Windows: chrootarchive refactor

Signed-off-by: John Howard <jhoward@microsoft.com>

chrootarchive/archive.go

@@ -9,21 +9,14 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
-	"syscall"
 
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/reexec"
+	"github.com/docker/docker/pkg/system"
 )
 
 var chrootArchiver = &archive.Archiver{Untar: Untar}
 
-func chroot(path string) error {
-	if err := syscall.Chroot(path); err != nil {
-		return err
-	}
-	return syscall.Chdir("/")
-}
-
 func untar() {
 	runtime.LockOSThread()
 	flag.Parse()
@@ -38,7 +31,20 @@ func untar() {
 	if err := chroot(flag.Arg(0)); err != nil {
 		fatal(err)
 	}
-	if err := archive.Unpack(os.Stdin, "/", options); err != nil {
+
+	// Explanation of Windows difference. Windows does not support chroot.
+	// untar() is a helper function for the command line in the format
+	// "docker docker-untar directory input". In Windows, directory will be
+	// something like <pathto>\docker-buildnnnnnnnnn. So, just use that directory
+	// directly instead.
+	//
+	// One example of where this is used is in the docker build command where the
+	// dockerfile will be unpacked to the machine on which the daemon runs.
+	rootPath := "/"
+	if runtime.GOOS == "windows" {
+		rootPath = flag.Arg(0)
+	}
+	if err := archive.Unpack(os.Stdin, rootPath, options); err != nil {
 		fatal(err)
 	}
 	// fully consume stdin in case it is zero padded
@@ -59,7 +65,7 @@ func Untar(tarArchive io.Reader, dest string, options *archive.TarOptions) error
 
 	dest = filepath.Clean(dest)
 	if _, err := os.Stat(dest); os.IsNotExist(err) {
-		if err := os.MkdirAll(dest, 0777); err != nil {
+		if err := system.MkdirAll(dest, 0777); err != nil {
 			return err
 		}
 	}

chrootarchive/archive_test.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
-	"path"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -15,6 +14,7 @@ import (
 
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/reexec"
+	"github.com/docker/docker/pkg/system"
 )
 
 func init() {
@@ -28,7 +28,7 @@ func TestChrootTarUntar(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if err := ioutil.WriteFile(filepath.Join(src, "toto"), []byte("hello toto"), 0644); err != nil {
@@ -42,7 +42,7 @@ func TestChrootTarUntar(t *testing.T) {
 		t.Fatal(err)
 	}
 	dest := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(dest, 0700); err != nil {
+	if err := system.MkdirAll(dest, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if err := Untar(stream, dest, &archive.TarOptions{ExcludePatterns: []string{"lolo"}}); err != nil {
@@ -59,7 +59,7 @@ func TestChrootUntarWithHugeExcludesList(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if err := ioutil.WriteFile(filepath.Join(src, "toto"), []byte("hello toto"), 0644); err != nil {
@@ -70,7 +70,7 @@ func TestChrootUntarWithHugeExcludesList(t *testing.T) {
 		t.Fatal(err)
 	}
 	dest := filepath.Join(tmpdir, "dest")
-	if err := os.MkdirAll(dest, 0700); err != nil {
+	if err := system.MkdirAll(dest, 0700); err != nil {
 		t.Fatal(err)
 	}
 	options := &archive.TarOptions{}
@@ -101,11 +101,11 @@ func prepareSourceDirectory(numberOfFiles int, targetPath string, makeSymLinks b
 	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 {
+		if err := ioutil.WriteFile(filepath.Join(targetPath, fileName), fileData, 0700); err != nil {
 			return 0, err
 		}
 		if makeSymLinks {
-			if err := os.Symlink(path.Join(targetPath, fileName), path.Join(targetPath, fileName+"-link")); err != nil {
+			if err := os.Symlink(filepath.Join(targetPath, fileName), filepath.Join(targetPath, fileName+"-link")); err != nil {
 				return 0, err
 			}
 		}
@@ -157,7 +157,7 @@ func TestChrootTarUntarWithSymlink(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := prepareSourceDirectory(10, src, true); err != nil {
@@ -179,7 +179,7 @@ func TestChrootCopyWithTar(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := prepareSourceDirectory(10, src, true); err != nil {
@@ -225,7 +225,7 @@ func TestChrootCopyFileWithTar(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := prepareSourceDirectory(10, src, true); err != nil {
@@ -268,7 +268,7 @@ func TestChrootUntarPath(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := prepareSourceDirectory(10, src, true); err != nil {
@@ -329,7 +329,7 @@ func TestChrootUntarEmptyArchiveFromSlowReader(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	dest := filepath.Join(tmpdir, "dest")
-	if err := os.MkdirAll(dest, 0700); err != nil {
+	if err := system.MkdirAll(dest, 0700); err != nil {
 		t.Fatal(err)
 	}
 	stream := &slowEmptyTarReader{size: 10240, chunkSize: 1024}
@@ -345,7 +345,7 @@ func TestChrootApplyEmptyArchiveFromSlowReader(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	dest := filepath.Join(tmpdir, "dest")
-	if err := os.MkdirAll(dest, 0700); err != nil {
+	if err := system.MkdirAll(dest, 0700); err != nil {
 		t.Fatal(err)
 	}
 	stream := &slowEmptyTarReader{size: 10240, chunkSize: 1024}
@@ -361,7 +361,7 @@ func TestChrootApplyDotDotFile(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 	src := filepath.Join(tmpdir, "src")
-	if err := os.MkdirAll(src, 0700); err != nil {
+	if err := system.MkdirAll(src, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if err := ioutil.WriteFile(filepath.Join(src, "..gitme"), []byte(""), 0644); err != nil {
@@ -372,7 +372,7 @@ func TestChrootApplyDotDotFile(t *testing.T) {
 		t.Fatal(err)
 	}
 	dest := filepath.Join(tmpdir, "dest")
-	if err := os.MkdirAll(dest, 0700); err != nil {
+	if err := system.MkdirAll(dest, 0700); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := ApplyLayer(dest, stream); err != nil {

