You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

118 lines
2.3 KiB
Go

package archiver
import (
"archive/tar"
"io"
"os"
"path/filepath"
"strings"
"github.com/xi2/xz"
)
func untgx(src string, dst string, strip bool) error {
xzFile, err := os.Open(src)
if err != nil {
return err
}
defer xzFile.Close()
var prefixToStrip string
if strip {
xzr, err := xz.NewReader(xzFile, 0)
if err != nil {
return err
}
r := tar.NewReader(xzr)
var prefix []string
for {
header, err := r.Next()
if err == io.EOF {
break
}
if err != nil {
return err
}
var dir string
if header.Typeflag != tar.TypeDir {
dir = filepath.Dir(header.Name)
} else {
continue
}
if prefix != nil {
dirSplit := strings.Split(dir, string(filepath.Separator))
i, e, dse := 0, len(prefix), len(dirSplit)
if dse < e {
e = dse
}
for i < e {
if prefix[i] != dirSplit[i] {
prefix = prefix[0:i]
break
}
i++
}
} else {
prefix = strings.Split(dir, string(filepath.Separator))
}
}
prefixToStrip = strings.Join(prefix, string(filepath.Separator))
}
xzFile.Seek(0, 0)
xzr, err := xz.NewReader(xzFile, 0)
if err != nil {
return err
}
r := tar.NewReader(xzr)
dirCache := make(map[string]bool) // todo: radix tree would perform better here
if err := os.MkdirAll(dst, 0755); err != nil {
return err
}
for {
header, err := r.Next()
if err == io.EOF {
break
}
if err != nil {
return err
}
var dir string
if header.Typeflag != tar.TypeDir {
dir = filepath.Dir(header.Name)
} else {
dir = filepath.Clean(header.Name)
if !strings.HasPrefix(dir, prefixToStrip) {
continue
}
}
dir = strings.TrimPrefix(dir, prefixToStrip)
if dir != "" && dir != "." {
cached := dirCache[dir]
if !cached {
if err := os.MkdirAll(filepath.Join(dst, dir), 0755); err != nil {
return err
}
dirCache[dir] = true
}
}
target := filepath.Join(dst, dir, filepath.Base(header.Name))
switch header.Typeflag {
case tar.TypeReg:
d, err := os.OpenFile(target,
os.O_WRONLY|os.O_CREATE|os.O_TRUNC, os.FileMode(header.Mode|0600)&0777)
if err != nil {
return err
}
_, err = io.Copy(d, r)
d.Close()
if err != nil {
return err
}
case tar.TypeSymlink:
if err = os.Symlink(header.Linkname, target); err != nil {
return err
}
}
}
return nil
}