Update fsouza/go-dockerclient. This grabs an unexpected number of dependencies.

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/MAINTAINERS

@@ -0,0 +1,2 @@
+Cristian Staretu <cristian.staretu@gmail.com> (@unclejack)
+Tibor Vass <teabee89@gmail.com> (@tiborvass)

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/README.md

@@ -0,0 +1 @@
+This code provides helper functions for dealing with archive files.

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/archive.go

@@ -0,0 +1,802 @@
+package archive
+
+import (
+	"bufio"
+	"bytes"
+	"compress/bzip2"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+
+	log "github.com/Sirupsen/logrus"
+	"github.com/docker/docker/pkg/fileutils"
+	"github.com/docker/docker/pkg/pools"
+	"github.com/docker/docker/pkg/promise"
+	"github.com/docker/docker/pkg/system"
+)
+
+type (
+	Archive       io.ReadCloser
+	ArchiveReader io.Reader
+	Compression   int
+	TarOptions    struct {
+		Includes    []string
+		Excludes    []string
+		Compression Compression
+		NoLchown    bool
+		Name        string
+	}
+
+	// Archiver allows the reuse of most utility functions of this package
+	// with a pluggable Untar function.
+	Archiver struct {
+		Untar func(io.Reader, string, *TarOptions) error
+	}
+
+	// breakoutError is used to differentiate errors related to breaking out
+	// When testing archive breakout in the unit tests, this error is expected
+	// in order for the test to pass.
+	breakoutError error
+)
+
+var (
+	ErrNotImplemented = errors.New("Function not implemented")
+	defaultArchiver   = &Archiver{Untar}
+)
+
+const (
+	Uncompressed Compression = iota
+	Bzip2
+	Gzip
+	Xz
+)
+
+func IsArchive(header []byte) bool {
+	compression := DetectCompression(header)
+	if compression != Uncompressed {
+		return true
+	}
+	r := tar.NewReader(bytes.NewBuffer(header))
+	_, err := r.Next()
+	return err == nil
+}
+
+func DetectCompression(source []byte) Compression {
+	for compression, m := range map[Compression][]byte{
+		Bzip2: {0x42, 0x5A, 0x68},
+		Gzip:  {0x1F, 0x8B, 0x08},
+		Xz:    {0xFD, 0x37, 0x7A, 0x58, 0x5A, 0x00},
+	} {
+		if len(source) < len(m) {
+			log.Debugf("Len too short")
+			continue
+		}
+		if bytes.Compare(m, source[:len(m)]) == 0 {
+			return compression
+		}
+	}
+	return Uncompressed
+}
+
+func xzDecompress(archive io.Reader) (io.ReadCloser, error) {
+	args := []string{"xz", "-d", "-c", "-q"}
+
+	return CmdStream(exec.Command(args[0], args[1:]...), archive)
+}
+
+func DecompressStream(archive io.Reader) (io.ReadCloser, error) {
+	p := pools.BufioReader32KPool
+	buf := p.Get(archive)
+	bs, err := buf.Peek(10)
+	if err != nil {
+		return nil, err
+	}
+	log.Debugf("[tar autodetect] n: %v", bs)
+
+	compression := DetectCompression(bs)
+	switch compression {
+	case Uncompressed:
+		readBufWrapper := p.NewReadCloserWrapper(buf, buf)
+		return readBufWrapper, nil
+	case Gzip:
+		gzReader, err := gzip.NewReader(buf)
+		if err != nil {
+			return nil, err
+		}
+		readBufWrapper := p.NewReadCloserWrapper(buf, gzReader)
+		return readBufWrapper, nil
+	case Bzip2:
+		bz2Reader := bzip2.NewReader(buf)
+		readBufWrapper := p.NewReadCloserWrapper(buf, bz2Reader)
+		return readBufWrapper, nil
+	case Xz:
+		xzReader, err := xzDecompress(buf)
+		if err != nil {
+			return nil, err
+		}
+		readBufWrapper := p.NewReadCloserWrapper(buf, xzReader)
+		return readBufWrapper, nil
+	default:
+		return nil, fmt.Errorf("Unsupported compression format %s", (&compression).Extension())
+	}
+}
+
+func CompressStream(dest io.WriteCloser, compression Compression) (io.WriteCloser, error) {
+	p := pools.BufioWriter32KPool
+	buf := p.Get(dest)
+	switch compression {
+	case Uncompressed:
+		writeBufWrapper := p.NewWriteCloserWrapper(buf, buf)
+		return writeBufWrapper, nil
+	case Gzip:
+		gzWriter := gzip.NewWriter(dest)
+		writeBufWrapper := p.NewWriteCloserWrapper(buf, gzWriter)
+		return writeBufWrapper, nil
+	case Bzip2, Xz:
+		// archive/bzip2 does not support writing, and there is no xz support at all
+		// However, this is not a problem as docker only currently generates gzipped tars
+		return nil, fmt.Errorf("Unsupported compression format %s", (&compression).Extension())
+	default:
+		return nil, fmt.Errorf("Unsupported compression format %s", (&compression).Extension())
+	}
+}
+
+func (compression *Compression) Extension() string {
+	switch *compression {
+	case Uncompressed:
+		return "tar"
+	case Bzip2:
+		return "tar.bz2"
+	case Gzip:
+		return "tar.gz"
+	case Xz:
+		return "tar.xz"
+	}
+	return ""
+}
+
+type tarAppender struct {
+	TarWriter *tar.Writer
+	Buffer    *bufio.Writer
+
+	// for hardlink mapping
+	SeenFiles map[uint64]string
+}
+
+func (ta *tarAppender) addTarFile(path, name string) error {
+	fi, err := os.Lstat(path)
+	if err != nil {
+		return err
+	}
+
+	link := ""
+	if fi.Mode()&os.ModeSymlink != 0 {
+		if link, err = os.Readlink(path); err != nil {
+			return err
+		}
+	}
+
+	hdr, err := tar.FileInfoHeader(fi, link)
+	if err != nil {
+		return err
+	}
+
+	if fi.IsDir() && !strings.HasSuffix(name, "/") {
+		name = name + "/"
+	}
+
+	hdr.Name = name
+
+	nlink, inode, err := setHeaderForSpecialDevice(hdr, ta, name, fi.Sys())
+	if err != nil {
+		return err
+	}
+
+	// if it's a regular file and has more than 1 link,
+	// it's hardlinked, so set the type flag accordingly
+	if fi.Mode().IsRegular() && nlink > 1 {
+		// a link should have a name that it links too
+		// and that linked name should be first in the tar archive
+		if oldpath, ok := ta.SeenFiles[inode]; ok {
+			hdr.Typeflag = tar.TypeLink
+			hdr.Linkname = oldpath
+			hdr.Size = 0 // This Must be here for the writer math to add up!
+		} else {
+			ta.SeenFiles[inode] = name
+		}
+	}
+
+	capability, _ := system.Lgetxattr(path, "security.capability")
+	if capability != nil {
+		hdr.Xattrs = make(map[string]string)
+		hdr.Xattrs["security.capability"] = string(capability)
+	}
+
+	if err := ta.TarWriter.WriteHeader(hdr); err != nil {
+		return err
+	}
+
+	if hdr.Typeflag == tar.TypeReg {
+		file, err := os.Open(path)
+		if err != nil {
+			return err
+		}
+
+		ta.Buffer.Reset(ta.TarWriter)
+		defer ta.Buffer.Reset(nil)
+		_, err = io.Copy(ta.Buffer, file)
+		file.Close()
+		if err != nil {
+			return err
+		}
+		err = ta.Buffer.Flush()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, Lchown bool) error {
+	// hdr.Mode is in linux format, which we can use for sycalls,
+	// but for os.Foo() calls we need the mode converted to os.FileMode,
+	// so use hdrInfo.Mode() (they differ for e.g. setuid bits)
+	hdrInfo := hdr.FileInfo()
+
+	switch hdr.Typeflag {
+	case tar.TypeDir:
+		// Create directory unless it exists as a directory already.
+		// In that case we just want to merge the two
+		if fi, err := os.Lstat(path); !(err == nil && fi.IsDir()) {
+			if err := os.Mkdir(path, hdrInfo.Mode()); err != nil {
+				return err
+			}
+		}
+
+	case tar.TypeReg, tar.TypeRegA:
+		// Source is regular file
+		file, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, hdrInfo.Mode())
+		if err != nil {
+			return err
+		}
+		if _, err := io.Copy(file, reader); err != nil {
+			file.Close()
+			return err
+		}
+		file.Close()
+
+	case tar.TypeBlock, tar.TypeChar, tar.TypeFifo:
+		mode := uint32(hdr.Mode & 07777)
+		switch hdr.Typeflag {
+		case tar.TypeBlock:
+			mode |= syscall.S_IFBLK
+		case tar.TypeChar:
+			mode |= syscall.S_IFCHR
+		case tar.TypeFifo:
+			mode |= syscall.S_IFIFO
+		}
+
+		if err := system.Mknod(path, mode, int(system.Mkdev(hdr.Devmajor, hdr.Devminor))); err != nil {
+			return err
+		}
+
+	case tar.TypeLink:
+		targetPath := filepath.Join(extractDir, hdr.Linkname)
+		// check for hardlink breakout
+		if !strings.HasPrefix(targetPath, extractDir) {
+			return breakoutError(fmt.Errorf("invalid hardlink %q -> %q", targetPath, hdr.Linkname))
+		}
+		if err := os.Link(targetPath, path); err != nil {
+			return err
+		}
+
+	case tar.TypeSymlink:
+		// 	path 				-> hdr.Linkname = targetPath
+		// e.g. /extractDir/path/to/symlink 	-> ../2/file	= /extractDir/path/2/file
+		targetPath := filepath.Join(filepath.Dir(path), hdr.Linkname)
+
+		// the reason we don't need to check symlinks in the path (with FollowSymlinkInScope) is because
+		// that symlink would first have to be created, which would be caught earlier, at this very check:
+		if !strings.HasPrefix(targetPath, extractDir) {
+			return breakoutError(fmt.Errorf("invalid symlink %q -> %q", path, hdr.Linkname))
+		}
+		if err := os.Symlink(hdr.Linkname, path); err != nil {
+			return err
+		}
+
+	case tar.TypeXGlobalHeader:
+		log.Debugf("PAX Global Extended Headers found and ignored")
+		return nil
+
+	default:
+		return fmt.Errorf("Unhandled tar header type %d\n", hdr.Typeflag)
+	}
+
+	if err := os.Lchown(path, hdr.Uid, hdr.Gid); err != nil && Lchown {
+		return err
+	}
+
+	for key, value := range hdr.Xattrs {
+		if err := system.Lsetxattr(path, key, []byte(value), 0); err != nil {
+			return err
+		}
+	}
+
+	// There is no LChmod, so ignore mode for symlink. Also, this
+	// must happen after chown, as that can modify the file mode
+	if hdr.Typeflag != tar.TypeSymlink {
+		if err := os.Chmod(path, hdrInfo.Mode()); err != nil {
+			return err
+		}
+	}
+
+	ts := []syscall.Timespec{timeToTimespec(hdr.AccessTime), timeToTimespec(hdr.ModTime)}
+	// syscall.UtimesNano doesn't support a NOFOLLOW flag atm, and
+	if hdr.Typeflag != tar.TypeSymlink {
+		if err := system.UtimesNano(path, ts); err != nil && err != system.ErrNotSupportedPlatform {
+			return err
+		}
+	} else {
+		if err := system.LUtimesNano(path, ts); err != nil && err != system.ErrNotSupportedPlatform {
+			return err
+		}
+	}
+	return nil
+}
+
+// Tar creates an archive from the directory at `path`, and returns it as a
+// stream of bytes.
+func Tar(path string, compression Compression) (io.ReadCloser, error) {
+	return TarWithOptions(path, &TarOptions{Compression: compression})
+}
+
+func escapeName(name string) string {
+	escaped := make([]byte, 0)
+	for i, c := range []byte(name) {
+		if i == 0 && c == '/' {
+			continue
+		}
+		// all printable chars except "-" which is 0x2d
+		if (0x20 <= c && c <= 0x7E) && c != 0x2d {
+			escaped = append(escaped, c)
+		} else {
+			escaped = append(escaped, fmt.Sprintf("\\%03o", c)...)
+		}
+	}
+	return string(escaped)
+}
+
+// TarWithOptions creates an archive from the directory at `path`, only including files whose relative
+// paths are included in `options.Includes` (if non-nil) or not in `options.Excludes`.
+func TarWithOptions(srcPath string, options *TarOptions) (io.ReadCloser, error) {
+	pipeReader, pipeWriter := io.Pipe()
+
+	compressWriter, err := CompressStream(pipeWriter, options.Compression)
+	if err != nil {
+		return nil, err
+	}
+
+	go func() {
+		ta := &tarAppender{
+			TarWriter: tar.NewWriter(compressWriter),
+			Buffer:    pools.BufioWriter32KPool.Get(nil),
+			SeenFiles: make(map[uint64]string),
+		}
+		// this buffer is needed for the duration of this piped stream
+		defer pools.BufioWriter32KPool.Put(ta.Buffer)
+
+		// In general we log errors here but ignore them because
+		// during e.g. a diff operation the container can continue
+		// mutating the filesystem and we can see transient errors
+		// from this
+
+		if options.Includes == nil {
+			options.Includes = []string{"."}
+		}
+
+		var renamedRelFilePath string // For when tar.Options.Name is set
+		for _, include := range options.Includes {
+			filepath.Walk(filepath.Join(srcPath, include), func(filePath string, f os.FileInfo, err error) error {
+				if err != nil {
+					log.Debugf("Tar: Can't stat file %s to tar: %s", srcPath, err)
+					return nil
+				}
+
+				relFilePath, err := filepath.Rel(srcPath, filePath)
+				if err != nil || (relFilePath == "." && f.IsDir()) {
+					// Error getting relative path OR we are looking
+					// at the root path. Skip in both situations.
+					return nil
+				}
+
+				skip, err := fileutils.Matches(relFilePath, options.Excludes)
+				if err != nil {
+					log.Debugf("Error matching %s", relFilePath, err)
+					return err
+				}
+
+				if skip {
+					if f.IsDir() {
+						return filepath.SkipDir
+					}
+					return nil
+				}
+
+				// Rename the base resource
+				if options.Name != "" && filePath == srcPath+"/"+filepath.Base(relFilePath) {
+					renamedRelFilePath = relFilePath
+				}
+				// Set this to make sure the items underneath also get renamed
+				if options.Name != "" {
+					relFilePath = strings.Replace(relFilePath, renamedRelFilePath, options.Name, 1)
+				}
+
+				if err := ta.addTarFile(filePath, relFilePath); err != nil {
+					log.Debugf("Can't add file %s to tar: %s", srcPath, err)
+				}
+				return nil
+			})
+		}
+
+		// Make sure to check the error on Close.
+		if err := ta.TarWriter.Close(); err != nil {
+			log.Debugf("Can't close tar writer: %s", err)
+		}
+		if err := compressWriter.Close(); err != nil {
+			log.Debugf("Can't close compress writer: %s", err)
+		}
+		if err := pipeWriter.Close(); err != nil {
+			log.Debugf("Can't close pipe writer: %s", err)
+		}
+	}()
+
+	return pipeReader, nil
+}
+
+func Unpack(decompressedArchive io.Reader, dest string, options *TarOptions) error {
+	tr := tar.NewReader(decompressedArchive)
+	trBuf := pools.BufioReader32KPool.Get(nil)
+	defer pools.BufioReader32KPool.Put(trBuf)
+
+	var dirs []*tar.Header
+
+	// Iterate through the files in the archive.
+loop:
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			// end of tar archive
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		// Normalize name, for safety and for a simple is-root check
+		// This keeps "../" as-is, but normalizes "/../" to "/"
+		hdr.Name = filepath.Clean(hdr.Name)
+
+		for _, exclude := range options.Excludes {
+			if strings.HasPrefix(hdr.Name, exclude) {
+				continue loop
+			}
+		}
+
+		if !strings.HasSuffix(hdr.Name, "/") {
+			// Not the root directory, ensure that the parent directory exists
+			parent := filepath.Dir(hdr.Name)
+			parentPath := filepath.Join(dest, parent)
+			if _, err := os.Lstat(parentPath); err != nil && os.IsNotExist(err) {
+				err = os.MkdirAll(parentPath, 0777)
+				if err != nil {
+					return err
+				}
+			}
+		}
+
+		path := filepath.Join(dest, hdr.Name)
+		rel, err := filepath.Rel(dest, path)
+		if err != nil {
+			return err
+		}
+		if strings.HasPrefix(rel, "..") {
+			return breakoutError(fmt.Errorf("%q is outside of %q", hdr.Name, dest))
+		}
+
+		// If path exits we almost always just want to remove and replace it
+		// The only exception is when it is a directory *and* the file from
+		// the layer is also a directory. Then we want to merge them (i.e.
+		// just apply the metadata from the layer).
+		if fi, err := os.Lstat(path); err == nil {
+			if fi.IsDir() && hdr.Name == "." {
+				continue
+			}
+			if !(fi.IsDir() && hdr.Typeflag == tar.TypeDir) {
+				if err := os.RemoveAll(path); err != nil {
+					return err
+				}
+			}
+		}
+		trBuf.Reset(tr)
+		if err := createTarFile(path, dest, hdr, trBuf, !options.NoLchown); err != nil {
+			return err
+		}
+
+		// Directory mtimes must be handled at the end to avoid further
+		// file creation in them to modify the directory mtime
+		if hdr.Typeflag == tar.TypeDir {
+			dirs = append(dirs, hdr)
+		}
+	}
+
+	for _, hdr := range dirs {
+		path := filepath.Join(dest, hdr.Name)
+		ts := []syscall.Timespec{timeToTimespec(hdr.AccessTime), timeToTimespec(hdr.ModTime)}
+		if err := syscall.UtimesNano(path, ts); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// 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.
+// FIXME: specify behavior when target path exists vs. doesn't exist.
+func Untar(archive io.Reader, dest string, options *TarOptions) error {
+	if archive == nil {
+		return fmt.Errorf("Empty archive")
+	}
+	dest = filepath.Clean(dest)
+	if options == nil {
+		options = &TarOptions{}
+	}
+	if options.Excludes == nil {
+		options.Excludes = []string{}
+	}
+	decompressedArchive, err := DecompressStream(archive)
+	if err != nil {
+		return err
+	}
+	defer decompressedArchive.Close()
+	return Unpack(decompressedArchive, dest, options)
+}
+
+func (archiver *Archiver) TarUntar(src, dst string) error {
+	log.Debugf("TarUntar(%s %s)", src, dst)
+	archive, err := TarWithOptions(src, &TarOptions{Compression: Uncompressed})
+	if err != nil {
+		return err
+	}
+	defer archive.Close()
+	return archiver.Untar(archive, dst, nil)
+}
+
+// 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 defaultArchiver.TarUntar(src, dst)
+}
+
+func (archiver *Archiver) UntarPath(src, dst string) error {
+	archive, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer archive.Close()
+	if err := archiver.Untar(archive, dst, nil); err != nil {
+		return err
+	}
+	return nil
+}
+
+// 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 defaultArchiver.UntarPath(src, dst)
+}
+
+func (archiver *Archiver) CopyWithTar(src, dst string) error {
+	srcSt, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	if !srcSt.IsDir() {
+		return archiver.CopyFileWithTar(src, dst)
+	}
+	// Create dst, copy src's content into it
+	log.Debugf("Creating dest directory: %s", dst)
+	if err := os.MkdirAll(dst, 0755); err != nil && !os.IsExist(err) {
+		return err
+	}
+	log.Debugf("Calling TarUntar(%s, %s)", src, dst)
+	return archiver.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 defaultArchiver.CopyWithTar(src, dst)
+}
+
+func (archiver *Archiver) CopyFileWithTar(src, dst string) (err error) {
+	log.Debugf("CopyFileWithTar(%s, %s)", src, dst)
+	srcSt, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	if srcSt.IsDir() {
+		return fmt.Errorf("Can't copy a directory")
+	}
+	// Clean up the trailing /
+	if dst[len(dst)-1] == '/' {
+		dst = path.Join(dst, filepath.Base(src))
+	}
+	// Create the holding directory if necessary
+	if err := os.MkdirAll(filepath.Dir(dst), 0700); err != nil && !os.IsExist(err) {
+		return err
+	}
+
+	r, w := io.Pipe()
+	errC := promise.Go(func() error {
+		defer w.Close()
+
+		srcF, err := os.Open(src)
+		if err != nil {
+			return err
+		}
+		defer srcF.Close()
+
+		hdr, err := tar.FileInfoHeader(srcSt, "")
+		if err != nil {
+			return err
+		}
+		hdr.Name = filepath.Base(dst)
+		tw := tar.NewWriter(w)
+		defer tw.Close()
+		if err := tw.WriteHeader(hdr); err != nil {
+			return err
+		}
+		if _, err := io.Copy(tw, srcF); err != nil {
+			return err
+		}
+		return nil
+	})
+	defer func() {
+		if er := <-errC; err != nil {
+			err = er
+		}
+	}()
+	return archiver.Untar(r, filepath.Dir(dst), nil)
+}
+
+// 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 '/', the final destination path
+// will be `dst/base(src)`.
+func CopyFileWithTar(src, dst string) (err error) {
+	return defaultArchiver.CopyFileWithTar(src, dst)
+}
+
+// CmdStream executes a command, and returns its stdout as a stream.
+// If the command fails to run or doesn't complete successfully, an error
+// will be returned, including anything written on stderr.
+func CmdStream(cmd *exec.Cmd, input io.Reader) (io.ReadCloser, error) {
+	if input != nil {
+		stdin, err := cmd.StdinPipe()
+		if err != nil {
+			return nil, err
+		}
+		// Write stdin if any
+		go func() {
+			io.Copy(stdin, input)
+			stdin.Close()
+		}()
+	}
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		return nil, err
+	}
+	pipeR, pipeW := io.Pipe()
+	errChan := make(chan []byte)
+	// Collect stderr, we will use it in case of an error
+	go func() {
+		errText, e := ioutil.ReadAll(stderr)
+		if e != nil {
+			errText = []byte("(...couldn't fetch stderr: " + e.Error() + ")")
+		}
+		errChan <- errText
+	}()
+	// Copy stdout to the returned pipe
+	go func() {
+		_, err := io.Copy(pipeW, stdout)
+		if err != nil {
+			pipeW.CloseWithError(err)
+		}
+		errText := <-errChan
+		if err := cmd.Wait(); err != nil {
+			pipeW.CloseWithError(fmt.Errorf("%s: %s", err, errText))
+		} else {
+			pipeW.Close()
+		}
+	}()
+	// Run the command and return the pipe
+	if err := cmd.Start(); err != nil {
+		return nil, err
+	}
+	return pipeR, nil
+}
+
+// NewTempArchive reads the content of src into a temporary file, and returns the contents
+// of that file as an archive. The archive can only be read once - as soon as reading completes,
+// the file will be deleted.
+func NewTempArchive(src Archive, dir string) (*TempArchive, error) {
+	f, err := ioutil.TempFile(dir, "")
+	if err != nil {
+		return nil, err
+	}
+	if _, err := io.Copy(f, src); err != nil {
+		return nil, err
+	}
+	if err = f.Sync(); err != nil {
+		return nil, err
+	}
+	if _, err := f.Seek(0, 0); err != nil {
+		return nil, err
+	}
+	st, err := f.Stat()
+	if err != nil {
+		return nil, err
+	}
+	size := st.Size()
+	return &TempArchive{File: f, Size: size}, nil
+}
+
+type TempArchive struct {
+	*os.File
+	Size   int64 // Pre-computed from Stat().Size() as a convenience
+	read   int64
+	closed bool
+}
+
+// Close closes the underlying file if it's still open, or does a no-op
+// to allow callers to try to close the TempArchive multiple times safely.
+func (archive *TempArchive) Close() error {
+	if archive.closed {
+		return nil
+	}
+
+	archive.closed = true
+
+	return archive.File.Close()
+}
+
+func (archive *TempArchive) Read(data []byte) (int, error) {
+	n, err := archive.File.Read(data)
+	archive.read += int64(n)
+	if err != nil || archive.read == archive.Size {
+		archive.Close()
+		os.Remove(archive.File.Name())
+	}
+	return n, err
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/archive_test.go

