Copy dependencies into vendor dir, using dep

2018-04-27 14:34:48 +01:00
1 parent 549ccff5eb
commit b534ea60f5
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Microsoft Corporation
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
@@ -0,0 +1,12 @@
+# go-ansiterm
+
+This is a cross platform Ansi Terminal Emulation library.  It reads a stream of Ansi characters and produces the appropriate function calls.  The results of the function calls are platform dependent.
+
+For example the parser might receive "ESC, [, A" as a stream of three characters.  This is the code for Cursor Up (http://www.vt100.net/docs/vt510-rm/CUU).  The parser then calls the cursor up function (CUU()) on an event handler.  The event handler determines what platform specific work must be done to cause the cursor to move up one position.
+
+The parser (parser.go) is a partial implementation of this state machine (http://vt100.net/emu/vt500_parser.png).  There are also two event handler implementations, one for tests (test_event_handler.go) to validate that the expected events are being produced and called, the other is a Windows implementation (winterm/win_event_handler.go).
+
+See parser_test.go for examples exercising the state machine and generating appropriate function calls.
+
+-----
+This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional questions or comments.
@@ -0,0 +1,188 @@
+package ansiterm
+
+const LogEnv = "DEBUG_TERMINAL"
+
+// ANSI constants
+// References:
+// -- http://www.ecma-international.org/publications/standards/Ecma-048.htm
+// -- http://man7.org/linux/man-pages/man4/console_codes.4.html
+// -- http://manpages.ubuntu.com/manpages/intrepid/man4/console_codes.4.html
+// -- http://en.wikipedia.org/wiki/ANSI_escape_code
+// -- http://vt100.net/emu/dec_ansi_parser
+// -- http://vt100.net/emu/vt500_parser.svg
+// -- http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
+// -- http://www.inwap.com/pdp10/ansicode.txt
+const (
+	// ECMA-48 Set Graphics Rendition
+	// Note:
+	// -- Constants leading with an underscore (e.g., _ANSI_xxx) are unsupported or reserved
+	// -- Fonts could possibly be supported via SetCurrentConsoleFontEx
+	// -- Windows does not expose the per-window cursor (i.e., caret) blink times
+	ANSI_SGR_RESET              = 0
+	ANSI_SGR_BOLD               = 1
+	ANSI_SGR_DIM                = 2
+	_ANSI_SGR_ITALIC            = 3
+	ANSI_SGR_UNDERLINE          = 4
+	_ANSI_SGR_BLINKSLOW         = 5
+	_ANSI_SGR_BLINKFAST         = 6
+	ANSI_SGR_REVERSE            = 7
+	_ANSI_SGR_INVISIBLE         = 8
+	_ANSI_SGR_LINETHROUGH       = 9
+	_ANSI_SGR_FONT_00           = 10
+	_ANSI_SGR_FONT_01           = 11
+	_ANSI_SGR_FONT_02           = 12
+	_ANSI_SGR_FONT_03           = 13
+	_ANSI_SGR_FONT_04           = 14
+	_ANSI_SGR_FONT_05           = 15
+	_ANSI_SGR_FONT_06           = 16
+	_ANSI_SGR_FONT_07           = 17
+	_ANSI_SGR_FONT_08           = 18
+	_ANSI_SGR_FONT_09           = 19
+	_ANSI_SGR_FONT_10           = 20
+	_ANSI_SGR_DOUBLEUNDERLINE   = 21
+	ANSI_SGR_BOLD_DIM_OFF       = 22
+	_ANSI_SGR_ITALIC_OFF        = 23
+	ANSI_SGR_UNDERLINE_OFF      = 24
+	_ANSI_SGR_BLINK_OFF         = 25
+	_ANSI_SGR_RESERVED_00       = 26
+	ANSI_SGR_REVERSE_OFF        = 27
+	_ANSI_SGR_INVISIBLE_OFF     = 28
+	_ANSI_SGR_LINETHROUGH_OFF   = 29
+	ANSI_SGR_FOREGROUND_BLACK   = 30
+	ANSI_SGR_FOREGROUND_RED     = 31
+	ANSI_SGR_FOREGROUND_GREEN   = 32
+	ANSI_SGR_FOREGROUND_YELLOW  = 33
+	ANSI_SGR_FOREGROUND_BLUE    = 34
+	ANSI_SGR_FOREGROUND_MAGENTA = 35
+	ANSI_SGR_FOREGROUND_CYAN    = 36
+	ANSI_SGR_FOREGROUND_WHITE   = 37
+	_ANSI_SGR_RESERVED_01       = 38
+	ANSI_SGR_FOREGROUND_DEFAULT = 39
+	ANSI_SGR_BACKGROUND_BLACK   = 40
+	ANSI_SGR_BACKGROUND_RED     = 41
+	ANSI_SGR_BACKGROUND_GREEN   = 42
+	ANSI_SGR_BACKGROUND_YELLOW  = 43
+	ANSI_SGR_BACKGROUND_BLUE    = 44
+	ANSI_SGR_BACKGROUND_MAGENTA = 45
+	ANSI_SGR_BACKGROUND_CYAN    = 46
+	ANSI_SGR_BACKGROUND_WHITE   = 47
+	_ANSI_SGR_RESERVED_02       = 48
+	ANSI_SGR_BACKGROUND_DEFAULT = 49
+	// 50 - 65: Unsupported
+
+	ANSI_MAX_CMD_LENGTH = 4096
+
+	MAX_INPUT_EVENTS = 128
+	DEFAULT_WIDTH    = 80
+	DEFAULT_HEIGHT   = 24
+
+	ANSI_BEL              = 0x07
+	ANSI_BACKSPACE        = 0x08
+	ANSI_TAB              = 0x09
+	ANSI_LINE_FEED        = 0x0A
+	ANSI_VERTICAL_TAB     = 0x0B
+	ANSI_FORM_FEED        = 0x0C
+	ANSI_CARRIAGE_RETURN  = 0x0D
+	ANSI_ESCAPE_PRIMARY   = 0x1B
+	ANSI_ESCAPE_SECONDARY = 0x5B
+	ANSI_OSC_STRING_ENTRY = 0x5D
+	ANSI_COMMAND_FIRST    = 0x40
+	ANSI_COMMAND_LAST     = 0x7E
+	DCS_ENTRY             = 0x90
+	CSI_ENTRY             = 0x9B
+	OSC_STRING            = 0x9D
+	ANSI_PARAMETER_SEP    = ";"
+	ANSI_CMD_G0           = '('
+	ANSI_CMD_G1           = ')'
+	ANSI_CMD_G2           = '*'
+	ANSI_CMD_G3           = '+'
+	ANSI_CMD_DECPNM       = '>'
+	ANSI_CMD_DECPAM       = '='
+	ANSI_CMD_OSC          = ']'
+	ANSI_CMD_STR_TERM     = '\\'
+
+	KEY_CONTROL_PARAM_2 = ";2"
+	KEY_CONTROL_PARAM_3 = ";3"
+	KEY_CONTROL_PARAM_4 = ";4"
+	KEY_CONTROL_PARAM_5 = ";5"
+	KEY_CONTROL_PARAM_6 = ";6"
+	KEY_CONTROL_PARAM_7 = ";7"
+	KEY_CONTROL_PARAM_8 = ";8"
+	KEY_ESC_CSI         = "\x1B["
+	KEY_ESC_N           = "\x1BN"
+	KEY_ESC_O           = "\x1BO"
+
+	FILL_CHARACTER = ' '
+)
+
+func getByteRange(start byte, end byte) []byte {
+	bytes := make([]byte, 0, 32)
+	for i := start; i <= end; i++ {
+		bytes = append(bytes, byte(i))
+	}
+
+	return bytes
+}
+
+var toGroundBytes = getToGroundBytes()
+var executors = getExecuteBytes()
+
+// SPACE		  20+A0 hex  Always and everywhere a blank space
+// Intermediate	  20-2F hex   !"#$%&'()*+,-./
+var intermeds = getByteRange(0x20, 0x2F)
+
+// Parameters	  30-3F hex  0123456789:;<=>?
+// CSI Parameters 30-39, 3B hex 0123456789;
+var csiParams = getByteRange(0x30, 0x3F)
+
+var csiCollectables = append(getByteRange(0x30, 0x39), getByteRange(0x3B, 0x3F)...)
+
+// Uppercase	  40-5F hex  @ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_
+var upperCase = getByteRange(0x40, 0x5F)
+
+// Lowercase	  60-7E hex  `abcdefghijlkmnopqrstuvwxyz{|}~
+var lowerCase = getByteRange(0x60, 0x7E)
+
+// Alphabetics	  40-7E hex  (all of upper and lower case)
+var alphabetics = append(upperCase, lowerCase...)
+
+var printables = getByteRange(0x20, 0x7F)
+
+var escapeIntermediateToGroundBytes = getByteRange(0x30, 0x7E)
+var escapeToGroundBytes = getEscapeToGroundBytes()
+
+// See http://www.vt100.net/emu/vt500_parser.png for description of the complex
+// byte ranges below
+
+func getEscapeToGroundBytes() []byte {
+	escapeToGroundBytes := getByteRange(0x30, 0x4F)
+	escapeToGroundBytes = append(escapeToGroundBytes, getByteRange(0x51, 0x57)...)
