diff --git a/vendor/github.com/coreos/etcd/pkg/adt/README.md b/vendor/github.com/coreos/etcd/pkg/adt/README.md
new file mode 100644
index 0000000..a2089cd
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/adt/README.md
@@ -0,0 +1,48 @@
+
+## Red-Black Tree
+
+*"Introduction to Algorithms" (Cormen et al, 3rd ed.), Chapter 13*
+
+1. Every node is either red or black.
+2. The root is black.
+3. Every leaf (NIL) is black.
+4. If a node is red, then both its children are black.
+5. For each node, all simple paths from the node to descendant leaves contain the
+same number of black nodes.
+
+For example,
+
+```go
+import (
+    "fmt"
+
+    "go.etcd.io/etcd/pkg/adt"
+)
+
+func main() {
+    ivt := adt.NewIntervalTree()
+    ivt.Insert(NewInt64Interval(510, 511), 0)
+    ivt.Insert(NewInt64Interval(82, 83), 0)
+    ivt.Insert(NewInt64Interval(830, 831), 0)
+    ...
+```
+
+After inserting the values `510`, `82`, `830`, `11`, `383`, `647`, `899`, `261`, `410`, `514`, `815`, `888`, `972`, `238`, `292`, `953`.
+
+![red-black-tree-01-insertion.png](img/red-black-tree-01-insertion.png)
+
+Deleting the node `514` should not trigger any rebalancing:
+
+![red-black-tree-02-delete-514.png](img/red-black-tree-02-delete-514.png)
+
+Deleting the node `11` triggers multiple rotates for rebalancing:
+
+![red-black-tree-03-delete-11.png](img/red-black-tree-03-delete-11.png)
+![red-black-tree-04-delete-11.png](img/red-black-tree-04-delete-11.png)
+![red-black-tree-05-delete-11.png](img/red-black-tree-05-delete-11.png)
+![red-black-tree-06-delete-11.png](img/red-black-tree-06-delete-11.png)
+![red-black-tree-07-delete-11.png](img/red-black-tree-07-delete-11.png)
+![red-black-tree-08-delete-11.png](img/red-black-tree-08-delete-11.png)
+![red-black-tree-09-delete-11.png](img/red-black-tree-09-delete-11.png)
+
+Try yourself at https://www.cs.usfca.edu/~galles/visualization/RedBlack.html.
diff --git a/vendor/github.com/coreos/etcd/pkg/adt/doc.go b/vendor/github.com/coreos/etcd/pkg/adt/doc.go
new file mode 100644
index 0000000..1a95591
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/adt/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package adt implements useful abstract data types.
+package adt
diff --git a/vendor/github.com/coreos/etcd/pkg/adt/interval_tree.go b/vendor/github.com/coreos/etcd/pkg/adt/interval_tree.go
new file mode 100644
index 0000000..2e5b2dd
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/adt/interval_tree.go
@@ -0,0 +1,951 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package adt
+
+import (
+	"bytes"
+	"fmt"
+	"math"
+	"strings"
+)
+
+// Comparable is an interface for trichotomic comparisons.
+type Comparable interface {
+	// Compare gives the result of a 3-way comparison
+	// a.Compare(b) = 1 => a > b
+	// a.Compare(b) = 0 => a == b
+	// a.Compare(b) = -1 => a < b
+	Compare(c Comparable) int
+}
+
+type rbcolor int
+
+const (
+	black rbcolor = iota
+	red
+)
+
+func (c rbcolor) String() string {
+	switch c {
+	case black:
+		return "black"
+	case red:
+		return "black"
+	default:
+		panic(fmt.Errorf("unknown color %d", c))
+	}
+}
+
+// Interval implements a Comparable interval [begin, end)
+// TODO: support different sorts of intervals: (a,b), [a,b], (a, b]
+type Interval struct {
+	Begin Comparable
+	End   Comparable
+}
+
+// Compare on an interval gives == if the interval overlaps.
+func (ivl *Interval) Compare(c Comparable) int {
+	ivl2 := c.(*Interval)
+	ivbCmpBegin := ivl.Begin.Compare(ivl2.Begin)
+	ivbCmpEnd := ivl.Begin.Compare(ivl2.End)
+	iveCmpBegin := ivl.End.Compare(ivl2.Begin)
+
+	// ivl is left of ivl2
+	if ivbCmpBegin < 0 && iveCmpBegin <= 0 {
+		return -1
+	}
+
+	// iv is right of iv2
+	if ivbCmpEnd >= 0 {
+		return 1
+	}
+
+	return 0
+}
+
+type intervalNode struct {
+	// iv is the interval-value pair entry.
+	iv IntervalValue
+	// max endpoint of all descendent nodes.
+	max Comparable
+	// left and right are sorted by low endpoint of key interval
+	left, right *intervalNode
+	// parent is the direct ancestor of the node
+	parent *intervalNode
+	c      rbcolor
+}
+
+func (x *intervalNode) color(sentinel *intervalNode) rbcolor {
+	if x == sentinel {
+		return black
+	}
+	return x.c
+}
+
+func (x *intervalNode) height(sentinel *intervalNode) int {
+	if x == sentinel {
+		return 0
+	}
+	ld := x.left.height(sentinel)
+	rd := x.right.height(sentinel)
+	if ld < rd {
+		return rd + 1
+	}
+	return ld + 1
+}
+
+func (x *intervalNode) min(sentinel *intervalNode) *intervalNode {
+	for x.left != sentinel {
+		x = x.left
+	}
+	return x
+}
+
+// successor is the next in-order node in the tree
+func (x *intervalNode) successor(sentinel *intervalNode) *intervalNode {
+	if x.right != sentinel {
+		return x.right.min(sentinel)
+	}
+	y := x.parent
+	for y != sentinel && x == y.right {
+		x = y
+		y = y.parent
+	}
+	return y
+}
+
+// updateMax updates the maximum values for a node and its ancestors
+func (x *intervalNode) updateMax(sentinel *intervalNode) {
+	for x != sentinel {
+		oldmax := x.max
+		max := x.iv.Ivl.End
+		if x.left != sentinel && x.left.max.Compare(max) > 0 {
+			max = x.left.max
+		}
+		if x.right != sentinel && x.right.max.Compare(max) > 0 {
+			max = x.right.max
+		}
+		if oldmax.Compare(max) == 0 {
+			break
+		}
+		x.max = max
+		x = x.parent
+	}
+}
+
+type nodeVisitor func(n *intervalNode) bool
+
+// visit will call a node visitor on each node that overlaps the given interval
+func (x *intervalNode) visit(iv *Interval, sentinel *intervalNode, nv nodeVisitor) bool {
+	if x == sentinel {
+		return true
+	}
+	v := iv.Compare(&x.iv.Ivl)
+	switch {
+	case v < 0:
+		if !x.left.visit(iv, sentinel, nv) {
+			return false
+		}
+	case v > 0:
+		maxiv := Interval{x.iv.Ivl.Begin, x.max}
+		if maxiv.Compare(iv) == 0 {
+			if !x.left.visit(iv, sentinel, nv) || !x.right.visit(iv, sentinel, nv) {
+				return false
+			}
+		}
+	default:
+		if !x.left.visit(iv, sentinel, nv) || !nv(x) || !x.right.visit(iv, sentinel, nv) {
+			return false
+		}
+	}
+	return true
+}
+
+// IntervalValue represents a range tree node that contains a range and a value.
+type IntervalValue struct {
+	Ivl Interval
+	Val interface{}
+}
+
+// IntervalTree represents a (mostly) textbook implementation of the
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.) chapter 13 red-black tree
+// and chapter 14.3 interval tree with search supporting "stabbing queries".
+type IntervalTree interface {
+	// Insert adds a node with the given interval into the tree.
+	Insert(ivl Interval, val interface{})
+	// Delete removes the node with the given interval from the tree, returning
+	// true if a node is in fact removed.
+	Delete(ivl Interval) bool
+	// Len gives the number of elements in the tree.
+	Len() int
+	// Height is the number of levels in the tree; one node has height 1.
+	Height() int
+	// MaxHeight is the expected maximum tree height given the number of nodes.
+	MaxHeight() int
+	// Visit calls a visitor function on every tree node intersecting the given interval.
+	// It will visit each interval [x, y) in ascending order sorted on x.
+	Visit(ivl Interval, ivv IntervalVisitor)
+	// Find gets the IntervalValue for the node matching the given interval
+	Find(ivl Interval) *IntervalValue
+	// Intersects returns true if there is some tree node intersecting the given interval.
+	Intersects(iv Interval) bool
+	// Contains returns true if the interval tree's keys cover the entire given interval.
+	Contains(ivl Interval) bool
+	// Stab returns a slice with all elements in the tree intersecting the interval.
+	Stab(iv Interval) []*IntervalValue
+	// Union merges a given interval tree into the receiver.
+	Union(inIvt IntervalTree, ivl Interval)
+}
+
+// NewIntervalTree returns a new interval tree.
+func NewIntervalTree() IntervalTree {
+	sentinel := &intervalNode{
+		iv:     IntervalValue{},
+		max:    nil,
+		left:   nil,
+		right:  nil,
+		parent: nil,
+		c:      black,
+	}
+	return &intervalTree{
+		root:     sentinel,
+		count:    0,
+		sentinel: sentinel,
+	}
+}
+
+type intervalTree struct {
+	root  *intervalNode
+	count int
+
+	// red-black NIL node
+	// use 'sentinel' as a dummy object to simplify boundary conditions
+	// use the sentinel to treat a nil child of a node x as an ordinary node whose parent is x
+	// use one shared sentinel to represent all nil leaves and the root's parent
+	sentinel *intervalNode
+}
+
+// TODO: make this consistent with textbook implementation
+//
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.), chapter 13.4, p324
+//
+//	 0. RB-DELETE(T, z)
+//	 1.
+//	 2. y = z
+//	 3. y-original-color = y.color
+//	 4.
+//	 5. if z.left == T.nil
+//	 6. 	x = z.right
+//	 7. 	RB-TRANSPLANT(T, z, z.right)
+//	 8. else if z.right == T.nil
+//	 9. 	x = z.left
+//	10. 	RB-TRANSPLANT(T, z, z.left)
+//	11. else
+//	12. 	y = TREE-MINIMUM(z.right)
+//	13. 	y-original-color = y.color
+//	14. 	x = y.right
+//	15. 	if y.p == z
+//	16. 		x.p = y
+//	17. 	else
+//	18. 		RB-TRANSPLANT(T, y, y.right)
+//	19. 		y.right = z.right
+//	20. 		y.right.p = y
+//	21. 	RB-TRANSPLANT(T, z, y)
+//	22. 	y.left = z.left
+//	23. 	y.left.p = y
+//	24. 	y.color = z.color
+//	25.
+//	26. if y-original-color == BLACK
+//	27. 	RB-DELETE-FIXUP(T, x)
+
+// Delete removes the node with the given interval from the tree, returning
+// true if a node is in fact removed.
+func (ivt *intervalTree) Delete(ivl Interval) bool {
+	z := ivt.find(ivl)
+	if z == ivt.sentinel {
+		return false
+	}
+
+	y := z
+	if z.left != ivt.sentinel && z.right != ivt.sentinel {
+		y = z.successor(ivt.sentinel)
+	}
+
+	x := ivt.sentinel
+	if y.left != ivt.sentinel {
+		x = y.left
+	} else if y.right != ivt.sentinel {
+		x = y.right
+	}
+
+	x.parent = y.parent
+
+	if y.parent == ivt.sentinel {
+		ivt.root = x
+	} else {
+		if y == y.parent.left {
+			y.parent.left = x
+		} else {
+			y.parent.right = x
+		}
+		y.parent.updateMax(ivt.sentinel)
+	}
+	if y != z {
+		z.iv = y.iv
+		z.updateMax(ivt.sentinel)
+	}
+
+	if y.color(ivt.sentinel) == black {
+		ivt.deleteFixup(x)
+	}
+
+	ivt.count--
+	return true
+}
+
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.), chapter 13.4, p326
+//
+//	 0. RB-DELETE-FIXUP(T, z)
+//	 1.
+//	 2. while x ≠ T.root and x.color == BLACK
+//	 3. 	if x == x.p.left
+//	 4. 		w = x.p.right
+//	 5. 		if w.color == RED
+//	 6. 			w.color = BLACK
+//	 7. 			x.p.color = RED
+//	 8. 			LEFT-ROTATE(T, x, p)
+//	 9. 		if w.left.color == BLACK and w.right.color == BLACK
+//	10. 			w.color = RED
+//	11. 			x = x.p
+//	12. 		else if w.right.color == BLACK
+//	13. 				w.left.color = BLACK
+//	14. 				w.color = RED
+//	15. 				RIGHT-ROTATE(T, w)
+//	16. 				w = w.p.right
+//	17. 			w.color = x.p.color
+//	18. 			x.p.color = BLACK
+//	19. 			LEFT-ROTATE(T, w.p)
+//	20. 			x = T.root
+//	21. 	else
+//	22. 		w = x.p.left
+//	23. 		if w.color == RED
+//	24. 			w.color = BLACK
+//	25. 			x.p.color = RED
+//	26. 			RIGHT-ROTATE(T, x, p)
+//	27. 		if w.right.color == BLACK and w.left.color == BLACK
+//	28. 			w.color = RED
+//	29. 			x = x.p
+//	30. 		else if w.left.color == BLACK
+//	31. 				w.right.color = BLACK
+//	32. 				w.color = RED
+//	33. 				LEFT-ROTATE(T, w)
+//	34. 				w = w.p.left
+//	35. 			w.color = x.p.color
+//	36. 			x.p.color = BLACK
+//	37. 			RIGHT-ROTATE(T, w.p)
+//	38. 			x = T.root
+//	39.
+//	40. x.color = BLACK
+//
+func (ivt *intervalTree) deleteFixup(x *intervalNode) {
+	for x != ivt.root && x.color(ivt.sentinel) == black {
+		if x == x.parent.left { // line 3-20
+			w := x.parent.right
+			if w.color(ivt.sentinel) == red {
+				w.c = black
+				x.parent.c = red
+				ivt.rotateLeft(x.parent)
+				w = x.parent.right
+			}
+			if w == nil {
+				break
+			}
+			if w.left.color(ivt.sentinel) == black && w.right.color(ivt.sentinel) == black {
+				w.c = red
+				x = x.parent
+			} else {
+				if w.right.color(ivt.sentinel) == black {
+					w.left.c = black
+					w.c = red
+					ivt.rotateRight(w)
+					w = x.parent.right
+				}
+				w.c = x.parent.color(ivt.sentinel)
+				x.parent.c = black
+				w.right.c = black
+				ivt.rotateLeft(x.parent)
+				x = ivt.root
+			}
+		} else { // line 22-38
+			// same as above but with left and right exchanged
+			w := x.parent.left
+			if w.color(ivt.sentinel) == red {
+				w.c = black
+				x.parent.c = red
+				ivt.rotateRight(x.parent)
+				w = x.parent.left
+			}
+			if w == nil {
+				break
+			}
+			if w.left.color(ivt.sentinel) == black && w.right.color(ivt.sentinel) == black {
+				w.c = red
+				x = x.parent
+			} else {
+				if w.left.color(ivt.sentinel) == black {
+					w.right.c = black
+					w.c = red
+					ivt.rotateLeft(w)
+					w = x.parent.left
+				}
+				w.c = x.parent.color(ivt.sentinel)
+				x.parent.c = black
+				w.left.c = black
+				ivt.rotateRight(x.parent)
+				x = ivt.root
+			}
+		}
+	}
+
+	if x != nil {
+		x.c = black
+	}
+}
+
+func (ivt *intervalTree) createIntervalNode(ivl Interval, val interface{}) *intervalNode {
+	return &intervalNode{
+		iv:     IntervalValue{ivl, val},
+		max:    ivl.End,
+		c:      red,
+		left:   ivt.sentinel,
+		right:  ivt.sentinel,
+		parent: ivt.sentinel,
+	}
+}
+
+// TODO: make this consistent with textbook implementation
+//
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.), chapter 13.3, p315
+//
+//	 0. RB-INSERT(T, z)
+//	 1.
+//	 2. y = T.nil
+//	 3. x = T.root
+//	 4.
+//	 5. while x ≠ T.nil
+//	 6. 	y = x
+//	 7. 	if z.key < x.key
+//	 8. 		x = x.left
+//	 9. 	else
+//	10. 		x = x.right
+//	11.
+//	12. z.p = y
+//	13.
+//	14. if y == T.nil
+//	15. 	T.root = z
+//	16. else if z.key < y.key
+//	17. 	y.left = z
+//	18. else
+//	19. 	y.right = z
+//	20.
+//	21. z.left = T.nil
+//	22. z.right = T.nil
+//	23. z.color = RED
+//	24.
+//	25. RB-INSERT-FIXUP(T, z)
+
+// Insert adds a node with the given interval into the tree.
+func (ivt *intervalTree) Insert(ivl Interval, val interface{}) {
+	y := ivt.sentinel
+	z := ivt.createIntervalNode(ivl, val)
+	x := ivt.root
+	for x != ivt.sentinel {
+		y = x
+		if z.iv.Ivl.Begin.Compare(x.iv.Ivl.Begin) < 0 {
+			x = x.left
+		} else {
+			x = x.right
+		}
+	}
+
+	z.parent = y
+	if y == ivt.sentinel {
+		ivt.root = z
+	} else {
+		if z.iv.Ivl.Begin.Compare(y.iv.Ivl.Begin) < 0 {
+			y.left = z
+		} else {
+			y.right = z
+		}
+		y.updateMax(ivt.sentinel)
+	}
+	z.c = red
+
+	ivt.insertFixup(z)
+	ivt.count++
+}
+
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.), chapter 13.3, p316
+//
+//	 0. RB-INSERT-FIXUP(T, z)
+//	 1.
+//	 2. while z.p.color == RED
+//	 3. 	if z.p == z.p.p.left
+//	 4. 		y = z.p.p.right
+//	 5. 		if y.color == RED
+//	 6. 			z.p.color = BLACK
+//	 7. 			y.color = BLACK
+//	 8. 			z.p.p.color = RED
+//	 9. 			z = z.p.p
+//	10. 		else if z == z.p.right
+//	11. 				z = z.p
+//	12. 				LEFT-ROTATE(T, z)
+//	13. 			z.p.color = BLACK
+//	14. 			z.p.p.color = RED
+//	15. 			RIGHT-ROTATE(T, z.p.p)
+//	16. 	else
+//	17. 		y = z.p.p.left
+//	18. 		if y.color == RED
+//	19. 			z.p.color = BLACK
+//	20. 			y.color = BLACK
+//	21. 			z.p.p.color = RED
+//	22. 			z = z.p.p
+//	23. 		else if z == z.p.right
+//	24. 				z = z.p
+//	25. 				RIGHT-ROTATE(T, z)
+//	26. 			z.p.color = BLACK
+//	27. 			z.p.p.color = RED
+//	28. 			LEFT-ROTATE(T, z.p.p)
+//	29.
+//	30. T.root.color = BLACK
+//
+func (ivt *intervalTree) insertFixup(z *intervalNode) {
+	for z.parent.color(ivt.sentinel) == red {
+		if z.parent == z.parent.parent.left { // line 3-15
+
+			y := z.parent.parent.right
+			if y.color(ivt.sentinel) == red {
+				y.c = black
+				z.parent.c = black
+				z.parent.parent.c = red
+				z = z.parent.parent
+			} else {
+				if z == z.parent.right {
+					z = z.parent
+					ivt.rotateLeft(z)
+				}
+				z.parent.c = black
+				z.parent.parent.c = red
+				ivt.rotateRight(z.parent.parent)
+			}
+		} else { // line 16-28
+			// same as then with left/right exchanged
+			y := z.parent.parent.left
+			if y.color(ivt.sentinel) == red {
+				y.c = black
+				z.parent.c = black
+				z.parent.parent.c = red
+				z = z.parent.parent
+			} else {
+				if z == z.parent.left {
+					z = z.parent
+					ivt.rotateRight(z)
+				}
+				z.parent.c = black
+				z.parent.parent.c = red
+				ivt.rotateLeft(z.parent.parent)
+			}
+		}
+	}
+
+	// line 30
+	ivt.root.c = black
+}
+
+// rotateLeft moves x so it is left of its right child
+//
+// "Introduction to Algorithms" (Cormen et al, 3rd ed.), chapter 13.2, p313
+//
+//	 0. LEFT-ROTATE(T, x)
+//	 1.
+//	 2. y = x.right
+//	 3. x.right = y.left
+//	 4.
+//	 5. if y.left ≠ T.nil
+//	 6. 	y.left.p = x
+//	 7.
+//	 8. y.p = x.p
+//	 9.
+//	10. if x.p == T.nil
+//	11. 	T.root = y
+//	12. else if x == x.p.left
+//	13. 	x.p.left = y
+//	14. else
+//	15. 	x.p.right = y
+//	16.
+//	17. y.left = x
+//	18. x.p = y
+//
+func (ivt *intervalTree) rotateLeft(x *intervalNode) {
+	// rotateLeft x must have right child
+	if x.right == ivt.sentinel {
+		return
+	}
+
+	// line 2-3
+	y := x.right
+	x.right = y.left
+
+	// line 5-6
+	if y.left != ivt.sentinel {
+		y.left.parent = x
+	}
+	x.updateMax(ivt.sentinel)
+
+	// line 10-15, 18
+	ivt.replaceParent(x, y)
+
+	// line 17
+	y.left = x
+	y.updateMax(ivt.sentinel)
+}
+
+// rotateRight moves x so it is right of its left child
+//
+//	 0. RIGHT-ROTATE(T, x)
+//	 1.
+//	 2. y = x.left
+//	 3. x.left = y.right
+//	 4.
+//	 5. if y.right ≠ T.nil
+//	 6. 	y.right.p = x
+//	 7.
+//	 8. y.p = x.p
+//	 9.
+//	10. if x.p == T.nil
+//	11. 	T.root = y
+//	12. else if x == x.p.right
+//	13. 	x.p.right = y
+//	14. else
+//	15. 	x.p.left = y
+//	16.
