ignore lchown error on docker cp

Docker-DCO-1.1-Signed-off-by: Victor Vieux <vieux@docker.com> (github: vieux)

api/client/commands.go

@@ -2058,7 +2058,7 @@ func (cli *DockerCli) CmdCp(args ...string) error {
 	}
 
 	if statusCode == 200 {
-		if err := archive.Untar(stream, copyData.Get("HostPath"), nil); err != nil {
+		if err := archive.Untar(stream, copyData.Get("HostPath"), &archive.TarOptions{NoLchown: true}); err != nil {
 			return err
 		}
 	}

archive/archive.go

@@ -28,6 +28,7 @@ type (
 	TarOptions    struct {
 		Includes    []string
 		Compression Compression
+		NoLchown    bool
 	}
 )
 
@@ -179,7 +180,7 @@ func addTarFile(path, name string, tw *tar.Writer) error {
 	return nil
 }
 
-func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader) error {
+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)
@@ -240,7 +241,7 @@ func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader) e
 		return fmt.Errorf("Unhandled tar header type %d\n", hdr.Typeflag)
 	}
 
-	if err := os.Lchown(path, hdr.Uid, hdr.Gid); err != nil {
+	if err := os.Lchown(path, hdr.Uid, hdr.Gid); err != nil && Lchown {
 		return err
 	}
 
@@ -415,8 +416,7 @@ func Untar(archive io.Reader, dest string, options *TarOptions) error {
 				}
 			}
 		}
-
-		if err := createTarFile(path, dest, hdr, tr); err != nil {
+		if err := createTarFile(path, dest, hdr, tr, options == nil || !options.NoLchown); err != nil {
 			return err
 		}
 

archive/archive_test.go

@@ -3,7 +3,6 @@ package archive
 import (
 	"bytes"
 	"fmt"
-	"github.com/dotcloud/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
 	"io"
 	"io/ioutil"
 	"os"
@@ -11,6 +10,8 @@ import (
 	"path"
 	"testing"
 	"time"
+
+	"github.com/dotcloud/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
 )
 
 func TestCmdStreamLargeStderr(t *testing.T) {
@@ -132,7 +133,7 @@ func TestTarUntar(t *testing.T) {
 // Failing prevents the archives from being uncompressed during ADD
 func TestTypeXGlobalHeaderDoesNotFail(t *testing.T) {
 	hdr := tar.Header{Typeflag: tar.TypeXGlobalHeader}
-	err := createTarFile("pax_global_header", "some_dir", &hdr, nil)
+	err := createTarFile("pax_global_header", "some_dir", &hdr, nil, true)
 	if err != nil {
 		t.Fatal(err)
 	}

archive/diff.go

@@ -2,13 +2,14 @@ package archive
 
 import (
 	"fmt"
-	"github.com/dotcloud/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
 	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
 	"syscall"
+
+	"github.com/dotcloud/docker/vendor/src/code.google.com/p/go/src/pkg/archive/tar"
 )
 
 // Linux device nodes are a bit weird due to backwards compat with 16 bit device nodes.
@@ -79,7 +80,7 @@ func ApplyLayer(dest string, layer ArchiveReader) error {
 					}
 					defer os.RemoveAll(aufsTempdir)
 				}
-				if err := createTarFile(filepath.Join(aufsTempdir, basename), dest, hdr, tr); err != nil {
+				if err := createTarFile(filepath.Join(aufsTempdir, basename), dest, hdr, tr, true); err != nil {
 					return err
 				}
 			}
@@ -126,7 +127,7 @@ func ApplyLayer(dest string, layer ArchiveReader) error {
 				srcData = tmpFile
 			}
 
-			if err := createTarFile(path, dest, srcHdr, srcData); err != nil {
+			if err := createTarFile(path, dest, srcHdr, srcData, true); err != nil {
 				return err
 			}