diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/dir_unix.go b/vendor/go.etcd.io/etcd/pkg/fileutil/dir_unix.go
new file mode 100644
index 0000000..58a77df
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/dir_unix.go
@@ -0,0 +1,22 @@
+// Copyright 2016 The etcd 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.
+
+// +build !windows
+
+package fileutil
+
+import "os"
+
+// OpenDir opens a directory for syncing.
+func OpenDir(path string) (*os.File, error) { return os.Open(path) }
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/dir_windows.go b/vendor/go.etcd.io/etcd/pkg/fileutil/dir_windows.go
new file mode 100644
index 0000000..c123395
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/dir_windows.go
@@ -0,0 +1,46 @@
+// Copyright 2016 The etcd 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.
+
+// +build windows
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// OpenDir opens a directory in windows with write access for syncing.
+func OpenDir(path string) (*os.File, error) {
+	fd, err := openDir(path)
+	if err != nil {
+		return nil, err
+	}
+	return os.NewFile(uintptr(fd), path), nil
+}
+
+func openDir(path string) (fd syscall.Handle, err error) {
+	if len(path) == 0 {
+		return syscall.InvalidHandle, syscall.ERROR_FILE_NOT_FOUND
+	}
+	pathp, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return syscall.InvalidHandle, err
+	}
+	access := uint32(syscall.GENERIC_READ | syscall.GENERIC_WRITE)
+	sharemode := uint32(syscall.FILE_SHARE_READ | syscall.FILE_SHARE_WRITE)
+	createmode := uint32(syscall.OPEN_EXISTING)
+	fl := uint32(syscall.FILE_FLAG_BACKUP_SEMANTICS)
+	return syscall.CreateFile(pathp, access, sharemode, nil, createmode, fl, 0)
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/doc.go b/vendor/go.etcd.io/etcd/pkg/fileutil/doc.go
new file mode 100644
index 0000000..69dde5a
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The etcd 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 fileutil implements utility functions related to files and paths.
+package fileutil
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/fileutil.go b/vendor/go.etcd.io/etcd/pkg/fileutil/fileutil.go
new file mode 100644
index 0000000..5d9fb53
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/fileutil.go
@@ -0,0 +1,104 @@
+// Copyright 2015 The etcd 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 fileutil
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+
+	"github.com/coreos/pkg/capnslog"
+)
+
+const (
+	// PrivateFileMode grants owner to read/write a file.
+	PrivateFileMode = 0600
+	// PrivateDirMode grants owner to make/remove files inside the directory.
+	PrivateDirMode = 0700
+)
+
+var plog = capnslog.NewPackageLogger("go.etcd.io/etcd", "pkg/fileutil")
+
+// IsDirWriteable checks if dir is writable by writing and removing a file
+// to dir. It returns nil if dir is writable.
+func IsDirWriteable(dir string) error {
+	f := filepath.Join(dir, ".touch")
+	if err := ioutil.WriteFile(f, []byte(""), PrivateFileMode); err != nil {
+		return err
+	}
+	return os.Remove(f)
+}
+
+// TouchDirAll is similar to os.MkdirAll. It creates directories with 0700 permission if any directory
+// does not exists. TouchDirAll also ensures the given directory is writable.
+func TouchDirAll(dir string) error {
+	// If path is already a directory, MkdirAll does nothing
+	// and returns nil.
+	err := os.MkdirAll(dir, PrivateDirMode)
+	if err != nil {
+		// if mkdirAll("a/text") and "text" is not
+		// a directory, this will return syscall.ENOTDIR
+		return err
+	}
+	return IsDirWriteable(dir)
+}
+
+// CreateDirAll is similar to TouchDirAll but returns error
+// if the deepest directory was not empty.
