Bump golang.org/x/crypto

Bump golang.org.x/cyrpto to the latest

Signed-off-by: root <root@localhost.localdomain>
Signed-off-by: TomSweeneyRedHat <tsweeney@redhat.com>

64 files changed, 3669 insertions, 1103 deletions

diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_arm64.go b/vendor/golang.org/x/crypto/chacha20/chacha_arm64.go
index b799e440b..c474e5a80 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_arm64.go
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_arm64.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build go1.11,!gccgo,!purego
+// +build go1.11,gc,!purego
 
 package chacha20
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_arm64.s b/vendor/golang.org/x/crypto/chacha20/chacha_arm64.s
index 891481539..8fb49a13e 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_arm64.s
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_arm64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build go1.11,!gccgo,!purego
+// +build go1.11,gc,!purego
 
 #include "textflag.h"
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go b/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
index 4635307b8..3e8a609fb 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_noasm.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !arm64,!s390x,!ppc64le arm64,!go1.11 gccgo purego
+// +build !arm64,!s390x,!ppc64le arm64,!go1.11 !gc purego
 
 package chacha20
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.go b/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.go
index b79933034..2806c6325 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.go
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 package chacha20
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.s b/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.s
index 23c602164..3dad4b2fa 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.s
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.s
@@ -19,7 +19,7 @@
 // The differences in this and the original implementation are
 // due to the calling conventions and initialization of constants.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 #include "textflag.h"
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_s390x.go b/vendor/golang.org/x/crypto/chacha20/chacha_s390x.go
index a9244bdf4..a0774dde1 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_s390x.go
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_s390x.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 package chacha20
 
diff --git a/vendor/golang.org/x/crypto/chacha20/chacha_s390x.s b/vendor/golang.org/x/crypto/chacha20/chacha_s390x.s
index 89c658c41..818161189 100644
--- a/vendor/golang.org/x/crypto/chacha20/chacha_s390x.s
+++ b/vendor/golang.org/x/crypto/chacha20/chacha_s390x.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 #include "go_asm.h"
 #include "textflag.h"
diff --git a/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.go b/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.go
index 5120b779b..877b6de29 100644
--- a/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.go
+++ b/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build amd64,!gccgo,!appengine,!purego
+// +build amd64,gc,!purego
 
 package curve25519
 
diff --git a/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.s b/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.s
index 0250c8885..6c5338092 100644
--- a/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.s
+++ b/vendor/golang.org/x/crypto/curve25519/curve25519_amd64.s
@@ -5,7 +5,7 @@
 // This code was translated into a form compatible with 6a from the public
 // domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
 
-// +build amd64,!gccgo,!appengine,!purego
+// +build amd64,gc,!purego
 
 #define REDMASK51     0x0007FFFFFFFFFFFF
 
diff --git a/vendor/golang.org/x/crypto/curve25519/curve25519_noasm.go b/vendor/golang.org/x/crypto/curve25519/curve25519_noasm.go
index 047d49afc..80d3300af 100644
--- a/vendor/golang.org/x/crypto/curve25519/curve25519_noasm.go
+++ b/vendor/golang.org/x/crypto/curve25519/curve25519_noasm.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !amd64 gccgo appengine purego
+// +build !amd64 !gc purego
 
 package curve25519
 
diff --git a/vendor/golang.org/x/crypto/internal/subtle/aliasing.go b/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
index f38797bfa..281c27ef0 100644
--- a/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
+++ b/vendor/golang.org/x/crypto/internal/subtle/aliasing.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !appengine
+// +build !purego
 
 // Package subtle implements functions that are often useful in cryptographic
 // code but require careful thought to use correctly.
diff --git a/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go b/vendor/golang.org/x/crypto/internal/subtle/aliasing_purego.go
index 0cc4a8a64..e20a29659 100644
--- a/vendor/golang.org/x/crypto/internal/subtle/aliasing_appengine.go
+++ b/vendor/golang.org/x/crypto/internal/subtle/aliasing_purego.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build appengine
+// +build purego
 
 // Package subtle implements functions that are often useful in cryptographic
 // code but require careful thought to use correctly.
diff --git a/vendor/golang.org/x/crypto/poly1305/mac_noasm.go b/vendor/golang.org/x/crypto/poly1305/mac_noasm.go
index d118f30ed..af6c94f92 100644
--- a/vendor/golang.org/x/crypto/poly1305/mac_noasm.go
+++ b/vendor/golang.org/x/crypto/poly1305/mac_noasm.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !amd64,!ppc64le,!s390x gccgo purego
+// +build !amd64,!ppc64le,!s390x !gc purego
 
 package poly1305
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_amd64.go b/vendor/golang.org/x/crypto/poly1305/sum_amd64.go
index 99e5a1d50..cf3a69ed3 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_amd64.go
+++ b/vendor/golang.org/x/crypto/poly1305/sum_amd64.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 package poly1305
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_amd64.s b/vendor/golang.org/x/crypto/poly1305/sum_amd64.s
index 8d394a212..2cb037314 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_amd64.s
+++ b/vendor/golang.org/x/crypto/poly1305/sum_amd64.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 #include "textflag.h"
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go b/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go
index 2e7a120b1..cb4b7185d 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go
+++ b/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 package poly1305
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s b/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s
index 4e0281387..5cd7494b2 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s
+++ b/vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 #include "textflag.h"
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_s390x.go b/vendor/golang.org/x/crypto/poly1305/sum_s390x.go
index 958fedc07..188a665e1 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_s390x.go
+++ b/vendor/golang.org/x/crypto/poly1305/sum_s390x.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 package poly1305
 
diff --git a/vendor/golang.org/x/crypto/poly1305/sum_s390x.s b/vendor/golang.org/x/crypto/poly1305/sum_s390x.s
index 0fa9ee6e0..bdd882c60 100644
--- a/vendor/golang.org/x/crypto/poly1305/sum_s390x.s
+++ b/vendor/golang.org/x/crypto/poly1305/sum_s390x.s
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !gccgo,!purego
+// +build gc,!purego
 
 #include "textflag.h"
 
diff --git a/vendor/golang.org/x/crypto/ssh/client_auth.go b/vendor/golang.org/x/crypto/ssh/client_auth.go
index f3265655e..c611aeb68 100644
--- a/vendor/golang.org/x/crypto/ssh/client_auth.go
+++ b/vendor/golang.org/x/crypto/ssh/client_auth.go
@@ -471,7 +471,7 @@ func (cb KeyboardInteractiveChallenge) auth(session []byte, user string, c packe
 		}
 
 		if len(answers) != len(prompts) {
-			return authFailure, nil, errors.New("ssh: not enough answers from keyboard-interactive callback")
+			return authFailure, nil, fmt.Errorf("ssh: incorrect number of answers from keyboard-interactive callback %d (expected %d)", len(answers), len(prompts))
 		}
 		responseLength := 1 + 4
 		for _, a := range answers {
diff --git a/vendor/golang.org/x/crypto/ssh/kex.go b/vendor/golang.org/x/crypto/ssh/kex.go
index 7eedb209f..766e92939 100644
--- a/vendor/golang.org/x/crypto/ssh/kex.go
+++ b/vendor/golang.org/x/crypto/ssh/kex.go
@@ -557,8 +557,6 @@ type dhGEXSHA struct {
 	hashFunc crypto.Hash
 }
 
-const numMRTests = 64
-
 const (
 	dhGroupExchangeMinimumBits   = 2048
 	dhGroupExchangePreferredBits = 2048
@@ -602,15 +600,8 @@ func (gex dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshake
 	gex.p = kexDHGexGroup.P
 	gex.g = kexDHGexGroup.G
 
-	// Check if p is safe by verifing that p and (p-1)/2 are primes
-	one := big.NewInt(1)
-	var pHalf = &big.Int{}
-	pHalf.Rsh(gex.p, 1)
-	if !gex.p.ProbablyPrime(numMRTests) || !pHalf.ProbablyPrime(numMRTests) {
-		return nil, fmt.Errorf("ssh: server provided gex p is not safe")
-	}
-
 	// Check if g is safe by verifing that g > 1 and g < p - 1
+	one := big.NewInt(1)
 	var pMinusOne = &big.Int{}
 	pMinusOne.Sub(gex.p, one)
 	if gex.g.Cmp(one) != 1 && gex.g.Cmp(pMinusOne) != -1 {
@@ -618,6 +609,8 @@ func (gex dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshake
 	}
 
 	// Send GexInit
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
 	x, err := rand.Int(randSource, pHalf)
 	if err != nil {
 		return nil, err
diff --git a/vendor/golang.org/x/crypto/ssh/server.go b/vendor/golang.org/x/crypto/ssh/server.go
index 7d42a8c88..b6911e830 100644
--- a/vendor/golang.org/x/crypto/ssh/server.go
+++ b/vendor/golang.org/x/crypto/ssh/server.go
@@ -572,6 +572,10 @@ userAuthLoop:
 				perms = candidate.perms
 			}
 		case "gssapi-with-mic":
+			if config.GSSAPIWithMICConfig == nil {
+				authErr = errors.New("ssh: gssapi-with-mic auth not configured")
+				break
+			}
 			gssapiConfig := config.GSSAPIWithMICConfig
 			userAuthRequestGSSAPI, err := parseGSSAPIPayload(userAuthReq.Payload)
 			if err != nil {
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/terminal.go b/vendor/golang.org/x/crypto/ssh/terminal/terminal.go
index 2ffb97bfb..a4d1919a9 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/terminal.go
+++ b/vendor/golang.org/x/crypto/ssh/terminal/terminal.go
@@ -2,986 +2,75 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Deprecated: this package moved to golang.org/x/term.
 package terminal
 
 import (
-	"bytes"
 	"io"
-	"runtime"
-	"strconv"
-	"sync"
-	"unicode/utf8"
+
+	"golang.org/x/term"
 )
 
 // EscapeCodes contains escape sequences that can be written to the terminal in
 // order to achieve different styles of text.
-type EscapeCodes struct {
-	// Foreground colors
-	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
-
-	// Reset all attributes
-	Reset []byte
-}
-
-var vt100EscapeCodes = EscapeCodes{
-	Black:   []byte{keyEscape, '[', '3', '0', 'm'},
-	Red:     []byte{keyEscape, '[', '3', '1', 'm'},
-	Green:   []byte{keyEscape, '[', '3', '2', 'm'},
-	Yellow:  []byte{keyEscape, '[', '3', '3', 'm'},
-	Blue:    []byte{keyEscape, '[', '3', '4', 'm'},
-	Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
-	Cyan:    []byte{keyEscape, '[', '3', '6', 'm'},
-	White:   []byte{keyEscape, '[', '3', '7', 'm'},
-
-	Reset: []byte{keyEscape, '[', '0', 'm'},
-}
+type EscapeCodes = term.EscapeCodes
 
 // Terminal contains the state for running a VT100 terminal that is capable of
 // reading lines of input.
-type Terminal struct {
-	// AutoCompleteCallback, if non-null, is called for each keypress with
-	// the full input line and the current position of the cursor (in
-	// bytes, as an index into |line|). If it returns ok=false, the key
-	// press is processed normally. Otherwise it returns a replacement line
-	// and the new cursor position.
-	AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
-
-	// Escape contains a pointer to the escape codes for this terminal.
-	// It's always a valid pointer, although the escape codes themselves
-	// may be empty if the terminal doesn't support them.
-	Escape *EscapeCodes
-
-	// lock protects the terminal and the state in this object from
-	// concurrent processing of a key press and a Write() call.
-	lock sync.Mutex
-
-	c      io.ReadWriter
-	prompt []rune
-
-	// line is the current line being entered.
-	line []rune
-	// pos is the logical position of the cursor in line
-	pos int
-	// echo is true if local echo is enabled
-	echo bool
-	// pasteActive is true iff there is a bracketed paste operation in
-	// progress.
-	pasteActive bool
-
-	// cursorX contains the current X value of the cursor where the left
-	// edge is 0. cursorY contains the row number where the first row of
-	// the current line is 0.
-	cursorX, cursorY int
-	// maxLine is the greatest value of cursorY so far.
-	maxLine int
-
-	termWidth, termHeight int
-
-	// outBuf contains the terminal data to be sent.
-	outBuf []byte
-	// remainder contains the remainder of any partial key sequences after
-	// a read. It aliases into inBuf.
-	remainder []byte
-	inBuf     [256]byte
-
-	// history contains previously entered commands so that they can be
-	// accessed with the up and down keys.
-	history stRingBuffer
-	// historyIndex stores the currently accessed history entry, where zero
-	// means the immediately previous entry.
-	historyIndex int
-	// When navigating up and down the history it's possible to return to
-	// the incomplete, initial line. That value is stored in
-	// historyPending.
-	historyPending string
-}
+type Terminal = term.Terminal
 
 // NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
 // a local terminal, that terminal must first have been put into raw mode.
 // prompt is a string that is written at the start of each input line (i.e.
 // "> ").
 func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
-	return &Terminal{
-		Escape:       &vt100EscapeCodes,
-		c:            c,
-		prompt:       []rune(prompt),
-		termWidth:    80,
-		termHeight:   24,
-		echo:         true,
-		historyIndex: -1,
-	}
-}
-
-const (
-	keyCtrlC     = 3
-	keyCtrlD     = 4
-	keyCtrlU     = 21
-	keyEnter     = '\r'
-	keyEscape    = 27
-	keyBackspace = 127
-	keyUnknown   = 0xd800 /* UTF-16 surrogate area */ + iota
-	keyUp
-	keyDown
-	keyLeft
-	keyRight
-	keyAltLeft
-	keyAltRight
-	keyHome
-	keyEnd
-	keyDeleteWord
-	keyDeleteLine
-	keyClearScreen
-	keyPasteStart
-	keyPasteEnd
-)
-
-var (
-	crlf       = []byte{'\r', '\n'}
-	pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
-	pasteEnd   = []byte{keyEscape, '[', '2', '0', '1', '~'}
-)
-
-// bytesToKey tries to parse a key sequence from b. If successful, it returns
-// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
-func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
-	if len(b) == 0 {
-		return utf8.RuneError, nil
-	}
-
-	if !pasteActive {
-		switch b[0] {
-		case 1: // ^A
-			return keyHome, b[1:]
-		case 2: // ^B
-			return keyLeft, b[1:]
-		case 5: // ^E
-			return keyEnd, b[1:]
-		case 6: // ^F
-			return keyRight, b[1:]
-		case 8: // ^H
-			return keyBackspace, b[1:]
-		case 11: // ^K
-			return keyDeleteLine, b[1:]
-		case 12: // ^L
-			return keyClearScreen, b[1:]
-		case 23: // ^W
-			return keyDeleteWord, b[1:]
-		case 14: // ^N
-			return keyDown, b[1:]
-		case 16: // ^P
-			return keyUp, b[1:]
-		}
-	}
-
-	if b[0] != keyEscape {
-		if !utf8.FullRune(b) {
-			return utf8.RuneError, b
-		}
-		r, l := utf8.DecodeRune(b)
-		return r, b[l:]
-	}
-
-	if !pasteActive && len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
-		switch b[2] {
-		case 'A':
-			return keyUp, b[3:]
-		case 'B':
-			return keyDown, b[3:]
-		case 'C':
-			return keyRight, b[3:]
-		case 'D':
-			return keyLeft, b[3:]
-		case 'H':
-			return keyHome, b[3:]
-		case 'F':
-			return keyEnd, b[3:]
-		}
-	}
-
-	if !pasteActive && len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
-		switch b[5] {
-		case 'C':
-			return keyAltRight, b[6:]
-		case 'D':
-			return keyAltLeft, b[6:]
-		}
-	}
-
-	if !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
-		return keyPasteStart, b[6:]
-	}
-
-	if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
-		return keyPasteEnd, b[6:]
-	}
-
-	// If we get here then we have a key that we don't recognise, or a
-	// partial sequence. It's not clear how one should find the end of a
-	// sequence without knowing them all, but it seems that [a-zA-Z~] only
-	// appears at the end of a sequence.
-	for i, c := range b[0:] {
-		if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '~' {
-			return keyUnknown, b[i+1:]
-		}
-	}
-
-	return utf8.RuneError, b
-}
-
-// queue appends data to the end of t.outBuf
-func (t *Terminal) queue(data []rune) {
-	t.outBuf = append(t.outBuf, []byte(string(data))...)
-}
-
-var eraseUnderCursor = []rune{' ', keyEscape, '[', 'D'}
-var space = []rune{' '}
-
-func isPrintable(key rune) bool {
-	isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
-	return key >= 32 && !isInSurrogateArea
-}
-
-// moveCursorToPos appends data to t.outBuf which will move the cursor to the
-// given, logical position in the text.
-func (t *Terminal) moveCursorToPos(pos int) {
-	if !t.echo {
-		return
-	}
-
-	x := visualLength(t.prompt) + pos
-	y := x / t.termWidth
-	x = x % t.termWidth
-
-	up := 0
-	if y < t.cursorY {
-		up = t.cursorY - y
-	}
-
-	down := 0
-	if y > t.cursorY {
-		down = y - t.cursorY
-	}
-
-	left := 0
-	if x < t.cursorX {
-		left = t.cursorX - x
-	}
-
-	right := 0
-	if x > t.cursorX {
-		right = x - t.cursorX
-	}
-
-	t.cursorX = x
-	t.cursorY = y
-	t.move(up, down, left, right)
-}
-
-func (t *Terminal) move(up, down, left, right int) {
-	m := []rune{}
-
-	// 1 unit up can be expressed as ^[[A or ^[A
-	// 5 units up can be expressed as ^[[5A
-
-	if up == 1 {
-		m = append(m, keyEscape, '[', 'A')
-	} else if up > 1 {
-		m = append(m, keyEscape, '[')
-		m = append(m, []rune(strconv.Itoa(up))...)
-		m = append(m, 'A')
-	}
-
-	if down == 1 {
-		m = append(m, keyEscape, '[', 'B')
-	} else if down > 1 {
-		m = append(m, keyEscape, '[')
-		m = append(m, []rune(strconv.Itoa(down))...)
-		m = append(m, 'B')
-	}
-
-	if right == 1 {
-		m = append(m, keyEscape, '[', 'C')
-	} else if right > 1 {
-		m = append(m, keyEscape, '[')
-		m = append(m, []rune(strconv.Itoa(right))...)
-		m = append(m, 'C')
-	}
-
-	if left == 1 {
-		m = append(m, keyEscape, '[', 'D')
-	} else if left > 1 {
-		m = append(m, keyEscape, '[')
-		m = append(m, []rune(strconv.Itoa(left))...)
-		m = append(m, 'D')
-	}
-
-	t.queue(m)
-}
-
-func (t *Terminal) clearLineToRight() {
-	op := []rune{keyEscape, '[', 'K'}
-	t.queue(op)
-}
-
-const maxLineLength = 4096
-
-func (t *Terminal) setLine(newLine []rune, newPos int) {
-	if t.echo {
-		t.moveCursorToPos(0)
-		t.writeLine(newLine)
-		for i := len(newLine); i < len(t.line); i++ {
-			t.writeLine(space)
-		}
-		t.moveCursorToPos(newPos)
-	}
-	t.line = newLine
-	t.pos = newPos
-}
-
-func (t *Terminal) advanceCursor(places int) {
-	t.cursorX += places
-	t.cursorY += t.cursorX / t.termWidth
-	if t.cursorY > t.maxLine {
-		t.maxLine = t.cursorY
-	}
-	t.cursorX = t.cursorX % t.termWidth
-
-	if places > 0 && t.cursorX == 0 {
-		// Normally terminals will advance the current position
-		// when writing a character. But that doesn't happen
-		// for the last character in a line. However, when
-		// writing a character (except a new line) that causes
-		// a line wrap, the position will be advanced two
-		// places.
-		//
-		// So, if we are stopping at the end of a line, we
-		// need to write a newline so that our cursor can be
-		// advanced to the next line.
-		t.outBuf = append(t.outBuf, '\r', '\n')
-	}
-}
-
-func (t *Terminal) eraseNPreviousChars(n int) {
-	if n == 0 {
-		return
-	}
-
-	if t.pos < n {
-		n = t.pos
-	}
-	t.pos -= n
-	t.moveCursorToPos(t.pos)
-
-	copy(t.line[t.pos:], t.line[n+t.pos:])
-	t.line = t.line[:len(t.line)-n]
-	if t.echo {
-		t.writeLine(t.line[t.pos:])
-		for i := 0; i < n; i++ {
-			t.queue(space)
-		}
-		t.advanceCursor(n)
-		t.moveCursorToPos(t.pos)
-	}
-}
-
-// countToLeftWord returns then number of characters from the cursor to the
-// start of the previous word.
-func (t *Terminal) countToLeftWord() int {
-	if t.pos == 0 {
-		return 0
-	}
-
-	pos := t.pos - 1
-	for pos > 0 {
-		if t.line[pos] != ' ' {
-			break
-		}
-		pos--
-	}
-	for pos > 0 {
-		if t.line[pos] == ' ' {
-			pos++
-			break
-		}
-		pos--
-	}
-
-	return t.pos - pos
-}
-
-// countToRightWord returns then number of characters from the cursor to the
-// start of the next word.
-func (t *Terminal) countToRightWord() int {
-	pos := t.pos
-	for pos < len(t.line) {
-		if t.line[pos] == ' ' {
-			break
-		}
-		pos++
-	}
-	for pos < len(t.line) {
-		if t.line[pos] != ' ' {
-			break
-		}
-		pos++
-	}
-	return pos - t.pos
-}
-
-// visualLength returns the number of visible glyphs in s.
-func visualLength(runes []rune) int {
-	inEscapeSeq := false
-	length := 0
-
-	for _, r := range runes {
-		switch {
-		case inEscapeSeq:
-			if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
-				inEscapeSeq = false
-			}
-		case r == '\x1b':
-			inEscapeSeq = true
-		default:
-			length++
-		}
-	}
-
-	return length
-}
-
-// handleKey processes the given key and, optionally, returns a line of text
-// that the user has entered.
-func (t *Terminal) handleKey(key rune) (line string, ok bool) {
-	if t.pasteActive && key != keyEnter {
-		t.addKeyToLine(key)
-		return
-	}
-
-	switch key {
-	case keyBackspace:
-		if t.pos == 0 {
-			return
-		}
-		t.eraseNPreviousChars(1)
-	case keyAltLeft:
-		// move left by a word.
-		t.pos -= t.countToLeftWord()
-		t.moveCursorToPos(t.pos)
-	case keyAltRight:
-		// move right by a word.
-		t.pos += t.countToRightWord()
-		t.moveCursorToPos(t.pos)
-	case keyLeft:
-		if t.pos == 0 {
-			return
-		}
-		t.pos--
-		t.moveCursorToPos(t.pos)
-	case keyRight:
-		if t.pos == len(t.line) {
-			return
-		}
-		t.pos++
-		t.moveCursorToPos(t.pos)
-	case keyHome:
-		if t.pos == 0 {
-			return
-		}
-		t.pos = 0
-		t.moveCursorToPos(t.pos)
-	case keyEnd:
-		if t.pos == len(t.line) {
-			return
-		}
-		t.pos = len(t.line)
-		t.moveCursorToPos(t.pos)
-	case keyUp:
-		entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
-		if !ok {
-			return "", false
-		}
-		if t.historyIndex == -1 {
-			t.historyPending = string(t.line)
-		}
-		t.historyIndex++
-		runes := []rune(entry)
-		t.setLine(runes, len(runes))
-	case keyDown:
-		switch t.historyIndex {
-		case -1:
-			return
-		case 0:
-			runes := []rune(t.historyPending)
-			t.setLine(runes, len(runes))
-			t.historyIndex--
-		default:
-			entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
-			if ok {
-				t.historyIndex--
-				runes := []rune(entry)
-				t.setLine(runes, len(runes))
-			}
-		}
-	case keyEnter:
-		t.moveCursorToPos(len(t.line))
-		t.queue([]rune("\r\n"))
-		line = string(t.line)
-		ok = true
-		t.line = t.line[:0]
-		t.pos = 0
-		t.cursorX = 0
-		t.cursorY = 0
-		t.maxLine = 0
-	case keyDeleteWord:
-		// Delete zero or more spaces and then one or more characters.
-		t.eraseNPreviousChars(t.countToLeftWord())
-	case keyDeleteLine:
-		// Delete everything from the current cursor position to the
-		// end of line.
-		for i := t.pos; i < len(t.line); i++ {
-			t.queue(space)
-			t.advanceCursor(1)
-		}
-		t.line = t.line[:t.pos]
-		t.moveCursorToPos(t.pos)
-	case keyCtrlD:
-		// Erase the character under the current position.
-		// The EOF case when the line is empty is handled in
-		// readLine().
-		if t.pos < len(t.line) {
-			t.pos++
-			t.eraseNPreviousChars(1)
-		}
-	case keyCtrlU:
-		t.eraseNPreviousChars(t.pos)
-	case keyClearScreen:
-		// Erases the screen and moves the cursor to the home position.
-		t.queue([]rune("\x1b[2J\x1b[H"))
-		t.queue(t.prompt)
-		t.cursorX, t.cursorY = 0, 0
-		t.advanceCursor(visualLength(t.prompt))
-		t.setLine(t.line, t.pos)
-	default:
-		if t.AutoCompleteCallback != nil {
-			prefix := string(t.line[:t.pos])
-			suffix := string(t.line[t.pos:])
-
-			t.lock.Unlock()
-			newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
-			t.lock.Lock()
-
-			if completeOk {
-				t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
-				return
-			}
-		}
-		if !isPrintable(key) {
-			return
-		}
-		if len(t.line) == maxLineLength {
-			return
-		}
-		t.addKeyToLine(key)
-	}
-	return
-}
-
-// addKeyToLine inserts the given key at the current position in the current
-// line.
-func (t *Terminal) addKeyToLine(key rune) {
-	if len(t.line) == cap(t.line) {
-		newLine := make([]rune, len(t.line), 2*(1+len(t.line)))
-		copy(newLine, t.line)
-		t.line = newLine
-	}
-	t.line = t.line[:len(t.line)+1]
-	copy(t.line[t.pos+1:], t.line[t.pos:])
-	t.line[t.pos] = key
-	if t.echo {
-		t.writeLine(t.line[t.pos:])
-	}
-	t.pos++
-	t.moveCursorToPos(t.pos)
-}
-
-func (t *Terminal) writeLine(line []rune) {
-	for len(line) != 0 {
-		remainingOnLine := t.termWidth - t.cursorX
-		todo := len(line)
-		if todo > remainingOnLine {
-			todo = remainingOnLine
-		}
-		t.queue(line[:todo])
-		t.advanceCursor(visualLength(line[:todo]))
-		line = line[todo:]
-	}
-}
-
-// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
-func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
-	for len(buf) > 0 {
-		i := bytes.IndexByte(buf, '\n')
-		todo := len(buf)
-		if i >= 0 {
-			todo = i
-		}
-
-		var nn int
-		nn, err = w.Write(buf[:todo])
-		n += nn
-		if err != nil {
-			return n, err
-		}
-		buf = buf[todo:]
-
-		if i >= 0 {
-			if _, err = w.Write(crlf); err != nil {
-				return n, err
-			}
-			n++
-			buf = buf[1:]
-		}
-	}
-
-	return n, nil
-}
-
-func (t *Terminal) Write(buf []byte) (n int, err error) {
-	t.lock.Lock()
-	defer t.lock.Unlock()
-
-	if t.cursorX == 0 && t.cursorY == 0 {
-		// This is the easy case: there's nothing on the screen that we
-		// have to move out of the way.
-		return writeWithCRLF(t.c, buf)
-	}
-
-	// We have a prompt and possibly user input on the screen. We
-	// have to clear it first.
-	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
-	t.cursorX = 0
-	t.clearLineToRight()
-
-	for t.cursorY > 0 {
-		t.move(1 /* up */, 0, 0, 0)
-		t.cursorY--
-		t.clearLineToRight()
-	}
-
-	if _, err = t.c.Write(t.outBuf); err != nil {
-		return
-	}
-	t.outBuf = t.outBuf[:0]
-
-	if n, err = writeWithCRLF(t.c, buf); err != nil {
-		return
-	}
-
-	t.writeLine(t.prompt)
-	if t.echo {
-		t.writeLine(t.line)
-	}
-
-	t.moveCursorToPos(t.pos)
-
-	if _, err = t.c.Write(t.outBuf); err != nil {
-		return
-	}
-	t.outBuf = t.outBuf[:0]
-	return
-}
-
-// ReadPassword temporarily changes the prompt and reads a password, without
-// echo, from the terminal.
-func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
-	t.lock.Lock()
-	defer t.lock.Unlock()
-
-	oldPrompt := t.prompt
-	t.prompt = []rune(prompt)
-	t.echo = false
-
-	line, err = t.readLine()
-
-	t.prompt = oldPrompt
-	t.echo = true
-
-	return
-}
-
-// ReadLine returns a line of input from the terminal.
-func (t *Terminal) ReadLine() (line string, err error) {
-	t.lock.Lock()
-	defer t.lock.Unlock()
-
-	return t.readLine()
-}
-
-func (t *Terminal) readLine() (line string, err error) {
-	// t.lock must be held at this point
-
-	if t.cursorX == 0 && t.cursorY == 0 {
-		t.writeLine(t.prompt)
-		t.c.Write(t.outBuf)
-		t.outBuf = t.outBuf[:0]
-	}
-
-	lineIsPasted := t.pasteActive
-
-	for {
-		rest := t.remainder
-		lineOk := false
-		for !lineOk {
-			var key rune
-			key, rest = bytesToKey(rest, t.pasteActive)
-			if key == utf8.RuneError {
-				break
-			}
-			if !t.pasteActive {
-				if key == keyCtrlD {
-					if len(t.line) == 0 {
-						return "", io.EOF
-					}
-				}
-				if key == keyCtrlC {
-					return "", io.EOF
-				}
-				if key == keyPasteStart {
-					t.pasteActive = true
-					if len(t.line) == 0 {
-						lineIsPasted = true
-					}
-					continue
-				}
-			} else if key == keyPasteEnd {
-				t.pasteActive = false
-				continue
-			}
-			if !t.pasteActive {
-				lineIsPasted = false
-			}
-			line, lineOk = t.handleKey(key)
-		}
-		if len(rest) > 0 {
-			n := copy(t.inBuf[:], rest)
-			t.remainder = t.inBuf[:n]
-		} else {
-			t.remainder = nil
-		}
-		t.c.Write(t.outBuf)
-		t.outBuf = t.outBuf[:0]
-		if lineOk {
-			if t.echo {
-				t.historyIndex = -1
-				t.history.Add(line)
-			}
-			if lineIsPasted {
-				err = ErrPasteIndicator
-			}
-			return
-		}
-
-		// t.remainder is a slice at the beginning of t.inBuf
-		// containing a partial key sequence
-		readBuf := t.inBuf[len(t.remainder):]
-		var n int
-
-		t.lock.Unlock()
-		n, err = t.c.Read(readBuf)
-		t.lock.Lock()
-
-		if err != nil {
-			return
-		}
-
-		t.remainder = t.inBuf[:n+len(t.remainder)]
-	}
-}
-
-// SetPrompt sets the prompt to be used when reading subsequent lines.
-func (t *Terminal) SetPrompt(prompt string) {
-	t.lock.Lock()
-	defer t.lock.Unlock()
-
-	t.prompt = []rune(prompt)
-}
-
-func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
-	// Move cursor to column zero at the start of the line.
-	t.move(t.cursorY, 0, t.cursorX, 0)
-	t.cursorX, t.cursorY = 0, 0
-	t.clearLineToRight()
-	for t.cursorY < numPrevLines {
-		// Move down a line
-		t.move(0, 1, 0, 0)
-		t.cursorY++
-		t.clearLineToRight()
-	}
-	// Move back to beginning.
-	t.move(t.cursorY, 0, 0, 0)
-	t.cursorX, t.cursorY = 0, 0
-
-	t.queue(t.prompt)
-	t.advanceCursor(visualLength(t.prompt))
-	t.writeLine(t.line)
-	t.moveCursorToPos(t.pos)
-}
-
-func (t *Terminal) SetSize(width, height int) error {
-	t.lock.Lock()
-	defer t.lock.Unlock()
-
-	if width == 0 {
-		width = 1
-	}
-
-	oldWidth := t.termWidth
-	t.termWidth, t.termHeight = width, height
-
-	switch {
-	case width == oldWidth:
-		// If the width didn't change then nothing else needs to be
-		// done.
-		return nil
-	case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
-		// If there is nothing on current line and no prompt printed,
-		// just do nothing
-		return nil
-	case width < oldWidth:
-		// Some terminals (e.g. xterm) will truncate lines that were
-		// too long when shinking. Others, (e.g. gnome-terminal) will
-		// attempt to wrap them. For the former, repainting t.maxLine
-		// works great, but that behaviour goes badly wrong in the case
-		// of the latter because they have doubled every full line.
-
-		// We assume that we are working on a terminal that wraps lines
-		// and adjust the cursor position based on every previous line
-		// wrapping and turning into two. This causes the prompt on
-		// xterms to move upwards, which isn't great, but it avoids a
-		// huge mess with gnome-terminal.
-		if t.cursorX >= t.termWidth {
-			t.cursorX = t.termWidth - 1
-		}
-		t.cursorY *= 2
-		t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
-	case width > oldWidth:
-		// If the terminal expands then our position calculations will
-		// be wrong in the future because we think the cursor is
-		// |t.pos| chars into the string, but there will be a gap at
-		// the end of any wrapped line.
-		//
-		// But the position will actually be correct until we move, so
-		// we can move back to the beginning and repaint everything.
-		t.clearAndRepaintLinePlusNPrevious(t.maxLine)
-	}
-
-	_, err := t.c.Write(t.outBuf)
-	t.outBuf = t.outBuf[:0]
-	return err
-}
-
-type pasteIndicatorError struct{}
-
-func (pasteIndicatorError) Error() string {
-	return "terminal: ErrPasteIndicator not correctly handled"
+	return term.NewTerminal(c, prompt)
 }
 
