unionfs: test debug_setting symlink.

fuse/pathfs/api.go

@@ -18,6 +18,9 @@ type FileSystem interface {
 	// Used for pretty printing.
 	String() string
 
+	// If called, provide debug output through the log package.
+	SetDebug(debug bool)
+
 	// Attributes.  This function is the main entry point, through
 	// which FUSE discovers which files and directories exist.
 	//

fuse/pathfs/default.go

@@ -16,6 +16,8 @@ func NewDefaultFileSystem() FileSystem {
 // defaultFileSystem implements a FileSystem that returns ENOSYS for every operation.
 type defaultFileSystem struct{}
 
+func (fs *defaultFileSystem) SetDebug(debug bool) {}
+
 // defaultFileSystem
 func (fs *defaultFileSystem) GetAttr(name string, context *fuse.Context) (*fuse.Attr, fuse.Status) {
 	return nil, fuse.ENOSYS

fuse/pathfs/locking.go

@@ -28,6 +28,11 @@ func (fs *lockingFileSystem) String() string {
 	return fs.FS.String()
 }
 
+func (fs *lockingFileSystem) SetDebug(debug bool) {
+	defer fs.locked()()
+	fs.FS.SetDebug(debug)
+}
+
 func (fs *lockingFileSystem) StatFs(name string) *fuse.StatfsOut {
 	defer fs.locked()()
 	return fs.FS.StatFs(name)

fuse/pathfs/prefixfs.go

@@ -19,6 +19,10 @@ func NewPrefixFileSystem(fs FileSystem, prefix string) FileSystem {
 	return &prefixFileSystem{fs, prefix}
 }
 
+func (fs *prefixFileSystem) SetDebug(debug bool) {
+	fs.FileSystem.SetDebug(debug)
+}
+
 func (fs *prefixFileSystem) prefixed(n string) string {
 	return filepath.Join(fs.Prefix, n)
 }

unionfs/autounion.go

@@ -270,8 +270,7 @@ func (fs *autoUnionFs) Symlink(pointedTo string, linkName string, context *fuse.
 }
 
 func (fs *autoUnionFs) SetDebug(b bool) {
-	// Officially, this should use locking, but we don't care
-	// about race conditions here.
+	// TODO(hanwen): this should use locking.
 	fs.debug = b
 	fs.nodeFs.SetDebug(b)
 

unionfs/autounion_race_test.go

+// +build !race
+
+package unionfs
+
+import (
+	"os"
+	"testing"
+	"time"
+)
+
+// Ideally, this should check inject a logger rather than a boolean,
+// so we can check if the messages are as we expect.  Right now, this
+// test requires visual inspection. When run with -v, the UNLINK reply
+// and SYMLINK request are not printed.
+func TestToggleDebug(t *testing.T) {
+	wd, clean := setup(t)
+	defer clean()
+
+	os.Remove(wd + "/mnt/status/debug_setting")
+	time.Sleep(10 * time.Millisecond)
+
+	if err := os.Symlink("xyz", wd+"/mnt/status/debug_setting"); err != nil {
+		t.Fatalf("Symlink: %v", err)
+	}
+
+	// now we should be in debug mode.
+	link, err := os.Readlink(wd + "/mnt/status/debug_setting")
+	if err != nil {
+		t.Fatalf("Readlink: %v", err)
+	}
+	if link != "1" {
+		t.Errorf("got %q want %q for debug_setting readlink",
+			link, "1")
+	}
+}

unionfs/autounion_test.go

@@ -53,12 +53,11 @@ func setup(t *testing.T) (workdir string, cleanup func()) {
 	fs := NewAutoUnionFs(wd+"/store", testAOpts)
 
 	nfs := pathfs.NewPathNodeFs(fs, nil)
-	state, conn, err := nodefs.MountFileSystem(wd+"/mnt", nfs, &testAOpts.Options)
+	state, _, err := nodefs.MountFileSystem(wd+"/mnt", nfs, &testAOpts.Options)
 	if err != nil {
 		t.Fatalf("MountNodeFileSystem failed: %v", err)
 	}
-	state.SetDebug(VerboseTest())
-	conn.SetDebug(VerboseTest())
+	fs.SetDebug(VerboseTest())
 	go state.Serve()
 
 	return wd, func() {