+//	17. y.right = x
+//	18. x.p = y
+//
+func (ivt *intervalTree) rotateRight(x *intervalNode) {
+	// rotateRight x must have left child
+	if x.left == ivt.sentinel {
+		return
+	}
+
+	// line 2-3
+	y := x.left
+	x.left = y.right
+
+	// line 5-6
+	if y.right != ivt.sentinel {
+		y.right.parent = x
+	}
+	x.updateMax(ivt.sentinel)
+
+	// line 10-15, 18
+	ivt.replaceParent(x, y)
+
+	// line 17
+	y.right = x
+	y.updateMax(ivt.sentinel)
+}
+
+// replaceParent replaces x's parent with y
+func (ivt *intervalTree) replaceParent(x *intervalNode, y *intervalNode) {
+	y.parent = x.parent
+	if x.parent == ivt.sentinel {
+		ivt.root = y
+	} else {
+		if x == x.parent.left {
+			x.parent.left = y
+		} else {
+			x.parent.right = y
+		}
+		x.parent.updateMax(ivt.sentinel)
+	}
+	x.parent = y
+}
+
+// Len gives the number of elements in the tree
+func (ivt *intervalTree) Len() int { return ivt.count }
+
+// Height is the number of levels in the tree; one node has height 1.
+func (ivt *intervalTree) Height() int { return ivt.root.height(ivt.sentinel) }
+
+// MaxHeight is the expected maximum tree height given the number of nodes
+func (ivt *intervalTree) MaxHeight() int {
+	return int((2 * math.Log2(float64(ivt.Len()+1))) + 0.5)
+}
+
+// IntervalVisitor is used on tree searches; return false to stop searching.
+type IntervalVisitor func(n *IntervalValue) bool
+
+// Visit calls a visitor function on every tree node intersecting the given interval.
+// It will visit each interval [x, y) in ascending order sorted on x.
+func (ivt *intervalTree) Visit(ivl Interval, ivv IntervalVisitor) {
+	ivt.root.visit(&ivl, ivt.sentinel, func(n *intervalNode) bool { return ivv(&n.iv) })
+}
+
+// find the exact node for a given interval
+func (ivt *intervalTree) find(ivl Interval) *intervalNode {
+	ret := ivt.sentinel
+	f := func(n *intervalNode) bool {
+		if n.iv.Ivl != ivl {
+			return true
+		}
+		ret = n
+		return false
+	}
+	ivt.root.visit(&ivl, ivt.sentinel, f)
+	return ret
+}
+
+// Find gets the IntervalValue for the node matching the given interval
+func (ivt *intervalTree) Find(ivl Interval) (ret *IntervalValue) {
+	n := ivt.find(ivl)
+	if n == ivt.sentinel {
+		return nil
+	}
+	return &n.iv
+}
+
+// Intersects returns true if there is some tree node intersecting the given interval.
+func (ivt *intervalTree) Intersects(iv Interval) bool {
+	x := ivt.root
+	for x != ivt.sentinel && iv.Compare(&x.iv.Ivl) != 0 {
+		if x.left != ivt.sentinel && x.left.max.Compare(iv.Begin) > 0 {
+			x = x.left
+		} else {
+			x = x.right
+		}
+	}
+	return x != ivt.sentinel
+}
+
+// Contains returns true if the interval tree's keys cover the entire given interval.
+func (ivt *intervalTree) Contains(ivl Interval) bool {
+	var maxEnd, minBegin Comparable
+
+	isContiguous := true
+	ivt.Visit(ivl, func(n *IntervalValue) bool {
+		if minBegin == nil {
+			minBegin = n.Ivl.Begin
+			maxEnd = n.Ivl.End
+			return true
+		}
+		if maxEnd.Compare(n.Ivl.Begin) < 0 {
+			isContiguous = false
+			return false
+		}
+		if n.Ivl.End.Compare(maxEnd) > 0 {
+			maxEnd = n.Ivl.End
+		}
+		return true
+	})
+
+	return isContiguous && minBegin != nil && maxEnd.Compare(ivl.End) >= 0 && minBegin.Compare(ivl.Begin) <= 0
+}
+
+// Stab returns a slice with all elements in the tree intersecting the interval.
+func (ivt *intervalTree) Stab(iv Interval) (ivs []*IntervalValue) {
+	if ivt.count == 0 {
+		return nil
+	}
+	f := func(n *IntervalValue) bool { ivs = append(ivs, n); return true }
+	ivt.Visit(iv, f)
+	return ivs
+}
+
+// Union merges a given interval tree into the receiver.
+func (ivt *intervalTree) Union(inIvt IntervalTree, ivl Interval) {
+	f := func(n *IntervalValue) bool {
+		ivt.Insert(n.Ivl, n.Val)
+		return true
+	}
+	inIvt.Visit(ivl, f)
+}
+
+type visitedInterval struct {
+	root  Interval
+	left  Interval
+	right Interval
+	color rbcolor
+	depth int
+}
+
+func (vi visitedInterval) String() string {
+	bd := new(strings.Builder)
+	bd.WriteString(fmt.Sprintf("root [%v,%v,%v], left [%v,%v], right [%v,%v], depth %d",
+		vi.root.Begin, vi.root.End, vi.color,
+		vi.left.Begin, vi.left.End,
+		vi.right.Begin, vi.right.End,
+		vi.depth,
+	))
+	return bd.String()
+}
+
+// visitLevel traverses tree in level order.
+// used for testing
+func (ivt *intervalTree) visitLevel() []visitedInterval {
+	if ivt.root == ivt.sentinel {
+		return nil
+	}
+
+	rs := make([]visitedInterval, 0, ivt.Len())
+
+	type pair struct {
+		node  *intervalNode
+		depth int
+	}
+	queue := []pair{{ivt.root, 0}}
+	for len(queue) > 0 {
+		f := queue[0]
+		queue = queue[1:]
+
+		vi := visitedInterval{
+			root:  f.node.iv.Ivl,
+			color: f.node.color(ivt.sentinel),
+			depth: f.depth,
+		}
+		if f.node.left != ivt.sentinel {
+			vi.left = f.node.left.iv.Ivl
+			queue = append(queue, pair{f.node.left, f.depth + 1})
+		}
+		if f.node.right != ivt.sentinel {
+			vi.right = f.node.right.iv.Ivl
+			queue = append(queue, pair{f.node.right, f.depth + 1})
+		}
+
+		rs = append(rs, vi)
+	}
+
+	return rs
+}
+
+type StringComparable string
+
+func (s StringComparable) Compare(c Comparable) int {
+	sc := c.(StringComparable)
+	if s < sc {
+		return -1
+	}
+	if s > sc {
+		return 1
+	}
+	return 0
+}
+
+func NewStringInterval(begin, end string) Interval {
+	return Interval{StringComparable(begin), StringComparable(end)}
+}
+
+func NewStringPoint(s string) Interval {
+	return Interval{StringComparable(s), StringComparable(s + "\x00")}
+}
+
+// StringAffineComparable treats "" as > all other strings
+type StringAffineComparable string
+
+func (s StringAffineComparable) Compare(c Comparable) int {
+	sc := c.(StringAffineComparable)
+
+	if len(s) == 0 {
+		if len(sc) == 0 {
+			return 0
+		}
+		return 1
+	}
+	if len(sc) == 0 {
+		return -1
+	}
+
+	if s < sc {
+		return -1
+	}
+	if s > sc {
+		return 1
+	}
+	return 0
+}
+
+func NewStringAffineInterval(begin, end string) Interval {
+	return Interval{StringAffineComparable(begin), StringAffineComparable(end)}
+}
+
+func NewStringAffinePoint(s string) Interval {
+	return NewStringAffineInterval(s, s+"\x00")
+}
+
+func NewInt64Interval(a int64, b int64) Interval {
+	return Interval{Int64Comparable(a), Int64Comparable(b)}
+}
+
+func newInt64EmptyInterval() Interval {
+	return Interval{Begin: nil, End: nil}
+}
+
+func NewInt64Point(a int64) Interval {
+	return Interval{Int64Comparable(a), Int64Comparable(a + 1)}
+}
+
+type Int64Comparable int64
+
+func (v Int64Comparable) Compare(c Comparable) int {
+	vc := c.(Int64Comparable)
+	cmp := v - vc
+	if cmp < 0 {
+		return -1
+	}
+	if cmp > 0 {
+		return 1
+	}
+	return 0
+}
+
+// BytesAffineComparable treats empty byte arrays as > all other byte arrays
+type BytesAffineComparable []byte
+
+func (b BytesAffineComparable) Compare(c Comparable) int {
+	bc := c.(BytesAffineComparable)
+
+	if len(b) == 0 {
+		if len(bc) == 0 {
+			return 0
+		}
+		return 1
+	}
+	if len(bc) == 0 {
+		return -1
+	}
+
+	return bytes.Compare(b, bc)
+}
+
+func NewBytesAffineInterval(begin, end []byte) Interval {
+	return Interval{BytesAffineComparable(begin), BytesAffineComparable(end)}
+}
+
+func NewBytesAffinePoint(b []byte) Interval {
+	be := make([]byte, len(b)+1)
+	copy(be, b)
+	be[len(b)] = 0
+	return NewBytesAffineInterval(b, be)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/contention/contention.go b/vendor/github.com/coreos/etcd/pkg/contention/contention.go
new file mode 100644
index 0000000..26ce9a2
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/contention/contention.go
@@ -0,0 +1,69 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package contention
+
+import (
+	"sync"
+	"time"
+)
+
+// TimeoutDetector detects routine starvations by
+// observing the actual time duration to finish an action
+// or between two events that should happen in a fixed
+// interval. If the observed duration is longer than
+// the expectation, the detector will report the result.
+type TimeoutDetector struct {
+	mu          sync.Mutex // protects all
+	maxDuration time.Duration
+	// map from event to time
+	// time is the last seen time of the event.
+	records map[uint64]time.Time
+}
+
+// NewTimeoutDetector creates the TimeoutDetector.
+func NewTimeoutDetector(maxDuration time.Duration) *TimeoutDetector {
+	return &TimeoutDetector{
+		maxDuration: maxDuration,
+		records:     make(map[uint64]time.Time),
+	}
+}
+
+// Reset resets the NewTimeoutDetector.
+func (td *TimeoutDetector) Reset() {
+	td.mu.Lock()
+	defer td.mu.Unlock()
+
+	td.records = make(map[uint64]time.Time)
+}
+
+// Observe observes an event for given id. It returns false and exceeded duration
+// if the interval is longer than the expectation.
+func (td *TimeoutDetector) Observe(which uint64) (bool, time.Duration) {
+	td.mu.Lock()
+	defer td.mu.Unlock()
+
+	ok := true
+	now := time.Now()
+	exceed := time.Duration(0)
+
+	if pt, found := td.records[which]; found {
+		exceed = now.Sub(pt) - td.maxDuration
+		if exceed > 0 {
+			ok = false
+		}
+	}
+	td.records[which] = now
+	return ok, exceed
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/contention/doc.go b/vendor/github.com/coreos/etcd/pkg/contention/doc.go
new file mode 100644
index 0000000..daf4522
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/contention/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package contention provides facilities for detecting system contention.
+package contention
diff --git a/vendor/github.com/coreos/etcd/pkg/cors/cors.go b/vendor/github.com/coreos/etcd/pkg/cors/cors.go
new file mode 100644
index 0000000..0c64f16
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/cors/cors.go
@@ -0,0 +1,90 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package cors handles cross-origin HTTP requests (CORS).
+package cors
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"sort"
+	"strings"
+)
+
+type CORSInfo map[string]bool
+
+// Set implements the flag.Value interface to allow users to define a list of CORS origins
+func (ci *CORSInfo) Set(s string) error {
+	m := make(map[string]bool)
+	for _, v := range strings.Split(s, ",") {
+		v = strings.TrimSpace(v)
+		if v == "" {
+			continue
+		}
+		if v != "*" {
+			if _, err := url.Parse(v); err != nil {
+				return fmt.Errorf("Invalid CORS origin: %s", err)
+			}
+		}
+		m[v] = true
+
+	}
+	*ci = CORSInfo(m)
+	return nil
+}
+
+func (ci *CORSInfo) String() string {
+	o := make([]string, 0)
+	for k := range *ci {
+		o = append(o, k)
+	}
+	sort.StringSlice(o).Sort()
+	return strings.Join(o, ",")
+}
+
+// OriginAllowed determines whether the server will allow a given CORS origin.
+func (c CORSInfo) OriginAllowed(origin string) bool {
+	return c["*"] || c[origin]
+}
+
+type CORSHandler struct {
+	Handler http.Handler
+	Info    *CORSInfo
+}
+
+// addHeader adds the correct cors headers given an origin
+func (h *CORSHandler) addHeader(w http.ResponseWriter, origin string) {
+	w.Header().Add("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE")
+	w.Header().Add("Access-Control-Allow-Origin", origin)
+	w.Header().Add("Access-Control-Allow-Headers", "accept, content-type, authorization")
+}
+
+// ServeHTTP adds the correct CORS headers based on the origin and returns immediately
+// with a 200 OK if the method is OPTIONS.
+func (h *CORSHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	// Write CORS header.
+	if h.Info.OriginAllowed("*") {
+		h.addHeader(w, "*")
+	} else if origin := req.Header.Get("Origin"); h.Info.OriginAllowed(origin) {
+		h.addHeader(w, origin)
+	}
+
+	if req.Method == "OPTIONS" {
+		w.WriteHeader(http.StatusOK)
+		return
+	}
+
+	h.Handler.ServeHTTP(w, req)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/cpuutil/doc.go b/vendor/github.com/coreos/etcd/pkg/cpuutil/doc.go
new file mode 100644
index 0000000..0323b2d
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/cpuutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package cpuutil provides facilities for detecting cpu-specific features.
+package cpuutil
diff --git a/vendor/github.com/coreos/etcd/pkg/cpuutil/endian.go b/vendor/github.com/coreos/etcd/pkg/cpuutil/endian.go
new file mode 100644
index 0000000..06c06cd
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/cpuutil/endian.go
@@ -0,0 +1,36 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cpuutil
+
+import (
+	"encoding/binary"
+	"unsafe"
+)
+
+const intWidth int = int(unsafe.Sizeof(0))
+
+var byteOrder binary.ByteOrder
+
+// ByteOrder returns the byte order for the CPU's native endianness.
+func ByteOrder() binary.ByteOrder { return byteOrder }
+
+func init() {
+	i := int(0x1)
+	if v := (*[intWidth]byte)(unsafe.Pointer(&i)); v[0] == 0 {
+		byteOrder = binary.BigEndian
+	} else {
+		byteOrder = binary.LittleEndian
+	}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/crc/crc.go b/vendor/github.com/coreos/etcd/pkg/crc/crc.go
new file mode 100644
index 0000000..4b998a4
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/crc/crc.go
@@ -0,0 +1,43 @@
+// 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.
+
+// Package crc provides utility function for cyclic redundancy check
+// algorithms.
+package crc
+
+import (
+	"hash"
+	"hash/crc32"
+)
+
+// The size of a CRC-32 checksum in bytes.
+const Size = 4
+
+type digest struct {
+	crc uint32
+	tab *crc32.Table
+}
+
+// New creates a new hash.Hash32 computing the CRC-32 checksum
+// using the polynomial represented by the Table.
+// Modified by xiangli to take a prevcrc.
+func New(prev uint32, tab *crc32.Table) hash.Hash32 { return &digest{prev, tab} }
+
+func (d *digest) Size() int { return Size }
+
+func (d *digest) BlockSize() int { return 1 }
+
+func (d *digest) Reset() { d.crc = 0 }
+
+func (d *digest) Write(p []byte) (n int, err error) {
+	d.crc = crc32.Update(d.crc, d.tab, p)
+	return len(p), nil
+}
+
+func (d *digest) Sum32() uint32 { return d.crc }
+
+func (d *digest) Sum(in []byte) []byte {
+	s := d.Sum32()
+	return append(in, byte(s>>24), byte(s>>16), byte(s>>8), byte(s))
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/debugutil/doc.go b/vendor/github.com/coreos/etcd/pkg/debugutil/doc.go
new file mode 100644
index 0000000..74499eb
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/debugutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package debugutil includes utility functions for debugging.
+package debugutil
diff --git a/vendor/github.com/coreos/etcd/pkg/debugutil/pprof.go b/vendor/github.com/coreos/etcd/pkg/debugutil/pprof.go
new file mode 100644
index 0000000..8d5544a
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/debugutil/pprof.go
@@ -0,0 +1,47 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package debugutil
+
+import (
+	"net/http"
+	"net/http/pprof"
+	"runtime"
+)
+
+const HTTPPrefixPProf = "/debug/pprof"
+
+// PProfHandlers returns a map of pprof handlers keyed by the HTTP path.
+func PProfHandlers() map[string]http.Handler {
+	// set only when there's no existing setting
+	if runtime.SetMutexProfileFraction(-1) == 0 {
+		// 1 out of 5 mutex events are reported, on average
+		runtime.SetMutexProfileFraction(5)
+	}
+
+	m := make(map[string]http.Handler)
+
+	m[HTTPPrefixPProf+"/"] = http.HandlerFunc(pprof.Index)
+	m[HTTPPrefixPProf+"/profile"] = http.HandlerFunc(pprof.Profile)
+	m[HTTPPrefixPProf+"/symbol"] = http.HandlerFunc(pprof.Symbol)
+	m[HTTPPrefixPProf+"/cmdline"] = http.HandlerFunc(pprof.Cmdline)
+	m[HTTPPrefixPProf+"/trace "] = http.HandlerFunc(pprof.Trace)
+	m[HTTPPrefixPProf+"/heap"] = pprof.Handler("heap")
+	m[HTTPPrefixPProf+"/goroutine"] = pprof.Handler("goroutine")
+	m[HTTPPrefixPProf+"/threadcreate"] = pprof.Handler("threadcreate")
+	m[HTTPPrefixPProf+"/block"] = pprof.Handler("block")
+	m[HTTPPrefixPProf+"/mutex"] = pprof.Handler("mutex")
+
+	return m
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/dir_unix.go b/vendor/github.com/coreos/etcd/pkg/fileutil/dir_unix.go
new file mode 100644
index 0000000..4ce15dc
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/dir_unix.go
@@ -0,0 +1,27 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !windows
+
+package fileutil
+
+import "os"
+
+const (
+	// PrivateDirMode grants owner to make/remove files inside the directory.
+	PrivateDirMode = 0700
+)
+
+// OpenDir opens a directory for syncing.
+func OpenDir(path string) (*os.File, error) { return os.Open(path) }
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/dir_windows.go b/vendor/github.com/coreos/etcd/pkg/fileutil/dir_windows.go
new file mode 100644
index 0000000..a10a905
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/dir_windows.go
@@ -0,0 +1,51 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build windows
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+const (
+	// PrivateDirMode grants owner to make/remove files inside the directory.
+	PrivateDirMode = 0777
+)
+
+// OpenDir opens a directory in windows with write access for syncing.
+func OpenDir(path string) (*os.File, error) {
+	fd, err := openDir(path)
+	if err != nil {
+		return nil, err
+	}
+	return os.NewFile(uintptr(fd), path), nil
+}
+
+func openDir(path string) (fd syscall.Handle, err error) {
+	if len(path) == 0 {
+		return syscall.InvalidHandle, syscall.ERROR_FILE_NOT_FOUND
+	}
+	pathp, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return syscall.InvalidHandle, err
+	}
+	access := uint32(syscall.GENERIC_READ | syscall.GENERIC_WRITE)
+	sharemode := uint32(syscall.FILE_SHARE_READ | syscall.FILE_SHARE_WRITE)
+	createmode := uint32(syscall.OPEN_EXISTING)
+	fl := uint32(syscall.FILE_FLAG_BACKUP_SEMANTICS)
+	return syscall.CreateFile(pathp, access, sharemode, nil, createmode, fl, 0)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/fileutil.go b/vendor/github.com/coreos/etcd/pkg/fileutil/fileutil.go
new file mode 100644
index 0000000..3c73916
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/fileutil.go
@@ -0,0 +1,147 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package fileutil implements utility functions related to files and paths.
+package fileutil
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sort"
+
+	"github.com/coreos/pkg/capnslog"
+)
+
+const (
+	// PrivateFileMode grants owner to read/write a file.
+	PrivateFileMode = 0600
+)
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "pkg/fileutil")
+)
+
+// IsDirWriteable checks if dir is writable by writing and removing a file
+// to dir. It returns nil if dir is writable.
+func IsDirWriteable(dir string) error {
+	f := filepath.Join(dir, ".touch")
+	if err := ioutil.WriteFile(f, []byte(""), PrivateFileMode); err != nil {
+		return err
+	}
+	return os.Remove(f)
+}
+
+// ReadDir returns the filenames in the given directory in sorted order.
+func ReadDir(dirpath string) ([]string, error) {
+	dir, err := os.Open(dirpath)
+	if err != nil {
+		return nil, err
+	}
+	defer dir.Close()
+	names, err := dir.Readdirnames(-1)
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(names)
+	return names, nil
+}
+
+// TouchDirAll is similar to os.MkdirAll. It creates directories with 0700 permission if any directory
+// does not exists. TouchDirAll also ensures the given directory is writable.
+func TouchDirAll(dir string) error {
+	// If path is already a directory, MkdirAll does nothing and returns nil, so,
+	// first check if dir exist with an expected permission mode.
+	if Exist(dir) {
+		err := CheckDirPermission(dir, PrivateDirMode)
+		if err != nil {
+			plog.Warningf("check file permission: %v", err)
+		}
+	} else {
+		err := os.MkdirAll(dir, PrivateDirMode)
+		if err != nil {
+			// if mkdirAll("a/text") and "text" is not
+			// a directory, this will return syscall.ENOTDIR
+			return err
+		}
+	}
+
+	return IsDirWriteable(dir)
+}
+
+// CreateDirAll is similar to TouchDirAll but returns error
+// if the deepest directory was not empty.
+func CreateDirAll(dir string) error {
+	err := TouchDirAll(dir)
+	if err == nil {
+		var ns []string
+		ns, err = ReadDir(dir)
+		if err != nil {
+			return err
+		}
+		if len(ns) != 0 {
+			err = fmt.Errorf("expected %q to be empty, got %q", dir, ns)
+		}
+	}
+	return err
+}
+
+func Exist(name string) bool {
+	_, err := os.Stat(name)
+	return err == nil
+}
+
+// ZeroToEnd zeros a file starting from SEEK_CUR to its SEEK_END. May temporarily
+// shorten the length of the file.