+	escapeToGroundBytes = append(escapeToGroundBytes, 0x59)
+	escapeToGroundBytes = append(escapeToGroundBytes, 0x5A)
+	escapeToGroundBytes = append(escapeToGroundBytes, 0x5C)
+	escapeToGroundBytes = append(escapeToGroundBytes, getByteRange(0x60, 0x7E)...)
+	return escapeToGroundBytes
+}
+
+func getExecuteBytes() []byte {
+	executeBytes := getByteRange(0x00, 0x17)
+	executeBytes = append(executeBytes, 0x19)
+	executeBytes = append(executeBytes, getByteRange(0x1C, 0x1F)...)
+	return executeBytes
+}
+
+func getToGroundBytes() []byte {
+	groundBytes := []byte{0x18}
+	groundBytes = append(groundBytes, 0x1A)
+	groundBytes = append(groundBytes, getByteRange(0x80, 0x8F)...)
+	groundBytes = append(groundBytes, getByteRange(0x91, 0x97)...)
+	groundBytes = append(groundBytes, 0x99)
+	groundBytes = append(groundBytes, 0x9A)
+	groundBytes = append(groundBytes, 0x9C)
+	return groundBytes
+}
+
+// Delete		     7F hex  Always and everywhere ignored
+// C1 Control	  80-9F hex  32 additional control characters
+// G1 Displayable A1-FE hex  94 additional displayable characters
+// Special		  A0+FF hex  Same as SPACE and DELETE
@@ -0,0 +1,7 @@
+package ansiterm
+
+type ansiContext struct {
+	currentChar byte
+	paramBuffer []byte
+	interBuffer []byte
+}
@@ -0,0 +1,49 @@
+package ansiterm
+
+type csiEntryState struct {
+	baseState
+}
+
+func (csiState csiEntryState) Handle(b byte) (s state, e error) {
+	csiState.parser.logf("CsiEntry::Handle %#x", b)
+
+	nextState, err := csiState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case sliceContains(alphabetics, b):
+		return csiState.parser.ground, nil
+	case sliceContains(csiCollectables, b):
+		return csiState.parser.csiParam, nil
+	case sliceContains(executors, b):
+		return csiState, csiState.parser.execute()
+	}
+
+	return csiState, nil
+}
+
+func (csiState csiEntryState) Transition(s state) error {
+	csiState.parser.logf("CsiEntry::Transition %s --> %s", csiState.Name(), s.Name())
+	csiState.baseState.Transition(s)
+
+	switch s {
+	case csiState.parser.ground:
+		return csiState.parser.csiDispatch()
+	case csiState.parser.csiParam:
+		switch {
+		case sliceContains(csiParams, csiState.parser.context.currentChar):
+			csiState.parser.collectParam()
+		case sliceContains(intermeds, csiState.parser.context.currentChar):
+			csiState.parser.collectInter()
+		}
+	}
+
+	return nil
+}
+
+func (csiState csiEntryState) Enter() error {
+	csiState.parser.clear()
+	return nil
+}
@@ -0,0 +1,38 @@
+package ansiterm
+
+type csiParamState struct {
+	baseState
+}
+
+func (csiState csiParamState) Handle(b byte) (s state, e error) {
+	csiState.parser.logf("CsiParam::Handle %#x", b)
+
+	nextState, err := csiState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case sliceContains(alphabetics, b):
+		return csiState.parser.ground, nil
+	case sliceContains(csiCollectables, b):
+		csiState.parser.collectParam()
+		return csiState, nil
+	case sliceContains(executors, b):
+		return csiState, csiState.parser.execute()
+	}
+
+	return csiState, nil
+}
+
+func (csiState csiParamState) Transition(s state) error {
+	csiState.parser.logf("CsiParam::Transition %s --> %s", csiState.Name(), s.Name())
+	csiState.baseState.Transition(s)
+
+	switch s {
+	case csiState.parser.ground:
+		return csiState.parser.csiDispatch()
+	}
+
+	return nil
+}
@@ -0,0 +1,36 @@
+package ansiterm
+
+type escapeIntermediateState struct {
+	baseState
+}
+
+func (escState escapeIntermediateState) Handle(b byte) (s state, e error) {
+	escState.parser.logf("escapeIntermediateState::Handle %#x", b)
+	nextState, err := escState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case sliceContains(intermeds, b):
+		return escState, escState.parser.collectInter()
+	case sliceContains(executors, b):
+		return escState, escState.parser.execute()
+	case sliceContains(escapeIntermediateToGroundBytes, b):
+		return escState.parser.ground, nil
+	}
+
+	return escState, nil
+}
+
+func (escState escapeIntermediateState) Transition(s state) error {
+	escState.parser.logf("escapeIntermediateState::Transition %s --> %s", escState.Name(), s.Name())
+	escState.baseState.Transition(s)
+
+	switch s {
+	case escState.parser.ground:
+		return escState.parser.escDispatch()
+	}
+
+	return nil
+}
@@ -0,0 +1,47 @@
+package ansiterm
+
+type escapeState struct {
+	baseState
+}
+
+func (escState escapeState) Handle(b byte) (s state, e error) {
+	escState.parser.logf("escapeState::Handle %#x", b)
+	nextState, err := escState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case b == ANSI_ESCAPE_SECONDARY:
+		return escState.parser.csiEntry, nil
+	case b == ANSI_OSC_STRING_ENTRY:
+		return escState.parser.oscString, nil
+	case sliceContains(executors, b):
+		return escState, escState.parser.execute()
+	case sliceContains(escapeToGroundBytes, b):
+		return escState.parser.ground, nil
+	case sliceContains(intermeds, b):
+		return escState.parser.escapeIntermediate, nil
+	}
+
+	return escState, nil
+}
+
+func (escState escapeState) Transition(s state) error {
+	escState.parser.logf("Escape::Transition %s --> %s", escState.Name(), s.Name())
+	escState.baseState.Transition(s)
+
+	switch s {
+	case escState.parser.ground:
+		return escState.parser.escDispatch()
+	case escState.parser.escapeIntermediate:
+		return escState.parser.collectInter()
+	}
+
+	return nil
+}
+
+func (escState escapeState) Enter() error {
+	escState.parser.clear()
+	return nil
+}
@@ -0,0 +1,90 @@
+package ansiterm
+
+type AnsiEventHandler interface {
+	// Print
+	Print(b byte) error
+
+	// Execute C0 commands
+	Execute(b byte) error
+
+	// CUrsor Up
+	CUU(int) error
+
+	// CUrsor Down
+	CUD(int) error
+
+	// CUrsor Forward
+	CUF(int) error
+
+	// CUrsor Backward
+	CUB(int) error
+
+	// Cursor to Next Line
+	CNL(int) error
+
+	// Cursor to Previous Line
+	CPL(int) error
+
+	// Cursor Horizontal position Absolute
+	CHA(int) error
+
+	// Vertical line Position Absolute
+	VPA(int) error
+
+	// CUrsor Position
+	CUP(int, int) error
+
+	// Horizontal and Vertical Position (depends on PUM)
+	HVP(int, int) error
+
+	// Text Cursor Enable Mode
+	DECTCEM(bool) error
+
+	// Origin Mode
+	DECOM(bool) error
+
+	// 132 Column Mode
+	DECCOLM(bool) error
+
+	// Erase in Display
+	ED(int) error
+
+	// Erase in Line
+	EL(int) error
+
+	// Insert Line
+	IL(int) error
+
+	// Delete Line
+	DL(int) error
+
+	// Insert Character
+	ICH(int) error
+
+	// Delete Character
+	DCH(int) error
+
+	// Set Graphics Rendition
+	SGR([]int) error
+
+	// Pan Down
+	SU(int) error
+
+	// Pan Up
+	SD(int) error
+
+	// Device Attributes
+	DA([]string) error
+
+	// Set Top and Bottom Margins
+	DECSTBM(int, int) error
+
+	// Index
+	IND() error
+
+	// Reverse Index
+	RI() error
+
+	// Flush updates from previous commands
+	Flush() error
+}
@@ -0,0 +1,24 @@
+package ansiterm
+
+type groundState struct {
+	baseState
+}
+
+func (gs groundState) Handle(b byte) (s state, e error) {
+	gs.parser.context.currentChar = b
+
+	nextState, err := gs.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case sliceContains(printables, b):
+		return gs, gs.parser.print()
+
+	case sliceContains(executors, b):
+		return gs, gs.parser.execute()
+	}
+
+	return gs, nil
+}
@@ -0,0 +1,31 @@
+package ansiterm
+
+type oscStringState struct {
+	baseState
+}
+
+func (oscState oscStringState) Handle(b byte) (s state, e error) {
+	oscState.parser.logf("OscString::Handle %#x", b)
+	nextState, err := oscState.baseState.Handle(b)
+	if nextState != nil || err != nil {
+		return nextState, err
+	}
+
+	switch {
+	case isOscStringTerminator(b):
+		return oscState.parser.ground, nil
+	}
+
+	return oscState, nil
+}
+
+// See below for OSC string terminators for linux
+// http://man7.org/linux/man-pages/man4/console_codes.4.html
+func isOscStringTerminator(b byte) bool {
+
+	if b == ANSI_BEL || b == 0x5C {
+		return true
+	}
+
+	return false
+}
@@ -0,0 +1,151 @@
+package ansiterm
+
+import (
+	"errors"
+	"log"
+	"os"
+)
+
+type AnsiParser struct {
+	currState          state
+	eventHandler       AnsiEventHandler
+	context            *ansiContext
+	csiEntry           state
+	csiParam           state
+	dcsEntry           state
+	escape             state
+	escapeIntermediate state
+	error              state
+	ground             state
+	oscString          state
+	stateMap           []state
+
+	logf func(string, ...interface{})
+}
+
+type Option func(*AnsiParser)
+
+func WithLogf(f func(string, ...interface{})) Option {
+	return func(ap *AnsiParser) {
+		ap.logf = f
+	}
+}
+
+func CreateParser(initialState string, evtHandler AnsiEventHandler, opts ...Option) *AnsiParser {
+	ap := &AnsiParser{
+		eventHandler: evtHandler,
+		context:      &ansiContext{},
+	}
+	for _, o := range opts {
+		o(ap)
+	}
+
+	if isDebugEnv := os.Getenv(LogEnv); isDebugEnv == "1" {
+		logFile, _ := os.Create("ansiParser.log")
+		logger := log.New(logFile, "", log.LstdFlags)
+		if ap.logf != nil {
+			l := ap.logf
+			ap.logf = func(s string, v ...interface{}) {
+				l(s, v...)
