src/syscall/zx/fdio/object.go

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build fuchsia

package fdio

import (
	"syscall/zx"
	"syscall/zx/fidl"
	"syscall/zx/io"
)

func objectFromInfo(info *io.ObjectInfo, obj *io.ObjectInterface) (result FDIO, err error) {
	if info == nil {
		return nil, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
	}
	switch info.ObjectInfoTag {
	case io.ObjectInfoService:
		// TODO(mknyszek): Figure out the correct type to return here.
		result = &Object{ObjectInterface: obj}
	case io.ObjectInfoFile:
		result = &File{
			Node:  Node{Object: Object{ObjectInterface: obj}},
			Event: info.File.Event,
		}
	case io.ObjectInfoDevice:
		result = &File{
			Node:  Node{Object: Object{ObjectInterface: obj}},
			Event: info.Device.Event,
		}
	case io.ObjectInfoDirectory:
		result = &Directory{Node: Node{Object: Object{ObjectInterface: obj}}}
	case io.ObjectInfoPipe:
		result = NewPipe(info.Pipe.Socket)
	case io.ObjectInfoVmofile:
		result, err = NewVMOFile(
			info.Vmofile.Vmo,
			info.Vmofile.Offset,
			info.Vmofile.Length,
		)
		if err != nil {
			return nil, err
		}
	default:
		return nil, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
	}
	return result, nil
}

// Object is a wrapper around an ObjectInterface which implements FDIO.
type Object struct {
	*io.ObjectInterface
}

// IsValid returns true if the Object is valid.
func (o *Object) IsValid() bool {
	if o.ObjectInterface == nil {
		return false
	}
	return ((*fidl.Proxy)(o.ObjectInterface)).IsValid()
}

// Handle returns the underlying channel as an untyped zx handle.
func (o *Object) Handles() []zx.Handle {
	return []zx.Handle{
		zx.Handle(((*fidl.Proxy)(o.ObjectInterface)).Channel),
	}
}

// Clone makes a clone of the object.
func (o *Object) Clone() (FDIO, error) {
	req, newObj, err := io.NewObjectInterfaceRequest()
	if err != nil {
		return nil, err
	}
	if err := o.ObjectInterface.Clone(io.KOpenFlagDescribe, req); err != nil {
		return nil, err
	}
	status, info, err := newObj.ExpectOnOpen()
	if err != nil {
		return nil, err
	} else if status != zx.ErrOk {
		return nil, zx.Error{Status: status, Text: "io.object"}
	}
	return objectFromInfo(info, newObj)
}

// Close closes the object.
func (o *Object) Close() error {
	defer ((*fidl.Proxy)(o.ObjectInterface)).Close()
	if status, err := o.ObjectInterface.Close(); err != nil {
		return err
	} else if status != zx.ErrOk {
		return zx.Error{Status: status, Text: "io.object"}
	}
	return nil
}

// Sync implements FDIO for Object.
func (o *Object) Sync() error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// GetAttr implements FDIO for Object.
func (o *Object) GetAttr() (io.NodeAttributes, error) {
	return io.NodeAttributes{}, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// SetAttr implements FDIO for Object.
func (o *Object) SetAttr(flags uint32, attr io.NodeAttributes) error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Ioctl implements FDIO for Object.
func (o *Object) Ioctl(op uint32, max uint64, in []byte, handles []zx.Handle) ([]byte, []zx.Handle, error) {
	return nil, nil, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Read implements FDIO for Object.
func (o *Object) Read(data []byte) (int, error) {
	return 0, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// ReadAt implements FDIO for Object.
func (o *Object) ReadAt(data []byte, off int64) (int, error) {
	return 0, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Write implements FDIO for Object.
func (o *Object) Write(data []byte) (int, error) {
	return 0, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// WriteAt implements FDIO for Object.
func (o *Object) WriteAt(data []byte, off int64) (int, error) {
	return 0, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Seek implements FDIO for Object.
func (o *Object) Seek(offset int64, whence int) (int64, error) {
	return 0, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Truncate implements FDIO for Object.
func (o *Object) Truncate(length uint64) error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Open implements FDIO for Object.
func (o *Object) Open(path string, flags uint32, mode uint32) (FDIO, error) {
	return nil, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Link implements FDIO for Object.
func (o *Object) Link(oldpath, newpath string) error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Rename implements FDIO for Object.
func (o *Object) Rename(oldpath, newpath string) error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Unlink implements FDIO for Object.
func (o *Object) Unlink(path string) error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// ReadDirents implements FDIO for Object.
func (o *Object) ReadDirents(max uint64) ([]byte, error) {
	return nil, zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}

// Rewind implements FDIO for Object.
func (o *Object) Rewind() error {
	return zx.Error{Status: zx.ErrNotSupported, Text: "io.object"}
}