+func ZeroToEnd(f *os.File) error {
+	// TODO: support FALLOC_FL_ZERO_RANGE
+	off, err := f.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return err
+	}
+	lenf, lerr := f.Seek(0, io.SeekEnd)
+	if lerr != nil {
+		return lerr
+	}
+	if err = f.Truncate(off); err != nil {
+		return err
+	}
+	// make sure blocks remain allocated
+	if err = Preallocate(f, lenf, true); err != nil {
+		return err
+	}
+	_, err = f.Seek(off, io.SeekStart)
+	return err
+}
+
+// CheckDirPermission checks permission on an existing dir.
+// Returns error if dir is empty or exist with a different permission than specified.
+func CheckDirPermission(dir string, perm os.FileMode) error {
+	if !Exist(dir) {
+		return fmt.Errorf("directory %q empty, cannot check permission.", dir)
+	}
+	//check the existing permission on the directory
+	dirInfo, err := os.Stat(dir)
+	if err != nil {
+		return err
+	}
+	dirMode := dirInfo.Mode().Perm()
+	if dirMode != perm {
+		err = fmt.Errorf("directory %q exist, but the permission is %q. The recommended permission is %q to prevent possible unprivileged access to the data.", dir, dirInfo.Mode(), os.FileMode(PrivateDirMode))
+		return err
+	}
+	return nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock.go
new file mode 100644
index 0000000..338627f
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock.go
@@ -0,0 +1,26 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fileutil
+
+import (
+	"errors"
+	"os"
+)
+
+var (
+	ErrLocked = errors.New("fileutil: file already locked")
+)
+
+type LockedFile struct{ *os.File }
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_flock.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_flock.go
new file mode 100644
index 0000000..542550b
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_flock.go
@@ -0,0 +1,49 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !windows,!plan9,!solaris
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func flockTryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
+		f.Close()
+		if err == syscall.EWOULDBLOCK {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func flockLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_linux.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_linux.go
new file mode 100644
index 0000000..939fea6
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_linux.go
@@ -0,0 +1,97 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+
+package fileutil
+
+import (
+	"io"
+	"os"
+	"syscall"
+)
+
+// This used to call syscall.Flock() but that call fails with EBADF on NFS.
+// An alternative is lockf() which works on NFS but that call lets a process lock
+// the same file twice. Instead, use Linux's non-standard open file descriptor
+// locks which will block if the process already holds the file lock.
+//
+// constants from /usr/include/bits/fcntl-linux.h
+const (
+	F_OFD_GETLK  = 37
+	F_OFD_SETLK  = 37
+	F_OFD_SETLKW = 38
+)
+
+var (
+	wrlck = syscall.Flock_t{
+		Type:   syscall.F_WRLCK,
+		Whence: int16(io.SeekStart),
+		Start:  0,
+		Len:    0,
+	}
+
+	linuxTryLockFile = flockTryLockFile
+	linuxLockFile    = flockLockFile
+)
+
+func init() {
+	// use open file descriptor locks if the system supports it
+	getlk := syscall.Flock_t{Type: syscall.F_RDLCK}
+	if err := syscall.FcntlFlock(0, F_OFD_GETLK, &getlk); err == nil {
+		linuxTryLockFile = ofdTryLockFile
+		linuxLockFile = ofdLockFile
+	}
+}
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return linuxTryLockFile(path, flag, perm)
+}
+
+func ofdTryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+
+	flock := wrlck
+	if err = syscall.FcntlFlock(f.Fd(), F_OFD_SETLK, &flock); err != nil {
+		f.Close()
+		if err == syscall.EWOULDBLOCK {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return linuxLockFile(path, flag, perm)
+}
+
+func ofdLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+
+	flock := wrlck
+	err = syscall.FcntlFlock(f.Fd(), F_OFD_SETLKW, &flock)
+
+	if err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_plan9.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_plan9.go
new file mode 100644
index 0000000..fee6a7c
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_plan9.go
@@ -0,0 +1,45 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+	"time"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	if err := os.Chmod(path, syscall.DMEXCL|PrivateFileMode); err != nil {
+		return nil, err
+	}
+	f, err := os.Open(path, flag, perm)
+	if err != nil {
+		return nil, ErrLocked
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	if err := os.Chmod(path, syscall.DMEXCL|PrivateFileMode); err != nil {
+		return nil, err
+	}
+	for {
+		f, err := os.OpenFile(path, flag, perm)
+		if err == nil {
+			return &LockedFile{f}, nil
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_solaris.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_solaris.go
new file mode 100644
index 0000000..352ca55
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_solaris.go
@@ -0,0 +1,62 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build solaris
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Pid = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	lock.Pid = 0
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := syscall.FcntlFlock(f.Fd(), syscall.F_SETLK, &lock); err != nil {
+		f.Close()
+		if err == syscall.EAGAIN {
+			err = ErrLocked
+		}
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	var lock syscall.Flock_t
+	lock.Start = 0
+	lock.Len = 0
+	lock.Pid = 0
+	lock.Type = syscall.F_WRLCK
+	lock.Whence = 0
+	f, err := os.OpenFile(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err = syscall.FcntlFlock(f.Fd(), syscall.F_SETLKW, &lock); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_unix.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_unix.go
new file mode 100644
index 0000000..ed01164
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_unix.go
@@ -0,0 +1,29 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !windows,!plan9,!solaris,!linux
+
+package fileutil
+
+import (
+	"os"
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return flockTryLockFile(path, flag, perm)
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	return flockLockFile(path, flag, perm)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/lock_windows.go b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_windows.go
new file mode 100644
index 0000000..b181723
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/lock_windows.go
@@ -0,0 +1,125 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build windows
+
+package fileutil
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+var (
+	modkernel32    = syscall.NewLazyDLL("kernel32.dll")
+	procLockFileEx = modkernel32.NewProc("LockFileEx")
+
+	errLocked = errors.New("The process cannot access the file because another process has locked a portion of the file.")
+)
+
+const (
+	// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
+	LOCKFILE_EXCLUSIVE_LOCK   = 2
+	LOCKFILE_FAIL_IMMEDIATELY = 1
+
+	// see https://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx
+	errLockViolation syscall.Errno = 0x21
+)
+
+func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := open(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := lockFile(syscall.Handle(f.Fd()), LOCKFILE_FAIL_IMMEDIATELY); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
+	f, err := open(path, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	if err := lockFile(syscall.Handle(f.Fd()), 0); err != nil {
+		f.Close()
+		return nil, err
+	}
+	return &LockedFile{f}, nil
+}
+
+func open(path string, flag int, perm os.FileMode) (*os.File, error) {
+	if path == "" {
+		return nil, fmt.Errorf("cannot open empty filename")
+	}
+	var access uint32
+	switch flag {
+	case syscall.O_RDONLY:
+		access = syscall.GENERIC_READ
+	case syscall.O_WRONLY:
+		access = syscall.GENERIC_WRITE
+	case syscall.O_RDWR:
+		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
+	case syscall.O_WRONLY | syscall.O_CREAT:
+		access = syscall.GENERIC_ALL
+	default:
+		panic(fmt.Errorf("flag %v is not supported", flag))
+	}
+	fd, err := syscall.CreateFile(&(syscall.StringToUTF16(path)[0]),
+		access,
+		syscall.FILE_SHARE_READ|syscall.FILE_SHARE_WRITE|syscall.FILE_SHARE_DELETE,
+		nil,
+		syscall.OPEN_ALWAYS,
+		syscall.FILE_ATTRIBUTE_NORMAL,
+		0)
+	if err != nil {
+		return nil, err
+	}
+	return os.NewFile(uintptr(fd), path), nil
+}
+
+func lockFile(fd syscall.Handle, flags uint32) error {
+	var flag uint32 = LOCKFILE_EXCLUSIVE_LOCK
+	flag |= flags
+	if fd == syscall.InvalidHandle {
+		return nil
+	}
+	err := lockFileEx(fd, flag, 1, 0, &syscall.Overlapped{})
+	if err == nil {
+		return nil
+	} else if err.Error() == errLocked.Error() {
+		return ErrLocked
+	} else if err != errLockViolation {
+		return err
+	}
+	return nil
+}
+
+func lockFileEx(h syscall.Handle, flags, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
+	var reserved uint32 = 0
+	r1, _, e1 := syscall.Syscall6(procLockFileEx.Addr(), 6, uintptr(h), uintptr(flags), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
+	if r1 == 0 {
+		if e1 != 0 {
+			err = error(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate.go b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate.go
new file mode 100644
index 0000000..c747b7c
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate.go
@@ -0,0 +1,54 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fileutil
+
+import (
+	"io"
+	"os"
+)
+
+// Preallocate tries to allocate the space for given
+// file. This operation is only supported on linux by a
+// few filesystems (btrfs, ext4, etc.).
+// If the operation is unsupported, no error will be returned.
+// Otherwise, the error encountered will be returned.
+func Preallocate(f *os.File, sizeInBytes int64, extendFile bool) error {
+	if sizeInBytes == 0 {
+		// fallocate will return EINVAL if length is 0; skip
+		return nil
+	}
+	if extendFile {
+		return preallocExtend(f, sizeInBytes)
+	}
+	return preallocFixed(f, sizeInBytes)
+}
+
+func preallocExtendTrunc(f *os.File, sizeInBytes int64) error {
+	curOff, err := f.Seek(0, io.SeekCurrent)
+	if err != nil {
+		return err
+	}
+	size, err := f.Seek(sizeInBytes, io.SeekEnd)
+	if err != nil {
+		return err
+	}
+	if _, err = f.Seek(curOff, io.SeekStart); err != nil {
+		return err
+	}
+	if sizeInBytes > size {
+		return nil
+	}
+	return f.Truncate(sizeInBytes)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_darwin.go b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_darwin.go
new file mode 100644
index 0000000..5a6dccf
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_darwin.go
@@ -0,0 +1,65 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build darwin
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+	"unsafe"
+)
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	if err := preallocFixed(f, sizeInBytes); err != nil {
+		return err
+	}
+	return preallocExtendTrunc(f, sizeInBytes)
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error {
+	// allocate all requested space or no space at all
+	// TODO: allocate contiguous space on disk with F_ALLOCATECONTIG flag
+	fstore := &syscall.Fstore_t{
+		Flags:   syscall.F_ALLOCATEALL,
+		Posmode: syscall.F_PEOFPOSMODE,
+		Length:  sizeInBytes}
+	p := unsafe.Pointer(fstore)
+	_, _, errno := syscall.Syscall(syscall.SYS_FCNTL, f.Fd(), uintptr(syscall.F_PREALLOCATE), uintptr(p))
+	if errno == 0 || errno == syscall.ENOTSUP {
+		return nil
+	}
+
+	// wrong argument to fallocate syscall
+	if errno == syscall.EINVAL {
+		// filesystem "st_blocks" are allocated in the units of
+		// "Allocation Block Size" (run "diskutil info /" command)
+		var stat syscall.Stat_t
+		syscall.Fstat(int(f.Fd()), &stat)
+
+		// syscall.Statfs_t.Bsize is "optimal transfer block size"
+		// and contains matching 4096 value when latest OS X kernel
+		// supports 4,096 KB filesystem block size
+		var statfs syscall.Statfs_t
+		syscall.Fstatfs(int(f.Fd()), &statfs)
+		blockSize := int64(statfs.Bsize)
+
+		if stat.Blocks*blockSize >= sizeInBytes {
+			// enough blocks are already allocated
+			return nil
+		}
+	}
+	return errno
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unix.go b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unix.go
new file mode 100644
index 0000000..50bd84f
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unix.go
@@ -0,0 +1,49 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	// use mode = 0 to change size
+	err := syscall.Fallocate(int(f.Fd()), 0, 0, sizeInBytes)
+	if err != nil {
+		errno, ok := err.(syscall.Errno)
+		// not supported; fallback
+		// fallocate EINTRs frequently in some environments; fallback
+		if ok && (errno == syscall.ENOTSUP || errno == syscall.EINTR) {
+			return preallocExtendTrunc(f, sizeInBytes)
+		}
+	}
+	return err
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error {
+	// use mode = 1 to keep size; see FALLOC_FL_KEEP_SIZE
+	err := syscall.Fallocate(int(f.Fd()), 1, 0, sizeInBytes)
+	if err != nil {
+		errno, ok := err.(syscall.Errno)
+		// treat not supported as nil error
+		if ok && errno == syscall.ENOTSUP {
+			return nil
+		}
+	}
+	return err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unsupported.go b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unsupported.go
new file mode 100644
index 0000000..162fbc5
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/preallocate_unsupported.go
@@ -0,0 +1,25 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !linux,!darwin
+
+package fileutil
+
+import "os"
+
+func preallocExtend(f *os.File, sizeInBytes int64) error {
+	return preallocExtendTrunc(f, sizeInBytes)
+}
+
+func preallocFixed(f *os.File, sizeInBytes int64) error { return nil }
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/purge.go b/vendor/github.com/coreos/etcd/pkg/fileutil/purge.go
new file mode 100644
index 0000000..c973680
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/purge.go
@@ -0,0 +1,88 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fileutil
+
+import (
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+)
+
+func PurgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error {
+	return purgeFile(dirname, suffix, max, interval, stop, nil, nil)
+}
+
+func PurgeFileWithDoneNotify(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) (<-chan struct{}, <-chan error) {
+	doneC := make(chan struct{})
+	errC := purgeFile(dirname, suffix, max, interval, stop, nil, doneC)
+	return doneC, errC
+}
+
+// purgeFile is the internal implementation for PurgeFile which can post purged files to purgec if non-nil.
+// if donec is non-nil, the function closes it to notify its exit.
+func purgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}, purgec chan<- string, donec chan<- struct{}) <-chan error {
+	errC := make(chan error, 1)
+	go func() {
+		if donec != nil {
+			defer close(donec)
+		}
+		for {
+			fnames, err := ReadDir(dirname)
+			if err != nil {
+				errC <- err
+				return
+			}
+			newfnames := make([]string, 0)
+			for _, fname := range fnames {
+				if strings.HasSuffix(fname, suffix) {
+					newfnames = append(newfnames, fname)
+				}
+			}
+			sort.Strings(newfnames)
+			fnames = newfnames
+			for len(newfnames) > int(max) {
+				f := filepath.Join(dirname, newfnames[0])
+				l, err := TryLockFile(f, os.O_WRONLY, PrivateFileMode)
+				if err != nil {
+					break
+				}
+				if err = os.Remove(f); err != nil {
+					errC <- err
+					return
+				}
+				if err = l.Close(); err != nil {
+					plog.Errorf("error unlocking %s when purging file (%v)", l.Name(), err)
+					errC <- err
+					return
+				}
+				plog.Infof("purged file %s successfully", f)
+				newfnames = newfnames[1:]
+			}
+			if purgec != nil {
+				for i := 0; i < len(fnames)-len(newfnames); i++ {
+					purgec <- fnames[i]
+				}
+			}
+			select {
+			case <-time.After(interval):
+			case <-stop:
+				return
+			}
+		}
+	}()
+	return errC
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/sync.go b/vendor/github.com/coreos/etcd/pkg/fileutil/sync.go
new file mode 100644
index 0000000..54dd41f
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/sync.go
@@ -0,0 +1,29 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !linux,!darwin
+
+package fileutil
+
+import "os"
+
+// Fsync is a wrapper around file.Sync(). Special handling is needed on darwin platform.
+func Fsync(f *os.File) error {
+	return f.Sync()
+}
+
+// Fdatasync is a wrapper around file.Sync(). Special handling is needed on linux platform.
+func Fdatasync(f *os.File) error {
+	return f.Sync()
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/sync_darwin.go b/vendor/github.com/coreos/etcd/pkg/fileutil/sync_darwin.go
new file mode 100644
index 0000000..c2f39bf
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/sync_darwin.go
@@ -0,0 +1,40 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build darwin
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// Fsync on HFS/OSX flushes the data on to the physical drive but the drive
+// may not write it to the persistent media for quite sometime and it may be
+// written in out-of-order sequence. Using F_FULLFSYNC ensures that the
+// physical drive's buffer will also get flushed to the media.
+func Fsync(f *os.File) error {
+	_, _, errno := syscall.Syscall(syscall.SYS_FCNTL, f.Fd(), uintptr(syscall.F_FULLFSYNC), uintptr(0))
+	if errno == 0 {
+		return nil
+	}
+	return errno
+}
+
+// Fdatasync on darwin platform invokes fcntl(F_FULLFSYNC) for actual persistence
+// on physical drive media.
+func Fdatasync(f *os.File) error {
+	return Fsync(f)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/fileutil/sync_linux.go b/vendor/github.com/coreos/etcd/pkg/fileutil/sync_linux.go
new file mode 100644
index 0000000..1bbced9
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/fileutil/sync_linux.go
@@ -0,0 +1,34 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+
+package fileutil
+
+import (
+	"os"
+	"syscall"
+)
+
+// Fsync is a wrapper around file.Sync(). Special handling is needed on darwin platform.
+func Fsync(f *os.File) error {
+	return f.Sync()
+}
+
+// Fdatasync is similar to fsync(), but does not flush modified metadata
+// unless that metadata is needed in order to allow a subsequent data retrieval
+// to be correctly handled.
+func Fdatasync(f *os.File) error {
+	return syscall.Fdatasync(int(f.Fd()))
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/httputil/httputil.go b/vendor/github.com/coreos/etcd/pkg/httputil/httputil.go
new file mode 100644
index 0000000..09f44e7
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/httputil/httputil.go
@@ -0,0 +1,22 @@
+// 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.
+
+// borrowed from golang/net/context/ctxhttp/cancelreq.go
+
+// Package httputil provides HTTP utility functions.
+package httputil
+
+import (
+	"io"
+	"io/ioutil"
+	"net/http"
+)
+
+// GracefulClose drains http.Response.Body until it hits EOF
+// and closes it. This prevents TCP/TLS connections from closing,
+// therefore available for reuse.
+func GracefulClose(resp *http.Response) {
+	io.Copy(ioutil.Discard, resp.Body)
+	resp.Body.Close()
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/idutil/id.go b/vendor/github.com/coreos/etcd/pkg/idutil/id.go
new file mode 100644
index 0000000..2da2106
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/idutil/id.go
@@ -0,0 +1,78 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package idutil implements utility functions for generating unique,
+// randomized ids.
+package idutil
+
+import (
+	"math"
+	"sync"
+	"time"
+)
+
+const (
+	tsLen     = 5 * 8
+	cntLen    = 8
+	suffixLen = tsLen + cntLen
+)
+
+// Generator generates unique identifiers based on counters, timestamps, and
+// a node member ID.
+//
+// The initial id is in this format:
+// High order 2 bytes are from memberID, next 5 bytes are from timestamp,
+// and low order one byte is a counter.
+// | prefix   | suffix              |
+// | 2 bytes  | 5 bytes   | 1 byte  |
+// | memberID | timestamp | cnt     |
+//
+// The timestamp 5 bytes is different when the machine is restart
+// after 1 ms and before 35 years.
+//
+// It increases suffix to generate the next id.
+// The count field may overflow to timestamp field, which is intentional.
+// It helps to extend the event window to 2^56. This doesn't break that
+// id generated after restart is unique because etcd throughput is <<
+// 256req/ms(250k reqs/second).
+type Generator struct {
+	mu sync.Mutex
+	// high order 2 bytes
+	prefix uint64
+	// low order 6 bytes
+	suffix uint64
+}
+
+func NewGenerator(memberID uint16, now time.Time) *Generator {
+	prefix := uint64(memberID) << suffixLen
+	unixMilli := uint64(now.UnixNano()) / uint64(time.Millisecond/time.Nanosecond)
+	suffix := lowbit(unixMilli, tsLen) << cntLen
+	return &Generator{
+		prefix: prefix,
+		suffix: suffix,
+	}
+}
+
+// Next generates a id that is unique.
+func (g *Generator) Next() uint64 {
+	g.mu.Lock()
+	defer g.mu.Unlock()
+	g.suffix++
+	id := g.prefix | lowbit(g.suffix, suffixLen)
+	return id
+}
+
+func lowbit(x uint64, n uint) uint64 {
+	return x & (math.MaxUint64 >> (64 - n))
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/ioutil/pagewriter.go b/vendor/github.com/coreos/etcd/pkg/ioutil/pagewriter.go
new file mode 100644
index 0000000..cf9a8dc
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/ioutil/pagewriter.go
@@ -0,0 +1,117 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ioutil
+
+import (
+	"io"
+)
+
+var defaultBufferBytes = 128 * 1024
+
+// PageWriter implements the io.Writer interface so that writes will
+// either be in page chunks or from flushing.
+type PageWriter struct {
+	w io.Writer
+	// pageOffset tracks the page offset of the base of the buffer
+	pageOffset int
+	// pageBytes is the number of bytes per page
+	pageBytes int
+	// bufferedBytes counts the number of bytes pending for write in the buffer
+	bufferedBytes int
+	// buf holds the write buffer
+	buf []byte
+	// bufWatermarkBytes is the number of bytes the buffer can hold before it needs
+	// to be flushed. It is less than len(buf) so there is space for slack writes
+	// to bring the writer to page alignment.
+	bufWatermarkBytes int
+}
+
+// NewPageWriter creates a new PageWriter. pageBytes is the number of bytes
+// to write per page. pageOffset is the starting offset of io.Writer.