@@ -0,0 +1,625 @@
+package archive
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strings"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+)
+
+func TestCmdStreamLargeStderr(t *testing.T) {
+	cmd := exec.Command("/bin/sh", "-c", "dd if=/dev/zero bs=1k count=1000 of=/dev/stderr; echo hello")
+	out, err := CmdStream(cmd, nil)
+	if err != nil {
+		t.Fatalf("Failed to start command: %s", err)
+	}
+	errCh := make(chan error)
+	go func() {
+		_, err := io.Copy(ioutil.Discard, out)
+		errCh <- err
+	}()
+	select {
+	case err := <-errCh:
+		if err != nil {
+			t.Fatalf("Command should not have failed (err=%.100s...)", err)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatalf("Command did not complete in 5 seconds; probable deadlock")
+	}
+}
+
+func TestCmdStreamBad(t *testing.T) {
+	badCmd := exec.Command("/bin/sh", "-c", "echo hello; echo >&2 error couldn\\'t reverse the phase pulser; exit 1")
+	out, err := CmdStream(badCmd, nil)
+	if err != nil {
+		t.Fatalf("Failed to start command: %s", err)
+	}
+	if output, err := ioutil.ReadAll(out); err == nil {
+		t.Fatalf("Command should have failed")
+	} else if err.Error() != "exit status 1: error couldn't reverse the phase pulser\n" {
+		t.Fatalf("Wrong error value (%s)", err)
+	} else if s := string(output); s != "hello\n" {
+		t.Fatalf("Command output should be '%s', not '%s'", "hello\\n", output)
+	}
+}
+
+func TestCmdStreamGood(t *testing.T) {
+	cmd := exec.Command("/bin/sh", "-c", "echo hello; exit 0")
+	out, err := CmdStream(cmd, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if output, err := ioutil.ReadAll(out); err != nil {
+		t.Fatalf("Command should not have failed (err=%s)", err)
+	} else if s := string(output); s != "hello\n" {
+		t.Fatalf("Command output should be '%s', not '%s'", "hello\\n", output)
+	}
+}
+
+func TestTarFiles(t *testing.T) {
+	// try without hardlinks
+	if err := checkNoChanges(1000, false); err != nil {
+		t.Fatal(err)
+	}
+	// try with hardlinks
+	if err := checkNoChanges(1000, true); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func checkNoChanges(fileNum int, hardlinks bool) error {
+	srcDir, err := ioutil.TempDir("", "docker-test-srcDir")
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(srcDir)
+
+	destDir, err := ioutil.TempDir("", "docker-test-destDir")
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(destDir)
+
+	_, err = prepareUntarSourceDirectory(fileNum, srcDir, hardlinks)
+	if err != nil {
+		return err
+	}
+
+	err = TarUntar(srcDir, destDir)
+	if err != nil {
+		return err
+	}
+
+	changes, err := ChangesDirs(destDir, srcDir)
+	if err != nil {
+		return err
+	}
+	if len(changes) > 0 {
+		return fmt.Errorf("with %d files and %v hardlinks: expected 0 changes, got %d", fileNum, hardlinks, len(changes))
+	}
+	return nil
+}
+
+func tarUntar(t *testing.T, origin string, options *TarOptions) ([]Change, error) {
+	archive, err := TarWithOptions(origin, options)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer archive.Close()
+
+	buf := make([]byte, 10)
+	if _, err := archive.Read(buf); err != nil {
+		return nil, err
+	}
+	wrap := io.MultiReader(bytes.NewReader(buf), archive)
+
+	detectedCompression := DetectCompression(buf)
+	compression := options.Compression
+	if detectedCompression.Extension() != compression.Extension() {
+		return nil, fmt.Errorf("Wrong compression detected. Actual compression: %s, found %s", compression.Extension(), detectedCompression.Extension())
+	}
+
+	tmp, err := ioutil.TempDir("", "docker-test-untar")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(tmp)
+	if err := Untar(wrap, tmp, nil); err != nil {
+		return nil, err
+	}
+	if _, err := os.Stat(tmp); err != nil {
+		return nil, err
+	}
+
+	return ChangesDirs(origin, tmp)
+}
+
+func TestTarUntar(t *testing.T) {
+	origin, err := ioutil.TempDir("", "docker-test-untar-origin")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(origin)
+	if err := ioutil.WriteFile(path.Join(origin, "1"), []byte("hello world"), 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(path.Join(origin, "2"), []byte("welcome!"), 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(path.Join(origin, "3"), []byte("will be ignored"), 0700); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, c := range []Compression{
+		Uncompressed,
+		Gzip,
+	} {
+		changes, err := tarUntar(t, origin, &TarOptions{
+			Compression: c,
+			Excludes:    []string{"3"},
+		})
+
+		if err != nil {
+			t.Fatalf("Error tar/untar for compression %s: %s", c.Extension(), err)
+		}
+
+		if len(changes) != 1 || changes[0].Path != "/3" {
+			t.Fatalf("Unexpected differences after tarUntar: %v", changes)
+		}
+	}
+}
+
+func TestTarWithOptions(t *testing.T) {
+	origin, err := ioutil.TempDir("", "docker-test-untar-origin")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(origin)
+	if err := ioutil.WriteFile(path.Join(origin, "1"), []byte("hello world"), 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(path.Join(origin, "2"), []byte("welcome!"), 0700); err != nil {
+		t.Fatal(err)
+	}
+
+	cases := []struct {
+		opts       *TarOptions
+		numChanges int
+	}{
+		{&TarOptions{Includes: []string{"1"}}, 1},
+		{&TarOptions{Excludes: []string{"2"}}, 1},
+	}
+	for _, testCase := range cases {
+		changes, err := tarUntar(t, origin, testCase.opts)
+		if err != nil {
+			t.Fatalf("Error tar/untar when testing inclusion/exclusion: %s", err)
+		}
+		if len(changes) != testCase.numChanges {
+			t.Errorf("Expected %d changes, got %d for %+v:",
+				testCase.numChanges, len(changes), testCase.opts)
+		}
+	}
+}
+
+// Some tar archives such as http://haproxy.1wt.eu/download/1.5/src/devel/haproxy-1.5-dev21.tar.gz
+// use PAX Global Extended Headers.
+// Failing prevents the archives from being uncompressed during ADD
+func TestTypeXGlobalHeaderDoesNotFail(t *testing.T) {
+	hdr := tar.Header{Typeflag: tar.TypeXGlobalHeader}
+	tmpDir, err := ioutil.TempDir("", "docker-test-archive-pax-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tmpDir)
+	err = createTarFile(filepath.Join(tmpDir, "pax_global_header"), tmpDir, &hdr, nil, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+// Some tar have both GNU specific (huge uid) and Ustar specific (long name) things.
+// Not supposed to happen (should use PAX instead of Ustar for long name) but it does and it should still work.
+func TestUntarUstarGnuConflict(t *testing.T) {
+	f, err := os.Open("testdata/broken.tar")
+	if err != nil {
+		t.Fatal(err)
+	}
+	found := false
+	tr := tar.NewReader(f)
+	// Iterate through the files in the archive.
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			// end of tar archive
+			break
+		}
+		if err != nil {
+			t.Fatal(err)
+		}
+		if hdr.Name == "root/.cpanm/work/1395823785.24209/Plack-1.0030/blib/man3/Plack::Middleware::LighttpdScriptNameFix.3pm" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatalf("%s not found in the archive", "root/.cpanm/work/1395823785.24209/Plack-1.0030/blib/man3/Plack::Middleware::LighttpdScriptNameFix.3pm")
+	}
+}
+
+func TestTarWithHardLink(t *testing.T) {
+	origin, err := ioutil.TempDir("", "docker-test-tar-hardlink")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(origin)
+	if err := ioutil.WriteFile(path.Join(origin, "1"), []byte("hello world"), 0700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Link(path.Join(origin, "1"), path.Join(origin, "2")); err != nil {
+		t.Fatal(err)
+	}
+
+	var i1, i2 uint64
+	if i1, err = getNlink(path.Join(origin, "1")); err != nil {
+		t.Fatal(err)
+	}
+	// sanity check that we can hardlink
+	if i1 != 2 {
+		t.Skipf("skipping since hardlinks don't work here; expected 2 links, got %d", i1)
+	}
+
+	dest, err := ioutil.TempDir("", "docker-test-tar-hardlink-dest")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dest)
+
+	// we'll do this in two steps to separate failure
+	fh, err := Tar(origin, Uncompressed)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// ensure we can read the whole thing with no error, before writing back out
+	buf, err := ioutil.ReadAll(fh)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	bRdr := bytes.NewReader(buf)
+	err = Untar(bRdr, dest, &TarOptions{Compression: Uncompressed})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if i1, err = getInode(path.Join(dest, "1")); err != nil {
+		t.Fatal(err)
+	}
+	if i2, err = getInode(path.Join(dest, "2")); err != nil {
+		t.Fatal(err)
+	}
+
+	if i1 != i2 {
+		t.Errorf("expected matching inodes, but got %d and %d", i1, i2)
+	}
+}
+
+func getNlink(path string) (uint64, error) {
+	stat, err := os.Stat(path)
+	if err != nil {
+		return 0, err
+	}
+	statT, ok := stat.Sys().(*syscall.Stat_t)
+	if !ok {
+		return 0, fmt.Errorf("expected type *syscall.Stat_t, got %t", stat.Sys())
+	}
+	return statT.Nlink, nil
+}
+
+func getInode(path string) (uint64, error) {
+	stat, err := os.Stat(path)
+	if err != nil {
+		return 0, err
+	}
+	statT, ok := stat.Sys().(*syscall.Stat_t)
+	if !ok {
+		return 0, fmt.Errorf("expected type *syscall.Stat_t, got %t", stat.Sys())
+	}
+	return statT.Ino, nil
+}
+
+func prepareUntarSourceDirectory(numberOfFiles int, targetPath string, makeLinks bool) (int, error) {
+	fileData := []byte("fooo")
+	for n := 0; n < numberOfFiles; n++ {
+		fileName := fmt.Sprintf("file-%d", n)
+		if err := ioutil.WriteFile(path.Join(targetPath, fileName), fileData, 0700); err != nil {
+			return 0, err
+		}
+		if makeLinks {
+			if err := os.Link(path.Join(targetPath, fileName), path.Join(targetPath, fileName+"-link")); err != nil {
+				return 0, err
+			}
+		}
+	}
+	totalSize := numberOfFiles * len(fileData)
+	return totalSize, nil
+}
+
+func BenchmarkTarUntar(b *testing.B) {
+	origin, err := ioutil.TempDir("", "docker-test-untar-origin")
+	if err != nil {
+		b.Fatal(err)
+	}
+	tempDir, err := ioutil.TempDir("", "docker-test-untar-destination")
+	if err != nil {
+		b.Fatal(err)
+	}
+	target := path.Join(tempDir, "dest")
+	n, err := prepareUntarSourceDirectory(100, origin, false)
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer os.RemoveAll(origin)
+	defer os.RemoveAll(tempDir)
+
+	b.ResetTimer()
+	b.SetBytes(int64(n))
+	for n := 0; n < b.N; n++ {
+		err := TarUntar(origin, target)
+		if err != nil {
+			b.Fatal(err)
+		}
+		os.RemoveAll(target)
+	}
+}
+
+func BenchmarkTarUntarWithLinks(b *testing.B) {
+	origin, err := ioutil.TempDir("", "docker-test-untar-origin")
+	if err != nil {
+		b.Fatal(err)
+	}
+	tempDir, err := ioutil.TempDir("", "docker-test-untar-destination")
+	if err != nil {
+		b.Fatal(err)
+	}
+	target := path.Join(tempDir, "dest")
+	n, err := prepareUntarSourceDirectory(100, origin, true)
+	if err != nil {
+		b.Fatal(err)
+	}
+	defer os.RemoveAll(origin)
+	defer os.RemoveAll(tempDir)
+
+	b.ResetTimer()
+	b.SetBytes(int64(n))
+	for n := 0; n < b.N; n++ {
+		err := TarUntar(origin, target)
+		if err != nil {
+			b.Fatal(err)
+		}
+		os.RemoveAll(target)
+	}
+}
+
+func TestUntarInvalidFilenames(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{
+			{
+				Name:     "../victim/dotdot",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{
+			{
+				// Note the leading slash
+				Name:     "/../victim/slash-dotdot",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("untar", "docker-TestUntarInvalidFilenames", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}
+
+func TestUntarInvalidHardlink(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{ // try reading victim/hello (../)
+			{
+				Name:     "dotdot",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (/../)
+			{
+				Name:     "slash-dotdot",
+				Typeflag: tar.TypeLink,
+				// Note the leading slash
+				Linkname: "/../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try writing victim/file
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim/file",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (hardlink, symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "symlink",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // Try reading victim/hello (hardlink, hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "hardlink",
+				Typeflag: tar.TypeLink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // Try removing victim directory (hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("untar", "docker-TestUntarInvalidHardlink", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}
+
+func TestUntarInvalidSymlink(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{ // try reading victim/hello (../)
+			{
+				Name:     "dotdot",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (/../)
+			{
+				Name:     "slash-dotdot",
+				Typeflag: tar.TypeSymlink,
+				// Note the leading slash
+				Linkname: "/../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try writing victim/file
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim/file",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (symlink, symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "symlink",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (symlink, hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "hardlink",
+				Typeflag: tar.TypeLink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try removing victim directory (symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{ // try writing to victim/newdir/newfile with a symlink in the path
+			{
+				// this header needs to be before the next one, or else there is an error
+				Name:     "dir/loophole",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "dir/loophole/newdir/newfile",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("untar", "docker-TestUntarInvalidSymlink", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}
+
+func TestTempArchiveCloseMultipleTimes(t *testing.T) {
+	reader := ioutil.NopCloser(strings.NewReader("hello"))
+	tempArchive, err := NewTempArchive(reader, "")
+	buf := make([]byte, 10)
+	n, err := tempArchive.Read(buf)
+	if n != 5 {
+		t.Fatalf("Expected to read 5 bytes. Read %d instead", n)
+	}
+	for i := 0; i < 3; i++ {
+		if err = tempArchive.Close(); err != nil {
+			t.Fatalf("i=%d. Unexpected error closing temp archive: %v", i, err)
+		}
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/archive_unix.go

@@ -0,0 +1,39 @@
+// +build !windows
+
+package archive
+
+import (
+	"errors"
+	"syscall"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+)
+
+func setHeaderForSpecialDevice(hdr *tar.Header, ta *tarAppender, name string, stat interface{}) (nlink uint32, inode uint64, err error) {
+	s, ok := stat.(*syscall.Stat_t)
+
+	if !ok {
+		err = errors.New("cannot convert stat value to syscall.Stat_t")
+		return
+	}
+
+	nlink = uint32(s.Nlink)
+	inode = uint64(s.Ino)
+
+	// Currently go does not fil in the major/minors
+	if s.Mode&syscall.S_IFBLK == syscall.S_IFBLK ||
+		s.Mode&syscall.S_IFCHR == syscall.S_IFCHR {
+		hdr.Devmajor = int64(major(uint64(s.Rdev)))
+		hdr.Devminor = int64(minor(uint64(s.Rdev)))
+	}
+
+	return
+}
+
+func major(device uint64) uint64 {
+	return (device >> 8) & 0xfff
+}
+
+func minor(device uint64) uint64 {
+	return (device & 0xff) | ((device >> 12) & 0xfff00)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/archive_windows.go

@@ -0,0 +1,12 @@
+// +build windows
+
+package archive
+
+import (
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+)
+
+func setHeaderForSpecialDevice(hdr *tar.Header, ta *tarAppender, name string, stat interface{}) (nlink uint32, inode uint64, err error) {
+	// do nothing. no notion of Rdev, Inode, Nlink in stat on Windows
+	return
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/changes.go

@@ -0,0 +1,413 @@
+package archive
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+	"time"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+
+	log "github.com/Sirupsen/logrus"
+	"github.com/docker/docker/pkg/pools"
+	"github.com/docker/docker/pkg/system"
+)
+
+type ChangeType int
+
+const (
+	ChangeModify = iota
+	ChangeAdd
+	ChangeDelete
+)
+
+type Change struct {
+	Path string
+	Kind ChangeType
+}
+
+func (change *Change) String() string {
+	var kind string
+	switch change.Kind {
+	case ChangeModify:
+		kind = "C"
+	case ChangeAdd:
+		kind = "A"
+	case ChangeDelete:
+		kind = "D"
+	}
+	return fmt.Sprintf("%s %s", kind, change.Path)
+}
+
+// Gnu tar and the go tar writer don't have sub-second mtime
+// precision, which is problematic when we apply changes via tar
+// files, we handle this by comparing for exact times, *or* same
+// second count and either a or b having exactly 0 nanoseconds
+func sameFsTime(a, b time.Time) bool {
+	return a == b ||
+		(a.Unix() == b.Unix() &&
+			(a.Nanosecond() == 0 || b.Nanosecond() == 0))
+}
+
+func sameFsTimeSpec(a, b syscall.Timespec) bool {
+	return a.Sec == b.Sec &&
+		(a.Nsec == b.Nsec || a.Nsec == 0 || b.Nsec == 0)
+}
+
+// Changes walks the path rw and determines changes for the files in the path,
+// with respect to the parent layers
+func Changes(layers []string, rw string) ([]Change, error) {
+	var changes []Change
+	err := filepath.Walk(rw, func(path string, f os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		// Rebase path
+		path, err = filepath.Rel(rw, path)
+		if err != nil {
+			return err
+		}
+		path = filepath.Join("/", path)
+
+		// Skip root
+		if path == "/" {
+			return nil
+		}
+
+		// Skip AUFS metadata
+		if matched, err := filepath.Match("/.wh..wh.*", path); err != nil || matched {
+			return err
+		}
+
+		change := Change{
+			Path: path,
+		}
+
+		// Find out what kind of modification happened
+		file := filepath.Base(path)
+		// If there is a whiteout, then the file was removed
+		if strings.HasPrefix(file, ".wh.") {
+			originalFile := file[len(".wh."):]
+			change.Path = filepath.Join(filepath.Dir(path), originalFile)
+			change.Kind = ChangeDelete
+		} else {
+			// Otherwise, the file was added
+			change.Kind = ChangeAdd
+
+			// ...Unless it already existed in a top layer, in which case, it's a modification
+			for _, layer := range layers {
+				stat, err := os.Stat(filepath.Join(layer, path))
+				if err != nil && !os.IsNotExist(err) {
+					return err
+				}
+				if err == nil {
+					// The file existed in the top layer, so that's a modification
+
+					// However, if it's a directory, maybe it wasn't actually modified.
+					// If you modify /foo/bar/baz, then /foo will be part of the changed files only because it's the parent of bar
+					if stat.IsDir() && f.IsDir() {
+						if f.Size() == stat.Size() && f.Mode() == stat.Mode() && sameFsTime(f.ModTime(), stat.ModTime()) {
+							// Both directories are the same, don't record the change
+							return nil
+						}
+					}
+					change.Kind = ChangeModify
+					break
+				}
+			}
+		}
+
+		// Record change
+		changes = append(changes, change)
+		return nil
+	})
+	if err != nil && !os.IsNotExist(err) {
+		return nil, err
+	}
+	return changes, nil
+}
+
+type FileInfo struct {
+	parent     *FileInfo
+	name       string
+	stat       *system.Stat
+	children   map[string]*FileInfo
+	capability []byte
+	added      bool
+}
+
+func (root *FileInfo) LookUp(path string) *FileInfo {
+	parent := root
+	if path == "/" {
+		return root
+	}
+
+	pathElements := strings.Split(path, "/")
+	for _, elem := range pathElements {
+		if elem != "" {
+			child := parent.children[elem]
+			if child == nil {
+				return nil
+			}
+			parent = child
+		}
+	}
+	return parent
+}
+
+func (info *FileInfo) path() string {
+	if info.parent == nil {
+		return "/"
+	}
+	return filepath.Join(info.parent.path(), info.name)
+}
+
+func (info *FileInfo) isDir() bool {
+	return info.parent == nil || info.stat.Mode()&syscall.S_IFDIR == syscall.S_IFDIR
+}
+
+func (info *FileInfo) addChanges(oldInfo *FileInfo, changes *[]Change) {
+
+	sizeAtEntry := len(*changes)
+
+	if oldInfo == nil {
+		// add
+		change := Change{
+			Path: info.path(),
+			Kind: ChangeAdd,
+		}
+		*changes = append(*changes, change)
+		info.added = true
+	}
+
+	// We make a copy so we can modify it to detect additions
+	// also, we only recurse on the old dir if the new info is a directory
+	// otherwise any previous delete/change is considered recursive
+	oldChildren := make(map[string]*FileInfo)
+	if oldInfo != nil && info.isDir() {
+		for k, v := range oldInfo.children {
+			oldChildren[k] = v
+		}
+	}
+
+	for name, newChild := range info.children {
+		oldChild, _ := oldChildren[name]
+		if oldChild != nil {
+			// change?
+			oldStat := oldChild.stat
+			newStat := newChild.stat
+			// Note: We can't compare inode or ctime or blocksize here, because these change
+			// when copying a file into a container. However, that is not generally a problem
+			// because any content change will change mtime, and any status change should
+			// be visible when actually comparing the stat fields. The only time this
+			// breaks down is if some code intentionally hides a change by setting
+			// back mtime
+			if oldStat.Mode() != newStat.Mode() ||
+				oldStat.Uid() != newStat.Uid() ||
+				oldStat.Gid() != newStat.Gid() ||
+				oldStat.Rdev() != newStat.Rdev() ||
+				// Don't look at size for dirs, its not a good measure of change
+				(oldStat.Size() != newStat.Size() && oldStat.Mode()&syscall.S_IFDIR != syscall.S_IFDIR) ||
+				!sameFsTimeSpec(oldStat.Mtim(), newStat.Mtim()) ||
+				bytes.Compare(oldChild.capability, newChild.capability) != 0 {
+				change := Change{
+					Path: newChild.path(),
+					Kind: ChangeModify,
+				}
+				*changes = append(*changes, change)
+				newChild.added = true
+			}
+
+			// Remove from copy so we can detect deletions
+			delete(oldChildren, name)
+		}
+
+		newChild.addChanges(oldChild, changes)
+	}
+	for _, oldChild := range oldChildren {
+		// delete
+		change := Change{
+			Path: oldChild.path(),
+			Kind: ChangeDelete,
+		}
+		*changes = append(*changes, change)
+	}
+
+	// If there were changes inside this directory, we need to add it, even if the directory
+	// itself wasn't changed. This is needed to properly save and restore filesystem permissions.
+	if len(*changes) > sizeAtEntry && info.isDir() && !info.added && info.path() != "/" {
+		change := Change{
+			Path: info.path(),
+			Kind: ChangeModify,
+		}
+		// Let's insert the directory entry before the recently added entries located inside this dir
+		*changes = append(*changes, change) // just to resize the slice, will be overwritten
+		copy((*changes)[sizeAtEntry+1:], (*changes)[sizeAtEntry:])
+		(*changes)[sizeAtEntry] = change
+	}
+
+}
+
+func (info *FileInfo) Changes(oldInfo *FileInfo) []Change {
+	var changes []Change
+
+	info.addChanges(oldInfo, &changes)
+
+	return changes
+}
+
+func newRootFileInfo() *FileInfo {
+	root := &FileInfo{
+		name:     "/",
+		children: make(map[string]*FileInfo),
+	}
+	return root
+}
+
+func collectFileInfo(sourceDir string) (*FileInfo, error) {
+	root := newRootFileInfo()
+
+	err := filepath.Walk(sourceDir, func(path string, f os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		// Rebase path
+		relPath, err := filepath.Rel(sourceDir, path)
+		if err != nil {
+			return err
+		}
+		relPath = filepath.Join("/", relPath)
+
+		if relPath == "/" {
+			return nil
+		}
+
+		parent := root.LookUp(filepath.Dir(relPath))
+		if parent == nil {
+			return fmt.Errorf("collectFileInfo: Unexpectedly no parent for %s", relPath)
+		}
+
+		info := &FileInfo{
+			name:     filepath.Base(relPath),
+			children: make(map[string]*FileInfo),
+			parent:   parent,
+		}
+
+		s, err := system.Lstat(path)
+		if err != nil {
+			return err
+		}
+		info.stat = s
+
+		info.capability, _ = system.Lgetxattr(path, "security.capability")
+
+		parent.children[info.name] = info
+
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return root, nil
+}
+
+// ChangesDirs compares two directories and generates an array of Change objects describing the changes.
+// If oldDir is "", then all files in newDir will be Add-Changes.
+func ChangesDirs(newDir, oldDir string) ([]Change, error) {
+	var (
+		oldRoot, newRoot *FileInfo
+		err1, err2       error
+		errs             = make(chan error, 2)
+	)
+	go func() {
+		if oldDir != "" {
+			oldRoot, err1 = collectFileInfo(oldDir)
+		}
+		errs <- err1
+	}()
+	go func() {
+		newRoot, err2 = collectFileInfo(newDir)
+		errs <- err2
+	}()
+
+	// block until both routines have returned
+	for i := 0; i < 2; i++ {
+		if err := <-errs; err != nil {
+			return nil, err
+		}
+	}
+
+	return newRoot.Changes(oldRoot), nil
+}
+
+// ChangesSize calculates the size in bytes of the provided changes, based on newDir.
+func ChangesSize(newDir string, changes []Change) int64 {
+	var size int64
+	for _, change := range changes {
+		if change.Kind == ChangeModify || change.Kind == ChangeAdd {
+			file := filepath.Join(newDir, change.Path)
+			fileInfo, _ := os.Lstat(file)
+			if fileInfo != nil && !fileInfo.IsDir() {
+				size += fileInfo.Size()
+			}
+		}
+	}
+	return size
+}
+
+// ExportChanges produces an Archive from the provided changes, relative to dir.
+func ExportChanges(dir string, changes []Change) (Archive, error) {
+	reader, writer := io.Pipe()
+	go func() {
+		ta := &tarAppender{
+			TarWriter: tar.NewWriter(writer),
+			Buffer:    pools.BufioWriter32KPool.Get(nil),
+			SeenFiles: make(map[uint64]string),
+		}
+		// this buffer is needed for the duration of this piped stream
+		defer pools.BufioWriter32KPool.Put(ta.Buffer)
+
+		// In general we log errors here but ignore them because
+		// during e.g. a diff operation the container can continue
+		// mutating the filesystem and we can see transient errors
+		// from this
+		for _, change := range changes {
+			if change.Kind == ChangeDelete {
+				whiteOutDir := filepath.Dir(change.Path)
+				whiteOutBase := filepath.Base(change.Path)
+				whiteOut := filepath.Join(whiteOutDir, ".wh."+whiteOutBase)
+				timestamp := time.Now()
+				hdr := &tar.Header{
+					Name:       whiteOut[1:],
+					Size:       0,
+					ModTime:    timestamp,
+					AccessTime: timestamp,
+					ChangeTime: timestamp,
+				}
+				if err := ta.TarWriter.WriteHeader(hdr); err != nil {
+					log.Debugf("Can't write whiteout header: %s", err)
+				}
+			} else {
+				path := filepath.Join(dir, change.Path)
+				if err := ta.addTarFile(path, change.Path[1:]); err != nil {
+					log.Debugf("Can't add file %s to tar: %s", path, err)
+				}
+			}
+		}
+
+		// Make sure to check the error on Close.
+		if err := ta.TarWriter.Close(); err != nil {
+			log.Debugf("Can't close layer: %s", err)
+		}
+		if err := writer.Close(); err != nil {
+			log.Debugf("failed close Changes writer: %s", err)
+		}
+	}()
+	return reader, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/changes_test.go