+func CreateDirAll(dir string) error {
+	err := TouchDirAll(dir)
+	if err == nil {
+		var ns []string
+		ns, err = ReadDir(dir)
+		if err != nil {
+			return err
+		}
+		if len(ns) != 0 {
+			err = fmt.Errorf("expected %q to be empty, got %q", dir, ns)
+		}
+	}
+	return err
+}
+
+// Exist returns true if a file or directory exists.
+func Exist(name string) bool {
+	_, err := os.Stat(name)
+	return err == nil
+}
+
+// ZeroToEnd zeros a file starting from SEEK_CUR to its SEEK_END. May temporarily
+// shorten the length of the file.
+func ZeroToEnd(f *os.File) error {
+	// TODO: support FALLOC_FL_ZERO_RANGE
+	off, err := f.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return err
+	}
+	lenf, lerr := f.Seek(0, io.SeekEnd)
+	if lerr != nil {
+		return lerr
+	}
+	if err = f.Truncate(off); err != nil {
+		return err
+	}
+	// make sure blocks remain allocated
+	if err = Preallocate(f, lenf, true); err != nil {
+		return err
+	}
+	_, err = f.Seek(off, io.SeekStart)
+	return err
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock.go
new file mode 100644
index 0000000..338627f
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock.go
@@ -0,0 +1,26 @@
+// Copyright 2016 The etcd 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 fileutil
+
+import (
+	"errors"
+	"os"
+)
+
+var (
+	ErrLocked = errors.New("fileutil: file already locked")
+)
+
+type LockedFile struct{ *os.File }
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_flock.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_flock.go
new file mode 100644
index 0000000..542550b
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_flock.go
@@ -0,0 +1,49 @@
+// Copyright 2016 The etcd 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.
+
+// +build !windows,!plan9,!solaris
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func flockTryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
+		f.Close()
+		if err == syscall.EWOULDBLOCK {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func flockLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, err
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_linux.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_linux.go
new file mode 100644
index 0000000..b0abc98
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_linux.go
@@ -0,0 +1,97 @@
+// Copyright 2016 The etcd 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.
+
+// +build linux
+
+package fileutil
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"syscall"
+)
+
+// This used to call syscall.Flock() but that call fails with EBADF on NFS.
+// An alternative is lockf() which works on NFS but that call lets a process lock
+// the same file twice. Instead, use Linux's non-standard open file descriptor
+// locks which will block if the process already holds the file lock.
+//
+// constants from /usr/include/bits/fcntl-linux.h
+const (
+	F_OFD_GETLK  = 37
+	F_OFD_SETLK  = 37
+	F_OFD_SETLKW = 38
+)
+
+var (
+	wrlck = syscall.Flock_t{
+		Type:   syscall.F_WRLCK,
+		Whence: int16(io.SeekStart),
+		Start:  0,
+		Len:    0,
+	}
+
+	linuxTryLockFile = flockTryLockFile
+	linuxLockFile    = flockLockFile
+)
+
+func init() {
+	// use open file descriptor locks if the system supports it
+	getlk := syscall.Flock_t{Type: syscall.F_RDLCK}
+	if err := syscall.FcntlFlock(0, F_OFD_GETLK, &getlk); err == nil {
+		linuxTryLockFile = ofdTryLockFile
+		linuxLockFile = ofdLockFile
+	}
+}
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return linuxTryLockFile(path, flag, perm)
+}
+
+func ofdTryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, fmt.Errorf("ofdTryLockFile failed to open %q (%v)", path, err)
+	}
+
+	flock := wrlck
+	if err = syscall.FcntlFlock(f.Fd(), F_OFD_SETLK, &flock); err != nil {
+		f.Close()
+		if err == syscall.EWOULDBLOCK {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return linuxLockFile(path, flag, perm)
+}
+
+func ofdLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, fmt.Errorf("ofdLockFile failed to open %q (%v)", path, err)
+	}
+
+	flock := wrlck
+	err = syscall.FcntlFlock(f.Fd(), F_OFD_SETLKW, &flock)
+	if err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_plan9.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_plan9.go
new file mode 100644
index 0000000..fee6a7c
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_plan9.go
@@ -0,0 +1,45 @@
+// Copyright 2015 The etcd 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 fileutil
+
+import (
+	"os"
+	"syscall"
+	"time"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	if err := os.Chmod(path, syscall.DMEXCL|PrivateFileMode); err != nil {
+		return nil, err
+	}
+	f, err := os.Open(path, flag, perm)
+	if err != nil {
+		return nil, ErrLocked
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	if err := os.Chmod(path, syscall.DMEXCL|PrivateFileMode); err != nil {
+		return nil, err
+	}
+	for {
+		f, err := os.OpenFile(path, flag, perm)
+		if err == nil {
+			return &LockedFile{f}, nil
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_solaris.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_solaris.go
new file mode 100644
index 0000000..352ca55
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_solaris.go
@@ -0,0 +1,62 @@
+// Copyright 2015 The etcd 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.