+func NewPageWriter(w io.Writer, pageBytes, pageOffset int) *PageWriter {
+	return &PageWriter{
+		w:                 w,
+		pageOffset:        pageOffset,
+		pageBytes:         pageBytes,
+		buf:               make([]byte, defaultBufferBytes+pageBytes),
+		bufWatermarkBytes: defaultBufferBytes,
+	}
+}
+
+func (pw *PageWriter) Write(p []byte) (n int, err error) {
+	if len(p)+pw.bufferedBytes <= pw.bufWatermarkBytes {
+		// no overflow
+		copy(pw.buf[pw.bufferedBytes:], p)
+		pw.bufferedBytes += len(p)
+		return len(p), nil
+	}
+	// complete the slack page in the buffer if unaligned
+	slack := pw.pageBytes - ((pw.pageOffset + pw.bufferedBytes) % pw.pageBytes)
+	if slack != pw.pageBytes {
+		partial := slack > len(p)
+		if partial {
+			// not enough data to complete the slack page
+			slack = len(p)
+		}
+		// special case: writing to slack page in buffer
+		copy(pw.buf[pw.bufferedBytes:], p[:slack])
+		pw.bufferedBytes += slack
+		n = slack
+		p = p[slack:]
+		if partial {
+			// avoid forcing an unaligned flush
+			return n, nil
+		}
+	}
+	// buffer contents are now page-aligned; clear out
+	if err = pw.Flush(); err != nil {
+		return n, err
+	}
+	// directly write all complete pages without copying
+	if len(p) > pw.pageBytes {
+		pages := len(p) / pw.pageBytes
+		c, werr := pw.w.Write(p[:pages*pw.pageBytes])
+		n += c
+		if werr != nil {
+			return n, werr
+		}
+		p = p[pages*pw.pageBytes:]
+	}
+	// write remaining tail to buffer
+	c, werr := pw.Write(p)
+	n += c
+	return n, werr
+}
+
+// Flush flushes buffered data.
+func (pw *PageWriter) Flush() error {
+	_, err := pw.flush()
+	return err
+}
+
+// FlushN flushes buffered data and returns the number of written bytes.
+func (pw *PageWriter) FlushN() (int, error) {
+	return pw.flush()
+}
+
+func (pw *PageWriter) flush() (int, error) {
+	if pw.bufferedBytes == 0 {
+		return 0, nil
+	}
+	n, err := pw.w.Write(pw.buf[:pw.bufferedBytes])
+	pw.pageOffset = (pw.pageOffset + pw.bufferedBytes) % pw.pageBytes
+	pw.bufferedBytes = 0
+	return n, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/ioutil/readcloser.go b/vendor/github.com/coreos/etcd/pkg/ioutil/readcloser.go
new file mode 100644
index 0000000..d3efcfe
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/ioutil/readcloser.go
@@ -0,0 +1,66 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ioutil
+
+import (
+	"fmt"
+	"io"
+)
+
+// ReaderAndCloser implements io.ReadCloser interface by combining
+// reader and closer together.
+type ReaderAndCloser struct {
+	io.Reader
+	io.Closer
+}
+
+var (
+	ErrShortRead = fmt.Errorf("ioutil: short read")
+	ErrExpectEOF = fmt.Errorf("ioutil: expect EOF")
+)
+
+// NewExactReadCloser returns a ReadCloser that returns errors if the underlying
+// reader does not read back exactly the requested number of bytes.
+func NewExactReadCloser(rc io.ReadCloser, totalBytes int64) io.ReadCloser {
+	return &exactReadCloser{rc: rc, totalBytes: totalBytes}
+}
+
+type exactReadCloser struct {
+	rc         io.ReadCloser
+	br         int64
+	totalBytes int64
+}
+
+func (e *exactReadCloser) Read(p []byte) (int, error) {
+	n, err := e.rc.Read(p)
+	e.br += int64(n)
+	if e.br > e.totalBytes {
+		return 0, ErrExpectEOF
+	}
+	if e.br < e.totalBytes && n == 0 {
+		return 0, ErrShortRead
+	}
+	return n, err
+}
+
+func (e *exactReadCloser) Close() error {
+	if err := e.rc.Close(); err != nil {
+		return err
+	}
+	if e.br < e.totalBytes {
+		return ErrShortRead
+	}
+	return nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/ioutil/reader.go b/vendor/github.com/coreos/etcd/pkg/ioutil/reader.go
new file mode 100644
index 0000000..0703ed4
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/ioutil/reader.go
@@ -0,0 +1,40 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package ioutil implements I/O utility functions.
+package ioutil
+
+import "io"
+
+// NewLimitedBufferReader returns a reader that reads from the given reader
+// but limits the amount of data returned to at most n bytes.
+func NewLimitedBufferReader(r io.Reader, n int) io.Reader {
+	return &limitedBufferReader{
+		r: r,
+		n: n,
+	}
+}
+
+type limitedBufferReader struct {
+	r io.Reader
+	n int
+}
+
+func (r *limitedBufferReader) Read(p []byte) (n int, err error) {
+	np := p
+	if len(np) > r.n {
+		np = np[:r.n]
+	}
+	return r.r.Read(np)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/ioutil/util.go b/vendor/github.com/coreos/etcd/pkg/ioutil/util.go
new file mode 100644
index 0000000..192ad88
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/ioutil/util.go
@@ -0,0 +1,43 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ioutil
+
+import (
+	"io"
+	"os"
+
+	"github.com/coreos/etcd/pkg/fileutil"
+)
+
+// WriteAndSyncFile behaves just like ioutil.WriteFile in the standard library,
+// but calls Sync before closing the file. WriteAndSyncFile guarantees the data
+// is synced if there is no error returned.
+func WriteAndSyncFile(filename string, data []byte, perm os.FileMode) error {
+	f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+	if err != nil {
+		return err
+	}
+	n, err := f.Write(data)
+	if err == nil && n < len(data) {
+		err = io.ErrShortWrite
+	}
+	if err == nil {
+		err = fileutil.Fsync(f)
+	}
+	if err1 := f.Close(); err == nil {
+		err = err1
+	}
+	return err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/discard_logger.go b/vendor/github.com/coreos/etcd/pkg/logutil/discard_logger.go
new file mode 100644
index 0000000..81b0a9d
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/discard_logger.go
@@ -0,0 +1,46 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"log"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+// assert that "discardLogger" satisfy "Logger" interface
+var _ Logger = &discardLogger{}
+
+// NewDiscardLogger returns a new Logger that discards everything except "fatal".
+func NewDiscardLogger() Logger { return &discardLogger{} }
+
+type discardLogger struct{}
+
+func (l *discardLogger) Info(args ...interface{})                    {}
+func (l *discardLogger) Infoln(args ...interface{})                  {}
+func (l *discardLogger) Infof(format string, args ...interface{})    {}
+func (l *discardLogger) Warning(args ...interface{})                 {}
+func (l *discardLogger) Warningln(args ...interface{})               {}
+func (l *discardLogger) Warningf(format string, args ...interface{}) {}
+func (l *discardLogger) Error(args ...interface{})                   {}
+func (l *discardLogger) Errorln(args ...interface{})                 {}
+func (l *discardLogger) Errorf(format string, args ...interface{})   {}
+func (l *discardLogger) Fatal(args ...interface{})                   { log.Fatal(args...) }
+func (l *discardLogger) Fatalln(args ...interface{})                 { log.Fatalln(args...) }
+func (l *discardLogger) Fatalf(format string, args ...interface{})   { log.Fatalf(format, args...) }
+func (l *discardLogger) V(lvl int) bool {
+	return false
+}
+func (l *discardLogger) Lvl(lvl int) grpclog.LoggerV2 { return l }
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/doc.go b/vendor/github.com/coreos/etcd/pkg/logutil/doc.go
new file mode 100644
index 0000000..e919f24
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package logutil includes utilities to facilitate logging.
+package logutil
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/log_level.go b/vendor/github.com/coreos/etcd/pkg/logutil/log_level.go
new file mode 100644
index 0000000..d57e173
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/log_level.go
@@ -0,0 +1,70 @@
+// Copyright 2019 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"fmt"
+
+	"github.com/coreos/pkg/capnslog"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+var DefaultLogLevel = "info"
+
+// ConvertToZapLevel converts log level string to zapcore.Level.
+func ConvertToZapLevel(lvl string) zapcore.Level {
+	switch lvl {
+	case "debug":
+		return zap.DebugLevel
+	case "info":
+		return zap.InfoLevel
+	case "warn":
+		return zap.WarnLevel
+	case "error":
+		return zap.ErrorLevel
+	case "dpanic":
+		return zap.DPanicLevel
+	case "panic":
+		return zap.PanicLevel
+	case "fatal":
+		return zap.FatalLevel
+	default:
+		panic(fmt.Sprintf("unknown level %q", lvl))
+	}
+}
+
+// ConvertToCapnslogLogLevel convert log level string to capnslog.LogLevel.
+// TODO: deprecate this in 3.5
+func ConvertToCapnslogLogLevel(lvl string) capnslog.LogLevel {
+	switch lvl {
+	case "debug":
+		return capnslog.DEBUG
+	case "info":
+		return capnslog.INFO
+	case "warn":
+		return capnslog.WARNING
+	case "error":
+		return capnslog.ERROR
+	case "dpanic":
+		return capnslog.CRITICAL
+	case "panic":
+		return capnslog.CRITICAL
+	case "fatal":
+		return capnslog.CRITICAL
+	default:
+		panic(fmt.Sprintf("unknown level %q", lvl))
+	}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/logger.go b/vendor/github.com/coreos/etcd/pkg/logutil/logger.go
new file mode 100644
index 0000000..e7da80e
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/logger.go
@@ -0,0 +1,64 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import "google.golang.org/grpc/grpclog"
+
+// Logger defines logging interface.
+// TODO: deprecate in v3.5.
+type Logger interface {
+	grpclog.LoggerV2
+
+	// Lvl returns logger if logger's verbosity level >= "lvl".
+	// Otherwise, logger that discards everything.
+	Lvl(lvl int) grpclog.LoggerV2
+}
+
+// assert that "defaultLogger" satisfy "Logger" interface
+var _ Logger = &defaultLogger{}
+
+// NewLogger wraps "grpclog.LoggerV2" that implements "Logger" interface.
+//
+// For example:
+//
+//  var defaultLogger Logger
+//  g := grpclog.NewLoggerV2WithVerbosity(os.Stderr, os.Stderr, os.Stderr, 4)
+//  defaultLogger = NewLogger(g)
+//
+func NewLogger(g grpclog.LoggerV2) Logger { return &defaultLogger{g: g} }
+
+type defaultLogger struct {
+	g grpclog.LoggerV2
+}
+
+func (l *defaultLogger) Info(args ...interface{})                    { l.g.Info(args...) }
+func (l *defaultLogger) Infoln(args ...interface{})                  { l.g.Info(args...) }
+func (l *defaultLogger) Infof(format string, args ...interface{})    { l.g.Infof(format, args...) }
+func (l *defaultLogger) Warning(args ...interface{})                 { l.g.Warning(args...) }
+func (l *defaultLogger) Warningln(args ...interface{})               { l.g.Warning(args...) }
+func (l *defaultLogger) Warningf(format string, args ...interface{}) { l.g.Warningf(format, args...) }
+func (l *defaultLogger) Error(args ...interface{})                   { l.g.Error(args...) }
+func (l *defaultLogger) Errorln(args ...interface{})                 { l.g.Error(args...) }
+func (l *defaultLogger) Errorf(format string, args ...interface{})   { l.g.Errorf(format, args...) }
+func (l *defaultLogger) Fatal(args ...interface{})                   { l.g.Fatal(args...) }
+func (l *defaultLogger) Fatalln(args ...interface{})                 { l.g.Fatal(args...) }
+func (l *defaultLogger) Fatalf(format string, args ...interface{})   { l.g.Fatalf(format, args...) }
+func (l *defaultLogger) V(lvl int) bool                              { return l.g.V(lvl) }
+func (l *defaultLogger) Lvl(lvl int) grpclog.LoggerV2 {
+	if l.g.V(lvl) {
+		return l
+	}
+	return &discardLogger{}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go b/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go
new file mode 100644
index 0000000..866b6f7
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/merge_logger.go
@@ -0,0 +1,194 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/coreos/pkg/capnslog"
+)
+
+var (
+	defaultMergePeriod     = time.Second
+	defaultTimeOutputScale = 10 * time.Millisecond
+
+	outputInterval = time.Second
+)
+
+// line represents a log line that can be printed out
+// through capnslog.PackageLogger.
+type line struct {
+	level capnslog.LogLevel
+	str   string
+}
+
+func (l line) append(s string) line {
+	return line{
+		level: l.level,
+		str:   l.str + " " + s,
+	}
+}
+
+// status represents the merge status of a line.
+type status struct {
+	period time.Duration
+
+	start time.Time // start time of latest merge period
+	count int       // number of merged lines from starting
+}
+
+func (s *status) isInMergePeriod(now time.Time) bool {
+	return s.period == 0 || s.start.Add(s.period).After(now)
+}
+
+func (s *status) isEmpty() bool { return s.count == 0 }
+
+func (s *status) summary(now time.Time) string {
+	ts := s.start.Round(defaultTimeOutputScale)
+	took := now.Round(defaultTimeOutputScale).Sub(ts)
+	return fmt.Sprintf("[merged %d repeated lines in %s]", s.count, took)
+}
+
+func (s *status) reset(now time.Time) {
+	s.start = now
+	s.count = 0
+}
+
+// MergeLogger supports merge logging, which merges repeated log lines
+// and prints summary log lines instead.
+//
+// For merge logging, MergeLogger prints out the line when the line appears
+// at the first time. MergeLogger holds the same log line printed within
+// defaultMergePeriod, and prints out summary log line at the end of defaultMergePeriod.
+// It stops merging when the line doesn't appear within the
+// defaultMergePeriod.
+type MergeLogger struct {
+	*capnslog.PackageLogger
+
+	mu      sync.Mutex // protect statusm
+	statusm map[line]*status
+}
+
+func NewMergeLogger(logger *capnslog.PackageLogger) *MergeLogger {
+	l := &MergeLogger{
+		PackageLogger: logger,
+		statusm:       make(map[line]*status),
+	}
+	go l.outputLoop()
+	return l
+}
+
+func (l *MergeLogger) MergeInfo(entries ...interface{}) {
+	l.merge(line{
+		level: capnslog.INFO,
+		str:   fmt.Sprint(entries...),
+	})
+}
+
+func (l *MergeLogger) MergeInfof(format string, args ...interface{}) {
+	l.merge(line{
+		level: capnslog.INFO,
+		str:   fmt.Sprintf(format, args...),
+	})
+}
+
+func (l *MergeLogger) MergeNotice(entries ...interface{}) {
+	l.merge(line{
+		level: capnslog.NOTICE,
+		str:   fmt.Sprint(entries...),
+	})
+}
+
+func (l *MergeLogger) MergeNoticef(format string, args ...interface{}) {
+	l.merge(line{
+		level: capnslog.NOTICE,
+		str:   fmt.Sprintf(format, args...),
+	})
+}
+
+func (l *MergeLogger) MergeWarning(entries ...interface{}) {
+	l.merge(line{
+		level: capnslog.WARNING,
+		str:   fmt.Sprint(entries...),
+	})
+}
+
+func (l *MergeLogger) MergeWarningf(format string, args ...interface{}) {
+	l.merge(line{
+		level: capnslog.WARNING,
+		str:   fmt.Sprintf(format, args...),
+	})
+}
+
+func (l *MergeLogger) MergeError(entries ...interface{}) {
+	l.merge(line{
+		level: capnslog.ERROR,
+		str:   fmt.Sprint(entries...),
+	})
+}
+
+func (l *MergeLogger) MergeErrorf(format string, args ...interface{}) {
+	l.merge(line{
+		level: capnslog.ERROR,
+		str:   fmt.Sprintf(format, args...),
+	})
+}
+
+func (l *MergeLogger) merge(ln line) {
+	l.mu.Lock()
+
+	// increase count if the logger is merging the line
+	if status, ok := l.statusm[ln]; ok {
+		status.count++
+		l.mu.Unlock()
+		return
+	}
+
+	// initialize status of the line
+	l.statusm[ln] = &status{
+		period: defaultMergePeriod,
+		start:  time.Now(),
+	}
+	// release the lock before IO operation
+	l.mu.Unlock()
+	// print out the line at its first time
+	l.PackageLogger.Logf(ln.level, ln.str)
+}
+
+func (l *MergeLogger) outputLoop() {
+	for now := range time.Tick(outputInterval) {
+		var outputs []line
+
+		l.mu.Lock()
+		for ln, status := range l.statusm {
+			if status.isInMergePeriod(now) {
+				continue
+			}
+			if status.isEmpty() {
+				delete(l.statusm, ln)
+				continue
+			}
+			outputs = append(outputs, ln.append(status.summary(now)))
+			status.reset(now)
+		}
+		l.mu.Unlock()
+
+		for _, o := range outputs {
+			l.PackageLogger.Logf(o.level, o.str)
+		}
+	}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/package_logger.go b/vendor/github.com/coreos/etcd/pkg/logutil/package_logger.go
new file mode 100644
index 0000000..378bee0
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/package_logger.go
@@ -0,0 +1,60 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"github.com/coreos/pkg/capnslog"
+	"google.golang.org/grpc/grpclog"
+)
+
+// assert that "packageLogger" satisfy "Logger" interface
+var _ Logger = &packageLogger{}
+
+// NewPackageLogger wraps "*capnslog.PackageLogger" that implements "Logger" interface.
+//
+// For example:
+//
+//  var defaultLogger Logger
+//  defaultLogger = NewPackageLogger("github.com/coreos/etcd", "snapshot")
+//
+func NewPackageLogger(repo, pkg string) Logger {
+	return &packageLogger{p: capnslog.NewPackageLogger(repo, pkg)}
+}
+
+type packageLogger struct {
+	p *capnslog.PackageLogger
+}
+
+func (l *packageLogger) Info(args ...interface{})                    { l.p.Info(args...) }
+func (l *packageLogger) Infoln(args ...interface{})                  { l.p.Info(args...) }
+func (l *packageLogger) Infof(format string, args ...interface{})    { l.p.Infof(format, args...) }
+func (l *packageLogger) Warning(args ...interface{})                 { l.p.Warning(args...) }
+func (l *packageLogger) Warningln(args ...interface{})               { l.p.Warning(args...) }
+func (l *packageLogger) Warningf(format string, args ...interface{}) { l.p.Warningf(format, args...) }
+func (l *packageLogger) Error(args ...interface{})                   { l.p.Error(args...) }
+func (l *packageLogger) Errorln(args ...interface{})                 { l.p.Error(args...) }
+func (l *packageLogger) Errorf(format string, args ...interface{})   { l.p.Errorf(format, args...) }
+func (l *packageLogger) Fatal(args ...interface{})                   { l.p.Fatal(args...) }
+func (l *packageLogger) Fatalln(args ...interface{})                 { l.p.Fatal(args...) }
+func (l *packageLogger) Fatalf(format string, args ...interface{})   { l.p.Fatalf(format, args...) }
+func (l *packageLogger) V(lvl int) bool {
+	return l.p.LevelAt(capnslog.LogLevel(lvl))
+}
+func (l *packageLogger) Lvl(lvl int) grpclog.LoggerV2 {
+	if l.p.LevelAt(capnslog.LogLevel(lvl)) {
+		return l
+	}
+	return &discardLogger{}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/zap.go b/vendor/github.com/coreos/etcd/pkg/logutil/zap.go
new file mode 100644
index 0000000..2f69223
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/zap.go
@@ -0,0 +1,97 @@
+// Copyright 2019 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"sort"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+// DefaultZapLoggerConfig defines default zap logger configuration.
+var DefaultZapLoggerConfig = zap.Config{
+	Level: zap.NewAtomicLevelAt(ConvertToZapLevel(DefaultLogLevel)),
+
+	Development: false,
+	Sampling: &zap.SamplingConfig{
+		Initial:    100,
+		Thereafter: 100,
+	},
+
+	Encoding: "json",
+
+	// copied from "zap.NewProductionEncoderConfig" with some updates
+	EncoderConfig: zapcore.EncoderConfig{
+		TimeKey:        "ts",
+		LevelKey:       "level",
+		NameKey:        "logger",
+		CallerKey:      "caller",
+		MessageKey:     "msg",
+		StacktraceKey:  "stacktrace",
+		LineEnding:     zapcore.DefaultLineEnding,
+		EncodeLevel:    zapcore.LowercaseLevelEncoder,
+		EncodeTime:     zapcore.ISO8601TimeEncoder,
+		EncodeDuration: zapcore.StringDurationEncoder,
+		EncodeCaller:   zapcore.ShortCallerEncoder,
+	},
+
+	// Use "/dev/null" to discard all
+	OutputPaths:      []string{"stderr"},
+	ErrorOutputPaths: []string{"stderr"},
+}
+
+// AddOutputPaths adds output paths to the existing output paths, resolving conflicts.
+func AddOutputPaths(cfg zap.Config, outputPaths, errorOutputPaths []string) zap.Config {
+	outputs := make(map[string]struct{})
+	for _, v := range cfg.OutputPaths {
+		outputs[v] = struct{}{}
+	}
+	for _, v := range outputPaths {
+		outputs[v] = struct{}{}
+	}
+	outputSlice := make([]string, 0)
+	if _, ok := outputs["/dev/null"]; ok {
+		// "/dev/null" to discard all
+		outputSlice = []string{"/dev/null"}
+	} else {
+		for k := range outputs {
+			outputSlice = append(outputSlice, k)
+		}
+	}
+	cfg.OutputPaths = outputSlice
+	sort.Strings(cfg.OutputPaths)
+
+	errOutputs := make(map[string]struct{})
+	for _, v := range cfg.ErrorOutputPaths {
+		errOutputs[v] = struct{}{}
+	}
+	for _, v := range errorOutputPaths {
+		errOutputs[v] = struct{}{}
+	}
+	errOutputSlice := make([]string, 0)
+	if _, ok := errOutputs["/dev/null"]; ok {
+		// "/dev/null" to discard all
+		errOutputSlice = []string{"/dev/null"}
+	} else {
+		for k := range errOutputs {
+			errOutputSlice = append(errOutputSlice, k)
+		}
+	}
+	cfg.ErrorOutputPaths = errOutputSlice
+	sort.Strings(cfg.ErrorOutputPaths)
+
+	return cfg
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/zap_grpc.go b/vendor/github.com/coreos/etcd/pkg/logutil/zap_grpc.go
new file mode 100644
index 0000000..3f48d81
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/zap_grpc.go
@@ -0,0 +1,111 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+	"google.golang.org/grpc/grpclog"
+)
+
+// NewGRPCLoggerV2 converts "*zap.Logger" to "grpclog.LoggerV2".
+// It discards all INFO level logging in gRPC, if debug level
+// is not enabled in "*zap.Logger".