@@ -0,0 +1,301 @@
+package archive
+
+import (
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path"
+	"sort"
+	"testing"
+	"time"
+)
+
+func max(x, y int) int {
+	if x >= y {
+		return x
+	}
+	return y
+}
+
+func copyDir(src, dst string) error {
+	cmd := exec.Command("cp", "-a", src, dst)
+	if err := cmd.Run(); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Helper to sort []Change by path
+type byPath struct{ changes []Change }
+
+func (b byPath) Less(i, j int) bool { return b.changes[i].Path < b.changes[j].Path }
+func (b byPath) Len() int           { return len(b.changes) }
+func (b byPath) Swap(i, j int)      { b.changes[i], b.changes[j] = b.changes[j], b.changes[i] }
+
+type FileType uint32
+
+const (
+	Regular FileType = iota
+	Dir
+	Symlink
+)
+
+type FileData struct {
+	filetype    FileType
+	path        string
+	contents    string
+	permissions os.FileMode
+}
+
+func createSampleDir(t *testing.T, root string) {
+	files := []FileData{
+		{Regular, "file1", "file1\n", 0600},
+		{Regular, "file2", "file2\n", 0666},
+		{Regular, "file3", "file3\n", 0404},
+		{Regular, "file4", "file4\n", 0600},
+		{Regular, "file5", "file5\n", 0600},
+		{Regular, "file6", "file6\n", 0600},
+		{Regular, "file7", "file7\n", 0600},
+		{Dir, "dir1", "", 0740},
+		{Regular, "dir1/file1-1", "file1-1\n", 01444},
+		{Regular, "dir1/file1-2", "file1-2\n", 0666},
+		{Dir, "dir2", "", 0700},
+		{Regular, "dir2/file2-1", "file2-1\n", 0666},
+		{Regular, "dir2/file2-2", "file2-2\n", 0666},
+		{Dir, "dir3", "", 0700},
+		{Regular, "dir3/file3-1", "file3-1\n", 0666},
+		{Regular, "dir3/file3-2", "file3-2\n", 0666},
+		{Dir, "dir4", "", 0700},
+		{Regular, "dir4/file3-1", "file4-1\n", 0666},
+		{Regular, "dir4/file3-2", "file4-2\n", 0666},
+		{Symlink, "symlink1", "target1", 0666},
+		{Symlink, "symlink2", "target2", 0666},
+	}
+
+	now := time.Now()
+	for _, info := range files {
+		p := path.Join(root, info.path)
+		if info.filetype == Dir {
+			if err := os.MkdirAll(p, info.permissions); err != nil {
+				t.Fatal(err)
+			}
+		} else if info.filetype == Regular {
+			if err := ioutil.WriteFile(p, []byte(info.contents), info.permissions); err != nil {
+				t.Fatal(err)
+			}
+		} else if info.filetype == Symlink {
+			if err := os.Symlink(info.contents, p); err != nil {
+				t.Fatal(err)
+			}
+		}
+
+		if info.filetype != Symlink {
+			// Set a consistent ctime, atime for all files and dirs
+			if err := os.Chtimes(p, now, now); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+}
+
+// Create an directory, copy it, make sure we report no changes between the two
+func TestChangesDirsEmpty(t *testing.T) {
+	src, err := ioutil.TempDir("", "docker-changes-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	createSampleDir(t, src)
+	dst := src + "-copy"
+	if err := copyDir(src, dst); err != nil {
+		t.Fatal(err)
+	}
+	changes, err := ChangesDirs(dst, src)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(changes) != 0 {
+		t.Fatalf("Reported changes for identical dirs: %v", changes)
+	}
+	os.RemoveAll(src)
+	os.RemoveAll(dst)
+}
+
+func mutateSampleDir(t *testing.T, root string) {
+	// Remove a regular file
+	if err := os.RemoveAll(path.Join(root, "file1")); err != nil {
+		t.Fatal(err)
+	}
+
+	// Remove a directory
+	if err := os.RemoveAll(path.Join(root, "dir1")); err != nil {
+		t.Fatal(err)
+	}
+
+	// Remove a symlink
+	if err := os.RemoveAll(path.Join(root, "symlink1")); err != nil {
+		t.Fatal(err)
+	}
+
+	// Rewrite a file
+	if err := ioutil.WriteFile(path.Join(root, "file2"), []byte("fileNN\n"), 0777); err != nil {
+		t.Fatal(err)
+	}
+
+	// Replace a file
+	if err := os.RemoveAll(path.Join(root, "file3")); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(path.Join(root, "file3"), []byte("fileMM\n"), 0404); err != nil {
+		t.Fatal(err)
+	}
+
+	// Touch file
+	if err := os.Chtimes(path.Join(root, "file4"), time.Now().Add(time.Second), time.Now().Add(time.Second)); err != nil {
+		t.Fatal(err)
+	}
+
+	// Replace file with dir
+	if err := os.RemoveAll(path.Join(root, "file5")); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.MkdirAll(path.Join(root, "file5"), 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	// Create new file
+	if err := ioutil.WriteFile(path.Join(root, "filenew"), []byte("filenew\n"), 0777); err != nil {
+		t.Fatal(err)
+	}
+
+	// Create new dir
+	if err := os.MkdirAll(path.Join(root, "dirnew"), 0766); err != nil {
+		t.Fatal(err)
+	}
+
+	// Create a new symlink
+	if err := os.Symlink("targetnew", path.Join(root, "symlinknew")); err != nil {
+		t.Fatal(err)
+	}
+
+	// Change a symlink
+	if err := os.RemoveAll(path.Join(root, "symlink2")); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Symlink("target2change", path.Join(root, "symlink2")); err != nil {
+		t.Fatal(err)
+	}
+
+	// Replace dir with file
+	if err := os.RemoveAll(path.Join(root, "dir2")); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(path.Join(root, "dir2"), []byte("dir2\n"), 0777); err != nil {
+		t.Fatal(err)
+	}
+
+	// Touch dir
+	if err := os.Chtimes(path.Join(root, "dir3"), time.Now().Add(time.Second), time.Now().Add(time.Second)); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestChangesDirsMutated(t *testing.T) {
+	src, err := ioutil.TempDir("", "docker-changes-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	createSampleDir(t, src)
+	dst := src + "-copy"
+	if err := copyDir(src, dst); err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(src)
+	defer os.RemoveAll(dst)
+
+	mutateSampleDir(t, dst)
+
+	changes, err := ChangesDirs(dst, src)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sort.Sort(byPath{changes})
+
+	expectedChanges := []Change{
+		{"/dir1", ChangeDelete},
+		{"/dir2", ChangeModify},
+		{"/dir3", ChangeModify},
+		{"/dirnew", ChangeAdd},
+		{"/file1", ChangeDelete},
+		{"/file2", ChangeModify},
+		{"/file3", ChangeModify},
+		{"/file4", ChangeModify},
+		{"/file5", ChangeModify},
+		{"/filenew", ChangeAdd},
+		{"/symlink1", ChangeDelete},
+		{"/symlink2", ChangeModify},
+		{"/symlinknew", ChangeAdd},
+	}
+
+	for i := 0; i < max(len(changes), len(expectedChanges)); i++ {
+		if i >= len(expectedChanges) {
+			t.Fatalf("unexpected change %s\n", changes[i].String())
+		}
+		if i >= len(changes) {
+			t.Fatalf("no change for expected change %s\n", expectedChanges[i].String())
+		}
+		if changes[i].Path == expectedChanges[i].Path {
+			if changes[i] != expectedChanges[i] {
+				t.Fatalf("Wrong change for %s, expected %s, got %s\n", changes[i].Path, changes[i].String(), expectedChanges[i].String())
+			}
+		} else if changes[i].Path < expectedChanges[i].Path {
+			t.Fatalf("unexpected change %s\n", changes[i].String())
+		} else {
+			t.Fatalf("no change for expected change %s != %s\n", expectedChanges[i].String(), changes[i].String())
+		}
+	}
+}
+
+func TestApplyLayer(t *testing.T) {
+	src, err := ioutil.TempDir("", "docker-changes-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	createSampleDir(t, src)
+	defer os.RemoveAll(src)
+	dst := src + "-copy"
+	if err := copyDir(src, dst); err != nil {
+		t.Fatal(err)
+	}
+	mutateSampleDir(t, dst)
+	defer os.RemoveAll(dst)
+
+	changes, err := ChangesDirs(dst, src)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	layer, err := ExportChanges(dst, changes)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	layerCopy, err := NewTempArchive(layer, "")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := ApplyLayer(src, layerCopy); err != nil {
+		t.Fatal(err)
+	}
+
+	changes2, err := ChangesDirs(src, dst)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(changes2) != 0 {
+		t.Fatalf("Unexpected differences after reapplying mutation: %v", changes2)
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/diff.go

@@ -0,0 +1,165 @@
+package archive
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+
+	"github.com/docker/docker/pkg/pools"
+	"github.com/docker/docker/pkg/system"
+)
+
+func UnpackLayer(dest string, layer ArchiveReader) error {
+	tr := tar.NewReader(layer)
+	trBuf := pools.BufioReader32KPool.Get(tr)
+	defer pools.BufioReader32KPool.Put(trBuf)
+
+	var dirs []*tar.Header
+
+	aufsTempdir := ""
+	aufsHardlinks := make(map[string]*tar.Header)
+
+	// Iterate through the files in the archive.
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			// end of tar archive
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		// Normalize name, for safety and for a simple is-root check
+		hdr.Name = filepath.Clean(hdr.Name)
+
+		if !strings.HasSuffix(hdr.Name, "/") {
+			// Not the root directory, ensure that the parent directory exists.
+			// This happened in some tests where an image had a tarfile without any
+			// parent directories.
+			parent := filepath.Dir(hdr.Name)
+			parentPath := filepath.Join(dest, parent)
+			if _, err := os.Lstat(parentPath); err != nil && os.IsNotExist(err) {
+				err = os.MkdirAll(parentPath, 0600)
+				if err != nil {
+					return err
+				}
+			}
+		}
+
+		// Skip AUFS metadata dirs
+		if strings.HasPrefix(hdr.Name, ".wh..wh.") {
+			// Regular files inside /.wh..wh.plnk can be used as hardlink targets
+			// We don't want this directory, but we need the files in them so that
+			// such hardlinks can be resolved.
+			if strings.HasPrefix(hdr.Name, ".wh..wh.plnk") && hdr.Typeflag == tar.TypeReg {
+				basename := filepath.Base(hdr.Name)
+				aufsHardlinks[basename] = hdr
+				if aufsTempdir == "" {
+					if aufsTempdir, err = ioutil.TempDir("", "dockerplnk"); err != nil {
+						return err
+					}
+					defer os.RemoveAll(aufsTempdir)
+				}
+				if err := createTarFile(filepath.Join(aufsTempdir, basename), dest, hdr, tr, true); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+
+		path := filepath.Join(dest, hdr.Name)
+		rel, err := filepath.Rel(dest, path)
+		if err != nil {
+			return err
+		}
+		if strings.HasPrefix(rel, "..") {
+			return breakoutError(fmt.Errorf("%q is outside of %q", hdr.Name, dest))
+		}
+		base := filepath.Base(path)
+
+		if strings.HasPrefix(base, ".wh.") {
+			originalBase := base[len(".wh."):]
+			originalPath := filepath.Join(filepath.Dir(path), originalBase)
+			if err := os.RemoveAll(originalPath); err != nil {
+				return err
+			}
+		} else {
+			// If path exits we almost always just want to remove and replace it.
+			// The only exception is when it is a directory *and* the file from
+			// the layer is also a directory. Then we want to merge them (i.e.
+			// just apply the metadata from the layer).
+			if fi, err := os.Lstat(path); err == nil {
+				if !(fi.IsDir() && hdr.Typeflag == tar.TypeDir) {
+					if err := os.RemoveAll(path); err != nil {
+						return err
+					}
+				}
+			}
+
+			trBuf.Reset(tr)
+			srcData := io.Reader(trBuf)
+			srcHdr := hdr
+
+			// Hard links into /.wh..wh.plnk don't work, as we don't extract that directory, so
+			// we manually retarget these into the temporary files we extracted them into
+			if hdr.Typeflag == tar.TypeLink && strings.HasPrefix(filepath.Clean(hdr.Linkname), ".wh..wh.plnk") {
+				linkBasename := filepath.Base(hdr.Linkname)
+				srcHdr = aufsHardlinks[linkBasename]
+				if srcHdr == nil {
+					return fmt.Errorf("Invalid aufs hardlink")
+				}
+				tmpFile, err := os.Open(filepath.Join(aufsTempdir, linkBasename))
+				if err != nil {
+					return err
+				}
+				defer tmpFile.Close()
+				srcData = tmpFile
+			}
+
+			if err := createTarFile(path, dest, srcHdr, srcData, true); err != nil {
+				return err
+			}
+
+			// Directory mtimes must be handled at the end to avoid further
+			// file creation in them to modify the directory mtime
+			if hdr.Typeflag == tar.TypeDir {
+				dirs = append(dirs, hdr)
+			}
+		}
+	}
+
+	for _, hdr := range dirs {
+		path := filepath.Join(dest, hdr.Name)
+		ts := []syscall.Timespec{timeToTimespec(hdr.AccessTime), timeToTimespec(hdr.ModTime)}
+		if err := syscall.UtimesNano(path, ts); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// ApplyLayer parses a diff in the standard layer format from `layer`, and
+// applies it to the directory `dest`.
+func ApplyLayer(dest string, layer ArchiveReader) error {
+	dest = filepath.Clean(dest)
+
+	// We need to be able to set any perms
+	oldmask, err := system.Umask(0)
+	if err != nil {
+		return err
+	}
+	defer system.Umask(oldmask) // ignore err, ErrNotSupportedPlatform
+
+	layer, err = DecompressStream(layer)
+	if err != nil {
+		return err
+	}
+	return UnpackLayer(dest, layer)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/diff_test.go

@@ -0,0 +1,191 @@
+package archive
+
+import (
+	"testing"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+)
+
+func TestApplyLayerInvalidFilenames(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{
+			{
+				Name:     "../victim/dotdot",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{
+			{
+				// Note the leading slash
+				Name:     "/../victim/slash-dotdot",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("applylayer", "docker-TestApplyLayerInvalidFilenames", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}
+
+func TestApplyLayerInvalidHardlink(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{ // try reading victim/hello (../)
+			{
+				Name:     "dotdot",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (/../)
+			{
+				Name:     "slash-dotdot",
+				Typeflag: tar.TypeLink,
+				// Note the leading slash
+				Linkname: "/../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try writing victim/file
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim/file",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (hardlink, symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "symlink",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // Try reading victim/hello (hardlink, hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "hardlink",
+				Typeflag: tar.TypeLink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // Try removing victim directory (hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeLink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("applylayer", "docker-TestApplyLayerInvalidHardlink", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}
+
+func TestApplyLayerInvalidSymlink(t *testing.T) {
+	for i, headers := range [][]*tar.Header{
+		{ // try reading victim/hello (../)
+			{
+				Name:     "dotdot",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (/../)
+			{
+				Name:     "slash-dotdot",
+				Typeflag: tar.TypeSymlink,
+				// Note the leading slash
+				Linkname: "/../victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try writing victim/file
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim/file",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (symlink, symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "symlink",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try reading victim/hello (symlink, hardlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "hardlink",
+				Typeflag: tar.TypeLink,
+				Linkname: "loophole-victim/hello",
+				Mode:     0644,
+			},
+		},
+		{ // try removing victim directory (symlink)
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeSymlink,
+				Linkname: "../victim",
+				Mode:     0755,
+			},
+			{
+				Name:     "loophole-victim",
+				Typeflag: tar.TypeReg,
+				Mode:     0644,
+			},
+		},
+	} {
+		if err := testBreakout("applylayer", "docker-TestApplyLayerInvalidSymlink", headers); err != nil {
+			t.Fatalf("i=%d. %v", i, err)
+		}
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/example_changes.go

@@ -0,0 +1,97 @@
+// +build ignore
+
+// Simple tool to create an archive stream from an old and new directory
+//
+// By default it will stream the comparison of two temporary directories with junk files
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker/pkg/archive"
+)
+
+var (
+	flDebug  = flag.Bool("D", false, "debugging output")
+	flNewDir = flag.String("newdir", "", "")
+	flOldDir = flag.String("olddir", "", "")
+	log      = logrus.New()
+)
+
+func main() {
+	flag.Usage = func() {
+		fmt.Println("Produce a tar from comparing two directory paths. By default a demo tar is created of around 200 files (including hardlinks)")
+		fmt.Printf("%s [OPTIONS]\n", os.Args[0])
+		flag.PrintDefaults()
+	}
+	flag.Parse()
+	log.Out = os.Stderr
+	if (len(os.Getenv("DEBUG")) > 0) || *flDebug {
+		logrus.SetLevel(logrus.DebugLevel)
+	}
+	var newDir, oldDir string
+
+	if len(*flNewDir) == 0 {
+		var err error
+		newDir, err = ioutil.TempDir("", "docker-test-newDir")
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer os.RemoveAll(newDir)
+		if _, err := prepareUntarSourceDirectory(100, newDir, true); err != nil {
+			log.Fatal(err)
+		}
+	} else {
+		newDir = *flNewDir
+	}
+
+	if len(*flOldDir) == 0 {
+		oldDir, err := ioutil.TempDir("", "docker-test-oldDir")
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer os.RemoveAll(oldDir)
+	} else {
+		oldDir = *flOldDir
+	}
+
+	changes, err := archive.ChangesDirs(newDir, oldDir)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	a, err := archive.ExportChanges(newDir, changes)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer a.Close()
+
+	i, err := io.Copy(os.Stdout, a)
+	if err != nil && err != io.EOF {
+		log.Fatal(err)
+	}
+	fmt.Fprintf(os.Stderr, "wrote archive of %d bytes", i)
+}
+
+func prepareUntarSourceDirectory(numberOfFiles int, targetPath string, makeLinks bool) (int, error) {
+	fileData := []byte("fooo")
+	for n := 0; n < numberOfFiles; n++ {
+		fileName := fmt.Sprintf("file-%d", n)
+		if err := ioutil.WriteFile(path.Join(targetPath, fileName), fileData, 0700); err != nil {
+			return 0, err
+		}
+		if makeLinks {
+			if err := os.Link(path.Join(targetPath, fileName), path.Join(targetPath, fileName+"-link")); err != nil {
+				return 0, err
+			}
+		}
+	}
+	totalSize := numberOfFiles * len(fileData)
+	return totalSize, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/time_linux.go

@@ -0,0 +1,16 @@
+package archive
+
+import (
+	"syscall"
+	"time"
+)
+
+func timeToTimespec(time time.Time) (ts syscall.Timespec) {
+	if time.IsZero() {
+		// Return UTIME_OMIT special value
+		ts.Sec = 0
+		ts.Nsec = ((1 << 30) - 2)
+		return
+	}
+	return syscall.NsecToTimespec(time.UnixNano())
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/time_unsupported.go

@@ -0,0 +1,16 @@
+// +build !linux
+
+package archive
+
+import (
+	"syscall"
+	"time"
+)
+
+func timeToTimespec(time time.Time) (ts syscall.Timespec) {
+	nsec := int64(0)
+	if !time.IsZero() {
+		nsec = time.UnixNano()
+	}
+	return syscall.NsecToTimespec(nsec)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/utils_test.go

@@ -0,0 +1,166 @@
+package archive
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+)
+
+var testUntarFns = map[string]func(string, io.Reader) error{
+	"untar": func(dest string, r io.Reader) error {
+		return Untar(r, dest, nil)
+	},
+	"applylayer": func(dest string, r io.Reader) error {
+		return ApplyLayer(dest, ArchiveReader(r))
+	},
+}
+
+// testBreakout is a helper function that, within the provided `tmpdir` directory,
+// creates a `victim` folder with a generated `hello` file in it.
+// `untar` extracts to a directory named `dest`, the tar file created from `headers`.
+//
+// Here are the tested scenarios:
+// - removed `victim` folder				(write)
+// - removed files from `victim` folder			(write)
+// - new files in `victim` folder			(write)
+// - modified files in `victim` folder			(write)
+// - file in `dest` with same content as `victim/hello` (read)
+//
+// When using testBreakout make sure you cover one of the scenarios listed above.
+func testBreakout(untarFn string, tmpdir string, headers []*tar.Header) error {
+	tmpdir, err := ioutil.TempDir("", tmpdir)
+	if err != nil {
+		return err
+	}
+	defer os.RemoveAll(tmpdir)
+
+	dest := filepath.Join(tmpdir, "dest")
+	if err := os.Mkdir(dest, 0755); err != nil {
+		return err
+	}
+
+	victim := filepath.Join(tmpdir, "victim")
+	if err := os.Mkdir(victim, 0755); err != nil {
+		return err
+	}
+	hello := filepath.Join(victim, "hello")
+	helloData, err := time.Now().MarshalText()
+	if err != nil {
+		return err
+	}
+	if err := ioutil.WriteFile(hello, helloData, 0644); err != nil {
+		return err
+	}
+	helloStat, err := os.Stat(hello)
+	if err != nil {
+		return err
+	}
+
+	reader, writer := io.Pipe()
+	go func() {
+		t := tar.NewWriter(writer)
+		for _, hdr := range headers {
+			t.WriteHeader(hdr)
+		}
+		t.Close()
+	}()
+
+	untar := testUntarFns[untarFn]
+	if untar == nil {
+		return fmt.Errorf("could not find untar function %q in testUntarFns", untarFn)
+	}
+	if err := untar(dest, reader); err != nil {
+		if _, ok := err.(breakoutError); !ok {
+			// If untar returns an error unrelated to an archive breakout,
+			// then consider this an unexpected error and abort.
+			return err
+		}
+		// Here, untar detected the breakout.
+		// Let's move on verifying that indeed there was no breakout.
+		fmt.Printf("breakoutError: %v\n", err)
+	}
+
+	// Check victim folder
+	f, err := os.Open(victim)
+	if err != nil {
+		// codepath taken if victim folder was removed
+		return fmt.Errorf("archive breakout: error reading %q: %v", victim, err)
+	}
+	defer f.Close()
+
+	// Check contents of victim folder
+	//
+	// We are only interested in getting 2 files from the victim folder, because if all is well
+	// we expect only one result, the `hello` file. If there is a second result, it cannot
+	// hold the same name `hello` and we assume that a new file got created in the victim folder.
+	// That is enough to detect an archive breakout.
+	names, err := f.Readdirnames(2)
+	if err != nil {
+		// codepath taken if victim is not a folder
+		return fmt.Errorf("archive breakout: error reading directory content of %q: %v", victim, err)
+	}
+	for _, name := range names {
+		if name != "hello" {
+			// codepath taken if new file was created in victim folder
+			return fmt.Errorf("archive breakout: new file %q", name)
+		}
+	}
+
+	// Check victim/hello
+	f, err = os.Open(hello)
+	if err != nil {
+		// codepath taken if read permissions were removed
+		return fmt.Errorf("archive breakout: could not lstat %q: %v", hello, err)
+	}
+	defer f.Close()
+	b, err := ioutil.ReadAll(f)
+	if err != nil {
+		return err
+	}
+	fi, err := f.Stat()
+	if err != nil {
+		return err
+	}
+	if helloStat.IsDir() != fi.IsDir() ||
+		// TODO: cannot check for fi.ModTime() change
+		helloStat.Mode() != fi.Mode() ||
+		helloStat.Size() != fi.Size() ||
+		!bytes.Equal(helloData, b) {
+		// codepath taken if hello has been modified
+		return fmt.Errorf("archive breakout: file %q has been modified. Contents: expected=%q, got=%q. FileInfo: expected=%#v, got=%#v.", hello, helloData, b, helloStat, fi)
+	}
+
+	// Check that nothing in dest/ has the same content as victim/hello.
+	// Since victim/hello was generated with time.Now(), it is safe to assume
+	// that any file whose content matches exactly victim/hello, managed somehow
+	// to access victim/hello.
+	return filepath.Walk(dest, func(path string, info os.FileInfo, err error) error {
+		if info.IsDir() {
+			if err != nil {
+				// skip directory if error
+				return filepath.SkipDir
+			}
+			// enter directory
+			return nil
+		}
+		if err != nil {
+			// skip file if error
+			return nil
+		}
+		b, err := ioutil.ReadFile(path)
+		if err != nil {
+			// Houston, we have a problem. Aborting (space)walk.
+			return err
+		}
+		if bytes.Equal(helloData, b) {
+			return fmt.Errorf("archive breakout: file %q has been accessed via %q", hello, path)
+		}
+		return nil
+	})
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/archive/wrap.go

@@ -0,0 +1,59 @@
+package archive
+
+import (
+	"bytes"
+	"github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
+	"io/ioutil"
+)
+
+// Generate generates a new archive from the content provided
+// as input.
+//
+// `files` is a sequence of path/content pairs. A new file is
+// added to the archive for each pair.
+// If the last pair is incomplete, the file is created with an
+// empty content. For example:
+//
+// Generate("foo.txt", "hello world", "emptyfile")
+//
+// The above call will return an archive with 2 files:
+//  * ./foo.txt with content "hello world"
+//  * ./empty with empty content
+//
+// FIXME: stream content instead of buffering
+// FIXME: specify permissions and other archive metadata
+func Generate(input ...string) (Archive, error) {
+	files := parseStringPairs(input...)
+	buf := new(bytes.Buffer)
+	tw := tar.NewWriter(buf)
+	for _, file := range files {
+		name, content := file[0], file[1]
+		hdr := &tar.Header{
+			Name: name,
+			Size: int64(len(content)),
+		}
+		if err := tw.WriteHeader(hdr); err != nil {
+			return nil, err
+		}
+		if _, err := tw.Write([]byte(content)); err != nil {
+			return nil, err
+		}
+	}
+	if err := tw.Close(); err != nil {
+		return nil, err
+	}
+	return ioutil.NopCloser(buf), nil
+}
+
+func parseStringPairs(input ...string) (output [][2]string) {
+	output = make([][2]string, 0, len(input)/2+1)
+	for i := 0; i < len(input); i += 2 {
+		var pair [2]string
+		pair[0] = input[i]
+		if i+1 < len(input) {
+			pair[1] = input[i+1]
+		}
+		output = append(output, pair)
+	}
+	return
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/fileutils/fileutils.go

@@ -0,0 +1,26 @@
+package fileutils
+
+import (
+	log "github.com/Sirupsen/logrus"
+	"path/filepath"
+)
+
+// Matches returns true if relFilePath matches any of the patterns
+func Matches(relFilePath string, patterns []string) (bool, error) {
+	for _, exclude := range patterns {
+		matched, err := filepath.Match(exclude, relFilePath)
+		if err != nil {
+			log.Errorf("Error matching: %s (pattern: %s)", relFilePath, exclude)
+			return false, err
+		}
+		if matched {
+			if filepath.Clean(relFilePath) == "." {
+				log.Errorf("Can't exclude whole path, excluding pattern: %s", exclude)
+				continue
+			}
+			log.Debugf("Skipping excluded path: %s", relFilePath)
+			return true, nil
+		}
+	}
+	return false, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/ioutils/readers.go

@@ -0,0 +1,114 @@
+package ioutils
+
+import (
+	"bytes"
+	"io"
+	"sync"
+)
+
+type readCloserWrapper struct {
+	io.Reader
+	closer func() error
+}
+
+func (r *readCloserWrapper) Close() error {
+	return r.closer()
+}
+
+func NewReadCloserWrapper(r io.Reader, closer func() error) io.ReadCloser {
+	return &readCloserWrapper{
+		Reader: r,
+		closer: closer,
+	}
+}
+
+type readerErrWrapper struct {
+	reader io.Reader
+	closer func()
+}
+
+func (r *readerErrWrapper) Read(p []byte) (int, error) {
+	n, err := r.reader.Read(p)
+	if err != nil {
+		r.closer()
+	}
+	return n, err
+}
+
+func NewReaderErrWrapper(r io.Reader, closer func()) io.Reader {
+	return &readerErrWrapper{
+		reader: r,
+		closer: closer,
+	}
+}
+
+type bufReader struct {
+	sync.Mutex
+	buf      *bytes.Buffer
+	reader   io.Reader
+	err      error
+	wait     sync.Cond
+	drainBuf []byte
+}
+
+func NewBufReader(r io.Reader) *bufReader {
+	reader := &bufReader{
+		buf:      &bytes.Buffer{},
+		drainBuf: make([]byte, 1024),
+		reader:   r,
+	}
+	reader.wait.L = &reader.Mutex
+	go reader.drain()
+	return reader
+}
+
+func NewBufReaderWithDrainbufAndBuffer(r io.Reader, drainBuffer []byte, buffer *bytes.Buffer) *bufReader {
+	reader := &bufReader{
+		buf:      buffer,
+		drainBuf: drainBuffer,
+		reader:   r,
+	}
+	reader.wait.L = &reader.Mutex
+	go reader.drain()
+	return reader
+}
+
+func (r *bufReader) drain() {
+	for {
+		n, err := r.reader.Read(r.drainBuf)
+		r.Lock()
+		if err != nil {
+			r.err = err
+		} else {
+			r.buf.Write(r.drainBuf[0:n])
+		}
+		r.wait.Signal()
+		r.Unlock()
+		if err != nil {
+			break
+		}
+	}
+}
+
+func (r *bufReader) Read(p []byte) (n int, err error) {
+	r.Lock()
+	defer r.Unlock()
+	for {
+		n, err = r.buf.Read(p)
+		if n > 0 {
+			return n, err
+		}
+		if r.err != nil {
+			return 0, r.err
+		}
+		r.wait.Wait()
+	}
+}
+
+func (r *bufReader) Close() error {
+	closer, ok := r.reader.(io.ReadCloser)
+	if !ok {
+		return nil
+	}
+	return closer.Close()
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/ioutils/readers_test.go