+
+// +build solaris
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Pid = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	lock.Pid = 0
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := syscall.FcntlFlock(f.Fd(), syscall.F_SETLK, &lock); err != nil {
+		f.Close()
+		if err == syscall.EAGAIN {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Pid = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.FcntlFlock(f.Fd(), syscall.F_SETLKW, &lock); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_unix.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_unix.go
new file mode 100644
index 0000000..ed01164
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_unix.go
@@ -0,0 +1,29 @@
+// Copyright 2015 The etcd 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.
+
+// +build !windows,!plan9,!solaris,!linux
+
+package fileutil
+
+import (
+	"os"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return flockTryLockFile(path, flag, perm)
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return flockLockFile(path, flag, perm)
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/lock_windows.go b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_windows.go
new file mode 100644
index 0000000..b181723
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/lock_windows.go
@@ -0,0 +1,125 @@
+// Copyright 2015 The etcd 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.
+
+// +build windows
+
+package fileutil
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+var (
+	modkernel32    = syscall.NewLazyDLL("kernel32.dll")
+	procLockFileEx = modkernel32.NewProc("LockFileEx")
+
+	errLocked = errors.New("The process cannot access the file because another process has locked a portion of the file.")
+)
+
+const (
+	// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
+	LOCKFILE_EXCLUSIVE_LOCK   = 2
+	LOCKFILE_FAIL_IMMEDIATELY = 1
+
+	// see https://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx
+	errLockViolation syscall.Errno = 0x21
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := open(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := lockFile(syscall.Handle(f.Fd()), LOCKFILE_FAIL_IMMEDIATELY); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := open(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := lockFile(syscall.Handle(f.Fd()), 0); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func open(path string, flag int, perm os.FileMode) (*os.File, error) {
+	if path == "" {
+		return nil, fmt.Errorf("cannot open empty filename")
+	}
+	var access uint32
+	switch flag {
+	case syscall.O_RDONLY:
+		access = syscall.GENERIC_READ
+	case syscall.O_WRONLY:
+		access = syscall.GENERIC_WRITE
+	case syscall.O_RDWR:
+		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
+	case syscall.O_WRONLY | syscall.O_CREAT:
+		access = syscall.GENERIC_ALL
+	default:
+		panic(fmt.Errorf("flag %v is not supported", flag))
+	}
+	fd, err := syscall.CreateFile(&(syscall.StringToUTF16(path)[0]),
+		access,
+		syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE|syscall.FILE_SHARE_DELETE,
+		nil,
+		syscall.OPEN_ALWAYS,
+		syscall.FILE_ATTRIBUTE_NORMAL,
+		0)
+	if err != nil {
+		return nil, err
+	}
+	return os.NewFile(uintptr(fd), path), nil
+}
+
+func lockFile(fd syscall.Handle, flags uint32) error {
+	var flag uint32 = LOCKFILE_EXCLUSIVE_LOCK
+	flag |= flags
+	if fd == syscall.InvalidHandle {
+		return nil
+	}
+	err := lockFileEx(fd, flag, 1, 0, &syscall.Overlapped{})
+	if err == nil {
+		return nil
+	} else if err.Error() == errLocked.Error() {
+		return ErrLocked
+	} else if err != errLockViolation {
+		return err
+	}
+	return nil
+}
+
+func lockFileEx(h syscall.Handle, flags, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
+	var reserved uint32 = 0
+	r1, _, e1 := syscall.Syscall6(procLockFileEx.Addr(), 6, uintptr(h), uintptr(flags), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return err
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate.go b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate.go
new file mode 100644
index 0000000..c747b7c
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate.go
@@ -0,0 +1,54 @@
+// Copyright 2015 The etcd 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 fileutil
+
+import (
+	"io"
+	"os"
+)
+
+// Preallocate tries to allocate the space for given
+// file. This operation is only supported on linux by a
+// few filesystems (btrfs, ext4, etc.).
