github.com/mdempsky/go@v0.0.0-20151201204031-5dd372bd1e70/src/runtime/crash_unix_test.go (about)

     1  // Copyright 2012 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 darwin dragonfly freebsd linux netbsd openbsd solaris
     6  
     7  package runtime_test
     8  
     9  import (
    10  	"bytes"
    11  	"internal/testenv"
    12  	"io/ioutil"
    13  	"os"
    14  	"os/exec"
    15  	"path/filepath"
    16  	"runtime"
    17  	"syscall"
    18  	"testing"
    19  )
    20  
    21  func TestCrashDumpsAllThreads(t *testing.T) {
    22  	switch runtime.GOOS {
    23  	case "darwin", "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
    24  	default:
    25  		t.Skipf("skipping; not supported on %v", runtime.GOOS)
    26  	}
    27  
    28  	// We don't use executeTest because we need to kill the
    29  	// program while it is running.
    30  
    31  	testenv.MustHaveGoBuild(t)
    32  
    33  	checkStaleRuntime(t)
    34  
    35  	dir, err := ioutil.TempDir("", "go-build")
    36  	if err != nil {
    37  		t.Fatalf("failed to create temp directory: %v", err)
    38  	}
    39  	defer os.RemoveAll(dir)
    40  
    41  	if err := ioutil.WriteFile(filepath.Join(dir, "main.go"), []byte(crashDumpsAllThreadsSource), 0666); err != nil {
    42  		t.Fatalf("failed to create Go file: %v", err)
    43  	}
    44  
    45  	cmd := exec.Command("go", "build", "-o", "a.exe")
    46  	cmd.Dir = dir
    47  	out, err := testEnv(cmd).CombinedOutput()
    48  	if err != nil {
    49  		t.Fatalf("building source: %v\n%s", err, out)
    50  	}
    51  
    52  	cmd = exec.Command(filepath.Join(dir, "a.exe"))
    53  	cmd = testEnv(cmd)
    54  	cmd.Env = append(cmd.Env, "GOTRACEBACK=crash")
    55  	var outbuf bytes.Buffer
    56  	cmd.Stdout = &outbuf
    57  	cmd.Stderr = &outbuf
    58  
    59  	rp, wp, err := os.Pipe()
    60  	if err != nil {
    61  		t.Fatal(err)
    62  	}
    63  	cmd.ExtraFiles = []*os.File{wp}
    64  
    65  	if err := cmd.Start(); err != nil {
    66  		t.Fatalf("starting program: %v", err)
    67  	}
    68  
    69  	if err := wp.Close(); err != nil {
    70  		t.Logf("closing write pipe: %v", err)
    71  	}
    72  	if _, err := rp.Read(make([]byte, 1)); err != nil {
    73  		t.Fatalf("reading from pipe: %v", err)
    74  	}
    75  
    76  	if err := cmd.Process.Signal(syscall.SIGQUIT); err != nil {
    77  		t.Fatalf("signal: %v", err)
    78  	}
    79  
    80  	// No point in checking the error return from Wait--we expect
    81  	// it to fail.
    82  	cmd.Wait()
    83  
    84  	// We want to see a stack trace for each thread.
    85  	// Before https://golang.org/cl/2811 running threads would say
    86  	// "goroutine running on other thread; stack unavailable".
    87  	out = outbuf.Bytes()
    88  	n := bytes.Count(out, []byte("main.loop("))
    89  	if n != 4 {
    90  		t.Errorf("found %d instances of main.loop; expected 4", n)
    91  		t.Logf("%s", out)
    92  	}
    93  }
    94  
    95  const crashDumpsAllThreadsSource = `
    96  package main
    97  
    98  import (
    99  	"fmt"
   100  	"os"
   101  	"runtime"
   102  )
   103  
   104  func main() {
   105  	const count = 4
   106  	runtime.GOMAXPROCS(count + 1)
   107  
   108  	chans := make([]chan bool, count)
   109  	for i := range chans {
   110  		chans[i] = make(chan bool)
   111  		go loop(i, chans[i])
   112  	}
   113  
   114  	// Wait for all the goroutines to start executing.
   115  	for _, c := range chans {
   116  		<-c
   117  	}
   118  
   119  	// Tell our parent that all the goroutines are executing.
   120  	if _, err := os.NewFile(3, "pipe").WriteString("x"); err != nil {
   121  		fmt.Fprintf(os.Stderr, "write to pipe failed: %v\n", err)
   122  		os.Exit(2)
   123  	}
   124  
   125  	select {}
   126  }
   127  
   128  func loop(i int, c chan bool) {
   129  	close(c)
   130  	for {
   131  		for j := 0; j < 0x7fffffff; j++ {
   132  		}
   133  	}
   134  }
   135  `