--- /dev/null
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !nacl
+// +build !plan9
+// +build !windows
+
+package os_test
+
+import (
+ "fmt"
+ "internal/poll"
+ "io"
+ "io/ioutil"
+ "math/rand"
+ "os"
+ "runtime"
+ "sync"
+ "testing"
+ "time"
+)
+
+func TestNonpollableDeadline(t *testing.T) {
+ // On BSD systems regular files seem to be pollable,
+ // so just run this test on Linux.
+ if runtime.GOOS != "linux" {
+ t.Skipf("skipping on %s", runtime.GOOS)
+ }
+
+ f, err := ioutil.TempFile("", "ostest")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer os.Remove(f.Name())
+ defer f.Close()
+ deadline := time.Now().Add(10 * time.Second)
+ if err := f.SetDeadline(deadline); err != os.ErrNoDeadline {
+ t.Errorf("SetDeadline on file returned %v, wanted %v", err, os.ErrNoDeadline)
+ }
+ if err := f.SetReadDeadline(deadline); err != os.ErrNoDeadline {
+ t.Errorf("SetReadDeadline on file returned %v, wanted %v", err, os.ErrNoDeadline)
+ }
+ if err := f.SetWriteDeadline(deadline); err != os.ErrNoDeadline {
+ t.Errorf("SetWriteDeadline on file returned %v, wanted %v", err, os.ErrNoDeadline)
+ }
+}
+
+// noDeadline is a zero time.Time value, which cancels a deadline.
+var noDeadline time.Time
+
+var readTimeoutTests = []struct {
+ timeout time.Duration
+ xerrs [2]error // expected errors in transition
+}{
+ // Tests that read deadlines work, even if there's data ready
+ // to be read.
+ {-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
+
+ {50 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
+}
+
+func TestReadTimeout(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ if _, err := w.Write([]byte("READ TIMEOUT TEST")); err != nil {
+ t.Fatal(err)
+ }
+
+ for i, tt := range readTimeoutTests {
+ if err := r.SetReadDeadline(time.Now().Add(tt.timeout)); err != nil {
+ t.Fatalf("#%d: %v", i, err)
+ }
+ var b [1]byte
+ for j, xerr := range tt.xerrs {
+ for {
+ n, err := r.Read(b[:])
+ if xerr != nil {
+ if !os.IsTimeout(err) {
+ t.Fatalf("#%d/%d: %v", i, j, err)
+ }
+ }
+ if err == nil {
+ time.Sleep(tt.timeout / 3)
+ continue
+ }
+ if n != 0 {
+ t.Fatalf("#%d/%d: read %d; want 0", i, j, n)
+ }
+ break
+ }
+ }
+ }
+}
+
+func TestReadTimeoutMustNotReturn(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ max := time.NewTimer(100 * time.Millisecond)
+ defer max.Stop()
+ ch := make(chan error)
+ go func() {
+ if err := r.SetDeadline(time.Now().Add(-5 * time.Second)); err != nil {
+ t.Error(err)
+ }
+ if err := r.SetWriteDeadline(time.Now().Add(-5 * time.Second)); err != nil {
+ t.Error(err)
+ }
+ if err := r.SetReadDeadline(noDeadline); err != nil {
+ t.Error(err)
+ }
+ var b [1]byte
+ _, err := r.Read(b[:])
+ ch <- err
+ }()
+
+ select {
+ case err := <-ch:
+ t.Fatalf("expected Read to not return, but it returned with %v", err)
+ case <-max.C:
+ w.Close()
+ err := <-ch // wait for tester goroutine to stop
+ if os.IsTimeout(err) {
+ t.Fatal(err)
+ }
+ }
+}
+
+var writeTimeoutTests = []struct {
+ timeout time.Duration
+ xerrs [2]error // expected errors in transition
+}{
+ // Tests that write deadlines work, even if there's buffer
+ // space available to write.