+func NewGRPCLoggerV2(lcfg zap.Config) (grpclog.LoggerV2, error) {
+	lg, err := lcfg.Build(zap.AddCallerSkip(1)) // to annotate caller outside of "logutil"
+	if err != nil {
+		return nil, err
+	}
+	return &zapGRPCLogger{lg: lg, sugar: lg.Sugar()}, nil
+}
+
+// NewGRPCLoggerV2FromZapCore creates "grpclog.LoggerV2" from "zap.Core"
+// and "zapcore.WriteSyncer". It discards all INFO level logging in gRPC,
+// if debug level is not enabled in "*zap.Logger".
+func NewGRPCLoggerV2FromZapCore(cr zapcore.Core, syncer zapcore.WriteSyncer) grpclog.LoggerV2 {
+	// "AddCallerSkip" to annotate caller outside of "logutil"
+	lg := zap.New(cr, zap.AddCaller(), zap.AddCallerSkip(1), zap.ErrorOutput(syncer))
+	return &zapGRPCLogger{lg: lg, sugar: lg.Sugar()}
+}
+
+type zapGRPCLogger struct {
+	lg    *zap.Logger
+	sugar *zap.SugaredLogger
+}
+
+func (zl *zapGRPCLogger) Info(args ...interface{}) {
+	if !zl.lg.Core().Enabled(zapcore.DebugLevel) {
+		return
+	}
+	zl.sugar.Info(args...)
+}
+
+func (zl *zapGRPCLogger) Infoln(args ...interface{}) {
+	if !zl.lg.Core().Enabled(zapcore.DebugLevel) {
+		return
+	}
+	zl.sugar.Info(args...)
+}
+
+func (zl *zapGRPCLogger) Infof(format string, args ...interface{}) {
+	if !zl.lg.Core().Enabled(zapcore.DebugLevel) {
+		return
+	}
+	zl.sugar.Infof(format, args...)
+}
+
+func (zl *zapGRPCLogger) Warning(args ...interface{}) {
+	zl.sugar.Warn(args...)
+}
+
+func (zl *zapGRPCLogger) Warningln(args ...interface{}) {
+	zl.sugar.Warn(args...)
+}
+
+func (zl *zapGRPCLogger) Warningf(format string, args ...interface{}) {
+	zl.sugar.Warnf(format, args...)
+}
+
+func (zl *zapGRPCLogger) Error(args ...interface{}) {
+	zl.sugar.Error(args...)
+}
+
+func (zl *zapGRPCLogger) Errorln(args ...interface{}) {
+	zl.sugar.Error(args...)
+}
+
+func (zl *zapGRPCLogger) Errorf(format string, args ...interface{}) {
+	zl.sugar.Errorf(format, args...)
+}
+
+func (zl *zapGRPCLogger) Fatal(args ...interface{}) {
+	zl.sugar.Fatal(args...)
+}
+
+func (zl *zapGRPCLogger) Fatalln(args ...interface{}) {
+	zl.sugar.Fatal(args...)
+}
+
+func (zl *zapGRPCLogger) Fatalf(format string, args ...interface{}) {
+	zl.sugar.Fatalf(format, args...)
+}
+
+func (zl *zapGRPCLogger) V(l int) bool {
+	// infoLog == 0
+	if l <= 0 { // debug level, then we ignore info level in gRPC
+		return !zl.lg.Core().Enabled(zapcore.DebugLevel)
+	}
+	return true
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/zap_journal.go b/vendor/github.com/coreos/etcd/pkg/logutil/zap_journal.go
new file mode 100644
index 0000000..b1788bc
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/zap_journal.go
@@ -0,0 +1,92 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !windows
+
+package logutil
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/coreos/etcd/pkg/systemd"
+
+	"github.com/coreos/go-systemd/journal"
+	"go.uber.org/zap/zapcore"
+)
+
+// NewJournalWriter wraps "io.Writer" to redirect log output
+// to the local systemd journal. If journald send fails, it fails
+// back to writing to the original writer.
+// The decode overhead is only <30µs per write.
+// Reference: https://github.com/coreos/pkg/blob/master/capnslog/journald_formatter.go
+func NewJournalWriter(wr io.Writer) (io.Writer, error) {
+	return &journalWriter{Writer: wr}, systemd.DialJournal()
+}
+
+type journalWriter struct {
+	io.Writer
+}
+
+// WARN: assume that etcd uses default field names in zap encoder config
+// make sure to keep this up-to-date!
+type logLine struct {
+	Level  string `json:"level"`
+	Caller string `json:"caller"`
+}
+
+func (w *journalWriter) Write(p []byte) (int, error) {
+	line := &logLine{}
+	if err := json.NewDecoder(bytes.NewReader(p)).Decode(line); err != nil {
+		return 0, err
+	}
+
+	var pri journal.Priority
+	switch line.Level {
+	case zapcore.DebugLevel.String():
+		pri = journal.PriDebug
+	case zapcore.InfoLevel.String():
+		pri = journal.PriInfo
+
+	case zapcore.WarnLevel.String():
+		pri = journal.PriWarning
+	case zapcore.ErrorLevel.String():
+		pri = journal.PriErr
+
+	case zapcore.DPanicLevel.String():
+		pri = journal.PriCrit
+	case zapcore.PanicLevel.String():
+		pri = journal.PriCrit
+	case zapcore.FatalLevel.String():
+		pri = journal.PriCrit
+
+	default:
+		panic(fmt.Errorf("unknown log level: %q", line.Level))
+	}
+
+	err := journal.Send(string(p), pri, map[string]string{
+		"PACKAGE":           filepath.Dir(line.Caller),
+		"SYSLOG_IDENTIFIER": filepath.Base(os.Args[0]),
+	})
+	if err != nil {
+		// "journal" also falls back to stderr
+		// "fmt.Fprintln(os.Stderr, s)"
+		return w.Writer.Write(p)
+	}
+	return 0, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/zap_raft.go b/vendor/github.com/coreos/etcd/pkg/logutil/zap_raft.go
new file mode 100644
index 0000000..012d688
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/zap_raft.go
@@ -0,0 +1,102 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"errors"
+
+	"github.com/coreos/etcd/raft"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+// NewRaftLogger builds "raft.Logger" from "*zap.Config".
+func NewRaftLogger(lcfg *zap.Config) (raft.Logger, error) {
+	if lcfg == nil {
+		return nil, errors.New("nil zap.Config")
+	}
+	lg, err := lcfg.Build(zap.AddCallerSkip(1)) // to annotate caller outside of "logutil"
+	if err != nil {
+		return nil, err
+	}
+	return &zapRaftLogger{lg: lg, sugar: lg.Sugar()}, nil
+}
+
+// NewRaftLoggerZap converts "*zap.Logger" to "raft.Logger".
+func NewRaftLoggerZap(lg *zap.Logger) raft.Logger {
+	return &zapRaftLogger{lg: lg, sugar: lg.Sugar()}
+}
+
+// NewRaftLoggerFromZapCore creates "raft.Logger" from "zap.Core"
+// and "zapcore.WriteSyncer".
+func NewRaftLoggerFromZapCore(cr zapcore.Core, syncer zapcore.WriteSyncer) raft.Logger {
+	// "AddCallerSkip" to annotate caller outside of "logutil"
+	lg := zap.New(cr, zap.AddCaller(), zap.AddCallerSkip(1), zap.ErrorOutput(syncer))
+	return &zapRaftLogger{lg: lg, sugar: lg.Sugar()}
+}
+
+type zapRaftLogger struct {
+	lg    *zap.Logger
+	sugar *zap.SugaredLogger
+}
+
+func (zl *zapRaftLogger) Debug(args ...interface{}) {
+	zl.sugar.Debug(args...)
+}
+
+func (zl *zapRaftLogger) Debugf(format string, args ...interface{}) {
+	zl.sugar.Debugf(format, args...)
+}
+
+func (zl *zapRaftLogger) Error(args ...interface{}) {
+	zl.sugar.Error(args...)
+}
+
+func (zl *zapRaftLogger) Errorf(format string, args ...interface{}) {
+	zl.sugar.Errorf(format, args...)
+}
+
+func (zl *zapRaftLogger) Info(args ...interface{}) {
+	zl.sugar.Info(args...)
+}
+
+func (zl *zapRaftLogger) Infof(format string, args ...interface{}) {
+	zl.sugar.Infof(format, args...)
+}
+
+func (zl *zapRaftLogger) Warning(args ...interface{}) {
+	zl.sugar.Warn(args...)
+}
+
+func (zl *zapRaftLogger) Warningf(format string, args ...interface{}) {
+	zl.sugar.Warnf(format, args...)
+}
+
+func (zl *zapRaftLogger) Fatal(args ...interface{}) {
+	zl.sugar.Fatal(args...)
+}
+
+func (zl *zapRaftLogger) Fatalf(format string, args ...interface{}) {
+	zl.sugar.Fatalf(format, args...)
+}
+
+func (zl *zapRaftLogger) Panic(args ...interface{}) {
+	zl.sugar.Panic(args...)
+}
+
+func (zl *zapRaftLogger) Panicf(format string, args ...interface{}) {
+	zl.sugar.Panicf(format, args...)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/netutil/isolate_linux.go b/vendor/github.com/coreos/etcd/pkg/netutil/isolate_linux.go
new file mode 100644
index 0000000..418580a
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/netutil/isolate_linux.go
@@ -0,0 +1,82 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package netutil
+
+import (
+	"fmt"
+	"os/exec"
+)
+
+// DropPort drops all tcp packets that are received from the given port and sent to the given port.
+func DropPort(port int) error {
+	cmdStr := fmt.Sprintf("sudo iptables -A OUTPUT -p tcp --destination-port %d -j DROP", port)
+	if _, err := exec.Command("/bin/sh", "-c", cmdStr).Output(); err != nil {
+		return err
+	}
+	cmdStr = fmt.Sprintf("sudo iptables -A INPUT -p tcp --destination-port %d -j DROP", port)
+	_, err := exec.Command("/bin/sh", "-c", cmdStr).Output()
+	return err
+}
+
+// RecoverPort stops dropping tcp packets at given port.
+func RecoverPort(port int) error {
+	cmdStr := fmt.Sprintf("sudo iptables -D OUTPUT -p tcp --destination-port %d -j DROP", port)
+	if _, err := exec.Command("/bin/sh", "-c", cmdStr).Output(); err != nil {
+		return err
+	}
+	cmdStr = fmt.Sprintf("sudo iptables -D INPUT -p tcp --destination-port %d -j DROP", port)
+	_, err := exec.Command("/bin/sh", "-c", cmdStr).Output()
+	return err
+}
+
+// SetLatency adds latency in millisecond scale with random variations.
+func SetLatency(ms, rv int) error {
+	ifces, err := GetDefaultInterfaces()
+	if err != nil {
+		return err
+	}
+
+	if rv > ms {
+		rv = 1
+	}
+	for ifce := range ifces {
+		cmdStr := fmt.Sprintf("sudo tc qdisc add dev %s root netem delay %dms %dms distribution normal", ifce, ms, rv)
+		_, err = exec.Command("/bin/sh", "-c", cmdStr).Output()
+		if err != nil {
+			// the rule has already been added. Overwrite it.
+			cmdStr = fmt.Sprintf("sudo tc qdisc change dev %s root netem delay %dms %dms distribution normal", ifce, ms, rv)
+			_, err = exec.Command("/bin/sh", "-c", cmdStr).Output()
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// RemoveLatency resets latency configurations.
+func RemoveLatency() error {
+	ifces, err := GetDefaultInterfaces()
+	if err != nil {
+		return err
+	}
+	for ifce := range ifces {
+		_, err = exec.Command("/bin/sh", "-c", fmt.Sprintf("sudo tc qdisc del dev %s root netem", ifce)).Output()
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/netutil/isolate_stub.go b/vendor/github.com/coreos/etcd/pkg/netutil/isolate_stub.go
new file mode 100644
index 0000000..7f4c3e6
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/netutil/isolate_stub.go
@@ -0,0 +1,25 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !linux
+
+package netutil
+
+func DropPort(port int) error { return nil }
+
+func RecoverPort(port int) error { return nil }
+
+func SetLatency(ms, rv int) error { return nil }
+
+func RemoveLatency() error { return nil }
diff --git a/vendor/github.com/coreos/etcd/pkg/netutil/netutil.go b/vendor/github.com/coreos/etcd/pkg/netutil/netutil.go
new file mode 100644
index 0000000..e3db8c5
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/netutil/netutil.go
@@ -0,0 +1,187 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package netutil implements network-related utility functions.
+package netutil
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/url"
+	"reflect"
+	"sort"
+	"time"
+
+	"github.com/coreos/etcd/pkg/types"
+	"github.com/coreos/pkg/capnslog"
+)
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "pkg/netutil")
+
+	// indirection for testing
+	resolveTCPAddr = resolveTCPAddrDefault
+)
+
+const retryInterval = time.Second
+
+// taken from go's ResolveTCP code but uses configurable ctx
+func resolveTCPAddrDefault(ctx context.Context, addr string) (*net.TCPAddr, error) {
+	host, port, serr := net.SplitHostPort(addr)
+	if serr != nil {
+		return nil, serr
+	}
+	portnum, perr := net.DefaultResolver.LookupPort(ctx, "tcp", port)
+	if perr != nil {
+		return nil, perr
+	}
+
+	var ips []net.IPAddr
+	if ip := net.ParseIP(host); ip != nil {
+		ips = []net.IPAddr{{IP: ip}}
+	} else {
+		// Try as a DNS name.
+		ipss, err := net.DefaultResolver.LookupIPAddr(ctx, host)
+		if err != nil {
+			return nil, err
+		}
+		ips = ipss
+	}
+	// randomize?
+	ip := ips[0]
+	return &net.TCPAddr{IP: ip.IP, Port: portnum, Zone: ip.Zone}, nil
+}
+
+// resolveTCPAddrs is a convenience wrapper for net.ResolveTCPAddr.
+// resolveTCPAddrs return a new set of url.URLs, in which all DNS hostnames
+// are resolved.
+func resolveTCPAddrs(ctx context.Context, urls [][]url.URL) ([][]url.URL, error) {
+	newurls := make([][]url.URL, 0)
+	for _, us := range urls {
+		nus := make([]url.URL, len(us))
+		for i, u := range us {
+			nu, err := url.Parse(u.String())
+			if err != nil {
+				return nil, fmt.Errorf("failed to parse %q (%v)", u.String(), err)
+			}
+			nus[i] = *nu
+		}
+		for i, u := range nus {
+			h, err := resolveURL(ctx, u)
+			if err != nil {
+				return nil, fmt.Errorf("failed to resolve %q (%v)", u.String(), err)
+			}
+			if h != "" {
+				nus[i].Host = h
+			}
+		}
+		newurls = append(newurls, nus)
+	}
+	return newurls, nil
+}
+
+func resolveURL(ctx context.Context, u url.URL) (string, error) {
+	if u.Scheme == "unix" || u.Scheme == "unixs" {
+		// unix sockets don't resolve over TCP
+		return "", nil
+	}
+	host, _, err := net.SplitHostPort(u.Host)
+	if err != nil {
+		plog.Errorf("could not parse url %s during tcp resolving", u.Host)
+		return "", err
+	}
+	if host == "localhost" || net.ParseIP(host) != nil {
+		return "", nil
+	}
+	for ctx.Err() == nil {
+		tcpAddr, err := resolveTCPAddr(ctx, u.Host)
+		if err == nil {
+			plog.Infof("resolving %s to %s", u.Host, tcpAddr.String())
+			return tcpAddr.String(), nil
+		}
+		plog.Warningf("failed resolving host %s (%v); retrying in %v", u.Host, err, retryInterval)
+		select {
+		case <-ctx.Done():
+			plog.Errorf("could not resolve host %s", u.Host)
+			return "", err
+		case <-time.After(retryInterval):
+		}
+	}
+	return "", ctx.Err()
+}
+
+// urlsEqual checks equality of url.URLS between two arrays.
+// This check pass even if an URL is in hostname and opposite is in IP address.
+func urlsEqual(ctx context.Context, a []url.URL, b []url.URL) (bool, error) {
+	if len(a) != len(b) {
+		return false, fmt.Errorf("len(%q) != len(%q)", urlsToStrings(a), urlsToStrings(b))
+	}
+	urls, err := resolveTCPAddrs(ctx, [][]url.URL{a, b})
+	if err != nil {
+		return false, err
+	}
+	preva, prevb := a, b
+	a, b = urls[0], urls[1]
+	sort.Sort(types.URLs(a))
+	sort.Sort(types.URLs(b))
+	for i := range a {
+		if !reflect.DeepEqual(a[i], b[i]) {
+			return false, fmt.Errorf("%q(resolved from %q) != %q(resolved from %q)",
+				a[i].String(), preva[i].String(),
+				b[i].String(), prevb[i].String(),
+			)
+		}
+	}
+	return true, nil
+}
+
+// URLStringsEqual returns "true" if given URLs are valid
+// and resolved to same IP addresses. Otherwise, return "false"
+// and error, if any.
+func URLStringsEqual(ctx context.Context, a []string, b []string) (bool, error) {
+	if len(a) != len(b) {
+		return false, fmt.Errorf("len(%q) != len(%q)", a, b)
+	}
+	urlsA := make([]url.URL, 0)
+	for _, str := range a {
+		u, err := url.Parse(str)
+		if err != nil {
+			return false, fmt.Errorf("failed to parse %q", str)
+		}
+		urlsA = append(urlsA, *u)
+	}
+	urlsB := make([]url.URL, 0)
+	for _, str := range b {
+		u, err := url.Parse(str)
+		if err != nil {
+			return false, fmt.Errorf("failed to parse %q", str)
+		}
+		urlsB = append(urlsB, *u)
+	}
+	return urlsEqual(ctx, urlsA, urlsB)
+}
+
+func urlsToStrings(us []url.URL) []string {
+	rs := make([]string, len(us))
+	for i := range us {
+		rs[i] = us[i].String()
+	}
+	return rs
+}
+
+func IsNetworkTimeoutError(err error) bool {
+	nerr, ok := err.(net.Error)
+	return ok && nerr.Timeout()
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/netutil/routes.go b/vendor/github.com/coreos/etcd/pkg/netutil/routes.go
new file mode 100644
index 0000000..3eb6a19
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/netutil/routes.go
@@ -0,0 +1,33 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !linux
+
+package netutil
+
+import (
+	"fmt"
+	"runtime"
+)
+
+// GetDefaultHost fetches the a resolvable name that corresponds
+// to the machine's default routable interface
+func GetDefaultHost() (string, error) {
+	return "", fmt.Errorf("default host not supported on %s_%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// GetDefaultInterfaces fetches the device name of default routable interface.
+func GetDefaultInterfaces() (map[string]uint8, error) {
+	return nil, fmt.Errorf("default host not supported on %s_%s", runtime.GOOS, runtime.GOARCH)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/netutil/routes_linux.go b/vendor/github.com/coreos/etcd/pkg/netutil/routes_linux.go
new file mode 100644
index 0000000..797baeb
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/netutil/routes_linux.go
@@ -0,0 +1,250 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build linux
+
+package netutil
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"net"
+	"sort"
+	"syscall"
+
+	"github.com/coreos/etcd/pkg/cpuutil"
+)
+
+var errNoDefaultRoute = fmt.Errorf("could not find default route")
+var errNoDefaultHost = fmt.Errorf("could not find default host")
+var errNoDefaultInterface = fmt.Errorf("could not find default interface")
+
+// GetDefaultHost obtains the first IP address of machine from the routing table and returns the IP address as string.
+// An IPv4 address is preferred to an IPv6 address for backward compatibility.
+func GetDefaultHost() (string, error) {
+	rmsgs, rerr := getDefaultRoutes()
+	if rerr != nil {
+		return "", rerr
+	}
+
+	// prioritize IPv4
+	if rmsg, ok := rmsgs[syscall.AF_INET]; ok {
+		if host, err := chooseHost(syscall.AF_INET, rmsg); host != "" || err != nil {
+			return host, err
+		}
+		delete(rmsgs, syscall.AF_INET)
+	}
+
+	// sort so choice is deterministic
+	var families []int
+	for family := range rmsgs {
+		families = append(families, int(family))
+	}
+	sort.Ints(families)
+
+	for _, f := range families {
+		family := uint8(f)
+		if host, err := chooseHost(family, rmsgs[family]); host != "" || err != nil {
+			return host, err
+		}
+	}
+
+	return "", errNoDefaultHost
+}
+
+func chooseHost(family uint8, rmsg *syscall.NetlinkMessage) (string, error) {
+	host, oif, err := parsePREFSRC(rmsg)
+	if host != "" || err != nil {
+		return host, err
+	}
+
+	// prefsrc not detected, fall back to getting address from iface
+	ifmsg, ierr := getIfaceAddr(oif, family)
+	if ierr != nil {
+		return "", ierr
+	}
+
+	attrs, aerr := syscall.ParseNetlinkRouteAttr(ifmsg)
+	if aerr != nil {
+		return "", aerr
+	}
+
+	for _, attr := range attrs {
+		// search for RTA_DST because ipv6 doesn't have RTA_SRC
+		if attr.Attr.Type == syscall.RTA_DST {
+			return net.IP(attr.Value).String(), nil
+		}
+	}
+
+	return "", nil
+}
+
+func getDefaultRoutes() (map[uint8]*syscall.NetlinkMessage, error) {
+	dat, err := syscall.NetlinkRIB(syscall.RTM_GETROUTE, syscall.AF_UNSPEC)
+	if err != nil {
+		return nil, err
+	}
+
+	msgs, msgErr := syscall.ParseNetlinkMessage(dat)
+	if msgErr != nil {
+		return nil, msgErr
+	}
+
+	routes := make(map[uint8]*syscall.NetlinkMessage)
+	rtmsg := syscall.RtMsg{}
+	for _, m := range msgs {
+		if m.Header.Type != syscall.RTM_NEWROUTE {
+			continue
+		}
+		buf := bytes.NewBuffer(m.Data[:syscall.SizeofRtMsg])
+		if rerr := binary.Read(buf, cpuutil.ByteOrder(), &rtmsg); rerr != nil {
+			continue
+		}
+		if rtmsg.Dst_len == 0 && rtmsg.Table == syscall.RT_TABLE_MAIN {
+			// zero-length Dst_len implies default route
+			msg := m
+			routes[rtmsg.Family] = &msg
+		}
+	}
+
+	if len(routes) > 0 {
+		return routes, nil
+	}
+
+	return nil, errNoDefaultRoute
+}
+
+// Used to get an address of interface.
