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
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
// Copyright (C) 2022 Luke Shumaker <lukeshu@lukeshu.com>
//
// SPDX-License-Identifier: GPL-2.0-or-later
package btrfsutil
import (
"fmt"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsitem"
"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
"git.lukeshu.com/btrfs-progs-ng/lib/util"
)
type WalkErr struct {
TreeName string
Path btrfs.TreePath
Err error
}
func (e WalkErr) Unwrap() error { return e.Err }
func (e WalkErr) Error() string {
if len(e.Path) == 0 {
return fmt.Sprintf("%v: %v", e.TreeName, e.Err)
}
return fmt.Sprintf("%v: %v: %v", e.TreeName, e.Path, e.Err)
}
type WalkAllTreesHandler struct {
Err func(error)
// Callbacks for entire trees
PreTree func(name string, id btrfs.ObjID)
PostTree func(name string, id btrfs.ObjID)
// Callbacks for nodes or smaller
UnsafeNodes bool
btrfs.TreeWalkHandler
}
// WalkAllTrees walks all trees in a *btrfs.FS. Rather than returning
// an error, it calls errCb each time an error is encountered. The
// error will always be of type WalkErr.
func WalkAllTrees(fs *btrfs.FS, cbs WalkAllTreesHandler) {
var treeName string
handleErr := func(path btrfs.TreePath, err error) {
cbs.Err(WalkErr{
TreeName: treeName,
Path: path,
Err: err,
})
}
trees := []struct {
Name string
ID btrfs.ObjID
}{
{
Name: "root tree",
ID: btrfs.ROOT_TREE_OBJECTID,
},
{
Name: "chunk tree",
ID: btrfs.CHUNK_TREE_OBJECTID,
},
{
Name: "log tree",
ID: btrfs.TREE_LOG_OBJECTID,
},
{
Name: "block group tree",
ID: btrfs.BLOCK_GROUP_TREE_OBJECTID,
},
}
origItem := cbs.Item
cbs.Item = func(path btrfs.TreePath, item btrfs.Item) error {
if item.Head.Key.ItemType == btrfsitem.ROOT_ITEM_KEY {
trees = append(trees, struct {
Name string
ID btrfs.ObjID
}{
Name: fmt.Sprintf("tree %v (via %v %v)",
item.Head.Key.ObjectID.Format(0), treeName, path),
ID: item.Head.Key.ObjectID,
})
}
if origItem != nil {
return origItem(path, item)
}
return nil
}
if !cbs.UnsafeNodes {
origNode := cbs.Node
cbs.Node = func(path btrfs.TreePath, node *util.Ref[btrfsvol.LogicalAddr, btrfs.Node], err error) error {
if err != nil {
handleErr(path, err)
}
if node != nil && origNode != nil {
return origNode(path, node, nil)
}
return nil
}
}
for i := 0; i < len(trees); i++ {
tree := trees[i]
treeName = tree.Name
if cbs.PreTree != nil {
cbs.PreTree(treeName, tree.ID)
}
if err := fs.TreeWalk(tree.ID, cbs.TreeWalkHandler); err != nil {
handleErr(nil, err)
}
if cbs.PostTree != nil {
cbs.PostTree(treeName, tree.ID)
}
}
}
|
