containerd/vendor/github.com/moby/sys/mountinfo/mounted_unix.go
Hajime Tazaki b8f3ebb03b vendor: update moby/sys for darwin support
The mount package of darwin requires to retrive mountinfo to check if
the target of unmount if still mounted or not.  Thus pull the upstreamed
version of moby/sys to support this operation.

Signed-off-by: Hajime Tazaki <thehajime@gmail.com>
2021-10-23 07:48:17 +09:00

67 lines
1.6 KiB
Go

// +build linux freebsd,cgo openbsd,cgo darwin,cgo
package mountinfo
import (
"errors"
"fmt"
"os"
"path/filepath"
"golang.org/x/sys/unix"
)
func mountedByStat(path string) (bool, error) {
var st unix.Stat_t
if err := unix.Lstat(path, &st); err != nil {
if err == unix.ENOENT {
// Treat ENOENT as "not mounted".
return false, nil
}
return false, &os.PathError{Op: "stat", Path: path, Err: err}
}
dev := st.Dev
parent := filepath.Dir(path)
if err := unix.Lstat(parent, &st); err != nil {
return false, &os.PathError{Op: "stat", Path: parent, Err: err}
}
if dev != st.Dev {
// Device differs from that of parent,
// so definitely a mount point.
return true, nil
}
// NB: this does not detect bind mounts on Linux.
return false, nil
}
func normalizePath(path string) (realPath string, err error) {
if realPath, err = filepath.Abs(path); err != nil {
return "", fmt.Errorf("unable to get absolute path for %q: %w", path, err)
}
if realPath, err = filepath.EvalSymlinks(realPath); err != nil {
return "", fmt.Errorf("failed to canonicalise path for %q: %w", path, err)
}
if _, err := os.Stat(realPath); err != nil {
return "", fmt.Errorf("failed to stat target of %q: %w", path, err)
}
return realPath, nil
}
func mountedByMountinfo(path string) (bool, error) {
path, err := normalizePath(path)
if err != nil {
if errors.Is(err, unix.ENOENT) {
// treat ENOENT as "not mounted"
return false, nil
}
return false, err
}
entries, err := GetMounts(SingleEntryFilter(path))
if err != nil {
return false, err
}
return len(entries) > 0, nil
}