forked from containers/build
/
files.go
76 lines (66 loc) · 1.89 KB
/
files.go
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
// Copyright 2015 The appc 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 util
import (
"archive/tar"
"fmt"
"os"
"path/filepath"
"github.com/appc/spec/aci"
rkttar "github.com/coreos/rkt/pkg/tar"
"github.com/coreos/rkt/pkg/user"
)
// RmAndMkdir will remove anything at path if it exists, and then create a
// directory at path.
func RmAndMkdir(path string) error {
err := os.RemoveAll(path)
if err != nil {
return err
}
if err != nil {
return err
}
err = os.MkdirAll(path, 0755)
if err != nil {
return err
}
return nil
}
// ExtractImage will extract the contents of the image at path to the directory
// at dst. If fileMap is set, only files in it will be extracted.
func ExtractImage(path, dst string, fileMap map[string]struct{}) error {
dst, err := filepath.Abs(dst)
if err != nil {
return err
}
file, err := os.Open(path)
if err != nil {
return err
}
defer file.Close()
dr, err := aci.NewCompressedReader(file)
if err != nil {
return fmt.Errorf("error decompressing image: %v", err)
}
defer dr.Close()
uidRange := user.NewBlankUidRange()
if os.Geteuid() == 0 {
return rkttar.ExtractTar(dr, dst, true, uidRange, fileMap)
}
editor, err := rkttar.NewUidShiftingFilePermEditor(uidRange)
if err != nil {
return fmt.Errorf("error determining current user: %v", err)
}
return rkttar.ExtractTarInsecure(tar.NewReader(dr), dst, true, fileMap, editor)
}