+				logger.Printf(s, v...)
+			}
+		} else {
+			ap.logf = logger.Printf
+		}
+	}
+
+	if ap.logf == nil {
+		ap.logf = func(string, ...interface{}) {}
+	}
+
+	ap.csiEntry = csiEntryState{baseState{name: "CsiEntry", parser: ap}}
+	ap.csiParam = csiParamState{baseState{name: "CsiParam", parser: ap}}
+	ap.dcsEntry = dcsEntryState{baseState{name: "DcsEntry", parser: ap}}
+	ap.escape = escapeState{baseState{name: "Escape", parser: ap}}
+	ap.escapeIntermediate = escapeIntermediateState{baseState{name: "EscapeIntermediate", parser: ap}}
+	ap.error = errorState{baseState{name: "Error", parser: ap}}
+	ap.ground = groundState{baseState{name: "Ground", parser: ap}}
+	ap.oscString = oscStringState{baseState{name: "OscString", parser: ap}}
+
+	ap.stateMap = []state{
+		ap.csiEntry,
+		ap.csiParam,
+		ap.dcsEntry,
+		ap.escape,
+		ap.escapeIntermediate,
+		ap.error,
+		ap.ground,
+		ap.oscString,
+	}
+
+	ap.currState = getState(initialState, ap.stateMap)
+
+	ap.logf("CreateParser: parser %p", ap)
+	return ap
+}
+
+func getState(name string, states []state) state {
+	for _, el := range states {
+		if el.Name() == name {
+			return el
+		}
+	}
+
+	return nil
+}
+
+func (ap *AnsiParser) Parse(bytes []byte) (int, error) {
+	for i, b := range bytes {
+		if err := ap.handle(b); err != nil {
+			return i, err
+		}
+	}
+
+	return len(bytes), ap.eventHandler.Flush()
+}
+
+func (ap *AnsiParser) handle(b byte) error {
+	ap.context.currentChar = b
+	newState, err := ap.currState.Handle(b)
+	if err != nil {
+		return err
+	}
+
+	if newState == nil {
+		ap.logf("WARNING: newState is nil")
+		return errors.New("New state of 'nil' is invalid.")
+	}
+
+	if newState != ap.currState {
+		if err := ap.changeState(newState); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (ap *AnsiParser) changeState(newState state) error {
+	ap.logf("ChangeState %s --> %s", ap.currState.Name(), newState.Name())
+
+	// Exit old state
+	if err := ap.currState.Exit(); err != nil {
+		ap.logf("Exit state '%s' failed with : '%v'", ap.currState.Name(), err)
+		return err
+	}
+
+	// Perform transition action
+	if err := ap.currState.Transition(newState); err != nil {
+		ap.logf("Transition from '%s' to '%s' failed with: '%v'", ap.currState.Name(), newState.Name, err)
+		return err
+	}
+
+	// Enter new state
+	if err := newState.Enter(); err != nil {
+		ap.logf("Enter state '%s' failed with: '%v'", newState.Name(), err)
+		return err
+	}
+
+	ap.currState = newState
+	return nil
+}
@@ -0,0 +1,99 @@
+package ansiterm
+
+import (
+	"strconv"
+)
+
+func parseParams(bytes []byte) ([]string, error) {
+	paramBuff := make([]byte, 0, 0)
+	params := []string{}
+
+	for _, v := range bytes {
+		if v == ';' {
+			if len(paramBuff) > 0 {
+				// Completed parameter, append it to the list
+				s := string(paramBuff)
+				params = append(params, s)
+				paramBuff = make([]byte, 0, 0)
+			}
+		} else {
+			paramBuff = append(paramBuff, v)
+		}
+	}
+
+	// Last parameter may not be terminated with ';'
+	if len(paramBuff) > 0 {
+		s := string(paramBuff)
+		params = append(params, s)
+	}
+
+	return params, nil
+}
+
+func parseCmd(context ansiContext) (string, error) {
+	return string(context.currentChar), nil
+}
+
+func getInt(params []string, dflt int) int {
+	i := getInts(params, 1, dflt)[0]
+	return i
+}
+
+func getInts(params []string, minCount int, dflt int) []int {
+	ints := []int{}
+
+	for _, v := range params {
+		i, _ := strconv.Atoi(v)
+		// Zero is mapped to the default value in VT100.
+		if i == 0 {
+			i = dflt
+		}
+		ints = append(ints, i)
+	}
+
+	if len(ints) < minCount {
+		remaining := minCount - len(ints)
+		for i := 0; i < remaining; i++ {
+			ints = append(ints, dflt)
+		}
+	}
+
+	return ints
+}
+
+func (ap *AnsiParser) modeDispatch(param string, set bool) error {
+	switch param {
+	case "?3":
+		return ap.eventHandler.DECCOLM(set)
+	case "?6":
+		return ap.eventHandler.DECOM(set)
+	case "?25":
+		return ap.eventHandler.DECTCEM(set)
+	}
+	return nil
+}
+
+func (ap *AnsiParser) hDispatch(params []string) error {
+	if len(params) == 1 {
+		return ap.modeDispatch(params[0], true)
+	}
+
+	return nil
+}
+
+func (ap *AnsiParser) lDispatch(params []string) error {
+	if len(params) == 1 {
+		return ap.modeDispatch(params[0], false)
+	}
+
+	return nil
+}
+
+func getEraseParam(params []string) int {
+	param := getInt(params, 0)
+	if param < 0 || 3 < param {
+		param = 0
+	}
+
+	return param
+}
@@ -0,0 +1,119 @@
+package ansiterm
+
+func (ap *AnsiParser) collectParam() error {
+	currChar := ap.context.currentChar
+	ap.logf("collectParam %#x", currChar)
+	ap.context.paramBuffer = append(ap.context.paramBuffer, currChar)
+	return nil
+}
+
+func (ap *AnsiParser) collectInter() error {
+	currChar := ap.context.currentChar
+	ap.logf("collectInter %#x", currChar)
+	ap.context.paramBuffer = append(ap.context.interBuffer, currChar)
+	return nil
+}
+
+func (ap *AnsiParser) escDispatch() error {
+	cmd, _ := parseCmd(*ap.context)
+	intermeds := ap.context.interBuffer
+	ap.logf("escDispatch currentChar: %#x", ap.context.currentChar)
+	ap.logf("escDispatch: %v(%v)", cmd, intermeds)
+
+	switch cmd {
+	case "D": // IND
+		return ap.eventHandler.IND()
+	case "E": // NEL, equivalent to CRLF
+		err := ap.eventHandler.Execute(ANSI_CARRIAGE_RETURN)
+		if err == nil {
+			err = ap.eventHandler.Execute(ANSI_LINE_FEED)
+		}
+		return err
+	case "M": // RI
+		return ap.eventHandler.RI()
+	}
+
+	return nil
+}
+
+func (ap *AnsiParser) csiDispatch() error {
+	cmd, _ := parseCmd(*ap.context)
+	params, _ := parseParams(ap.context.paramBuffer)
+	ap.logf("Parsed params: %v with length: %d", params, len(params))
+
+	ap.logf("csiDispatch: %v(%v)", cmd, params)
+
+	switch cmd {
+	case "@":
+		return ap.eventHandler.ICH(getInt(params, 1))
+	case "A":
+		return ap.eventHandler.CUU(getInt(params, 1))
+	case "B":
+		return ap.eventHandler.CUD(getInt(params, 1))
+	case "C":
+		return ap.eventHandler.CUF(getInt(params, 1))
+	case "D":
+		return ap.eventHandler.CUB(getInt(params, 1))
+	case "E":
+		return ap.eventHandler.CNL(getInt(params, 1))
+	case "F":
+		return ap.eventHandler.CPL(getInt(params, 1))
+	case "G":
+		return ap.eventHandler.CHA(getInt(params, 1))
+	case "H":
+		ints := getInts(params, 2, 1)
+		x, y := ints[0], ints[1]
+		return ap.eventHandler.CUP(x, y)
+	case "J":
+		param := getEraseParam(params)
+		return ap.eventHandler.ED(param)
+	case "K":
+		param := getEraseParam(params)
+		return ap.eventHandler.EL(param)
+	case "L":
+		return ap.eventHandler.IL(getInt(params, 1))
+	case "M":
+		return ap.eventHandler.DL(getInt(params, 1))
+	case "P":
+		return ap.eventHandler.DCH(getInt(params, 1))
+	case "S":
+		return ap.eventHandler.SU(getInt(params, 1))
+	case "T":
