@@ -124,7 +124,7 @@ google.golang.org/genproto                          3f1135a288c9a07e340ae8ba4cc6

 # containerd

 github.com/containerd/containerd                    c80284d4b5291a351bb471bcdabb5c1d95e7a583 # master / v1.4.0-dev

 github.com/containerd/fifo                          ff969a566b00877c63489baf6e8c35d60af6142c

-github.com/containerd/continuity                    26c1120b8d4107d2471b93ad78ef7ce1fc84c4c4

+github.com/containerd/continuity                    efbc4488d8fe1bdc16bde3b2d2990d9b3a899165

 github.com/containerd/cgroups                       44306b6a1d46985d916b48b4199f93a378af314f

 github.com/containerd/console                       8375c3424e4d7b114e8a90a4a40c8e1b40d1d4e6 # v1.0.0

 github.com/containerd/go-runc                       7016d3ce2328dd2cb1192b2076ebd565c4e8df0c

@@ -32,6 +32,7 @@ func DeviceInfo(fi os.FileInfo) (uint64, uint64, error) {

 		return 0, 0, fmt.Errorf("cannot extract device from os.FileInfo")

 	}

+	//nolint:unconvert

 	dev := uint64(sys.Rdev)

 	return uint64(unix.Major(dev)), uint64(unix.Minor(dev)), nil

 }

@@ -138,6 +138,10 @@ func (d *driver) Lstat(p string) (os.FileInfo, error) {

 	return os.Lstat(p)

 }

+func (d *driver) Readlink(p string) (string, error) {

+	return os.Readlink(p)

+}

+

 func (d *driver) Mkdir(p string, mode os.FileMode) error {

 	return os.Mkdir(p, mode)

 }

@@ -131,8 +131,3 @@ func (d *driver) LSetxattr(path string, attrMap map[string][]byte) error {

 func (d *driver) DeviceInfo(fi os.FileInfo) (maj uint64, min uint64, err error) {

 	return devices.DeviceInfo(fi)

 }

-

-// Readlink was forked on Windows to fix a Golang bug, use the "os" package here

-func (d *driver) Readlink(p string) (string, error) {

-	return os.Readlink(p)

-}

@@ -1,3 +1,5 @@

+// +build go1.13

+

 /*

    Copyright The containerd Authors.

@@ -14,12 +16,14 @@

    limitations under the License.

 */

+// Go 1.13 is the minimally supported version for Windows.

+// Earlier golang releases have bug in os.Readlink

+// (see https://github.com/golang/go/issues/30463).

+

 package driver

 import (

 	"os"

-

-	"github.com/containerd/continuity/sysx"

 )

 func (d *driver) Mknod(path string, mode os.FileMode, major, minor int) error {

@@ -35,9 +39,3 @@ func (d *driver) Lchmod(path string, mode os.FileMode) (err error) {

 	// TODO: Use Window's equivalent

 	return os.Chmod(path, mode)

 }

-

-// Readlink is forked in order to support Volume paths which are used

-// in container layers.

-func (d *driver) Readlink(p string) (string, error) {

-	return sysx.Readlink(p)

-}

@@ -117,15 +117,13 @@ func sameFile(f1, f2 *currentPath) (bool, error) {

 		// If the timestamp may have been truncated in both of the

 		// files, check content of file to determine difference

 		if t1.Nanosecond() == 0 && t2.Nanosecond() == 0 {

-			var eq bool

 			if (f1.f.Mode() & os.ModeSymlink) == os.ModeSymlink {

-				eq, err = compareSymlinkTarget(f1.fullPath, f2.fullPath)

-			} else if f1.f.Size() > 0 {

-				eq, err = compareFileContent(f1.fullPath, f2.fullPath)

+				return compareSymlinkTarget(f1.fullPath, f2.fullPath)

 			}

-			if err != nil || !eq {

-				return eq, err

+			if f1.f.Size() == 0 { // if file sizes are zero length, the files are the same by definition

+				return true, nil

 			}

+			return compareFileContent(f1.fullPath, f2.fullPath)

 		} else if t1.Nanosecond() != t2.Nanosecond() {

 			return false, nil

 		}

@@ -1,6 +1,6 @@

 module github.com/containerd/continuity

-go 1.11

+go 1.13

 require (

 	bazil.org/fuse v0.0.0-20160811212531-371fbbdaa898

deleted file mode 100644

@@ -1,26 +0,0 @@

-// +build !windows

-

-/*

-   Copyright The containerd Authors.

-

-   Licensed under the Apache License, Version 2.0 (the "License");

-   you may not use this file except in compliance with the License.

