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
|
// Copyright (c) 2019-2023, Sylabs Inc. All rights reserved.
// This software is licensed under a 3-clause BSD license. Please consult the
// LICENSE.md file distributed with the sources of this project regarding your
// rights to use or distribute this software.
package sources
import (
"context"
"fmt"
"os"
"syscall"
"github.com/sylabs/singularity/v4/pkg/build/types"
"github.com/sylabs/singularity/v4/pkg/image"
"github.com/sylabs/singularity/v4/pkg/sylog"
"github.com/sylabs/singularity/v4/pkg/util/archive"
"github.com/sylabs/singularity/v4/pkg/util/loop"
"golang.org/x/sys/unix"
)
// Ext3Packer holds the locations of where to back from and to, as well as image offset info
type Ext3Packer struct {
srcfile string
b *types.Bundle
img *image.Image
}
// Pack puts relevant objects in a Bundle!
func (p *Ext3Packer) Pack(context.Context) (*types.Bundle, error) {
err := unpackExt3(p.b, p.img)
if err != nil {
sylog.Errorf("while unpacking ext3 image: %v", err)
return nil, err
}
return p.b, nil
}
// unpackExt3 mounts the ext3 image using a loop device and then copies its contents to the bundle
func unpackExt3(b *types.Bundle, img *image.Image) error {
info := &unix.LoopInfo64{
Offset: img.Partitions[0].Offset,
Sizelimit: img.Partitions[0].Size,
Flags: unix.LO_FLAGS_AUTOCLEAR,
}
var number int
loopdev := &loop.Device{
MaxLoopDevices: loop.GetMaxLoopDevices(),
Info: info,
}
if err := loopdev.AttachFromFile(img.File, os.O_RDONLY, &number); err != nil {
return fmt.Errorf("while attaching image to loop device: %v", err)
}
tmpmnt, err := os.MkdirTemp(b.TmpDir, "mnt")
if err != nil {
return fmt.Errorf("while making tmp mount point: %v", err)
}
path := fmt.Sprintf("/dev/loop%d", number)
sylog.Debugf("Mounting loop device %s to %s\n", path, tmpmnt)
err = syscall.Mount(path, tmpmnt, "ext3", syscall.MS_NOSUID|syscall.MS_RDONLY|syscall.MS_NODEV, "errors=remount-ro")
if err != nil {
return fmt.Errorf("while mounting image: %v", err)
}
defer syscall.Unmount(tmpmnt, 0)
// copy filesystem into bundle rootfs
sylog.Debugf("Copying filesystem from %s to %s in Bundle\n", tmpmnt, b.RootfsPath)
err = archive.CopyWithTar(tmpmnt+`/.`, b.RootfsPath, false)
if err != nil {
return fmt.Errorf("copy Failed: %v", err)
}
return nil
}
|