+		return ap.eventHandler.SD(getInt(params, 1))
+	case "c":
+		return ap.eventHandler.DA(params)
+	case "d":
+		return ap.eventHandler.VPA(getInt(params, 1))
+	case "f":
+		ints := getInts(params, 2, 1)
+		x, y := ints[0], ints[1]
+		return ap.eventHandler.HVP(x, y)
+	case "h":
+		return ap.hDispatch(params)
+	case "l":
+		return ap.lDispatch(params)
+	case "m":
+		return ap.eventHandler.SGR(getInts(params, 1, 0))
+	case "r":
+		ints := getInts(params, 2, 1)
+		top, bottom := ints[0], ints[1]
+		return ap.eventHandler.DECSTBM(top, bottom)
+	default:
+		ap.logf("ERROR: Unsupported CSI command: '%s', with full context:  %v", cmd, ap.context)
+		return nil
+	}
+
+}
+
+func (ap *AnsiParser) print() error {
+	return ap.eventHandler.Print(ap.context.currentChar)
+}
+
+func (ap *AnsiParser) clear() error {
+	ap.context = &ansiContext{}
+	return nil
+}
+
+func (ap *AnsiParser) execute() error {
+	return ap.eventHandler.Execute(ap.context.currentChar)
+}
@@ -0,0 +1,71 @@
+package ansiterm
+
+type stateID int
+
+type state interface {
+	Enter() error
+	Exit() error
+	Handle(byte) (state, error)
+	Name() string
+	Transition(state) error
+}
+
+type baseState struct {
+	name   string
+	parser *AnsiParser
+}
+
+func (base baseState) Enter() error {
+	return nil
+}
+
+func (base baseState) Exit() error {
+	return nil
+}
+
+func (base baseState) Handle(b byte) (s state, e error) {
+
+	switch {
+	case b == CSI_ENTRY:
+		return base.parser.csiEntry, nil
+	case b == DCS_ENTRY:
+		return base.parser.dcsEntry, nil
+	case b == ANSI_ESCAPE_PRIMARY:
+		return base.parser.escape, nil
+	case b == OSC_STRING:
+		return base.parser.oscString, nil
+	case sliceContains(toGroundBytes, b):
+		return base.parser.ground, nil
+	}
+
+	return nil, nil
+}
+
+func (base baseState) Name() string {
+	return base.name
+}
+
+func (base baseState) Transition(s state) error {
+	if s == base.parser.ground {
+		execBytes := []byte{0x18}
+		execBytes = append(execBytes, 0x1A)
+		execBytes = append(execBytes, getByteRange(0x80, 0x8F)...)
+		execBytes = append(execBytes, getByteRange(0x91, 0x97)...)
+		execBytes = append(execBytes, 0x99)
+		execBytes = append(execBytes, 0x9A)
+
+		if sliceContains(execBytes, base.parser.context.currentChar) {
+			return base.parser.execute()
+		}
+	}
+
+	return nil
+}
+
+type dcsEntryState struct {
+	baseState
+}
+
+type errorState struct {
+	baseState
+}
@@ -0,0 +1,21 @@
+package ansiterm
+
+import (
+	"strconv"
+)
+
+func sliceContains(bytes []byte, b byte) bool {
+	for _, v := range bytes {
+		if v == b {
+			return true
+		}
+	}
+
+	return false
+}
+
+func convertBytesToInteger(bytes []byte) int {
+	s := string(bytes)
+	i, _ := strconv.Atoi(s)
+	return i
+}
@@ -0,0 +1,182 @@
+// +build windows
+
+package winterm
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"github.com/Azure/go-ansiterm"
+)
+
+// Windows keyboard constants
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/dd375731(v=vs.85).aspx.
+const (
+	VK_PRIOR    = 0x21 // PAGE UP key
+	VK_NEXT     = 0x22 // PAGE DOWN key
+	VK_END      = 0x23 // END key
+	VK_HOME     = 0x24 // HOME key
+	VK_LEFT     = 0x25 // LEFT ARROW key
+	VK_UP       = 0x26 // UP ARROW key
+	VK_RIGHT    = 0x27 // RIGHT ARROW key
+	VK_DOWN     = 0x28 // DOWN ARROW key
+	VK_SELECT   = 0x29 // SELECT key
+	VK_PRINT    = 0x2A // PRINT key
+	VK_EXECUTE  = 0x2B // EXECUTE key
+	VK_SNAPSHOT = 0x2C // PRINT SCREEN key
+	VK_INSERT   = 0x2D // INS key
+	VK_DELETE   = 0x2E // DEL key
+	VK_HELP     = 0x2F // HELP key
+	VK_F1       = 0x70 // F1 key
+	VK_F2       = 0x71 // F2 key
+	VK_F3       = 0x72 // F3 key
+	VK_F4       = 0x73 // F4 key
+	VK_F5       = 0x74 // F5 key
+	VK_F6       = 0x75 // F6 key
+	VK_F7       = 0x76 // F7 key
+	VK_F8       = 0x77 // F8 key
+	VK_F9       = 0x78 // F9 key
+	VK_F10      = 0x79 // F10 key
+	VK_F11      = 0x7A // F11 key
+	VK_F12      = 0x7B // F12 key
+
+	RIGHT_ALT_PRESSED  = 0x0001
+	LEFT_ALT_PRESSED   = 0x0002
+	RIGHT_CTRL_PRESSED = 0x0004
+	LEFT_CTRL_PRESSED  = 0x0008
+	SHIFT_PRESSED      = 0x0010
+	NUMLOCK_ON         = 0x0020
+	SCROLLLOCK_ON      = 0x0040
+	CAPSLOCK_ON        = 0x0080
+	ENHANCED_KEY       = 0x0100
+)
+
+type ansiCommand struct {
+	CommandBytes []byte
+	Command      string
+	Parameters   []string
+	IsSpecial    bool
+}
+
+func newAnsiCommand(command []byte) *ansiCommand {
+
+	if isCharacterSelectionCmdChar(command[1]) {
+		// Is Character Set Selection commands
+		return &ansiCommand{
+			CommandBytes: command,
+			Command:      string(command),
+			IsSpecial:    true,
+		}
+	}
+
+	// last char is command character
+	lastCharIndex := len(command) - 1
+
+	ac := &ansiCommand{
+		CommandBytes: command,
+		Command:      string(command[lastCharIndex]),
+		IsSpecial:    false,
+	}
+
+	// more than a single escape
+	if lastCharIndex != 0 {
+		start := 1
+		// skip if double char escape sequence
+		if command[0] == ansiterm.ANSI_ESCAPE_PRIMARY && command[1] == ansiterm.ANSI_ESCAPE_SECONDARY {
+			start++
+		}
+		// convert this to GetNextParam method
+		ac.Parameters = strings.Split(string(command[start:lastCharIndex]), ansiterm.ANSI_PARAMETER_SEP)
+	}
+
+	return ac
+}
+
+func (ac *ansiCommand) paramAsSHORT(index int, defaultValue int16) int16 {
+	if index < 0 || index >= len(ac.Parameters) {
+		return defaultValue
+	}
+
+	param, err := strconv.ParseInt(ac.Parameters[index], 10, 16)
+	if err != nil {
+		return defaultValue
+	}
+
+	return int16(param)
+}
+
+func (ac *ansiCommand) String() string {
+	return fmt.Sprintf("0x%v \"%v\" (\"%v\")",
+		bytesToHex(ac.CommandBytes),
+		ac.Command,
+		strings.Join(ac.Parameters, "\",\""))
+}
+
+// isAnsiCommandChar returns true if the passed byte falls within the range of ANSI commands.
+// See http://manpages.ubuntu.com/manpages/intrepid/man4/console_codes.4.html.
+func isAnsiCommandChar(b byte) bool {
+	switch {
+	case ansiterm.ANSI_COMMAND_FIRST <= b && b <= ansiterm.ANSI_COMMAND_LAST && b != ansiterm.ANSI_ESCAPE_SECONDARY:
+		return true
+	case b == ansiterm.ANSI_CMD_G1 || b == ansiterm.ANSI_CMD_OSC || b == ansiterm.ANSI_CMD_DECPAM || b == ansiterm.ANSI_CMD_DECPNM:
+		// non-CSI escape sequence terminator
+		return true
+	case b == ansiterm.ANSI_CMD_STR_TERM || b == ansiterm.ANSI_BEL:
+		// String escape sequence terminator
+		return true
+	}
+	return false
+}
+
+func isXtermOscSequence(command []byte, current byte) bool {
+	return (len(command) >= 2 && command[0] == ansiterm.ANSI_ESCAPE_PRIMARY && command[1] == ansiterm.ANSI_CMD_OSC && current != ansiterm.ANSI_BEL)
+}
+
+func isCharacterSelectionCmdChar(b byte) bool {
+	return (b == ansiterm.ANSI_CMD_G0 || b == ansiterm.ANSI_CMD_G1 || b == ansiterm.ANSI_CMD_G2 || b == ansiterm.ANSI_CMD_G3)
+}
+
+// bytesToHex converts a slice of bytes to a human-readable string.