+ {-5 * time.Second, [2]error{poll.ErrTimeout, poll.ErrTimeout}},
+
+ {10 * time.Millisecond, [2]error{nil, poll.ErrTimeout}},
+}
+
+func TestWriteTimeout(t *testing.T) {
+ t.Parallel()
+
+ for i, tt := range writeTimeoutTests {
+ t.Run(fmt.Sprintf("#%d", i), func(t *testing.T) {
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ if err := w.SetWriteDeadline(time.Now().Add(tt.timeout)); err != nil {
+ t.Fatalf("%v", err)
+ }
+ for j, xerr := range tt.xerrs {
+ for {
+ n, err := w.Write([]byte("WRITE TIMEOUT TEST"))
+ if xerr != nil {
+ if !os.IsTimeout(err) {
+ t.Fatalf("%d: %v", j, err)
+ }
+ }
+ if err == nil {
+ time.Sleep(tt.timeout / 3)
+ continue
+ }
+ if n != 0 {
+ t.Fatalf("%d: wrote %d; want 0", j, n)
+ }
+ break
+ }
+ }
+ })
+ }
+}
+
+func TestWriteTimeoutMustNotReturn(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ max := time.NewTimer(100 * time.Millisecond)
+ defer max.Stop()
+ ch := make(chan error)
+ go func() {
+ if err := w.SetDeadline(time.Now().Add(-5 * time.Second)); err != nil {
+ t.Error(err)
+ }
+ if err := w.SetReadDeadline(time.Now().Add(-5 * time.Second)); err != nil {
+ t.Error(err)
+ }
+ if err := w.SetWriteDeadline(noDeadline); err != nil {
+ t.Error(err)
+ }
+ var b [1]byte
+ for {
+ if _, err := w.Write(b[:]); err != nil {
+ ch <- err
+ break
+ }
+ }
+ }()
+
+ select {
+ case err := <-ch:
+ t.Fatalf("expected Write to not return, but it returned with %v", err)
+ case <-max.C:
+ r.Close()
+ err := <-ch // wait for tester goroutine to stop
+ if os.IsTimeout(err) {
+ t.Fatal(err)
+ }
+ }
+}
+
+func timeoutReader(r *os.File, d, min, max time.Duration, ch chan<- error) {
+ var err error
+ defer func() { ch <- err }()
+
+ t0 := time.Now()
+ if err = r.SetReadDeadline(time.Now().Add(d)); err != nil {
+ return
+ }
+ b := make([]byte, 256)
+ var n int
+ n, err = r.Read(b)
+ t1 := time.Now()
+ if n != 0 || err == nil || !os.IsTimeout(err) {
+ err = fmt.Errorf("Read did not return (0, timeout): (%d, %v)", n, err)
+ return
+ }
+ if dt := t1.Sub(t0); min > dt || dt > max && !testing.Short() {
+ err = fmt.Errorf("Read took %s; expected %s", dt, d)
+ return
+ }
+}
+
+func TestReadTimeoutFluctuation(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ max := time.NewTimer(time.Second)
+ defer max.Stop()
+ ch := make(chan error)
+ go timeoutReader(r, 100*time.Millisecond, 50*time.Millisecond, 250*time.Millisecond, ch)
+
+ select {
+ case <-max.C:
+ t.Fatal("Read took over 1s; expected 0.1s")
+ case err := <-ch:
+ if !os.IsTimeout(err) {
+ t.Fatal(err)
+ }
+ }
+}
+
+func timeoutWriter(w *os.File, d, min, max time.Duration, ch chan<- error) {
+ var err error
+ defer func() { ch <- err }()
+
+ t0 := time.Now()
+ if err = w.SetWriteDeadline(time.Now().Add(d)); err != nil {
+ return
+ }
+ var n int
+ for {
+ n, err = w.Write([]byte("TIMEOUT WRITER"))
+ if err != nil {
+ break
+ }
+ }
+ t1 := time.Now()
+ if err == nil || !os.IsTimeout(err) {
+ err = fmt.Errorf("Write did not return (any, timeout): (%d, %v)", n, err)
+ return
+ }
+ if dt := t1.Sub(t0); min > dt || dt > max && !testing.Short() {
+ err = fmt.Errorf("Write took %s; expected %s", dt, d)
+ return
+ }
+}
+
+func TestWriteTimeoutFluctuation(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ d := time.Second
+ max := time.NewTimer(d)
+ defer max.Stop()
+ ch := make(chan error)
+ go timeoutWriter(w, 100*time.Millisecond, 50*time.Millisecond, 250*time.Millisecond, ch)
+
+ select {
+ case <-max.C:
+ t.Fatalf("Write took over %v; expected 0.1s", d)
+ case err := <-ch:
+ if !os.IsTimeout(err) {
+ t.Fatal(err)
+ }
+ }
+}
+
+func TestVariousDeadlines(t *testing.T) {
+ t.Parallel()
+ testVariousDeadlines(t)
+}
+
+func TestVariousDeadlines1Proc(t *testing.T) {
+ // Cannot use t.Parallel - modifies global GOMAXPROCS.