@@ -0,0 +1,34 @@
+package ioutils
+
+import (
+	"bytes"
+	"io"
+	"io/ioutil"
+	"testing"
+)
+
+func TestBufReader(t *testing.T) {
+	reader, writer := io.Pipe()
+	bufreader := NewBufReader(reader)
+
+	// Write everything down to a Pipe
+	// Usually, a pipe should block but because of the buffered reader,
+	// the writes will go through
+	done := make(chan bool)
+	go func() {
+		writer.Write([]byte("hello world"))
+		writer.Close()
+		done <- true
+	}()
+
+	// Drain the reader *after* everything has been written, just to verify
+	// it is indeed buffering
+	<-done
+	output, err := ioutil.ReadAll(bufreader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(output, []byte("hello world")) {
+		t.Error(string(output))
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/ioutils/writers.go

@@ -0,0 +1,39 @@
+package ioutils
+
+import "io"
+
+type NopWriter struct{}
+
+func (*NopWriter) Write(buf []byte) (int, error) {
+	return len(buf), nil
+}
+
+type nopWriteCloser struct {
+	io.Writer
+}
+
+func (w *nopWriteCloser) Close() error { return nil }
+
+func NopWriteCloser(w io.Writer) io.WriteCloser {
+	return &nopWriteCloser{w}
+}
+
+type NopFlusher struct{}
+
+func (f *NopFlusher) Flush() {}
+
+type writeCloserWrapper struct {
+	io.Writer
+	closer func() error
+}
+
+func (r *writeCloserWrapper) Close() error {
+	return r.closer()
+}
+
+func NewWriteCloserWrapper(r io.Writer, closer func() error) io.WriteCloser {
+	return &writeCloserWrapper{
+		Writer: r,
+		closer: closer,
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/pools/pools.go

@@ -0,0 +1,111 @@
+// +build go1.3
+
+// Package pools provides a collection of pools which provide various
+// data types with buffers. These can be used to lower the number of
+// memory allocations and reuse buffers.
+//
+// New pools should be added to this package to allow them to be
+// shared across packages.
+//
+// Utility functions which operate on pools should be added to this
+// package to allow them to be reused.
+package pools
+
+import (
+	"bufio"
+	"io"
+	"sync"
+
+	"github.com/docker/docker/pkg/ioutils"
+)
+
+var (
+	// Pool which returns bufio.Reader with a 32K buffer
+	BufioReader32KPool *BufioReaderPool
+	// Pool which returns bufio.Writer with a 32K buffer
+	BufioWriter32KPool *BufioWriterPool
+)
+
+const buffer32K = 32 * 1024
+
+type BufioReaderPool struct {
+	pool sync.Pool
+}
+
+func init() {
+	BufioReader32KPool = newBufioReaderPoolWithSize(buffer32K)
+	BufioWriter32KPool = newBufioWriterPoolWithSize(buffer32K)
+}
+
+// newBufioReaderPoolWithSize is unexported because new pools should be
+// added here to be shared where required.
+func newBufioReaderPoolWithSize(size int) *BufioReaderPool {
+	pool := sync.Pool{
+		New: func() interface{} { return bufio.NewReaderSize(nil, size) },
+	}
+	return &BufioReaderPool{pool: pool}
+}
+
+// Get returns a bufio.Reader which reads from r. The buffer size is that of the pool.
+func (bufPool *BufioReaderPool) Get(r io.Reader) *bufio.Reader {
+	buf := bufPool.pool.Get().(*bufio.Reader)
+	buf.Reset(r)
+	return buf
+}
+
+// Put puts the bufio.Reader back into the pool.
+func (bufPool *BufioReaderPool) Put(b *bufio.Reader) {
+	b.Reset(nil)
+	bufPool.pool.Put(b)
+}
+
+// NewReadCloserWrapper returns a wrapper which puts the bufio.Reader back
+// into the pool and closes the reader if it's an io.ReadCloser.
+func (bufPool *BufioReaderPool) NewReadCloserWrapper(buf *bufio.Reader, r io.Reader) io.ReadCloser {
+	return ioutils.NewReadCloserWrapper(r, func() error {
+		if readCloser, ok := r.(io.ReadCloser); ok {
+			readCloser.Close()
+		}
+		bufPool.Put(buf)
+		return nil
+	})
+}
+
+type BufioWriterPool struct {
+	pool sync.Pool
+}
+
+// newBufioWriterPoolWithSize is unexported because new pools should be
+// added here to be shared where required.
+func newBufioWriterPoolWithSize(size int) *BufioWriterPool {
+	pool := sync.Pool{
+		New: func() interface{} { return bufio.NewWriterSize(nil, size) },
+	}
+	return &BufioWriterPool{pool: pool}
+}
+
+// Get returns a bufio.Writer which writes to w. The buffer size is that of the pool.
+func (bufPool *BufioWriterPool) Get(w io.Writer) *bufio.Writer {
+	buf := bufPool.pool.Get().(*bufio.Writer)
+	buf.Reset(w)
+	return buf
+}
+
+// Put puts the bufio.Writer back into the pool.
+func (bufPool *BufioWriterPool) Put(b *bufio.Writer) {
+	b.Reset(nil)
+	bufPool.pool.Put(b)
+}
+
+// NewWriteCloserWrapper returns a wrapper which puts the bufio.Writer back
+// into the pool and closes the writer if it's an io.Writecloser.
+func (bufPool *BufioWriterPool) NewWriteCloserWrapper(buf *bufio.Writer, w io.Writer) io.WriteCloser {
+	return ioutils.NewWriteCloserWrapper(w, func() error {
+		buf.Flush()
+		if writeCloser, ok := w.(io.WriteCloser); ok {
+			writeCloser.Close()
+		}
+		bufPool.Put(buf)
+		return nil
+	})
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/pools/pools_nopool.go

@@ -0,0 +1,73 @@
+// +build !go1.3
+
+package pools
+
+import (
+	"bufio"
+	"io"
+
+	"github.com/docker/docker/pkg/ioutils"
+)
+
+var (
+	BufioReader32KPool *BufioReaderPool
+	BufioWriter32KPool *BufioWriterPool
+)
+
+const buffer32K = 32 * 1024
+
+type BufioReaderPool struct {
+	size int
+}
+
+func init() {
+	BufioReader32KPool = newBufioReaderPoolWithSize(buffer32K)
+	BufioWriter32KPool = newBufioWriterPoolWithSize(buffer32K)
+}
+
+func newBufioReaderPoolWithSize(size int) *BufioReaderPool {
+	return &BufioReaderPool{size: size}
+}
+
+func (bufPool *BufioReaderPool) Get(r io.Reader) *bufio.Reader {
+	return bufio.NewReaderSize(r, bufPool.size)
+}
+
+func (bufPool *BufioReaderPool) Put(b *bufio.Reader) {
+	b.Reset(nil)
+}
+
+func (bufPool *BufioReaderPool) NewReadCloserWrapper(buf *bufio.Reader, r io.Reader) io.ReadCloser {
+	return ioutils.NewReadCloserWrapper(r, func() error {
+		if readCloser, ok := r.(io.ReadCloser); ok {
+			return readCloser.Close()
+		}
+		return nil
+	})
+}
+
+type BufioWriterPool struct {
+	size int
+}
+
+func newBufioWriterPoolWithSize(size int) *BufioWriterPool {
+	return &BufioWriterPool{size: size}
+}
+
+func (bufPool *BufioWriterPool) Get(w io.Writer) *bufio.Writer {
+	return bufio.NewWriterSize(w, bufPool.size)
+}
+
+func (bufPool *BufioWriterPool) Put(b *bufio.Writer) {
+	b.Reset(nil)
+}
+
+func (bufPool *BufioWriterPool) NewWriteCloserWrapper(buf *bufio.Writer, w io.Writer) io.WriteCloser {
+	return ioutils.NewWriteCloserWrapper(w, func() error {
+		buf.Flush()
+		if writeCloser, ok := w.(io.WriteCloser); ok {
+			return writeCloser.Close()
+		}
+		return nil
+	})
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/promise/promise.go

@@ -0,0 +1,11 @@
+package promise
+
+// Go is a basic promise implementation: it wraps calls a function in a goroutine,
+// and returns a channel which will later return the function's return value.
+func Go(f func() error) chan error {
+	ch := make(chan error, 1)
+	go func() {
+		ch <- f()
+	}()
+	return ch
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/MAINTAINERS

@@ -0,0 +1,2 @@
+Michael Crosby <michael@crosbymichael.com> (@crosbymichael)
+Victor Vieux <vieux@docker.com> (@vieux)

Godeps/_workspace/src/github.com/docker/docker/pkg/system/errors.go

@@ -0,0 +1,9 @@
+package system
+
+import (
+	"errors"
+)
+
+var (
+	ErrNotSupportedPlatform = errors.New("platform and architecture is not supported")
+)

Godeps/_workspace/src/github.com/docker/docker/pkg/system/lstat.go

@@ -0,0 +1,16 @@
+// +build !windows
+
+package system
+
+import (
+	"syscall"
+)
+
+func Lstat(path string) (*Stat, error) {
+	s := &syscall.Stat_t{}
+	err := syscall.Lstat(path, s)
+	if err != nil {
+		return nil, err
+	}
+	return fromStatT(s)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/lstat_test.go

@@ -0,0 +1,27 @@
+package system
+
+import (
+	"os"
+	"testing"
+)
+
+func TestLstat(t *testing.T) {
+	file, invalid, _, dir := prepareFiles(t)
+	defer os.RemoveAll(dir)
+
+	statFile, err := Lstat(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if statFile == nil {
+		t.Fatal("returned empty stat for existing file")
+	}
+
+	statInvalid, err := Lstat(invalid)
+	if err == nil {
+		t.Fatal("did not return error for non-existing file")
+	}
+	if statInvalid != nil {
+		t.Fatal("returned non-nil stat for non-existing file")
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/lstat_windows.go

@@ -0,0 +1,8 @@
+// +build windows
+
+package system
+
+func Lstat(path string) (*Stat, error) {
+	// should not be called on cli code path
+	return nil, ErrNotSupportedPlatform
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/meminfo.go

@@ -0,0 +1,17 @@
+package system
+
+// MemInfo contains memory statistics of the host system.
+type MemInfo struct {
+	// Total usable RAM (i.e. physical RAM minus a few reserved bits and the
+	// kernel binary code).
+	MemTotal int64
+
+	// Amount of free memory.
+	MemFree int64
+
+	// Total amount of swap space available.
+	SwapTotal int64
+
+	// Amount of swap space that is currently unused.
+	SwapFree int64
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/meminfo_linux.go

@@ -0,0 +1,67 @@
+package system
+
+import (
+	"bufio"
+	"errors"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/docker/docker/pkg/units"
+)
+
+var (
+	ErrMalformed = errors.New("malformed file")
+)
+
+// Retrieve memory statistics of the host system and parse them into a MemInfo
+// type.
+func ReadMemInfo() (*MemInfo, error) {
+	file, err := os.Open("/proc/meminfo")
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+	return parseMemInfo(file)
+}
+
+func parseMemInfo(reader io.Reader) (*MemInfo, error) {
+	meminfo := &MemInfo{}
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		// Expected format: ["MemTotal:", "1234", "kB"]
+		parts := strings.Fields(scanner.Text())
+
+		// Sanity checks: Skip malformed entries.
+		if len(parts) < 3 || parts[2] != "kB" {
+			continue
+		}
+
+		// Convert to bytes.
+		size, err := strconv.Atoi(parts[1])
+		if err != nil {
+			continue
+		}
+		bytes := int64(size) * units.KiB
+
+		switch parts[0] {
+		case "MemTotal:":
+			meminfo.MemTotal = bytes
+		case "MemFree:":
+			meminfo.MemFree = bytes
+		case "SwapTotal:":
+			meminfo.SwapTotal = bytes
+		case "SwapFree:":
+			meminfo.SwapFree = bytes
+		}
+
+	}
+
+	// Handle errors that may have occurred during the reading of the file.
+	if err := scanner.Err(); err != nil {
+		return nil, err
+	}
+
+	return meminfo, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/meminfo_linux_test.go

@@ -0,0 +1,37 @@
+package system
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/docker/docker/pkg/units"
+)
+
+func TestMemInfo(t *testing.T) {
+	const input = `
+	MemTotal:      1 kB
+	MemFree:       2 kB
+	SwapTotal:     3 kB
+	SwapFree:      4 kB
+	Malformed1:
+	Malformed2:    1
+	Malformed3:    2 MB
+	Malformed4:    X kB
+	`
+	meminfo, err := parseMemInfo(strings.NewReader(input))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if meminfo.MemTotal != 1*units.KiB {
+		t.Fatalf("Unexpected MemTotal: %d", meminfo.MemTotal)
+	}
+	if meminfo.MemFree != 2*units.KiB {
+		t.Fatalf("Unexpected MemFree: %d", meminfo.MemFree)
+	}
+	if meminfo.SwapTotal != 3*units.KiB {
+		t.Fatalf("Unexpected SwapTotal: %d", meminfo.SwapTotal)
+	}
+	if meminfo.SwapFree != 4*units.KiB {
+		t.Fatalf("Unexpected SwapFree: %d", meminfo.SwapFree)
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/meminfo_unsupported.go

@@ -0,0 +1,7 @@
+// +build !linux
+
+package system
+
+func ReadMemInfo() (*MemInfo, error) {
+	return nil, ErrNotSupportedPlatform
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/mknod.go

@@ -0,0 +1,18 @@
+// +build !windows
+
+package system
+
+import (
+	"syscall"
+)
+
+func Mknod(path string, mode uint32, dev int) error {
+	return syscall.Mknod(path, mode, dev)
+}
+
+// Linux device nodes are a bit weird due to backwards compat with 16 bit device nodes.
+// They are, from low to high: the lower 8 bits of the minor, then 12 bits of the major,
+// then the top 12 bits of the minor
+func Mkdev(major int64, minor int64) uint32 {
+	return uint32(((minor & 0xfff00) << 12) | ((major & 0xfff) << 8) | (minor & 0xff))
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/mknod_windows.go

@@ -0,0 +1,12 @@
+// +build windows
+
+package system
+
+func Mknod(path string, mode uint32, dev int) error {
+	// should not be called on cli code path
+	return ErrNotSupportedPlatform
+}
+
+func Mkdev(major int64, minor int64) uint32 {
+	panic("Mkdev not implemented on windows, should not be called on cli code")
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/stat.go

@@ -0,0 +1,42 @@
+package system
+
+import (
+	"syscall"
+)
+
+type Stat struct {
+	mode uint32
+	uid  uint32
+	gid  uint32
+	rdev uint64
+	size int64
+	mtim syscall.Timespec
+}
+
+func (s Stat) Mode() uint32 {
+	return s.mode
+}
+
+func (s Stat) Uid() uint32 {
+	return s.uid
+}
+
+func (s Stat) Gid() uint32 {
+	return s.gid
+}
+
+func (s Stat) Rdev() uint64 {
+	return s.rdev
+}
+
+func (s Stat) Size() int64 {
+	return s.size
+}
+
+func (s Stat) Mtim() syscall.Timespec {
+	return s.mtim
+}
+
+func (s Stat) GetLastModification() syscall.Timespec {
+	return s.Mtim()
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/stat_linux.go

@@ -0,0 +1,14 @@
+package system
+
+import (
+	"syscall"
+)
+
+func fromStatT(s *syscall.Stat_t) (*Stat, error) {
+	return &Stat{size: s.Size,
+		mode: s.Mode,
+		uid:  s.Uid,
+		gid:  s.Gid,
+		rdev: s.Rdev,
+		mtim: s.Mtim}, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/stat_test.go

@@ -0,0 +1,36 @@
+package system
+
+import (
+	"os"
+	"syscall"
+	"testing"
+)
+
+func TestFromStatT(t *testing.T) {
+	file, _, _, dir := prepareFiles(t)
+	defer os.RemoveAll(dir)
+
+	stat := &syscall.Stat_t{}
+	err := syscall.Lstat(file, stat)
+
+	s, err := fromStatT(stat)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if stat.Mode != s.Mode() {
+		t.Fatal("got invalid mode")
+	}
+	if stat.Uid != s.Uid() {
+		t.Fatal("got invalid uid")
+	}
+	if stat.Gid != s.Gid() {
+		t.Fatal("got invalid gid")
+	}
+	if stat.Rdev != s.Rdev() {
+		t.Fatal("got invalid rdev")
+	}
+	if stat.Mtim != s.Mtim() {
+		t.Fatal("got invalid mtim")
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/stat_unsupported.go

@@ -0,0 +1,16 @@
+// +build !linux,!windows
+
+package system
+
+import (
+	"syscall"
+)
+
+func fromStatT(s *syscall.Stat_t) (*Stat, error) {
+	return &Stat{size: s.Size,
+		mode: uint32(s.Mode),
+		uid:  s.Uid,
+		gid:  s.Gid,
+		rdev: uint64(s.Rdev),
+		mtim: s.Mtimespec}, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/stat_windows.go

@@ -0,0 +1,12 @@
+// +build windows
+
+package system
+
+import (
+	"errors"
+	"syscall"
+)
+
+func fromStatT(s *syscall.Win32FileAttributeData) (*Stat, error) {
+	return nil, errors.New("fromStatT should not be called on windows path")
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/umask.go

@@ -0,0 +1,11 @@
+// +build !windows
+
+package system
+
+import (
+	"syscall"
+)
+
+func Umask(newmask int) (oldmask int, err error) {
+	return syscall.Umask(newmask), nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/umask_windows.go

@@ -0,0 +1,8 @@
+// +build windows
+
+package system
+
+func Umask(newmask int) (oldmask int, err error) {
+	// should not be called on cli code path
+	return 0, ErrNotSupportedPlatform
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/utimes_darwin.go

@@ -0,0 +1,11 @@
+package system
+
+import "syscall"
+
+func LUtimesNano(path string, ts []syscall.Timespec) error {
+	return ErrNotSupportedPlatform
+}
+
+func UtimesNano(path string, ts []syscall.Timespec) error {
+	return syscall.UtimesNano(path, ts)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/utimes_freebsd.go

@@ -0,0 +1,24 @@
+package system
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func LUtimesNano(path string, ts []syscall.Timespec) error {
+	var _path *byte
+	_path, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+
+	if _, _, err := syscall.Syscall(syscall.SYS_LUTIMES, uintptr(unsafe.Pointer(_path)), uintptr(unsafe.Pointer(&ts[0])), 0); err != 0 && err != syscall.ENOSYS {
+		return err
+	}
+
+	return nil
+}
+
+func UtimesNano(path string, ts []syscall.Timespec) error {
+	return syscall.UtimesNano(path, ts)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/utimes_linux.go

@@ -0,0 +1,28 @@
+package system
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+func LUtimesNano(path string, ts []syscall.Timespec) error {
+	// These are not currently available in syscall
+	AT_FDCWD := -100
+	AT_SYMLINK_NOFOLLOW := 0x100
+
+	var _path *byte
+	_path, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+
+	if _, _, err := syscall.Syscall6(syscall.SYS_UTIMENSAT, uintptr(AT_FDCWD), uintptr(unsafe.Pointer(_path)), uintptr(unsafe.Pointer(&ts[0])), uintptr(AT_SYMLINK_NOFOLLOW), 0, 0); err != 0 && err != syscall.ENOSYS {
+		return err
+	}
+
+	return nil
+}
+
+func UtimesNano(path string, ts []syscall.Timespec) error {
+	return syscall.UtimesNano(path, ts)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/utimes_test.go

@@ -0,0 +1,65 @@
+package system
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"syscall"
+	"testing"
+)
+
+func prepareFiles(t *testing.T) (string, string, string, string) {
+	dir, err := ioutil.TempDir("", "docker-system-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	file := filepath.Join(dir, "exist")
+	if err := ioutil.WriteFile(file, []byte("hello"), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	invalid := filepath.Join(dir, "doesnt-exist")
+
+	symlink := filepath.Join(dir, "symlink")
+	if err := os.Symlink(file, symlink); err != nil {
+		t.Fatal(err)
+	}
+
+	return file, invalid, symlink, dir
+}
+
+func TestLUtimesNano(t *testing.T) {
+	file, invalid, symlink, dir := prepareFiles(t)
+	defer os.RemoveAll(dir)
+
+	before, err := os.Stat(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ts := []syscall.Timespec{{0, 0}, {0, 0}}
+	if err := LUtimesNano(symlink, ts); err != nil {
+		t.Fatal(err)
+	}
+
+	symlinkInfo, err := os.Lstat(symlink)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if before.ModTime().Unix() == symlinkInfo.ModTime().Unix() {
+		t.Fatal("The modification time of the symlink should be different")
+	}
+
+	fileInfo, err := os.Stat(file)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if before.ModTime().Unix() != fileInfo.ModTime().Unix() {
+		t.Fatal("The modification time of the file should be same")
+	}
+
+	if err := LUtimesNano(invalid, ts); err == nil {
+		t.Fatal("Doesn't return an error on a non-existing file")
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/utimes_unsupported.go

@@ -0,0 +1,13 @@
+// +build !linux,!freebsd,!darwin
+
+package system
+
+import "syscall"
+
+func LUtimesNano(path string, ts []syscall.Timespec) error {
+	return ErrNotSupportedPlatform
+}
+
+func UtimesNano(path string, ts []syscall.Timespec) error {
+	return ErrNotSupportedPlatform
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/xattrs_linux.go

@@ -0,0 +1,59 @@
+package system
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+// Returns a nil slice and nil error if the xattr is not set
+func Lgetxattr(path string, attr string) ([]byte, error) {
+	pathBytes, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return nil, err
+	}
+	attrBytes, err := syscall.BytePtrFromString(attr)
+	if err != nil {
+		return nil, err
+	}
+
+	dest := make([]byte, 128)
+	destBytes := unsafe.Pointer(&dest[0])
+	sz, _, errno := syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0)
+	if errno == syscall.ENODATA {
+		return nil, nil
+	}
+	if errno == syscall.ERANGE {
+		dest = make([]byte, sz)
+		destBytes := unsafe.Pointer(&dest[0])
+		sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0)
+	}
+	if errno != 0 {
+		return nil, errno
+	}
+
+	return dest[:sz], nil
+}
+
+var _zero uintptr
+
+func Lsetxattr(path string, attr string, data []byte, flags int) error {
+	pathBytes, err := syscall.BytePtrFromString(path)
+	if err != nil {
+		return err
+	}
+	attrBytes, err := syscall.BytePtrFromString(attr)
+	if err != nil {
+		return err
+	}
+	var dataBytes unsafe.Pointer
+	if len(data) > 0 {
+		dataBytes = unsafe.Pointer(&data[0])
+	} else {
+		dataBytes = unsafe.Pointer(&_zero)
+	}
+	_, _, errno := syscall.Syscall6(syscall.SYS_LSETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(dataBytes), uintptr(len(data)), uintptr(flags), 0)
+	if errno != 0 {
+		return errno
+	}
+	return nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/system/xattrs_unsupported.go

@@ -0,0 +1,11 @@
+// +build !linux
+
+package system
+
+func Lgetxattr(path string, attr string) ([]byte, error) {
+	return nil, ErrNotSupportedPlatform
+}
+
+func Lsetxattr(path string, attr string, data []byte, flags int) error {
+	return ErrNotSupportedPlatform
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/units/MAINTAINERS

@@ -0,0 +1,2 @@
+Victor Vieux <vieux@docker.com> (@vieux)
+Jessie Frazelle <jess@docker.com> (@jfrazelle)

Godeps/_workspace/src/github.com/docker/docker/pkg/units/duration.go

@@ -0,0 +1,31 @@
+package units
+
+import (
+	"fmt"
+	"time"
+)
+
+// HumanDuration returns a human-readable approximation of a duration
+// (eg. "About a minute", "4 hours ago", etc.)
+func HumanDuration(d time.Duration) string {
+	if seconds := int(d.Seconds()); seconds < 1 {
+		return "Less than a second"
+	} else if seconds < 60 {
+		return fmt.Sprintf("%d seconds", seconds)
+	} else if minutes := int(d.Minutes()); minutes == 1 {
+		return "About a minute"
+	} else if minutes < 60 {
+		return fmt.Sprintf("%d minutes", minutes)
+	} else if hours := int(d.Hours()); hours == 1 {
+		return "About an hour"
+	} else if hours < 48 {
+		return fmt.Sprintf("%d hours", hours)
+	} else if hours < 24*7*2 {
+		return fmt.Sprintf("%d days", hours/24)
+	} else if hours < 24*30*3 {
+		return fmt.Sprintf("%d weeks", hours/24/7)
+	} else if hours < 24*365*2 {
+		return fmt.Sprintf("%d months", hours/24/30)
+	}
+	return fmt.Sprintf("%f years", d.Hours()/24/365)
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/units/duration_test.go

@@ -0,0 +1,46 @@
+package units
+
+import (
+	"testing"
+	"time"
+)
+
+func TestHumanDuration(t *testing.T) {
+	// Useful duration abstractions
+	day := 24 * time.Hour
+	week := 7 * day
+	month := 30 * day
+	year := 365 * day
+
+	assertEquals(t, "Less than a second", HumanDuration(450*time.Millisecond))
+	assertEquals(t, "47 seconds", HumanDuration(47*time.Second))
+	assertEquals(t, "About a minute", HumanDuration(1*time.Minute))
+	assertEquals(t, "3 minutes", HumanDuration(3*time.Minute))
+	assertEquals(t, "35 minutes", HumanDuration(35*time.Minute))
+	assertEquals(t, "35 minutes", HumanDuration(35*time.Minute+40*time.Second))
+	assertEquals(t, "About an hour", HumanDuration(1*time.Hour))
+	assertEquals(t, "About an hour", HumanDuration(1*time.Hour+45*time.Minute))
+	assertEquals(t, "3 hours", HumanDuration(3*time.Hour))
+	assertEquals(t, "3 hours", HumanDuration(3*time.Hour+59*time.Minute))
+	assertEquals(t, "4 hours", HumanDuration(3*time.Hour+60*time.Minute))
+	assertEquals(t, "24 hours", HumanDuration(24*time.Hour))
+	assertEquals(t, "36 hours", HumanDuration(1*day+12*time.Hour))
+	assertEquals(t, "2 days", HumanDuration(2*day))
+	assertEquals(t, "7 days", HumanDuration(7*day))
+	assertEquals(t, "13 days", HumanDuration(13*day+5*time.Hour))
+	assertEquals(t, "2 weeks", HumanDuration(2*week))
+	assertEquals(t, "2 weeks", HumanDuration(2*week+4*day))
+	assertEquals(t, "3 weeks", HumanDuration(3*week))
+	assertEquals(t, "4 weeks", HumanDuration(4*week))
+	assertEquals(t, "4 weeks", HumanDuration(4*week+3*day))
+	assertEquals(t, "4 weeks", HumanDuration(1*month))
+	assertEquals(t, "6 weeks", HumanDuration(1*month+2*week))
+	assertEquals(t, "8 weeks", HumanDuration(2*month))
+	assertEquals(t, "3 months", HumanDuration(3*month+1*week))
+	assertEquals(t, "5 months", HumanDuration(5*month+2*week))
+	assertEquals(t, "13 months", HumanDuration(13*month))
+	assertEquals(t, "23 months", HumanDuration(23*month))
+	assertEquals(t, "24 months", HumanDuration(24*month))
+	assertEquals(t, "2.010959 years", HumanDuration(24*month+2*week))
+	assertEquals(t, "3.164384 years", HumanDuration(3*year+2*month))
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/units/size.go