+func bytesToHex(b []byte) string {
+	hex := make([]string, len(b))
+	for i, ch := range b {
+		hex[i] = fmt.Sprintf("%X", ch)
+	}
+	return strings.Join(hex, "")
+}
+
+// ensureInRange adjusts the passed value, if necessary, to ensure it is within
+// the passed min / max range.
+func ensureInRange(n int16, min int16, max int16) int16 {
+	if n < min {
+		return min
+	} else if n > max {
+		return max
+	} else {
+		return n
+	}
+}
+
+func GetStdFile(nFile int) (*os.File, uintptr) {
+	var file *os.File
+	switch nFile {
+	case syscall.STD_INPUT_HANDLE:
+		file = os.Stdin
+	case syscall.STD_OUTPUT_HANDLE:
+		file = os.Stdout
+	case syscall.STD_ERROR_HANDLE:
+		file = os.Stderr
+	default:
+		panic(fmt.Errorf("Invalid standard handle identifier: %v", nFile))
+	}
+
+	fd, err := syscall.GetStdHandle(nFile)
+	if err != nil {
+		panic(fmt.Errorf("Invalid standard handle identifier: %v -- %v", nFile, err))
+	}
+
+	return file, uintptr(fd)
+}
@@ -0,0 +1,327 @@
+// +build windows
+
+package winterm
+
+import (
+	"fmt"
+	"syscall"
+	"unsafe"
+)
+
+//===========================================================================================================
+// IMPORTANT NOTE:
+//
+//	The methods below make extensive use of the "unsafe" package to obtain the required pointers.
+//	Beginning in Go 1.3, the garbage collector may release local variables (e.g., incoming arguments, stack
+//	variables) the pointers reference *before* the API completes.
+//
+//  As a result, in those cases, the code must hint that the variables remain in active by invoking the
+//	dummy method "use" (see below). Newer versions of Go are planned to change the mechanism to no longer
+//	require unsafe pointers.
+//
+//	If you add or modify methods, ENSURE protection of local variables through the "use" builtin to inform
+//	the garbage collector the variables remain in use if:
+//
+//	-- The value is not a pointer (e.g., int32, struct)
+//	-- The value is not referenced by the method after passing the pointer to Windows
+//
+//	See http://golang.org/doc/go1.3.
+//===========================================================================================================
+
+var (
+	kernel32DLL = syscall.NewLazyDLL("kernel32.dll")
+
+	getConsoleCursorInfoProc       = kernel32DLL.NewProc("GetConsoleCursorInfo")
+	setConsoleCursorInfoProc       = kernel32DLL.NewProc("SetConsoleCursorInfo")
+	setConsoleCursorPositionProc   = kernel32DLL.NewProc("SetConsoleCursorPosition")
+	setConsoleModeProc             = kernel32DLL.NewProc("SetConsoleMode")
+	getConsoleScreenBufferInfoProc = kernel32DLL.NewProc("GetConsoleScreenBufferInfo")
+	setConsoleScreenBufferSizeProc = kernel32DLL.NewProc("SetConsoleScreenBufferSize")
+	scrollConsoleScreenBufferProc  = kernel32DLL.NewProc("ScrollConsoleScreenBufferA")
+	setConsoleTextAttributeProc    = kernel32DLL.NewProc("SetConsoleTextAttribute")
+	setConsoleWindowInfoProc       = kernel32DLL.NewProc("SetConsoleWindowInfo")
+	writeConsoleOutputProc         = kernel32DLL.NewProc("WriteConsoleOutputW")
+	readConsoleInputProc           = kernel32DLL.NewProc("ReadConsoleInputW")
+	waitForSingleObjectProc        = kernel32DLL.NewProc("WaitForSingleObject")
+)
+
+// Windows Console constants
+const (
+	// Console modes
+	// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx.
+	ENABLE_PROCESSED_INPUT        = 0x0001
+	ENABLE_LINE_INPUT             = 0x0002
+	ENABLE_ECHO_INPUT             = 0x0004
+	ENABLE_WINDOW_INPUT           = 0x0008
+	ENABLE_MOUSE_INPUT            = 0x0010
+	ENABLE_INSERT_MODE            = 0x0020
+	ENABLE_QUICK_EDIT_MODE        = 0x0040
+	ENABLE_EXTENDED_FLAGS         = 0x0080
+	ENABLE_AUTO_POSITION          = 0x0100
+	ENABLE_VIRTUAL_TERMINAL_INPUT = 0x0200
+
+	ENABLE_PROCESSED_OUTPUT            = 0x0001
+	ENABLE_WRAP_AT_EOL_OUTPUT          = 0x0002
+	ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004
+	DISABLE_NEWLINE_AUTO_RETURN        = 0x0008
+	ENABLE_LVB_GRID_WORLDWIDE          = 0x0010
+
+	// Character attributes
+	// Note:
+	// -- The attributes are combined to produce various colors (e.g., Blue + Green will create Cyan).
+	//    Clearing all foreground or background colors results in black; setting all creates white.
+	// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms682088(v=vs.85).aspx#_win32_character_attributes.
+	FOREGROUND_BLUE      uint16 = 0x0001
+	FOREGROUND_GREEN     uint16 = 0x0002
+	FOREGROUND_RED       uint16 = 0x0004
+	FOREGROUND_INTENSITY uint16 = 0x0008
+	FOREGROUND_MASK      uint16 = 0x000F
+
+	BACKGROUND_BLUE      uint16 = 0x0010
+	BACKGROUND_GREEN     uint16 = 0x0020
+	BACKGROUND_RED       uint16 = 0x0040
+	BACKGROUND_INTENSITY uint16 = 0x0080
+	BACKGROUND_MASK      uint16 = 0x00F0
+
+	COMMON_LVB_MASK          uint16 = 0xFF00
+	COMMON_LVB_REVERSE_VIDEO uint16 = 0x4000
+	COMMON_LVB_UNDERSCORE    uint16 = 0x8000
+
+	// Input event types
+	// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms683499(v=vs.85).aspx.
+	KEY_EVENT                = 0x0001
+	MOUSE_EVENT              = 0x0002
+	WINDOW_BUFFER_SIZE_EVENT = 0x0004
+	MENU_EVENT               = 0x0008
+	FOCUS_EVENT              = 0x0010
+
+	// WaitForSingleObject return codes
+	WAIT_ABANDONED = 0x00000080
+	WAIT_FAILED    = 0xFFFFFFFF
+	WAIT_SIGNALED  = 0x0000000
+	WAIT_TIMEOUT   = 0x00000102
+
+	// WaitForSingleObject wait duration
+	WAIT_INFINITE       = 0xFFFFFFFF
+	WAIT_ONE_SECOND     = 1000
+	WAIT_HALF_SECOND    = 500
+	WAIT_QUARTER_SECOND = 250
+)
+
+// Windows API Console types
+// -- See https://msdn.microsoft.com/en-us/library/windows/desktop/ms682101(v=vs.85).aspx for Console specific types (e.g., COORD)
+// -- See https://msdn.microsoft.com/en-us/library/aa296569(v=vs.60).aspx for comments on alignment
+type (
+	CHAR_INFO struct {
+		UnicodeChar uint16
+		Attributes  uint16
+	}
+
+	CONSOLE_CURSOR_INFO struct {
+		Size    uint32
+		Visible int32
+	}
+
+	CONSOLE_SCREEN_BUFFER_INFO struct {
+		Size              COORD
+		CursorPosition    COORD
+		Attributes        uint16
+		Window            SMALL_RECT
+		MaximumWindowSize COORD
+	}
+
+	COORD struct {
+		X int16
+		Y int16
+	}
+
+	SMALL_RECT struct {
+		Left   int16
+		Top    int16
+		Right  int16
+		Bottom int16
+	}
+
+	// INPUT_RECORD is a C/C++ union of which KEY_EVENT_RECORD is one case, it is also the largest
+	// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms683499(v=vs.85).aspx.
+	INPUT_RECORD struct {
+		EventType uint16
+		KeyEvent  KEY_EVENT_RECORD
+	}
+
+	KEY_EVENT_RECORD struct {
+		KeyDown         int32
+		RepeatCount     uint16
+		VirtualKeyCode  uint16
+		VirtualScanCode uint16
+		UnicodeChar     uint16
+		ControlKeyState uint32
+	}
+
+	WINDOW_BUFFER_SIZE struct {
+		Size COORD
+	}
+)
+
+// boolToBOOL converts a Go bool into a Windows int32.
+func boolToBOOL(f bool) int32 {
+	if f {
+		return int32(1)
+	} else {
+		return int32(0)
+	}
+}
+
+// GetConsoleCursorInfo retrieves information about the size and visiblity of the console cursor.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms683163(v=vs.85).aspx.
+func GetConsoleCursorInfo(handle uintptr, cursorInfo *CONSOLE_CURSOR_INFO) error {
+	r1, r2, err := getConsoleCursorInfoProc.Call(handle, uintptr(unsafe.Pointer(cursorInfo)), 0)
+	return checkError(r1, r2, err)
+}
+
+// SetConsoleCursorInfo sets the size and visiblity of the console cursor.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms686019(v=vs.85).aspx.
