src/runtime/crash_unix_test.go - go - Git at Google

 // Copyright 2012 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 darwin dragonfly freebsd linux netbsd openbsd solaris

 package runtime_test

 import (
 	"bytes"
 	"internal/testenv"
 	"io"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
 	"syscall"
 	"testing"
 )

 // sigquit is the signal to send to kill a hanging testdata program.
 // Send SIGQUIT to get a stack trace.
 var sigquit = syscall.SIGQUIT

 func init() {
 	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
 		// We can't use SIGQUIT to kill subprocesses because
 		// it's blocked. Use SIGKILL instead. See issue
 		// #19196 for an example of when this happens.
 		sigquit = syscall.SIGKILL
 	}
 }

 func TestCrashDumpsAllThreads(t *testing.T) {
 	switch runtime.GOOS {
 	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
 	default:
 		t.Skipf("skipping; not supported on %v", runtime.GOOS)
 	}

 	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
 		t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
 	}

 	// We don't use executeTest because we need to kill the
 	// program while it is running.

 	testenv.MustHaveGoBuild(t)

 	checkStaleRuntime(t)

 	t.Parallel()

 	dir, err := ioutil.TempDir("", "go-build")
 	if err != nil {
 		t.Fatalf("failed to create temp directory: %v", err)
 	}
 	defer os.RemoveAll(dir)

 	if err := ioutil.WriteFile(filepath.Join(dir, "main.go"), []byte(crashDumpsAllThreadsSource), 0666); err != nil {
 		t.Fatalf("failed to create Go file: %v", err)
 	}

 	cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", "a.exe")
 	cmd.Dir = dir
 	out, err := testEnv(cmd).CombinedOutput()
 	if err != nil {
 		t.Fatalf("building source: %v\n%s", err, out)
 	}

 	cmd = exec.Command(filepath.Join(dir, "a.exe"))
 	cmd = testEnv(cmd)
 	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")

 	// Set GOGC=off. Because of golang.org/issue/10958, the tight
 	// loops in the test program are not preemptible. If GC kicks
 	// in, it may lock up and prevent main from saying it's ready.
 	newEnv := []string{}
 	for _, s := range cmd.Env {
 		if !strings.HasPrefix(s, "GOGC=") {
 			newEnv = append(newEnv, s)
 		}
 	}
 	cmd.Env = append(newEnv, "GOGC=off")

 	var outbuf bytes.Buffer
 	cmd.Stdout = &outbuf
 	cmd.Stderr = &outbuf

 	rp, wp, err := os.Pipe()
 	if err != nil {
 		t.Fatal(err)
 	}
 	cmd.ExtraFiles = []*os.File{wp}

 	if err := cmd.Start(); err != nil {
 		t.Fatalf("starting program: %v", err)
 	}

 	if err := wp.Close(); err != nil {
 		t.Logf("closing write pipe: %v", err)
 	}
 	if _, err := rp.Read(make([]byte, 1)); err != nil {
 		t.Fatalf("reading from pipe: %v", err)
 	}

 	if err := cmd.Process.Signal(syscall.SIGQUIT); err != nil {
 		t.Fatalf("signal: %v", err)
 	}

 	// No point in checking the error return from Wait--we expect
 	// it to fail.
 	cmd.Wait()

 	// We want to see a stack trace for each thread.
 	// Before https://golang.org/cl/2811 running threads would say
 	// "goroutine running on other thread; stack unavailable".
 	out = outbuf.Bytes()
 	n := bytes.Count(out, []byte("main.loop("))
 	if n != 4 {
 		t.Errorf("found %d instances of main.loop; expected 4", n)
 		t.Logf("%s", out)
 	}
 }

 const crashDumpsAllThreadsSource = `
 package main

 import (
 	"fmt"
 	"os"
 	"runtime"
 )

 func main() {
 	const count = 4
 	runtime.GOMAXPROCS(count + 1)

 	chans := make([]chan bool, count)
 	for i := range chans {
 		chans[i] = make(chan bool)
 		go loop(i, chans[i])
 	}

 	// Wait for all the goroutines to start executing.
 	for _, c := range chans {
 		<-c
 	}

 	// Tell our parent that all the goroutines are executing.
 	if _, err := os.NewFile(3, "pipe").WriteString("x"); err != nil {
 		fmt.Fprintf(os.Stderr, "write to pipe failed: %v\n", err)
 		os.Exit(2)
 	}

 	select {}
 }

 func loop(i int, c chan bool) {
 	close(c)
 	for {
 		for j := 0; j < 0x7fffffff; j++ {
 		}
 	}
 }
 `

 func TestPanicSystemstack(t *testing.T) {
 	// Test that GOTRACEBACK=crash prints both the system and user
 	// stack of other threads.

