restic/tree.go

266 lines
6.2 KiB
Go

package khepri
import (
"fmt"
"os"
"os/user"
"strconv"
"strings"
"syscall"
"time"
"github.com/fd0/khepri/backend"
"github.com/juju/arrar"
)
type Tree []*Node
type Node struct {
Name string `json:"name"`
Type string `json:"type"`
Mode os.FileMode `json:"mode,omitempty"`
ModTime time.Time `json:"mtime,omitempty"`
AccessTime time.Time `json:"atime,omitempty"`
ChangeTime time.Time `json:"ctime,omitempty"`
UID uint32 `json:"uid"`
GID uint32 `json:"gid"`
User string `json:"user,omitempty"`
Group string `json:"group,omitempty"`
Inode uint64 `json:"inode,omitempty"`
Size uint64 `json:"size,omitempty"`
Links uint64 `json:"links,omitempty"`
LinkTarget string `json:"linktarget,omitempty"`
Device uint64 `json:"device,omitempty"`
Content []backend.ID `json:"content,omitempty"`
Subtree backend.ID `json:"subtree,omitempty"`
path string
}
type Blob struct {
ID backend.ID `json:"id,omitempty"`
Size uint64 `json:"size,omitempty"`
Storage backend.ID `json:"sid,omitempty"` // encrypted ID
StorageSize uint64 `json:"ssize,omitempty"` // encrypted Size
}
type Blobs []*Blob
func (n Node) String() string {
switch n.Type {
case "file":
return fmt.Sprintf("%s %5d %5d %6d %s %s",
n.Mode, n.UID, n.GID, n.Size, n.ModTime, n.Name)
case "dir":
return fmt.Sprintf("%s %5d %5d %6d %s %s",
n.Mode|os.ModeDir, n.UID, n.GID, n.Size, n.ModTime, n.Name)
}
return fmt.Sprintf("<Node(%s) %s>", n.Type, n.Name)
}
func (t Tree) String() string {
s := []string{}
for _, n := range t {
s = append(s, n.String())
}
return strings.Join(s, "\n")
}
func (node *Node) fill_extra(path string, fi os.FileInfo) (err error) {
stat, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
return
}
node.ChangeTime = time.Unix(stat.Ctim.Unix())
node.AccessTime = time.Unix(stat.Atim.Unix())
node.UID = stat.Uid
node.GID = stat.Gid
if u, nil := user.LookupId(strconv.Itoa(int(stat.Uid))); err == nil {
node.User = u.Username
}
// TODO: implement getgrnam() or use https://github.com/kless/osutil
// if g, nil := user.LookupId(strconv.Itoa(int(stat.Uid))); err == nil {
// node.User = u.Username
// }
node.Inode = stat.Ino
switch node.Type {
case "file":
node.Size = uint64(stat.Size)
node.Links = stat.Nlink
case "dir":
// nothing to do
case "symlink":
node.LinkTarget, err = os.Readlink(path)
case "dev":
node.Device = stat.Rdev
case "chardev":
node.Device = stat.Rdev
case "fifo":
// nothing to do
case "socket":
// nothing to do
default:
panic(fmt.Sprintf("invalid node type %q", node.Type))
}
return err
}
func NodeFromFileInfo(path string, fi os.FileInfo) (*Node, error) {
node := &Node{
path: path,
Name: fi.Name(),
Mode: fi.Mode() & os.ModePerm,
ModTime: fi.ModTime(),
}
switch fi.Mode() & (os.ModeType | os.ModeCharDevice) {
case 0:
node.Type = "file"
case os.ModeDir:
node.Type = "dir"
case os.ModeSymlink:
node.Type = "symlink"
case os.ModeDevice | os.ModeCharDevice:
node.Type = "chardev"
case os.ModeDevice:
node.Type = "dev"
case os.ModeNamedPipe:
node.Type = "fifo"
case os.ModeSocket:
node.Type = "socket"
}
err := node.fill_extra(path, fi)
return node, err
}
func (node *Node) CreateAt(ch *ContentHandler, path string) error {
switch node.Type {
case "dir":
err := os.Mkdir(path, node.Mode)
if err != nil {
return arrar.Annotate(err, "Mkdir")
}
err = os.Lchown(path, int(node.UID), int(node.GID))
if err != nil {
return arrar.Annotate(err, "Lchown")
}
var utimes = []syscall.Timespec{
syscall.NsecToTimespec(node.AccessTime.UnixNano()),
syscall.NsecToTimespec(node.ModTime.UnixNano()),
}
err = syscall.UtimesNano(path, utimes)
if err != nil {
return arrar.Annotate(err, "Utimesnano")
}
case "file":
// TODO: handle hard links
f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0600)
defer f.Close()
if err != nil {
return arrar.Annotate(err, "OpenFile")
}
for _, blobid := range node.Content {
buf, err := ch.Load(backend.Blob, blobid)
if err != nil {
return arrar.Annotate(err, "Load")
}
_, err = f.Write(buf)
if err != nil {
return arrar.Annotate(err, "Write")
}
}
f.Close()
err = os.Lchown(path, int(node.UID), int(node.GID))
if err != nil {
return arrar.Annotate(err, "Lchown")
}
var utimes = []syscall.Timespec{
syscall.NsecToTimespec(node.AccessTime.UnixNano()),
syscall.NsecToTimespec(node.ModTime.UnixNano()),
}
err = syscall.UtimesNano(path, utimes)
if err != nil {
return arrar.Annotate(err, "Utimesnano")
}
case "symlink":
err := os.Symlink(node.LinkTarget, path)
if err != nil {
return arrar.Annotate(err, "Symlink")
}
err = os.Lchown(path, int(node.UID), int(node.GID))
if err != nil {
return arrar.Annotate(err, "Lchown")
}
f, err := os.OpenFile(path, O_PATH|syscall.O_NOFOLLOW, 0600)
defer f.Close()
if err != nil {
return arrar.Annotate(err, "OpenFile")
}
// TODO: Get Futimes() working on older Linux kernels (fails with 3.2.0)
// var utimes = []syscall.Timeval{
// syscall.NsecToTimeval(node.AccessTime.UnixNano()),
// syscall.NsecToTimeval(node.ModTime.UnixNano()),
// }
// err = syscall.Futimes(int(f.Fd()), utimes)
// if err != nil {
// return arrar.Annotate(err, "Futimes")
// }
return nil
case "dev":
err := syscall.Mknod(path, syscall.S_IFBLK|0600, int(node.Device))
if err != nil {
return arrar.Annotate(err, "Mknod")
}
case "chardev":
err := syscall.Mknod(path, syscall.S_IFCHR|0600, int(node.Device))
if err != nil {
return arrar.Annotate(err, "Mknod")
}
case "fifo":
err := syscall.Mkfifo(path, 0600)
if err != nil {
return arrar.Annotate(err, "Mkfifo")
}
case "socket":
// nothing to do, we do not restore sockets
default:
return fmt.Errorf("filetype %q not implemented!\n", node.Type)
}
err := os.Chmod(path, node.Mode)
if err != nil {
return arrar.Annotate(err, "Chmod")
}
err = os.Chown(path, int(node.UID), int(node.GID))
if err != nil {
return arrar.Annotate(err, "Chown")
}
err = os.Chtimes(path, node.AccessTime, node.ModTime)
if err != nil {
return arrar.Annotate(err, "Chtimes")
}
return nil
}