tests: sharedstorage: add TestStaleHardlinks

tests/sharedstorage/sharedstorage_test.go

@@ -2,7 +2,10 @@
 package sharedstorage
 
 import (
+	"fmt"
+	"os"
 	"testing"
+	"time"
 
 	"golang.org/x/sys/unix"
 
@@ -11,11 +14,43 @@ import (
 
 var flagSharestorage bool
 
+const cacheTime = time.Second
+
 func TestMain(m *testing.M) {
+	ret := 0
 	flagSharestorage = false
-	m.Run()
+	ret += m.Run()
 	flagSharestorage = true
-	m.Run()
+	ret += m.Run()
+	os.Exit(ret)
+}
+
+type testCase struct {
+	t *testing.T
+
+	cipherdir string
+	mnt1      string
+	mnt2      string
+}
+
+func newTestCase(t *testing.T) *testCase {
+	tc := testCase{}
+	tc.cipherdir = test_helpers.InitFS(t)
+	tc.mnt1 = tc.cipherdir + ".mnt1"
+	tc.mnt2 = tc.cipherdir + ".mnt2"
+	mountSharedstorage(t, tc.cipherdir, tc.mnt1)
+	mountSharedstorage(t, tc.cipherdir, tc.mnt2)
+	t.Logf("newTestCase: sharedstorage=%v cipherdir=%q", flagSharestorage, tc.cipherdir)
+	return &tc
+}
+
+func (tc *testCase) cleanup() {
+	for _, mnt := range []string{tc.mnt1, tc.mnt2} {
+		err := test_helpers.UnmountErr(mnt)
+		if err != nil {
+			tc.t.Error(err)
+		}
+	}
 }
 
 // mountSharedstorage mounts `cipherdir` on `mnt` with or without the
@@ -28,34 +63,78 @@ func mountSharedstorage(t *testing.T, cipherdir string, mnt string) {
 	test_helpers.MountOrFatal(t, cipherdir, mnt, args...)
 }
 
-func TestUnlink(t *testing.T) {
-	cipherdir := test_helpers.InitFS(t)
-	mnt1 := cipherdir + ".mnt1"
-	mnt2 := cipherdir + ".mnt2"
-	mountSharedstorage(t, cipherdir, mnt1)
-	defer test_helpers.UnmountPanic(mnt1)
-	mountSharedstorage(t, cipherdir, mnt2)
-	defer test_helpers.UnmountPanic(mnt2)
+func TestDirUnlink(t *testing.T) {
+	tc := newTestCase(t)
+	defer tc.cleanup()
 
 	// Create dir via mnt1
-	if err := unix.Mkdir(mnt1+"/foo", 0700); err != nil {
+	if err := unix.Mkdir(tc.mnt1+"/foo", 0700); err != nil {
 		t.Fatal(err)
 	}
 	// Replace dir with file via mnt2
-	if err := unix.Rmdir(mnt2 + "/foo"); err != nil {
+	if err := unix.Rmdir(tc.mnt2 + "/foo"); err != nil {
 		t.Fatal(err)
 	}
-	if fd, err := unix.Creat(mnt2+"/foo", 0600); err != nil {
+	if fd, err := unix.Creat(tc.mnt2+"/foo", 0600); err != nil {
 		t.Fatal(err)
 	} else {
 		unix.Close(fd)
 	}
 	// Try to unlink via mnt1
-	if err := unix.Unlink(mnt1 + "/foo"); err != nil {
+	if err := unix.Unlink(tc.mnt1 + "/foo"); err != nil {
+		// Must work with -sharedstorage
 		if flagSharestorage {
 			t.Fatal(err)
 		} else {
-			t.Logf("Unlink failed as expected: errno %d / %v", err, err)
+			// Must always work after cache timeout
+			time.Sleep(cacheTime)
+			if err := unix.Unlink(tc.mnt1 + "/foo"); err != nil {
+				t.Fatal(err)
 			}
 		}
 	}
+}
+
+// TestStaleHardlinks always failed before
+// https://review.gerrithub.io/c/hanwen/go-fuse/+/513646/2
+func TestStaleHardlinks(t *testing.T) {
+	tc := newTestCase(t)
+	defer tc.cleanup()
+
+	link0 := tc.mnt1 + "/link0"
+	if fd, err := unix.Creat(link0, 0600); err != nil {
+		t.Fatal(err)
+	} else {
+		unix.Close(fd)
+	}
+	// Create hardlinks via mnt1
+	for i := 1; i < 20; i++ {
+		linki := fmt.Sprintf(tc.mnt1+"/link%d", i)
+		if err := unix.Link(link0, linki); err != nil {
+			t.Fatal(err)
+		}
+	}
+	// Delete hardlinks via mnt2
+	for i := 1; i < 20; i++ {
+		linki := fmt.Sprintf(tc.mnt2+"/link%d", i)
+		if err := unix.Unlink(linki); err != nil {
+			t.Fatal(err)
+		}
+	}
+	// Open link0 via mnt1
+	fd, err := unix.Open(link0, unix.O_RDONLY, 0)
+	if err != nil {
+		// Must work with -sharedstorage
+		if flagSharestorage {
+			t.Fatal(err)
+		} else {
+			// Must always work after cache timeout
+			time.Sleep(cacheTime)
+			fd, err = unix.Open(link0, unix.O_RDONLY, 0)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+	unix.Close(fd)
+}