
|
}(),
|
|
wantEq: false,
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
gotEq := Hash(tt.in[0]) == Hash(tt.in[1])
|
|
if gotEq != tt.wantEq {
|
|
t.Errorf("(Hash(%T %v) == Hash(%T %v)) = %v, want %v", tt.in[0], tt.in[0], tt.in[1], tt.in[1], gotEq, tt.wantEq)
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestDeepHash(t *testing.T) {
|
|
// v contains the types of values we care about for our current callers.
|
|
// Mostly we're just testing that we don't panic on handled types.
|
|
v := getVal()
|
|
|
|
hash1 := Hash(v)
|
|
t.Logf("hash: %v", hash1)
|
|
for i := 0; i < 20; i++ {
|
|
hash2 := Hash(getVal())
|
|
if hash1 != hash2 {
|
|
t.Error("second hash didn't match")
|
|
}
|
|
}
|
|
}
|
|
|
|
// Tests that we actually hash map elements. Whoops.
|
|
func TestIssue4868(t *testing.T) {
|
|
m1 := map[int]string{1: "foo"}
|
|
m2 := map[int]string{1: "bar"}
|
|
if Hash(m1) == Hash(m2) {
|
|
t.Error("bogus")
|
|
}
|
|
}
|
|
|
|
func TestIssue4871(t *testing.T) {
|
|
m1 := map[string]string{"": "", "x": "foo"}
|
|
m2 := map[string]string{}
|
|
if h1, h2 := Hash(m1), Hash(m2); h1 == h2 {
|
|
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
|
|
}
|
|
}
|
|
|
|
func TestNilVsEmptymap(t *testing.T) {
|
|
m1 := map[string]string(nil)
|
|
m2 := map[string]string{}
|
|
if h1, h2 := Hash(m1), Hash(m2); h1 == h2 {
|
|
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
|
|
}
|
|
}
|
|
|
|
func TestMapFraming(t *testing.T) {
|
|
m1 := map[string]string{"foo": "", "fo": "o"}
|
|
m2 := map[string]string{}
|
|
if h1, h2 := Hash(m1), Hash(m2); h1 == h2 {
|
|
t.Errorf("bogus: h1=%x, h2=%x", h1, h2)
|
|
}
|
|
}
|
|
|
|
func TestQuick(t *testing.T) {
|
|
initSeed()
|
|
err := quick.Check(func(v, w map[string]string) bool {
|
|
return (Hash(v) == Hash(w)) == reflect.DeepEqual(v, w)
|
|
}, &quick.Config{MaxCount: 1000, Rand: rand.New(rand.NewSource(int64(seed)))})
|
|
if err != nil {
|
|
t.Fatalf("seed=%v, err=%v", seed, err)
|
|
}
|
|
}
|
|
|
|
func getVal() []any {
|
|
return []any{
|
|
&wgcfg.Config{
|
|
Name: "foo",
|
|
Addresses: []netaddr.IPPrefix{netaddr.IPPrefixFrom(netaddr.IPFrom16([16]byte{3: 3}), 5)},
|
|
Peers: []wgcfg.Peer{
|
|
{
|
|
PublicKey: key.NodePublic{},
|
|
},
|
|
},
|
|
},
|
|
&router.Config{
|
|
Routes: []netaddr.IPPrefix{
|
|
netaddr.MustParseIPPrefix("1.2.3.0/24"),
|
|
netaddr.MustParseIPPrefix("1234::/64"),
|
|
},
|
|
},
|
|
map[dnsname.FQDN][]netaddr.IP{
|
|
dnsname.FQDN("a."): {netaddr.MustParseIP("1.2.3.4"), netaddr.MustParseIP("4.3.2.1")},
|
|
dnsname.FQDN("b."): {netaddr.MustParseIP("8.8.8.8"), netaddr.MustParseIP("9.9.9.9")},
|
|
