1 files changed, 112 insertions, 5 deletions

diff --git a/libgo/go/os/signal/signal_test.go b/libgo/go/os/signal/signal_test.go
index 509b273..d138333 100644
--- a/libgo/go/os/signal/signal_test.go
+++ b/libgo/go/os/signal/signal_test.go
@@ -7,15 +7,17 @@
 package signal
 
 import (
+	"flag"
+	"io/ioutil"
 	"os"
+	"os/exec"
 	"runtime"
+	"strconv"
 	"syscall"
 	"testing"
 	"time"
 )
 
-const sighup = syscall.SIGHUP
-
 func waitSig(t *testing.T, c <-chan os.Signal, sig os.Signal) {
 	select {
 	case s := <-c:
@@ -27,15 +29,17 @@ func waitSig(t *testing.T, c <-chan os.Signal, sig os.Signal) {
 	}
 }
 
+// Test that basic signal handling works.
 func TestSignal(t *testing.T) {
 	// Ask for SIGHUP
 	c := make(chan os.Signal, 1)
-	Notify(c, sighup)
+	Notify(c, syscall.SIGHUP)
+	defer Stop(c)
 
 	t.Logf("sighup...")
 	// Send this process a SIGHUP
-	syscall.Kill(syscall.Getpid(), sighup)
-	waitSig(t, c, sighup)
+	syscall.Kill(syscall.Getpid(), syscall.SIGHUP)
+	waitSig(t, c, syscall.SIGHUP)
 
 	// Ask for everything we can get.
 	c1 := make(chan os.Signal, 1)
@@ -71,6 +75,7 @@ func TestStress(t *testing.T) {
 	go func() {
 		sig := make(chan os.Signal, 1)
 		Notify(sig, syscall.SIGUSR1)
+		defer Stop(sig)
 	Loop:
 		for {
 			select {
@@ -98,4 +103,106 @@ func TestStress(t *testing.T) {
 	close(done)
 	<-finished
 	<-finished
+	// When run with 'go test -cpu=1,2,4' SIGUSR1 from this test can slip
+	// into subsequent TestSignal() causing failure.
+	// Sleep for a while to reduce the possibility of the failure.
+	time.Sleep(10 * time.Millisecond)
+}
+
+var sendUncaughtSighup = flag.Int("send_uncaught_sighup", 0, "send uncaught SIGHUP during TestStop")
+
+// Test that Stop cancels the channel's registrations.
+func TestStop(t *testing.T) {
+	sigs := []syscall.Signal{
+		syscall.SIGWINCH,
+		syscall.SIGHUP,
+	}
+
+	for _, sig := range sigs {
+		// Send the signal.
+		// If it's SIGWINCH, we should not see it.
+		// If it's SIGHUP, maybe we'll die. Let the flag tell us what to do.
+		if sig != syscall.SIGHUP || *sendUncaughtSighup == 1 {
+			syscall.Kill(syscall.Getpid(), sig)
+		}
+		time.Sleep(10 * time.Millisecond)
+
+		// Ask for signal
+		c := make(chan os.Signal, 1)
+		Notify(c, sig)
+		defer Stop(c)
+
+		// Send this process that signal
+		syscall.Kill(syscall.Getpid(), sig)
+		waitSig(t, c, sig)
+
+		Stop(c)
+		select {
+		case s := <-c:
+			t.Fatalf("unexpected signal %v", s)
+		case <-time.After(10 * time.Millisecond):
+			// nothing to read - good
+		}
+
+		// Send the signal.
+		// If it's SIGWINCH, we should not see it.
+		// If it's SIGHUP, maybe we'll die. Let the flag tell us what to do.
+		if sig != syscall.SIGHUP || *sendUncaughtSighup == 2 {
+			syscall.Kill(syscall.Getpid(), sig)
+		}
+
+		select {
+		case s := <-c:
+			t.Fatalf("unexpected signal %v", s)
+		case <-time.After(10 * time.Millisecond):
+			// nothing to read - good
+		}
+	}
+}
+
+// Test that when run under nohup, an uncaught SIGHUP does not kill the program,
+// but a
+func TestNohup(t *testing.T) {
+	// Ugly: ask for SIGHUP so that child will not have no-hup set
+	// even if test is running under nohup environment.
+	// We have no intention of reading from c.
+	c := make(chan os.Signal, 1)
+	Notify(c, syscall.SIGHUP)
+
+	// When run without nohup, the test should crash on an uncaught SIGHUP.
+	// When run under nohup, the test should ignore uncaught SIGHUPs,
+	// because the runtime is not supposed to be listening for them.
+	// Either way, TestStop should still be able to catch them when it wants them
+	// and then when it stops wanting them, the original behavior should resume.
+	//
+	// send_uncaught_sighup=1 sends the SIGHUP before starting to listen for SIGHUPs.
+	// send_uncaught_sighup=2 sends the SIGHUP after no longer listening for SIGHUPs.
+	//
+	// Both should fail without nohup and succeed with nohup.
+
+	for i := 1; i <= 2; i++ {
+		out, err := exec.Command(os.Args[0], "-test.run=TestStop", "-send_uncaught_sighup="+strconv.Itoa(i)).CombinedOutput()
+		if err == nil {
+			t.Fatalf("ran test with -send_uncaught_sighup=%d and it succeeded: expected failure.\nOutput:\n%s", i, out)
+		}
+	}
+
+	Stop(c)
+
+	// Again, this time with nohup, assuming we can find it.
+	_, err := os.Stat("/usr/bin/nohup")
+	if err != nil {
+		t.Skip("cannot find nohup; skipping second half of test")
+	}
+
+	for i := 1; i <= 2; i++ {
+		os.Remove("nohup.out")
+		out, err := exec.Command("/usr/bin/nohup", os.Args[0], "-test.run=TestStop", "-send_uncaught_sighup="+strconv.Itoa(i)).CombinedOutput()
+
+		data, _ := ioutil.ReadFile("nohup.out")
+		os.Remove("nohup.out")
+		if err != nil {
+			t.Fatalf("ran test with -send_uncaught_sighup=%d under nohup and it failed: expected success.\nError: %v\nOutput:\n%s%s", i, err, out, data)
+		}
+	}
 }