 // ErrPasteIndicator may be returned from ReadLine as the error, in addition
 // to valid line data. It indicates that bracketed paste mode is enabled and
 // that the returned line consists only of pasted data. Programs may wish to
 // interpret pasted data more literally than typed data.
-var ErrPasteIndicator = pasteIndicatorError{}
+var ErrPasteIndicator = term.ErrPasteIndicator
 
-// SetBracketedPasteMode requests that the terminal bracket paste operations
-// with markers. Not all terminals support this but, if it is supported, then
-// enabling this mode will stop any autocomplete callback from running due to
-// pastes. Additionally, any lines that are completely pasted will be returned
-// from ReadLine with the error set to ErrPasteIndicator.
-func (t *Terminal) SetBracketedPasteMode(on bool) {
-	if on {
-		io.WriteString(t.c, "\x1b[?2004h")
-	} else {
-		io.WriteString(t.c, "\x1b[?2004l")
-	}
-}
+// State contains the state of a terminal.
+type State = term.State
 
-// stRingBuffer is a ring buffer of strings.
-type stRingBuffer struct {
-	// entries contains max elements.
-	entries []string
-	max     int
-	// head contains the index of the element most recently added to the ring.
-	head int
-	// size contains the number of elements in the ring.
-	size int
+// IsTerminal returns whether the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	return term.IsTerminal(fd)
 }
 
-func (s *stRingBuffer) Add(a string) {
-	if s.entries == nil {
-		const defaultNumEntries = 100
-		s.entries = make([]string, defaultNumEntries)
-		s.max = defaultNumEntries
-	}
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	return term.ReadPassword(fd)
+}
 
-	s.head = (s.head + 1) % s.max
-	s.entries[s.head] = a
-	if s.size < s.max {
-		s.size++
-	}
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	return term.MakeRaw(fd)
 }
 
-// NthPreviousEntry returns the value passed to the nth previous call to Add.
-// If n is zero then the immediately prior value is returned, if one, then the
-// next most recent, and so on. If such an element doesn't exist then ok is
-// false.
-func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
-	if n >= s.size {
-		return "", false
-	}
-	index := s.head - n
-	if index < 0 {
-		index += s.max
-	}
-	return s.entries[index], true
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return term.Restore(fd, oldState)
 }
 
-// readPasswordLine reads from reader until it finds \n or io.EOF.
-// The slice returned does not include the \n.
-// readPasswordLine also ignores any \r it finds.
-// Windows uses \r as end of line. So, on Windows, readPasswordLine
-// reads until it finds \r and ignores any \n it finds during processing.
-func readPasswordLine(reader io.Reader) ([]byte, error) {
-	var buf [1]byte
-	var ret []byte
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	return term.GetState(fd)
+}
 
