libgo/go/net/writev_test.go

   1 // Copyright 2016 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // +build !js
   6
   7 package net
   8
   9 import (
  10         "bytes"
  11         "fmt"
  12         "internal/poll"
  13         "io"
  14         "io/ioutil"
  15         "reflect"
  16         "runtime"
  17         "sync"
  18         "testing"
  19 )
  20
  21 func TestBuffers_read(t *testing.T) {
  22         const story = "once upon a time in Gopherland ... "
  23         buffers := Buffers{
  24                 []byte("once "),
  25                 []byte("upon "),
  26                 []byte("a "),
  27                 []byte("time "),
  28                 []byte("in "),
  29                 []byte("Gopherland ... "),
  30         }
  31         got, err := ioutil.ReadAll(&buffers)
  32         if err != nil {
  33                 t.Fatal(err)
  34         }
  35         if string(got) != story {
  36                 t.Errorf("read %q; want %q", got, story)
  37         }
  38         if len(buffers) != 0 {
  39                 t.Errorf("len(buffers) = %d; want 0", len(buffers))
  40         }
  41 }
  42
  43 func TestBuffers_consume(t *testing.T) {
  44         tests := []struct {
  45                 in      Buffers
  46                 consume int64
  47                 want    Buffers
  48         }{
  49                 {
  50                         in:      Buffers{[]byte("foo"), []byte("bar")},
  51                         consume: 0,
  52                         want:    Buffers{[]byte("foo"), []byte("bar")},
  53                 },
  54                 {
  55                         in:      Buffers{[]byte("foo"), []byte("bar")},
  56                         consume: 2,
  57                         want:    Buffers{[]byte("o"), []byte("bar")},
  58                 },
  59                 {
  60                         in:      Buffers{[]byte("foo"), []byte("bar")},
  61                         consume: 3,
  62                         want:    Buffers{[]byte("bar")},
  63                 },
  64                 {
  65                         in:      Buffers{[]byte("foo"), []byte("bar")},
  66                         consume: 4,
  67                         want:    Buffers{[]byte("ar")},
  68                 },
  69                 {
  70                         in:      Buffers{nil, nil, nil, []byte("bar")},
  71                         consume: 1,
  72                         want:    Buffers{[]byte("ar")},
  73                 },
  74                 {
  75                         in:      Buffers{nil, nil, nil, []byte("foo")},
  76                         consume: 0,
  77                         want:    Buffers{[]byte("foo")},
  78                 },
  79                 {
  80                         in:      Buffers{nil, nil, nil},
  81                         consume: 0,
  82                         want:    Buffers{},
  83                 },
  84         }
  85         for i, tt := range tests {
  86                 in := tt.in
  87                 in.consume(tt.consume)
  88                 if !reflect.DeepEqual(in, tt.want) {
  89                         t.Errorf("%d. after consume(%d) = %+v, want %+v", i, tt.consume, in, tt.want)
  90                 }
  91         }
  92 }
  93
  94 func TestBuffers_WriteTo(t *testing.T) {
  95         for _, name := range []string{"WriteTo", "Copy"} {
  96                 for _, size := range []int{0, 10, 1023, 1024, 1025} {
  97                         t.Run(fmt.Sprintf("%s/%d", name, size), func(t *testing.T) {
  98                                 testBuffer_writeTo(t, size, name == "Copy")
  99                         })
 100                 }
 101         }
 102 }
 103
 104 func testBuffer_writeTo(t *testing.T, chunks int, useCopy bool) {
 105         oldHook := poll.TestHookDidWritev
 106         defer func() { poll.TestHookDidWritev = oldHook }()
 107         var writeLog struct {
 108                 sync.Mutex
 109                 log []int
 110         }
 111         poll.TestHookDidWritev = func(size int) {
 112                 writeLog.Lock()
 113                 writeLog.log = append(writeLog.log, size)
 114                 writeLog.Unlock()
 115         }
 116         var want bytes.Buffer
 117         for i := 0; i < chunks; i++ {
 118                 want.WriteByte(byte(i))
 119         }
 120
 121         withTCPConnPair(t, func(c *TCPConn) error {
 122                 buffers := make(Buffers, chunks)
