mount.go

/*
   Copyright The containerd Authors.

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package api

import (
	"sort"

	rspec "github.com/opencontainers/runtime-spec/specs-go"
)

const (
	// SELinuxRelabel is a Mount pseudo-option to request relabeling.
	SELinuxRelabel = "relabel"
)

// FromOCIMounts returns a Mount slice for an OCI runtime Spec.
func FromOCIMounts(o []rspec.Mount) []*Mount {
	var mounts []*Mount
	for _, m := range o {
		mounts = append(mounts, &Mount{
			Destination: m.Destination,
			Type:        m.Type,
			Source:      m.Source,
			Options:     DupStringSlice(m.Options),
		})
	}
	return mounts
}

// ToOCI returns a Mount for an OCI runtime Spec.
func (m *Mount) ToOCI(propagationQuery *string) rspec.Mount {
	o := rspec.Mount{
		Destination: m.Destination,
		Type:        m.Type,
		Source:      m.Source,
	}
	for _, opt := range m.Options {
		o.Options = append(o.Options, opt)
		if propagationQuery != nil && (opt == "rprivate" || opt == "rshared" || opt == "rslave") {
			*propagationQuery = opt
		}
	}
	return o
}

// Cmp returns true if the mounts are equal.
func (m *Mount) Cmp(v *Mount) bool {
	if v == nil {
		return false
	}
	if m.Destination != v.Destination || m.Type != v.Type || m.Source != v.Source ||
		len(m.Options) != len(v.Options) {
		return false
	}

	mOpts := make([]string, len(m.Options))
	vOpts := make([]string, len(m.Options))
	sort.Strings(mOpts)
	sort.Strings(vOpts)

	for i, o := range mOpts {
		if vOpts[i] != o {
			return false
		}
	}

	return true
}

// IsMarkedForRemoval checks if a Mount is marked for removal.
func (m *Mount) IsMarkedForRemoval() (string, bool) {
	key, marked := IsMarkedForRemoval(m.Destination)
	return key, marked
}