@@ -0,0 +1,91 @@
+package units
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// See: http://en.wikipedia.org/wiki/Binary_prefix
+const (
+	// Decimal
+
+	KB = 1000
+	MB = 1000 * KB
+	GB = 1000 * MB
+	TB = 1000 * GB
+	PB = 1000 * TB
+
+	// Binary
+
+	KiB = 1024
+	MiB = 1024 * KiB
+	GiB = 1024 * MiB
+	TiB = 1024 * GiB
+	PiB = 1024 * TiB
+)
+
+type unitMap map[string]int64
+
+var (
+	decimalMap = unitMap{"k": KB, "m": MB, "g": GB, "t": TB, "p": PB}
+	binaryMap  = unitMap{"k": KiB, "m": MiB, "g": GiB, "t": TiB, "p": PiB}
+	sizeRegex  = regexp.MustCompile(`^(\d+)([kKmMgGtTpP])?[bB]?$`)
+)
+
+var decimapAbbrs = []string{"B", "kB", "MB", "GB", "TB", "PB", "EB", "ZB", "YB"}
+var binaryAbbrs = []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB", "ZiB", "YiB"}
+
+// HumanSize returns a human-readable approximation of a size
+// using SI standard (eg. "44kB", "17MB")
+func HumanSize(size int64) string {
+	return intToString(float64(size), 1000.0, decimapAbbrs)
+}
+
+func BytesSize(size float64) string {
+	return intToString(size, 1024.0, binaryAbbrs)
+}
+
+func intToString(size, unit float64, _map []string) string {
+	i := 0
+	for size >= unit {
+		size = size / unit
+		i++
+	}
+	return fmt.Sprintf("%.4g %s", size, _map[i])
+}
+
+// FromHumanSize returns an integer from a human-readable specification of a
+// size using SI standard (eg. "44kB", "17MB")
+func FromHumanSize(size string) (int64, error) {
+	return parseSize(size, decimalMap)
+}
+
+// RAMInBytes parses a human-readable string representing an amount of RAM
+// in bytes, kibibytes, mebibytes, gibibytes, or tebibytes and
+// returns the number of bytes, or -1 if the string is unparseable.
+// Units are case-insensitive, and the 'b' suffix is optional.
+func RAMInBytes(size string) (int64, error) {
+	return parseSize(size, binaryMap)
+}
+
+// Parses the human-readable size string into the amount it represents
+func parseSize(sizeStr string, uMap unitMap) (int64, error) {
+	matches := sizeRegex.FindStringSubmatch(sizeStr)
+	if len(matches) != 3 {
+		return -1, fmt.Errorf("invalid size: '%s'", sizeStr)
+	}
+
+	size, err := strconv.ParseInt(matches[1], 10, 0)
+	if err != nil {
+		return -1, err
+	}
+
+	unitPrefix := strings.ToLower(matches[2])
+	if mul, ok := uMap[unitPrefix]; ok {
+		size *= mul
+	}
+
+	return size, nil
+}

Godeps/_workspace/src/github.com/docker/docker/pkg/units/size_test.go

@@ -0,0 +1,108 @@
+package units
+
+import (
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestBytesSize(t *testing.T) {
+	assertEquals(t, "1 KiB", BytesSize(1024))
+	assertEquals(t, "1 MiB", BytesSize(1024*1024))
+	assertEquals(t, "1 MiB", BytesSize(1048576))
+	assertEquals(t, "2 MiB", BytesSize(2*MiB))
+	assertEquals(t, "3.42 GiB", BytesSize(3.42*GiB))
+	assertEquals(t, "5.372 TiB", BytesSize(5.372*TiB))
+	assertEquals(t, "2.22 PiB", BytesSize(2.22*PiB))
+}
+
+func TestHumanSize(t *testing.T) {
+	assertEquals(t, "1 kB", HumanSize(1000))
+	assertEquals(t, "1.024 kB", HumanSize(1024))
+	assertEquals(t, "1 MB", HumanSize(1000000))
+	assertEquals(t, "1.049 MB", HumanSize(1048576))
+	assertEquals(t, "2 MB", HumanSize(2*MB))
+	assertEquals(t, "3.42 GB", HumanSize(int64(float64(3.42*GB))))
+	assertEquals(t, "5.372 TB", HumanSize(int64(float64(5.372*TB))))
+	assertEquals(t, "2.22 PB", HumanSize(int64(float64(2.22*PB))))
+}
+
+func TestFromHumanSize(t *testing.T) {
+	assertSuccessEquals(t, 32, FromHumanSize, "32")
+	assertSuccessEquals(t, 32, FromHumanSize, "32b")
+	assertSuccessEquals(t, 32, FromHumanSize, "32B")
+	assertSuccessEquals(t, 32*KB, FromHumanSize, "32k")
+	assertSuccessEquals(t, 32*KB, FromHumanSize, "32K")
+	assertSuccessEquals(t, 32*KB, FromHumanSize, "32kb")
+	assertSuccessEquals(t, 32*KB, FromHumanSize, "32Kb")
+	assertSuccessEquals(t, 32*MB, FromHumanSize, "32Mb")
+	assertSuccessEquals(t, 32*GB, FromHumanSize, "32Gb")
+	assertSuccessEquals(t, 32*TB, FromHumanSize, "32Tb")
+	assertSuccessEquals(t, 32*PB, FromHumanSize, "32Pb")
+
+	assertError(t, FromHumanSize, "")
+	assertError(t, FromHumanSize, "hello")
+	assertError(t, FromHumanSize, "-32")
+	assertError(t, FromHumanSize, "32.3")
+	assertError(t, FromHumanSize, " 32 ")
+	assertError(t, FromHumanSize, "32.3Kb")
+	assertError(t, FromHumanSize, "32 mb")
+	assertError(t, FromHumanSize, "32m b")
+	assertError(t, FromHumanSize, "32bm")
+}
+
+func TestRAMInBytes(t *testing.T) {
+	assertSuccessEquals(t, 32, RAMInBytes, "32")
+	assertSuccessEquals(t, 32, RAMInBytes, "32b")
+	assertSuccessEquals(t, 32, RAMInBytes, "32B")
+	assertSuccessEquals(t, 32*KiB, RAMInBytes, "32k")
+	assertSuccessEquals(t, 32*KiB, RAMInBytes, "32K")
+	assertSuccessEquals(t, 32*KiB, RAMInBytes, "32kb")
+	assertSuccessEquals(t, 32*KiB, RAMInBytes, "32Kb")
+	assertSuccessEquals(t, 32*MiB, RAMInBytes, "32Mb")
+	assertSuccessEquals(t, 32*GiB, RAMInBytes, "32Gb")
+	assertSuccessEquals(t, 32*TiB, RAMInBytes, "32Tb")
+	assertSuccessEquals(t, 32*PiB, RAMInBytes, "32Pb")
+	assertSuccessEquals(t, 32*PiB, RAMInBytes, "32PB")
+	assertSuccessEquals(t, 32*PiB, RAMInBytes, "32P")
+
+	assertError(t, RAMInBytes, "")
+	assertError(t, RAMInBytes, "hello")
+	assertError(t, RAMInBytes, "-32")
+	assertError(t, RAMInBytes, "32.3")
+	assertError(t, RAMInBytes, " 32 ")
+	assertError(t, RAMInBytes, "32.3Kb")
+	assertError(t, RAMInBytes, "32 mb")
+	assertError(t, RAMInBytes, "32m b")
+	assertError(t, RAMInBytes, "32bm")
+}
+
+func assertEquals(t *testing.T, expected, actual interface{}) {
+	if expected != actual {
+		t.Errorf("Expected '%v' but got '%v'", expected, actual)
+	}
+}
+
+// func that maps to the parse function signatures as testing abstraction
+type parseFn func(string) (int64, error)
+
+// Define 'String()' for pretty-print
+func (fn parseFn) String() string {
+	fnName := runtime.FuncForPC(reflect.ValueOf(fn).Pointer()).Name()
+	return fnName[strings.LastIndex(fnName, ".")+1:]
+}
+
+func assertSuccessEquals(t *testing.T, expected int64, fn parseFn, arg string) {
+	res, err := fn(arg)
+	if err != nil || res != expected {
+		t.Errorf("%s(\"%s\") -> expected '%d' but got '%d' with error '%v'", fn, arg, expected, res, err)
+	}
+}
+
+func assertError(t *testing.T, fn parseFn, arg string) {
+	res, err := fn(arg)
+	if err == nil && res != -1 {
+		t.Errorf("%s(\"%s\") -> expected error but got '%d'", fn, arg, res)
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/common.go

@@ -0,0 +1,305 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package tar implements access to tar archives.
+// It aims to cover most of the variations, including those produced
+// by GNU and BSD tars.
+//
+// References:
+//   http://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5
+//   http://www.gnu.org/software/tar/manual/html_node/Standard.html
+//   http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html
+package tar
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"os"
+	"path"
+	"time"
+)
+
+const (
+	blockSize = 512
+
+	// Types
+	TypeReg           = '0'    // regular file
+	TypeRegA          = '\x00' // regular file
+	TypeLink          = '1'    // hard link
+	TypeSymlink       = '2'    // symbolic link
+	TypeChar          = '3'    // character device node
+	TypeBlock         = '4'    // block device node
+	TypeDir           = '5'    // directory
+	TypeFifo          = '6'    // fifo node
+	TypeCont          = '7'    // reserved
+	TypeXHeader       = 'x'    // extended header
+	TypeXGlobalHeader = 'g'    // global extended header
+	TypeGNULongName   = 'L'    // Next file has a long name
+	TypeGNULongLink   = 'K'    // Next file symlinks to a file w/ a long name
+	TypeGNUSparse     = 'S'    // sparse file
+)
+
+// A Header represents a single header in a tar archive.
+// Some fields may not be populated.
+type Header struct {
+	Name       string    // name of header file entry
+	Mode       int64     // permission and mode bits
+	Uid        int       // user id of owner
+	Gid        int       // group id of owner
+	Size       int64     // length in bytes
+	ModTime    time.Time // modified time
+	Typeflag   byte      // type of header entry
+	Linkname   string    // target name of link
+	Uname      string    // user name of owner
+	Gname      string    // group name of owner
+	Devmajor   int64     // major number of character or block device
+	Devminor   int64     // minor number of character or block device
+	AccessTime time.Time // access time
+	ChangeTime time.Time // status change time
+	Xattrs     map[string]string
+}
+
+// File name constants from the tar spec.
+const (
+	fileNameSize       = 100 // Maximum number of bytes in a standard tar name.
+	fileNamePrefixSize = 155 // Maximum number of ustar extension bytes.
+)
+
+// FileInfo returns an os.FileInfo for the Header.
+func (h *Header) FileInfo() os.FileInfo {
+	return headerFileInfo{h}
+}
+
+// headerFileInfo implements os.FileInfo.
+type headerFileInfo struct {
+	h *Header
+}
+
+func (fi headerFileInfo) Size() int64        { return fi.h.Size }
+func (fi headerFileInfo) IsDir() bool        { return fi.Mode().IsDir() }
+func (fi headerFileInfo) ModTime() time.Time { return fi.h.ModTime }
+func (fi headerFileInfo) Sys() interface{}   { return fi.h }
+
+// Name returns the base name of the file.
+func (fi headerFileInfo) Name() string {
+	if fi.IsDir() {
+		return path.Base(path.Clean(fi.h.Name))
+	}
+	return path.Base(fi.h.Name)
+}
+
+// Mode returns the permission and mode bits for the headerFileInfo.
+func (fi headerFileInfo) Mode() (mode os.FileMode) {
+	// Set file permission bits.
+	mode = os.FileMode(fi.h.Mode).Perm()
+
+	// Set setuid, setgid and sticky bits.
+	if fi.h.Mode&c_ISUID != 0 {
+		// setuid
+		mode |= os.ModeSetuid
+	}
+	if fi.h.Mode&c_ISGID != 0 {
+		// setgid
+		mode |= os.ModeSetgid
+	}
+	if fi.h.Mode&c_ISVTX != 0 {
+		// sticky
+		mode |= os.ModeSticky
+	}
+
+	// Set file mode bits.
+	// clear perm, setuid, setgid and sticky bits.
+	m := os.FileMode(fi.h.Mode) &^ 07777
+	if m == c_ISDIR {
+		// directory
+		mode |= os.ModeDir
+	}
+	if m == c_ISFIFO {
+		// named pipe (FIFO)
+		mode |= os.ModeNamedPipe
+	}
+	if m == c_ISLNK {
+		// symbolic link
+		mode |= os.ModeSymlink
+	}
+	if m == c_ISBLK {
+		// device file
+		mode |= os.ModeDevice
+	}
+	if m == c_ISCHR {
+		// Unix character device
+		mode |= os.ModeDevice
+		mode |= os.ModeCharDevice
+	}
+	if m == c_ISSOCK {
+		// Unix domain socket
+		mode |= os.ModeSocket
+	}
+
+	switch fi.h.Typeflag {
+	case TypeLink, TypeSymlink:
+		// hard link, symbolic link
+		mode |= os.ModeSymlink
+	case TypeChar:
+		// character device node
+		mode |= os.ModeDevice
+		mode |= os.ModeCharDevice
+	case TypeBlock:
+		// block device node
+		mode |= os.ModeDevice
+	case TypeDir:
+		// directory
+		mode |= os.ModeDir
+	case TypeFifo:
+		// fifo node
+		mode |= os.ModeNamedPipe
+	}
+
+	return mode
+}
+
+// sysStat, if non-nil, populates h from system-dependent fields of fi.
+var sysStat func(fi os.FileInfo, h *Header) error
+
+// Mode constants from the tar spec.
+const (
+	c_ISUID  = 04000   // Set uid
+	c_ISGID  = 02000   // Set gid
+	c_ISVTX  = 01000   // Save text (sticky bit)
+	c_ISDIR  = 040000  // Directory
+	c_ISFIFO = 010000  // FIFO
+	c_ISREG  = 0100000 // Regular file
+	c_ISLNK  = 0120000 // Symbolic link
+	c_ISBLK  = 060000  // Block special file
+	c_ISCHR  = 020000  // Character special file
+	c_ISSOCK = 0140000 // Socket
+)
+
+// Keywords for the PAX Extended Header
+const (
+	paxAtime    = "atime"
+	paxCharset  = "charset"
+	paxComment  = "comment"
+	paxCtime    = "ctime" // please note that ctime is not a valid pax header.
+	paxGid      = "gid"
+	paxGname    = "gname"
+	paxLinkpath = "linkpath"
+	paxMtime    = "mtime"
+	paxPath     = "path"
+	paxSize     = "size"
+	paxUid      = "uid"
+	paxUname    = "uname"
+	paxXattr    = "SCHILY.xattr."
+	paxNone     = ""
+)
+
+// FileInfoHeader creates a partially-populated Header from fi.
+// If fi describes a symlink, FileInfoHeader records link as the link target.
+// If fi describes a directory, a slash is appended to the name.
+// Because os.FileInfo's Name method returns only the base name of
+// the file it describes, it may be necessary to modify the Name field
+// of the returned header to provide the full path name of the file.
+func FileInfoHeader(fi os.FileInfo, link string) (*Header, error) {
+	if fi == nil {
+		return nil, errors.New("tar: FileInfo is nil")
+	}
+	fm := fi.Mode()
+	h := &Header{
+		Name:    fi.Name(),
+		ModTime: fi.ModTime(),
+		Mode:    int64(fm.Perm()), // or'd with c_IS* constants later
+	}
+	switch {
+	case fm.IsRegular():
+		h.Mode |= c_ISREG
+		h.Typeflag = TypeReg
+		h.Size = fi.Size()
+	case fi.IsDir():
+		h.Typeflag = TypeDir
+		h.Mode |= c_ISDIR
+		h.Name += "/"
+	case fm&os.ModeSymlink != 0:
+		h.Typeflag = TypeSymlink
+		h.Mode |= c_ISLNK
+		h.Linkname = link
+	case fm&os.ModeDevice != 0:
+		if fm&os.ModeCharDevice != 0 {
+			h.Mode |= c_ISCHR
+			h.Typeflag = TypeChar
+		} else {
+			h.Mode |= c_ISBLK
+			h.Typeflag = TypeBlock
+		}
+	case fm&os.ModeNamedPipe != 0:
+		h.Typeflag = TypeFifo
+		h.Mode |= c_ISFIFO
+	case fm&os.ModeSocket != 0:
+		h.Mode |= c_ISSOCK
+	default:
+		return nil, fmt.Errorf("archive/tar: unknown file mode %v", fm)
+	}
+	if fm&os.ModeSetuid != 0 {
+		h.Mode |= c_ISUID
+	}
+	if fm&os.ModeSetgid != 0 {
+		h.Mode |= c_ISGID
+	}
+	if fm&os.ModeSticky != 0 {
+		h.Mode |= c_ISVTX
+	}
+	if sysStat != nil {
+		return h, sysStat(fi, h)
+	}
+	return h, nil
+}
+
+var zeroBlock = make([]byte, blockSize)
+
+// POSIX specifies a sum of the unsigned byte values, but the Sun tar uses signed byte values.
+// We compute and return both.
+func checksum(header []byte) (unsigned int64, signed int64) {
+	for i := 0; i < len(header); i++ {
+		if i == 148 {
+			// The chksum field (header[148:156]) is special: it should be treated as space bytes.
+			unsigned += ' ' * 8
+			signed += ' ' * 8
+			i += 7
+			continue
+		}
+		unsigned += int64(header[i])
+		signed += int64(int8(header[i]))
+	}
+	return
+}
+
+type slicer []byte
+
+func (sp *slicer) next(n int) (b []byte) {
+	s := *sp
+	b, *sp = s[0:n], s[n:]
+	return
+}
+
+func isASCII(s string) bool {
+	for _, c := range s {
+		if c >= 0x80 {
+			return false
+		}
+	}
+	return true
+}
+
+func toASCII(s string) string {
+	if isASCII(s) {
+		return s
+	}
+	var buf bytes.Buffer
+	for _, c := range s {
+		if c < 0x80 {
+			buf.WriteByte(byte(c))
+		}
+	}
+	return buf.String()
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/example_test.go

@@ -0,0 +1,79 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar_test
+
+import (
+	"archive/tar"
+	"bytes"
+	"fmt"
+	"io"
+	"log"
+	"os"
+)
+
+func Example() {
+	// Create a buffer to write our archive to.
+	buf := new(bytes.Buffer)
+
+	// Create a new tar archive.
+	tw := tar.NewWriter(buf)
+
+	// Add some files to the archive.
+	var files = []struct {
+		Name, Body string
+	}{
+		{"readme.txt", "This archive contains some text files."},
+		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
+		{"todo.txt", "Get animal handling licence."},
+	}
+	for _, file := range files {
+		hdr := &tar.Header{
+			Name: file.Name,
+			Size: int64(len(file.Body)),
+		}
+		if err := tw.WriteHeader(hdr); err != nil {
+			log.Fatalln(err)
+		}
+		if _, err := tw.Write([]byte(file.Body)); err != nil {
+			log.Fatalln(err)
+		}
+	}
+	// Make sure to check the error on Close.
+	if err := tw.Close(); err != nil {
+		log.Fatalln(err)
+	}
+
+	// Open the tar archive for reading.
+	r := bytes.NewReader(buf.Bytes())
+	tr := tar.NewReader(r)
+
+	// Iterate through the files in the archive.
+	for {
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			// end of tar archive
+			break
+		}
+		if err != nil {
+			log.Fatalln(err)
+		}
+		fmt.Printf("Contents of %s:\n", hdr.Name)
+		if _, err := io.Copy(os.Stdout, tr); err != nil {
+			log.Fatalln(err)
+		}
+		fmt.Println()
+	}
+
+	// Output:
+	// Contents of readme.txt:
+	// This archive contains some text files.
+	// Contents of gopher.txt:
+	// Gopher names:
+	// George
+	// Geoffrey
+	// Gonzo
+	// Contents of todo.txt:
+	// Get animal handling licence.
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/reader.go