-	for {
-		n, err := reader.Read(buf[:])
-		if n > 0 {
-			switch buf[0] {
-			case '\b':
-				if len(ret) > 0 {
-					ret = ret[:len(ret)-1]
-				}
-			case '\n':
-				if runtime.GOOS != "windows" {
-					return ret, nil
-				}
-				// otherwise ignore \n
-			case '\r':
-				if runtime.GOOS == "windows" {
-					return ret, nil
-				}
-				// otherwise ignore \r
-			default:
-				ret = append(ret, buf[0])
-			}
-			continue
-		}
-		if err != nil {
-			if err == io.EOF && len(ret) > 0 {
-				return ret, nil
-			}
-			return ret, err
-		}
-	}
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	return term.GetSize(fd)
 }
diff --git a/vendor/golang.org/x/sys/plan9/asm.s b/vendor/golang.org/x/sys/plan9/asm.s
new file mode 100644
index 000000000..06449ebfa
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/asm.s
@@ -0,0 +1,8 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+TEXT ·use(SB),NOSPLIT,$0
+	RET
diff --git a/vendor/golang.org/x/sys/plan9/asm_plan9_386.s b/vendor/golang.org/x/sys/plan9/asm_plan9_386.s
new file mode 100644
index 000000000..bc5cab1f3
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/asm_plan9_386.s
@@ -0,0 +1,30 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+//
+// System call support for 386, Plan 9
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-32
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-44
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-36
+	JMP	syscall·seek(SB)
+
+TEXT ·exit(SB),NOSPLIT,$4-4
+	JMP	syscall·exit(SB)
diff --git a/vendor/golang.org/x/sys/plan9/asm_plan9_amd64.s b/vendor/golang.org/x/sys/plan9/asm_plan9_amd64.s
new file mode 100644
index 000000000..d3448e675
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/asm_plan9_amd64.s
@@ -0,0 +1,30 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+//
+// System call support for amd64, Plan 9
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-64
+	JMP	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-88
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-56
+	JMP	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-56
+	JMP	syscall·seek(SB)
+
+TEXT ·exit(SB),NOSPLIT,$8-8
+	JMP	syscall·exit(SB)
diff --git a/vendor/golang.org/x/sys/plan9/asm_plan9_arm.s b/vendor/golang.org/x/sys/plan9/asm_plan9_arm.s
new file mode 100644
index 000000000..afb7c0a9b
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/asm_plan9_arm.s
@@ -0,0 +1,25 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "textflag.h"
+
+// System call support for plan9 on arm
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT ·Syscall(SB),NOSPLIT,$0-32
+	JMP	syscall·Syscall(SB)
+
+TEXT ·Syscall6(SB),NOSPLIT,$0-44
+	JMP	syscall·Syscall6(SB)
+
+TEXT ·RawSyscall(SB),NOSPLIT,$0-28
+	JMP	syscall·RawSyscall(SB)
+
+TEXT ·RawSyscall6(SB),NOSPLIT,$0-40
+	JMP	syscall·RawSyscall6(SB)
+
+TEXT ·seek(SB),NOSPLIT,$0-36
+	JMP	syscall·exit(SB)
diff --git a/vendor/golang.org/x/sys/plan9/const_plan9.go b/vendor/golang.org/x/sys/plan9/const_plan9.go
new file mode 100644
index 000000000..b4e85a3a9
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/const_plan9.go
@@ -0,0 +1,70 @@
+package plan9
+
+// Plan 9 Constants
+
+// Open modes
+const (
+	O_RDONLY  = 0
+	O_WRONLY  = 1
+	O_RDWR    = 2
+	O_TRUNC   = 16
+	O_CLOEXEC = 32
+	O_EXCL    = 0x1000
+)
+
+// Rfork flags
+const (
+	RFNAMEG  = 1 << 0
+	RFENVG   = 1 << 1
+	RFFDG    = 1 << 2
+	RFNOTEG  = 1 << 3
+	RFPROC   = 1 << 4
+	RFMEM    = 1 << 5
+	RFNOWAIT = 1 << 6
+	RFCNAMEG = 1 << 10
+	RFCENVG  = 1 << 11
+	RFCFDG   = 1 << 12
+	RFREND   = 1 << 13
+	RFNOMNT  = 1 << 14
+)
+
+// Qid.Type bits
+const (
+	QTDIR    = 0x80
+	QTAPPEND = 0x40
+	QTEXCL   = 0x20
+	QTMOUNT  = 0x10
+	QTAUTH   = 0x08
+	QTTMP    = 0x04
+	QTFILE   = 0x00
+)
+
+// Dir.Mode bits
+const (
+	DMDIR    = 0x80000000
+	DMAPPEND = 0x40000000
+	DMEXCL   = 0x20000000
+	DMMOUNT  = 0x10000000
+	DMAUTH   = 0x08000000
+	DMTMP    = 0x04000000
+	DMREAD   = 0x4
+	DMWRITE  = 0x2
+	DMEXEC   = 0x1
+)
+
+const (
+	STATMAX    = 65535
+	ERRMAX     = 128
+	STATFIXLEN = 49
+)
+
+// Mount and bind flags
+const (
+	MREPL   = 0x0000
+	MBEFORE = 0x0001
+	MAFTER  = 0x0002
+	MORDER  = 0x0003
+	MCREATE = 0x0004
+	MCACHE  = 0x0010
+	MMASK   = 0x0017
+)
diff --git a/vendor/golang.org/x/sys/plan9/dir_plan9.go b/vendor/golang.org/x/sys/plan9/dir_plan9.go
new file mode 100644
index 000000000..0955e0c53
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/dir_plan9.go
@@ -0,0 +1,212 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 directory marshalling. See intro(5).
+
+package plan9
+
+import "errors"
+
+var (
+	ErrShortStat = errors.New("stat buffer too short")
+	ErrBadStat   = errors.New("malformed stat buffer")
+	ErrBadName   = errors.New("bad character in file name")
+)
+
+// A Qid represents a 9P server's unique identification for a file.
+type Qid struct {
+	Path uint64 // the file server's unique identification for the file
+	Vers uint32 // version number for given Path
+	Type uint8  // the type of the file (plan9.QTDIR for example)
+}
+
+// A Dir contains the metadata for a file.
+type Dir struct {
+	// system-modified data
+	Type uint16 // server type
+	Dev  uint32 // server subtype
+
+	// file data
+	Qid    Qid    // unique id from server
+	Mode   uint32 // permissions
+	Atime  uint32 // last read time
+	Mtime  uint32 // last write time
+	Length int64  // file length
+	Name   string // last element of path
+	Uid    string // owner name
+	Gid    string // group name
+	Muid   string // last modifier name
+}
+
+var nullDir = Dir{
+	Type: ^uint16(0),
+	Dev:  ^uint32(0),
+	Qid: Qid{
+		Path: ^uint64(0),
+		Vers: ^uint32(0),
+		Type: ^uint8(0),
+	},
+	Mode:   ^uint32(0),
+	Atime:  ^uint32(0),
+	Mtime:  ^uint32(0),
+	Length: ^int64(0),
+}
+
+// Null assigns special "don't touch" values to members of d to
+// avoid modifying them during plan9.Wstat.
+func (d *Dir) Null() { *d = nullDir }
+
+// Marshal encodes a 9P stat message corresponding to d into b
+//
+// If there isn't enough space in b for a stat message, ErrShortStat is returned.
+func (d *Dir) Marshal(b []byte) (n int, err error) {
+	n = STATFIXLEN + len(d.Name) + len(d.Uid) + len(d.Gid) + len(d.Muid)
+	if n > len(b) {
+		return n, ErrShortStat
+	}
+
+	for _, c := range d.Name {
+		if c == '/' {
+			return n, ErrBadName
+		}
+	}
+
+	b = pbit16(b, uint16(n)-2)
+	b = pbit16(b, d.Type)
+	b = pbit32(b, d.Dev)
+	b = pbit8(b, d.Qid.Type)
+	b = pbit32(b, d.Qid.Vers)
+	b = pbit64(b, d.Qid.Path)
+	b = pbit32(b, d.Mode)
+	b = pbit32(b, d.Atime)
+	b = pbit32(b, d.Mtime)
+	b = pbit64(b, uint64(d.Length))
+	b = pstring(b, d.Name)
+	b = pstring(b, d.Uid)
+	b = pstring(b, d.Gid)
+	b = pstring(b, d.Muid)
+
+	return n, nil
+}
+
+// UnmarshalDir decodes a single 9P stat message from b and returns the resulting Dir.
+//
+// If b is too small to hold a valid stat message, ErrShortStat is returned.
+//
+// If the stat message itself is invalid, ErrBadStat is returned.
+func UnmarshalDir(b []byte) (*Dir, error) {
+	if len(b) < STATFIXLEN {
+		return nil, ErrShortStat
+	}
+	size, buf := gbit16(b)
+	if len(b) != int(size)+2 {
+		return nil, ErrBadStat
+	}
+	b = buf
+
+	var d Dir
+	d.Type, b = gbit16(b)
+	d.Dev, b = gbit32(b)
+	d.Qid.Type, b = gbit8(b)
+	d.Qid.Vers, b = gbit32(b)
+	d.Qid.Path, b = gbit64(b)
+	d.Mode, b = gbit32(b)
+	d.Atime, b = gbit32(b)
+	d.Mtime, b = gbit32(b)
+
+	n, b := gbit64(b)
+	d.Length = int64(n)
+
+	var ok bool
+	if d.Name, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Uid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Gid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+	if d.Muid, b, ok = gstring(b); !ok {
+		return nil, ErrBadStat
+	}
+
+	return &d, nil
+}
+
+// pbit8 copies the 8-bit number v to b and returns the remaining slice of b.
+func pbit8(b []byte, v uint8) []byte {
+	b[0] = byte(v)
+	return b[1:]
+}
+
+// pbit16 copies the 16-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit16(b []byte, v uint16) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	return b[2:]
+}
+
+// pbit32 copies the 32-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit32(b []byte, v uint32) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+	return b[4:]
+}
+
+// pbit64 copies the 64-bit number v to b in little-endian order and returns the remaining slice of b.
+func pbit64(b []byte, v uint64) []byte {
+	b[0] = byte(v)
+	b[1] = byte(v >> 8)
+	b[2] = byte(v >> 16)
+	b[3] = byte(v >> 24)
+	b[4] = byte(v >> 32)
+	b[5] = byte(v >> 40)
+	b[6] = byte(v >> 48)
+	b[7] = byte(v >> 56)
+	return b[8:]
+}
+
+// pstring copies the string s to b, prepending it with a 16-bit length in little-endian order, and
+// returning the remaining slice of b..
+func pstring(b []byte, s string) []byte {
+	b = pbit16(b, uint16(len(s)))
+	n := copy(b, s)
+	return b[n:]
+}
+
+// gbit8 reads an 8-bit number from b and returns it with the remaining slice of b.
+func gbit8(b []byte) (uint8, []byte) {
+	return uint8(b[0]), b[1:]
+}
+
+// gbit16 reads a 16-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit16(b []byte) (uint16, []byte) {
+	return uint16(b[0]) | uint16(b[1])<<8, b[2:]
+}
+
+// gbit32 reads a 32-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit32(b []byte) (uint32, []byte) {
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24, b[4:]
+}
+
+// gbit64 reads a 64-bit number in little-endian order from b and returns it with the remaining slice of b.
+func gbit64(b []byte) (uint64, []byte) {
+	lo := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+	hi := uint32(b[4]) | uint32(b[5])<<8 | uint32(b[6])<<16 | uint32(b[7])<<24
+	return uint64(lo) | uint64(hi)<<32, b[8:]
+}
+
+// gstring reads a string from b, prefixed with a 16-bit length in little-endian order.
+// It returns the string with the remaining slice of b and a boolean. If the length is
+// greater than the number of bytes in b, the boolean will be false.
+func gstring(b []byte) (string, []byte, bool) {
+	n, b := gbit16(b)
+	if int(n) > len(b) {
+		return "", b, false
+	}
+	return string(b[:n]), b[n:], true
+}
diff --git a/vendor/golang.org/x/sys/plan9/env_plan9.go b/vendor/golang.org/x/sys/plan9/env_plan9.go
new file mode 100644
index 000000000..8f1918004
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/env_plan9.go
@@ -0,0 +1,31 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 environment variables.
+
+package plan9
+
+import (
+	"syscall"
+)
+
+func Getenv(key string) (value string, found bool) {
+	return syscall.Getenv(key)
+}
+
+func Setenv(key, value string) error {
+	return syscall.Setenv(key, value)
+}
+
+func Clearenv() {
+	syscall.Clearenv()
+}
+
+func Environ() []string {
+	return syscall.Environ()
+}
+
+func Unsetenv(key string) error {
+	return syscall.Unsetenv(key)
+}
diff --git a/vendor/golang.org/x/sys/plan9/errors_plan9.go b/vendor/golang.org/x/sys/plan9/errors_plan9.go
new file mode 100644
index 000000000..65fe74d3e
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/errors_plan9.go
@@ -0,0 +1,50 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package plan9
+
+import "syscall"
+
+// Constants
+const (
+	// Invented values to support what package os expects.
+	O_CREAT    = 0x02000
+	O_APPEND   = 0x00400
+	O_NOCTTY   = 0x00000
+	O_NONBLOCK = 0x00000
+	O_SYNC     = 0x00000
+	O_ASYNC    = 0x00000
+
+	S_IFMT   = 0x1f000
+	S_IFIFO  = 0x1000
+	S_IFCHR  = 0x2000
+	S_IFDIR  = 0x4000
+	S_IFBLK  = 0x6000
+	S_IFREG  = 0x8000
+	S_IFLNK  = 0xa000
+	S_IFSOCK = 0xc000
+)
+
+// Errors
+var (
+	EINVAL       = syscall.NewError("bad arg in system call")
+	ENOTDIR      = syscall.NewError("not a directory")
+	EISDIR       = syscall.NewError("file is a directory")
+	ENOENT       = syscall.NewError("file does not exist")
+	EEXIST       = syscall.NewError("file already exists")
+	EMFILE       = syscall.NewError("no free file descriptors")
+	EIO          = syscall.NewError("i/o error")
+	ENAMETOOLONG = syscall.NewError("file name too long")
+	EINTR        = syscall.NewError("interrupted")
+	EPERM        = syscall.NewError("permission denied")
+	EBUSY        = syscall.NewError("no free devices")
+	ETIMEDOUT    = syscall.NewError("connection timed out")
+	EPLAN9       = syscall.NewError("not supported by plan 9")
+
+	// The following errors do not correspond to any
+	// Plan 9 system messages. Invented to support
+	// what package os and others expect.
+	EACCES       = syscall.NewError("access permission denied")
+	EAFNOSUPPORT = syscall.NewError("address family not supported by protocol")
+)
diff --git a/vendor/golang.org/x/sys/plan9/mkall.sh b/vendor/golang.org/x/sys/plan9/mkall.sh
new file mode 100644
index 000000000..1650fbcc7
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/mkall.sh
@@ -0,0 +1,150 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# The plan9 package provides access to the raw system call
+# interface of the underlying operating system.  Porting Go to
+# a new architecture/operating system combination requires
+# some manual effort, though there are tools that automate
+# much of the process.  The auto-generated files have names
+# beginning with z.
+#
+# This script runs or (given -n) prints suggested commands to generate z files
+# for the current system.  Running those commands is not automatic.
+# This script is documentation more than anything else.
+#
+# * asm_${GOOS}_${GOARCH}.s
+#
+# This hand-written assembly file implements system call dispatch.
+# There are three entry points:
+#
+# 	func Syscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr);
+# 	func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr);
+# 	func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr);
+#
+# The first and second are the standard ones; they differ only in
+# how many arguments can be passed to the kernel.
+# The third is for low-level use by the ForkExec wrapper;
+# unlike the first two, it does not call into the scheduler to
+# let it know that a system call is running.
+#
+# * syscall_${GOOS}.go
+#
+# This hand-written Go file implements system calls that need
+# special handling and lists "//sys" comments giving prototypes
+# for ones that can be auto-generated.  Mksyscall reads those
+# comments to generate the stubs.
+#
+# * syscall_${GOOS}_${GOARCH}.go
+#
+# Same as syscall_${GOOS}.go except that it contains code specific
+# to ${GOOS} on one particular architecture.
+#
+# * types_${GOOS}.c
+#
+# This hand-written C file includes standard C headers and then
+# creates typedef or enum names beginning with a dollar sign
+# (use of $ in variable names is a gcc extension).  The hardest
+# part about preparing this file is figuring out which headers to
+# include and which symbols need to be #defined to get the
+# actual data structures that pass through to the kernel system calls.
+# Some C libraries present alternate versions for binary compatibility
+# and translate them on the way in and out of system calls, but
+# there is almost always a #define that can get the real ones.
+# See types_darwin.c and types_linux.c for examples.
+#
+# * zerror_${GOOS}_${GOARCH}.go
+#
+# This machine-generated file defines the system's error numbers,
+# error strings, and signal numbers.  The generator is "mkerrors.sh".
+# Usually no arguments are needed, but mkerrors.sh will pass its
+# arguments on to godefs.
+#
+# * zsyscall_${GOOS}_${GOARCH}.go
+#
+# Generated by mksyscall.pl; see syscall_${GOOS}.go above.
+#
+# * zsysnum_${GOOS}_${GOARCH}.go
+#
+# Generated by mksysnum_${GOOS}.
+#
+# * ztypes_${GOOS}_${GOARCH}.go
+#
+# Generated by godefs; see types_${GOOS}.c above.
+
+GOOSARCH="${GOOS}_${GOARCH}"
+
+# defaults
+mksyscall="go run mksyscall.go"
+mkerrors="./mkerrors.sh"
+zerrors="zerrors_$GOOSARCH.go"
+mksysctl=""
+zsysctl="zsysctl_$GOOSARCH.go"
+mksysnum=
+mktypes=
+run="sh"
+
+case "$1" in
+-syscalls)
+	for i in zsyscall*go
+	do
+		sed 1q $i | sed 's;^// ;;' | sh > _$i && gofmt < _$i > $i
+		rm _$i
+	done
+	exit 0
+	;;
+-n)
+	run="cat"
+	shift
+esac
+
+case "$#" in
+0)
+	;;
+*)
+	echo 'usage: mkall.sh [-n]' 1>&2
+	exit 2
+esac
+
+case "$GOOSARCH" in
+_* | *_ | _)
+	echo 'undefined $GOOS_$GOARCH:' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+plan9_386)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,386"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+plan9_amd64)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,amd64"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+plan9_arm)
+	mkerrors=
+	mksyscall="go run mksyscall.go -l32 -plan9 -tags plan9,arm"
+	mksysnum="./mksysnum_plan9.sh /n/sources/plan9/sys/src/libc/9syscall/sys.h"
+	mktypes="XXX"
+	;;
+*)
+	echo 'unrecognized $GOOS_$GOARCH: ' "$GOOSARCH" 1>&2
+	exit 1
+	;;
+esac
+
+(
+	if [ -n "$mkerrors" ]; then echo "$mkerrors |gofmt >$zerrors"; fi
+	case "$GOOS" in
+	plan9)
+		syscall_goos="syscall_$GOOS.go"
+		if [ -n "$mksyscall" ]; then echo "$mksyscall $syscall_goos |gofmt >zsyscall_$GOOSARCH.go"; fi
+		;;
+	esac
+	if [ -n "$mksysctl" ]; then echo "$mksysctl |gofmt >$zsysctl"; fi
+	if [ -n "$mksysnum" ]; then echo "$mksysnum |gofmt >zsysnum_$GOOSARCH.go"; fi
+	if [ -n "$mktypes" ]; then echo "$mktypes types_$GOOS.go |gofmt >ztypes_$GOOSARCH.go"; fi
+) | $run
diff --git a/vendor/golang.org/x/sys/plan9/mkerrors.sh b/vendor/golang.org/x/sys/plan9/mkerrors.sh
new file mode 100644
index 000000000..85309c4a5
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/mkerrors.sh
@@ -0,0 +1,246 @@
+#!/usr/bin/env bash
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# Generate Go code listing errors and other #defined constant
+# values (ENAMETOOLONG etc.), by asking the preprocessor
+# about the definitions.
+
+unset LANG
+export LC_ALL=C
+export LC_CTYPE=C
+
+CC=${CC:-gcc}
+
+uname=$(uname)
+
+includes='
+#include <sys/types.h>
+#include <sys/file.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <errno.h>
+#include <sys/signal.h>
+#include <signal.h>
+#include <sys/resource.h>
+'
+
+ccflags="$@"
+
+# Write go tool cgo -godefs input.
+(
+	echo package plan9
+	echo
+	echo '/*'
+	indirect="includes_$(uname)"
+	echo "${!indirect} $includes"
+	echo '*/'
+	echo 'import "C"'
+	echo
+	echo 'const ('
+
+	# The gcc command line prints all the #defines
+	# it encounters while processing the input
+	echo "${!indirect} $includes" | $CC -x c - -E -dM $ccflags |
+	awk '
+		$1 != "#define" || $2 ~ /\(/ || $3 == "" {next}
+
+		$2 ~ /^E([ABCD]X|[BIS]P|[SD]I|S|FL)$/ {next}  # 386 registers
+		$2 ~ /^(SIGEV_|SIGSTKSZ|SIGRT(MIN|MAX))/ {next}
+		$2 ~ /^(SCM_SRCRT)$/ {next}
+		$2 ~ /^(MAP_FAILED)$/ {next}
+
+		$2 !~ /^ETH_/ &&
+		$2 !~ /^EPROC_/ &&
+		$2 !~ /^EQUIV_/ &&
+		$2 !~ /^EXPR_/ &&
+		$2 ~ /^E[A-Z0-9_]+$/ ||
+		$2 ~ /^B[0-9_]+$/ ||
+		$2 ~ /^V[A-Z0-9]+$/ ||
+		$2 ~ /^CS[A-Z0-9]/ ||
+		$2 ~ /^I(SIG|CANON|CRNL|EXTEN|MAXBEL|STRIP|UTF8)$/ ||
+		$2 ~ /^IGN/ ||
+		$2 ~ /^IX(ON|ANY|OFF)$/ ||
+		$2 ~ /^IN(LCR|PCK)$/ ||
+		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
+		$2 ~ /^C(LOCAL|READ)$/ ||
+		$2 == "BRKINT" ||
+		$2 == "HUPCL" ||
+		$2 == "PENDIN" ||
+		$2 == "TOSTOP" ||
+		$2 ~ /^PAR/ ||
+		$2 ~ /^SIG[^_]/ ||
+		$2 ~ /^O[CNPFP][A-Z]+[^_][A-Z]+$/ ||
+		$2 ~ /^IN_/ ||
+		$2 ~ /^LOCK_(SH|EX|NB|UN)$/ ||
+		$2 ~ /^(AF|SOCK|SO|SOL|IPPROTO|IP|IPV6|ICMP6|TCP|EVFILT|NOTE|EV|SHUT|PROT|MAP|PACKET|MSG|SCM|MCL|DT|MADV|PR)_/ ||
+		$2 == "ICMPV6_FILTER" ||
+		$2 == "SOMAXCONN" ||
+		$2 == "NAME_MAX" ||
+		$2 == "IFNAMSIZ" ||
+		$2 ~ /^CTL_(MAXNAME|NET|QUERY)$/ ||
+		$2 ~ /^SYSCTL_VERS/ ||
+		$2 ~ /^(MS|MNT)_/ ||
+		$2 ~ /^TUN(SET|GET|ATTACH|DETACH)/ ||
+		$2 ~ /^(O|F|FD|NAME|S|PTRACE|PT)_/ ||
+		$2 ~ /^LINUX_REBOOT_CMD_/ ||
+		$2 ~ /^LINUX_REBOOT_MAGIC[12]$/ ||
+		$2 !~ "NLA_TYPE_MASK" &&
+		$2 ~ /^(NETLINK|NLM|NLMSG|NLA|IFA|IFAN|RT|RTCF|RTN|RTPROT|RTNH|ARPHRD|ETH_P)_/ ||
+		$2 ~ /^SIOC/ ||
+		$2 ~ /^TIOC/ ||
+		$2 !~ "RTF_BITS" &&
+		$2 ~ /^(IFF|IFT|NET_RT|RTM|RTF|RTV|RTA|RTAX)_/ ||
+		$2 ~ /^BIOC/ ||
+		$2 ~ /^RUSAGE_(SELF|CHILDREN|THREAD)/ ||
+		$2 ~ /^RLIMIT_(AS|CORE|CPU|DATA|FSIZE|NOFILE|STACK)|RLIM_INFINITY/ ||
+		$2 ~ /^PRIO_(PROCESS|PGRP|USER)/ ||
+		$2 ~ /^CLONE_[A-Z_]+/ ||
+		$2 !~ /^(BPF_TIMEVAL)$/ &&
+		$2 ~ /^(BPF|DLT)_/ ||
+		$2 !~ "WMESGLEN" &&
+		$2 ~ /^W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", $2, $2)}
+		$2 ~ /^__WCOREFLAG$/ {next}
+		$2 ~ /^__W[A-Z0-9]+$/ {printf("\t%s = C.%s\n", substr($2,3), $2)}
+
+		{next}
+	' | sort
+
+	echo ')'
+) >_const.go
+
+# Pull out the error names for later.
+errors=$(
+	echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print $2 }' |
+	sort
+)
+
+# Pull out the signal names for later.
+signals=$(
+	echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print $2 }' |
+	egrep -v '(SIGSTKSIZE|SIGSTKSZ|SIGRT)' |
+	sort
+)
+
+# Again, writing regexps to a file.
+echo '#include <errno.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^E[A-Z0-9_]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	sort >_error.grep
+echo '#include <signal.h>' | $CC -x c - -E -dM $ccflags |
+	awk '$1=="#define" && $2 ~ /^SIG[A-Z0-9]+$/ { print "^\t" $2 "[ \t]*=" }' |
+	egrep -v '(SIGSTKSIZE|SIGSTKSZ|SIGRT)' |
+	sort >_signal.grep
+
+echo '// mkerrors.sh' "$@"
+echo '// Code generated by the command above; DO NOT EDIT.'
+echo
+go tool cgo -godefs -- "$@" _const.go >_error.out
+cat _error.out | grep -vf _error.grep | grep -vf _signal.grep
+echo
+echo '// Errors'
+echo 'const ('
+cat _error.out | grep -f _error.grep | sed 's/=\(.*\)/= Errno(\1)/'
+echo ')'
+
+echo
+echo '// Signals'
+echo 'const ('
+cat _error.out | grep -f _signal.grep | sed 's/=\(.*\)/= Signal(\1)/'
+echo ')'
+
+# Run C program to print error and syscall strings.
+(
+	echo -E "
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+#include <signal.h>
+
+#define nelem(x) (sizeof(x)/sizeof((x)[0]))
+
+enum { A = 'A', Z = 'Z', a = 'a', z = 'z' }; // avoid need for single quotes below
+
+int errors[] = {
+"
+	for i in $errors
+	do
+		echo -E '	'$i,
+	done
+
+	echo -E "
+};
+
+int signals[] = {
+"
+	for i in $signals
+	do
+		echo -E '	'$i,
+	done
+
+	# Use -E because on some systems bash builtin interprets \n itself.
+	echo -E '
+};
+
+static int
+intcmp(const void *a, const void *b)
+{
+	return *(int*)a - *(int*)b;
+}
+
+int
+main(void)
+{
+	int i, j, e;
+	char buf[1024], *p;
+
+	printf("\n\n// Error table\n");
+	printf("var errors = [...]string {\n");
+	qsort(errors, nelem(errors), sizeof errors[0], intcmp);
+	for(i=0; i<nelem(errors); i++) {
+		e = errors[i];
+		if(i > 0 && errors[i-1] == e)
+			continue;
+		strcpy(buf, strerror(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+	
+	printf("\n\n// Signal table\n");
+	printf("var signals = [...]string {\n");
+	qsort(signals, nelem(signals), sizeof signals[0], intcmp);
+	for(i=0; i<nelem(signals); i++) {
+		e = signals[i];
+		if(i > 0 && signals[i-1] == e)
+			continue;
+		strcpy(buf, strsignal(e));
+		// lowercase first letter: Bad -> bad, but STREAM -> STREAM.
+		if(A <= buf[0] && buf[0] <= Z && a <= buf[1] && buf[1] <= z)
+			buf[0] += a - A;
+		// cut trailing : number.
+		p = strrchr(buf, ":"[0]);
+		if(p)
+			*p = '\0';
+		printf("\t%d: \"%s\",\n", e, buf);
+	}
+	printf("}\n\n");
+
+	return 0;
+}
+
+'
+) >_errors.c
+
+$CC $ccflags -o _errors _errors.c && $GORUN ./_errors && rm -f _errors.c _errors _const.go _error.grep _signal.grep _error.out
diff --git a/vendor/golang.org/x/sys/plan9/mksysnum_plan9.sh b/vendor/golang.org/x/sys/plan9/mksysnum_plan9.sh
new file mode 100644
index 000000000..3c3ab0581
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/mksysnum_plan9.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+COMMAND="mksysnum_plan9.sh $@"
+
+cat <<EOF
+// $COMMAND
+// MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
+
+package plan9
+
+const(
+EOF
+
+SP='[ 	]' # space or tab
+sed "s/^#define${SP}\\([A-Z0-9_][A-Z0-9_]*\\)${SP}${SP}*\\([0-9][0-9]*\\)/SYS_\\1=\\2/g" \
+	< $1 | grep -v SYS__
+
+cat <<EOF
+)
+EOF
diff --git a/vendor/golang.org/x/sys/plan9/pwd_go15_plan9.go b/vendor/golang.org/x/sys/plan9/pwd_go15_plan9.go
new file mode 100644
index 000000000..87ae9d2a3
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/pwd_go15_plan9.go
@@ -0,0 +1,21 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.5
+
+package plan9
+
+import "syscall"
+
+func fixwd() {
+	syscall.Fixwd()
+}
+
+func Getwd() (wd string, err error) {
+	return syscall.Getwd()
+}
+
+func Chdir(path string) error {
+	return syscall.Chdir(path)