+ if testing.Short() {
+ t.Skip("skipping in short mode")
+ }
+ defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(1))
+ testVariousDeadlines(t)
+}
+
+func TestVariousDeadlines4Proc(t *testing.T) {
+ // Cannot use t.Parallel - modifies global GOMAXPROCS.
+ if testing.Short() {
+ t.Skip("skipping in short mode")
+ }
+ defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(4))
+ testVariousDeadlines(t)
+}
+
+type neverEnding byte
+
+func (b neverEnding) Read(p []byte) (int, error) {
+ for i := range p {
+ p[i] = byte(b)
+ }
+ return len(p), nil
+}
+
+func testVariousDeadlines(t *testing.T) {
+ type result struct {
+ n int64
+ err error
+ d time.Duration
+ }
+
+ handler := func(w *os.File, pasvch chan result) {
+ // The writer, with no timeouts of its own,
+ // sending bytes to clients as fast as it can.
+ t0 := time.Now()
+ n, err := io.Copy(w, neverEnding('a'))
+ dt := time.Since(t0)
+ pasvch <- result{n, err, dt}
+ }
+
+ for _, timeout := range []time.Duration{
+ 1 * time.Nanosecond,
+ 2 * time.Nanosecond,
+ 5 * time.Nanosecond,
+ 50 * time.Nanosecond,
+ 100 * time.Nanosecond,
+ 200 * time.Nanosecond,
+ 500 * time.Nanosecond,
+ 750 * time.Nanosecond,
+ 1 * time.Microsecond,
+ 5 * time.Microsecond,
+ 25 * time.Microsecond,
+ 250 * time.Microsecond,
+ 500 * time.Microsecond,
+ 1 * time.Millisecond,
+ 5 * time.Millisecond,
+ 100 * time.Millisecond,
+ 250 * time.Millisecond,
+ 500 * time.Millisecond,
+ 1 * time.Second,
+ } {
+ numRuns := 3
+ if testing.Short() {
+ numRuns = 1
+ if timeout > 500*time.Microsecond {
+ continue
+ }
+ }
+ for run := 0; run < numRuns; run++ {
+ t.Run(fmt.Sprintf("%v-%d", timeout, run+1), func(t *testing.T) {
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ pasvch := make(chan result)
+ go handler(w, pasvch)
+
+ tooLong := 5 * time.Second
+ max := time.NewTimer(tooLong)
+ defer max.Stop()
+ actvch := make(chan result)
+ go func() {
+ t0 := time.Now()
+ if err := r.SetDeadline(t0.Add(timeout)); err != nil {
+ t.Error(err)
+ }
+ n, err := io.Copy(ioutil.Discard, r)
+ dt := time.Since(t0)
+ r.Close()
+ actvch <- result{n, err, dt}
+ }()
+
+ select {
+ case res := <-actvch:
+ if os.IsTimeout(res.err) {
+ t.Logf("good client timeout after %v, reading %d bytes", res.d, res.n)
+ } else {
+ t.Fatalf("client Copy = %d, %v; want timeout", res.n, res.err)
+ }
+ case <-max.C:
+ t.Fatalf("timeout (%v) waiting for client to timeout (%v) reading", tooLong, timeout)
+ }
+
+ select {
+ case res := <-pasvch:
+ t.Logf("writer in %v wrote %d: %v", res.d, res.n, res.err)
+ case <-max.C:
