docker/graphdriver/vfs/driver.go

96 строки
1.8 KiB
Go

package vfs
import (
"fmt"
"github.com/dotcloud/docker/graphdriver"
"os"
"os/exec"
"path"
)
func init() {
graphdriver.Register("vfs", Init)
}
func Init(home string) (graphdriver.Driver, error) {
d := &Driver{
home: home,
}
return d, nil
}
type Driver struct {
home string
}
func (d *Driver) String() string {
return "vfs"
}
func (d *Driver) Status() [][2]string {
return nil
}
func (d *Driver) Cleanup() error {
return nil
}
func copyDir(src, dst string) error {
if output, err := exec.Command("cp", "-aT", "--reflink=auto", src, dst).CombinedOutput(); err != nil {
return fmt.Errorf("Error VFS copying directory: %s (%s)", err, output)
}
return nil
}
func (d *Driver) Create(id string, parent string) error {
dir := d.dir(id)
if err := os.MkdirAll(path.Dir(dir), 0700); err != nil {
return err
}
if err := os.Mkdir(dir, 0700); err != nil {
return err
}
if parent == "" {
return nil
}
parentDir, err := d.Get(parent)
if err != nil {
return fmt.Errorf("%s: %s", parent, err)
}
if err := copyDir(parentDir, dir); err != nil {
return err
}
return nil
}
func (d *Driver) dir(id string) string {
return path.Join(d.home, "dir", path.Base(id))
}
func (d *Driver) Remove(id string) error {
if _, err := os.Stat(d.dir(id)); err != nil {
return err
}
return os.RemoveAll(d.dir(id))
}
func (d *Driver) Get(id string) (string, error) {
dir := d.dir(id)
if st, err := os.Stat(dir); err != nil {
return "", err
} else if !st.IsDir() {
return "", fmt.Errorf("%s: not a directory", dir)
}
return dir, nil
}
func (d *Driver) Put(id string) {
// The vfs driver has no runtime resources (e.g. mounts)
// to clean up, so we don't need anything here
}
func (d *Driver) Exists(id string) bool {
_, err := os.Stat(d.dir(id))
return err == nil
}