func removeMountUnit(baseDir string, meter progress.Meter) error {
sysd := systemd.New(dirs.GlobalRootDir, meter)
unit := systemd.MountUnitPath(dirs.StripRootDir(baseDir), "mount")
if osutil.FileExists(unit) {
// use umount -l (lazy) to ensure that even busy mount points
// can be unmounted.
// note that the long option --lazy is not supported on trusty.
if output, err := exec.Command("umount", "-l", baseDir).CombinedOutput(); err != nil {
return osutil.OutputErr(output, err)
}
if err := sysd.Stop(filepath.Base(unit), time.Duration(1*time.Second)); err != nil {
return err
}
if err := sysd.Disable(filepath.Base(unit)); err != nil {
return err
}
if err := os.Remove(unit); err != nil {
return err
}
// daemon-reload to ensure that systemd actually really
// forgets about this mount unit
if err := sysd.DaemonReload(); err != nil {
return err
}
}
return nil
}
func addMountUnit(s *snap.Info, meter progress.Meter) error {
squashfsPath := dirs.StripRootDir(s.MountFile())
whereDir := dirs.StripRootDir(s.MountDir())
sysd := systemd.New(dirs.GlobalRootDir, meter)
mountUnitName, err := sysd.WriteMountUnitFile(s.Name(), squashfsPath, whereDir, "squashfs")
if err != nil {
return err
}
// we need to do a daemon-reload here to ensure that systemd really
// knows about this new mount unit file
if err := sysd.DaemonReload(); err != nil {
return err
}
if err := sysd.Enable(mountUnitName); err != nil {
return err
}
return sysd.Start(mountUnitName)
}