dnsname.FQDN("c."): {netaddr.MustParseIP("6.6.6.6"), netaddr.MustParseIP("7.7.7.7")},
|
|
dnsname.FQDN("d."): {netaddr.MustParseIP("6.7.6.6"), netaddr.MustParseIP("7.7.7.8")},
|
|
dnsname.FQDN("e."): {netaddr.MustParseIP("6.8.6.6"), netaddr.MustParseIP("7.7.7.9")},
|
|
dnsname.FQDN("f."): {netaddr.MustParseIP("6.9.6.6"), netaddr.MustParseIP("7.7.7.0")},
|
|
},
|
|
map[dnsname.FQDN][]netaddr.IPPort{
|
|
dnsname.FQDN("a."): {netaddr.MustParseIPPort("1.2.3.4:11"), netaddr.MustParseIPPort("4.3.2.1:22")},
|
|
dnsname.FQDN("b."): {netaddr.MustParseIPPort("8.8.8.8:11"), netaddr.MustParseIPPort("9.9.9.9:22")},
|
|
dnsname.FQDN("c."): {netaddr.MustParseIPPort("8.8.8.8:12"), netaddr.MustParseIPPort("9.9.9.9:23")},
|
|
dnsname.FQDN("d."): {netaddr.MustParseIPPort("8.8.8.8:13"), netaddr.MustParseIPPort("9.9.9.9:24")},
|
|
dnsname.FQDN("e."): {netaddr.MustParseIPPort("8.8.8.8:14"), netaddr.MustParseIPPort("9.9.9.9:25")},
|
|
},
|
|
map[key.DiscoPublic]bool{
|
|
key.DiscoPublicFromRaw32(mem.B([]byte{1: 1, 31: 0})): true,
|
|
key.DiscoPublicFromRaw32(mem.B([]byte{1: 2, 31: 0})): false,
|
|
key.DiscoPublicFromRaw32(mem.B([]byte{1: 3, 31: 0})): true,
|
|
key.DiscoPublicFromRaw32(mem.B([]byte{1: 4, 31: 0})): false,
|
|
},
|
|
&tailcfg.MapResponse{
|
|
DERPMap: &tailcfg.DERPMap{
|
|
Regions: map[int]*tailcfg.DERPRegion{
|
|
1: {
|
|
RegionID: 1,
|
|
RegionCode: "foo",
|
|
Nodes: []*tailcfg.DERPNode{
|
|
{
|
|
Name: "n1",
|
|
RegionID: 1,
|
|
HostName: "foo.com",
|
|
},
|
|
{
|
|
Name: "n2",
|
|
RegionID: 1,
|
|
HostName: "bar.com",
|
|
},
|
|
},
|
|
},
|
|
},
|
|
},
|
|
DNSConfig: &tailcfg.DNSConfig{
|
|
Resolvers: []*dnstype.Resolver{
|
|
{Addr: "10.0.0.1"},
|
|
},
|
|
},
|
|
PacketFilter: []tailcfg.FilterRule{
|
|
{
|
|
SrcIPs: []string{"1.2.3.4"},
|
|
DstPorts: []tailcfg.NetPortRange{
|
|
{
|
|
IP: "1.2.3.4/32",
|
|
Ports: tailcfg.PortRange{First: 1, Last: 2},
|
|
},
|
|
},
|
|
},
|
|
},
|
|
Peers: []*tailcfg.Node{
|
|
{
|
|
ID: 1,
|
|
},
|
|
{
|
|
ID: 2,
|
|
},
|
|
},
|
|
UserProfiles: []tailcfg.UserProfile{
|
|
{ID: 1, LoginName: "foo@bar.com"},
|
|
{ID: 2, LoginName: "bar@foo.com"},
|
|
},
|
|
},
|
|
filter.Match{
|
|
IPProto: []ipproto.Proto{1, 2, 3},
|
|
},
|
|
}
|
|
}
|
|
|
|
func TestTypeIsRecursive(t *testing.T) {
|
|
type RecursiveStruct struct {
|
|
v *RecursiveStruct
|
|
}
|
|
type RecursiveChan chan *RecursiveChan
|
|
|
|
tests := []struct {
|
|
val any
|
|
want bool
|
|
}{
|
|
{val: 42, want: false},
|
|
{val: "string", want: false},
|
|
{val: 1 + 2i, want: false},
|
|
{val: struct{}{}, want: false},
|
|
{val: (*RecursiveStruct)(nil), want: true},
|
|
{val: RecursiveStruct{}, want: true},
|
|
{val: time.Unix(0, 0), want: false},
