moby/filesystem.go
2013-01-18 16:13:39 -08:00

52 lines
1 KiB
Go

package docker
import (
"fmt"
"os"
"os/exec"
)
type Filesystem struct {
RootFS string
RWPath string
Layers []string
}
func (fs *Filesystem) createMountPoints() error {
if err := os.Mkdir(fs.RootFS, 0700); err != nil && !os.IsExist(err) {
return err
}
if err := os.Mkdir(fs.RWPath, 0700); err != nil && !os.IsExist(err) {
return err
}
return nil
}
func (fs *Filesystem) Mount() error {
if err := fs.createMountPoints(); err != nil {
return err
}
rwBranch := fmt.Sprintf("%v=rw", fs.RWPath)
roBranches := ""
for _, layer := range fs.Layers {
roBranches += fmt.Sprintf("%v=ro:", layer)
}
branches := fmt.Sprintf("br:%v:%v", rwBranch, roBranches)
cmd := exec.Command("mount", "-t", "aufs", "-o", branches, "none", fs.RootFS)
if err := cmd.Run(); err != nil {
return err
}
return nil
}
func (fs *Filesystem) Umount() error {
return exec.Command("umount", fs.RootFS).Run()
}
func newFilesystem(rootfs string, rwpath string, layers []string) *Filesystem {
return &Filesystem{
RootFS: rootfs,
RWPath: rwpath,
Layers: layers,
}
}