vfs: factor Open logic from Dir.Create into vfs.OpenFile

cmd/cmount/fs.go

@@ -298,7 +298,11 @@ func (fsys *FS) Create(filePath string, flags int, mode uint32) (errc int, fh ui
 	if errc != 0 {
 		return errc, fhUnset
 	}
-	_, handle, err := parentDir.Create(leaf)
+	file, err := parentDir.Create(leaf)
+	if err != nil {
+		return translateError(err), fhUnset
+	}
+	handle, err := file.Open(flags)
 	if err != nil {
 		return translateError(err), fhUnset
 	}

cmd/mount/dir.go

@@ -122,7 +122,11 @@ var _ fusefs.NodeCreater = (*Dir)(nil)
 // Create makes a new file
 func (d *Dir) Create(ctx context.Context, req *fuse.CreateRequest, resp *fuse.CreateResponse) (node fusefs.Node, handle fusefs.Handle, err error) {
 	defer fs.Trace(d, "name=%q", req.Name)("node=%v, handle=%v, err=%v", &node, &handle, &err)
-	file, fh, err := d.Dir.Create(req.Name)
+	file, err := d.Dir.Create(req.Name)
+	if err != nil {
+		return nil, nil, translateError(err)
+	}
+	fh, err := file.Open(int(req.Flags))
 	if err != nil {
 		return nil, nil, translateError(err)
 	}

vfs/dir.go

@@ -316,23 +316,14 @@ func (d *Dir) Open(flags int) (fd Handle, err error) {
 	return newDirHandle(d), nil
 }
 
-// Create makes a new file
-func (d *Dir) Create(name string) (*File, *WriteFileHandle, error) {
-	if d.vfs.Opt.ReadOnly {
-		return nil, nil, EROFS
-	}
-	path := path.Join(d.path, name)
+// Create makes a new file node
+func (d *Dir) Create(name string) (*File, error) {
 	// fs.Debugf(path, "Dir.Create")
-	src := newCreateInfo(d.f, path)
-	// This gets added to the directory when the file is written
-	file := newFile(d, nil, name)
-	fh, err := newWriteFileHandle(d, file, src)
-	if err != nil {
-		fs.Errorf(d, "Dir.Create error: %v", err)
-		return nil, nil, err
+	if d.vfs.Opt.ReadOnly {
+		return nil, EROFS
 	}
-	// fs.Debugf(path, "Dir.Create OK")
-	return file, fh, nil
+	// This gets added to the directory when the file is written
+	return newFile(d, nil, name), nil
 }
 
 // Mkdir creates a new directory

vfs/dir_test.go

@@ -278,10 +278,13 @@ func TestDirCreate(t *testing.T) {
 	defer r.Finalise()
 	vfs, dir, _ := dirCreate(t, r)
 
-	file, fd, err := dir.Create("potato")
+	file, err := dir.Create("potato")
 	require.NoError(t, err)
 	assert.Equal(t, int64(0), file.Size())
 
+	fd, err := file.Open(os.O_WRONLY)
+	require.NoError(t, err)
+
 	// FIXME Note that this fails with the current implementation
 	// until the file has been opened.
 
@@ -300,7 +303,7 @@ func TestDirCreate(t *testing.T) {
 	assert.Equal(t, int64(5), file2.Size())
 
 	vfs.Opt.ReadOnly = true
-	_, _, err = dir.Create("sausage")
+	_, err = dir.Create("sausage")
 	assert.Equal(t, EROFS, err)
 }
 

vfs/file.go

@@ -33,12 +33,17 @@ func newFile(d *Dir, o fs.Object, leaf string) *File {
 	}
 }
 
+// path returns the full path of the file
+func (f *File) path() string {
+	return path.Join(f.d.path, f.leaf)
+}
+
 // String converts it to printable
 func (f *File) String() string {
 	if f == nil {
 		return "<nil *File>"
 	}
-	return path.Join(f.d.path, f.leaf)
+	return f.path()
 }
 
 // IsFile returns true for File - satisfies Node interface
@@ -228,14 +233,9 @@ func (f *File) OpenWrite() (fh *WriteFileHandle, err error) {
 	if f.d.vfs.Opt.ReadOnly {
 		return nil, EROFS
 	}
-	// if o is nil it isn't valid yet
-	o, err := f.waitForValidObject()
-	if err != nil {
-		return nil, err
-	}
 	// fs.Debugf(o, "File.OpenWrite")
 
-	src := newCreateInfo(f.d.f, o.Remote())
+	src := newCreateInfo(f.d.f, f.path())
 	fh, err = newWriteFileHandle(f.d, f, src)
 	err = errors.Wrap(err, "open for write")
 

vfs/vfs.go

@@ -266,15 +266,18 @@ func (vfs *VFS) StatParent(name string) (dir *Dir, leaf string, err error) {
 func (vfs *VFS) OpenFile(name string, flags int, perm os.FileMode) (fd Handle, err error) {
 	node, err := vfs.Stat(name)
 	if err != nil {
-		if err == ENOENT && flags&os.O_CREATE != 0 {
-			dir, leaf, err := vfs.StatParent(name)
-			if err != nil {
-				return nil, err
-			}
-			_, fd, err = dir.Create(leaf)
-			return fd, err
+		if err != ENOENT || flags&os.O_CREATE == 0 {
+			return nil, err
+		}
+		// If not found and O_CREATE then create the file
+		dir, leaf, err := vfs.StatParent(name)
+		if err != nil {
+			return nil, err
+		}
+		node, err = dir.Create(leaf)
+		if err != nil {
+			return nil, err
 		}
-		return nil, err
 	}
 	return node.Open(flags)
 }