 	// The GOTRACEBACK=crash handler takes 0.1 seconds even if
 	// it's not writing a core file and potentially much longer if
 	// it is. Skip in short mode.
 	if testing.Short() {
 		t.Skip("Skipping in short mode (GOTRACEBACK=crash is slow)")
 	}

 	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
 		t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
 	}

 	t.Parallel()
 	cmd := exec.Command(os.Args[0], "testPanicSystemstackInternal")
 	cmd = testEnv(cmd)
 	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
 	pr, pw, err := os.Pipe()
 	if err != nil {
 		t.Fatal("creating pipe: ", err)
 	}
 	cmd.Stderr = pw
 	if err := cmd.Start(); err != nil {
 		t.Fatal("starting command: ", err)
 	}
 	defer cmd.Process.Wait()
 	defer cmd.Process.Kill()
 	if err := pw.Close(); err != nil {
 		t.Log("closing write pipe: ", err)
 	}
 	defer pr.Close()

 	// Wait for "x\nx\n" to indicate readiness.
 	buf := make([]byte, 4)
 	_, err = io.ReadFull(pr, buf)
 	if err != nil || string(buf) != "x\nx\n" {
 		t.Fatal("subprocess failed; output:\n", string(buf))
 	}

 	// Send SIGQUIT.
 	if err := cmd.Process.Signal(syscall.SIGQUIT); err != nil {
 		t.Fatal("signaling subprocess: ", err)
 	}

 	// Get traceback.
 	tb, err := ioutil.ReadAll(pr)
 	if err != nil {
 		t.Fatal("reading traceback from pipe: ", err)
 	}

 	// Traceback should have two testPanicSystemstackInternal's
 	// and two blockOnSystemStackInternal's.
 	if bytes.Count(tb, []byte("testPanicSystemstackInternal")) != 2 {
 		t.Fatal("traceback missing user stack:\n", string(tb))
 	} else if bytes.Count(tb, []byte("blockOnSystemStackInternal")) != 2 {
 		t.Fatal("traceback missing system stack:\n", string(tb))
 	}
 }

 func init() {
 	if len(os.Args) >= 2 && os.Args[1] == "testPanicSystemstackInternal" {
 		// Get two threads running on the system stack with
 		// something recognizable in the stack trace.
 		runtime.GOMAXPROCS(2)
 		go testPanicSystemstackInternal()
 		testPanicSystemstackInternal()
 	}
 }

 func testPanicSystemstackInternal() {
 	runtime.BlockOnSystemStack()
 	os.Exit(1) // Should be unreachable.
 }

 func TestSignalExitStatus(t *testing.T) {
 	testenv.MustHaveGoBuild(t)
 	exe, err := buildTestProg(t, "testprog")
 	if err != nil {
 		t.Fatal(err)
 	}
 	err = testEnv(exec.Command(exe, "SignalExitStatus")).Run()
 	if err == nil {
 		t.Error("test program succeeded unexpectedly")
 	} else if ee, ok := err.(*exec.ExitError); !ok {
 		t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
 	} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
 		t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
 	} else if !ws.Signaled() || ws.Signal() != syscall.SIGTERM {
 		t.Errorf("got %v; expected SIGTERM", ee)
 	}
 }

 func TestSignalIgnoreSIGTRAP(t *testing.T) {
 	output := runTestProg(t, "testprognet", "SignalIgnoreSIGTRAP")
 	want := "OK\n"
 	if output != want {
 		t.Fatalf("want %s, got %s\n", want, output)
 	}
 }

 func TestSignalDuringExec(t *testing.T) {
 	switch runtime.GOOS {
 	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd":
 	default:
 		t.Skipf("skipping test on %s", runtime.GOOS)
 	}
 	output := runTestProg(t, "testprognet", "SignalDuringExec")
 	want := "OK\n"
 	if output != want {
 		t.Fatalf("want %s, got %s\n", want, output)
 	}
 }
	// Copyright 2012 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 darwin dragonfly freebsd linux netbsd openbsd solaris

	package runtime_test

	import (
	"bytes"
	"internal/testenv"
	"io"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"
	"syscall"
	"testing"
	)