+func SetConsoleCursorInfo(handle uintptr, cursorInfo *CONSOLE_CURSOR_INFO) error {
+	r1, r2, err := setConsoleCursorInfoProc.Call(handle, uintptr(unsafe.Pointer(cursorInfo)), 0)
+	return checkError(r1, r2, err)
+}
+
+// SetConsoleCursorPosition location of the console cursor.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms686025(v=vs.85).aspx.
+func SetConsoleCursorPosition(handle uintptr, coord COORD) error {
+	r1, r2, err := setConsoleCursorPositionProc.Call(handle, coordToPointer(coord))
+	use(coord)
+	return checkError(r1, r2, err)
+}
+
+// GetConsoleMode gets the console mode for given file descriptor
+// See http://msdn.microsoft.com/en-us/library/windows/desktop/ms683167(v=vs.85).aspx.
+func GetConsoleMode(handle uintptr) (mode uint32, err error) {
+	err = syscall.GetConsoleMode(syscall.Handle(handle), &mode)
+	return mode, err
+}
+
+// SetConsoleMode sets the console mode for given file descriptor
+// See http://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx.
+func SetConsoleMode(handle uintptr, mode uint32) error {
+	r1, r2, err := setConsoleModeProc.Call(handle, uintptr(mode), 0)
+	use(mode)
+	return checkError(r1, r2, err)
+}
+
+// GetConsoleScreenBufferInfo retrieves information about the specified console screen buffer.
+// See http://msdn.microsoft.com/en-us/library/windows/desktop/ms683171(v=vs.85).aspx.
+func GetConsoleScreenBufferInfo(handle uintptr) (*CONSOLE_SCREEN_BUFFER_INFO, error) {
+	info := CONSOLE_SCREEN_BUFFER_INFO{}
+	err := checkError(getConsoleScreenBufferInfoProc.Call(handle, uintptr(unsafe.Pointer(&info)), 0))
+	if err != nil {
+		return nil, err
+	}
+	return &info, nil
+}
+
+func ScrollConsoleScreenBuffer(handle uintptr, scrollRect SMALL_RECT, clipRect SMALL_RECT, destOrigin COORD, char CHAR_INFO) error {
+	r1, r2, err := scrollConsoleScreenBufferProc.Call(handle, uintptr(unsafe.Pointer(&scrollRect)), uintptr(unsafe.Pointer(&clipRect)), coordToPointer(destOrigin), uintptr(unsafe.Pointer(&char)))
+	use(scrollRect)
+	use(clipRect)
+	use(destOrigin)
+	use(char)
+	return checkError(r1, r2, err)
+}
+
+// SetConsoleScreenBufferSize sets the size of the console screen buffer.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms686044(v=vs.85).aspx.
+func SetConsoleScreenBufferSize(handle uintptr, coord COORD) error {
+	r1, r2, err := setConsoleScreenBufferSizeProc.Call(handle, coordToPointer(coord))
+	use(coord)
+	return checkError(r1, r2, err)
+}
+
+// SetConsoleTextAttribute sets the attributes of characters written to the
+// console screen buffer by the WriteFile or WriteConsole function.
+// See http://msdn.microsoft.com/en-us/library/windows/desktop/ms686047(v=vs.85).aspx.
+func SetConsoleTextAttribute(handle uintptr, attribute uint16) error {
+	r1, r2, err := setConsoleTextAttributeProc.Call(handle, uintptr(attribute), 0)
+	use(attribute)
+	return checkError(r1, r2, err)
+}
+
+// SetConsoleWindowInfo sets the size and position of the console screen buffer's window.
+// Note that the size and location must be within and no larger than the backing console screen buffer.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms686125(v=vs.85).aspx.
+func SetConsoleWindowInfo(handle uintptr, isAbsolute bool, rect SMALL_RECT) error {
+	r1, r2, err := setConsoleWindowInfoProc.Call(handle, uintptr(boolToBOOL(isAbsolute)), uintptr(unsafe.Pointer(&rect)))
+	use(isAbsolute)
+	use(rect)
+	return checkError(r1, r2, err)
+}
+
+// WriteConsoleOutput writes the CHAR_INFOs from the provided buffer to the active console buffer.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms687404(v=vs.85).aspx.
+func WriteConsoleOutput(handle uintptr, buffer []CHAR_INFO, bufferSize COORD, bufferCoord COORD, writeRegion *SMALL_RECT) error {
+	r1, r2, err := writeConsoleOutputProc.Call(handle, uintptr(unsafe.Pointer(&buffer[0])), coordToPointer(bufferSize), coordToPointer(bufferCoord), uintptr(unsafe.Pointer(writeRegion)))
+	use(buffer)
+	use(bufferSize)
+	use(bufferCoord)
+	return checkError(r1, r2, err)
+}
+
+// ReadConsoleInput reads (and removes) data from the console input buffer.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms684961(v=vs.85).aspx.
+func ReadConsoleInput(handle uintptr, buffer []INPUT_RECORD, count *uint32) error {
+	r1, r2, err := readConsoleInputProc.Call(handle, uintptr(unsafe.Pointer(&buffer[0])), uintptr(len(buffer)), uintptr(unsafe.Pointer(count)))
+	use(buffer)
+	return checkError(r1, r2, err)
+}
+
+// WaitForSingleObject waits for the passed handle to be signaled.
+// It returns true if the handle was signaled; false otherwise.
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms687032(v=vs.85).aspx.
+func WaitForSingleObject(handle uintptr, msWait uint32) (bool, error) {
+	r1, _, err := waitForSingleObjectProc.Call(handle, uintptr(uint32(msWait)))
+	switch r1 {
+	case WAIT_ABANDONED, WAIT_TIMEOUT:
+		return false, nil
+	case WAIT_SIGNALED:
+		return true, nil
+	}
+	use(msWait)
+	return false, err
+}
+
+// String helpers
+func (info CONSOLE_SCREEN_BUFFER_INFO) String() string {
+	return fmt.Sprintf("Size(%v) Cursor(%v) Window(%v) Max(%v)", info.Size, info.CursorPosition, info.Window, info.MaximumWindowSize)
+}
+
+func (coord COORD) String() string {
+	return fmt.Sprintf("%v,%v", coord.X, coord.Y)
+}
+
+func (rect SMALL_RECT) String() string {
+	return fmt.Sprintf("(%v,%v),(%v,%v)", rect.Left, rect.Top, rect.Right, rect.Bottom)
+}
+
+// checkError evaluates the results of a Windows API call and returns the error if it failed.
+func checkError(r1, r2 uintptr, err error) error {
+	// Windows APIs return non-zero to indicate success
+	if r1 != 0 {
+		return nil
+	}
+
+	// Return the error if provided, otherwise default to EINVAL
+	if err != nil {
+		return err
+	}
+	return syscall.EINVAL
+}
+
+// coordToPointer converts a COORD into a uintptr (by fooling the type system).
+func coordToPointer(c COORD) uintptr {
+	// Note: This code assumes the two SHORTs are correctly laid out; the "cast" to uint32 is just to get a pointer to pass.
+	return uintptr(*((*uint32)(unsafe.Pointer(&c))))
+}
+
+// use is a no-op, but the compiler cannot see that it is.
+// Calling use(p) ensures that p is kept live until that point.
+func use(p interface{}) {}
@@ -0,0 +1,100 @@
+// +build windows
+
+package winterm
+
+import "github.com/Azure/go-ansiterm"
+
+const (
+	FOREGROUND_COLOR_MASK = FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE
+	BACKGROUND_COLOR_MASK = BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE
+)
+
+// collectAnsiIntoWindowsAttributes modifies the passed Windows text mode flags to reflect the
+// request represented by the passed ANSI mode.