+}
diff --git a/vendor/golang.org/x/sys/plan9/pwd_plan9.go b/vendor/golang.org/x/sys/plan9/pwd_plan9.go
new file mode 100644
index 000000000..c07c798bc
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/pwd_plan9.go
@@ -0,0 +1,23 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.5
+
+package plan9
+
+func fixwd() {
+}
+
+func Getwd() (wd string, err error) {
+	fd, err := open(".", O_RDONLY)
+	if err != nil {
+		return "", err
+	}
+	defer Close(fd)
+	return Fd2path(fd)
+}
+
+func Chdir(path string) error {
+	return chdir(path)
+}
diff --git a/vendor/golang.org/x/sys/plan9/race.go b/vendor/golang.org/x/sys/plan9/race.go
new file mode 100644
index 000000000..42edd93ef
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/race.go
@@ -0,0 +1,30 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9,race
+
+package plan9
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+const raceenabled = true
+
+func raceAcquire(addr unsafe.Pointer) {
+	runtime.RaceAcquire(addr)
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+	runtime.RaceReleaseMerge(addr)
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+	runtime.RaceReadRange(addr, len)
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+	runtime.RaceWriteRange(addr, len)
+}
diff --git a/vendor/golang.org/x/sys/plan9/race0.go b/vendor/golang.org/x/sys/plan9/race0.go
new file mode 100644
index 000000000..c89cf8fc0
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/race0.go
@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9,!race
+
+package plan9
+
+import (
+	"unsafe"
+)
+
+const raceenabled = false
+
+func raceAcquire(addr unsafe.Pointer) {
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+}
diff --git a/vendor/golang.org/x/sys/plan9/str.go b/vendor/golang.org/x/sys/plan9/str.go
new file mode 100644
index 000000000..4f7f9ad7c
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/str.go
@@ -0,0 +1,22 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9
+
+package plan9
+
+func itoa(val int) string { // do it here rather than with fmt to avoid dependency
+	if val < 0 {
+		return "-" + itoa(-val)
+	}
+	var buf [32]byte // big enough for int64
+	i := len(buf) - 1
+	for val >= 10 {
+		buf[i] = byte(val%10 + '0')
+		i--
+		val /= 10
+	}
+	buf[i] = byte(val + '0')
+	return string(buf[i:])
+}
diff --git a/vendor/golang.org/x/sys/plan9/syscall.go b/vendor/golang.org/x/sys/plan9/syscall.go
new file mode 100644
index 000000000..e7363a2f5
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/syscall.go
@@ -0,0 +1,116 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build plan9
+
+// Package plan9 contains an interface to the low-level operating system
+// primitives. OS details vary depending on the underlying system, and
+// by default, godoc will display the OS-specific documentation for the current
+// system. If you want godoc to display documentation for another
+// system, set $GOOS and $GOARCH to the desired system. For example, if
+// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
+// to freebsd and $GOARCH to arm.
+//
+// The primary use of this package is inside other packages that provide a more
+// portable interface to the system, such as "os", "time" and "net".  Use
+// those packages rather than this one if you can.
+//
+// For details of the functions and data types in this package consult
+// the manuals for the appropriate operating system.
+//
+// These calls return err == nil to indicate success; otherwise
+// err represents an operating system error describing the failure and
+// holds a value of type syscall.ErrorString.
+package plan9 // import "golang.org/x/sys/plan9"
+
+import (
+	"bytes"
+	"strings"
+	"unsafe"
+
+	"golang.org/x/sys/internal/unsafeheader"
+)
+
+// ByteSliceFromString returns a NUL-terminated slice of bytes
+// containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func ByteSliceFromString(s string) ([]byte, error) {
+	if strings.IndexByte(s, 0) != -1 {
+		return nil, EINVAL
+	}
+	a := make([]byte, len(s)+1)
+	copy(a, s)
+	return a, nil
+}
+
+// BytePtrFromString returns a pointer to a NUL-terminated array of
+// bytes containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func BytePtrFromString(s string) (*byte, error) {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		return nil, err
+	}
+	return &a[0], nil
+}
+
+// ByteSliceToString returns a string form of the text represented by the slice s, with a terminating NUL and any
+// bytes after the NUL removed.
+func ByteSliceToString(s []byte) string {
+	if i := bytes.IndexByte(s, 0); i != -1 {
+		s = s[:i]
+	}
+	return string(s)
+}
+
+// BytePtrToString takes a pointer to a sequence of text and returns the corresponding string.
+// If the pointer is nil, it returns the empty string. It assumes that the text sequence is terminated
+// at a zero byte; if the zero byte is not present, the program may crash.
+func BytePtrToString(p *byte) string {
+	if p == nil {
+		return ""
+	}
+	if *p == 0 {
+		return ""
+	}
+
+	// Find NUL terminator.
+	n := 0
+	for ptr := unsafe.Pointer(p); *(*byte)(ptr) != 0; n++ {
+		ptr = unsafe.Pointer(uintptr(ptr) + 1)
+	}
+
+	var s []byte
+	h := (*unsafeheader.Slice)(unsafe.Pointer(&s))
+	h.Data = unsafe.Pointer(p)
+	h.Len = n
+	h.Cap = n
+
+	return string(s)
+}
+
+// Single-word zero for use when we need a valid pointer to 0 bytes.
+// See mksyscall.pl.
+var _zero uintptr
+
+func (ts *Timespec) Unix() (sec int64, nsec int64) {
+	return int64(ts.Sec), int64(ts.Nsec)
+}
+
+func (tv *Timeval) Unix() (sec int64, nsec int64) {
+	return int64(tv.Sec), int64(tv.Usec) * 1000
+}
+
+func (ts *Timespec) Nano() int64 {
+	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
+}
+
+func (tv *Timeval) Nano() int64 {
+	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
+}
+
+// use is a no-op, but the compiler cannot see that it is.
+// Calling use(p) ensures that p is kept live until that point.
+//go:noescape
+func use(p unsafe.Pointer)
diff --git a/vendor/golang.org/x/sys/plan9/syscall_plan9.go b/vendor/golang.org/x/sys/plan9/syscall_plan9.go
new file mode 100644
index 000000000..84e147148
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/syscall_plan9.go
@@ -0,0 +1,349 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Plan 9 system calls.
+// This file is compiled as ordinary Go code,
+// but it is also input to mksyscall,
+// which parses the //sys lines and generates system call stubs.
+// Note that sometimes we use a lowercase //sys name and
+// wrap it in our own nicer implementation.
+
+package plan9
+
+import (
+	"bytes"
+	"syscall"
+	"unsafe"
+)
+
+// A Note is a string describing a process note.
+// It implements the os.Signal interface.
+type Note string
+
+func (n Note) Signal() {}
+
+func (n Note) String() string {
+	return string(n)
+}
+
+var (
+	Stdin  = 0
+	Stdout = 1
+	Stderr = 2
+)
+
+// For testing: clients can set this flag to force
+// creation of IPv6 sockets to return EAFNOSUPPORT.
+var SocketDisableIPv6 bool
+
+func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
+func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
+func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
+func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
+
+func atoi(b []byte) (n uint) {
+	n = 0
+	for i := 0; i < len(b); i++ {
+		n = n*10 + uint(b[i]-'0')
+	}
+	return
+}
+
+func cstring(s []byte) string {
+	i := bytes.IndexByte(s, 0)
+	if i == -1 {
+		i = len(s)
+	}
+	return string(s[:i])
+}
+
+func errstr() string {
+	var buf [ERRMAX]byte
+
+	RawSyscall(SYS_ERRSTR, uintptr(unsafe.Pointer(&buf[0])), uintptr(len(buf)), 0)
+
+	buf[len(buf)-1] = 0
+	return cstring(buf[:])
+}
+
+// Implemented in assembly to import from runtime.
+func exit(code int)
+
+func Exit(code int) { exit(code) }
+
+func readnum(path string) (uint, error) {
+	var b [12]byte
+
+	fd, e := Open(path, O_RDONLY)
+	if e != nil {
+		return 0, e
+	}
+	defer Close(fd)
+
+	n, e := Pread(fd, b[:], 0)
+
+	if e != nil {
+		return 0, e
+	}
+
+	m := 0
+	for ; m < n && b[m] == ' '; m++ {
+	}
+
+	return atoi(b[m : n-1]), nil
+}
+
+func Getpid() (pid int) {
+	n, _ := readnum("#c/pid")
+	return int(n)
+}
+
+func Getppid() (ppid int) {
+	n, _ := readnum("#c/ppid")
+	return int(n)
+}
+
+func Read(fd int, p []byte) (n int, err error) {
+	return Pread(fd, p, -1)
+}
+
+func Write(fd int, p []byte) (n int, err error) {
+	return Pwrite(fd, p, -1)
+}
+
+var ioSync int64
+
+//sys	fd2path(fd int, buf []byte) (err error)
+func Fd2path(fd int) (path string, err error) {
+	var buf [512]byte
+
+	e := fd2path(fd, buf[:])
+	if e != nil {
+		return "", e
+	}
+	return cstring(buf[:]), nil
+}
+
+//sys	pipe(p *[2]int32) (err error)
+func Pipe(p []int) (err error) {
+	if len(p) != 2 {
+		return syscall.ErrorString("bad arg in system call")
+	}
+	var pp [2]int32
+	err = pipe(&pp)
+	p[0] = int(pp[0])
+	p[1] = int(pp[1])
+	return
+}
+
+// Underlying system call writes to newoffset via pointer.
+// Implemented in assembly to avoid allocation.
+func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
+
+func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
+	newoffset, e := seek(0, fd, offset, whence)
+
+	if newoffset == -1 {
+		err = syscall.ErrorString(e)
+	}
+	return
+}
+
+func Mkdir(path string, mode uint32) (err error) {
+	fd, err := Create(path, O_RDONLY, DMDIR|mode)
+
+	if fd != -1 {
+		Close(fd)
+	}
+
+	return
+}
+
+type Waitmsg struct {
+	Pid  int
+	Time [3]uint32
+	Msg  string
+}
+
+func (w Waitmsg) Exited() bool   { return true }
+func (w Waitmsg) Signaled() bool { return false }
+
+func (w Waitmsg) ExitStatus() int {
+	if len(w.Msg) == 0 {
+		// a normal exit returns no message
+		return 0
+	}
+	return 1
+}
+
+//sys	await(s []byte) (n int, err error)
+func Await(w *Waitmsg) (err error) {
+	var buf [512]byte
+	var f [5][]byte
+
+	n, err := await(buf[:])
+
+	if err != nil || w == nil {
+		return
+	}
+
+	nf := 0
+	p := 0
+	for i := 0; i < n && nf < len(f)-1; i++ {
+		if buf[i] == ' ' {
+			f[nf] = buf[p:i]
+			p = i + 1
+			nf++
+		}
+	}
+	f[nf] = buf[p:]
+	nf++
+
+	if nf != len(f) {
+		return syscall.ErrorString("invalid wait message")
+	}
+	w.Pid = int(atoi(f[0]))
+	w.Time[0] = uint32(atoi(f[1]))
+	w.Time[1] = uint32(atoi(f[2]))
+	w.Time[2] = uint32(atoi(f[3]))
+	w.Msg = cstring(f[4])
+	if w.Msg == "''" {
+		// await() returns '' for no error
+		w.Msg = ""
+	}
+	return
+}
+
+func Unmount(name, old string) (err error) {
+	fixwd()
+	oldp, err := BytePtrFromString(old)
+	if err != nil {
+		return err
+	}
+	oldptr := uintptr(unsafe.Pointer(oldp))
+
+	var r0 uintptr
+	var e syscall.ErrorString
+
+	// bind(2) man page: If name is zero, everything bound or mounted upon old is unbound or unmounted.
+	if name == "" {
+		r0, _, e = Syscall(SYS_UNMOUNT, _zero, oldptr, 0)
+	} else {
+		namep, err := BytePtrFromString(name)
+		if err != nil {
+			return err
+		}
+		r0, _, e = Syscall(SYS_UNMOUNT, uintptr(unsafe.Pointer(namep)), oldptr, 0)
+	}
+
+	if int32(r0) == -1 {
+		err = e
+	}
+	return
+}
+
+func Fchdir(fd int) (err error) {
+	path, err := Fd2path(fd)
+
+	if err != nil {
+		return
+	}
+
+	return Chdir(path)
+}
+
+type Timespec struct {
+	Sec  int32
+	Nsec int32
+}
+
+type Timeval struct {
+	Sec  int32
+	Usec int32
+}
+
+func NsecToTimeval(nsec int64) (tv Timeval) {
+	nsec += 999 // round up to microsecond
+	tv.Usec = int32(nsec % 1e9 / 1e3)
+	tv.Sec = int32(nsec / 1e9)
+	return
+}
+
+func nsec() int64 {
+	var scratch int64
+
+	r0, _, _ := Syscall(SYS_NSEC, uintptr(unsafe.Pointer(&scratch)), 0, 0)
+	// TODO(aram): remove hack after I fix _nsec in the pc64 kernel.
+	if r0 == 0 {
+		return scratch
+	}
+	return int64(r0)
+}
+
+func Gettimeofday(tv *Timeval) error {
+	nsec := nsec()
+	*tv = NsecToTimeval(nsec)
+	return nil
+}
+
+func Getpagesize() int { return 0x1000 }
+
+func Getegid() (egid int) { return -1 }
+func Geteuid() (euid int) { return -1 }
+func Getgid() (gid int)   { return -1 }
+func Getuid() (uid int)   { return -1 }
+
+func Getgroups() (gids []int, err error) {
+	return make([]int, 0), nil
+}
+
+//sys	open(path string, mode int) (fd int, err error)
+func Open(path string, mode int) (fd int, err error) {
+	fixwd()
+	return open(path, mode)
+}
+
+//sys	create(path string, mode int, perm uint32) (fd int, err error)
+func Create(path string, mode int, perm uint32) (fd int, err error) {
+	fixwd()
+	return create(path, mode, perm)
+}
+
+//sys	remove(path string) (err error)
+func Remove(path string) error {
+	fixwd()
+	return remove(path)
+}
+
+//sys	stat(path string, edir []byte) (n int, err error)
+func Stat(path string, edir []byte) (n int, err error) {
+	fixwd()
+	return stat(path, edir)
+}
+
+//sys	bind(name string, old string, flag int) (err error)
+func Bind(name string, old string, flag int) (err error) {
+	fixwd()
+	return bind(name, old, flag)
+}
+
+//sys	mount(fd int, afd int, old string, flag int, aname string) (err error)
+func Mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	fixwd()
+	return mount(fd, afd, old, flag, aname)
+}
+
+//sys	wstat(path string, edir []byte) (err error)
+func Wstat(path string, edir []byte) (err error) {
+	fixwd()
+	return wstat(path, edir)
+}
+
+//sys	chdir(path string) (err error)
+//sys	Dup(oldfd int, newfd int) (fd int, err error)
+//sys	Pread(fd int, p []byte, offset int64) (n int, err error)
+//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
+//sys	Close(fd int) (err error)
+//sys	Fstat(fd int, edir []byte) (n int, err error)
+//sys	Fwstat(fd int, edir []byte) (err error)
diff --git a/vendor/golang.org/x/sys/plan9/zsyscall_plan9_386.go b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_386.go
new file mode 100644
index 000000000..6819bc209
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_386.go
@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,386 syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build plan9,386
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
diff --git a/vendor/golang.org/x/sys/plan9/zsyscall_plan9_amd64.go b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_amd64.go
new file mode 100644
index 000000000..418abbbfc
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_amd64.go
@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,amd64 syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build plan9,amd64
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
diff --git a/vendor/golang.org/x/sys/plan9/zsyscall_plan9_arm.go b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_arm.go
new file mode 100644
index 000000000..3e8a1a58c
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/zsyscall_plan9_arm.go
@@ -0,0 +1,284 @@
+// go run mksyscall.go -l32 -plan9 -tags plan9,arm syscall_plan9.go
+// Code generated by the command above; see README.md. DO NOT EDIT.
+
+// +build plan9,arm
+
+package plan9
+
+import "unsafe"
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func fd2path(fd int, buf []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(buf) > 0 {
+		_p0 = unsafe.Pointer(&buf[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FD2PATH, uintptr(fd), uintptr(_p0), uintptr(len(buf)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func pipe(p *[2]int32) (err error) {
+	r0, _, e1 := Syscall(SYS_PIPE, uintptr(unsafe.Pointer(p)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func await(s []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(s) > 0 {
+		_p0 = unsafe.Pointer(&s[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_AWAIT, uintptr(_p0), uintptr(len(s)), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func open(path string, mode int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_OPEN, uintptr(unsafe.Pointer(_p0)), uintptr(mode), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func create(path string, mode int, perm uint32) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CREATE, uintptr(unsafe.Pointer(_p0)), uintptr(mode), uintptr(perm))
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func remove(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_REMOVE, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func stat(path string, edir []byte) (n int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_STAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func bind(name string, old string, flag int) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(name)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_BIND, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), uintptr(flag))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func mount(fd int, afd int, old string, flag int, aname string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(old)
+	if err != nil {
+		return
+	}
+	var _p1 *byte
+	_p1, err = BytePtrFromString(aname)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall6(SYS_MOUNT, uintptr(fd), uintptr(afd), uintptr(unsafe.Pointer(_p0)), uintptr(flag), uintptr(unsafe.Pointer(_p1)), 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func wstat(path string, edir []byte) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	var _p1 unsafe.Pointer
+	if len(edir) > 0 {
+		_p1 = unsafe.Pointer(&edir[0])
+	} else {
+		_p1 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_WSTAT, uintptr(unsafe.Pointer(_p0)), uintptr(_p1), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func chdir(path string) (err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(path)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_CHDIR, uintptr(unsafe.Pointer(_p0)), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Dup(oldfd int, newfd int) (fd int, err error) {
+	r0, _, e1 := Syscall(SYS_DUP, uintptr(oldfd), uintptr(newfd), 0)
+	fd = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pread(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PREAD, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(p) > 0 {
+		_p0 = unsafe.Pointer(&p[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall6(SYS_PWRITE, uintptr(fd), uintptr(_p0), uintptr(len(p)), uintptr(offset), uintptr(offset>>32), 0)
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Close(fd int) (err error) {
+	r0, _, e1 := Syscall(SYS_CLOSE, uintptr(fd), 0, 0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fstat(fd int, edir []byte) (n int, err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	n = int(r0)
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fwstat(fd int, edir []byte) (err error) {
+	var _p0 unsafe.Pointer
+	if len(edir) > 0 {
+		_p0 = unsafe.Pointer(&edir[0])
+	} else {
+		_p0 = unsafe.Pointer(&_zero)
+	}
+	r0, _, e1 := Syscall(SYS_FWSTAT, uintptr(fd), uintptr(_p0), uintptr(len(edir)))
+	if int32(r0) == -1 {
+		err = e1
+	}
+	return
+}
diff --git a/vendor/golang.org/x/sys/plan9/zsysnum_plan9.go b/vendor/golang.org/x/sys/plan9/zsysnum_plan9.go
new file mode 100644
index 000000000..22e8abd43
--- /dev/null
+++ b/vendor/golang.org/x/sys/plan9/zsysnum_plan9.go
@@ -0,0 +1,49 @@
+// mksysnum_plan9.sh /opt/plan9/sys/src/libc/9syscall/sys.h
+// MACHINE GENERATED BY THE ABOVE COMMAND; DO NOT EDIT
+
+package plan9
+
+const (
+	SYS_SYSR1       = 0
+	SYS_BIND        = 2
+	SYS_CHDIR       = 3
+	SYS_CLOSE       = 4
+	SYS_DUP         = 5
+	SYS_ALARM       = 6
+	SYS_EXEC        = 7
+	SYS_EXITS       = 8
+	SYS_FAUTH       = 10
+	SYS_SEGBRK      = 12
+	SYS_OPEN        = 14
+	SYS_OSEEK       = 16
+	SYS_SLEEP       = 17
+	SYS_RFORK       = 19
+	SYS_PIPE        = 21
+	SYS_CREATE      = 22
+	SYS_FD2PATH     = 23
+	SYS_BRK_        = 24
+	SYS_REMOVE      = 25
+	SYS_NOTIFY      = 28
+	SYS_NOTED       = 29
+	SYS_SEGATTACH   = 30
+	SYS_SEGDETACH   = 31
+	SYS_SEGFREE     = 32
+	SYS_SEGFLUSH    = 33
+	SYS_RENDEZVOUS  = 34
+	SYS_UNMOUNT     = 35
+	SYS_SEMACQUIRE  = 37
+	SYS_SEMRELEASE  = 38
+	SYS_SEEK        = 39
+	SYS_FVERSION    = 40
+	SYS_ERRSTR      = 41
+	SYS_STAT        = 42
+	SYS_FSTAT       = 43
+	SYS_WSTAT       = 44
+	SYS_FWSTAT      = 45
+	SYS_MOUNT       = 46
+	SYS_AWAIT       = 47
+	SYS_PREAD       = 50
+	SYS_PWRITE      = 51
+	SYS_TSEMACQUIRE = 52
+	SYS_NSEC        = 53
+)
diff --git a/vendor/golang.org/x/term/AUTHORS b/vendor/golang.org/x/term/AUTHORS
new file mode 100644
index 000000000..15167cd74
--- /dev/null
+++ b/vendor/golang.org/x/term/AUTHORS
@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at http://tip.golang.org/AUTHORS.
diff --git a/vendor/golang.org/x/term/CONTRIBUTING.md b/vendor/golang.org/x/term/CONTRIBUTING.md
new file mode 100644
index 000000000..d0485e887
--- /dev/null
+++ b/vendor/golang.org/x/term/CONTRIBUTING.md
@@ -0,0 +1,26 @@
+# Contributing to Go
+
+Go is an open source project.
+
+It is the work of hundreds of contributors. We appreciate your help!
+
+## Filing issues
+
+When [filing an issue](https://golang.org/issue/new), make sure to answer these five questions:
+
+1.  What version of Go are you using (`go version`)?
+2.  What operating system and processor architecture are you using?
+3.  What did you do?
+4.  What did you expect to see?
+5.  What did you see instead?
+
+General questions should go to the [golang-nuts mailing list](https://groups.google.com/group/golang-nuts) instead of the issue tracker.
+The gophers there will answer or ask you to file an issue if you've tripped over a bug.
+
+## Contributing code
+
+Please read the [Contribution Guidelines](https://golang.org/doc/contribute.html)
+before sending patches.
+
+Unless otherwise noted, the Go source files are distributed under
+the BSD-style license found in the LICENSE file.
diff --git a/vendor/golang.org/x/term/CONTRIBUTORS b/vendor/golang.org/x/term/CONTRIBUTORS
new file mode 100644
index 000000000..1c4577e96
--- /dev/null
+++ b/vendor/golang.org/x/term/CONTRIBUTORS
@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at http://tip.golang.org/CONTRIBUTORS.
diff --git a/vendor/golang.org/x/term/LICENSE b/vendor/golang.org/x/term/LICENSE
new file mode 100644
index 000000000..6a66aea5e
--- /dev/null
+++ b/vendor/golang.org/x/term/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/golang.org/x/term/PATENTS b/vendor/golang.org/x/term/PATENTS
new file mode 100644
index 000000000..733099041
--- /dev/null
+++ b/vendor/golang.org/x/term/PATENTS
@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.
diff --git a/vendor/golang.org/x/term/README.md b/vendor/golang.org/x/term/README.md
new file mode 100644
index 000000000..e0f390cb2
--- /dev/null
+++ b/vendor/golang.org/x/term/README.md
@@ -0,0 +1,17 @@
+# Go terminal/console support
+
+This repository provides Go terminal and console support packages.
+
+## Download/Install
+
+The easiest way to install is to run `go get -u golang.org/x/term`. You can
+also manually git clone the repository to `$GOPATH/src/golang.org/x/term`.
+
+## Report Issues / Send Patches
+
+This repository uses Gerrit for code changes. To learn how to submit changes to
+this repository, see https://golang.org/doc/contribute.html.
+
+The main issue tracker for the term repository is located at
+https://github.com/golang/go/issues. Prefix your issue with "x/term:" in the
+subject line, so it is easy to find.
diff --git a/vendor/golang.org/x/term/go.mod b/vendor/golang.org/x/term/go.mod
new file mode 100644
index 000000000..d45f52851
--- /dev/null
+++ b/vendor/golang.org/x/term/go.mod
@@ -0,0 +1,5 @@
+module golang.org/x/term
+
+go 1.11
+
+require golang.org/x/sys v0.0.0-20201119102817-f84b799fce68
diff --git a/vendor/golang.org/x/term/go.sum b/vendor/golang.org/x/term/go.sum
new file mode 100644
index 000000000..de9e09c65
--- /dev/null
+++ b/vendor/golang.org/x/term/go.sum
@@ -0,0 +1,2 @@
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68 h1:nxC68pudNYkKU6jWhgrqdreuFiOQWj1Fs7T3VrH4Pjw=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_plan9.go b/vendor/golang.org/x/term/term.go
index 9317ac7ed..69931cc84 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_plan9.go
+++ b/vendor/golang.org/x/term/term.go
@@ -1,8 +1,8 @@
-// Copyright 2016 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package terminal provides support functions for dealing with terminals, as
+// Package term provides support functions for dealing with terminals, as
 // commonly found on UNIX systems.
 //
 // Putting a terminal into raw mode is the most common requirement:
@@ -12,47 +12,47 @@
 // 	        panic(err)
 // 	}
 // 	defer terminal.Restore(0, oldState)
-package terminal
+package term
 