|
|
{val: structs.Incomparable{}, want: false}, // ignore its [0]func()
|
|
{val: tailcfg.NetPortRange{}, want: false}, // uses structs.Incomparable
|
|
{val: (*tailcfg.Node)(nil), want: false},
|
|
{val: map[string]bool{}, want: false},
|
|
{val: func() {}, want: false},
|
|
{val: make(chan int), want: false},
|
|
{val: unsafe.Pointer(nil), want: false},
|
|
{val: make(RecursiveChan), want: true},
|
|
{val: make(chan int), want: false},
|
|
}
|
|
for _, tt := range tests {
|
|
got := typeIsRecursive(reflect.TypeOf(tt.val))
|
|
if got != tt.want {
|
|
t.Errorf("for type %T: got %v, want %v", tt.val, got, tt.want)
|
|
}
|
|
}
|
|
}
|
|
|
|
type IntThenByte struct {
|
|
i int
|
|
b byte
|
|
}
|
|
|
|
type TwoInts struct{ a, b int }
|
|
|
|
type IntIntByteInt struct {
|
|
i1, i2 int32
|
|
b byte // padding after
|
|
i3 int32
|
|
}
|
|
|
|
func TestCanMemHash(t *testing.T) {
|
|
tests := []struct {
|
|
val any
|
|
want bool
|
|
}{
|
|
{true, true},
|
|
{uint(1), true},
|
|
{uint8(1), true},
|
|
{uint16(1), true},
|
|
{uint32(1), true},
|
|
{uint64(1), true},
|
|
{uintptr(1), true},
|
|
{int(1), true},
|
|
{int8(1), true},
|
|
{int16(1), true},
|
|
{int32(1), true},
|
|
{int64(1), true},
|
|
{float32(1), true},
|
|
{float64(1), true},
|
|
{complex64(1), true},
|
|
{complex128(1), true},
|
|
{[32]byte{}, true},
|
|
{func() {}, false},
|
|
{make(chan int), false},
|
|
{struct{ io.Writer }{nil}, false},
|
|
{unsafe.Pointer(nil), false},
|
|
{new(int), false},
|
|
{TwoInts{}, true},
|
|
{[4]TwoInts{}, true},
|
|
{IntThenByte{}, false},
|
|
{[4]IntThenByte{}, false},
|
|
{tailcfg.PortRange{}, true},
|
|
{int16(0), true},
|
|
{struct {
|
|
_ int
|
|
_ int
|
|
}{}, true},
|
|
{struct {
|
|
_ int
|
|
_ uint8
|
|
_ int
|
|
}{}, false}, // gap
|
|
{
|
|
struct {
|
|
_ structs.Incomparable // if not last, zero-width
|
|
x int
|
|
}{},
|
|
true,
|
|
},
|
|
{
|
|
struct {
|
|
x int
|
|
_ structs.Incomparable // zero-width last: has space, can't memhash
|
|
}{},
|
|
false,
|
|
}}
|
|
for _, tt := range tests {
|
|
got := canMemHash(reflect.TypeOf(tt.val))
|
|
if got != tt.want {
|
|
t.Errorf("for type %T: got %v, want %v", tt.val, got, tt.want)
|
|
}
|
|
}
|
|
}
|
|
|
|
var sink = Hash("foo")
|
|
|
|
func BenchmarkHash(b *testing.B) {
|
|
b.ReportAllocs()
|
|
v := getVal()
|
|
for i := 0; i < b.N; i++ {
|
|
sink = Hash(v)
|
|
}
|
|
}
|
|
|
|
func ptrTo[T any](v T) *T { return &v }
|
|
|
|
// filterRules is a packet filter that has both everything populated (in its
|
|
// first element) and also a few entries that are the typical shape for regular
|
|
// packet filters as sent to clients.