@@ -0,0 +1,820 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar
+
+// TODO(dsymonds):
+//   - pax extensions
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	ErrHeader = errors.New("archive/tar: invalid tar header")
+)
+
+const maxNanoSecondIntSize = 9
+
+// A Reader provides sequential access to the contents of a tar archive.
+// A tar archive consists of a sequence of files.
+// The Next method advances to the next file in the archive (including the first),
+// and then it can be treated as an io.Reader to access the file's data.
+type Reader struct {
+	r       io.Reader
+	err     error
+	pad     int64           // amount of padding (ignored) after current file entry
+	curr    numBytesReader  // reader for current file entry
+	hdrBuff [blockSize]byte // buffer to use in readHeader
+}
+
+// A numBytesReader is an io.Reader with a numBytes method, returning the number
+// of bytes remaining in the underlying encoded data.
+type numBytesReader interface {
+	io.Reader
+	numBytes() int64
+}
+
+// A regFileReader is a numBytesReader for reading file data from a tar archive.
+type regFileReader struct {
+	r  io.Reader // underlying reader
+	nb int64     // number of unread bytes for current file entry
+}
+
+// A sparseFileReader is a numBytesReader for reading sparse file data from a tar archive.
+type sparseFileReader struct {
+	rfr *regFileReader // reads the sparse-encoded file data
+	sp  []sparseEntry  // the sparse map for the file
+	pos int64          // keeps track of file position
+	tot int64          // total size of the file
+}
+
+// Keywords for GNU sparse files in a PAX extended header
+const (
+	paxGNUSparseNumBlocks = "GNU.sparse.numblocks"
+	paxGNUSparseOffset    = "GNU.sparse.offset"
+	paxGNUSparseNumBytes  = "GNU.sparse.numbytes"
+	paxGNUSparseMap       = "GNU.sparse.map"
+	paxGNUSparseName      = "GNU.sparse.name"
+	paxGNUSparseMajor     = "GNU.sparse.major"
+	paxGNUSparseMinor     = "GNU.sparse.minor"
+	paxGNUSparseSize      = "GNU.sparse.size"
+	paxGNUSparseRealSize  = "GNU.sparse.realsize"
+)
+
+// Keywords for old GNU sparse headers
+const (
+	oldGNUSparseMainHeaderOffset               = 386
+	oldGNUSparseMainHeaderIsExtendedOffset     = 482
+	oldGNUSparseMainHeaderNumEntries           = 4
+	oldGNUSparseExtendedHeaderIsExtendedOffset = 504
+	oldGNUSparseExtendedHeaderNumEntries       = 21
+	oldGNUSparseOffsetSize                     = 12
+	oldGNUSparseNumBytesSize                   = 12
+)
+
+// NewReader creates a new Reader reading from r.
+func NewReader(r io.Reader) *Reader { return &Reader{r: r} }
+
+// Next advances to the next entry in the tar archive.
+func (tr *Reader) Next() (*Header, error) {
+	var hdr *Header
+	if tr.err == nil {
+		tr.skipUnread()
+	}
+	if tr.err != nil {
+		return hdr, tr.err
+	}
+	hdr = tr.readHeader()
+	if hdr == nil {
+		return hdr, tr.err
+	}
+	// Check for PAX/GNU header.
+	switch hdr.Typeflag {
+	case TypeXHeader:
+		//  PAX extended header
+		headers, err := parsePAX(tr)
+		if err != nil {
+			return nil, err
+		}
+		// We actually read the whole file,
+		// but this skips alignment padding
+		tr.skipUnread()
+		hdr = tr.readHeader()
+		mergePAX(hdr, headers)
+
+		// Check for a PAX format sparse file
+		sp, err := tr.checkForGNUSparsePAXHeaders(hdr, headers)
+		if err != nil {
+			tr.err = err
+			return nil, err
+		}
+		if sp != nil {
+			// Current file is a PAX format GNU sparse file.
+			// Set the current file reader to a sparse file reader.
+			tr.curr = &sparseFileReader{rfr: tr.curr.(*regFileReader), sp: sp, tot: hdr.Size}
+		}
+		return hdr, nil
+	case TypeGNULongName:
+		// We have a GNU long name header. Its contents are the real file name.
+		realname, err := ioutil.ReadAll(tr)
+		if err != nil {
+			return nil, err
+		}
+		hdr, err := tr.Next()
+		hdr.Name = cString(realname)
+		return hdr, err
+	case TypeGNULongLink:
+		// We have a GNU long link header.
+		realname, err := ioutil.ReadAll(tr)
+		if err != nil {
+			return nil, err
+		}
+		hdr, err := tr.Next()
+		hdr.Linkname = cString(realname)
+		return hdr, err
+	}
+	return hdr, tr.err
+}
+
+// checkForGNUSparsePAXHeaders checks the PAX headers for GNU sparse headers. If they are found, then
+// this function reads the sparse map and returns it. Unknown sparse formats are ignored, causing the file to
+// be treated as a regular file.
+func (tr *Reader) checkForGNUSparsePAXHeaders(hdr *Header, headers map[string]string) ([]sparseEntry, error) {
+	var sparseFormat string
+
+	// Check for sparse format indicators
+	major, majorOk := headers[paxGNUSparseMajor]
+	minor, minorOk := headers[paxGNUSparseMinor]
+	sparseName, sparseNameOk := headers[paxGNUSparseName]
+	_, sparseMapOk := headers[paxGNUSparseMap]
+	sparseSize, sparseSizeOk := headers[paxGNUSparseSize]
+	sparseRealSize, sparseRealSizeOk := headers[paxGNUSparseRealSize]
+
+	// Identify which, if any, sparse format applies from which PAX headers are set
+	if majorOk && minorOk {
+		sparseFormat = major + "." + minor
+	} else if sparseNameOk && sparseMapOk {
+		sparseFormat = "0.1"
+	} else if sparseSizeOk {
+		sparseFormat = "0.0"
+	} else {
+		// Not a PAX format GNU sparse file.
+		return nil, nil
+	}
+
+	// Check for unknown sparse format
+	if sparseFormat != "0.0" && sparseFormat != "0.1" && sparseFormat != "1.0" {
+		return nil, nil
+	}
+
+	// Update hdr from GNU sparse PAX headers
+	if sparseNameOk {
+		hdr.Name = sparseName
+	}
+	if sparseSizeOk {
+		realSize, err := strconv.ParseInt(sparseSize, 10, 0)
+		if err != nil {
+			return nil, ErrHeader
+		}
+		hdr.Size = realSize
+	} else if sparseRealSizeOk {
+		realSize, err := strconv.ParseInt(sparseRealSize, 10, 0)
+		if err != nil {
+			return nil, ErrHeader
+		}
+		hdr.Size = realSize
+	}
+
+	// Set up the sparse map, according to the particular sparse format in use
+	var sp []sparseEntry
+	var err error
+	switch sparseFormat {
+	case "0.0", "0.1":
+		sp, err = readGNUSparseMap0x1(headers)
+	case "1.0":
+		sp, err = readGNUSparseMap1x0(tr.curr)
+	}
+	return sp, err
+}
+
+// mergePAX merges well known headers according to PAX standard.
+// In general headers with the same name as those found
+// in the header struct overwrite those found in the header
+// struct with higher precision or longer values. Esp. useful
+// for name and linkname fields.
+func mergePAX(hdr *Header, headers map[string]string) error {
+	for k, v := range headers {
+		switch k {
+		case paxPath:
+			hdr.Name = v
+		case paxLinkpath:
+			hdr.Linkname = v
+		case paxGname:
+			hdr.Gname = v
+		case paxUname:
+			hdr.Uname = v
+		case paxUid:
+			uid, err := strconv.ParseInt(v, 10, 0)
+			if err != nil {
+				return err
+			}
+			hdr.Uid = int(uid)
+		case paxGid:
+			gid, err := strconv.ParseInt(v, 10, 0)
+			if err != nil {
+				return err
+			}
+			hdr.Gid = int(gid)
+		case paxAtime:
+			t, err := parsePAXTime(v)
+			if err != nil {
+				return err
+			}
+			hdr.AccessTime = t
+		case paxMtime:
+			t, err := parsePAXTime(v)
+			if err != nil {
+				return err
+			}
+			hdr.ModTime = t
+		case paxCtime:
+			t, err := parsePAXTime(v)
+			if err != nil {
+				return err
+			}
+			hdr.ChangeTime = t
+		case paxSize:
+			size, err := strconv.ParseInt(v, 10, 0)
+			if err != nil {
+				return err
+			}
+			hdr.Size = int64(size)
+		default:
+			if strings.HasPrefix(k, paxXattr) {
+				if hdr.Xattrs == nil {
+					hdr.Xattrs = make(map[string]string)
+				}
+				hdr.Xattrs[k[len(paxXattr):]] = v
+			}
+		}
+	}
+	return nil
+}
+
+// parsePAXTime takes a string of the form %d.%d as described in
+// the PAX specification.
+func parsePAXTime(t string) (time.Time, error) {
+	buf := []byte(t)
+	pos := bytes.IndexByte(buf, '.')
+	var seconds, nanoseconds int64
+	var err error
+	if pos == -1 {
+		seconds, err = strconv.ParseInt(t, 10, 0)
+		if err != nil {
+			return time.Time{}, err
+		}
+	} else {
+		seconds, err = strconv.ParseInt(string(buf[:pos]), 10, 0)
+		if err != nil {
+			return time.Time{}, err
+		}
+		nano_buf := string(buf[pos+1:])
+		// Pad as needed before converting to a decimal.
+		// For example .030 -> .030000000 -> 30000000 nanoseconds
+		if len(nano_buf) < maxNanoSecondIntSize {
+			// Right pad
+			nano_buf += strings.Repeat("0", maxNanoSecondIntSize-len(nano_buf))
+		} else if len(nano_buf) > maxNanoSecondIntSize {
+			// Right truncate
+			nano_buf = nano_buf[:maxNanoSecondIntSize]
+		}
+		nanoseconds, err = strconv.ParseInt(string(nano_buf), 10, 0)
+		if err != nil {
+			return time.Time{}, err
+		}
+	}
+	ts := time.Unix(seconds, nanoseconds)
+	return ts, nil
+}
+
+// parsePAX parses PAX headers.
+// If an extended header (type 'x') is invalid, ErrHeader is returned
+func parsePAX(r io.Reader) (map[string]string, error) {
+	buf, err := ioutil.ReadAll(r)
+	if err != nil {
+		return nil, err
+	}
+
+	// For GNU PAX sparse format 0.0 support.
+	// This function transforms the sparse format 0.0 headers into sparse format 0.1 headers.
+	var sparseMap bytes.Buffer
+
+	headers := make(map[string]string)
+	// Each record is constructed as
+	//     "%d %s=%s\n", length, keyword, value
+	for len(buf) > 0 {
+		// or the header was empty to start with.
+		var sp int
+		// The size field ends at the first space.
+		sp = bytes.IndexByte(buf, ' ')
+		if sp == -1 {
+			return nil, ErrHeader
+		}
+		// Parse the first token as a decimal integer.
+		n, err := strconv.ParseInt(string(buf[:sp]), 10, 0)
+		if err != nil {
+			return nil, ErrHeader
+		}
+		// Extract everything between the decimal and the n -1 on the
+		// beginning to eat the ' ', -1 on the end to skip the newline.
+		var record []byte
+		record, buf = buf[sp+1:n-1], buf[n:]
+		// The first equals is guaranteed to mark the end of the key.
+		// Everything else is value.
+		eq := bytes.IndexByte(record, '=')
+		if eq == -1 {
+			return nil, ErrHeader
+		}
+		key, value := record[:eq], record[eq+1:]
+
+		keyStr := string(key)
+		if keyStr == paxGNUSparseOffset || keyStr == paxGNUSparseNumBytes {
+			// GNU sparse format 0.0 special key. Write to sparseMap instead of using the headers map.
+			sparseMap.Write(value)
+			sparseMap.Write([]byte{','})
+		} else {
+			// Normal key. Set the value in the headers map.
+			headers[keyStr] = string(value)
+		}
+	}
+	if sparseMap.Len() != 0 {
+		// Add sparse info to headers, chopping off the extra comma
+		sparseMap.Truncate(sparseMap.Len() - 1)
+		headers[paxGNUSparseMap] = sparseMap.String()
+	}
+	return headers, nil
+}
+
+// cString parses bytes as a NUL-terminated C-style string.
+// If a NUL byte is not found then the whole slice is returned as a string.
+func cString(b []byte) string {
+	n := 0
+	for n < len(b) && b[n] != 0 {
+		n++
+	}
+	return string(b[0:n])
+}
+
+func (tr *Reader) octal(b []byte) int64 {
+	// Check for binary format first.
+	if len(b) > 0 && b[0]&0x80 != 0 {
+		var x int64
+		for i, c := range b {
+			if i == 0 {
+				c &= 0x7f // ignore signal bit in first byte
+			}
+			x = x<<8 | int64(c)
+		}
+		return x
+	}
+
+	// Because unused fields are filled with NULs, we need
+	// to skip leading NULs. Fields may also be padded with
+	// spaces or NULs.
+	// So we remove leading and trailing NULs and spaces to
+	// be sure.
+	b = bytes.Trim(b, " \x00")
+
+	if len(b) == 0 {
+		return 0
+	}
+	x, err := strconv.ParseUint(cString(b), 8, 64)
+	if err != nil {
+		tr.err = err
+	}
+	return int64(x)
+}
+
+// skipUnread skips any unread bytes in the existing file entry, as well as any alignment padding.
+func (tr *Reader) skipUnread() {
+	nr := tr.numBytes() + tr.pad // number of bytes to skip
+	tr.curr, tr.pad = nil, 0
+	if sr, ok := tr.r.(io.Seeker); ok {
+		if _, err := sr.Seek(nr, os.SEEK_CUR); err == nil {
+			return
+		}
+	}
+	_, tr.err = io.CopyN(ioutil.Discard, tr.r, nr)
+}
+
+func (tr *Reader) verifyChecksum(header []byte) bool {
+	if tr.err != nil {
+		return false
+	}
+
+	given := tr.octal(header[148:156])
+	unsigned, signed := checksum(header)
+	return given == unsigned || given == signed
+}
+
+func (tr *Reader) readHeader() *Header {
+	header := tr.hdrBuff[:]
+	copy(header, zeroBlock)
+
+	if _, tr.err = io.ReadFull(tr.r, header); tr.err != nil {
+		return nil
+	}
+
+	// Two blocks of zero bytes marks the end of the archive.
+	if bytes.Equal(header, zeroBlock[0:blockSize]) {
+		if _, tr.err = io.ReadFull(tr.r, header); tr.err != nil {
+			return nil
+		}
+		if bytes.Equal(header, zeroBlock[0:blockSize]) {
+			tr.err = io.EOF
+		} else {
+			tr.err = ErrHeader // zero block and then non-zero block
+		}
+		return nil
+	}
+
+	if !tr.verifyChecksum(header) {
+		tr.err = ErrHeader
+		return nil
+	}
+
+	// Unpack
+	hdr := new(Header)
+	s := slicer(header)
+
+	hdr.Name = cString(s.next(100))
+	hdr.Mode = tr.octal(s.next(8))
+	hdr.Uid = int(tr.octal(s.next(8)))
+	hdr.Gid = int(tr.octal(s.next(8)))
+	hdr.Size = tr.octal(s.next(12))
+	hdr.ModTime = time.Unix(tr.octal(s.next(12)), 0)
+	s.next(8) // chksum
+	hdr.Typeflag = s.next(1)[0]
+	hdr.Linkname = cString(s.next(100))
+
+	// The remainder of the header depends on the value of magic.
+	// The original (v7) version of tar had no explicit magic field,
+	// so its magic bytes, like the rest of the block, are NULs.
+	magic := string(s.next(8)) // contains version field as well.
+	var format string
+	switch {
+	case magic[:6] == "ustar\x00": // POSIX tar (1003.1-1988)
+		if string(header[508:512]) == "tar\x00" {
+			format = "star"
+		} else {
+			format = "posix"
+		}
+	case magic == "ustar  \x00": // old GNU tar
+		format = "gnu"
+	}
+
+	switch format {
+	case "posix", "gnu", "star":
+		hdr.Uname = cString(s.next(32))
+		hdr.Gname = cString(s.next(32))
+		devmajor := s.next(8)
+		devminor := s.next(8)
+		if hdr.Typeflag == TypeChar || hdr.Typeflag == TypeBlock {
+			hdr.Devmajor = tr.octal(devmajor)
+			hdr.Devminor = tr.octal(devminor)
+		}
+		var prefix string
+		switch format {
+		case "posix", "gnu":
+			prefix = cString(s.next(155))
+		case "star":
+			prefix = cString(s.next(131))
+			hdr.AccessTime = time.Unix(tr.octal(s.next(12)), 0)
+			hdr.ChangeTime = time.Unix(tr.octal(s.next(12)), 0)
+		}
+		if len(prefix) > 0 {
+			hdr.Name = prefix + "/" + hdr.Name
+		}
+	}
+
+	if tr.err != nil {
+		tr.err = ErrHeader
+		return nil
+	}
+
+	// Maximum value of hdr.Size is 64 GB (12 octal digits),
+	// so there's no risk of int64 overflowing.
+	nb := int64(hdr.Size)
+	tr.pad = -nb & (blockSize - 1) // blockSize is a power of two
+
+	// Set the current file reader.
+	tr.curr = &regFileReader{r: tr.r, nb: nb}
+
+	// Check for old GNU sparse format entry.
+	if hdr.Typeflag == TypeGNUSparse {
+		// Get the real size of the file.
+		hdr.Size = tr.octal(header[483:495])
+
+		// Read the sparse map.
+		sp := tr.readOldGNUSparseMap(header)
+		if tr.err != nil {
+			return nil
+		}
+		// Current file is a GNU sparse file. Update the current file reader.
+		tr.curr = &sparseFileReader{rfr: tr.curr.(*regFileReader), sp: sp, tot: hdr.Size}
+	}
+
+	return hdr
+}
+
+// A sparseEntry holds a single entry in a sparse file's sparse map.
+// A sparse entry indicates the offset and size in a sparse file of a
+// block of data.
+type sparseEntry struct {
+	offset   int64
+	numBytes int64
+}
+
+// readOldGNUSparseMap reads the sparse map as stored in the old GNU sparse format.
+// The sparse map is stored in the tar header if it's small enough. If it's larger than four entries,
+// then one or more extension headers are used to store the rest of the sparse map.
+func (tr *Reader) readOldGNUSparseMap(header []byte) []sparseEntry {
+	isExtended := header[oldGNUSparseMainHeaderIsExtendedOffset] != 0
+	spCap := oldGNUSparseMainHeaderNumEntries
+	if isExtended {
+		spCap += oldGNUSparseExtendedHeaderNumEntries
+	}
+	sp := make([]sparseEntry, 0, spCap)
+	s := slicer(header[oldGNUSparseMainHeaderOffset:])
+
+	// Read the four entries from the main tar header
+	for i := 0; i < oldGNUSparseMainHeaderNumEntries; i++ {
+		offset := tr.octal(s.next(oldGNUSparseOffsetSize))
+		numBytes := tr.octal(s.next(oldGNUSparseNumBytesSize))
+		if tr.err != nil {
+			tr.err = ErrHeader
+			return nil
+		}
+		if offset == 0 && numBytes == 0 {
+			break
+		}
+		sp = append(sp, sparseEntry{offset: offset, numBytes: numBytes})
+	}
+
+	for isExtended {
+		// There are more entries. Read an extension header and parse its entries.
+		sparseHeader := make([]byte, blockSize)
+		if _, tr.err = io.ReadFull(tr.r, sparseHeader); tr.err != nil {
+			return nil
+		}
+		isExtended = sparseHeader[oldGNUSparseExtendedHeaderIsExtendedOffset] != 0
+		s = slicer(sparseHeader)
+		for i := 0; i < oldGNUSparseExtendedHeaderNumEntries; i++ {
+			offset := tr.octal(s.next(oldGNUSparseOffsetSize))
+			numBytes := tr.octal(s.next(oldGNUSparseNumBytesSize))
+			if tr.err != nil {
+				tr.err = ErrHeader
+				return nil
+			}
+			if offset == 0 && numBytes == 0 {
+				break
+			}
+			sp = append(sp, sparseEntry{offset: offset, numBytes: numBytes})
+		}
+	}
+	return sp
+}
+
+// readGNUSparseMap1x0 reads the sparse map as stored in GNU's PAX sparse format version 1.0.
+// The sparse map is stored just before the file data and padded out to the nearest block boundary.
+func readGNUSparseMap1x0(r io.Reader) ([]sparseEntry, error) {
+	buf := make([]byte, 2*blockSize)
+	sparseHeader := buf[:blockSize]
+
+	// readDecimal is a helper function to read a decimal integer from the sparse map
+	// while making sure to read from the file in blocks of size blockSize
+	readDecimal := func() (int64, error) {
+		// Look for newline
+		nl := bytes.IndexByte(sparseHeader, '\n')
+		if nl == -1 {
+			if len(sparseHeader) >= blockSize {
+				// This is an error
+				return 0, ErrHeader
+			}
+			oldLen := len(sparseHeader)
+			newLen := oldLen + blockSize
+			if cap(sparseHeader) < newLen {
+				// There's more header, but we need to make room for the next block
+				copy(buf, sparseHeader)
+				sparseHeader = buf[:newLen]
+			} else {
+				// There's more header, and we can just reslice
+				sparseHeader = sparseHeader[:newLen]
+			}
+
+			// Now that sparseHeader is large enough, read next block
+			if _, err := io.ReadFull(r, sparseHeader[oldLen:newLen]); err != nil {
+				return 0, err
+			}
+
+			// Look for a newline in the new data
+			nl = bytes.IndexByte(sparseHeader[oldLen:newLen], '\n')
+			if nl == -1 {
+				// This is an error
+				return 0, ErrHeader
+			}
+			nl += oldLen // We want the position from the beginning
+		}
+		// Now that we've found a newline, read a number
+		n, err := strconv.ParseInt(string(sparseHeader[:nl]), 10, 0)
+		if err != nil {
+			return 0, ErrHeader
+		}
+
+		// Update sparseHeader to consume this number
+		sparseHeader = sparseHeader[nl+1:]
+		return n, nil
+	}
+
+	// Read the first block
+	if _, err := io.ReadFull(r, sparseHeader); err != nil {
+		return nil, err
+	}
+
+	// The first line contains the number of entries
+	numEntries, err := readDecimal()
+	if err != nil {
+		return nil, err
+	}
+
+	// Read all the entries
+	sp := make([]sparseEntry, 0, numEntries)
+	for i := int64(0); i < numEntries; i++ {
+		// Read the offset
+		offset, err := readDecimal()
+		if err != nil {
+			return nil, err
+		}
+		// Read numBytes
+		numBytes, err := readDecimal()
+		if err != nil {
+			return nil, err
+		}
+
+		sp = append(sp, sparseEntry{offset: offset, numBytes: numBytes})
+	}
+
+	return sp, nil
+}
+
+// readGNUSparseMap0x1 reads the sparse map as stored in GNU's PAX sparse format version 0.1.
+// The sparse map is stored in the PAX headers.
+func readGNUSparseMap0x1(headers map[string]string) ([]sparseEntry, error) {
+	// Get number of entries
+	numEntriesStr, ok := headers[paxGNUSparseNumBlocks]
+	if !ok {
+		return nil, ErrHeader
+	}
+	numEntries, err := strconv.ParseInt(numEntriesStr, 10, 0)
+	if err != nil {
+		return nil, ErrHeader
+	}
+
+	sparseMap := strings.Split(headers[paxGNUSparseMap], ",")
+
+	// There should be two numbers in sparseMap for each entry
+	if int64(len(sparseMap)) != 2*numEntries {
+		return nil, ErrHeader
+	}
+
+	// Loop through the entries in the sparse map
+	sp := make([]sparseEntry, 0, numEntries)
+	for i := int64(0); i < numEntries; i++ {
+		offset, err := strconv.ParseInt(sparseMap[2*i], 10, 0)
+		if err != nil {
+			return nil, ErrHeader
+		}
+		numBytes, err := strconv.ParseInt(sparseMap[2*i+1], 10, 0)
+		if err != nil {
+			return nil, ErrHeader
+		}
+		sp = append(sp, sparseEntry{offset: offset, numBytes: numBytes})
+	}
+
+	return sp, nil
+}
+
+// numBytes returns the number of bytes left to read in the current file's entry
+// in the tar archive, or 0 if there is no current file.
+func (tr *Reader) numBytes() int64 {
+	if tr.curr == nil {
+		// No current file, so no bytes
+		return 0
+	}
+	return tr.curr.numBytes()
+}
+
+// Read reads from the current entry in the tar archive.
+// It returns 0, io.EOF when it reaches the end of that entry,
+// until Next is called to advance to the next entry.
+func (tr *Reader) Read(b []byte) (n int, err error) {
+	if tr.curr == nil {
+		return 0, io.EOF
+	}
+	n, err = tr.curr.Read(b)
+	if err != nil && err != io.EOF {
+		tr.err = err
+	}
+	return
+}
+
+func (rfr *regFileReader) Read(b []byte) (n int, err error) {
+	if rfr.nb == 0 {
+		// file consumed
+		return 0, io.EOF
+	}
+	if int64(len(b)) > rfr.nb {
+		b = b[0:rfr.nb]
+	}
+	n, err = rfr.r.Read(b)
+	rfr.nb -= int64(n)
+
+	if err == io.EOF && rfr.nb > 0 {
+		err = io.ErrUnexpectedEOF
+	}
+	return
+}
+
+// numBytes returns the number of bytes left to read in the file's data in the tar archive.
+func (rfr *regFileReader) numBytes() int64 {
+	return rfr.nb
+}
+
+// readHole reads a sparse file hole ending at offset toOffset
+func (sfr *sparseFileReader) readHole(b []byte, toOffset int64) int {
+	n64 := toOffset - sfr.pos
+	if n64 > int64(len(b)) {
+		n64 = int64(len(b))
+	}
+	n := int(n64)
+	for i := 0; i < n; i++ {
+		b[i] = 0
+	}
+	sfr.pos += n64
+	return n
+}
+
+// Read reads the sparse file data in expanded form.
+func (sfr *sparseFileReader) Read(b []byte) (n int, err error) {
+	if len(sfr.sp) == 0 {
+		// No more data fragments to read from.
+		if sfr.pos < sfr.tot {
+			// We're in the last hole
+			n = sfr.readHole(b, sfr.tot)
+			return
+		}
+		// Otherwise, we're at the end of the file
+		return 0, io.EOF
+	}
+	if sfr.pos < sfr.sp[0].offset {
+		// We're in a hole
+		n = sfr.readHole(b, sfr.sp[0].offset)
+		return
+	}
+
+	// We're not in a hole, so we'll read from the next data fragment
+	posInFragment := sfr.pos - sfr.sp[0].offset
+	bytesLeft := sfr.sp[0].numBytes - posInFragment
+	if int64(len(b)) > bytesLeft {
+		b = b[0:bytesLeft]
+	}
+
+	n, err = sfr.rfr.Read(b)
+	sfr.pos += int64(n)
+
+	if int64(n) == bytesLeft {
+		// We're done with this fragment
+		sfr.sp = sfr.sp[1:]
+	}
+
+	if err == io.EOF && sfr.pos < sfr.tot {
+		// We reached the end of the last fragment's data, but there's a final hole
+		err = nil
+	}
+	return
+}
+
+// numBytes returns the number of bytes left to read in the sparse file's
+// sparse-encoded data in the tar archive.
+func (sfr *sparseFileReader) numBytes() int64 {
+	return sfr.rfr.nb
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/reader_test.go