+func collectAnsiIntoWindowsAttributes(windowsMode uint16, inverted bool, baseMode uint16, ansiMode int16) (uint16, bool) {
+	switch ansiMode {
+
+	// Mode styles
+	case ansiterm.ANSI_SGR_BOLD:
+		windowsMode = windowsMode | FOREGROUND_INTENSITY
+
+	case ansiterm.ANSI_SGR_DIM, ansiterm.ANSI_SGR_BOLD_DIM_OFF:
+		windowsMode &^= FOREGROUND_INTENSITY
+
+	case ansiterm.ANSI_SGR_UNDERLINE:
+		windowsMode = windowsMode | COMMON_LVB_UNDERSCORE
+
+	case ansiterm.ANSI_SGR_REVERSE:
+		inverted = true
+
+	case ansiterm.ANSI_SGR_REVERSE_OFF:
+		inverted = false
+
+	case ansiterm.ANSI_SGR_UNDERLINE_OFF:
+		windowsMode &^= COMMON_LVB_UNDERSCORE
+
+		// Foreground colors
+	case ansiterm.ANSI_SGR_FOREGROUND_DEFAULT:
+		windowsMode = (windowsMode &^ FOREGROUND_MASK) | (baseMode & FOREGROUND_MASK)
+
+	case ansiterm.ANSI_SGR_FOREGROUND_BLACK:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK)
+
+	case ansiterm.ANSI_SGR_FOREGROUND_RED:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_RED
+
+	case ansiterm.ANSI_SGR_FOREGROUND_GREEN:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_GREEN
+
+	case ansiterm.ANSI_SGR_FOREGROUND_YELLOW:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_RED | FOREGROUND_GREEN
+
+	case ansiterm.ANSI_SGR_FOREGROUND_BLUE:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_FOREGROUND_MAGENTA:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_RED | FOREGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_FOREGROUND_CYAN:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_GREEN | FOREGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_FOREGROUND_WHITE:
+		windowsMode = (windowsMode &^ FOREGROUND_COLOR_MASK) | FOREGROUND_RED | FOREGROUND_GREEN | FOREGROUND_BLUE
+
+		// Background colors
+	case ansiterm.ANSI_SGR_BACKGROUND_DEFAULT:
+		// Black with no intensity
+		windowsMode = (windowsMode &^ BACKGROUND_MASK) | (baseMode & BACKGROUND_MASK)
+
+	case ansiterm.ANSI_SGR_BACKGROUND_BLACK:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK)
+
+	case ansiterm.ANSI_SGR_BACKGROUND_RED:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_RED
+
+	case ansiterm.ANSI_SGR_BACKGROUND_GREEN:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_GREEN
+
+	case ansiterm.ANSI_SGR_BACKGROUND_YELLOW:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_RED | BACKGROUND_GREEN
+
+	case ansiterm.ANSI_SGR_BACKGROUND_BLUE:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_BACKGROUND_MAGENTA:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_RED | BACKGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_BACKGROUND_CYAN:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_GREEN | BACKGROUND_BLUE
+
+	case ansiterm.ANSI_SGR_BACKGROUND_WHITE:
+		windowsMode = (windowsMode &^ BACKGROUND_COLOR_MASK) | BACKGROUND_RED | BACKGROUND_GREEN | BACKGROUND_BLUE
+	}
+
+	return windowsMode, inverted
+}
+
+// invertAttributes inverts the foreground and background colors of a Windows attributes value
+func invertAttributes(windowsMode uint16) uint16 {
+	return (COMMON_LVB_MASK & windowsMode) | ((FOREGROUND_MASK & windowsMode) << 4) | ((BACKGROUND_MASK & windowsMode) >> 4)
+}
@@ -0,0 +1,101 @@
+// +build windows
+
+package winterm
+
+const (
+	horizontal = iota
+	vertical
+)
+
+func (h *windowsAnsiEventHandler) getCursorWindow(info *CONSOLE_SCREEN_BUFFER_INFO) SMALL_RECT {
+	if h.originMode {
+		sr := h.effectiveSr(info.Window)
+		return SMALL_RECT{
+			Top:    sr.top,
+			Bottom: sr.bottom,
+			Left:   0,
+			Right:  info.Size.X - 1,
+		}
+	} else {
+		return SMALL_RECT{
+			Top:    info.Window.Top,
+			Bottom: info.Window.Bottom,
+			Left:   0,
+			Right:  info.Size.X - 1,
+		}
+	}
+}
+
+// setCursorPosition sets the cursor to the specified position, bounded to the screen size
+func (h *windowsAnsiEventHandler) setCursorPosition(position COORD, window SMALL_RECT) error {
+	position.X = ensureInRange(position.X, window.Left, window.Right)
+	position.Y = ensureInRange(position.Y, window.Top, window.Bottom)
+	err := SetConsoleCursorPosition(h.fd, position)
+	if err != nil {
+		return err
+	}
+	h.logf("Cursor position set: (%d, %d)", position.X, position.Y)
+	return err
+}
+
+func (h *windowsAnsiEventHandler) moveCursorVertical(param int) error {
+	return h.moveCursor(vertical, param)
+}
+
+func (h *windowsAnsiEventHandler) moveCursorHorizontal(param int) error {
+	return h.moveCursor(horizontal, param)
+}
+
+func (h *windowsAnsiEventHandler) moveCursor(moveMode int, param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	position := info.CursorPosition
+	switch moveMode {
+	case horizontal:
+		position.X += int16(param)
+	case vertical:
+		position.Y += int16(param)
+	}
+
+	if err = h.setCursorPosition(position, h.getCursorWindow(info)); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) moveCursorLine(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	position := info.CursorPosition
+	position.X = 0
+	position.Y += int16(param)
+
+	if err = h.setCursorPosition(position, h.getCursorWindow(info)); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) moveCursorColumn(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	position := info.CursorPosition
+	position.X = int16(param) - 1
+
+	if err = h.setCursorPosition(position, h.getCursorWindow(info)); err != nil {
+		return err
+	}
+
+	return nil
+}
@@ -0,0 +1,84 @@
+// +build windows
+
+package winterm
+
+import "github.com/Azure/go-ansiterm"
+
+func (h *windowsAnsiEventHandler) clearRange(attributes uint16, fromCoord COORD, toCoord COORD) error {
+	// Ignore an invalid (negative area) request
+	if toCoord.Y < fromCoord.Y {
+		return nil
+	}
+
+	var err error
+
+	var coordStart = COORD{}
+	var coordEnd = COORD{}
+
+	xCurrent, yCurrent := fromCoord.X, fromCoord.Y
+	xEnd, yEnd := toCoord.X, toCoord.Y
+
+	// Clear any partial initial line
+	if xCurrent > 0 {
+		coordStart.X, coordStart.Y = xCurrent, yCurrent
+		coordEnd.X, coordEnd.Y = xEnd, yCurrent
+
+		err = h.clearRect(attributes, coordStart, coordEnd)
+		if err != nil {
+			return err
+		}
+
+		xCurrent = 0
+		yCurrent += 1
+	}
+
+	// Clear intervening rectangular section
+	if yCurrent < yEnd {
+		coordStart.X, coordStart.Y = xCurrent, yCurrent
+		coordEnd.X, coordEnd.Y = xEnd, yEnd-1
+
+		err = h.clearRect(attributes, coordStart, coordEnd)
+		if err != nil {
+			return err
+		}
+
+		xCurrent = 0
+		yCurrent = yEnd
+	}
+
+	// Clear remaining partial ending line
+	coordStart.X, coordStart.Y = xCurrent, yCurrent
+	coordEnd.X, coordEnd.Y = xEnd, yEnd
+
+	err = h.clearRect(attributes, coordStart, coordEnd)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) clearRect(attributes uint16, fromCoord COORD, toCoord COORD) error {
+	region := SMALL_RECT{Top: fromCoord.Y, Left: fromCoord.X, Bottom: toCoord.Y, Right: toCoord.X}
+	width := toCoord.X - fromCoord.X + 1
+	height := toCoord.Y - fromCoord.Y + 1
+	size := uint32(width) * uint32(height)
+
+	if size <= 0 {
+		return nil
+	}
+
+	buffer := make([]CHAR_INFO, size)
+
+	char := CHAR_INFO{ansiterm.FILL_CHARACTER, attributes}
+	for i := 0; i < int(size); i++ {
+		buffer[i] = char
+	}
+
+	err := WriteConsoleOutput(h.fd, buffer, COORD{X: width, Y: height}, COORD{X: 0, Y: 0}, &region)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
@@ -0,0 +1,118 @@
+// +build windows
+
+package winterm
+
+// effectiveSr gets the current effective scroll region in buffer coordinates
+func (h *windowsAnsiEventHandler) effectiveSr(window SMALL_RECT) scrollRegion {
+	top := addInRange(window.Top, h.sr.top, window.Top, window.Bottom)
+	bottom := addInRange(window.Top, h.sr.bottom, window.Top, window.Bottom)
+	if top >= bottom {
+		top = window.Top
+		bottom = window.Bottom
+	}
+	return scrollRegion{top: top, bottom: bottom}
+}
+
+func (h *windowsAnsiEventHandler) scrollUp(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	sr := h.effectiveSr(info.Window)
+	return h.scroll(param, sr, info)
+}
+
+func (h *windowsAnsiEventHandler) scrollDown(param int) error {
+	return h.scrollUp(-param)
+}
+
+func (h *windowsAnsiEventHandler) deleteLines(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	start := info.CursorPosition.Y
+	sr := h.effectiveSr(info.Window)
+	// Lines cannot be inserted or deleted outside the scrolling region.
+	if start >= sr.top && start <= sr.bottom {
+		sr.top = start
+		return h.scroll(param, sr, info)
+	} else {
+		return nil
+	}
+}
+
+func (h *windowsAnsiEventHandler) insertLines(param int) error {
+	return h.deleteLines(-param)
+}
+
+// scroll scrolls the provided scroll region by param lines. The scroll region is in buffer coordinates.
+func (h *windowsAnsiEventHandler) scroll(param int, sr scrollRegion, info *CONSOLE_SCREEN_BUFFER_INFO) error {
+	h.logf("scroll: scrollTop: %d, scrollBottom: %d", sr.top, sr.bottom)
+	h.logf("scroll: windowTop: %d, windowBottom: %d", info.Window.Top, info.Window.Bottom)
+
+	// Copy from and clip to the scroll region (full buffer width)
+	scrollRect := SMALL_RECT{
+		Top:    sr.top,
+		Bottom: sr.bottom,
+		Left:   0,
+		Right:  info.Size.X - 1,
+	}
+
+	// Origin to which area should be copied
+	destOrigin := COORD{
+		X: 0,
+		Y: sr.top - int16(param),
+	}
+
+	char := CHAR_INFO{
+		UnicodeChar: ' ',
+		Attributes:  h.attributes,
+	}
+
+	if err := ScrollConsoleScreenBuffer(h.fd, scrollRect, scrollRect, destOrigin, char); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) deleteCharacters(param int) error {
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+	return h.scrollLine(param, info.CursorPosition, info)
+}
+
+func (h *windowsAnsiEventHandler) insertCharacters(param int) error {
+	return h.deleteCharacters(-param)
+}
+
+// scrollLine scrolls a line horizontally starting at the provided position by a number of columns.