|
|
var filterRules = []tailcfg.FilterRule{
|
|
{
|
|
SrcIPs: []string{"*", "10.1.3.4/32", "10.0.0.0/24"},
|
|
SrcBits: []int{1, 2, 3},
|
|
DstPorts: []tailcfg.NetPortRange{{
|
|
IP: "1.2.3.4/32",
|
|
Bits: ptrTo(32),
|
|
Ports: tailcfg.PortRange{First: 1, Last: 2},
|
|
}},
|
|
IPProto: []int{1, 2, 3, 4},
|
|
CapGrant: []tailcfg.CapGrant{{
|
|
Dsts: []netaddr.IPPrefix{netaddr.MustParseIPPrefix("1.2.3.4/32")},
|
|
Caps: []string{"foo"},
|
|
}},
|
|
},
|
|
{
|
|
SrcIPs: []string{"foooooooooo"},
|
|
DstPorts: []tailcfg.NetPortRange{{
|
|
IP: "baaaaaarrrrr",
|
|
Ports: tailcfg.PortRange{First: 1, Last: 2},
|
|
}},
|
|
},
|
|
{
|
|
SrcIPs: []string{"foooooooooo"},
|
|
DstPorts: []tailcfg.NetPortRange{{
|
|
IP: "baaaaaarrrrr",
|
|
Ports: tailcfg.PortRange{First: 1, Last: 2},
|
|
}},
|
|
},
|
|
{
|
|
SrcIPs: []string{"foooooooooo"},
|
|
DstPorts: []tailcfg.NetPortRange{{
|
|
IP: "baaaaaarrrrr",
|
|
Ports: tailcfg.PortRange{First: 1, Last: 2},
|
|
}},
|
|
},
|
|
}
|
|
|
|
func BenchmarkHashPacketFilter(b *testing.B) {
|
|
b.ReportAllocs()
|
|
|
|
for i := 0; i < b.N; i++ {
|
|
sink = Hash(filterRules)
|
|
}
|
|
}
|
|
|
|
func TestHashMapAcyclic(t *testing.T) {
|
|
m := map[int]string{}
|
|
for i := 0; i < 100; i++ {
|
|
m[i] = fmt.Sprint(i)
|
|
}
|
|
got := map[string]bool{}
|
|
|
|
var buf bytes.Buffer
|
|
bw := bufio.NewWriter(&buf)
|
|
|
|
ti := getTypeInfo(reflect.TypeOf(m))
|
|
|
|
for i := 0; i < 20; i++ {
|
|
v := reflect.ValueOf(m)
|
|
buf.Reset()
|
|
bw.Reset(&buf)
|
|
h := &hasher{bw: bw}
|
|
h.hashMap(v, ti, false)
|
|
if got[string(buf.Bytes())] {
|
|
continue
|
|
}
|
|
got[string(buf.Bytes())] = true
|
|
}
|
|
if len(got) != 1 {
|
|
t.Errorf("got %d results; want 1", len(got))
|
|
}
|
|
}
|
|
|
|
func TestPrintArray(t *testing.T) {
|
|
type T struct {
|
|
X [32]byte
|
|
}
|
|
x := T{X: [32]byte{1: 1, 31: 31}}
|
|
var got bytes.Buffer
|
|
bw := bufio.NewWriter(&got)
|
|
h := &hasher{bw: bw}
|
|
h.hashValue(reflect.ValueOf(x), false)
|
|
bw.Flush()
|
|
const want = "\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x1f"
|
|
if got := got.Bytes(); string(got) != want {
|
|
t.Errorf("wrong:\n got: %q\nwant: %q\n", got, want)
|
|
}
|
|
}
|
|
|
|
func BenchmarkHashMapAcyclic(b *testing.B) {
|
|