chrootarchive/archive_unix.go

@@ -0,0 +1,14 @@
+// +build !windows
+
+package chrootarchive
+
+import (
+	"syscall"
+)
+
+func chroot(path string) error {
+	if err := syscall.Chroot(path); err != nil {
+		return err
+	}
+	return syscall.Chdir("/")
+}

chrootarchive/archive_windows.go

@@ -0,0 +1,6 @@
+package chrootarchive
+
+// chroot is not supported by Windows
+func chroot(path string) error {
+	return nil
+}

chrootarchive/diff.go

@@ -9,10 +9,10 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
-	"syscall"
 
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/reexec"
+	"github.com/docker/docker/pkg/system"
 )
 
 type applyLayerResponse struct {
@@ -20,23 +20,40 @@ type applyLayerResponse struct {
 }
 
 func applyLayer() {
+
+	var (
+		root   = "/"
+		tmpDir = ""
+		err    error
+	)
+
 	runtime.LockOSThread()
 	flag.Parse()
 
-	if err := chroot(flag.Arg(0)); err != nil {
+	if runtime.GOOS != "windows" {
-		fatal(err)
+		if err := chroot(flag.Arg(0)); err != nil {
+			fatal(err)
+		}
+
+		// We need to be able to set any perms
+		oldmask, err := system.Umask(0)
+		defer system.Umask(oldmask)
+		if err != nil {
+			fatal(err)
+		}
+	} else {
+		// As Windows does not support chroot or umask, we use the directory
+		// passed in which will be <pathto>\docker-buildnnnnnnnn instead of
+		// the 'chroot-root', "/"
+		root = flag.Arg(0)
 	}
 
-	// We need to be able to set any perms
+	if tmpDir, err = ioutil.TempDir(root, "temp-docker-extract"); err != nil {
-	oldmask := syscall.Umask(0)
-	defer syscall.Umask(oldmask)
-	tmpDir, err := ioutil.TempDir("/", "temp-docker-extract")
-	if err != nil {
 		fatal(err)
 	}
 
 	os.Setenv("TMPDIR", tmpDir)
-	size, err := archive.UnpackLayer("/", os.Stdin)
+	size, err := archive.UnpackLayer(root, os.Stdin)
 	os.RemoveAll(tmpDir)
 	if err != nil {
 		fatal(err)