@@ -0,0 +1,743 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar
+
+import (
+	"bytes"
+	"crypto/md5"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+)
+
+type untarTest struct {
+	file    string
+	headers []*Header
+	cksums  []string
+}
+
+var gnuTarTest = &untarTest{
+	file: "testdata/gnu.tar",
+	headers: []*Header{
+		{
+			Name:     "small.txt",
+			Mode:     0640,
+			Uid:      73025,
+			Gid:      5000,
+			Size:     5,
+			ModTime:  time.Unix(1244428340, 0),
+			Typeflag: '0',
+			Uname:    "dsymonds",
+			Gname:    "eng",
+		},
+		{
+			Name:     "small2.txt",
+			Mode:     0640,
+			Uid:      73025,
+			Gid:      5000,
+			Size:     11,
+			ModTime:  time.Unix(1244436044, 0),
+			Typeflag: '0',
+			Uname:    "dsymonds",
+			Gname:    "eng",
+		},
+	},
+	cksums: []string{
+		"e38b27eaccb4391bdec553a7f3ae6b2f",
+		"c65bd2e50a56a2138bf1716f2fd56fe9",
+	},
+}
+
+var sparseTarTest = &untarTest{
+	file: "testdata/sparse-formats.tar",
+	headers: []*Header{
+		{
+			Name:     "sparse-gnu",
+			Mode:     420,
+			Uid:      1000,
+			Gid:      1000,
+			Size:     200,
+			ModTime:  time.Unix(1392395740, 0),
+			Typeflag: 0x53,
+			Linkname: "",
+			Uname:    "david",
+			Gname:    "david",
+			Devmajor: 0,
+			Devminor: 0,
+		},
+		{
+			Name:     "sparse-posix-0.0",
+			Mode:     420,
+			Uid:      1000,
+			Gid:      1000,
+			Size:     200,
+			ModTime:  time.Unix(1392342187, 0),
+			Typeflag: 0x30,
+			Linkname: "",
+			Uname:    "david",
+			Gname:    "david",
+			Devmajor: 0,
+			Devminor: 0,
+		},
+		{
+			Name:     "sparse-posix-0.1",
+			Mode:     420,
+			Uid:      1000,
+			Gid:      1000,
+			Size:     200,
+			ModTime:  time.Unix(1392340456, 0),
+			Typeflag: 0x30,
+			Linkname: "",
+			Uname:    "david",
+			Gname:    "david",
+			Devmajor: 0,
+			Devminor: 0,
+		},
+		{
+			Name:     "sparse-posix-1.0",
+			Mode:     420,
+			Uid:      1000,
+			Gid:      1000,
+			Size:     200,
+			ModTime:  time.Unix(1392337404, 0),
+			Typeflag: 0x30,
+			Linkname: "",
+			Uname:    "david",
+			Gname:    "david",
+			Devmajor: 0,
+			Devminor: 0,
+		},
+		{
+			Name:     "end",
+			Mode:     420,
+			Uid:      1000,
+			Gid:      1000,
+			Size:     4,
+			ModTime:  time.Unix(1392398319, 0),
+			Typeflag: 0x30,
+			Linkname: "",
+			Uname:    "david",
+			Gname:    "david",
+			Devmajor: 0,
+			Devminor: 0,
+		},
+	},
+	cksums: []string{
+		"6f53234398c2449fe67c1812d993012f",
+		"6f53234398c2449fe67c1812d993012f",
+		"6f53234398c2449fe67c1812d993012f",
+		"6f53234398c2449fe67c1812d993012f",
+		"b0061974914468de549a2af8ced10316",
+	},
+}
+
+var untarTests = []*untarTest{
+	gnuTarTest,
+	sparseTarTest,
+	{
+		file: "testdata/star.tar",
+		headers: []*Header{
+			{
+				Name:       "small.txt",
+				Mode:       0640,
+				Uid:        73025,
+				Gid:        5000,
+				Size:       5,
+				ModTime:    time.Unix(1244592783, 0),
+				Typeflag:   '0',
+				Uname:      "dsymonds",
+				Gname:      "eng",
+				AccessTime: time.Unix(1244592783, 0),
+				ChangeTime: time.Unix(1244592783, 0),
+			},
+			{
+				Name:       "small2.txt",
+				Mode:       0640,
+				Uid:        73025,
+				Gid:        5000,
+				Size:       11,
+				ModTime:    time.Unix(1244592783, 0),
+				Typeflag:   '0',
+				Uname:      "dsymonds",
+				Gname:      "eng",
+				AccessTime: time.Unix(1244592783, 0),
+				ChangeTime: time.Unix(1244592783, 0),
+			},
+		},
+	},
+	{
+		file: "testdata/v7.tar",
+		headers: []*Header{
+			{
+				Name:     "small.txt",
+				Mode:     0444,
+				Uid:      73025,
+				Gid:      5000,
+				Size:     5,
+				ModTime:  time.Unix(1244593104, 0),
+				Typeflag: '\x00',
+			},
+			{
+				Name:     "small2.txt",
+				Mode:     0444,
+				Uid:      73025,
+				Gid:      5000,
+				Size:     11,
+				ModTime:  time.Unix(1244593104, 0),
+				Typeflag: '\x00',
+			},
+		},
+	},
+	{
+		file: "testdata/pax.tar",
+		headers: []*Header{
+			{
+				Name:       "a/123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100",
+				Mode:       0664,
+				Uid:        1000,
+				Gid:        1000,
+				Uname:      "shane",
+				Gname:      "shane",
+				Size:       7,
+				ModTime:    time.Unix(1350244992, 23960108),
+				ChangeTime: time.Unix(1350244992, 23960108),
+				AccessTime: time.Unix(1350244992, 23960108),
+				Typeflag:   TypeReg,
+			},
+			{
+				Name:       "a/b",
+				Mode:       0777,
+				Uid:        1000,
+				Gid:        1000,
+				Uname:      "shane",
+				Gname:      "shane",
+				Size:       0,
+				ModTime:    time.Unix(1350266320, 910238425),
+				ChangeTime: time.Unix(1350266320, 910238425),
+				AccessTime: time.Unix(1350266320, 910238425),
+				Typeflag:   TypeSymlink,
+				Linkname:   "123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100",
+			},
+		},
+	},
+	{
+		file: "testdata/nil-uid.tar", // golang.org/issue/5290
+		headers: []*Header{
+			{
+				Name:     "P1050238.JPG.log",
+				Mode:     0664,
+				Uid:      0,
+				Gid:      0,
+				Size:     14,
+				ModTime:  time.Unix(1365454838, 0),
+				Typeflag: TypeReg,
+				Linkname: "",
+				Uname:    "eyefi",
+				Gname:    "eyefi",
+				Devmajor: 0,
+				Devminor: 0,
+			},
+		},
+	},
+	{
+		file: "testdata/xattrs.tar",
+		headers: []*Header{
+			{
+				Name:       "small.txt",
+				Mode:       0644,
+				Uid:        1000,
+				Gid:        10,
+				Size:       5,
+				ModTime:    time.Unix(1386065770, 448252320),
+				Typeflag:   '0',
+				Uname:      "alex",
+				Gname:      "wheel",
+				AccessTime: time.Unix(1389782991, 419875220),
+				ChangeTime: time.Unix(1389782956, 794414986),
+				Xattrs: map[string]string{
+					"user.key":  "value",
+					"user.key2": "value2",
+					// Interestingly, selinux encodes the terminating null inside the xattr
+					"security.selinux": "unconfined_u:object_r:default_t:s0\x00",
+				},
+			},
+			{
+				Name:       "small2.txt",
+				Mode:       0644,
+				Uid:        1000,
+				Gid:        10,
+				Size:       11,
+				ModTime:    time.Unix(1386065770, 449252304),
+				Typeflag:   '0',
+				Uname:      "alex",
+				Gname:      "wheel",
+				AccessTime: time.Unix(1389782991, 419875220),
+				ChangeTime: time.Unix(1386065770, 449252304),
+				Xattrs: map[string]string{
+					"security.selinux": "unconfined_u:object_r:default_t:s0\x00",
+				},
+			},
+		},
+	},
+}
+
+func TestReader(t *testing.T) {
+testLoop:
+	for i, test := range untarTests {
+		f, err := os.Open(test.file)
+		if err != nil {
+			t.Errorf("test %d: Unexpected error: %v", i, err)
+			continue
+		}
+		defer f.Close()
+		tr := NewReader(f)
+		for j, header := range test.headers {
+			hdr, err := tr.Next()
+			if err != nil || hdr == nil {
+				t.Errorf("test %d, entry %d: Didn't get entry: %v", i, j, err)
+				f.Close()
+				continue testLoop
+			}
+			if !reflect.DeepEqual(*hdr, *header) {
+				t.Errorf("test %d, entry %d: Incorrect header:\nhave %+v\nwant %+v",
+					i, j, *hdr, *header)
+			}
+		}
+		hdr, err := tr.Next()
+		if err == io.EOF {
+			continue testLoop
+		}
+		if hdr != nil || err != nil {
+			t.Errorf("test %d: Unexpected entry or error: hdr=%v err=%v", i, hdr, err)
+		}
+	}
+}
+
+func TestPartialRead(t *testing.T) {
+	f, err := os.Open("testdata/gnu.tar")
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	defer f.Close()
+
+	tr := NewReader(f)
+
+	// Read the first four bytes; Next() should skip the last byte.
+	hdr, err := tr.Next()
+	if err != nil || hdr == nil {
+		t.Fatalf("Didn't get first file: %v", err)
+	}
+	buf := make([]byte, 4)
+	if _, err := io.ReadFull(tr, buf); err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if expected := []byte("Kilt"); !bytes.Equal(buf, expected) {
+		t.Errorf("Contents = %v, want %v", buf, expected)
+	}
+
+	// Second file
+	hdr, err = tr.Next()
+	if err != nil || hdr == nil {
+		t.Fatalf("Didn't get second file: %v", err)
+	}
+	buf = make([]byte, 6)
+	if _, err := io.ReadFull(tr, buf); err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	if expected := []byte("Google"); !bytes.Equal(buf, expected) {
+		t.Errorf("Contents = %v, want %v", buf, expected)
+	}
+}
+
+func TestIncrementalRead(t *testing.T) {
+	test := gnuTarTest
+	f, err := os.Open(test.file)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	defer f.Close()
+
+	tr := NewReader(f)
+
+	headers := test.headers
+	cksums := test.cksums
+	nread := 0
+
+	// loop over all files
+	for ; ; nread++ {
+		hdr, err := tr.Next()
+		if hdr == nil || err == io.EOF {
+			break
+		}
+
+		// check the header
+		if !reflect.DeepEqual(*hdr, *headers[nread]) {
+			t.Errorf("Incorrect header:\nhave %+v\nwant %+v",
+				*hdr, headers[nread])
+		}
+
+		// read file contents in little chunks EOF,
+		// checksumming all the way
+		h := md5.New()
+		rdbuf := make([]uint8, 8)
+		for {
+			nr, err := tr.Read(rdbuf)
+			if err == io.EOF {
+				break
+			}
+			if err != nil {
+				t.Errorf("Read: unexpected error %v\n", err)
+				break
+			}
+			h.Write(rdbuf[0:nr])
+		}
+		// verify checksum
+		have := fmt.Sprintf("%x", h.Sum(nil))
+		want := cksums[nread]
+		if want != have {
+			t.Errorf("Bad checksum on file %s:\nhave %+v\nwant %+v", hdr.Name, have, want)
+		}
+	}
+	if nread != len(headers) {
+		t.Errorf("Didn't process all files\nexpected: %d\nprocessed %d\n", len(headers), nread)
+	}
+}
+
+func TestNonSeekable(t *testing.T) {
+	test := gnuTarTest
+	f, err := os.Open(test.file)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	defer f.Close()
+
+	type readerOnly struct {
+		io.Reader
+	}
+	tr := NewReader(readerOnly{f})
+	nread := 0
+
+	for ; ; nread++ {
+		_, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatalf("Unexpected error: %v", err)
+		}
+	}
+
+	if nread != len(test.headers) {
+		t.Errorf("Didn't process all files\nexpected: %d\nprocessed %d\n", len(test.headers), nread)
+	}
+}
+
+func TestParsePAXHeader(t *testing.T) {
+	paxTests := [][3]string{
+		{"a", "a=name", "10 a=name\n"}, // Test case involving multiple acceptable lengths
+		{"a", "a=name", "9 a=name\n"},  // Test case involving multiple acceptable length
+		{"mtime", "mtime=1350244992.023960108", "30 mtime=1350244992.023960108\n"}}
+	for _, test := range paxTests {
+		key, expected, raw := test[0], test[1], test[2]
+		reader := bytes.NewReader([]byte(raw))
+		headers, err := parsePAX(reader)
+		if err != nil {
+			t.Errorf("Couldn't parse correctly formatted headers: %v", err)
+			continue
+		}
+		if strings.EqualFold(headers[key], expected) {
+			t.Errorf("mtime header incorrectly parsed: got %s, wanted %s", headers[key], expected)
+			continue
+		}
+		trailer := make([]byte, 100)
+		n, err := reader.Read(trailer)
+		if err != io.EOF || n != 0 {
+			t.Error("Buffer wasn't consumed")
+		}
+	}
+	badHeader := bytes.NewReader([]byte("3 somelongkey="))
+	if _, err := parsePAX(badHeader); err != ErrHeader {
+		t.Fatal("Unexpected success when parsing bad header")
+	}
+}
+
+func TestParsePAXTime(t *testing.T) {
+	// Some valid PAX time values
+	timestamps := map[string]time.Time{
+		"1350244992.023960108":  time.Unix(1350244992, 23960108), // The common case
+		"1350244992.02396010":   time.Unix(1350244992, 23960100), // Lower precision value
+		"1350244992.0239601089": time.Unix(1350244992, 23960108), // Higher precision value
+		"1350244992":            time.Unix(1350244992, 0),        // Low precision value
+	}
+	for input, expected := range timestamps {
+		ts, err := parsePAXTime(input)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !ts.Equal(expected) {
+			t.Fatalf("Time parsing failure %s %s", ts, expected)
+		}
+	}
+}
+
+func TestMergePAX(t *testing.T) {
+	hdr := new(Header)
+	// Test a string, integer, and time based value.
+	headers := map[string]string{
+		"path":  "a/b/c",
+		"uid":   "1000",
+		"mtime": "1350244992.023960108",
+	}
+	err := mergePAX(hdr, headers)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := &Header{
+		Name:    "a/b/c",
+		Uid:     1000,
+		ModTime: time.Unix(1350244992, 23960108),
+	}
+	if !reflect.DeepEqual(hdr, want) {
+		t.Errorf("incorrect merge: got %+v, want %+v", hdr, want)
+	}
+}
+
+func TestSparseEndToEnd(t *testing.T) {
+	test := sparseTarTest
+	f, err := os.Open(test.file)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	defer f.Close()
+
+	tr := NewReader(f)
+
+	headers := test.headers
+	cksums := test.cksums
+	nread := 0
+
+	// loop over all files
+	for ; ; nread++ {
+		hdr, err := tr.Next()
+		if hdr == nil || err == io.EOF {
+			break
+		}
+
+		// check the header
+		if !reflect.DeepEqual(*hdr, *headers[nread]) {
+			t.Errorf("Incorrect header:\nhave %+v\nwant %+v",
+				*hdr, headers[nread])
+		}
+
+		// read and checksum the file data
+		h := md5.New()
+		_, err = io.Copy(h, tr)
+		if err != nil {
+			t.Fatalf("Unexpected error: %v", err)
+		}
+
+		// verify checksum
+		have := fmt.Sprintf("%x", h.Sum(nil))
+		want := cksums[nread]
+		if want != have {
+			t.Errorf("Bad checksum on file %s:\nhave %+v\nwant %+v", hdr.Name, have, want)
+		}
+	}
+	if nread != len(headers) {
+		t.Errorf("Didn't process all files\nexpected: %d\nprocessed %d\n", len(headers), nread)
+	}
+}
+
+type sparseFileReadTest struct {
+	sparseData []byte
+	sparseMap  []sparseEntry
+	realSize   int64
+	expected   []byte
+}
+
+var sparseFileReadTests = []sparseFileReadTest{
+	{
+		sparseData: []byte("abcde"),
+		sparseMap: []sparseEntry{
+			{offset: 0, numBytes: 2},
+			{offset: 5, numBytes: 3},
+		},
+		realSize: 8,
+		expected: []byte("ab\x00\x00\x00cde"),
+	},
+	{
+		sparseData: []byte("abcde"),
+		sparseMap: []sparseEntry{
+			{offset: 0, numBytes: 2},
+			{offset: 5, numBytes: 3},
+		},
+		realSize: 10,
+		expected: []byte("ab\x00\x00\x00cde\x00\x00"),
+	},
+	{
+		sparseData: []byte("abcde"),
+		sparseMap: []sparseEntry{
+			{offset: 1, numBytes: 3},
+			{offset: 6, numBytes: 2},
+		},
+		realSize: 8,
+		expected: []byte("\x00abc\x00\x00de"),
+	},
+	{
+		sparseData: []byte("abcde"),
+		sparseMap: []sparseEntry{
+			{offset: 1, numBytes: 3},
+			{offset: 6, numBytes: 2},
+		},
+		realSize: 10,
+		expected: []byte("\x00abc\x00\x00de\x00\x00"),
+	},
+	{
+		sparseData: []byte(""),
+		sparseMap:  nil,
+		realSize:   2,
+		expected:   []byte("\x00\x00"),
+	},
+}
+
+func TestSparseFileReader(t *testing.T) {
+	for i, test := range sparseFileReadTests {
+		r := bytes.NewReader(test.sparseData)
+		nb := int64(r.Len())
+		sfr := &sparseFileReader{
+			rfr: &regFileReader{r: r, nb: nb},
+			sp:  test.sparseMap,
+			pos: 0,
+			tot: test.realSize,
+		}
+		if sfr.numBytes() != nb {
+			t.Errorf("test %d: Before reading, sfr.numBytes() = %d, want %d", i, sfr.numBytes(), nb)
+		}
+		buf, err := ioutil.ReadAll(sfr)
+		if err != nil {
+			t.Errorf("test %d: Unexpected error: %v", i, err)
+		}
+		if e := test.expected; !bytes.Equal(buf, e) {
+			t.Errorf("test %d: Contents = %v, want %v", i, buf, e)
+		}
+		if sfr.numBytes() != 0 {
+			t.Errorf("test %d: After draining the reader, numBytes() was nonzero", i)
+		}
+	}
+}
+
+func TestSparseIncrementalRead(t *testing.T) {
+	sparseMap := []sparseEntry{{10, 2}}
+	sparseData := []byte("Go")
+	expected := "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00Go\x00\x00\x00\x00\x00\x00\x00\x00"
+
+	r := bytes.NewReader(sparseData)
+	nb := int64(r.Len())
+	sfr := &sparseFileReader{
+		rfr: &regFileReader{r: r, nb: nb},
+		sp:  sparseMap,
+		pos: 0,
+		tot: int64(len(expected)),
+	}
+
+	// We'll read the data 6 bytes at a time, with a hole of size 10 at
+	// the beginning and one of size 8 at the end.
+	var outputBuf bytes.Buffer
+	buf := make([]byte, 6)
+	for {
+		n, err := sfr.Read(buf)
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Errorf("Read: unexpected error %v\n", err)
+		}
+		if n > 0 {
+			_, err := outputBuf.Write(buf[:n])
+			if err != nil {
+				t.Errorf("Write: unexpected error %v\n", err)
+			}
+		}
+	}
+	got := outputBuf.String()
+	if got != expected {
+		t.Errorf("Contents = %v, want %v", got, expected)
+	}
+}
+
+func TestReadGNUSparseMap0x1(t *testing.T) {
+	headers := map[string]string{
+		paxGNUSparseNumBlocks: "4",
+		paxGNUSparseMap:       "0,5,10,5,20,5,30,5",
+	}
+	expected := []sparseEntry{
+		{offset: 0, numBytes: 5},
+		{offset: 10, numBytes: 5},
+		{offset: 20, numBytes: 5},
+		{offset: 30, numBytes: 5},
+	}
+
+	sp, err := readGNUSparseMap0x1(headers)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if !reflect.DeepEqual(sp, expected) {
+		t.Errorf("Incorrect sparse map: got %v, wanted %v", sp, expected)
+	}
+}
+
+func TestReadGNUSparseMap1x0(t *testing.T) {
+	// This test uses lots of holes so the sparse header takes up more than two blocks
+	numEntries := 100
+	expected := make([]sparseEntry, 0, numEntries)
+	sparseMap := new(bytes.Buffer)
+
+	fmt.Fprintf(sparseMap, "%d\n", numEntries)
+	for i := 0; i < numEntries; i++ {
+		offset := int64(2048 * i)
+		numBytes := int64(1024)
+		expected = append(expected, sparseEntry{offset: offset, numBytes: numBytes})
+		fmt.Fprintf(sparseMap, "%d\n%d\n", offset, numBytes)
+	}
+
+	// Make the header the smallest multiple of blockSize that fits the sparseMap
+	headerBlocks := (sparseMap.Len() + blockSize - 1) / blockSize
+	bufLen := blockSize * headerBlocks
+	buf := make([]byte, bufLen)
+	copy(buf, sparseMap.Bytes())
+
+	// Get an reader to read the sparse map
+	r := bytes.NewReader(buf)
+
+	// Read the sparse map
+	sp, err := readGNUSparseMap1x0(r)
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+	if !reflect.DeepEqual(sp, expected) {
+		t.Errorf("Incorrect sparse map: got %v, wanted %v", sp, expected)
+	}
+}
+
+func TestUninitializedRead(t *testing.T) {
+	test := gnuTarTest
+	f, err := os.Open(test.file)
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+	defer f.Close()
+
+	tr := NewReader(f)
+	_, err = tr.Read([]byte{})
+	if err == nil || err != io.EOF {
+		t.Errorf("Unexpected error: %v, wanted %v", err, io.EOF)
+	}
+
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/stat_atim.go

@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux dragonfly openbsd solaris
+
+package tar
+
+import (
+	"syscall"
+	"time"
+)
+
+func statAtime(st *syscall.Stat_t) time.Time {
+	return time.Unix(st.Atim.Unix())
+}
+
+func statCtime(st *syscall.Stat_t) time.Time {
+	return time.Unix(st.Ctim.Unix())
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/stat_atimespec.go

@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin freebsd netbsd
+
+package tar
+
+import (
+	"syscall"
+	"time"
+)
+
+func statAtime(st *syscall.Stat_t) time.Time {
+	return time.Unix(st.Atimespec.Unix())
+}
+
+func statCtime(st *syscall.Stat_t) time.Time {
+	return time.Unix(st.Ctimespec.Unix())
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/stat_unix.go

@@ -0,0 +1,32 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build linux darwin dragonfly freebsd openbsd netbsd solaris
+
+package tar
+
+import (
+	"os"
+	"syscall"
+)
+
+func init() {
+	sysStat = statUnix
+}
+
+func statUnix(fi os.FileInfo, h *Header) error {
+	sys, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return nil
+	}
+	h.Uid = int(sys.Uid)
+	h.Gid = int(sys.Gid)
+	// TODO(bradfitz): populate username & group.  os/user
+	// doesn't cache LookupId lookups, and lacks group
+	// lookup functions.
+	h.AccessTime = statAtime(sys)
+	h.ChangeTime = statCtime(sys)
+	// TODO(bradfitz): major/minor device numbers?
+	return nil
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/tar_test.go

@@ -0,0 +1,284 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"path"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestFileInfoHeader(t *testing.T) {
+	fi, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	h, err := FileInfoHeader(fi, "")
+	if err != nil {
+		t.Fatalf("FileInfoHeader: %v", err)
+	}
+	if g, e := h.Name, "small.txt"; g != e {
+		t.Errorf("Name = %q; want %q", g, e)
+	}
+	if g, e := h.Mode, int64(fi.Mode().Perm())|c_ISREG; g != e {
+		t.Errorf("Mode = %#o; want %#o", g, e)
+	}
+	if g, e := h.Size, int64(5); g != e {
+		t.Errorf("Size = %v; want %v", g, e)
+	}
+	if g, e := h.ModTime, fi.ModTime(); !g.Equal(e) {
+		t.Errorf("ModTime = %v; want %v", g, e)
+	}
+	// FileInfoHeader should error when passing nil FileInfo
+	if _, err := FileInfoHeader(nil, ""); err == nil {
+		t.Fatalf("Expected error when passing nil to FileInfoHeader")
+	}
+}
+
+func TestFileInfoHeaderDir(t *testing.T) {
+	fi, err := os.Stat("testdata")
+	if err != nil {
+		t.Fatal(err)
+	}
+	h, err := FileInfoHeader(fi, "")
+	if err != nil {
+		t.Fatalf("FileInfoHeader: %v", err)
+	}
+	if g, e := h.Name, "testdata/"; g != e {
+		t.Errorf("Name = %q; want %q", g, e)
+	}
+	// Ignoring c_ISGID for golang.org/issue/4867
+	if g, e := h.Mode&^c_ISGID, int64(fi.Mode().Perm())|c_ISDIR; g != e {
+		t.Errorf("Mode = %#o; want %#o", g, e)
+	}
+	if g, e := h.Size, int64(0); g != e {
+		t.Errorf("Size = %v; want %v", g, e)
+	}
+	if g, e := h.ModTime, fi.ModTime(); !g.Equal(e) {
+		t.Errorf("ModTime = %v; want %v", g, e)
+	}
+}
+
+func TestFileInfoHeaderSymlink(t *testing.T) {
+	h, err := FileInfoHeader(symlink{}, "some-target")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if g, e := h.Name, "some-symlink"; g != e {
+		t.Errorf("Name = %q; want %q", g, e)
+	}
+	if g, e := h.Linkname, "some-target"; g != e {
+		t.Errorf("Linkname = %q; want %q", g, e)
+	}
+}
+
+type symlink struct{}
+
+func (symlink) Name() string       { return "some-symlink" }
+func (symlink) Size() int64        { return 0 }
+func (symlink) Mode() os.FileMode  { return os.ModeSymlink }
+func (symlink) ModTime() time.Time { return time.Time{} }
+func (symlink) IsDir() bool        { return false }
+func (symlink) Sys() interface{}   { return nil }
+
+func TestRoundTrip(t *testing.T) {
+	data := []byte("some file contents")
+
+	var b bytes.Buffer
+	tw := NewWriter(&b)
+	hdr := &Header{
+		Name:    "file.txt",
+		Uid:     1 << 21, // too big for 8 octal digits
+		Size:    int64(len(data)),
+		ModTime: time.Now(),
+	}
+	// tar only supports second precision.
+	hdr.ModTime = hdr.ModTime.Add(-time.Duration(hdr.ModTime.Nanosecond()) * time.Nanosecond)
+	if err := tw.WriteHeader(hdr); err != nil {
+		t.Fatalf("tw.WriteHeader: %v", err)
+	}
+	if _, err := tw.Write(data); err != nil {
+		t.Fatalf("tw.Write: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatalf("tw.Close: %v", err)
+	}
+
+	// Read it back.
+	tr := NewReader(&b)
+	rHdr, err := tr.Next()
+	if err != nil {
+		t.Fatalf("tr.Next: %v", err)
+	}
+	if !reflect.DeepEqual(rHdr, hdr) {
+		t.Errorf("Header mismatch.\n got %+v\nwant %+v", rHdr, hdr)
+	}
+	rData, err := ioutil.ReadAll(tr)
+	if err != nil {
+		t.Fatalf("Read: %v", err)
+	}
+	if !bytes.Equal(rData, data) {
+		t.Errorf("Data mismatch.\n got %q\nwant %q", rData, data)
+	}
+}
+
+type headerRoundTripTest struct {
+	h  *Header
+	fm os.FileMode
+}
+
+func TestHeaderRoundTrip(t *testing.T) {
+	golden := []headerRoundTripTest{
+		// regular file.
+		{
+			h: &Header{
+				Name:     "test.txt",
+				Mode:     0644 | c_ISREG,
+				Size:     12,
+				ModTime:  time.Unix(1360600916, 0),
+				Typeflag: TypeReg,
+			},
+			fm: 0644,
+		},
+		// hard link.
+		{
+			h: &Header{
+				Name:     "hard.txt",
+				Mode:     0644 | c_ISLNK,
+				Size:     0,
+				ModTime:  time.Unix(1360600916, 0),
+				Typeflag: TypeLink,
+			},
+			fm: 0644 | os.ModeSymlink,
+		},
+		// symbolic link.
+		{
+			h: &Header{
+				Name:     "link.txt",
+				Mode:     0777 | c_ISLNK,
+				Size:     0,
+				ModTime:  time.Unix(1360600852, 0),
+				Typeflag: TypeSymlink,
+			},
+			fm: 0777 | os.ModeSymlink,
+		},
+		// character device node.
+		{
+			h: &Header{
+				Name:     "dev/null",
+				Mode:     0666 | c_ISCHR,
+				Size:     0,
+				ModTime:  time.Unix(1360578951, 0),
+				Typeflag: TypeChar,
+			},
+			fm: 0666 | os.ModeDevice | os.ModeCharDevice,
+		},
+		// block device node.
+		{
+			h: &Header{
+				Name:     "dev/sda",
+				Mode:     0660 | c_ISBLK,
+				Size:     0,
+				ModTime:  time.Unix(1360578954, 0),
+				Typeflag: TypeBlock,
+			},
+			fm: 0660 | os.ModeDevice,
+		},
+		// directory.
+		{
+			h: &Header{
+				Name:     "dir/",
+				Mode:     0755 | c_ISDIR,
+				Size:     0,
+				ModTime:  time.Unix(1360601116, 0),
+				Typeflag: TypeDir,
+			},
+			fm: 0755 | os.ModeDir,
+		},
+		// fifo node.
+		{
+			h: &Header{
+				Name:     "dev/initctl",
+				Mode:     0600 | c_ISFIFO,
+				Size:     0,
+				ModTime:  time.Unix(1360578949, 0),
+				Typeflag: TypeFifo,
+			},
+			fm: 0600 | os.ModeNamedPipe,
+		},
+		// setuid.
+		{
+			h: &Header{
+				Name:     "bin/su",
+				Mode:     0755 | c_ISREG | c_ISUID,
+				Size:     23232,
+				ModTime:  time.Unix(1355405093, 0),
+				Typeflag: TypeReg,
+			},
+			fm: 0755 | os.ModeSetuid,
+		},
+		// setguid.
+		{
+			h: &Header{
+				Name:     "group.txt",
+				Mode:     0750 | c_ISREG | c_ISGID,
+				Size:     0,
+				ModTime:  time.Unix(1360602346, 0),
+				Typeflag: TypeReg,
+			},
+			fm: 0750 | os.ModeSetgid,
+		},
+		// sticky.
+		{
+			h: &Header{
+				Name:     "sticky.txt",
+				Mode:     0600 | c_ISREG | c_ISVTX,
+				Size:     7,
+				ModTime:  time.Unix(1360602540, 0),
+				Typeflag: TypeReg,
+			},
+			fm: 0600 | os.ModeSticky,
+		},
+	}
+
+	for i, g := range golden {
+		fi := g.h.FileInfo()
+		h2, err := FileInfoHeader(fi, "")
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+		if strings.Contains(fi.Name(), "/") {
+			t.Errorf("FileInfo of %q contains slash: %q", g.h.Name, fi.Name())
+		}
+		name := path.Base(g.h.Name)
+		if fi.IsDir() {
+			name += "/"
+		}
+		if got, want := h2.Name, name; got != want {
+			t.Errorf("i=%d: Name: got %v, want %v", i, got, want)
+		}
+		if got, want := h2.Size, g.h.Size; got != want {
+			t.Errorf("i=%d: Size: got %v, want %v", i, got, want)
+		}
+		if got, want := h2.Mode, g.h.Mode; got != want {
+			t.Errorf("i=%d: Mode: got %o, want %o", i, got, want)
+		}
+		if got, want := fi.Mode(), g.fm; got != want {
+			t.Errorf("i=%d: fi.Mode: got %o, want %o", i, got, want)
+		}
+		if got, want := h2.ModTime, g.h.ModTime; got != want {
+			t.Errorf("i=%d: ModTime: got %v, want %v", i, got, want)
+		}
+		if sysh, ok := fi.Sys().(*Header); !ok || sysh != g.h {
+			t.Errorf("i=%d: Sys didn't return original *Header", i)
+		}
+	}
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/testdata/small.txt