-   You may obtain a copy of the License at

-

-       http://www.apache.org/licenses/LICENSE-2.0

-

-   Unless required by applicable law or agreed to in writing, software

-   distributed under the License is distributed on an "AS IS" BASIS,

-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

-   See the License for the specific language governing permissions and

-   limitations under the License.

-*/

-

-package syscallx

-

-import "syscall"

-

-// Readlink returns the destination of the named symbolic link.

-func Readlink(path string, buf []byte) (n int, err error) {

-	return syscall.Readlink(path, buf)

-}

deleted file mode 100644

@@ -1,112 +0,0 @@

-/*

-   Copyright The containerd Authors.

-

-   Licensed under the Apache License, Version 2.0 (the "License");

-   you may not use this file except in compliance with the License.

-   You may obtain a copy of the License at

-

-       http://www.apache.org/licenses/LICENSE-2.0

-

-   Unless required by applicable law or agreed to in writing, software

-   distributed under the License is distributed on an "AS IS" BASIS,

-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

-   See the License for the specific language governing permissions and

-   limitations under the License.

-*/

-

-package syscallx

-

-import (

-	"syscall"

-	"unsafe"

-)

-

-type reparseDataBuffer struct {

-	ReparseTag        uint32

-	ReparseDataLength uint16

-	Reserved          uint16

-

-	// GenericReparseBuffer

-	reparseBuffer byte

-}

-

-type mountPointReparseBuffer struct {

-	SubstituteNameOffset uint16

-	SubstituteNameLength uint16

-	PrintNameOffset      uint16

-	PrintNameLength      uint16

-	PathBuffer           [1]uint16

-}

-

-type symbolicLinkReparseBuffer struct {

-	SubstituteNameOffset uint16

-	SubstituteNameLength uint16

-	PrintNameOffset      uint16

-	PrintNameLength      uint16

-	Flags                uint32

-	PathBuffer           [1]uint16

-}

-

-const (

-	_IO_REPARSE_TAG_MOUNT_POINT = 0xA0000003

-	_SYMLINK_FLAG_RELATIVE      = 1

-)

-

-// Readlink returns the destination of the named symbolic link.

-func Readlink(path string, buf []byte) (n int, err error) {

-	fd, err := syscall.CreateFile(syscall.StringToUTF16Ptr(path), syscall.GENERIC_READ, 0, nil, syscall.OPEN_EXISTING,

-		syscall.FILE_FLAG_OPEN_REPARSE_POINT|syscall.FILE_FLAG_BACKUP_SEMANTICS, 0)

-	if err != nil {

-		return -1, err

-	}

-	defer syscall.CloseHandle(fd)

-

-	rdbbuf := make([]byte, syscall.MAXIMUM_REPARSE_DATA_BUFFER_SIZE)

-	var bytesReturned uint32

-	err = syscall.DeviceIoControl(fd, syscall.FSCTL_GET_REPARSE_POINT, nil, 0, &rdbbuf[0], uint32(len(rdbbuf)), &bytesReturned, nil)

-	if err != nil {

-		return -1, err

-	}

-

-	rdb := (*reparseDataBuffer)(unsafe.Pointer(&rdbbuf[0]))

-	var s string

-	switch rdb.ReparseTag {

-	case syscall.IO_REPARSE_TAG_SYMLINK:

-		data := (*symbolicLinkReparseBuffer)(unsafe.Pointer(&rdb.reparseBuffer))

-		p := (*[0xffff]uint16)(unsafe.Pointer(&data.PathBuffer[0]))

-		s = syscall.UTF16ToString(p[data.SubstituteNameOffset/2 : (data.SubstituteNameOffset+data.SubstituteNameLength)/2])

-		if data.Flags&_SYMLINK_FLAG_RELATIVE == 0 {

-			if len(s) >= 4 && s[:4] == `\??\` {

-				s = s[4:]

-				switch {

-				case len(s) >= 2 && s[1] == ':': // \??\C:\foo\bar

-					// do nothing

-				case len(s) >= 4 && s[:4] == `UNC\`: // \??\UNC\foo\bar

-					s = `\\` + s[4:]

-				default:

-					// unexpected; do nothing

-				}

-			} else {

-				// unexpected; do nothing

-			}

-		}

-	case _IO_REPARSE_TAG_MOUNT_POINT:

-		data := (*mountPointReparseBuffer)(unsafe.Pointer(&rdb.reparseBuffer))

-		p := (*[0xffff]uint16)(unsafe.Pointer(&data.PathBuffer[0]))

-		s = syscall.UTF16ToString(p[data.SubstituteNameOffset/2 : (data.SubstituteNameOffset+data.SubstituteNameLength)/2])

-		if len(s) >= 4 && s[:4] == `\??\` { // \??\C:\foo\bar

-			if len(s) < 48 || s[:11] != `\??\Volume{` {

-				s = s[4:]

-			}

-		} else {

-			// unexpected; do nothing

-		}

-	default:

-		// the path is not a symlink or junction but another type of reparse

-		// point

-		return -1, syscall.ENOENT

-	}

-	n = copy(buf, []byte(s))

-

-	return n, nil

-}

deleted file mode 100644

@@ -1,128 +0,0 @@

-/*

-   Copyright The containerd Authors.