-import (
-	"fmt"
-	"runtime"
-)
-
-type State struct{}
+// State contains the state of a terminal.
+type State struct {
+	state
+}
 
 // IsTerminal returns whether the given file descriptor is a terminal.
 func IsTerminal(fd int) bool {
-	return false
+	return isTerminal(fd)
 }
 
-// MakeRaw put the terminal connected to the given file descriptor into raw
+// MakeRaw puts the terminal connected to the given file descriptor into raw
 // mode and returns the previous state of the terminal so that it can be
 // restored.
 func MakeRaw(fd int) (*State, error) {
-	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+	return makeRaw(fd)
 }
 
 // GetState returns the current state of a terminal which may be useful to
 // restore the terminal after a signal.
 func GetState(fd int) (*State, error) {
-	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+	return getState(fd)
 }
 
 // Restore restores the terminal connected to the given file descriptor to a
 // previous state.
-func Restore(fd int, state *State) error {
-	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+func Restore(fd int, oldState *State) error {
+	return restore(fd, oldState)
 }
 
-// GetSize returns the dimensions of the given terminal.
+// GetSize returns the visible dimensions of the given terminal.
+//
+// These dimensions don't include any scrollback buffer height.
 func GetSize(fd int) (width, height int, err error) {
-	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+	return getSize(fd)
 }
 
 // ReadPassword reads a line of input from a terminal without local echo.  This
 // is commonly used for inputting passwords and other sensitive data. The slice
 // returned does not include the \n.
 func ReadPassword(fd int) ([]byte, error) {
-	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+	return readPassword(fd)
 }
diff --git a/vendor/golang.org/x/term/term_plan9.go b/vendor/golang.org/x/term/term_plan9.go
new file mode 100644
index 000000000..21afa55cd
--- /dev/null
+++ b/vendor/golang.org/x/term/term_plan9.go
@@ -0,0 +1,42 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import (
+	"fmt"
+	"runtime"
+
+	"golang.org/x/sys/plan9"
+)
+
+type state struct{}
+
+func isTerminal(fd int) bool {
+	path, err := plan9.Fd2path(fd)
+	if err != nil {
+		return false
+	}
+	return path == "/dev/cons" || path == "/mnt/term/dev/cons"
+}
+
+func makeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func readPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_solaris.go b/vendor/golang.org/x/term/term_solaris.go
index 3d5f06a9f..b9da29744 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_solaris.go
+++ b/vendor/golang.org/x/term/term_solaris.go
@@ -1,32 +1,27 @@
-// Copyright 2015 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build solaris
-
-package terminal // import "golang.org/x/crypto/ssh/terminal"
+package term
 
 import (
-	"golang.org/x/sys/unix"
 	"io"
 	"syscall"
+
+	"golang.org/x/sys/unix"
 )
 
 // State contains the state of a terminal.
-type State struct {
+type state struct {
 	termios unix.Termios
 }
 
-// IsTerminal returns whether the given file descriptor is a terminal.
-func IsTerminal(fd int) bool {
+func isTerminal(fd int) bool {
 	_, err := unix.IoctlGetTermio(fd, unix.TCGETA)
 	return err == nil
 }
 
-// ReadPassword reads a line of input from a terminal without local echo.  This
-// is commonly used for inputting passwords and other sensitive data. The slice
-// returned does not include the \n.
-func ReadPassword(fd int) ([]byte, error) {
+func readPassword(fd int) ([]byte, error) {
 	// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
 	val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
 	if err != nil {
@@ -70,17 +65,14 @@ func ReadPassword(fd int) ([]byte, error) {
 	return ret, nil
 }
 
-// MakeRaw puts the terminal connected to the given file descriptor into raw
-// mode and returns the previous state of the terminal so that it can be
-// restored.
-// see http://cr.illumos.org/~webrev/andy_js/1060/
-func MakeRaw(fd int) (*State, error) {
+func makeRaw(fd int) (*State, error) {
+	// see http://cr.illumos.org/~webrev/andy_js/1060/
 	termios, err := unix.IoctlGetTermios(fd, unix.TCGETS)
 	if err != nil {
 		return nil, err
 	}
 
-	oldState := State{termios: *termios}
+	oldState := State{state{termios: *termios}}
 
 	termios.Iflag &^= unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON
 	termios.Oflag &^= unix.OPOST
@@ -97,25 +89,20 @@ func MakeRaw(fd int) (*State, error) {
 	return &oldState, nil
 }
 
-// Restore restores the terminal connected to the given file descriptor to a
-// previous state.
-func Restore(fd int, oldState *State) error {
+func restore(fd int, oldState *State) error {
 	return unix.IoctlSetTermios(fd, unix.TCSETS, &oldState.termios)
 }
 
-// GetState returns the current state of a terminal which may be useful to
-// restore the terminal after a signal.
-func GetState(fd int) (*State, error) {
+func getState(fd int) (*State, error) {
 	termios, err := unix.IoctlGetTermios(fd, unix.TCGETS)
 	if err != nil {
 		return nil, err
 	}
 
-	return &State{termios: *termios}, nil
+	return &State{state{termios: *termios}}, nil
 }
 
-// GetSize returns the dimensions of the given terminal.
-func GetSize(fd int) (width, height int, err error) {
+func getSize(fd int) (width, height int, err error) {
 	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
 	if err != nil {
 		return 0, 0, err
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util.go b/vendor/golang.org/x/term/term_unix.go
index 391104084..4c60e457d 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util.go
+++ b/vendor/golang.org/x/term/term_unix.go
@@ -1,46 +1,31 @@
-// Copyright 2011 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix darwin dragonfly freebsd linux,!appengine netbsd openbsd
+// +build aix darwin dragonfly freebsd linux netbsd openbsd zos
 
-// Package terminal provides support functions for dealing with terminals, as
-// commonly found on UNIX systems.
-//
-// Putting a terminal into raw mode is the most common requirement:
-//
-// 	oldState, err := terminal.MakeRaw(0)
-// 	if err != nil {
-// 	        panic(err)
-// 	}
-// 	defer terminal.Restore(0, oldState)
-package terminal // import "golang.org/x/crypto/ssh/terminal"
+package term
 
 import (
 	"golang.org/x/sys/unix"
 )
 
-// State contains the state of a terminal.
-type State struct {
+type state struct {
 	termios unix.Termios
 }
 
-// IsTerminal returns whether the given file descriptor is a terminal.
-func IsTerminal(fd int) bool {
+func isTerminal(fd int) bool {
 	_, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
 	return err == nil
 }
 