@@ -0,0 +1 @@
+Kilts

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/testdata/small2.txt

@@ -0,0 +1 @@
+Google.com

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/writer.go

@@ -0,0 +1,396 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar
+
+// TODO(dsymonds):
+// - catch more errors (no first header, etc.)
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	ErrWriteTooLong    = errors.New("archive/tar: write too long")
+	ErrFieldTooLong    = errors.New("archive/tar: header field too long")
+	ErrWriteAfterClose = errors.New("archive/tar: write after close")
+	errNameTooLong     = errors.New("archive/tar: name too long")
+	errInvalidHeader   = errors.New("archive/tar: header field too long or contains invalid values")
+)
+
+// A Writer provides sequential writing of a tar archive in POSIX.1 format.
+// A tar archive consists of a sequence of files.
+// Call WriteHeader to begin a new file, and then call Write to supply that file's data,
+// writing at most hdr.Size bytes in total.
+type Writer struct {
+	w          io.Writer
+	err        error
+	nb         int64 // number of unwritten bytes for current file entry
+	pad        int64 // amount of padding to write after current file entry
+	closed     bool
+	usedBinary bool            // whether the binary numeric field extension was used
+	preferPax  bool            // use pax header instead of binary numeric header
+	hdrBuff    [blockSize]byte // buffer to use in writeHeader when writing a regular header
+	paxHdrBuff [blockSize]byte // buffer to use in writeHeader when writing a pax header
+}
+
+// NewWriter creates a new Writer writing to w.
+func NewWriter(w io.Writer) *Writer { return &Writer{w: w} }
+
+// Flush finishes writing the current file (optional).
+func (tw *Writer) Flush() error {
+	if tw.nb > 0 {
+		tw.err = fmt.Errorf("archive/tar: missed writing %d bytes", tw.nb)
+		return tw.err
+	}
+
+	n := tw.nb + tw.pad
+	for n > 0 && tw.err == nil {
+		nr := n
+		if nr > blockSize {
+			nr = blockSize
+		}
+		var nw int
+		nw, tw.err = tw.w.Write(zeroBlock[0:nr])
+		n -= int64(nw)
+	}
+	tw.nb = 0
+	tw.pad = 0
+	return tw.err
+}
+
+// Write s into b, terminating it with a NUL if there is room.
+// If the value is too long for the field and allowPax is true add a paxheader record instead
+func (tw *Writer) cString(b []byte, s string, allowPax bool, paxKeyword string, paxHeaders map[string]string) {
+	needsPaxHeader := allowPax && len(s) > len(b) || !isASCII(s)
+	if needsPaxHeader {
+		paxHeaders[paxKeyword] = s
+		return
+	}
+	if len(s) > len(b) {
+		if tw.err == nil {
+			tw.err = ErrFieldTooLong
+		}
+		return
+	}
+	ascii := toASCII(s)
+	copy(b, ascii)
+	if len(ascii) < len(b) {
+		b[len(ascii)] = 0
+	}
+}
+
+// Encode x as an octal ASCII string and write it into b with leading zeros.
+func (tw *Writer) octal(b []byte, x int64) {
+	s := strconv.FormatInt(x, 8)
+	// leading zeros, but leave room for a NUL.
+	for len(s)+1 < len(b) {
+		s = "0" + s
+	}
+	tw.cString(b, s, false, paxNone, nil)
+}
+
+// Write x into b, either as octal or as binary (GNUtar/star extension).
+// If the value is too long for the field and writingPax is enabled both for the field and the add a paxheader record instead
+func (tw *Writer) numeric(b []byte, x int64, allowPax bool, paxKeyword string, paxHeaders map[string]string) {
+	// Try octal first.
+	s := strconv.FormatInt(x, 8)
+	if len(s) < len(b) {
+		tw.octal(b, x)
+		return
+	}
+
+	// If it is too long for octal, and pax is preferred, use a pax header
+	if allowPax && tw.preferPax {
+		tw.octal(b, 0)
+		s := strconv.FormatInt(x, 10)
+		paxHeaders[paxKeyword] = s
+		return
+	}
+
+	// Too big: use binary (big-endian).
+	tw.usedBinary = true
+	for i := len(b) - 1; x > 0 && i >= 0; i-- {
+		b[i] = byte(x)
+		x >>= 8
+	}
+	b[0] |= 0x80 // highest bit indicates binary format
+}
+
+var (
+	minTime = time.Unix(0, 0)
+	// There is room for 11 octal digits (33 bits) of mtime.
+	maxTime = minTime.Add((1<<33 - 1) * time.Second)
+)
+
+// WriteHeader writes hdr and prepares to accept the file's contents.
+// WriteHeader calls Flush if it is not the first header.
+// Calling after a Close will return ErrWriteAfterClose.
+func (tw *Writer) WriteHeader(hdr *Header) error {
+	return tw.writeHeader(hdr, true)
+}
+
+// WriteHeader writes hdr and prepares to accept the file's contents.
+// WriteHeader calls Flush if it is not the first header.
+// Calling after a Close will return ErrWriteAfterClose.
+// As this method is called internally by writePax header to allow it to
+// suppress writing the pax header.
+func (tw *Writer) writeHeader(hdr *Header, allowPax bool) error {
+	if tw.closed {
+		return ErrWriteAfterClose
+	}
+	if tw.err == nil {
+		tw.Flush()
+	}
+	if tw.err != nil {
+		return tw.err
+	}
+
+	// a map to hold pax header records, if any are needed
+	paxHeaders := make(map[string]string)
+
+	// TODO(shanemhansen): we might want to use PAX headers for
+	// subsecond time resolution, but for now let's just capture
+	// too long fields or non ascii characters
+
+	var header []byte
+
+	// We need to select which scratch buffer to use carefully,
+	// since this method is called recursively to write PAX headers.
+	// If allowPax is true, this is the non-recursive call, and we will use hdrBuff.
+	// If allowPax is false, we are being called by writePAXHeader, and hdrBuff is
+	// already being used by the non-recursive call, so we must use paxHdrBuff.
+	header = tw.hdrBuff[:]
+	if !allowPax {
+		header = tw.paxHdrBuff[:]
+	}
+	copy(header, zeroBlock)
+	s := slicer(header)
+
+	// keep a reference to the filename to allow to overwrite it later if we detect that we can use ustar longnames instead of pax
+	pathHeaderBytes := s.next(fileNameSize)
+
+	tw.cString(pathHeaderBytes, hdr.Name, true, paxPath, paxHeaders)
+
+	// Handle out of range ModTime carefully.
+	var modTime int64
+	if !hdr.ModTime.Before(minTime) && !hdr.ModTime.After(maxTime) {
+		modTime = hdr.ModTime.Unix()
+	}
+
+	tw.octal(s.next(8), hdr.Mode)                                   // 100:108
+	tw.numeric(s.next(8), int64(hdr.Uid), true, paxUid, paxHeaders) // 108:116
+	tw.numeric(s.next(8), int64(hdr.Gid), true, paxGid, paxHeaders) // 116:124
+	tw.numeric(s.next(12), hdr.Size, true, paxSize, paxHeaders)     // 124:136
+	tw.numeric(s.next(12), modTime, false, paxNone, nil)            // 136:148 --- consider using pax for finer granularity
+	s.next(8)                                                       // chksum (148:156)
+	s.next(1)[0] = hdr.Typeflag                                     // 156:157
+
+	tw.cString(s.next(100), hdr.Linkname, true, paxLinkpath, paxHeaders)
+
+	copy(s.next(8), []byte("ustar\x0000"))                        // 257:265
+	tw.cString(s.next(32), hdr.Uname, true, paxUname, paxHeaders) // 265:297
+	tw.cString(s.next(32), hdr.Gname, true, paxGname, paxHeaders) // 297:329
+	tw.numeric(s.next(8), hdr.Devmajor, false, paxNone, nil)      // 329:337
+	tw.numeric(s.next(8), hdr.Devminor, false, paxNone, nil)      // 337:345
+
+	// keep a reference to the prefix to allow to overwrite it later if we detect that we can use ustar longnames instead of pax
+	prefixHeaderBytes := s.next(155)
+	tw.cString(prefixHeaderBytes, "", false, paxNone, nil) // 345:500  prefix
+
+	// Use the GNU magic instead of POSIX magic if we used any GNU extensions.
+	if tw.usedBinary {
+		copy(header[257:265], []byte("ustar  \x00"))
+	}
+
+	_, paxPathUsed := paxHeaders[paxPath]
+	// try to use a ustar header when only the name is too long
+	if !tw.preferPax && len(paxHeaders) == 1 && paxPathUsed {
+		suffix := hdr.Name
+		prefix := ""
+		if len(hdr.Name) > fileNameSize && isASCII(hdr.Name) {
+			var err error
+			prefix, suffix, err = tw.splitUSTARLongName(hdr.Name)
+			if err == nil {
+				// ok we can use a ustar long name instead of pax, now correct the fields
+
+				// remove the path field from the pax header. this will suppress the pax header
+				delete(paxHeaders, paxPath)
+
+				// update the path fields
+				tw.cString(pathHeaderBytes, suffix, false, paxNone, nil)
+				tw.cString(prefixHeaderBytes, prefix, false, paxNone, nil)
+
+				// Use the ustar magic if we used ustar long names.
+				if len(prefix) > 0 && !tw.usedBinary {
+					copy(header[257:265], []byte("ustar\x00"))
+				}
+			}
+		}
+	}
+
+	// The chksum field is terminated by a NUL and a space.
+	// This is different from the other octal fields.
+	chksum, _ := checksum(header)
+	tw.octal(header[148:155], chksum)
+	header[155] = ' '
+
+	if tw.err != nil {
+		// problem with header; probably integer too big for a field.
+		return tw.err
+	}
+
+	if allowPax {
+		for k, v := range hdr.Xattrs {
+			paxHeaders[paxXattr+k] = v
+		}
+	}
+
+	if len(paxHeaders) > 0 {
+		if !allowPax {
+			return errInvalidHeader
+		}
+		if err := tw.writePAXHeader(hdr, paxHeaders); err != nil {
+			return err
+		}
+	}
+	tw.nb = int64(hdr.Size)
+	tw.pad = (blockSize - (tw.nb % blockSize)) % blockSize
+
+	_, tw.err = tw.w.Write(header)
+	return tw.err
+}
+
+// writeUSTARLongName splits a USTAR long name hdr.Name.
+// name must be < 256 characters. errNameTooLong is returned
+// if hdr.Name can't be split. The splitting heuristic
+// is compatible with gnu tar.
+func (tw *Writer) splitUSTARLongName(name string) (prefix, suffix string, err error) {
+	length := len(name)
+	if length > fileNamePrefixSize+1 {
+		length = fileNamePrefixSize + 1
+	} else if name[length-1] == '/' {
+		length--
+	}
+	i := strings.LastIndex(name[:length], "/")
+	// nlen contains the resulting length in the name field.
+	// plen contains the resulting length in the prefix field.
+	nlen := len(name) - i - 1
+	plen := i
+	if i <= 0 || nlen > fileNameSize || nlen == 0 || plen > fileNamePrefixSize {
+		err = errNameTooLong
+		return
+	}
+	prefix, suffix = name[:i], name[i+1:]
+	return
+}
+
+// writePaxHeader writes an extended pax header to the
+// archive.
+func (tw *Writer) writePAXHeader(hdr *Header, paxHeaders map[string]string) error {
+	// Prepare extended header
+	ext := new(Header)
+	ext.Typeflag = TypeXHeader
+	// Setting ModTime is required for reader parsing to
+	// succeed, and seems harmless enough.
+	ext.ModTime = hdr.ModTime
+	// The spec asks that we namespace our pseudo files
+	// with the current pid.
+	pid := os.Getpid()
+	dir, file := path.Split(hdr.Name)
+	fullName := path.Join(dir,
+		fmt.Sprintf("PaxHeaders.%d", pid), file)
+
+	ascii := toASCII(fullName)
+	if len(ascii) > 100 {
+		ascii = ascii[:100]
+	}
+	ext.Name = ascii
+	// Construct the body
+	var buf bytes.Buffer
+
+	for k, v := range paxHeaders {
+		fmt.Fprint(&buf, paxHeader(k+"="+v))
+	}
+
+	ext.Size = int64(len(buf.Bytes()))
+	if err := tw.writeHeader(ext, false); err != nil {
+		return err
+	}
+	if _, err := tw.Write(buf.Bytes()); err != nil {
+		return err
+	}
+	if err := tw.Flush(); err != nil {
+		return err
+	}
+	return nil
+}
+
+// paxHeader formats a single pax record, prefixing it with the appropriate length
+func paxHeader(msg string) string {
+	const padding = 2 // Extra padding for space and newline
+	size := len(msg) + padding
+	size += len(strconv.Itoa(size))
+	record := fmt.Sprintf("%d %s\n", size, msg)
+	if len(record) != size {
+		// Final adjustment if adding size increased
+		// the number of digits in size
+		size = len(record)
+		record = fmt.Sprintf("%d %s\n", size, msg)
+	}
+	return record
+}
+
+// Write writes to the current entry in the tar archive.
+// Write returns the error ErrWriteTooLong if more than
+// hdr.Size bytes are written after WriteHeader.
+func (tw *Writer) Write(b []byte) (n int, err error) {
+	if tw.closed {
+		err = ErrWriteTooLong
+		return
+	}
+	overwrite := false
+	if int64(len(b)) > tw.nb {
+		b = b[0:tw.nb]
+		overwrite = true
+	}
+	n, err = tw.w.Write(b)
+	tw.nb -= int64(n)
+	if err == nil && overwrite {
+		err = ErrWriteTooLong
+		return
+	}
+	tw.err = err
+	return
+}
+
+// Close closes the tar archive, flushing any unwritten
+// data to the underlying writer.
+func (tw *Writer) Close() error {
+	if tw.err != nil || tw.closed {
+		return tw.err
+	}
+	tw.Flush()
+	tw.closed = true
+	if tw.err != nil {
+		return tw.err
+	}
+
+	// trailer: two zero blocks
+	for i := 0; i < 2; i++ {
+		_, tw.err = tw.w.Write(zeroBlock)
+		if tw.err != nil {
+			break
+		}
+	}
+	return tw.err
+}

Godeps/_workspace/src/github.com/docker/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar/writer_test.go

@@ -0,0 +1,491 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tar
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+	"testing/iotest"
+	"time"
+)
+
+type writerTestEntry struct {
+	header   *Header
+	contents string
+}
+
+type writerTest struct {
+	file    string // filename of expected output
+	entries []*writerTestEntry
+}
+
+var writerTests = []*writerTest{
+	// The writer test file was produced with this command:
+	// tar (GNU tar) 1.26
+	//   ln -s small.txt link.txt
+	//   tar -b 1 --format=ustar -c -f writer.tar small.txt small2.txt link.txt
+	{
+		file: "testdata/writer.tar",
+		entries: []*writerTestEntry{
+			{
+				header: &Header{
+					Name:     "small.txt",
+					Mode:     0640,
+					Uid:      73025,
+					Gid:      5000,
+					Size:     5,
+					ModTime:  time.Unix(1246508266, 0),
+					Typeflag: '0',
+					Uname:    "dsymonds",
+					Gname:    "eng",
+				},
+				contents: "Kilts",
+			},
+			{
+				header: &Header{
+					Name:     "small2.txt",
+					Mode:     0640,
+					Uid:      73025,
+					Gid:      5000,
+					Size:     11,
+					ModTime:  time.Unix(1245217492, 0),
+					Typeflag: '0',
+					Uname:    "dsymonds",
+					Gname:    "eng",
+				},
+				contents: "Google.com\n",
+			},
+			{
+				header: &Header{
+					Name:     "link.txt",
+					Mode:     0777,
+					Uid:      1000,
+					Gid:      1000,
+					Size:     0,
+					ModTime:  time.Unix(1314603082, 0),
+					Typeflag: '2',
+					Linkname: "small.txt",
+					Uname:    "strings",
+					Gname:    "strings",
+				},
+				// no contents
+			},
+		},
+	},
+	// The truncated test file was produced using these commands:
+	//   dd if=/dev/zero bs=1048576 count=16384 > /tmp/16gig.txt
+	//   tar -b 1 -c -f- /tmp/16gig.txt | dd bs=512 count=8 > writer-big.tar
+	{
+		file: "testdata/writer-big.tar",
+		entries: []*writerTestEntry{
+			{
+				header: &Header{
+					Name:     "tmp/16gig.txt",
+					Mode:     0640,
+					Uid:      73025,
+					Gid:      5000,
+					Size:     16 << 30,
+					ModTime:  time.Unix(1254699560, 0),
+					Typeflag: '0',
+					Uname:    "dsymonds",
+					Gname:    "eng",
+				},
+				// fake contents
+				contents: strings.Repeat("\x00", 4<<10),
+			},
+		},
+	},
+	// The truncated test file was produced using these commands:
+	//   dd if=/dev/zero bs=1048576 count=16384 > (longname/)*15 /16gig.txt
+	//   tar -b 1 -c -f- (longname/)*15 /16gig.txt | dd bs=512 count=8 > writer-big-long.tar
+	{
+		file: "testdata/writer-big-long.tar",
+		entries: []*writerTestEntry{
+			{
+				header: &Header{
+					Name:     strings.Repeat("longname/", 15) + "16gig.txt",
+					Mode:     0644,
+					Uid:      1000,
+					Gid:      1000,
+					Size:     16 << 30,
+					ModTime:  time.Unix(1399583047, 0),
+					Typeflag: '0',
+					Uname:    "guillaume",
+					Gname:    "guillaume",
+				},
+				// fake contents
+				contents: strings.Repeat("\x00", 4<<10),
+			},
+		},
+	},
+	// This file was produced using gnu tar 1.17
+	// gnutar  -b 4 --format=ustar (longname/)*15 + file.txt
+	{
+		file: "testdata/ustar.tar",
+		entries: []*writerTestEntry{
+			{
+				header: &Header{
+					Name:     strings.Repeat("longname/", 15) + "file.txt",
+					Mode:     0644,
+					Uid:      0765,
+					Gid:      024,
+					Size:     06,
+					ModTime:  time.Unix(1360135598, 0),
+					Typeflag: '0',
+					Uname:    "shane",
+					Gname:    "staff",
+				},
+				contents: "hello\n",
+			},
+		},
+	},
+}
+
+// Render byte array in a two-character hexadecimal string, spaced for easy visual inspection.
+func bytestr(offset int, b []byte) string {
+	const rowLen = 32
+	s := fmt.Sprintf("%04x ", offset)
+	for _, ch := range b {
+		switch {
+		case '0' <= ch && ch <= '9', 'A' <= ch && ch <= 'Z', 'a' <= ch && ch <= 'z':
+			s += fmt.Sprintf("  %c", ch)
+		default:
+			s += fmt.Sprintf(" %02x", ch)
+		}
+	}
+	return s
+}
+
+// Render a pseudo-diff between two blocks of bytes.
+func bytediff(a []byte, b []byte) string {
+	const rowLen = 32
+	s := fmt.Sprintf("(%d bytes vs. %d bytes)\n", len(a), len(b))
+	for offset := 0; len(a)+len(b) > 0; offset += rowLen {
+		na, nb := rowLen, rowLen
+		if na > len(a) {
+			na = len(a)
+		}
+		if nb > len(b) {
+			nb = len(b)
+		}
+		sa := bytestr(offset, a[0:na])
+		sb := bytestr(offset, b[0:nb])
+		if sa != sb {
+			s += fmt.Sprintf("-%v\n+%v\n", sa, sb)
+		}
+		a = a[na:]
+		b = b[nb:]
+	}
+	return s
+}
+
+func TestWriter(t *testing.T) {
+testLoop:
+	for i, test := range writerTests {
+		expected, err := ioutil.ReadFile(test.file)
+		if err != nil {
+			t.Errorf("test %d: Unexpected error: %v", i, err)
+			continue
+		}
+
+		buf := new(bytes.Buffer)
+		tw := NewWriter(iotest.TruncateWriter(buf, 4<<10)) // only catch the first 4 KB
+		big := false
+		for j, entry := range test.entries {
+			big = big || entry.header.Size > 1<<10
+			if err := tw.WriteHeader(entry.header); err != nil {
+				t.Errorf("test %d, entry %d: Failed writing header: %v", i, j, err)
+				continue testLoop
+			}
+			if _, err := io.WriteString(tw, entry.contents); err != nil {
+				t.Errorf("test %d, entry %d: Failed writing contents: %v", i, j, err)
+				continue testLoop
+			}
+		}
+		// Only interested in Close failures for the small tests.
+		if err := tw.Close(); err != nil && !big {
+			t.Errorf("test %d: Failed closing archive: %v", i, err)
+			continue testLoop
+		}
+
+		actual := buf.Bytes()
+		if !bytes.Equal(expected, actual) {
+			t.Errorf("test %d: Incorrect result: (-=expected, +=actual)\n%v",
+				i, bytediff(expected, actual))
+		}
+		if testing.Short() { // The second test is expensive.
+			break
+		}
+	}
+}
+
+func TestPax(t *testing.T) {
+	// Create an archive with a large name
+	fileinfo, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	hdr, err := FileInfoHeader(fileinfo, "")
+	if err != nil {
+		t.Fatalf("os.Stat: %v", err)
+	}
+	// Force a PAX long name to be written
+	longName := strings.Repeat("ab", 100)
+	contents := strings.Repeat(" ", int(hdr.Size))
+	hdr.Name = longName
+	var buf bytes.Buffer
+	writer := NewWriter(&buf)
+	if err := writer.WriteHeader(hdr); err != nil {
+		t.Fatal(err)
+	}
+	if _, err = writer.Write([]byte(contents)); err != nil {
+		t.Fatal(err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatal(err)
+	}
+	// Simple test to make sure PAX extensions are in effect
+	if !bytes.Contains(buf.Bytes(), []byte("PaxHeaders.")) {
+		t.Fatal("Expected at least one PAX header to be written.")
+	}
+	// Test that we can get a long name back out of the archive.
+	reader := NewReader(&buf)
+	hdr, err = reader.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if hdr.Name != longName {
+		t.Fatal("Couldn't recover long file name")
+	}
+}
+
+func TestPaxSymlink(t *testing.T) {
+	// Create an archive with a large linkname
+	fileinfo, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	hdr, err := FileInfoHeader(fileinfo, "")
+	hdr.Typeflag = TypeSymlink
+	if err != nil {
+		t.Fatalf("os.Stat:1 %v", err)
+	}
+	// Force a PAX long linkname to be written
+	longLinkname := strings.Repeat("1234567890/1234567890", 10)
+	hdr.Linkname = longLinkname
+
+	hdr.Size = 0
+	var buf bytes.Buffer
+	writer := NewWriter(&buf)
+	if err := writer.WriteHeader(hdr); err != nil {
+		t.Fatal(err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatal(err)
+	}
+	// Simple test to make sure PAX extensions are in effect
+	if !bytes.Contains(buf.Bytes(), []byte("PaxHeaders.")) {
+		t.Fatal("Expected at least one PAX header to be written.")
+	}
+	// Test that we can get a long name back out of the archive.
+	reader := NewReader(&buf)
+	hdr, err = reader.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if hdr.Linkname != longLinkname {
+		t.Fatal("Couldn't recover long link name")
+	}
+}
+
+func TestPaxNonAscii(t *testing.T) {
+	// Create an archive with non ascii. These should trigger a pax header
+	// because pax headers have a defined utf-8 encoding.
+	fileinfo, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	hdr, err := FileInfoHeader(fileinfo, "")
+	if err != nil {
+		t.Fatalf("os.Stat:1 %v", err)
+	}
+
+	// some sample data
+	chineseFilename := "文件名"
+	chineseGroupname := "組"
+	chineseUsername := "用戶名"
+
+	hdr.Name = chineseFilename
+	hdr.Gname = chineseGroupname
+	hdr.Uname = chineseUsername
+
+	contents := strings.Repeat(" ", int(hdr.Size))
+
+	var buf bytes.Buffer
+	writer := NewWriter(&buf)
+	if err := writer.WriteHeader(hdr); err != nil {
+		t.Fatal(err)
+	}
+	if _, err = writer.Write([]byte(contents)); err != nil {
+		t.Fatal(err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatal(err)
+	}
+	// Simple test to make sure PAX extensions are in effect
+	if !bytes.Contains(buf.Bytes(), []byte("PaxHeaders.")) {
+		t.Fatal("Expected at least one PAX header to be written.")
+	}
+	// Test that we can get a long name back out of the archive.
+	reader := NewReader(&buf)
+	hdr, err = reader.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if hdr.Name != chineseFilename {
+		t.Fatal("Couldn't recover unicode name")
+	}
+	if hdr.Gname != chineseGroupname {
+		t.Fatal("Couldn't recover unicode group")
+	}
+	if hdr.Uname != chineseUsername {
+		t.Fatal("Couldn't recover unicode user")
+	}
+}
+
+func TestPaxXattrs(t *testing.T) {
+	xattrs := map[string]string{
+		"user.key": "value",
+	}
+
+	// Create an archive with an xattr
+	fileinfo, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	hdr, err := FileInfoHeader(fileinfo, "")
+	if err != nil {
+		t.Fatalf("os.Stat: %v", err)
+	}
+	contents := "Kilts"
+	hdr.Xattrs = xattrs
+	var buf bytes.Buffer
+	writer := NewWriter(&buf)
+	if err := writer.WriteHeader(hdr); err != nil {
+		t.Fatal(err)
+	}
+	if _, err = writer.Write([]byte(contents)); err != nil {
+		t.Fatal(err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatal(err)
+	}
+	// Test that we can get the xattrs back out of the archive.
+	reader := NewReader(&buf)
+	hdr, err = reader.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(hdr.Xattrs, xattrs) {
+		t.Fatalf("xattrs did not survive round trip: got %+v, want %+v",
+			hdr.Xattrs, xattrs)
+	}
+}
+
+func TestPAXHeader(t *testing.T) {
+	medName := strings.Repeat("CD", 50)
+	longName := strings.Repeat("AB", 100)
+	paxTests := [][2]string{
+		{paxPath + "=/etc/hosts", "19 path=/etc/hosts\n"},
+		{"a=b", "6 a=b\n"},          // Single digit length
+		{"a=names", "11 a=names\n"}, // Test case involving carries
+		{paxPath + "=" + longName, fmt.Sprintf("210 path=%s\n", longName)},
+		{paxPath + "=" + medName, fmt.Sprintf("110 path=%s\n", medName)}}
+
+	for _, test := range paxTests {
+		key, expected := test[0], test[1]
+		if result := paxHeader(key); result != expected {
+			t.Fatalf("paxHeader: got %s, expected %s", result, expected)
+		}
+	}
+}
+
+func TestUSTARLongName(t *testing.T) {
+	// Create an archive with a path that failed to split with USTAR extension in previous versions.
+	fileinfo, err := os.Stat("testdata/small.txt")
+	if err != nil {
+		t.Fatal(err)
+	}
+	hdr, err := FileInfoHeader(fileinfo, "")
+	hdr.Typeflag = TypeDir
+	if err != nil {
+		t.Fatalf("os.Stat:1 %v", err)
+	}
+	// Force a PAX long name to be written. The name was taken from a practical example
+	// that fails and replaced ever char through numbers to anonymize the sample.
+	longName := "/0000_0000000/00000-000000000/0000_0000000/00000-0000000000000/0000_0000000/00000-0000000-00000000/0000_0000000/00000000/0000_0000000/000/0000_0000000/00000000v00/0000_0000000/000000/0000_0000000/0000000/0000_0000000/00000y-00/0000/0000/00000000/0x000000/"
+	hdr.Name = longName
+
+	hdr.Size = 0
+	var buf bytes.Buffer
+	writer := NewWriter(&buf)
+	if err := writer.WriteHeader(hdr); err != nil {
+		t.Fatal(err)
+	}
+	if err := writer.Close(); err != nil {
+		t.Fatal(err)
+	}
+	// Test that we can get a long name back out of the archive.
+	reader := NewReader(&buf)
+	hdr, err = reader.Next()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if hdr.Name != longName {
+		t.Fatal("Couldn't recover long name")
+	}
+}
+
+func TestValidTypeflagWithPAXHeader(t *testing.T) {
+	var buffer bytes.Buffer
+	tw := NewWriter(&buffer)
+
+	fileName := strings.Repeat("ab", 100)
+
+	hdr := &Header{
+		Name:     fileName,
+		Size:     4,
+		Typeflag: 0,
+	}
+	if err := tw.WriteHeader(hdr); err != nil {
+		t.Fatalf("Failed to write header: %s", err)
+	}
+	if _, err := tw.Write([]byte("fooo")); err != nil {
+		t.Fatalf("Failed to write the file's data: %s", err)
+	}
+	tw.Close()
+
+	tr := NewReader(&buffer)
+
+	for {
+		header, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatalf("Failed to read header: %s", err)
+		}
+		if header.Typeflag != 0 {
+			t.Fatalf("Typeflag should've been 0, found %d", header.Typeflag)
+		}
+	}
+}