-

-   Licensed under the Apache License, Version 2.0 (the "License");

-   you may not use this file except in compliance with the License.

-   You may obtain a copy of the License at

-

-       http://www.apache.org/licenses/LICENSE-2.0

-

-   Unless required by applicable law or agreed to in writing, software

-   distributed under the License is distributed on an "AS IS" BASIS,

-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

-   See the License for the specific language governing permissions and

-   limitations under the License.

-*/

-

-package sysx

-

-import (

-	"os"

-	"path/filepath"

-

-	"github.com/containerd/continuity/syscallx"

-)

-

-// Readlink returns the destination of the named symbolic link.

-// If there is an error, it will be of type *PathError.

-func Readlink(name string) (string, error) {

-	for len := 128; ; len *= 2 {

-		b := make([]byte, len)

-		n, e := fixCount(syscallx.Readlink(fixLongPath(name), b))

-		if e != nil {

-			return "", &os.PathError{Op: "readlink", Path: name, Err: e}

-		}

-		if n < len {

-			return string(b[0:n]), nil

-		}

-	}

-}

-

-// Many functions in package syscall return a count of -1 instead of 0.

-// Using fixCount(call()) instead of call() corrects the count.

-func fixCount(n int, err error) (int, error) {

-	if n < 0 {

-		n = 0

-	}

-	return n, err

-}

-

-// fixLongPath returns the extended-length (\\?\-prefixed) form of

-// path when needed, in order to avoid the default 260 character file

-// path limit imposed by Windows. If path is not easily converted to

-// the extended-length form (for example, if path is a relative path

-// or contains .. elements), or is short enough, fixLongPath returns

-// path unmodified.

-//

-// See https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath

-func fixLongPath(path string) string {

-	// Do nothing (and don't allocate) if the path is "short".

-	// Empirically (at least on the Windows Server 2013 builder),

-	// the kernel is arbitrarily okay with < 248 bytes. That

-	// matches what the docs above say:

-	// "When using an API to create a directory, the specified

-	// path cannot be so long that you cannot append an 8.3 file

-	// name (that is, the directory name cannot exceed MAX_PATH

-	// minus 12)." Since MAX_PATH is 260, 260 - 12 = 248.

-	//

-	// The MSDN docs appear to say that a normal path that is 248 bytes long

-	// will work; empirically the path must be less then 248 bytes long.

-	if len(path) < 248 {

-		// Don't fix. (This is how Go 1.7 and earlier worked,

-		// not automatically generating the \\?\ form)

-		return path

-	}

-

-	// The extended form begins with \\?\, as in

-	// \\?\c:\windows\foo.txt or \\?\UNC\server\share\foo.txt.

-	// The extended form disables evaluation of . and .. path

-	// elements and disables the interpretation of / as equivalent

-	// to \. The conversion here rewrites / to \ and elides

-	// . elements as well as trailing or duplicate separators. For

-	// simplicity it avoids the conversion entirely for relative

-	// paths or paths containing .. elements. For now,

-	// \\server\share paths are not converted to

-	// \\?\UNC\server\share paths because the rules for doing so

-	// are less well-specified.

-	if len(path) >= 2 && path[:2] == `\\` {

-		// Don't canonicalize UNC paths.

-		return path

-	}

-	if !filepath.IsAbs(path) {

-		// Relative path

-		return path

-	}

-

-	const prefix = `\\?`

-

-	pathbuf := make([]byte, len(prefix)+len(path)+len(`\`))

-	copy(pathbuf, prefix)

-	n := len(path)

-	r, w := 0, len(prefix)

-	for r < n {

-		switch {

-		case os.IsPathSeparator(path[r]):

-			// empty block

-			r++

-		case path[r] == '.' && (r+1 == n || os.IsPathSeparator(path[r+1])):

-			// /./

-			r++

-		case r+1 < n && path[r] == '.' && path[r+1] == '.' && (r+2 == n || os.IsPathSeparator(path[r+2])):

-			// /../ is currently unhandled

-			return path

-		default:

-			pathbuf[w] = '\\'

-			w++

-			for ; r < n && !os.IsPathSeparator(path[r]); r++ {

-				pathbuf[w] = path[r]

