1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
|
// Copyright (C) 2022-2023 Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later
package btrfsprim
import (
"fmt"
"math"
"git.lukeshu.com/btrfs-progs-ng/lib/binstruct"
"git.lukeshu.com/btrfs-progs-ng/lib/containers"
)
type Key struct {
ObjectID ObjID `bin:"off=0x0, siz=0x8"` // Each tree has its own set of Object IDs.
ItemType ItemType `bin:"off=0x8, siz=0x1"`
Offset uint64 `bin:"off=0x9, siz=0x8"` // The meaning depends on the item type.
binstruct.End `bin:"off=0x11"`
}
const MaxOffset uint64 = math.MaxUint64
// mimics print-tree.c:btrfs_print_key()
func (key Key) Format(tree ObjID) string {
switch tree {
case UUID_TREE_OBJECTID:
return fmt.Sprintf("(%v %v %#08x)",
key.ObjectID.Format(tree),
key.ItemType,
key.Offset)
case ROOT_TREE_OBJECTID, QUOTA_TREE_OBJECTID:
return fmt.Sprintf("(%v %v %v)",
key.ObjectID.Format(tree),
key.ItemType,
ObjID(key.Offset).Format(tree))
default:
if key.Offset == math.MaxUint64 {
return fmt.Sprintf("(%v %v -1)",
key.ObjectID.Format(tree),
key.ItemType)
} else {
return fmt.Sprintf("(%v %v %v)",
key.ObjectID.Format(tree),
key.ItemType,
key.Offset)
}
}
}
func (key Key) String() string {
return key.Format(0)
}
var MaxKey = Key{
ObjectID: math.MaxUint64,
ItemType: math.MaxUint8,
Offset: math.MaxUint64,
}
func (key Key) Mm() Key {
switch {
case key.Offset > 0:
key.Offset--
case key.ItemType > 0:
key.ItemType--
case key.ObjectID > 0:
key.ObjectID--
}
return key
}
func (a Key) Compare(b Key) int {
if d := containers.NativeCompare(a.ObjectID, b.ObjectID); d != 0 {
return d
}
if d := containers.NativeCompare(a.ItemType, b.ItemType); d != 0 {
return d
}
return containers.NativeCompare(a.Offset, b.Offset)
}
var _ containers.Ordered[Key] = Key{}
|