-// MakeRaw put the terminal connected to the given file descriptor into raw
-// mode and returns the previous state of the terminal so that it can be
-// restored.
-func MakeRaw(fd int) (*State, error) {
+func makeRaw(fd int) (*State, error) {
 	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
 	if err != nil {
 		return nil, err
 	}
 
-	oldState := State{termios: *termios}
+	oldState := State{state{termios: *termios}}
 
 	// This attempts to replicate the behaviour documented for cfmakeraw in
 	// the termios(3) manpage.
@@ -58,25 +43,20 @@ func MakeRaw(fd int) (*State, error) {
 	return &oldState, nil
 }
 
-// GetState returns the current state of a terminal which may be useful to
-// restore the terminal after a signal.
-func GetState(fd int) (*State, error) {
+func getState(fd int) (*State, error) {
 	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
 	if err != nil {
 		return nil, err
 	}
 
-	return &State{termios: *termios}, nil
+	return &State{state{termios: *termios}}, nil
 }
 
-// Restore restores the terminal connected to the given file descriptor to a
-// previous state.
-func Restore(fd int, state *State) error {
+func restore(fd int, state *State) error {
 	return unix.IoctlSetTermios(fd, ioctlWriteTermios, &state.termios)
 }
 
-// GetSize returns the dimensions of the given terminal.
-func GetSize(fd int) (width, height int, err error) {
+func getSize(fd int) (width, height int, err error) {
 	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
 	if err != nil {
 		return -1, -1, err
@@ -91,10 +71,7 @@ func (r passwordReader) Read(buf []byte) (int, error) {
 	return unix.Read(int(r), buf)
 }
 
-// ReadPassword reads a line of input from a terminal without local echo.  This
-// is commonly used for inputting passwords and other sensitive data. The slice
-// returned does not include the \n.
-func ReadPassword(fd int) ([]byte, error) {
+func readPassword(fd int) ([]byte, error) {
 	termios, err := unix.IoctlGetTermios(fd, ioctlReadTermios)
 	if err != nil {
 		return nil, err
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_linux.go b/vendor/golang.org/x/term/term_unix_aix.go
index 5fadfe8a1..2d5efd26a 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_linux.go
+++ b/vendor/golang.org/x/term/term_unix_aix.go
@@ -1,8 +1,8 @@
-// Copyright 2013 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package terminal
+package term
 
 import "golang.org/x/sys/unix"
 
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_bsd.go b/vendor/golang.org/x/term/term_unix_bsd.go
index cb23a5904..3342be00b 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_bsd.go
+++ b/vendor/golang.org/x/term/term_unix_bsd.go
@@ -4,7 +4,7 @@
 
 // +build darwin dragonfly freebsd netbsd openbsd
 
-package terminal
+package term
 
 import "golang.org/x/sys/unix"
 
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_aix.go b/vendor/golang.org/x/term/term_unix_linux.go
index dfcd62785..2d5efd26a 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_aix.go
+++ b/vendor/golang.org/x/term/term_unix_linux.go
@@ -1,10 +1,8 @@
-// Copyright 2018 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build aix
-
-package terminal
+package term
 
 import "golang.org/x/sys/unix"
 
diff --git a/vendor/golang.org/x/term/term_unix_zos.go b/vendor/golang.org/x/term/term_unix_zos.go
new file mode 100644
index 000000000..b85ab8998
--- /dev/null
+++ b/vendor/golang.org/x/term/term_unix_zos.go
@@ -0,0 +1,10 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+const ioctlWriteTermios = unix.TCSETS
diff --git a/vendor/golang.org/x/term/term_unsupported.go b/vendor/golang.org/x/term/term_unsupported.go
new file mode 100644
index 000000000..8b5d1bad0
--- /dev/null
+++ b/vendor/golang.org/x/term/term_unsupported.go
@@ -0,0 +1,38 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !aix,!darwin,!dragonfly,!freebsd,!linux,!netbsd,!openbsd,!zos,!windows,!solaris,!plan9
+
+package term
+
+import (
+	"fmt"
+	"runtime"
+)
+
+type state struct{}
+
+func isTerminal(fd int) bool {
+	return false
+}
+
+func makeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func getSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func readPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
diff --git a/vendor/golang.org/x/crypto/ssh/terminal/util_windows.go b/vendor/golang.org/x/term/term_windows.go
index f614e9cb6..465f56060 100644
--- a/vendor/golang.org/x/crypto/ssh/terminal/util_windows.go
+++ b/vendor/golang.org/x/term/term_windows.go
@@ -1,20 +1,8 @@
-// Copyright 2011 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build windows
-
-// Package terminal provides support functions for dealing with terminals, as
-// commonly found on UNIX systems.
-//
-// Putting a terminal into raw mode is the most common requirement:
-//
-// 	oldState, err := terminal.MakeRaw(0)
-// 	if err != nil {
-// 	        panic(err)
-// 	}
-// 	defer terminal.Restore(0, oldState)
-package terminal
+package term
 
 import (
 	"os"
@@ -22,21 +10,17 @@ import (
 	"golang.org/x/sys/windows"
 )
 
-type State struct {
+type state struct {
 	mode uint32
 }
 
-// IsTerminal returns whether the given file descriptor is a terminal.
-func IsTerminal(fd int) bool {
+func isTerminal(fd int) bool {
 	var st uint32
 	err := windows.GetConsoleMode(windows.Handle(fd), &st)
 	return err == nil
 }
 
-// MakeRaw put the terminal connected to the given file descriptor into raw
-// mode and returns the previous state of the terminal so that it can be
-// restored.
-func MakeRaw(fd int) (*State, error) {
+func makeRaw(fd int) (*State, error) {
 	var st uint32
 	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
 		return nil, err
@@ -45,29 +29,22 @@ func MakeRaw(fd int) (*State, error) {
 	if err := windows.SetConsoleMode(windows.Handle(fd), raw); err != nil {
 		return nil, err
 	}
-	return &State{st}, nil
+	return &State{state{st}}, nil
 }
 
-// GetState returns the current state of a terminal which may be useful to
-// restore the terminal after a signal.
-func GetState(fd int) (*State, error) {
+func getState(fd int) (*State, error) {
 	var st uint32
 	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
 		return nil, err
 	}
-	return &State{st}, nil
+	return &State{state{st}}, nil
 }
 
-// Restore restores the terminal connected to the given file descriptor to a
-// previous state.
-func Restore(fd int, state *State) error {
+func restore(fd int, state *State) error {
 	return windows.SetConsoleMode(windows.Handle(fd), state.mode)
 }
 
-// GetSize returns the visible dimensions of the given terminal.
-//
-// These dimensions don't include any scrollback buffer height.
-func GetSize(fd int) (width, height int, err error) {
+func getSize(fd int) (width, height int, err error) {
 	var info windows.ConsoleScreenBufferInfo
 	if err := windows.GetConsoleScreenBufferInfo(windows.Handle(fd), &info); err != nil {
 		return 0, 0, err
@@ -75,10 +52,7 @@ func GetSize(fd int) (width, height int, err error) {
 	return int(info.Window.Right - info.Window.Left + 1), int(info.Window.Bottom - info.Window.Top + 1), nil
 }
 