-				w++

-			}

-		}

-	}

-	// A drive's root directory needs a trailing \

-	if w == len(`\\?\c:`) {

-		pathbuf[w] = '\\'

-		w++

-	}

-	return string(pathbuf[:w])

-}

@@ -20,7 +20,6 @@ package sysx

 import (

 	"bytes"

-	"syscall"

 	"golang.org/x/sys/unix"

 )

@@ -66,60 +65,53 @@ func LGetxattr(path, attr string) ([]byte, error) {

 	return getxattrAll(path, attr, unix.Lgetxattr)

 }

-const defaultXattrBufferSize = 5

+const defaultXattrBufferSize = 128

 type listxattrFunc func(path string, dest []byte) (int, error)

 func listxattrAll(path string, listFunc listxattrFunc) ([]string, error) {

-	var p []byte // nil on first execution

-

-	for {

-		n, err := listFunc(path, p) // first call gets buffer size.

+	buf := make([]byte, defaultXattrBufferSize)

+	n, err := listFunc(path, buf)

+	for err == unix.ERANGE {

+		// Buffer too small, use zero-sized buffer to get the actual size

+		n, err = listFunc(path, []byte{})

 		if err != nil {

 			return nil, err

 		}

+		buf = make([]byte, n)

+		n, err = listFunc(path, buf)

+	}

+	if err != nil {

+		return nil, err

+	}

-		if n > len(p) {

-			p = make([]byte, n)

-			continue

-		}

-

-		p = p[:n]

-

-		ps := bytes.Split(bytes.TrimSuffix(p, []byte{0}), []byte{0})

-		var entries []string

-		for _, p := range ps {

-			s := string(p)

-			if s != "" {

-				entries = append(entries, s)

-			}

+	ps := bytes.Split(bytes.TrimSuffix(buf[:n], []byte{0}), []byte{0})

+	var entries []string

+	for _, p := range ps {

+		if len(p) > 0 {

+			entries = append(entries, string(p))

 		}

-

-		return entries, nil

 	}

+

+	return entries, nil

 }

 type getxattrFunc func(string, string, []byte) (int, error)

 func getxattrAll(path, attr string, getFunc getxattrFunc) ([]byte, error) {

-	p := make([]byte, defaultXattrBufferSize)

-	for {

-		n, err := getFunc(path, attr, p)

+	buf := make([]byte, defaultXattrBufferSize)

+	n, err := getFunc(path, attr, buf)

+	for err == unix.ERANGE {

+		// Buffer too small, use zero-sized buffer to get the actual size

+		n, err = getFunc(path, attr, []byte{})

 		if err != nil {

-			if errno, ok := err.(syscall.Errno); ok && errno == syscall.ERANGE {

-				p = make([]byte, len(p)*2) // this can't be ideal.

-				continue                   // try again!

-			}

-

 			return nil, err

 		}

-

-		// realloc to correct size and repeat

-		if n > len(p) {

-			p = make([]byte, n)

-			continue

-		}

-

-		return p[:n], nil

+		buf = make([]byte, n)

+		n, err = getFunc(path, attr, buf)

+	}

+	if err != nil {

+		return nil, err

 	}

+	return buf[:n], nil

 }

@@ -23,7 +23,7 @@ import (

 	"runtime"

 )

-var unsupported = errors.New("extended attributes unsupported on " + runtime.GOOS)

+var errUnsupported = errors.New("extended attributes unsupported on " + runtime.GOOS)

 // Listxattr calls syscall listxattr and reads all content

 // and returns a string array

@@ -33,17 +33,17 @@ func Listxattr(path string) ([]string, error) {

 // Removexattr calls syscall removexattr

 func Removexattr(path string, attr string) (err error) {

-	return unsupported

+	return errUnsupported

 }

 // Setxattr calls syscall setxattr

 func Setxattr(path string, attr string, data []byte, flags int) (err error) {

-	return unsupported

+	return errUnsupported

 }

 // Getxattr calls syscall getxattr

 func Getxattr(path, attr string) ([]byte, error) {

-	return []byte{}, unsupported

+	return []byte{}, errUnsupported

 }

 // LListxattr lists xattrs, not following symlinks

@@ -53,12 +53,12 @@ func LListxattr(path string) ([]string, error) {

 // LRemovexattr removes an xattr, not following symlinks

 func LRemovexattr(path string, attr string) (err error) {

-	return unsupported

+	return errUnsupported

 }

 // LSetxattr sets an xattr, not following symlinks

 func LSetxattr(path string, attr string, data []byte, flags int) (err error) {

-	return unsupported

+	return errUnsupported

 }

 // LGetxattr gets an xattr, not following symlinks