 123                 for i := range buffers {
 124                         buffers[i] = want.Bytes()[i : i+1]
 125                 }
 126                 var n int64
 127                 var err error
 128                 if useCopy {
 129                         n, err = io.Copy(c, &buffers)
 130                 } else {
 131                         n, err = buffers.WriteTo(c)
 132                 }
 133                 if err != nil {
 134                         return err
 135                 }
 136                 if len(buffers) != 0 {
 137                         return fmt.Errorf("len(buffers) = %d; want 0", len(buffers))
 138                 }
 139                 if n != int64(want.Len()) {
 140                         return fmt.Errorf("Buffers.WriteTo returned %d; want %d", n, want.Len())
 141                 }
 142                 return nil
 143         }, func(c *TCPConn) error {
 144                 all, err := ioutil.ReadAll(c)
 145                 if !bytes.Equal(all, want.Bytes()) || err != nil {
 146                         return fmt.Errorf("client read %q, %v; want %q, nil", all, err, want.Bytes())
 147                 }
 148
 149                 writeLog.Lock() // no need to unlock
 150                 var gotSum int
 151                 for _, v := range writeLog.log {
 152                         gotSum += v
 153                 }
 154
 155                 var wantSum int
 156                 switch runtime.GOOS {
 157                 case "android", "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd":
 158                         var wantMinCalls int
 159                         wantSum = want.Len()
 160                         v := chunks
 161                         for v > 0 {
 162                                 wantMinCalls++
 163                                 v -= 1024
 164                         }
 165                         if len(writeLog.log) < wantMinCalls {
 166                                 t.Errorf("write calls = %v < wanted min %v", len(writeLog.log), wantMinCalls)
 167                         }
 168                 case "windows":
 169                         var wantCalls int
 170                         wantSum = want.Len()
 171                         if wantSum > 0 {
 172                                 wantCalls = 1 // windows will always do 1 syscall, unless sending empty buffer
 173                         }
 174                         if len(writeLog.log) != wantCalls {
 175                                 t.Errorf("write calls = %v; want %v", len(writeLog.log), wantCalls)
 176                         }
 177                 }
 178                 if gotSum != wantSum {
 179                         t.Errorf("writev call sum  = %v; want %v", gotSum, wantSum)
 180                 }
 181                 return nil
 182         })
 183 }
 184
 185 func TestWritevError(t *testing.T) {
 186         if runtime.GOOS == "windows" {
 187                 t.Skipf("skipping the test: windows does not have problem sending large chunks of data")
 188         }
 189
 190         ln, err := newLocalListener("tcp")
 191         if err != nil {
 192                 t.Fatal(err)
 193         }
 194         defer ln.Close()
 195
 196         ch := make(chan Conn, 1)
 197         go func() {
 198                 defer close(ch)
 199                 c, err := ln.Accept()
 200                 if err != nil {
 201                         t.Error(err)
 202                         return
 203                 }
 204                 ch <- c
 205         }()
 206         c1, err := Dial("tcp", ln.Addr().String())
 207         if err != nil {
 208                 t.Fatal(err)
 209         }
 210         defer c1.Close()
 211         c2 := <-ch
 212         if c2 == nil {
 213                 t.Fatal("no server side connection")
 214         }
 215         c2.Close()
 216
 217         // 1 GB of data should be enough to notice the connection is gone.
 218         // Just a few bytes is not enough.
 219         // Arrange to reuse the same 1 MB buffer so that we don't allocate much.
 220         buf := make([]byte, 1<<20)
 221         buffers := make(Buffers, 1<<10)
 222         for i := range buffers {
 223                 buffers[i] = buf
 224         }
 225         if _, err := buffers.WriteTo(c1); err == nil {
 226                 t.Fatal("Buffers.WriteTo(closed conn) succeeded, want error")
 227         }
 228 }