+// If the operation is unsupported, no error will be returned.
+// Otherwise, the error encountered will be returned.
+func Preallocate(f *os.File, sizeInBytes int64, extendFile bool) error {
+	if sizeInBytes == 0 {
+		// fallocate will return EINVAL if length is 0; skip
+		return nil
+	}
+	if extendFile {
+		return preallocExtend(f, sizeInBytes)
+	}
+	return preallocFixed(f, sizeInBytes)
+}
+
+func preallocExtendTrunc(f *os.File, sizeInBytes int64) error {
+	curOff, err := f.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return err
+	}
+	size, err := f.Seek(sizeInBytes, io.SeekEnd)
+	if err != nil {
+		return err
+	}
+	if _, err = f.Seek(curOff, io.SeekStart); err != nil {
+		return err
+	}
+	if sizeInBytes > size {
+		return nil
+	}
+	return f.Truncate(sizeInBytes)
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_darwin.go b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_darwin.go
new file mode 100644
index 0000000..5a6dccf
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_darwin.go
@@ -0,0 +1,65 @@
+// Copyright 2016 The etcd 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.
+
+// +build darwin
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	if err := preallocFixed(f, sizeInBytes); err != nil {
+		return err
+	}
+	return preallocExtendTrunc(f, sizeInBytes)
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error {
+	// allocate all requested space or no space at all
+	// TODO: allocate contiguous space on disk with F_ALLOCATECONTIG flag
+	fstore := &syscall.Fstore_t{
+		Flags:   syscall.F_ALLOCATEALL,
+		Posmode: syscall.F_PEOFPOSMODE,
+		Length:  sizeInBytes}
+	p := unsafe.Pointer(fstore)
+	_, _, errno := syscall.Syscall(syscall.SYS_FCNTL, f.Fd(), uintptr(syscall.F_PREALLOCATE), uintptr(p))
+	if errno == 0 || errno == syscall.ENOTSUP {
+		return nil
+	}
+
+	// wrong argument to fallocate syscall
+	if errno == syscall.EINVAL {
+		// filesystem "st_blocks" are allocated in the units of
+		// "Allocation Block Size" (run "diskutil info /" command)
+		var stat syscall.Stat_t
+		syscall.Fstat(int(f.Fd()), &stat)
+
+		// syscall.Statfs_t.Bsize is "optimal transfer block size"
+		// and contains matching 4096 value when latest OS X kernel
+		// supports 4,096 KB filesystem block size
+		var statfs syscall.Statfs_t
+		syscall.Fstatfs(int(f.Fd()), &statfs)
+		blockSize := int64(statfs.Bsize)
+
+		if stat.Blocks*blockSize >= sizeInBytes {
+			// enough blocks are already allocated
+			return nil
+		}
+	}
+	return errno
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unix.go b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unix.go
new file mode 100644
index 0000000..50bd84f
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unix.go
@@ -0,0 +1,49 @@
+// Copyright 2016 The etcd 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.