	// sigquit is the signal to send to kill a hanging testdata program.
	// Send SIGQUIT to get a stack trace.
	var sigquit = syscall.SIGQUIT

	func init() {
	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
	// We can't use SIGQUIT to kill subprocesses because
	// it's blocked. Use SIGKILL instead. See issue
	// #19196 for an example of when this happens.
	sigquit = syscall.SIGKILL
	}
	}

	func TestCrashDumpsAllThreads(t *testing.T) {
	switch runtime.GOOS {
	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
	default:
	t.Skipf("skipping; not supported on %v", runtime.GOOS)
	}

	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
	t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
	}

	// We don't use executeTest because we need to kill the
	// program while it is running.

	testenv.MustHaveGoBuild(t)

	checkStaleRuntime(t)

	t.Parallel()

	dir, err := ioutil.TempDir("", "go-build")
	if err != nil {
	t.Fatalf("failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(dir)

	if err := ioutil.WriteFile(filepath.Join(dir, "main.go"), []byte(crashDumpsAllThreadsSource), 0666); err != nil {
	t.Fatalf("failed to create Go file: %v", err)
	}

	cmd := exec.Command(testenv.GoToolPath(t), "build", "-o", "a.exe")
	cmd.Dir = dir
	out, err := testEnv(cmd).CombinedOutput()
	if err != nil {
	t.Fatalf("building source: %v\n%s", err, out)
	}

	cmd = exec.Command(filepath.Join(dir, "a.exe"))
	cmd = testEnv(cmd)
	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")

	// Set GOGC=off. Because of golang.org/issue/10958, the tight
	// loops in the test program are not preemptible. If GC kicks
	// in, it may lock up and prevent main from saying it's ready.
	newEnv := []string{}
	for _, s := range cmd.Env {
	if !strings.HasPrefix(s, "GOGC=") {
	newEnv = append(newEnv, s)
	}
	}
	cmd.Env = append(newEnv, "GOGC=off")

	var outbuf bytes.Buffer
	cmd.Stdout = &outbuf
	cmd.Stderr = &outbuf

	rp, wp, err := os.Pipe()
	if err != nil {
	t.Fatal(err)
	}
	cmd.ExtraFiles = []*os.File{wp}

	if err := cmd.Start(); err != nil {
	t.Fatalf("starting program: %v", err)
	}

	if err := wp.Close(); err != nil {
	t.Logf("closing write pipe: %v", err)
	}
	if _, err := rp.Read(make([]byte, 1)); err != nil {
	t.Fatalf("reading from pipe: %v", err)
	}

	if err := cmd.Process.Signal(syscall.SIGQUIT); err != nil {
	t.Fatalf("signal: %v", err)
	}

	// No point in checking the error return from Wait--we expect
	// it to fail.
	cmd.Wait()

	// We want to see a stack trace for each thread.
	// Before https://golang.org/cl/2811 running threads would say
	// "goroutine running on other thread; stack unavailable".
	out = outbuf.Bytes()
	n := bytes.Count(out, []byte("main.loop("))
	if n != 4 {
	t.Errorf("found %d instances of main.loop; expected 4", n)
	t.Logf("%s", out)
	}
	}

	const crashDumpsAllThreadsSource = `
	package main

	import (
	"fmt"
	"os"
	"runtime"
	)

	func main() {
	const count = 4
	runtime.GOMAXPROCS(count + 1)

	chans := make([]chan bool, count)
	for i := range chans {
	chans[i] = make(chan bool)
	go loop(i, chans[i])
	}

	// Wait for all the goroutines to start executing.
	for _, c := range chans {
	<-c
	}

	// Tell our parent that all the goroutines are executing.
	if _, err := os.NewFile(3, "pipe").WriteString("x"); err != nil {
	fmt.Fprintf(os.Stderr, "write to pipe failed: %v\n", err)
	os.Exit(2)
	}

	select {}
	}

	func loop(i int, c chan bool) {
	close(c)
	for {
	for j := 0; j < 0x7fffffff; j++ {
	}
	}
	}
	`

	func TestPanicSystemstack(t *testing.T) {
	// Test that GOTRACEBACK=crash prints both the system and user
	// stack of other threads.

