Golang system.Umask函数代码示例

// applyLayer is the entry-point for docker-applylayer on re-exec. This is not
// used on Windows as it does not support chroot, hence no point sandboxing
// through chroot and rexec.
func applyLayer() {

	var (
		tmpDir  string
		err     error
		options *archive.TarOptions
	)
	runtime.LockOSThread()
	flag.Parse()

	inUserns := rsystem.RunningInUserNS()
	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)
	}

	if err := json.Unmarshal([]byte(os.Getenv("OPT")), &options); err != nil {
		fatal(err)
	}

	if inUserns {
		options.InUserNS = true
	}

	if tmpDir, err = ioutil.TempDir("/", "temp-docker-extract"); err != nil {
		fatal(err)
	}

	os.Setenv("TMPDIR", tmpDir)
	size, err := archive.UnpackLayer("/", os.Stdin, options)
	os.RemoveAll(tmpDir)
	if err != nil {
		fatal(err)
	}

	encoder := json.NewEncoder(os.Stdout)
	if err := encoder.Encode(applyLayerResponse{size}); err != nil {
		fatal(fmt.Errorf("unable to encode layerSize JSON: %s", err))
	}

	if _, err := flush(os.Stdin); err != nil {
		fatal(err)
	}

	os.Exit(0)
}

func applyLayer() {

	var (
		root   = "/"
		tmpDir = ""
		err    error
	)

	runtime.LockOSThread()
	flag.Parse()

	if runtime.GOOS != "windows" {
		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)
	}

	if tmpDir, err = ioutil.TempDir(root, "temp-docker-extract"); err != nil {
		fatal(err)
	}

	os.Setenv("TMPDIR", tmpDir)
	size, err := archive.UnpackLayer(root, os.Stdin)
	os.RemoveAll(tmpDir)
	if err != nil {
		fatal(err)
	}

	encoder := json.NewEncoder(os.Stdout)
	if err := encoder.Encode(applyLayerResponse{size}); err != nil {
		fatal(fmt.Errorf("unable to encode layerSize JSON: %s", err))
	}

	flush(os.Stdout)
	flush(os.Stdin)
	os.Exit(0)
}

// 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)
}

func TestOverlayTarUntar(t *testing.T) {
	oldmask, err := system.Umask(0)
	if err != nil {
		t.Fatal(err)
	}
	defer system.Umask(oldmask)

	src, err := ioutil.TempDir("", "docker-test-overlay-tar-src")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(src)

	setupOverlayTestDir(t, src)

	dst, err := ioutil.TempDir("", "docker-test-overlay-tar-dst")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(dst)

	options := &TarOptions{
		Compression:    Uncompressed,
		WhiteoutFormat: OverlayWhiteoutFormat,
	}
	archive, err := TarWithOptions(src, options)
	if err != nil {
		t.Fatal(err)
	}
	defer archive.Close()

	if err := Untar(archive, dst, options); err != nil {
		t.Fatal(err)
	}

	checkFileMode(t, filepath.Join(dst, "d1"), 0700|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d2"), 0750|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d3"), 0700|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d1", "f1"), 0600)
	checkFileMode(t, filepath.Join(dst, "d2", "f1"), 0660)
	checkFileMode(t, filepath.Join(dst, "d3", "f1"), os.ModeCharDevice|os.ModeDevice)

	checkOpaqueness(t, filepath.Join(dst, "d1"), "y")
	checkOpaqueness(t, filepath.Join(dst, "d2"), "y")
	checkOpaqueness(t, filepath.Join(dst, "d3"), "")
	checkOverlayWhiteout(t, filepath.Join(dst, "d3", "f1"))
}

func TestOverlayTarAUFSUntar(t *testing.T) {
	oldmask, err := system.Umask(0)
	if err != nil {
		t.Fatal(err)
	}
	defer system.Umask(oldmask)

	src, err := ioutil.TempDir("", "docker-test-overlay-tar-src")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(src)

	setupOverlayTestDir(t, src)

	dst, err := ioutil.TempDir("", "docker-test-overlay-tar-dst")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(dst)

	archive, err := TarWithOptions(src, &TarOptions{
		Compression:    Uncompressed,
		WhiteoutFormat: OverlayWhiteoutFormat,
	})
	if err != nil {
		t.Fatal(err)
	}
	defer archive.Close()

	if err := Untar(archive, dst, &TarOptions{
		Compression:    Uncompressed,
		WhiteoutFormat: AUFSWhiteoutFormat,
	}); err != nil {
		t.Fatal(err)
	}

	checkFileMode(t, filepath.Join(dst, "d1"), 0700|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d1", WhiteoutOpaqueDir), 0700)
	checkFileMode(t, filepath.Join(dst, "d2"), 0750|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d2", WhiteoutOpaqueDir), 0750)
	checkFileMode(t, filepath.Join(dst, "d3"), 0700|os.ModeDir)
	checkFileMode(t, filepath.Join(dst, "d1", "f1"), 0600)
	checkFileMode(t, filepath.Join(dst, "d2", "f1"), 0660)
	checkFileMode(t, filepath.Join(dst, "d3", WhiteoutPrefix+"f1"), 0600)
}

// do the bulk load of ApplyLayer, but allow for not calling DecompressStream
func applyLayerHandler(dest string, layer Reader, decompress bool) (int64, error) {
	dest = filepath.Clean(dest)

	// We need to be able to set any perms
	oldmask, err := system.Umask(0)
	if err != nil {
		return 0, err
	}
	defer system.Umask(oldmask) // ignore err, ErrNotSupportedPlatform

	if decompress {
		layer, err = DecompressStream(layer)
		if err != nil {
			return 0, err
		}
	}
	return UnpackLayer(dest, layer)
}

// applyLayer is the entry-point for docker-applylayer on re-exec. This is not
// used on Windows as it does not support chroot, hence no point sandboxing
// through chroot and rexec.
func applyLayer() {

	var (
		tmpDir = ""
		err    error
	)
	runtime.LockOSThread()
	flag.Parse()

	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)
	}

	if tmpDir, err = ioutil.TempDir("/", "temp-docker-extract"); err != nil {
		fatal(err)
	}

	os.Setenv("TMPDIR", tmpDir)
	size, err := archive.UnpackLayer("/", os.Stdin)
	os.RemoveAll(tmpDir)
	if err != nil {
		fatal(err)
	}

	encoder := json.NewEncoder(os.Stdout)
	if err := encoder.Encode(applyLayerResponse{size}); err != nil {
		fatal(fmt.Errorf("unable to encode layerSize JSON: %s", err))
	}

	flush(os.Stdout)
	flush(os.Stdin)
	os.Exit(0)
}

// 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
	}

	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)
		base := filepath.Base(path)

		// Prevent symlink breakout
		if !strings.HasPrefix(path, dest) {
			return breakoutError(fmt.Errorf("%q is outside of %q", path, dest))
		}

		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
					}
//.........这里部分代码省略.........