fs: rename Options.DefaultPermissions to NullPermissions

This makes the default setting more useful.

Change-Id: Iab40ad0ab0e2c9b75b786a883f6ad989178ee5b5

example/multizip/main.go

@@ -32,9 +32,8 @@ func main() {
 	root := &zipfs.MultiZipFs{}
 	sec := time.Second
 	opts := fs.Options{
-		EntryTimeout:       &sec,
-		AttrTimeout:        &sec,
-		DefaultPermissions: true,
+		EntryTimeout: &sec,
+		AttrTimeout:  &sec,
 	}
 	opts.Debug = *debug
 	server, err := fs.Mount(flag.Arg(0), root, &opts)

example/zipfs/main.go

@@ -57,9 +57,8 @@ func main() {
 	}
 
 	opts := &fs.Options{
-		AttrTimeout:        ttl,
-		EntryTimeout:       ttl,
-		DefaultPermissions: true,
+		AttrTimeout:  ttl,
+		EntryTimeout: ttl,
 	}
 	opts.Debug = *debug
 	server, err := fs.Mount(flag.Arg(0), root, opts)

fs/api.go

@@ -217,9 +217,12 @@ type NodeAccesser interface {
 	Access(ctx context.Context, mask uint32) syscall.Errno
 }
 
-// GetAttr reads attributes for an Inode. The library will
-// ensure that Mode and Ino are set correctly. For regular
-// files, Size should be set so it can be read correctly.
+// GetAttr reads attributes for an Inode. The library will ensure that
+// Mode and Ino are set correctly. For files that are not opened with
+// FOPEN_DIRECTIO, Size should be set so it can be read correctly.  If
+// returning zeroed permissions, the default behavior is to change the
+// mode of 0755 (directory) or 0644 (files). This can be switched off
+// with the Options.NullPermissions setting.
 type NodeGetattrer interface {
 	Getattr(ctx context.Context, f FileHandle, out *fuse.AttrOut) syscall.Errno
 }
@@ -584,9 +587,11 @@ type Options struct {
 	// functionality of the root node.
 	OnAdd func(ctx context.Context)
 
-	// DefaultPermissions sets null file permissions to 755 (dirs)
-	// or 644 (other files.)
-	DefaultPermissions bool
+	// NullPermissions if set, leaves null file permissions
+	// alone. Otherwise, they are set to 755 (dirs) or 644 (other
+	// files.), which is necessary for doing a chdir into the FUSE
+	// directories.
+	NullPermissions bool
 
 	// If nonzero, replace default (zero) UID with the given UID
 	UID uint32

fs/bridge.go

@@ -147,7 +147,7 @@ func (b *rawBridge) setEntryOutTimeout(out *fuse.EntryOut) {
 }
 
 func (b *rawBridge) setAttr(out *fuse.Attr) {
-	if b.options.DefaultPermissions && out.Mode&07777 == 0 {
+	if !b.options.NullPermissions && out.Mode&07777 == 0 {
 		out.Mode |= 0644
 		if out.Mode&syscall.S_IFDIR != 0 {
 			out.Mode |= 0111

fs/dynamic_example_test.go

@@ -117,11 +117,6 @@ func Example_dynamic() {
 			// Set to true to see how the file system works.
 			Debug: true,
 		},
-
-		// This adds read permissions to the files and
-		// directories, which is necessary for doing a chdir
-		// into the mount.
-		DefaultPermissions: true,
 	})
 	if err != nil {
 		log.Panic(err)

fs/inmemory_example_test.go

@@ -80,11 +80,6 @@ func Example() {
 	root := &inMemoryFS{}
 	server, err := fs.Mount(mntDir, root, &fs.Options{
 		MountOptions: fuse.MountOptions{Debug: true},
-
-		// This adds read permissions to the files and
-		// directories, which is necessary for doing a chdir
-		// into the mount.
-		DefaultPermissions: true,
 	})
 	if err != nil {
 		log.Panic(err)

fs/readonly_test.go

@@ -29,7 +29,6 @@ func TestDefaultPermissions(t *testing.T) {
 	root := &Inode{}
 
 	mntDir, _, clean := testMount(t, root, &Options{
-		DefaultPermissions: true,
 		OnAdd: func(ctx context.Context) {
 			dir := root.NewPersistentInode(ctx, &Inode{}, StableAttr{Mode: syscall.S_IFDIR})
 			file := root.NewPersistentInode(ctx, &Inode{}, StableAttr{Mode: syscall.S_IFREG})