	// The GOTRACEBACK=crash handler takes 0.1 seconds even if
	// it's not writing a core file and potentially much longer if
	// it is. Skip in short mode.
	if testing.Short() {
	t.Skip("Skipping in short mode (GOTRACEBACK=crash is slow)")
	}

	if runtime.Sigisblocked(int(syscall.SIGQUIT)) {
	t.Skip("skipping; SIGQUIT is blocked, see golang.org/issue/19196")
	}

	t.Parallel()
	cmd := exec.Command(os.Args[0], "testPanicSystemstackInternal")
	cmd = testEnv(cmd)
	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
	pr, pw, err := os.Pipe()
	if err != nil {
	t.Fatal("creating pipe: ", err)
	}
	cmd.Stderr = pw
	if err := cmd.Start(); err != nil {
	t.Fatal("starting command: ", err)
	}
	defer cmd.Process.Wait()
	defer cmd.Process.Kill()
	if err := pw.Close(); err != nil {
	t.Log("closing write pipe: ", err)
	}
	defer pr.Close()

	// Wait for "x\nx\n" to indicate readiness.
	buf := make([]byte, 4)
	_, err = io.ReadFull(pr, buf)
	if err != nil \|\| string(buf) != "x\nx\n" {
	t.Fatal("subprocess failed; output:\n", string(buf))
	}

	// Send SIGQUIT.
	if err := cmd.Process.Signal(syscall.SIGQUIT); err != nil {
	t.Fatal("signaling subprocess: ", err)
	}

	// Get traceback.
	tb, err := ioutil.ReadAll(pr)
	if err != nil {
	t.Fatal("reading traceback from pipe: ", err)
	}

	// Traceback should have two testPanicSystemstackInternal's
	// and two blockOnSystemStackInternal's.
	if bytes.Count(tb, []byte("testPanicSystemstackInternal")) != 2 {
	t.Fatal("traceback missing user stack:\n", string(tb))
	} else if bytes.Count(tb, []byte("blockOnSystemStackInternal")) != 2 {
	t.Fatal("traceback missing system stack:\n", string(tb))
	}
	}

	func init() {
	if len(os.Args) >= 2 && os.Args[1] == "testPanicSystemstackInternal" {
	// Get two threads running on the system stack with
	// something recognizable in the stack trace.
	runtime.GOMAXPROCS(2)
	go testPanicSystemstackInternal()
	testPanicSystemstackInternal()
	}
	}

	func testPanicSystemstackInternal() {
	runtime.BlockOnSystemStack()
	os.Exit(1) // Should be unreachable.
	}

	func TestSignalExitStatus(t *testing.T) {
	testenv.MustHaveGoBuild(t)
	exe, err := buildTestProg(t, "testprog")
	if err != nil {
	t.Fatal(err)
	}
	err = testEnv(exec.Command(exe, "SignalExitStatus")).Run()
	if err == nil {
	t.Error("test program succeeded unexpectedly")
	} else if ee, ok := err.(*exec.ExitError); !ok {
	t.Errorf("error (%v) has type %T; expected exec.ExitError", err, err)
	} else if ws, ok := ee.Sys().(syscall.WaitStatus); !ok {
	t.Errorf("error.Sys (%v) has type %T; expected syscall.WaitStatus", ee.Sys(), ee.Sys())
	} else if !ws.Signaled() \|\| ws.Signal() != syscall.SIGTERM {
	t.Errorf("got %v; expected SIGTERM", ee)
	}
	}

	func TestSignalIgnoreSIGTRAP(t *testing.T) {
	output := runTestProg(t, "testprognet", "SignalIgnoreSIGTRAP")
	want := "OK\n"
	if output != want {
	t.Fatalf("want %s, got %s\n", want, output)
	}
	}

	func TestSignalDuringExec(t *testing.T) {
	switch runtime.GOOS {
	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd":
	default:
	t.Skipf("skipping test on %s", runtime.GOOS)
	}
	output := runTestProg(t, "testprognet", "SignalDuringExec")
	want := "OK\n"
	if output != want {
	t.Fatalf("want %s, got %s\n", want, output)
	}
	}