vg_attr.go

/*
 Copyright 2024 The lvm2go 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 lvm2go

import (
	"fmt"
	"strings"
)

type VGPermissions rune

const (
	VGPermissionsWriteable VGPermissions = 'w'
	VGPermissionsReadOnly  VGPermissions = 'r'
	VGPermissionsNone      VGPermissions = '-'
)

type Resizeable rune

const (
	ResizeableTrue  Resizeable = 'z'
	ResizeableFalse Resizeable = '-'
)

type Exported rune

const (
	ExportedTrue  Exported = 'x'
	ExportedFalse Exported = '-'
)

type PartialAttr rune

const (
	PartialAttrTrue  PartialAttr = 'p'
	PartialAttrFalse PartialAttr = '-'
)

type VGAllocationPolicyAttr rune

const (
	VGAllocationPolicyAttrAnywhere   VGAllocationPolicyAttr = 'a'
	VGAllocationPolicyAttrContiguous VGAllocationPolicyAttr = 'c'
	VGAllocationPolicyAttrCling      VGAllocationPolicyAttr = 'l'
	VGAllocationPolicyAttrNormal     VGAllocationPolicyAttr = 'n'
	VGAllocationPolicyAttrNone       VGAllocationPolicyAttr = '-'
)

type ClusteredOrShared rune

const (
	ClusteredOrSharedTrue  ClusteredOrShared = 'c'
	ClusteredOrSharedFalse ClusteredOrShared = '-'
)

type VGAttributes struct {
	VGPermissions
	Resizeable
	Exported
	PartialAttr
	VGAllocationPolicyAttr
	ClusteredOrShared
}

func ParseVGAttributes(raw string) (VGAttributes, error) {
	if len(raw) != 6 {
		return VGAttributes{}, fmt.Errorf("%s is an invalid length vg_attr", raw)
	}
	return VGAttributes{
		VGPermissions:          VGPermissions(raw[0]),
		Resizeable:             Resizeable(raw[1]),
		Exported:               Exported(raw[2]),
		PartialAttr:            PartialAttr(raw[3]),
		VGAllocationPolicyAttr: VGAllocationPolicyAttr(raw[4]),
		ClusteredOrShared:      ClusteredOrShared(raw[5]),
	}, nil
}

func (attr VGAttributes) String() string {
	var builder strings.Builder
	fields := []rune{
		rune(attr.VGPermissions),
		rune(attr.Resizeable),
		rune(attr.Exported),
		rune(attr.PartialAttr),
		rune(attr.VGAllocationPolicyAttr),
		rune(attr.ClusteredOrShared),
	}
	builder.Grow(len(fields))
	for _, r := range fields {
		builder.WriteRune(r)
	}
	return builder.String()
}

func (attr VGAttributes) MarshalText() ([]byte, error) {
	return []byte(attr.String()), nil
}