b.ReportAllocs()
|
|
m := map[int]string{}
|
|
for i := 0; i < 100; i++ {
|
|
m[i] = fmt.Sprint(i)
|
|
}
|
|
|
|
var buf bytes.Buffer
|
|
bw := bufio.NewWriter(&buf)
|
|
v := reflect.ValueOf(m)
|
|
ti := getTypeInfo(v.Type())
|
|
|
|
h := &hasher{bw: bw}
|
|
|
|
for i := 0; i < b.N; i++ {
|
|
buf.Reset()
|
|
bw.Reset(&buf)
|
|
h.hashMap(v, ti, false)
|
|
}
|
|
}
|
|
|
|
func BenchmarkTailcfgNode(b *testing.B) {
|
|
b.ReportAllocs()
|
|
|
|
node := new(tailcfg.Node)
|
|
for i := 0; i < b.N; i++ {
|
|
sink = Hash(node)
|
|
}
|
|
}
|
|
|
|
func TestExhaustive(t *testing.T) {
|
|
seen := make(map[Sum]bool)
|
|
for i := 0; i < 100000; i++ {
|
|
s := Hash(i)
|
|
if seen[s] {
|
|
t.Fatalf("hash collision %v", i)
|
|
}
|
|
seen[s] = true
|
|
}
|
|
}
|
|
|
|
// verify this doesn't loop forever, as it used to (Issue 2340)
|
|
func TestMapCyclicFallback(t *testing.T) {
|
|
type T struct {
|
|
M map[string]any
|
|
}
|
|
v := &T{
|
|
M: map[string]any{},
|
|
}
|
|
v.M["m"] = v.M
|
|
Hash(v)
|
|
}
|
|
|
|
func TestArrayAllocs(t *testing.T) {
|
|
if version.IsRace() {
|
|
t.Skip("skipping test under race detector")
|
|
}
|
|
|
|
// In theory, there should be no allocations. However, escape analysis on
|
|
// certain architectures fails to detect that certain cases do not escape.
|
|
// This discrepency currently affects sha256.digest.Sum.
|
|
// Measure the number of allocations in sha256 to ensure that Hash does
|
|
// not allocate on top of its usage of sha256.
|
|
// See https://golang.org/issue/48055.
|
|
var b []byte
|
|
h := sha256.New()
|
|
want := int(testing.AllocsPerRun(1000, func() {
|
|
b = h.Sum(b[:0])
|
|
}))
|
|
switch runtime.GOARCH {
|
|
case "amd64", "arm64":
|
|
want = 0 // ensure no allocations on popular architectures
|
|
}
|
|
|
|
type T struct {
|
|
X [32]byte
|
|
}
|
|
x := &T{X: [32]byte{1: 1, 2: 2, 3: 3, 4: 4}}
|
|
got := int(testing.AllocsPerRun(1000, func() {
|
|
sink = Hash(x)
|
|
}))
|
|
if got > want {
|
|
t.Errorf("allocs = %v; want %v", got, want)
|
|
}
|
|
}
|
|
|
|
func BenchmarkHashArray(b *testing.B) {
|
|
b.ReportAllocs()
|
|
type T struct {
|
|
X [32]byte
|
|
}
|
|
x := &T{X: [32]byte{1: 1, 2: 2, 3: 3, 4: 4}}
|
|
|
|
for i := 0; i < b.N; i++ {
|
|
sink = Hash(x)
|
|
}
|
|
}
|