+func getIfaceAddr(idx uint32, family uint8) (*syscall.NetlinkMessage, error) {
+	dat, err := syscall.NetlinkRIB(syscall.RTM_GETADDR, int(family))
+	if err != nil {
+		return nil, err
+	}
+
+	msgs, msgErr := syscall.ParseNetlinkMessage(dat)
+	if msgErr != nil {
+		return nil, msgErr
+	}
+
+	ifaddrmsg := syscall.IfAddrmsg{}
+	for _, m := range msgs {
+		if m.Header.Type != syscall.RTM_NEWADDR {
+			continue
+		}
+		buf := bytes.NewBuffer(m.Data[:syscall.SizeofIfAddrmsg])
+		if rerr := binary.Read(buf, cpuutil.ByteOrder(), &ifaddrmsg); rerr != nil {
+			continue
+		}
+		if ifaddrmsg.Index == idx {
+			return &m, nil
+		}
+	}
+
+	return nil, fmt.Errorf("could not find address for interface index %v", idx)
+
+}
+
+// Used to get a name of interface.
+func getIfaceLink(idx uint32) (*syscall.NetlinkMessage, error) {
+	dat, err := syscall.NetlinkRIB(syscall.RTM_GETLINK, syscall.AF_UNSPEC)
+	if err != nil {
+		return nil, err
+	}
+
+	msgs, msgErr := syscall.ParseNetlinkMessage(dat)
+	if msgErr != nil {
+		return nil, msgErr
+	}
+
+	ifinfomsg := syscall.IfInfomsg{}
+	for _, m := range msgs {
+		if m.Header.Type != syscall.RTM_NEWLINK {
+			continue
+		}
+		buf := bytes.NewBuffer(m.Data[:syscall.SizeofIfInfomsg])
+		if rerr := binary.Read(buf, cpuutil.ByteOrder(), &ifinfomsg); rerr != nil {
+			continue
+		}
+		if ifinfomsg.Index == int32(idx) {
+			return &m, nil
+		}
+	}
+
+	return nil, fmt.Errorf("could not find link for interface index %v", idx)
+}
+
+// GetDefaultInterfaces gets names of interfaces and returns a map[interface]families.
+func GetDefaultInterfaces() (map[string]uint8, error) {
+	interfaces := make(map[string]uint8)
+	rmsgs, rerr := getDefaultRoutes()
+	if rerr != nil {
+		return interfaces, rerr
+	}
+
+	for family, rmsg := range rmsgs {
+		_, oif, err := parsePREFSRC(rmsg)
+		if err != nil {
+			return interfaces, err
+		}
+
+		ifmsg, ierr := getIfaceLink(oif)
+		if ierr != nil {
+			return interfaces, ierr
+		}
+
+		attrs, aerr := syscall.ParseNetlinkRouteAttr(ifmsg)
+		if aerr != nil {
+			return interfaces, aerr
+		}
+
+		for _, attr := range attrs {
+			if attr.Attr.Type == syscall.IFLA_IFNAME {
+				// key is an interface name
+				// possible values: 2 - AF_INET, 10 - AF_INET6, 12 - dualstack
+				interfaces[string(attr.Value[:len(attr.Value)-1])] += family
+			}
+		}
+	}
+	if len(interfaces) > 0 {
+		return interfaces, nil
+	}
+	return interfaces, errNoDefaultInterface
+}
+
+// parsePREFSRC returns preferred source address and output interface index (RTA_OIF).
+func parsePREFSRC(m *syscall.NetlinkMessage) (host string, oif uint32, err error) {
+	var attrs []syscall.NetlinkRouteAttr
+	attrs, err = syscall.ParseNetlinkRouteAttr(m)
+	if err != nil {
+		return "", 0, err
+	}
+
+	for _, attr := range attrs {
+		if attr.Attr.Type == syscall.RTA_PREFSRC {
+			host = net.IP(attr.Value).String()
+		}
+		if attr.Attr.Type == syscall.RTA_OIF {
+			oif = cpuutil.ByteOrder().Uint32(attr.Value)
+		}
+		if host != "" && oif != uint32(0) {
+			break
+		}
+	}
+
+	if oif == 0 {
+		err = errNoDefaultRoute
+	}
+	return host, oif, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/pathutil/path.go b/vendor/github.com/coreos/etcd/pkg/pathutil/path.go
new file mode 100644
index 0000000..f26254b
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/pathutil/path.go
@@ -0,0 +1,31 @@
+// 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.
+
+// Package pathutil implements utility functions for handling slash-separated
+// paths.
+package pathutil
+
+import "path"
+
+// CanonicalURLPath returns the canonical url path for p, which follows the rules:
+// 1. the path always starts with "/"
+// 2. replace multiple slashes with a single slash
+// 3. replace each '.' '..' path name element with equivalent one
+// 4. keep the trailing slash
+// The function is borrowed from stdlib http.cleanPath in server.go.
+func CanonicalURLPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root,
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+	return np
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/pbutil/pbutil.go b/vendor/github.com/coreos/etcd/pkg/pbutil/pbutil.go
new file mode 100644
index 0000000..d70f98d
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/pbutil/pbutil.go
@@ -0,0 +1,60 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package pbutil defines interfaces for handling Protocol Buffer objects.
+package pbutil
+
+import "github.com/coreos/pkg/capnslog"
+
+var (
+	plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "pkg/pbutil")
+)
+
+type Marshaler interface {
+	Marshal() (data []byte, err error)
+}
+
+type Unmarshaler interface {
+	Unmarshal(data []byte) error
+}
+
+func MustMarshal(m Marshaler) []byte {
+	d, err := m.Marshal()
+	if err != nil {
+		plog.Panicf("marshal should never fail (%v)", err)
+	}
+	return d
+}
+
+func MustUnmarshal(um Unmarshaler, data []byte) {
+	if err := um.Unmarshal(data); err != nil {
+		plog.Panicf("unmarshal should never fail (%v)", err)
+	}
+}
+
+func MaybeUnmarshal(um Unmarshaler, data []byte) bool {
+	if err := um.Unmarshal(data); err != nil {
+		return false
+	}
+	return true
+}
+
+func GetBool(v *bool) (vv bool, set bool) {
+	if v == nil {
+		return false, false
+	}
+	return *v, true
+}
+
+func Boolp(b bool) *bool { return &b }
diff --git a/vendor/github.com/coreos/etcd/pkg/runtime/fds_linux.go b/vendor/github.com/coreos/etcd/pkg/runtime/fds_linux.go
new file mode 100644
index 0000000..4906d67
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/runtime/fds_linux.go
@@ -0,0 +1,48 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package runtime implements utility functions for runtime systems.
+package runtime
+
+import (
+	"os"
+	"syscall"
+)
+
+func FDLimit() (uint64, error) {
+	var rlimit syscall.Rlimit
+	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rlimit); err != nil {
+		return 0, err
+	}
+	return rlimit.Cur, nil
+}
+
+func FDUsage() (uint64, error) {
+	return countFiles("/proc/self/fd")
+}
+
+// countFiles reads the directory named by dirname and returns the count.
+// This is same as stdlib "io/ioutil.ReadDir" but without sorting.
+func countFiles(dirname string) (uint64, error) {
+	f, err := os.Open(dirname)
+	if err != nil {
+		return 0, err
+	}
+	list, err := f.Readdir(-1)
+	f.Close()
+	if err != nil {
+		return 0, err
+	}
+	return uint64(len(list)), nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/runtime/fds_other.go b/vendor/github.com/coreos/etcd/pkg/runtime/fds_other.go
new file mode 100644
index 0000000..0cbdb88
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/runtime/fds_other.go
@@ -0,0 +1,30 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !linux
+
+package runtime
+
+import (
+	"fmt"
+	"runtime"
+)
+
+func FDLimit() (uint64, error) {
+	return 0, fmt.Errorf("cannot get FDLimit on %s", runtime.GOOS)
+}
+
+func FDUsage() (uint64, error) {
+	return 0, fmt.Errorf("cannot get FDUsage on %s", runtime.GOOS)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/schedule/doc.go b/vendor/github.com/coreos/etcd/pkg/schedule/doc.go
new file mode 100644
index 0000000..cca2c75
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/schedule/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package schedule provides mechanisms and policies for scheduling units of work.
+package schedule
diff --git a/vendor/github.com/coreos/etcd/pkg/schedule/schedule.go b/vendor/github.com/coreos/etcd/pkg/schedule/schedule.go
new file mode 100644
index 0000000..234d019
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/schedule/schedule.go
@@ -0,0 +1,165 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package schedule
+
+import (
+	"context"
+	"sync"
+)
+
+type Job func(context.Context)
+
+// Scheduler can schedule jobs.
+type Scheduler interface {
+	// Schedule asks the scheduler to schedule a job defined by the given func.
+	// Schedule to a stopped scheduler might panic.
+	Schedule(j Job)
+
+	// Pending returns number of pending jobs
+	Pending() int
+
+	// Scheduled returns the number of scheduled jobs (excluding pending jobs)
+	Scheduled() int
+
+	// Finished returns the number of finished jobs
+	Finished() int
+
+	// WaitFinish waits until at least n job are finished and all pending jobs are finished.
+	WaitFinish(n int)
+
+	// Stop stops the scheduler.
+	Stop()
+}
+
+type fifo struct {
+	mu sync.Mutex
+
+	resume    chan struct{}
+	scheduled int
+	finished  int
+	pendings  []Job
+
+	ctx    context.Context
+	cancel context.CancelFunc
+
+	finishCond *sync.Cond
+	donec      chan struct{}
+}
+
+// NewFIFOScheduler returns a Scheduler that schedules jobs in FIFO
+// order sequentially
+func NewFIFOScheduler() Scheduler {
+	f := &fifo{
+		resume: make(chan struct{}, 1),
+		donec:  make(chan struct{}, 1),
+	}
+	f.finishCond = sync.NewCond(&f.mu)
+	f.ctx, f.cancel = context.WithCancel(context.Background())
+	go f.run()
+	return f
+}
+
+// Schedule schedules a job that will be ran in FIFO order sequentially.
+func (f *fifo) Schedule(j Job) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
+	if f.cancel == nil {
+		panic("schedule: schedule to stopped scheduler")
+	}
+
+	if len(f.pendings) == 0 {
+		select {
+		case f.resume <- struct{}{}:
+		default:
+		}
+	}
+	f.pendings = append(f.pendings, j)
+}
+
+func (f *fifo) Pending() int {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return len(f.pendings)
+}
+
+func (f *fifo) Scheduled() int {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return f.scheduled
+}
+
+func (f *fifo) Finished() int {
+	f.finishCond.L.Lock()
+	defer f.finishCond.L.Unlock()
+	return f.finished
+}
+
+func (f *fifo) WaitFinish(n int) {
+	f.finishCond.L.Lock()
+	for f.finished < n || len(f.pendings) != 0 {
+		f.finishCond.Wait()
+	}
+	f.finishCond.L.Unlock()
+}
+
+// Stop stops the scheduler and cancels all pending jobs.
+func (f *fifo) Stop() {
+	f.mu.Lock()
+	f.cancel()
+	f.cancel = nil
+	f.mu.Unlock()
+	<-f.donec
+}
+
+func (f *fifo) run() {
+	// TODO: recover from job panic?
+	defer func() {
+		close(f.donec)
+		close(f.resume)
+	}()
+
+	for {
+		var todo Job
+		f.mu.Lock()
+		if len(f.pendings) != 0 {
+			f.scheduled++
+			todo = f.pendings[0]
+		}
+		f.mu.Unlock()
+		if todo == nil {
+			select {
+			case <-f.resume:
+			case <-f.ctx.Done():
+				f.mu.Lock()
+				pendings := f.pendings
+				f.pendings = nil
+				f.mu.Unlock()
+				// clean up pending jobs
+				for _, todo := range pendings {
+					todo(f.ctx)
+				}
+				return
+			}
+		} else {
+			todo(f.ctx)
+			f.finishCond.L.Lock()
+			f.finished++
+			f.pendings = f.pendings[1:]
+			f.finishCond.Broadcast()
+			f.finishCond.L.Unlock()
+		}
+	}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/srv/srv.go b/vendor/github.com/coreos/etcd/pkg/srv/srv.go
new file mode 100644
index 0000000..600061c
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/srv/srv.go
@@ -0,0 +1,141 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package srv looks up DNS SRV records.
+package srv
+
+import (
+	"fmt"
+	"net"
+	"net/url"
+	"strings"
+
+	"github.com/coreos/etcd/pkg/types"
+)
+
+var (
+	// indirection for testing
+	lookupSRV      = net.LookupSRV // net.DefaultResolver.LookupSRV when ctxs don't conflict
+	resolveTCPAddr = net.ResolveTCPAddr
+)
+
+// GetCluster gets the cluster information via DNS discovery.
+// Also sees each entry as a separate instance.
+func GetCluster(service, name, dns string, apurls types.URLs) ([]string, error) {
+	tempName := int(0)
+	tcp2ap := make(map[string]url.URL)
+
+	// First, resolve the apurls
+	for _, url := range apurls {
+		tcpAddr, err := resolveTCPAddr("tcp", url.Host)
+		if err != nil {
+			return nil, err
+		}
+		tcp2ap[tcpAddr.String()] = url
+	}
+
+	stringParts := []string{}
+	updateNodeMap := func(service, scheme string) error {
+		_, addrs, err := lookupSRV(service, "tcp", dns)
+		if err != nil {
+			return err
+		}
+		for _, srv := range addrs {
+			port := fmt.Sprintf("%d", srv.Port)
+			host := net.JoinHostPort(srv.Target, port)
+			tcpAddr, terr := resolveTCPAddr("tcp", host)
+			if terr != nil {
+				err = terr
+				continue
+			}
+			n := ""
+			url, ok := tcp2ap[tcpAddr.String()]
+			if ok {
+				n = name
+			}
+			if n == "" {
+				n = fmt.Sprintf("%d", tempName)
+				tempName++
+			}
+			// SRV records have a trailing dot but URL shouldn't.
+			shortHost := strings.TrimSuffix(srv.Target, ".")
+			urlHost := net.JoinHostPort(shortHost, port)
+			if ok && url.Scheme != scheme {
+				err = fmt.Errorf("bootstrap at %s from DNS for %s has scheme mismatch with expected peer %s", scheme+"://"+urlHost, service, url.String())
+			} else {
+				stringParts = append(stringParts, fmt.Sprintf("%s=%s://%s", n, scheme, urlHost))
+			}
+		}
+		if len(stringParts) == 0 {
+			return err
+		}
+		return nil
+	}
+
+	failCount := 0
+	err := updateNodeMap(service+"-ssl", "https")
+	srvErr := make([]string, 2)
+	if err != nil {
+		srvErr[0] = fmt.Sprintf("error querying DNS SRV records for _%s-ssl %s", service, err)
+		failCount++
+	}
+	err = updateNodeMap(service, "http")
+	if err != nil {
+		srvErr[1] = fmt.Sprintf("error querying DNS SRV records for _%s %s", service, err)
+		failCount++
+	}
+	if failCount == 2 {
+		return nil, fmt.Errorf("srv: too many errors querying DNS SRV records (%q, %q)", srvErr[0], srvErr[1])
+	}
+	return stringParts, nil
+}
+
+type SRVClients struct {
+	Endpoints []string
+	SRVs      []*net.SRV
+}
+
+// GetClient looks up the client endpoints for a service and domain.
+func GetClient(service, domain string) (*SRVClients, error) {
+	var urls []*url.URL
+	var srvs []*net.SRV
+
+	updateURLs := func(service, scheme string) error {
+		_, addrs, err := lookupSRV(service, "tcp", domain)
+		if err != nil {
+			return err
+		}
+		for _, srv := range addrs {
+			urls = append(urls, &url.URL{
+				Scheme: scheme,
+				Host:   net.JoinHostPort(srv.Target, fmt.Sprintf("%d", srv.Port)),
+			})
+		}
+		srvs = append(srvs, addrs...)
+		return nil
+	}
+
+	errHTTPS := updateURLs(service+"-ssl", "https")
+	errHTTP := updateURLs(service, "http")
+
+	if errHTTPS != nil && errHTTP != nil {
+		return nil, fmt.Errorf("dns lookup errors: %s and %s", errHTTPS, errHTTP)
+	}
+
+	endpoints := make([]string, len(urls))
+	for i := range urls {
+		endpoints[i] = urls[i].String()
+	}
+	return &SRVClients{Endpoints: endpoints, SRVs: srvs}, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/systemd/doc.go b/vendor/github.com/coreos/etcd/pkg/systemd/doc.go
new file mode 100644
index 0000000..30e77ce
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/systemd/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package systemd provides utility functions for systemd.
+package systemd
diff --git a/vendor/github.com/coreos/etcd/pkg/systemd/journal.go b/vendor/github.com/coreos/etcd/pkg/systemd/journal.go
new file mode 100644
index 0000000..b861c69
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/systemd/journal.go
@@ -0,0 +1,29 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package systemd
+
+import "net"
+
+// DialJournal returns no error if the process can dial journal socket.
+// Returns an error if dial failed, whichi indicates journald is not available
+// (e.g. run embedded etcd as docker daemon).
+// Reference: https://github.com/coreos/go-systemd/blob/master/journal/journal.go.
+func DialJournal() error {
+	conn, err := net.Dial("unixgram", "/run/systemd/journal/socket")
+	if conn != nil {
+		defer conn.Close()
+	}
+	return err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/tlsutil/cipher_suites.go b/vendor/github.com/coreos/etcd/pkg/tlsutil/cipher_suites.go
new file mode 100644
index 0000000..b5916bb
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/tlsutil/cipher_suites.go
@@ -0,0 +1,51 @@
+// Copyright 2018 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tlsutil
+
+import "crypto/tls"
+
+// cipher suites implemented by Go
+// https://github.com/golang/go/blob/dev.boringcrypto.go1.10/src/crypto/tls/cipher_suites.go
+var cipherSuites = map[string]uint16{
+	"TLS_RSA_WITH_RC4_128_SHA":                tls.TLS_RSA_WITH_RC4_128_SHA,
+	"TLS_RSA_WITH_3DES_EDE_CBC_SHA":           tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+	"TLS_RSA_WITH_AES_128_CBC_SHA":            tls.TLS_RSA_WITH_AES_128_CBC_SHA,
+	"TLS_RSA_WITH_AES_256_CBC_SHA":            tls.TLS_RSA_WITH_AES_256_CBC_SHA,
+	"TLS_RSA_WITH_AES_128_CBC_SHA256":         tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
+	"TLS_RSA_WITH_AES_128_GCM_SHA256":         tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
+	"TLS_RSA_WITH_AES_256_GCM_SHA384":         tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
+	"TLS_ECDHE_ECDSA_WITH_RC4_128_SHA":        tls.TLS_ECDHE_ECDSA_WITH_RC4_128_SHA,
+	"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+	"TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA":    tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+	"TLS_ECDHE_RSA_WITH_RC4_128_SHA":          tls.TLS_ECDHE_RSA_WITH_RC4_128_SHA,
+	"TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA":     tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+	"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA":      tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+	"TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA":      tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+	"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+	"TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+	"TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256":   tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+	"TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256": tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+	"TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384":   tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+	"TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384": tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
+	"TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305":    tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
+	"TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305":  tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
+}
+
+// GetCipherSuite returns the corresponding cipher suite,
+// and boolean value if it is supported.
+func GetCipherSuite(s string) (uint16, bool) {
+	v, ok := cipherSuites[s]
+	return v, ok
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/tlsutil/doc.go b/vendor/github.com/coreos/etcd/pkg/tlsutil/doc.go
new file mode 100644
index 0000000..3b6aa67
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/tlsutil/doc.go
@@ -0,0 +1,16 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package tlsutil provides utility functions for handling TLS.
+package tlsutil
diff --git a/vendor/github.com/coreos/etcd/pkg/tlsutil/tlsutil.go b/vendor/github.com/coreos/etcd/pkg/tlsutil/tlsutil.go
new file mode 100644
index 0000000..79b1f63
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/tlsutil/tlsutil.go
@@ -0,0 +1,72 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package tlsutil
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/pem"
+	"io/ioutil"
+)
+
+// NewCertPool creates x509 certPool with provided CA files.
+func NewCertPool(CAFiles []string) (*x509.CertPool, error) {
+	certPool := x509.NewCertPool()
+
+	for _, CAFile := range CAFiles {
+		pemByte, err := ioutil.ReadFile(CAFile)
+		if err != nil {
+			return nil, err
+		}
+
+		for {
+			var block *pem.Block
+			block, pemByte = pem.Decode(pemByte)
+			if block == nil {
+				break
+			}
+			cert, err := x509.ParseCertificate(block.Bytes)
+			if err != nil {
+				return nil, err
+			}
+			certPool.AddCert(cert)
+		}
+	}
+
+	return certPool, nil
+}
+
+// NewCert generates TLS cert by using the given cert,key and parse function.
+func NewCert(certfile, keyfile string, parseFunc func([]byte, []byte) (tls.Certificate, error)) (*tls.Certificate, error) {
+	cert, err := ioutil.ReadFile(certfile)
+	if err != nil {
+		return nil, err
+	}
+
+	key, err := ioutil.ReadFile(keyfile)
+	if err != nil {
+		return nil, err
+	}
+
+	if parseFunc == nil {
+		parseFunc = tls.X509KeyPair
+	}
+
+	tlsCert, err := parseFunc(cert, key)
+	if err != nil {
+		return nil, err
+	}
+	return &tlsCert, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/doc.go b/vendor/github.com/coreos/etcd/pkg/transport/doc.go
new file mode 100644
index 0000000..37658ce
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/doc.go
@@ -0,0 +1,17 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package transport implements various HTTP transport utilities based on Go
+// net package.