+
+// +build linux
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	// use mode = 0 to change size
+	err := syscall.Fallocate(int(f.Fd()), 0, 0, sizeInBytes)
+	if err != nil {
+		errno, ok := err.(syscall.Errno)
+		// not supported; fallback
+		// fallocate EINTRs frequently in some environments; fallback
+		if ok && (errno == syscall.ENOTSUP || errno == syscall.EINTR) {
+			return preallocExtendTrunc(f, sizeInBytes)
+		}
+	}
+	return err
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error {
+	// use mode = 1 to keep size; see FALLOC_FL_KEEP_SIZE
+	err := syscall.Fallocate(int(f.Fd()), 1, 0, sizeInBytes)
+	if err != nil {
+		errno, ok := err.(syscall.Errno)
+		// treat not supported as nil error
+		if ok && errno == syscall.ENOTSUP {
+			return nil
+		}
+	}
+	return err
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unsupported.go b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unsupported.go
new file mode 100644
index 0000000..162fbc5
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/preallocate_unsupported.go
@@ -0,0 +1,25 @@
+// Copyright 2015 The etcd 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.
+
+// +build !linux,!darwin
+
+package fileutil
+
+import "os"
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	return preallocExtendTrunc(f, sizeInBytes)
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error { return nil }
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/purge.go b/vendor/go.etcd.io/etcd/pkg/fileutil/purge.go
new file mode 100644
index 0000000..fda96c3
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/purge.go
@@ -0,0 +1,88 @@
+// Copyright 2015 The etcd 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 fileutil
+
+import (
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"go.uber.org/zap"
+)
+
+func PurgeFile(lg *zap.Logger, dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error {
+	return purgeFile(lg, dirname, suffix, max, interval, stop, nil)
+}
+
+// purgeFile is the internal implementation for PurgeFile which can post purged files to purgec if non-nil.
+func purgeFile(lg *zap.Logger, dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}, purgec chan<- string) <-chan error {
+	errC := make(chan error, 1)
+	go func() {
+		for {
+			fnames, err := ReadDir(dirname)
+			if err != nil {
+				errC <- err
+				return
+			}
+			newfnames := make([]string, 0)
+			for _, fname := range fnames {
+				if strings.HasSuffix(fname, suffix) {
+					newfnames = append(newfnames, fname)
+				}
+			}
+			sort.Strings(newfnames)
+			fnames = newfnames
+			for len(newfnames) > int(max) {
+				f := filepath.Join(dirname, newfnames[0])
+				l, err := TryLockFile(f, os.O_WRONLY, PrivateFileMode)
+				if err != nil {
+					break
+				}
+				if err = os.Remove(f); err != nil {
+					errC <- err
+					return
+				}
+				if err = l.Close(); err != nil {
+					if lg != nil {
+						lg.Warn("failed to unlock/close", zap.String("path", l.Name()), zap.Error(err))
+					} else {
+						plog.Errorf("error unlocking %s when purging file (%v)", l.Name(), err)
+					}
+					errC <- err
+					return
+				}
+				if lg != nil {
+					lg.Info("purged", zap.String("path", f))
+				} else {
+					plog.Infof("purged file %s successfully", f)
+				}
+				newfnames = newfnames[1:]
+			}
+			if purgec != nil {
+				for i := 0; i < len(fnames)-len(newfnames); i++ {
+					purgec <- fnames[i]
+				}
+			}
+			select {
+			case <-time.After(interval):
+			case <-stop:
+				return
+			}
+		}
+	}()
+	return errC
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/read_dir.go b/vendor/go.etcd.io/etcd/pkg/fileutil/read_dir.go
new file mode 100644
index 0000000..2eeaa89
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/read_dir.go
@@ -0,0 +1,70 @@
+// Copyright 2018 The etcd 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 fileutil
+
+import (
+	"os"
+	"path/filepath"
+	"sort"
+)
+
+// ReadDirOp represents an read-directory operation.