+ t.Fatalf("timeout waiting for writer to finish writing")
+ }
+ })
+ }
+ }
+}
+
+func TestReadWriteDeadlineRace(t *testing.T) {
+ t.Parallel()
+
+ N := 1000
+ if testing.Short() {
+ N = 50
+ }
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ var wg sync.WaitGroup
+ wg.Add(3)
+ go func() {
+ defer wg.Done()
+ tic := time.NewTicker(2 * time.Microsecond)
+ defer tic.Stop()
+ for i := 0; i < N; i++ {
+ if err := r.SetReadDeadline(time.Now().Add(2 * time.Microsecond)); err != nil {
+ break
+ }
+ if err := w.SetWriteDeadline(time.Now().Add(2 * time.Microsecond)); err != nil {
+ break
+ }
+ <-tic.C
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ var b [1]byte
+ for i := 0; i < N; i++ {
+ _, err := r.Read(b[:])
+ if err != nil && !os.IsTimeout(err) {
+ t.Error("Read returned non-timeout error", err)
+ }
+ }
+ }()
+ go func() {
+ defer wg.Done()
+ var b [1]byte
+ for i := 0; i < N; i++ {
+ _, err := w.Write(b[:])
+ if err != nil && !os.IsTimeout(err) {
+ t.Error("Write returned non-timeout error", err)
+ }
+ }
+ }()
+ wg.Wait() // wait for tester goroutine to stop
+}
+
+// TestRacyRead tests that it is safe to mutate the input Read buffer
+// immediately after cancelation has occurred.
+func TestRacyRead(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ var wg sync.WaitGroup
+ defer wg.Wait()
+
+ go io.Copy(w, rand.New(rand.NewSource(0)))
+
+ r.SetReadDeadline(time.Now().Add(time.Millisecond))
+ for i := 0; i < 10; i++ {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+
+ b1 := make([]byte, 1024)
+ b2 := make([]byte, 1024)
+ for j := 0; j < 100; j++ {
+ _, err := r.Read(b1)
+ copy(b1, b2) // Mutate b1 to trigger potential race
+ if err != nil {
+ if !os.IsTimeout(err) {
+ t.Error(err)
+ }
+ r.SetReadDeadline(time.Now().Add(time.Millisecond))
+ }
+ }
+ }()
+ }
+}
+
+// TestRacyWrite tests that it is safe to mutate the input Write buffer
+// immediately after cancelation has occurred.
+func TestRacyWrite(t *testing.T) {
+ t.Parallel()
+
+ r, w, err := os.Pipe()
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer r.Close()
+ defer w.Close()
+
+ var wg sync.WaitGroup
+ defer wg.Wait()
+
+ go io.Copy(ioutil.Discard, r)
+
+ w.SetWriteDeadline(time.Now().Add(time.Millisecond))
+ for i := 0; i < 10; i++ {
+ wg.Add(1)
+ go func() {
+ defer wg.Done()
+
+ b1 := make([]byte, 1024)
+ b2 := make([]byte, 1024)
+ for j := 0; j < 100; j++ {
+ _, err := w.Write(b1)
+ copy(b1, b2) // Mutate b1 to trigger potential race
+ if err != nil {
+ if !os.IsTimeout(err) {
+ t.Error(err)
+ }
+ w.SetWriteDeadline(time.Now().Add(time.Millisecond))
+ }
+ }
+ }()
+ }
+}