+package transport
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/keepalive_listener.go b/vendor/github.com/coreos/etcd/pkg/transport/keepalive_listener.go
new file mode 100644
index 0000000..4ff8e7f
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/keepalive_listener.go
@@ -0,0 +1,94 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"crypto/tls"
+	"fmt"
+	"net"
+	"time"
+)
+
+type keepAliveConn interface {
+	SetKeepAlive(bool) error
+	SetKeepAlivePeriod(d time.Duration) error
+}
+
+// NewKeepAliveListener returns a listener that listens on the given address.
+// Be careful when wrap around KeepAliveListener with another Listener if TLSInfo is not nil.
+// Some pkgs (like go/http) might expect Listener to return TLSConn type to start TLS handshake.
+// http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html
+func NewKeepAliveListener(l net.Listener, scheme string, tlscfg *tls.Config) (net.Listener, error) {
+	if scheme == "https" {
+		if tlscfg == nil {
+			return nil, fmt.Errorf("cannot listen on TLS for given listener: KeyFile and CertFile are not presented")
+		}
+		return newTLSKeepaliveListener(l, tlscfg), nil
+	}
+
+	return &keepaliveListener{
+		Listener: l,
+	}, nil
+}
+
+type keepaliveListener struct{ net.Listener }
+
+func (kln *keepaliveListener) Accept() (net.Conn, error) {
+	c, err := kln.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+	kac := c.(keepAliveConn)
+	// detection time: tcp_keepalive_time + tcp_keepalive_probes + tcp_keepalive_intvl
+	// default on linux:  30 + 8 * 30
+	// default on osx:    30 + 8 * 75
+	kac.SetKeepAlive(true)
+	kac.SetKeepAlivePeriod(30 * time.Second)
+	return c, nil
+}
+
+// A tlsKeepaliveListener implements a network listener (net.Listener) for TLS connections.
+type tlsKeepaliveListener struct {
+	net.Listener
+	config *tls.Config
+}
+
+// Accept waits for and returns the next incoming TLS connection.
+// The returned connection c is a *tls.Conn.
+func (l *tlsKeepaliveListener) Accept() (c net.Conn, err error) {
+	c, err = l.Listener.Accept()
+	if err != nil {
+		return
+	}
+	kac := c.(keepAliveConn)
+	// detection time: tcp_keepalive_time + tcp_keepalive_probes + tcp_keepalive_intvl
+	// default on linux:  30 + 8 * 30
+	// default on osx:    30 + 8 * 75
+	kac.SetKeepAlive(true)
+	kac.SetKeepAlivePeriod(30 * time.Second)
+	c = tls.Server(c, l.config)
+	return c, nil
+}
+
+// NewListener creates a Listener which accepts connections from an inner
+// Listener and wraps each connection with Server.
+// The configuration config must be non-nil and must have
+// at least one certificate.
+func newTLSKeepaliveListener(inner net.Listener, config *tls.Config) net.Listener {
+	l := &tlsKeepaliveListener{}
+	l.Listener = inner
+	l.config = config
+	return l
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/limit_listen.go b/vendor/github.com/coreos/etcd/pkg/transport/limit_listen.go
new file mode 100644
index 0000000..930c542
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/limit_listen.go
@@ -0,0 +1,80 @@
+// Copyright 2013 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package transport provides network utility functions, complementing the more
+// common ones in the net package.
+package transport
+
+import (
+	"errors"
+	"net"
+	"sync"
+	"time"
+)
+
+var (
+	ErrNotTCP = errors.New("only tcp connections have keepalive")
+)
+
+// LimitListener returns a Listener that accepts at most n simultaneous
+// connections from the provided Listener.
+func LimitListener(l net.Listener, n int) net.Listener {
+	return &limitListener{l, make(chan struct{}, n)}
+}
+
+type limitListener struct {
+	net.Listener
+	sem chan struct{}
+}
+
+func (l *limitListener) acquire() { l.sem <- struct{}{} }
+func (l *limitListener) release() { <-l.sem }
+
+func (l *limitListener) Accept() (net.Conn, error) {
+	l.acquire()
+	c, err := l.Listener.Accept()
+	if err != nil {
+		l.release()
+		return nil, err
+	}
+	return &limitListenerConn{Conn: c, release: l.release}, nil
+}
+
+type limitListenerConn struct {
+	net.Conn
+	releaseOnce sync.Once
+	release     func()
+}
+
+func (l *limitListenerConn) Close() error {
+	err := l.Conn.Close()
+	l.releaseOnce.Do(l.release)
+	return err
+}
+
+func (l *limitListenerConn) SetKeepAlive(doKeepAlive bool) error {
+	tcpc, ok := l.Conn.(*net.TCPConn)
+	if !ok {
+		return ErrNotTCP
+	}
+	return tcpc.SetKeepAlive(doKeepAlive)
+}
+
+func (l *limitListenerConn) SetKeepAlivePeriod(d time.Duration) error {
+	tcpc, ok := l.Conn.(*net.TCPConn)
+	if !ok {
+		return ErrNotTCP
+	}
+	return tcpc.SetKeepAlivePeriod(d)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/listener.go b/vendor/github.com/coreos/etcd/pkg/transport/listener.go
new file mode 100644
index 0000000..5e0d87a
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/listener.go
@@ -0,0 +1,296 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"math/big"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/coreos/etcd/pkg/fileutil"
+	"github.com/coreos/etcd/pkg/tlsutil"
+)
+
+func NewListener(addr, scheme string, tlsinfo *TLSInfo) (l net.Listener, err error) {
+	if l, err = newListener(addr, scheme); err != nil {
+		return nil, err
+	}
+	return wrapTLS(addr, scheme, tlsinfo, l)
+}
+
+func newListener(addr string, scheme string) (net.Listener, error) {
+	if scheme == "unix" || scheme == "unixs" {
+		// unix sockets via unix://laddr
+		return NewUnixListener(addr)
+	}
+	return net.Listen("tcp", addr)
+}
+
+func wrapTLS(addr, scheme string, tlsinfo *TLSInfo, l net.Listener) (net.Listener, error) {
+	if scheme != "https" && scheme != "unixs" {
+		return l, nil
+	}
+	if tlsinfo != nil && tlsinfo.SkipClientSANVerify {
+		return NewTLSListener(l, tlsinfo)
+	}
+	return newTLSListener(l, tlsinfo, checkSAN)
+}
+
+type TLSInfo struct {
+	CertFile           string
+	KeyFile            string
+	CAFile             string // TODO: deprecate this in v4
+	TrustedCAFile      string
+	ClientCertAuth     bool
+	CRLFile            string
+	InsecureSkipVerify bool
+
+	SkipClientSANVerify bool
+
+	// ServerName ensures the cert matches the given host in case of discovery / virtual hosting
+	ServerName string
+
+	// HandshakeFailure is optionally called when a connection fails to handshake. The
+	// connection will be closed immediately afterwards.
+	HandshakeFailure func(*tls.Conn, error)
+
+	// CipherSuites is a list of supported cipher suites.
+	// If empty, Go auto-populates it by default.
+	// Note that cipher suites are prioritized in the given order.
+	CipherSuites []uint16
+
+	selfCert bool
+
+	// parseFunc exists to simplify testing. Typically, parseFunc
+	// should be left nil. In that case, tls.X509KeyPair will be used.
+	parseFunc func([]byte, []byte) (tls.Certificate, error)
+
+	// AllowedCN is a CN which must be provided by a client.
+	AllowedCN string
+}
+
+func (info TLSInfo) String() string {
+	return fmt.Sprintf("cert = %s, key = %s, ca = %s, trusted-ca = %s, client-cert-auth = %v, crl-file = %s", info.CertFile, info.KeyFile, info.CAFile, info.TrustedCAFile, info.ClientCertAuth, info.CRLFile)
+}
+
+func (info TLSInfo) Empty() bool {
+	return info.CertFile == "" && info.KeyFile == ""
+}
+
+func SelfCert(dirpath string, hosts []string, additionalUsages ...x509.ExtKeyUsage) (info TLSInfo, err error) {
+	err = fileutil.TouchDirAll(dirpath)
+	if err != nil {
+		return
+	}
+
+	certPath := filepath.Join(dirpath, "cert.pem")
+	keyPath := filepath.Join(dirpath, "key.pem")
+	_, errcert := os.Stat(certPath)
+	_, errkey := os.Stat(keyPath)
+	if errcert == nil && errkey == nil {
+		info.CertFile = certPath
+		info.KeyFile = keyPath
+		info.selfCert = true
+		return
+	}
+
+	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
+	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
+	if err != nil {
+		return
+	}
+
+	tmpl := x509.Certificate{
+		SerialNumber: serialNumber,
+		Subject:      pkix.Name{Organization: []string{"etcd"}},
+		NotBefore:    time.Now(),
+		NotAfter:     time.Now().Add(365 * (24 * time.Hour)),
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           append([]x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}, additionalUsages...),
+		BasicConstraintsValid: true,
+	}
+
+	for _, host := range hosts {
+		h, _, _ := net.SplitHostPort(host)
+		if ip := net.ParseIP(h); ip != nil {
+			tmpl.IPAddresses = append(tmpl.IPAddresses, ip)
+		} else {
+			tmpl.DNSNames = append(tmpl.DNSNames, h)
+		}
+	}
+
+	priv, err := ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
+	if err != nil {
+		return
+	}
+
+	derBytes, err := x509.CreateCertificate(rand.Reader, &tmpl, &tmpl, &priv.PublicKey, priv)
+	if err != nil {
+		return
+	}
+
+	certOut, err := os.Create(certPath)
+	if err != nil {
+		return
+	}
+	pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+	certOut.Close()
+
+	b, err := x509.MarshalECPrivateKey(priv)
+	if err != nil {
+		return
+	}
+	keyOut, err := os.OpenFile(keyPath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
+	if err != nil {
+		return
+	}
+	pem.Encode(keyOut, &pem.Block{Type: "EC PRIVATE KEY", Bytes: b})
+	keyOut.Close()
+
+	return SelfCert(dirpath, hosts)
+}
+
+func (info TLSInfo) baseConfig() (*tls.Config, error) {
+	if info.KeyFile == "" || info.CertFile == "" {
+		return nil, fmt.Errorf("KeyFile and CertFile must both be present[key: %v, cert: %v]", info.KeyFile, info.CertFile)
+	}
+
+	_, err := tlsutil.NewCert(info.CertFile, info.KeyFile, info.parseFunc)
+	if err != nil {
+		return nil, err
+	}
+
+	cfg := &tls.Config{
+		MinVersion: tls.VersionTLS12,
+		ServerName: info.ServerName,
+	}
+
+	if len(info.CipherSuites) > 0 {
+		cfg.CipherSuites = info.CipherSuites
+	}
+
+	if info.AllowedCN != "" {
+		cfg.VerifyPeerCertificate = func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error {
+			for _, chains := range verifiedChains {
+				if len(chains) != 0 {
+					if info.AllowedCN == chains[0].Subject.CommonName {
+						return nil
+					}
+				}
+			}
+			return errors.New("CommonName authentication failed")
+		}
+	}
+
+	// this only reloads certs when there's a client request
+	// TODO: support server-side refresh (e.g. inotify, SIGHUP), caching
+	cfg.GetCertificate = func(clientHello *tls.ClientHelloInfo) (*tls.Certificate, error) {
+		return tlsutil.NewCert(info.CertFile, info.KeyFile, info.parseFunc)
+	}
+	cfg.GetClientCertificate = func(unused *tls.CertificateRequestInfo) (*tls.Certificate, error) {
+		return tlsutil.NewCert(info.CertFile, info.KeyFile, info.parseFunc)
+	}
+	return cfg, nil
+}
+
+// cafiles returns a list of CA file paths.
+func (info TLSInfo) cafiles() []string {
+	cs := make([]string, 0)
+	if info.CAFile != "" {
+		cs = append(cs, info.CAFile)
+	}
+	if info.TrustedCAFile != "" {
+		cs = append(cs, info.TrustedCAFile)
+	}
+	return cs
+}
+
+// ServerConfig generates a tls.Config object for use by an HTTP server.
+func (info TLSInfo) ServerConfig() (*tls.Config, error) {
+	cfg, err := info.baseConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	cfg.ClientAuth = tls.NoClientCert
+	if info.CAFile != "" || info.ClientCertAuth {
+		cfg.ClientAuth = tls.RequireAndVerifyClientCert
+	}
+
+	CAFiles := info.cafiles()
+	if len(CAFiles) > 0 {
+		cp, err := tlsutil.NewCertPool(CAFiles)
+		if err != nil {
+			return nil, err
+		}
+		cfg.ClientCAs = cp
+	}
+
+	// "h2" NextProtos is necessary for enabling HTTP2 for go's HTTP server
+	cfg.NextProtos = []string{"h2"}
+
+	return cfg, nil
+}
+
+// ClientConfig generates a tls.Config object for use by an HTTP client.
+func (info TLSInfo) ClientConfig() (*tls.Config, error) {
+	var cfg *tls.Config
+	var err error
+
+	if !info.Empty() {
+		cfg, err = info.baseConfig()
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		cfg = &tls.Config{ServerName: info.ServerName}
+	}
+	cfg.InsecureSkipVerify = info.InsecureSkipVerify
+
+	CAFiles := info.cafiles()
+	if len(CAFiles) > 0 {
+		cfg.RootCAs, err = tlsutil.NewCertPool(CAFiles)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if info.selfCert {
+		cfg.InsecureSkipVerify = true
+	}
+	return cfg, nil
+}
+
+// IsClosedConnError returns true if the error is from closing listener, cmux.
+// copied from golang.org/x/net/http2/http2.go
+func IsClosedConnError(err error) bool {
+	// 'use of closed network connection' (Go <=1.8)
+	// 'use of closed file or network connection' (Go >1.8, internal/poll.ErrClosing)
+	// 'mux: listener closed' (cmux.ErrListenerClosed)
+	return err != nil && strings.Contains(err.Error(), "closed")
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/listener_tls.go b/vendor/github.com/coreos/etcd/pkg/transport/listener_tls.go
new file mode 100644
index 0000000..6f16009
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/listener_tls.go
@@ -0,0 +1,272 @@
+// Copyright 2017 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"strings"
+	"sync"
+)
+
+// tlsListener overrides a TLS listener so it will reject client
+// certificates with insufficient SAN credentials or CRL revoked
+// certificates.
+type tlsListener struct {
+	net.Listener
+	connc            chan net.Conn
+	donec            chan struct{}
+	err              error
+	handshakeFailure func(*tls.Conn, error)
+	check            tlsCheckFunc
+}
+
+type tlsCheckFunc func(context.Context, *tls.Conn) error
+
+// NewTLSListener handshakes TLS connections and performs optional CRL checking.
+func NewTLSListener(l net.Listener, tlsinfo *TLSInfo) (net.Listener, error) {
+	check := func(context.Context, *tls.Conn) error { return nil }
+	return newTLSListener(l, tlsinfo, check)
+}
+
+func newTLSListener(l net.Listener, tlsinfo *TLSInfo, check tlsCheckFunc) (net.Listener, error) {
+	if tlsinfo == nil || tlsinfo.Empty() {
+		l.Close()
+		return nil, fmt.Errorf("cannot listen on TLS for %s: KeyFile and CertFile are not presented", l.Addr().String())
+	}
+	tlscfg, err := tlsinfo.ServerConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	hf := tlsinfo.HandshakeFailure
+	if hf == nil {
+		hf = func(*tls.Conn, error) {}
+	}
+
+	if len(tlsinfo.CRLFile) > 0 {
+		prevCheck := check
+		check = func(ctx context.Context, tlsConn *tls.Conn) error {
+			if err := prevCheck(ctx, tlsConn); err != nil {
+				return err
+			}
+			st := tlsConn.ConnectionState()
+			if certs := st.PeerCertificates; len(certs) > 0 {
+				return checkCRL(tlsinfo.CRLFile, certs)
+			}
+			return nil
+		}
+	}
+
+	tlsl := &tlsListener{
+		Listener:         tls.NewListener(l, tlscfg),
+		connc:            make(chan net.Conn),
+		donec:            make(chan struct{}),
+		handshakeFailure: hf,
+		check:            check,
+	}
+	go tlsl.acceptLoop()
+	return tlsl, nil
+}
+
+func (l *tlsListener) Accept() (net.Conn, error) {
+	select {
+	case conn := <-l.connc:
+		return conn, nil
+	case <-l.donec:
+		return nil, l.err
+	}
+}
+
+func checkSAN(ctx context.Context, tlsConn *tls.Conn) error {
+	st := tlsConn.ConnectionState()
+	if certs := st.PeerCertificates; len(certs) > 0 {
+		addr := tlsConn.RemoteAddr().String()
+		return checkCertSAN(ctx, certs[0], addr)
+	}
+	return nil
+}
+
+// acceptLoop launches each TLS handshake in a separate goroutine
+// to prevent a hanging TLS connection from blocking other connections.
+func (l *tlsListener) acceptLoop() {
+	var wg sync.WaitGroup
+	var pendingMu sync.Mutex
+
+	pending := make(map[net.Conn]struct{})
+	ctx, cancel := context.WithCancel(context.Background())
+	defer func() {
+		cancel()
+		pendingMu.Lock()
+		for c := range pending {
+			c.Close()
+		}
+		pendingMu.Unlock()
+		wg.Wait()
+		close(l.donec)
+	}()
+
+	for {
+		conn, err := l.Listener.Accept()
+		if err != nil {
+			l.err = err
+			return
+		}
+
+		pendingMu.Lock()
+		pending[conn] = struct{}{}
+		pendingMu.Unlock()
+
+		wg.Add(1)
+		go func() {
+			defer func() {
+				if conn != nil {
+					conn.Close()
+				}
+				wg.Done()
+			}()
+
+			tlsConn := conn.(*tls.Conn)
+			herr := tlsConn.Handshake()
+			pendingMu.Lock()
+			delete(pending, conn)
+			pendingMu.Unlock()
+
+			if herr != nil {
+				l.handshakeFailure(tlsConn, herr)
+				return
+			}
+			if err := l.check(ctx, tlsConn); err != nil {
+				l.handshakeFailure(tlsConn, err)
+				return
+			}
+
+			select {
+			case l.connc <- tlsConn:
+				conn = nil
+			case <-ctx.Done():
+			}
+		}()
+	}
+}
+
+func checkCRL(crlPath string, cert []*x509.Certificate) error {
+	// TODO: cache
+	crlBytes, err := ioutil.ReadFile(crlPath)
+	if err != nil {
+		return err
+	}
+	certList, err := x509.ParseCRL(crlBytes)
+	if err != nil {
+		return err
+	}
+	revokedSerials := make(map[string]struct{})
+	for _, rc := range certList.TBSCertList.RevokedCertificates {
+		revokedSerials[string(rc.SerialNumber.Bytes())] = struct{}{}
+	}
+	for _, c := range cert {
+		serial := string(c.SerialNumber.Bytes())
+		if _, ok := revokedSerials[serial]; ok {
+			return fmt.Errorf("transport: certificate serial %x revoked", serial)
+		}
+	}
+	return nil
+}
+
+func checkCertSAN(ctx context.Context, cert *x509.Certificate, remoteAddr string) error {
+	if len(cert.IPAddresses) == 0 && len(cert.DNSNames) == 0 {
+		return nil
+	}
+	h, _, herr := net.SplitHostPort(remoteAddr)
+	if herr != nil {
+		return herr
+	}
+	if len(cert.IPAddresses) > 0 {
+		cerr := cert.VerifyHostname(h)
+		if cerr == nil {
+			return nil
+		}
+		if len(cert.DNSNames) == 0 {
+			return cerr
+		}
+	}
+	if len(cert.DNSNames) > 0 {
+		ok, err := isHostInDNS(ctx, h, cert.DNSNames)
+		if ok {
+			return nil
+		}
+		errStr := ""
+		if err != nil {
+			errStr = " (" + err.Error() + ")"
+		}
+		return fmt.Errorf("tls: %q does not match any of DNSNames %q"+errStr, h, cert.DNSNames)
+	}
+	return nil
+}
+
+func isHostInDNS(ctx context.Context, host string, dnsNames []string) (ok bool, err error) {
+	// reverse lookup
+	wildcards, names := []string{}, []string{}
+	for _, dns := range dnsNames {
+		if strings.HasPrefix(dns, "*.") {
+			wildcards = append(wildcards, dns[1:])
+		} else {
+			names = append(names, dns)
+		}
+	}
+	lnames, lerr := net.DefaultResolver.LookupAddr(ctx, host)
+	for _, name := range lnames {
+		// strip trailing '.' from PTR record
+		if name[len(name)-1] == '.' {
+			name = name[:len(name)-1]
+		}
+		for _, wc := range wildcards {
+			if strings.HasSuffix(name, wc) {
+				return true, nil
+			}
+		}
+		for _, n := range names {
+			if n == name {
+				return true, nil
+			}
+		}
+	}
+	err = lerr
+
+	// forward lookup
+	for _, dns := range names {
+		addrs, lerr := net.DefaultResolver.LookupHost(ctx, dns)
+		if lerr != nil {
+			err = lerr
+			continue
+		}
+		for _, addr := range addrs {
+			if addr == host {
+				return true, nil
+			}
+		}
+	}
+	return false, err
+}
+
+func (l *tlsListener) Close() error {
+	err := l.Listener.Close()
+	<-l.donec
+	return err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/timeout_conn.go b/vendor/github.com/coreos/etcd/pkg/transport/timeout_conn.go
new file mode 100644
index 0000000..7e8c020
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/timeout_conn.go
@@ -0,0 +1,44 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"time"
+)
+
+type timeoutConn struct {
+	net.Conn
+	wtimeoutd  time.Duration
+	rdtimeoutd time.Duration
+}
+
+func (c timeoutConn) Write(b []byte) (n int, err error) {
+	if c.wtimeoutd > 0 {
+		if err := c.SetWriteDeadline(time.Now().Add(c.wtimeoutd)); err != nil {
+			return 0, err
+		}
+	}
+	return c.Conn.Write(b)
+}
+
+func (c timeoutConn) Read(b []byte) (n int, err error) {
+	if c.rdtimeoutd > 0 {
+		if err := c.SetReadDeadline(time.Now().Add(c.rdtimeoutd)); err != nil {
+			return 0, err
+		}
+	}
+	return c.Conn.Read(b)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/timeout_dialer.go b/vendor/github.com/coreos/etcd/pkg/transport/timeout_dialer.go
new file mode 100644
index 0000000..6ae39ec
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/timeout_dialer.go
@@ -0,0 +1,36 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"time"
+)
+
+type rwTimeoutDialer struct {
+	wtimeoutd  time.Duration
+	rdtimeoutd time.Duration
+	net.Dialer
+}
+
+func (d *rwTimeoutDialer) Dial(network, address string) (net.Conn, error) {
+	conn, err := d.Dialer.Dial(network, address)
+	tconn := &timeoutConn{
+		rdtimeoutd: d.rdtimeoutd,
+		wtimeoutd:  d.wtimeoutd,
+		Conn:       conn,
+	}
+	return tconn, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/timeout_listener.go b/vendor/github.com/coreos/etcd/pkg/transport/timeout_listener.go
new file mode 100644
index 0000000..b35e049
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/timeout_listener.go
@@ -0,0 +1,57 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"time"
+)
+
+// NewTimeoutListener returns a listener that listens on the given address.
