docker/pkg/chrootarchive/archive.go

98 строки
3.0 KiB
Go

package chrootarchive
import (
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/idtools"
)
var chrootArchiver = &archive.Archiver{Untar: Untar}
// Untar reads a stream of bytes from `archive`, parses it as a tar archive,
// and unpacks it into the directory at `dest`.
// The archive may be compressed with one of the following algorithms:
// identity (uncompressed), gzip, bzip2, xz.
func Untar(tarArchive io.Reader, dest string, options *archive.TarOptions) error {
return untarHandler(tarArchive, dest, options, true)
}
// UntarUncompressed reads a stream of bytes from `archive`, parses it as a tar archive,
// and unpacks it into the directory at `dest`.
// The archive must be an uncompressed stream.
func UntarUncompressed(tarArchive io.Reader, dest string, options *archive.TarOptions) error {
return untarHandler(tarArchive, dest, options, false)
}
// Handler for teasing out the automatic decompression
func untarHandler(tarArchive io.Reader, dest string, options *archive.TarOptions, decompress bool) error {
if tarArchive == nil {
return fmt.Errorf("Empty archive")
}
if options == nil {
options = &archive.TarOptions{}
}
if options.ExcludePatterns == nil {
options.ExcludePatterns = []string{}
}
rootUID, rootGID, err := idtools.GetRootUIDGID(options.UIDMaps, options.GIDMaps)
if err != nil {
return err
}
dest = filepath.Clean(dest)
if _, err := os.Stat(dest); os.IsNotExist(err) {
if err := idtools.MkdirAllNewAs(dest, 0755, rootUID, rootGID); err != nil {
return err
}
}
r := ioutil.NopCloser(tarArchive)
if decompress {
decompressedArchive, err := archive.DecompressStream(tarArchive)
if err != nil {
return err
}
defer decompressedArchive.Close()
r = decompressedArchive
}
return invokeUnpack(r, dest, options)
}
// TarUntar is a convenience function which calls Tar and Untar, with the output of one piped into the other.
// If either Tar or Untar fails, TarUntar aborts and returns the error.
func TarUntar(src, dst string) error {
return chrootArchiver.TarUntar(src, dst)
}
// CopyWithTar creates a tar archive of filesystem path `src`, and
// unpacks it at filesystem path `dst`.
// The archive is streamed directly with fixed buffering and no
// intermediary disk IO.
func CopyWithTar(src, dst string) error {
return chrootArchiver.CopyWithTar(src, dst)
}
// CopyFileWithTar emulates the behavior of the 'cp' command-line
// for a single file. It copies a regular file from path `src` to
// path `dst`, and preserves all its metadata.
//
// If `dst` ends with a trailing slash '/' ('\' on Windows), the final
// destination path will be `dst/base(src)` or `dst\base(src)`
func CopyFileWithTar(src, dst string) (err error) {
return chrootArchiver.CopyFileWithTar(src, dst)
}
// UntarPath is a convenience function which looks for an archive
// at filesystem path `src`, and unpacks it at `dst`.
func UntarPath(src, dst string) error {
return chrootArchiver.UntarPath(src, dst)
}