runc/libcontainer/mount_linux.go

84 lines
1.6 KiB
Go

package libcontainer
import (
"strconv"
"golang.org/x/sys/unix"
)
// mountError holds an error from a failed mount or unmount operation.
type mountError struct {
op string
source string
target string
procfd string
flags uintptr
data string
err error
}
// Error provides a string error representation.
func (e *mountError) Error() string {
out := e.op + " "
if e.source != "" {
out += e.source + ":" + e.target
} else {
out += e.target
}
if e.procfd != "" {
out += " (via " + e.procfd + ")"
}
if e.flags != uintptr(0) {
out += ", flags: 0x" + strconv.FormatUint(uint64(e.flags), 16)
}
if e.data != "" {
out += ", data: " + e.data
}
out += ": " + e.err.Error()
return out
}
// Unwrap returns the underlying error.
// This is a convention used by Go 1.13+ standard library.
func (e *mountError) Unwrap() error {
return e.err
}
// mount is a simple unix.Mount wrapper. If procfd is not empty, it is used
// instead of target (and the target is only used to add context to an error).
func mount(source, target, procfd, fstype string, flags uintptr, data string) error {
dst := target
if procfd != "" {
dst = procfd
}
if err := unix.Mount(source, dst, fstype, flags, data); err != nil {
return &mountError{
op: "mount",
source: source,
target: target,
procfd: procfd,
flags: flags,
data: data,
err: err,
}
}
return nil
}
// unmount is a simple unix.Unmount wrapper.
func unmount(target string, flags int) error {
err := unix.Unmount(target, flags)
if err != nil {
return &mountError{
op: "unmount",
target: target,
flags: uintptr(flags),
err: err,
}
}
return nil
}