-// ReadPassword reads a line of input from a terminal without local echo.  This
-// is commonly used for inputting passwords and other sensitive data. The slice
-// returned does not include the \n.
-func ReadPassword(fd int) ([]byte, error) {
+func readPassword(fd int) ([]byte, error) {
 	var st uint32
 	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
 		return nil, err
diff --git a/vendor/golang.org/x/term/terminal.go b/vendor/golang.org/x/term/terminal.go
new file mode 100644
index 000000000..535ab8257
--- /dev/null
+++ b/vendor/golang.org/x/term/terminal.go
@@ -0,0 +1,987 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package term
+
+import (
+	"bytes"
+	"io"
+	"runtime"
+	"strconv"
+	"sync"
+	"unicode/utf8"
+)
+
+// EscapeCodes contains escape sequences that can be written to the terminal in
+// order to achieve different styles of text.
+type EscapeCodes struct {
+	// Foreground colors
+	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
+
+	// Reset all attributes
+	Reset []byte
+}
+
+var vt100EscapeCodes = EscapeCodes{
+	Black:   []byte{keyEscape, '[', '3', '0', 'm'},
+	Red:     []byte{keyEscape, '[', '3', '1', 'm'},
+	Green:   []byte{keyEscape, '[', '3', '2', 'm'},
+	Yellow:  []byte{keyEscape, '[', '3', '3', 'm'},
+	Blue:    []byte{keyEscape, '[', '3', '4', 'm'},
+	Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
+	Cyan:    []byte{keyEscape, '[', '3', '6', 'm'},
+	White:   []byte{keyEscape, '[', '3', '7', 'm'},
+
+	Reset: []byte{keyEscape, '[', '0', 'm'},
+}
+
+// Terminal contains the state for running a VT100 terminal that is capable of
+// reading lines of input.
+type Terminal struct {
+	// AutoCompleteCallback, if non-null, is called for each keypress with
+	// the full input line and the current position of the cursor (in
+	// bytes, as an index into |line|). If it returns ok=false, the key
+	// press is processed normally. Otherwise it returns a replacement line
+	// and the new cursor position.
+	AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
+
+	// Escape contains a pointer to the escape codes for this terminal.
+	// It's always a valid pointer, although the escape codes themselves
+	// may be empty if the terminal doesn't support them.
+	Escape *EscapeCodes
+
+	// lock protects the terminal and the state in this object from
+	// concurrent processing of a key press and a Write() call.
+	lock sync.Mutex
+
+	c      io.ReadWriter
+	prompt []rune
+
+	// line is the current line being entered.
+	line []rune
+	// pos is the logical position of the cursor in line
+	pos int
+	// echo is true if local echo is enabled
+	echo bool
+	// pasteActive is true iff there is a bracketed paste operation in
+	// progress.
+	pasteActive bool
+
+	// cursorX contains the current X value of the cursor where the left
+	// edge is 0. cursorY contains the row number where the first row of
+	// the current line is 0.
+	cursorX, cursorY int
+	// maxLine is the greatest value of cursorY so far.
+	maxLine int
+
+	termWidth, termHeight int
+
+	// outBuf contains the terminal data to be sent.
+	outBuf []byte
+	// remainder contains the remainder of any partial key sequences after
+	// a read. It aliases into inBuf.
+	remainder []byte
+	inBuf     [256]byte
+
+	// history contains previously entered commands so that they can be
+	// accessed with the up and down keys.
+	history stRingBuffer
+	// historyIndex stores the currently accessed history entry, where zero
+	// means the immediately previous entry.
+	historyIndex int
+	// When navigating up and down the history it's possible to return to
+	// the incomplete, initial line. That value is stored in
+	// historyPending.
+	historyPending string
+}
+
+// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
+// a local terminal, that terminal must first have been put into raw mode.
+// prompt is a string that is written at the start of each input line (i.e.
+// "> ").
+func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
+	return &Terminal{
+		Escape:       &vt100EscapeCodes,
+		c:            c,
+		prompt:       []rune(prompt),
+		termWidth:    80,
+		termHeight:   24,
+		echo:         true,
+		historyIndex: -1,
+	}
+}
+
+const (
+	keyCtrlC     = 3
+	keyCtrlD     = 4
+	keyCtrlU     = 21
+	keyEnter     = '\r'
+	keyEscape    = 27
+	keyBackspace = 127
+	keyUnknown   = 0xd800 /* UTF-16 surrogate area */ + iota
+	keyUp
+	keyDown
+	keyLeft
+	keyRight
+	keyAltLeft
+	keyAltRight
+	keyHome
+	keyEnd
+	keyDeleteWord
+	keyDeleteLine
+	keyClearScreen
+	keyPasteStart
+	keyPasteEnd
+)
+
+var (
+	crlf       = []byte{'\r', '\n'}
+	pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
+	pasteEnd   = []byte{keyEscape, '[', '2', '0', '1', '~'}
+)
+
+// bytesToKey tries to parse a key sequence from b. If successful, it returns
+// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
+func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
+	if len(b) == 0 {
+		return utf8.RuneError, nil
+	}
+
+	if !pasteActive {
+		switch b[0] {
+		case 1: // ^A
+			return keyHome, b[1:]
+		case 2: // ^B
+			return keyLeft, b[1:]
+		case 5: // ^E
+			return keyEnd, b[1:]
+		case 6: // ^F
+			return keyRight, b[1:]
+		case 8: // ^H
+			return keyBackspace, b[1:]
+		case 11: // ^K
+			return keyDeleteLine, b[1:]
+		case 12: // ^L
+			return keyClearScreen, b[1:]
+		case 23: // ^W
+			return keyDeleteWord, b[1:]
+		case 14: // ^N
+			return keyDown, b[1:]
+		case 16: // ^P
+			return keyUp, b[1:]
+		}
+	}
+
+	if b[0] != keyEscape {
+		if !utf8.FullRune(b) {
+			return utf8.RuneError, b
+		}
+		r, l := utf8.DecodeRune(b)
+		return r, b[l:]
+	}
+
+	if !pasteActive && len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
+		switch b[2] {
+		case 'A':
+			return keyUp, b[3:]
+		case 'B':
+			return keyDown, b[3:]
+		case 'C':
+			return keyRight, b[3:]
+		case 'D':
+			return keyLeft, b[3:]
+		case 'H':
+			return keyHome, b[3:]
+		case 'F':
+			return keyEnd, b[3:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
+		switch b[5] {
+		case 'C':
+			return keyAltRight, b[6:]
+		case 'D':
+			return keyAltLeft, b[6:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
+		return keyPasteStart, b[6:]
+	}
+
+	if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
+		return keyPasteEnd, b[6:]
+	}
+
+	// If we get here then we have a key that we don't recognise, or a
+	// partial sequence. It's not clear how one should find the end of a
+	// sequence without knowing them all, but it seems that [a-zA-Z~] only
+	// appears at the end of a sequence.
+	for i, c := range b[0:] {
+		if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '~' {
+			return keyUnknown, b[i+1:]
+		}
+	}
+
+	return utf8.RuneError, b
+}
+
+// queue appends data to the end of t.outBuf
+func (t *Terminal) queue(data []rune) {
+	t.outBuf = append(t.outBuf, []byte(string(data))...)
+}
+
+var eraseUnderCursor = []rune{' ', keyEscape, '[', 'D'}
+var space = []rune{' '}
+
+func isPrintable(key rune) bool {
+	isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
+	return key >= 32 && !isInSurrogateArea
+}
+
+// moveCursorToPos appends data to t.outBuf which will move the cursor to the
+// given, logical position in the text.
+func (t *Terminal) moveCursorToPos(pos int) {
+	if !t.echo {
+		return
+	}
+
+	x := visualLength(t.prompt) + pos
+	y := x / t.termWidth
+	x = x % t.termWidth
+
+	up := 0
+	if y < t.cursorY {
+		up = t.cursorY - y
+	}
+
+	down := 0
+	if y > t.cursorY {
+		down = y - t.cursorY
+	}
+
+	left := 0
+	if x < t.cursorX {
+		left = t.cursorX - x
+	}
+
+	right := 0
+	if x > t.cursorX {
+		right = x - t.cursorX
+	}
+
+	t.cursorX = x
+	t.cursorY = y
+	t.move(up, down, left, right)
+}
+
+func (t *Terminal) move(up, down, left, right int) {
+	m := []rune{}
+
+	// 1 unit up can be expressed as ^[[A or ^[A
+	// 5 units up can be expressed as ^[[5A
+
+	if up == 1 {
+		m = append(m, keyEscape, '[', 'A')
+	} else if up > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(up))...)
+		m = append(m, 'A')
+	}
+
+	if down == 1 {
+		m = append(m, keyEscape, '[', 'B')
+	} else if down > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(down))...)
+		m = append(m, 'B')
+	}
+
+	if right == 1 {
+		m = append(m, keyEscape, '[', 'C')
+	} else if right > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(right))...)
+		m = append(m, 'C')
+	}
+
+	if left == 1 {
+		m = append(m, keyEscape, '[', 'D')
+	} else if left > 1 {
+		m = append(m, keyEscape, '[')
+		m = append(m, []rune(strconv.Itoa(left))...)
+		m = append(m, 'D')
+	}
+
+	t.queue(m)
+}
+
+func (t *Terminal) clearLineToRight() {
+	op := []rune{keyEscape, '[', 'K'}
+	t.queue(op)
+}
+
+const maxLineLength = 4096
+
+func (t *Terminal) setLine(newLine []rune, newPos int) {
+	if t.echo {
+		t.moveCursorToPos(0)
+		t.writeLine(newLine)
+		for i := len(newLine); i < len(t.line); i++ {
+			t.writeLine(space)
+		}
+		t.moveCursorToPos(newPos)
+	}
+	t.line = newLine
+	t.pos = newPos
+}
+
+func (t *Terminal) advanceCursor(places int) {
+	t.cursorX += places
+	t.cursorY += t.cursorX / t.termWidth
+	if t.cursorY > t.maxLine {
+		t.maxLine = t.cursorY
+	}
+	t.cursorX = t.cursorX % t.termWidth
+
+	if places > 0 && t.cursorX == 0 {
+		// Normally terminals will advance the current position
+		// when writing a character. But that doesn't happen
+		// for the last character in a line. However, when
+		// writing a character (except a new line) that causes
+		// a line wrap, the position will be advanced two
+		// places.
+		//
+		// So, if we are stopping at the end of a line, we
+		// need to write a newline so that our cursor can be
+		// advanced to the next line.
+		t.outBuf = append(t.outBuf, '\r', '\n')
+	}
+}
+
+func (t *Terminal) eraseNPreviousChars(n int) {
+	if n == 0 {
+		return
+	}
+
+	if t.pos < n {
+		n = t.pos
+	}
+	t.pos -= n
+	t.moveCursorToPos(t.pos)
+
+	copy(t.line[t.pos:], t.line[n+t.pos:])
+	t.line = t.line[:len(t.line)-n]
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+		for i := 0; i < n; i++ {
+			t.queue(space)
+		}
+		t.advanceCursor(n)
+		t.moveCursorToPos(t.pos)
+	}
+}
+
+// countToLeftWord returns then number of characters from the cursor to the
+// start of the previous word.
+func (t *Terminal) countToLeftWord() int {
+	if t.pos == 0 {
+		return 0
+	}
+
+	pos := t.pos - 1
+	for pos > 0 {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos--
+	}
+	for pos > 0 {
+		if t.line[pos] == ' ' {
+			pos++
+			break
+		}
+		pos--
+	}
+
+	return t.pos - pos
+}
+
+// countToRightWord returns then number of characters from the cursor to the
+// start of the next word.
+func (t *Terminal) countToRightWord() int {
+	pos := t.pos
+	for pos < len(t.line) {
+		if t.line[pos] == ' ' {
+			break
+		}
+		pos++
+	}
+	for pos < len(t.line) {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos++
+	}
+	return pos - t.pos
+}
+
+// visualLength returns the number of visible glyphs in s.
+func visualLength(runes []rune) int {
+	inEscapeSeq := false
+	length := 0
+
+	for _, r := range runes {
+		switch {
+		case inEscapeSeq:
+			if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
+				inEscapeSeq = false
+			}
+		case r == '\x1b':
+			inEscapeSeq = true
+		default:
+			length++
+		}
+	}
+
+	return length
+}
+
+// handleKey processes the given key and, optionally, returns a line of text
+// that the user has entered.
+func (t *Terminal) handleKey(key rune) (line string, ok bool) {
+	if t.pasteActive && key != keyEnter {
+		t.addKeyToLine(key)
+		return
+	}
+
+	switch key {
+	case keyBackspace:
+		if t.pos == 0 {
+			return
+		}
+		t.eraseNPreviousChars(1)
+	case keyAltLeft:
+		// move left by a word.
+		t.pos -= t.countToLeftWord()
+		t.moveCursorToPos(t.pos)
+	case keyAltRight:
+		// move right by a word.
+		t.pos += t.countToRightWord()
+		t.moveCursorToPos(t.pos)
+	case keyLeft:
+		if t.pos == 0 {
+			return
+		}
+		t.pos--
+		t.moveCursorToPos(t.pos)
+	case keyRight:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos++
+		t.moveCursorToPos(t.pos)
+	case keyHome:
+		if t.pos == 0 {
+			return
+		}
+		t.pos = 0
+		t.moveCursorToPos(t.pos)
+	case keyEnd:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos = len(t.line)
+		t.moveCursorToPos(t.pos)
+	case keyUp:
+		entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
+		if !ok {
+			return "", false
+		}
+		if t.historyIndex == -1 {
+			t.historyPending = string(t.line)
+		}
+		t.historyIndex++
+		runes := []rune(entry)
+		t.setLine(runes, len(runes))
+	case keyDown:
+		switch t.historyIndex {
+		case -1:
+			return
+		case 0:
+			runes := []rune(t.historyPending)
+			t.setLine(runes, len(runes))
+			t.historyIndex--
+		default:
+			entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
+			if ok {
+				t.historyIndex--
+				runes := []rune(entry)
+				t.setLine(runes, len(runes))
+			}
+		}
+	case keyEnter:
+		t.moveCursorToPos(len(t.line))
+		t.queue([]rune("\r\n"))
+		line = string(t.line)
+		ok = true
+		t.line = t.line[:0]
+		t.pos = 0
+		t.cursorX = 0
+		t.cursorY = 0
+		t.maxLine = 0
+	case keyDeleteWord:
+		// Delete zero or more spaces and then one or more characters.
+		t.eraseNPreviousChars(t.countToLeftWord())
+	case keyDeleteLine:
+		// Delete everything from the current cursor position to the
+		// end of line.
+		for i := t.pos; i < len(t.line); i++ {
+			t.queue(space)
+			t.advanceCursor(1)
+		}
+		t.line = t.line[:t.pos]
+		t.moveCursorToPos(t.pos)
+	case keyCtrlD:
+		// Erase the character under the current position.
+		// The EOF case when the line is empty is handled in
+		// readLine().
+		if t.pos < len(t.line) {
+			t.pos++
+			t.eraseNPreviousChars(1)
+		}
+	case keyCtrlU:
+		t.eraseNPreviousChars(t.pos)
+	case keyClearScreen:
+		// Erases the screen and moves the cursor to the home position.
+		t.queue([]rune("\x1b[2J\x1b[H"))
+		t.queue(t.prompt)
+		t.cursorX, t.cursorY = 0, 0
+		t.advanceCursor(visualLength(t.prompt))
+		t.setLine(t.line, t.pos)
+	default:
+		if t.AutoCompleteCallback != nil {
+			prefix := string(t.line[:t.pos])
+			suffix := string(t.line[t.pos:])
+
+			t.lock.Unlock()
+			newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
+			t.lock.Lock()
+
+			if completeOk {
+				t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
+				return
+			}
+		}
+		if !isPrintable(key) {
+			return
+		}
+		if len(t.line) == maxLineLength {
+			return
+		}
+		t.addKeyToLine(key)
+	}
+	return
+}
+
+// addKeyToLine inserts the given key at the current position in the current
+// line.
+func (t *Terminal) addKeyToLine(key rune) {
+	if len(t.line) == cap(t.line) {
+		newLine := make([]rune, len(t.line), 2*(1+len(t.line)))
+		copy(newLine, t.line)
+		t.line = newLine
+	}
+	t.line = t.line[:len(t.line)+1]
+	copy(t.line[t.pos+1:], t.line[t.pos:])
+	t.line[t.pos] = key
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+	}
+	t.pos++
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) writeLine(line []rune) {
+	for len(line) != 0 {
+		remainingOnLine := t.termWidth - t.cursorX
+		todo := len(line)
+		if todo > remainingOnLine {
+			todo = remainingOnLine
+		}
+		t.queue(line[:todo])
+		t.advanceCursor(visualLength(line[:todo]))
+		line = line[todo:]
+	}
+}
+
+// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
+func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
+	for len(buf) > 0 {
+		i := bytes.IndexByte(buf, '\n')
+		todo := len(buf)
+		if i >= 0 {
+			todo = i
+		}
+
+		var nn int
+		nn, err = w.Write(buf[:todo])
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		buf = buf[todo:]
+
+		if i >= 0 {
+			if _, err = w.Write(crlf); err != nil {
+				return n, err
+			}
+			n++
+			buf = buf[1:]
+		}
+	}
+
+	return n, nil
+}
+
+func (t *Terminal) Write(buf []byte) (n int, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		// This is the easy case: there's nothing on the screen that we
+		// have to move out of the way.
+		return writeWithCRLF(t.c, buf)
+	}
+
+	// We have a prompt and possibly user input on the screen. We
+	// have to clear it first.
+	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
+	t.cursorX = 0
+	t.clearLineToRight()
+
+	for t.cursorY > 0 {
+		t.move(1 /* up */, 0, 0, 0)
+		t.cursorY--
+		t.clearLineToRight()
+	}
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+
+	if n, err = writeWithCRLF(t.c, buf); err != nil {
+		return
+	}
+
+	t.writeLine(t.prompt)
+	if t.echo {
+		t.writeLine(t.line)
+	}
+
+	t.moveCursorToPos(t.pos)
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+	return
+}
+
+// ReadPassword temporarily changes the prompt and reads a password, without
+// echo, from the terminal.
+func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	oldPrompt := t.prompt
+	t.prompt = []rune(prompt)
+	t.echo = false
+
+	line, err = t.readLine()
+
+	t.prompt = oldPrompt
+	t.echo = true
+
+	return
+}
+
+// ReadLine returns a line of input from the terminal.
+func (t *Terminal) ReadLine() (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	return t.readLine()
+}
+
+func (t *Terminal) readLine() (line string, err error) {
+	// t.lock must be held at this point
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		t.writeLine(t.prompt)
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+	}
+
+	lineIsPasted := t.pasteActive
+
+	for {
+		rest := t.remainder
+		lineOk := false
+		for !lineOk {
+			var key rune
+			key, rest = bytesToKey(rest, t.pasteActive)
+			if key == utf8.RuneError {
+				break
+			}
+			if !t.pasteActive {
+				if key == keyCtrlD {
+					if len(t.line) == 0 {
+						return "", io.EOF
+					}
+				}
+				if key == keyCtrlC {
+					return "", io.EOF
+				}
+				if key == keyPasteStart {
+					t.pasteActive = true
+					if len(t.line) == 0 {
+						lineIsPasted = true
+					}
+					continue
+				}
+			} else if key == keyPasteEnd {
+				t.pasteActive = false
+				continue
+			}
+			if !t.pasteActive {
+				lineIsPasted = false
+			}
+			line, lineOk = t.handleKey(key)
+		}
+		if len(rest) > 0 {
+			n := copy(t.inBuf[:], rest)
+			t.remainder = t.inBuf[:n]
+		} else {
+			t.remainder = nil
+		}
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+		if lineOk {
+			if t.echo {
+				t.historyIndex = -1
+				t.history.Add(line)
+			}
+			if lineIsPasted {
+				err = ErrPasteIndicator
+			}
+			return
+		}
+
+		// t.remainder is a slice at the beginning of t.inBuf
+		// containing a partial key sequence
+		readBuf := t.inBuf[len(t.remainder):]
+		var n int
+
+		t.lock.Unlock()
+		n, err = t.c.Read(readBuf)
+		t.lock.Lock()
+
+		if err != nil {
+			return
+		}
+
+		t.remainder = t.inBuf[:n+len(t.remainder)]
+	}
+}
+
+// SetPrompt sets the prompt to be used when reading subsequent lines.
+func (t *Terminal) SetPrompt(prompt string) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	t.prompt = []rune(prompt)
+}
+
+func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
+	// Move cursor to column zero at the start of the line.
+	t.move(t.cursorY, 0, t.cursorX, 0)
+	t.cursorX, t.cursorY = 0, 0
+	t.clearLineToRight()
+	for t.cursorY < numPrevLines {
+		// Move down a line
+		t.move(0, 1, 0, 0)
+		t.cursorY++
+		t.clearLineToRight()
+	}
+	// Move back to beginning.
+	t.move(t.cursorY, 0, 0, 0)
+	t.cursorX, t.cursorY = 0, 0
+
+	t.queue(t.prompt)
+	t.advanceCursor(visualLength(t.prompt))
+	t.writeLine(t.line)
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) SetSize(width, height int) error {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if width == 0 {
+		width = 1
+	}
+
+	oldWidth := t.termWidth
+	t.termWidth, t.termHeight = width, height
+
+	switch {
+	case width == oldWidth:
+		// If the width didn't change then nothing else needs to be
+		// done.
+		return nil
+	case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
+		// If there is nothing on current line and no prompt printed,
+		// just do nothing
+		return nil
+	case width < oldWidth:
+		// Some terminals (e.g. xterm) will truncate lines that were
+		// too long when shinking. Others, (e.g. gnome-terminal) will
+		// attempt to wrap them. For the former, repainting t.maxLine
+		// works great, but that behaviour goes badly wrong in the case
+		// of the latter because they have doubled every full line.
+
+		// We assume that we are working on a terminal that wraps lines
+		// and adjust the cursor position based on every previous line
+		// wrapping and turning into two. This causes the prompt on
+		// xterms to move upwards, which isn't great, but it avoids a
+		// huge mess with gnome-terminal.
+		if t.cursorX >= t.termWidth {
+			t.cursorX = t.termWidth - 1
+		}
+		t.cursorY *= 2
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
+	case width > oldWidth:
+		// If the terminal expands then our position calculations will
+		// be wrong in the future because we think the cursor is
+		// |t.pos| chars into the string, but there will be a gap at
+		// the end of any wrapped line.
+		//
+		// But the position will actually be correct until we move, so
+		// we can move back to the beginning and repaint everything.
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine)
+	}
+
+	_, err := t.c.Write(t.outBuf)
+	t.outBuf = t.outBuf[:0]
+	return err
+}
+
+type pasteIndicatorError struct{}
+
+func (pasteIndicatorError) Error() string {
+	return "terminal: ErrPasteIndicator not correctly handled"
+}
+
+// ErrPasteIndicator may be returned from ReadLine as the error, in addition
+// to valid line data. It indicates that bracketed paste mode is enabled and
+// that the returned line consists only of pasted data. Programs may wish to
+// interpret pasted data more literally than typed data.
+var ErrPasteIndicator = pasteIndicatorError{}
+
+// SetBracketedPasteMode requests that the terminal bracket paste operations
+// with markers. Not all terminals support this but, if it is supported, then
+// enabling this mode will stop any autocomplete callback from running due to
+// pastes. Additionally, any lines that are completely pasted will be returned
+// from ReadLine with the error set to ErrPasteIndicator.
+func (t *Terminal) SetBracketedPasteMode(on bool) {
+	if on {
+		io.WriteString(t.c, "\x1b[?2004h")
+	} else {
+		io.WriteString(t.c, "\x1b[?2004l")
+	}
+}
+
+// stRingBuffer is a ring buffer of strings.
+type stRingBuffer struct {
+	// entries contains max elements.
+	entries []string
+	max     int
+	// head contains the index of the element most recently added to the ring.
+	head int
+	// size contains the number of elements in the ring.
+	size int
+}
+
+func (s *stRingBuffer) Add(a string) {
+	if s.entries == nil {
+		const defaultNumEntries = 100
+		s.entries = make([]string, defaultNumEntries)
+		s.max = defaultNumEntries
+	}
+
+	s.head = (s.head + 1) % s.max
+	s.entries[s.head] = a
+	if s.size < s.max {
+		s.size++
+	}
+}
+
+// NthPreviousEntry returns the value passed to the nth previous call to Add.
+// If n is zero then the immediately prior value is returned, if one, then the
+// next most recent, and so on. If such an element doesn't exist then ok is
+// false.
+func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
+	if n >= s.size {
+		return "", false
+	}
+	index := s.head - n
+	if index < 0 {
+		index += s.max
+	}
+	return s.entries[index], true
+}
+
+// readPasswordLine reads from reader until it finds \n or io.EOF.
+// The slice returned does not include the \n.
+// readPasswordLine also ignores any \r it finds.
+// Windows uses \r as end of line. So, on Windows, readPasswordLine
+// reads until it finds \r and ignores any \n it finds during processing.
+func readPasswordLine(reader io.Reader) ([]byte, error) {
+	var buf [1]byte
+	var ret []byte
+
+	for {
+		n, err := reader.Read(buf[:])
+		if n > 0 {
+			switch buf[0] {
+			case '\b':
+				if len(ret) > 0 {
+					ret = ret[:len(ret)-1]
+				}
+			case '\n':
+				if runtime.GOOS != "windows" {
+					return ret, nil
+				}
+				// otherwise ignore \n
+			case '\r':
+				if runtime.GOOS == "windows" {
+					return ret, nil
+				}
+				// otherwise ignore \r
+			default:
+				ret = append(ret, buf[0])
+			}
+			continue
+		}
+		if err != nil {
+			if err == io.EOF && len(ret) > 0 {
+				return ret, nil
+			}
+			return ret, err
+		}
+	}
+}