+// If read/write on the accepted connection blocks longer than its time limit,
+// it will return timeout error.
+func NewTimeoutListener(addr string, scheme string, tlsinfo *TLSInfo, rdtimeoutd, wtimeoutd time.Duration) (net.Listener, error) {
+	ln, err := newListener(addr, scheme)
+	if err != nil {
+		return nil, err
+	}
+	ln = &rwTimeoutListener{
+		Listener:   ln,
+		rdtimeoutd: rdtimeoutd,
+		wtimeoutd:  wtimeoutd,
+	}
+	if ln, err = wrapTLS(addr, scheme, tlsinfo, ln); err != nil {
+		return nil, err
+	}
+	return ln, nil
+}
+
+type rwTimeoutListener struct {
+	net.Listener
+	wtimeoutd  time.Duration
+	rdtimeoutd time.Duration
+}
+
+func (rwln *rwTimeoutListener) Accept() (net.Conn, error) {
+	c, err := rwln.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+	return timeoutConn{
+		Conn:       c,
+		wtimeoutd:  rwln.wtimeoutd,
+		rdtimeoutd: rwln.rdtimeoutd,
+	}, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/timeout_transport.go b/vendor/github.com/coreos/etcd/pkg/transport/timeout_transport.go
new file mode 100644
index 0000000..ea16b4c
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/timeout_transport.go
@@ -0,0 +1,51 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"net/http"
+	"time"
+)
+
+// NewTimeoutTransport returns a transport created using the given TLS info.
+// If read/write on the created connection blocks longer than its time limit,
+// it will return timeout error.
+// If read/write timeout is set, transport will not be able to reuse connection.
+func NewTimeoutTransport(info TLSInfo, dialtimeoutd, rdtimeoutd, wtimeoutd time.Duration) (*http.Transport, error) {
+	tr, err := NewTransport(info, dialtimeoutd)
+	if err != nil {
+		return nil, err
+	}
+
+	if rdtimeoutd != 0 || wtimeoutd != 0 {
+		// the timed out connection will timeout soon after it is idle.
+		// it should not be put back to http transport as an idle connection for future usage.
+		tr.MaxIdleConnsPerHost = -1
+	} else {
+		// allow more idle connections between peers to avoid unnecessary port allocation.
+		tr.MaxIdleConnsPerHost = 1024
+	}
+
+	tr.Dial = (&rwTimeoutDialer{
+		Dialer: net.Dialer{
+			Timeout:   dialtimeoutd,
+			KeepAlive: 30 * time.Second,
+		},
+		rdtimeoutd: rdtimeoutd,
+		wtimeoutd:  wtimeoutd,
+	}).Dial
+	return tr, nil
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/tls.go b/vendor/github.com/coreos/etcd/pkg/transport/tls.go
new file mode 100644
index 0000000..62fe0d3
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/tls.go
@@ -0,0 +1,49 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"fmt"
+	"strings"
+	"time"
+)
+
+// ValidateSecureEndpoints scans the given endpoints against tls info, returning only those
+// endpoints that could be validated as secure.
+func ValidateSecureEndpoints(tlsInfo TLSInfo, eps []string) ([]string, error) {
+	t, err := NewTransport(tlsInfo, 5*time.Second)
+	if err != nil {
+		return nil, err
+	}
+	var errs []string
+	var endpoints []string
+	for _, ep := range eps {
+		if !strings.HasPrefix(ep, "https://") {
+			errs = append(errs, fmt.Sprintf("%q is insecure", ep))
+			continue
+		}
+		conn, cerr := t.Dial("tcp", ep[len("https://"):])
+		if cerr != nil {
+			errs = append(errs, fmt.Sprintf("%q failed to dial (%v)", ep, cerr))
+			continue
+		}
+		conn.Close()
+		endpoints = append(endpoints, ep)
+	}
+	if len(errs) != 0 {
+		err = fmt.Errorf("%s", strings.Join(errs, ","))
+	}
+	return endpoints, err
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/transport.go b/vendor/github.com/coreos/etcd/pkg/transport/transport.go
new file mode 100644
index 0000000..4a7fe69
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/transport.go
@@ -0,0 +1,71 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"net/http"
+	"strings"
+	"time"
+)
+
+type unixTransport struct{ *http.Transport }
+
+func NewTransport(info TLSInfo, dialtimeoutd time.Duration) (*http.Transport, error) {
+	cfg, err := info.ClientConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	t := &http.Transport{
+		Proxy: http.ProxyFromEnvironment,
+		Dial: (&net.Dialer{
+			Timeout: dialtimeoutd,
+			// value taken from http.DefaultTransport
+			KeepAlive: 30 * time.Second,
+		}).Dial,
+		// value taken from http.DefaultTransport
+		TLSHandshakeTimeout: 10 * time.Second,
+		TLSClientConfig:     cfg,
+	}
+
+	dialer := (&net.Dialer{
+		Timeout:   dialtimeoutd,
+		KeepAlive: 30 * time.Second,
+	})
+	dial := func(net, addr string) (net.Conn, error) {
+		return dialer.Dial("unix", addr)
+	}
+
+	tu := &http.Transport{
+		Proxy:               http.ProxyFromEnvironment,
+		Dial:                dial,
+		TLSHandshakeTimeout: 10 * time.Second,
+		TLSClientConfig:     cfg,
+	}
+	ut := &unixTransport{tu}
+
+	t.RegisterProtocol("unix", ut)
+	t.RegisterProtocol("unixs", ut)
+
+	return t, nil
+}
+
+func (urt *unixTransport) RoundTrip(req *http.Request) (*http.Response, error) {
+	url := *req.URL
+	req.URL = &url
+	req.URL.Scheme = strings.Replace(req.URL.Scheme, "unix", "http", 1)
+	return urt.Transport.RoundTrip(req)
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/transport/unix_listener.go b/vendor/github.com/coreos/etcd/pkg/transport/unix_listener.go
new file mode 100644
index 0000000..123e203
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/transport/unix_listener.go
@@ -0,0 +1,40 @@
+// Copyright 2016 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package transport
+
+import (
+	"net"
+	"os"
+)
+
+type unixListener struct{ net.Listener }
+
+func NewUnixListener(addr string) (net.Listener, error) {
+	if err := os.Remove(addr); err != nil && !os.IsNotExist(err) {
+		return nil, err
+	}
+	l, err := net.Listen("unix", addr)
+	if err != nil {
+		return nil, err
+	}
+	return &unixListener{l}, nil
+}
+
+func (ul *unixListener) Close() error {
+	if err := os.Remove(ul.Addr().String()); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+	return ul.Listener.Close()
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/types/doc.go b/vendor/github.com/coreos/etcd/pkg/types/doc.go
new file mode 100644
index 0000000..de8ef0b
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/doc.go
@@ -0,0 +1,17 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package types declares various data types and implements type-checking
+// functions.
+package types
diff --git a/vendor/github.com/coreos/etcd/pkg/types/id.go b/vendor/github.com/coreos/etcd/pkg/types/id.go
new file mode 100644
index 0000000..1b042d9
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/id.go
@@ -0,0 +1,41 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package types
+
+import (
+	"strconv"
+)
+
+// ID represents a generic identifier which is canonically
+// stored as a uint64 but is typically represented as a
+// base-16 string for input/output
+type ID uint64
+
+func (i ID) String() string {
+	return strconv.FormatUint(uint64(i), 16)
+}
+
+// IDFromString attempts to create an ID from a base-16 string.
+func IDFromString(s string) (ID, error) {
+	i, err := strconv.ParseUint(s, 16, 64)
+	return ID(i), err
+}
+
+// IDSlice implements the sort interface
+type IDSlice []ID
+
+func (p IDSlice) Len() int           { return len(p) }
+func (p IDSlice) Less(i, j int) bool { return uint64(p[i]) < uint64(p[j]) }
+func (p IDSlice) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
diff --git a/vendor/github.com/coreos/etcd/pkg/types/set.go b/vendor/github.com/coreos/etcd/pkg/types/set.go
new file mode 100644
index 0000000..c111b0c
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/set.go
@@ -0,0 +1,178 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package types
+
+import (
+	"reflect"
+	"sort"
+	"sync"
+)
+
+type Set interface {
+	Add(string)
+	Remove(string)
+	Contains(string) bool
+	Equals(Set) bool
+	Length() int
+	Values() []string
+	Copy() Set
+	Sub(Set) Set
+}
+
+func NewUnsafeSet(values ...string) *unsafeSet {
+	set := &unsafeSet{make(map[string]struct{})}
+	for _, v := range values {
+		set.Add(v)
+	}
+	return set
+}
+
+func NewThreadsafeSet(values ...string) *tsafeSet {
+	us := NewUnsafeSet(values...)
+	return &tsafeSet{us, sync.RWMutex{}}
+}
+
+type unsafeSet struct {
+	d map[string]struct{}
+}
+
+// Add adds a new value to the set (no-op if the value is already present)
+func (us *unsafeSet) Add(value string) {
+	us.d[value] = struct{}{}
+}
+
+// Remove removes the given value from the set
+func (us *unsafeSet) Remove(value string) {
+	delete(us.d, value)
+}
+
+// Contains returns whether the set contains the given value
+func (us *unsafeSet) Contains(value string) (exists bool) {
+	_, exists = us.d[value]
+	return exists
+}
+
+// ContainsAll returns whether the set contains all given values
+func (us *unsafeSet) ContainsAll(values []string) bool {
+	for _, s := range values {
+		if !us.Contains(s) {
+			return false
+		}
+	}
+	return true
+}
+
+// Equals returns whether the contents of two sets are identical
+func (us *unsafeSet) Equals(other Set) bool {
+	v1 := sort.StringSlice(us.Values())
+	v2 := sort.StringSlice(other.Values())
+	v1.Sort()
+	v2.Sort()
+	return reflect.DeepEqual(v1, v2)
+}
+
+// Length returns the number of elements in the set
+func (us *unsafeSet) Length() int {
+	return len(us.d)
+}
+
+// Values returns the values of the Set in an unspecified order.
+func (us *unsafeSet) Values() (values []string) {
+	values = make([]string, 0)
+	for val := range us.d {
+		values = append(values, val)
+	}
+	return values
+}
+
+// Copy creates a new Set containing the values of the first
+func (us *unsafeSet) Copy() Set {
+	cp := NewUnsafeSet()
+	for val := range us.d {
+		cp.Add(val)
+	}
+
+	return cp
+}
+
+// Sub removes all elements in other from the set
+func (us *unsafeSet) Sub(other Set) Set {
+	oValues := other.Values()
+	result := us.Copy().(*unsafeSet)
+
+	for _, val := range oValues {
+		if _, ok := result.d[val]; !ok {
+			continue
+		}
+		delete(result.d, val)
+	}
+
+	return result
+}
+
+type tsafeSet struct {
+	us *unsafeSet
+	m  sync.RWMutex
+}
+
+func (ts *tsafeSet) Add(value string) {
+	ts.m.Lock()
+	defer ts.m.Unlock()
+	ts.us.Add(value)
+}
+
+func (ts *tsafeSet) Remove(value string) {
+	ts.m.Lock()
+	defer ts.m.Unlock()
+	ts.us.Remove(value)
+}
+
+func (ts *tsafeSet) Contains(value string) (exists bool) {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	return ts.us.Contains(value)
+}
+
+func (ts *tsafeSet) Equals(other Set) bool {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	return ts.us.Equals(other)
+}
+
+func (ts *tsafeSet) Length() int {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	return ts.us.Length()
+}
+
+func (ts *tsafeSet) Values() (values []string) {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	return ts.us.Values()
+}
+
+func (ts *tsafeSet) Copy() Set {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	usResult := ts.us.Copy().(*unsafeSet)
+	return &tsafeSet{usResult, sync.RWMutex{}}
+}
+
+func (ts *tsafeSet) Sub(other Set) Set {
+	ts.m.RLock()
+	defer ts.m.RUnlock()
+	usResult := ts.us.Sub(other).(*unsafeSet)
+	return &tsafeSet{usResult, sync.RWMutex{}}
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/types/slice.go b/vendor/github.com/coreos/etcd/pkg/types/slice.go
new file mode 100644
index 0000000..0dd9ca7
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/slice.go
@@ -0,0 +1,22 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package types
+
+// Uint64Slice implements sort interface
+type Uint64Slice []uint64
+
+func (p Uint64Slice) Len() int           { return len(p) }
+func (p Uint64Slice) Less(i, j int) bool { return p[i] < p[j] }
+func (p Uint64Slice) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
diff --git a/vendor/github.com/coreos/etcd/pkg/types/urls.go b/vendor/github.com/coreos/etcd/pkg/types/urls.go
new file mode 100644
index 0000000..9e5d03f
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/urls.go
@@ -0,0 +1,82 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package types
+
+import (
+	"errors"
+	"fmt"
+	"net"
+	"net/url"
+	"sort"
+	"strings"
+)
+
+type URLs []url.URL
+
+func NewURLs(strs []string) (URLs, error) {
+	all := make([]url.URL, len(strs))
+	if len(all) == 0 {
+		return nil, errors.New("no valid URLs given")
+	}
+	for i, in := range strs {
+		in = strings.TrimSpace(in)
+		u, err := url.Parse(in)
+		if err != nil {
+			return nil, err
+		}
+		if u.Scheme != "http" && u.Scheme != "https" && u.Scheme != "unix" && u.Scheme != "unixs" {
+			return nil, fmt.Errorf("URL scheme must be http, https, unix, or unixs: %s", in)
+		}
+		if _, _, err := net.SplitHostPort(u.Host); err != nil {
+			return nil, fmt.Errorf(`URL address does not have the form "host:port": %s`, in)
+		}
+		if u.Path != "" {
+			return nil, fmt.Errorf("URL must not contain a path: %s", in)
+		}
+		all[i] = *u
+	}
+	us := URLs(all)
+	us.Sort()
+
+	return us, nil
+}
+
+func MustNewURLs(strs []string) URLs {
+	urls, err := NewURLs(strs)
+	if err != nil {
+		panic(err)
+	}
+	return urls
+}
+
+func (us URLs) String() string {
+	return strings.Join(us.StringSlice(), ",")
+}
+
+func (us *URLs) Sort() {
+	sort.Sort(us)
+}
+func (us URLs) Len() int           { return len(us) }
+func (us URLs) Less(i, j int) bool { return us[i].String() < us[j].String() }
+func (us URLs) Swap(i, j int)      { us[i], us[j] = us[j], us[i] }
+
+func (us URLs) StringSlice() []string {
+	out := make([]string, len(us))
+	for i := range us {
+		out[i] = us[i].String()
+	}
+
+	return out
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/types/urlsmap.go b/vendor/github.com/coreos/etcd/pkg/types/urlsmap.go
new file mode 100644
index 0000000..47690cc
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/types/urlsmap.go
@@ -0,0 +1,107 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package types
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// URLsMap is a map from a name to its URLs.
+type URLsMap map[string]URLs
+
+// NewURLsMap returns a URLsMap instantiated from the given string,
+// which consists of discovery-formatted names-to-URLs, like:
+// mach0=http://1.1.1.1:2380,mach0=http://2.2.2.2::2380,mach1=http://3.3.3.3:2380,mach2=http://4.4.4.4:2380
+func NewURLsMap(s string) (URLsMap, error) {
+	m := parse(s)
+
+	cl := URLsMap{}
+	for name, urls := range m {
+		us, err := NewURLs(urls)
+		if err != nil {
+			return nil, err
+		}
+		cl[name] = us
+	}
+	return cl, nil
+}
+
+// NewURLsMapFromStringMap takes a map of strings and returns a URLsMap. The
+// string values in the map can be multiple values separated by the sep string.
+func NewURLsMapFromStringMap(m map[string]string, sep string) (URLsMap, error) {
+	var err error
+	um := URLsMap{}
+	for k, v := range m {
+		um[k], err = NewURLs(strings.Split(v, sep))
+		if err != nil {
+			return nil, err
+		}
+	}
+	return um, nil
+}
+
+// String turns URLsMap into discovery-formatted name-to-URLs sorted by name.
+func (c URLsMap) String() string {
+	var pairs []string
+	for name, urls := range c {
+		for _, url := range urls {
+			pairs = append(pairs, fmt.Sprintf("%s=%s", name, url.String()))
+		}
+	}
+	sort.Strings(pairs)
+	return strings.Join(pairs, ",")
+}
+
+// URLs returns a list of all URLs.
+// The returned list is sorted in ascending lexicographical order.
+func (c URLsMap) URLs() []string {
+	var urls []string
+	for _, us := range c {
+		for _, u := range us {
+			urls = append(urls, u.String())
+		}
+	}
+	sort.Strings(urls)
+	return urls
+}
+
+// Len returns the size of URLsMap.
+func (c URLsMap) Len() int {
+	return len(c)
+}
+
+// parse parses the given string and returns a map listing the values specified for each key.
+func parse(s string) map[string][]string {
+	m := make(map[string][]string)
+	for s != "" {
+		key := s
+		if i := strings.IndexAny(key, ","); i >= 0 {
+			key, s = key[:i], key[i+1:]
+		} else {
+			s = ""
+		}
+		if key == "" {
+			continue
+		}
+		value := ""
+		if i := strings.Index(key, "="); i >= 0 {
+			key, value = key[:i], key[i+1:]
+		}
+		m[key] = append(m[key], value)
+	}
+	return m
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/wait/wait.go b/vendor/github.com/coreos/etcd/pkg/wait/wait.go
new file mode 100644
index 0000000..9b1df41
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/wait/wait.go
@@ -0,0 +1,91 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package wait provides utility functions for polling, listening using Go
+// channel.
+package wait
+
+import (
+	"log"
+	"sync"
+)
+
+// Wait is an interface that provides the ability to wait and trigger events that
+// are associated with IDs.
+type Wait interface {
+	// Register waits returns a chan that waits on the given ID.
+	// The chan will be triggered when Trigger is called with
+	// the same ID.
+	Register(id uint64) <-chan interface{}
+	// Trigger triggers the waiting chans with the given ID.
+	Trigger(id uint64, x interface{})
+	IsRegistered(id uint64) bool
+}
+
+type list struct {
+	l sync.RWMutex
+	m map[uint64]chan interface{}
+}
+
+// New creates a Wait.
+func New() Wait {
+	return &list{m: make(map[uint64]chan interface{})}
+}
+
+func (w *list) Register(id uint64) <-chan interface{} {
+	w.l.Lock()
+	defer w.l.Unlock()
+	ch := w.m[id]
+	if ch == nil {
+		ch = make(chan interface{}, 1)
+		w.m[id] = ch
+	} else {
+		log.Panicf("dup id %x", id)
+	}
+	return ch
+}
+
+func (w *list) Trigger(id uint64, x interface{}) {
+	w.l.Lock()
+	ch := w.m[id]
+	delete(w.m, id)
+	w.l.Unlock()
+	if ch != nil {
+		ch <- x
+		close(ch)
+	}
+}
+
+func (w *list) IsRegistered(id uint64) bool {
+	w.l.RLock()
+	defer w.l.RUnlock()
+	_, ok := w.m[id]
+	return ok
+}
+
+type waitWithResponse struct {
+	ch <-chan interface{}
+}
+
+func NewWithResponse(ch <-chan interface{}) Wait {
+	return &waitWithResponse{ch: ch}
+}
+
+func (w *waitWithResponse) Register(id uint64) <-chan interface{} {
+	return w.ch
+}
+func (w *waitWithResponse) Trigger(id uint64, x interface{}) {}
+func (w *waitWithResponse) IsRegistered(id uint64) bool {
+	panic("waitWithResponse.IsRegistered() shouldn't be called")
+}
diff --git a/vendor/github.com/coreos/etcd/pkg/wait/wait_time.go b/vendor/github.com/coreos/etcd/pkg/wait/wait_time.go
new file mode 100644
index 0000000..297e48a
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/wait/wait_time.go
@@ -0,0 +1,66 @@
+// Copyright 2015 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package wait
+
+import "sync"
+
+type WaitTime interface {
+	// Wait returns a chan that waits on the given logical deadline.
+	// The chan will be triggered when Trigger is called with a
+	// deadline that is later than the one it is waiting for.
+	Wait(deadline uint64) <-chan struct{}
+	// Trigger triggers all the waiting chans with an earlier logical deadline.
+	Trigger(deadline uint64)
+}
+
+var closec chan struct{}
+
+func init() { closec = make(chan struct{}); close(closec) }
+
+type timeList struct {
+	l                   sync.Mutex
+	lastTriggerDeadline uint64
+	m                   map[uint64]chan struct{}
+}
+
+func NewTimeList() *timeList {
+	return &timeList{m: make(map[uint64]chan struct{})}
+}
+
+func (tl *timeList) Wait(deadline uint64) <-chan struct{} {
+	tl.l.Lock()
+	defer tl.l.Unlock()
+	if tl.lastTriggerDeadline >= deadline {
+		return closec
+	}
+	ch := tl.m[deadline]
+	if ch == nil {
+		ch = make(chan struct{})
+		tl.m[deadline] = ch
+	}
+	return ch
+}
+
+func (tl *timeList) Trigger(deadline uint64) {
+	tl.l.Lock()
+	defer tl.l.Unlock()
+	tl.lastTriggerDeadline = deadline
+	for t, ch := range tl.m {
+		if t <= deadline {
+			delete(tl.m, t)
+			close(ch)
+		}
+	}
+}