+type ReadDirOp struct {
+	ext string
+}
+
+// ReadDirOption configures archiver operations.
+type ReadDirOption func(*ReadDirOp)
+
+// WithExt filters file names by their extensions.
+// (e.g. WithExt(".wal") to list only WAL files)
+func WithExt(ext string) ReadDirOption {
+	return func(op *ReadDirOp) { op.ext = ext }
+}
+
+func (op *ReadDirOp) applyOpts(opts []ReadDirOption) {
+	for _, opt := range opts {
+		opt(op)
+	}
+}
+
+// ReadDir returns the filenames in the given directory in sorted order.
+func ReadDir(d string, opts ...ReadDirOption) ([]string, error) {
+	op := &ReadDirOp{}
+	op.applyOpts(opts)
+
+	dir, err := os.Open(d)
+	if err != nil {
+		return nil, err
+	}
+	defer dir.Close()
+
+	names, err := dir.Readdirnames(-1)
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(names)
+
+	if op.ext != "" {
+		tss := make([]string, 0)
+		for _, v := range names {
+			if filepath.Ext(v) == op.ext {
+				tss = append(tss, v)
+			}
+		}
+		names = tss
+	}
+	return names, nil
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/sync.go b/vendor/go.etcd.io/etcd/pkg/fileutil/sync.go
new file mode 100644
index 0000000..54dd41f
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/sync.go
@@ -0,0 +1,29 @@
+// Copyright 2016 The etcd 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.
+
+// +build !linux,!darwin
+
+package fileutil
+
+import "os"
+
+// Fsync is a wrapper around file.Sync(). Special handling is needed on darwin platform.
+func Fsync(f *os.File) error {
+	return f.Sync()
+}
+
+// Fdatasync is a wrapper around file.Sync(). Special handling is needed on linux platform.
+func Fdatasync(f *os.File) error {
+	return f.Sync()
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/sync_darwin.go b/vendor/go.etcd.io/etcd/pkg/fileutil/sync_darwin.go
new file mode 100644
index 0000000..c2f39bf
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/sync_darwin.go
@@ -0,0 +1,40 @@
+// Copyright 2016 The etcd 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.
+
+// +build darwin
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// Fsync on HFS/OSX flushes the data on to the physical drive but the drive
+// may not write it to the persistent media for quite sometime and it may be
+// written in out-of-order sequence. Using F_FULLFSYNC ensures that the
+// physical drive's buffer will also get flushed to the media.
+func Fsync(f *os.File) error {
+	_, _, errno := syscall.Syscall(syscall.SYS_FCNTL, f.Fd(), uintptr(syscall.F_FULLFSYNC), uintptr(0))
+	if errno == 0 {
+		return nil
+	}
+	return errno
+}
+
+// Fdatasync on darwin platform invokes fcntl(F_FULLFSYNC) for actual persistence
+// on physical drive media.
+func Fdatasync(f *os.File) error {
+	return Fsync(f)
+}
diff --git a/vendor/go.etcd.io/etcd/pkg/fileutil/sync_linux.go b/vendor/go.etcd.io/etcd/pkg/fileutil/sync_linux.go
new file mode 100644
index 0000000..1bbced9
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/pkg/fileutil/sync_linux.go
@@ -0,0 +1,34 @@
+// Copyright 2016 The etcd 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.
+
+// +build linux
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// Fsync is a wrapper around file.Sync(). Special handling is needed on darwin platform.
+func Fsync(f *os.File) error {
+	return f.Sync()
+}
+
+// Fdatasync is similar to fsync(), but does not flush modified metadata
+// unless that metadata is needed in order to allow a subsequent data retrieval
+// to be correctly handled.
+func Fdatasync(f *os.File) error {
+	return syscall.Fdatasync(int(f.Fd()))
+}