+func (h *windowsAnsiEventHandler) scrollLine(columns int, position COORD, info *CONSOLE_SCREEN_BUFFER_INFO) error {
+	// Copy from and clip to the scroll region (full buffer width)
+	scrollRect := SMALL_RECT{
+		Top:    position.Y,
+		Bottom: position.Y,
+		Left:   position.X,
+		Right:  info.Size.X - 1,
+	}
+
+	// Origin to which area should be copied
+	destOrigin := COORD{
+		X: position.X - int16(columns),
+		Y: position.Y,
+	}
+
+	char := CHAR_INFO{
+		UnicodeChar: ' ',
+		Attributes:  h.attributes,
+	}
+
+	if err := ScrollConsoleScreenBuffer(h.fd, scrollRect, scrollRect, destOrigin, char); err != nil {
+		return err
+	}
+	return nil
+}
@@ -0,0 +1,9 @@
+// +build windows
+
+package winterm
+
+// AddInRange increments a value by the passed quantity while ensuring the values
+// always remain within the supplied min / max range.
+func addInRange(n int16, increment int16, min int16, max int16) int16 {
+	return ensureInRange(n+increment, min, max)
+}
@@ -0,0 +1,743 @@
+// +build windows
+
+package winterm
+
+import (
+	"bytes"
+	"log"
+	"os"
+	"strconv"
+
+	"github.com/Azure/go-ansiterm"
+)
+
+type windowsAnsiEventHandler struct {
+	fd             uintptr
+	file           *os.File
+	infoReset      *CONSOLE_SCREEN_BUFFER_INFO
+	sr             scrollRegion
+	buffer         bytes.Buffer
+	attributes     uint16
+	inverted       bool
+	wrapNext       bool
+	drewMarginByte bool
+	originMode     bool
+	marginByte     byte
+	curInfo        *CONSOLE_SCREEN_BUFFER_INFO
+	curPos         COORD
+	logf           func(string, ...interface{})
+}
+
+type Option func(*windowsAnsiEventHandler)
+
+func WithLogf(f func(string, ...interface{})) Option {
+	return func(w *windowsAnsiEventHandler) {
+		w.logf = f
+	}
+}
+
+func CreateWinEventHandler(fd uintptr, file *os.File, opts ...Option) ansiterm.AnsiEventHandler {
+	infoReset, err := GetConsoleScreenBufferInfo(fd)
+	if err != nil {
+		return nil
+	}
+
+	h := &windowsAnsiEventHandler{
+		fd:         fd,
+		file:       file,
+		infoReset:  infoReset,
+		attributes: infoReset.Attributes,
+	}
+	for _, o := range opts {
+		o(h)
+	}
+
+	if isDebugEnv := os.Getenv(ansiterm.LogEnv); isDebugEnv == "1" {
+		logFile, _ := os.Create("winEventHandler.log")
+		logger := log.New(logFile, "", log.LstdFlags)
+		if h.logf != nil {
+			l := h.logf
+			h.logf = func(s string, v ...interface{}) {
+				l(s, v...)
+				logger.Printf(s, v...)
+			}
+		} else {
+			h.logf = logger.Printf
+		}
+	}
+
+	if h.logf == nil {
+		h.logf = func(string, ...interface{}) {}
+	}
+
+	return h
+}
+
+type scrollRegion struct {
+	top    int16
+	bottom int16
+}
+
+// simulateLF simulates a LF or CR+LF by scrolling if necessary to handle the
+// current cursor position and scroll region settings, in which case it returns
+// true. If no special handling is necessary, then it does nothing and returns
+// false.
+//
+// In the false case, the caller should ensure that a carriage return
+// and line feed are inserted or that the text is otherwise wrapped.
+func (h *windowsAnsiEventHandler) simulateLF(includeCR bool) (bool, error) {
+	if h.wrapNext {
+		if err := h.Flush(); err != nil {
+			return false, err
+		}
+		h.clearWrap()
+	}
+	pos, info, err := h.getCurrentInfo()
+	if err != nil {
+		return false, err
+	}
+	sr := h.effectiveSr(info.Window)
+	if pos.Y == sr.bottom {
+		// Scrolling is necessary. Let Windows automatically scroll if the scrolling region
+		// is the full window.
+		if sr.top == info.Window.Top && sr.bottom == info.Window.Bottom {
+			if includeCR {
+				pos.X = 0
+				h.updatePos(pos)
+			}
+			return false, nil
+		}
+
+		// A custom scroll region is active. Scroll the window manually to simulate
+		// the LF.
+		if err := h.Flush(); err != nil {
+			return false, err
+		}
+		h.logf("Simulating LF inside scroll region")
+		if err := h.scrollUp(1); err != nil {
+			return false, err
+		}
+		if includeCR {
+			pos.X = 0
+			if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
+				return false, err
+			}
+		}
+		return true, nil
+
+	} else if pos.Y < info.Window.Bottom {
+		// Let Windows handle the LF.
+		pos.Y++
+		if includeCR {
+			pos.X = 0
+		}
+		h.updatePos(pos)
+		return false, nil
+	} else {
+		// The cursor is at the bottom of the screen but outside the scroll
+		// region. Skip the LF.
+		h.logf("Simulating LF outside scroll region")
+		if includeCR {
+			if err := h.Flush(); err != nil {
+				return false, err
+			}
+			pos.X = 0
+			if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
+				return false, err
+			}
+		}
+		return true, nil
+	}
+}
+
+// executeLF executes a LF without a CR.
+func (h *windowsAnsiEventHandler) executeLF() error {
+	handled, err := h.simulateLF(false)
+	if err != nil {
+		return err
+	}
+	if !handled {
+		// Windows LF will reset the cursor column position. Write the LF
+		// and restore the cursor position.
+		pos, _, err := h.getCurrentInfo()
+		if err != nil {
+			return err
+		}
+		h.buffer.WriteByte(ansiterm.ANSI_LINE_FEED)
+		if pos.X != 0 {
+			if err := h.Flush(); err != nil {
+				return err
+			}
+			h.logf("Resetting cursor position for LF without CR")
+			if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) Print(b byte) error {
+	if h.wrapNext {
+		h.buffer.WriteByte(h.marginByte)
+		h.clearWrap()
+		if _, err := h.simulateLF(true); err != nil {
+			return err
+		}
+	}
+	pos, info, err := h.getCurrentInfo()
+	if err != nil {
+		return err
+	}
+	if pos.X == info.Size.X-1 {
+		h.wrapNext = true
+		h.marginByte = b
+	} else {
+		pos.X++
+		h.updatePos(pos)
+		h.buffer.WriteByte(b)
+	}
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) Execute(b byte) error {
+	switch b {
+	case ansiterm.ANSI_TAB:
+		h.logf("Execute(TAB)")
+		// Move to the next tab stop, but preserve auto-wrap if already set.
+		if !h.wrapNext {
+			pos, info, err := h.getCurrentInfo()
+			if err != nil {
+				return err
+			}
+			pos.X = (pos.X + 8) - pos.X%8
+			if pos.X >= info.Size.X {
+				pos.X = info.Size.X - 1
+			}
+			if err := h.Flush(); err != nil {
+				return err
+			}
+			if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
+				return err
+			}
+		}
+		return nil
+
+	case ansiterm.ANSI_BEL:
+		h.buffer.WriteByte(ansiterm.ANSI_BEL)
+		return nil
+
+	case ansiterm.ANSI_BACKSPACE:
+		if h.wrapNext {
+			if err := h.Flush(); err != nil {
+				return err
+			}
+			h.clearWrap()
+		}
+		pos, _, err := h.getCurrentInfo()
+		if err != nil {
+			return err
+		}
+		if pos.X > 0 {
+			pos.X--
+			h.updatePos(pos)
+			h.buffer.WriteByte(ansiterm.ANSI_BACKSPACE)
+		}
+		return nil
+
+	case ansiterm.ANSI_VERTICAL_TAB, ansiterm.ANSI_FORM_FEED:
+		// Treat as true LF.
+		return h.executeLF()
+
+	case ansiterm.ANSI_LINE_FEED:
+		// Simulate a CR and LF for now since there is no way in go-ansiterm
+		// to tell if the LF should include CR (and more things break when it's
+		// missing than when it's incorrectly added).
+		handled, err := h.simulateLF(true)
+		if handled || err != nil {
+			return err
+		}
+		return h.buffer.WriteByte(ansiterm.ANSI_LINE_FEED)
+
+	case ansiterm.ANSI_CARRIAGE_RETURN:
+		if h.wrapNext {
+			if err := h.Flush(); err != nil {
+				return err
+			}
+			h.clearWrap()
+		}
+		pos, _, err := h.getCurrentInfo()
+		if err != nil {
+			return err
+		}
+		if pos.X != 0 {
+			pos.X = 0
+			h.updatePos(pos)
+			h.buffer.WriteByte(ansiterm.ANSI_CARRIAGE_RETURN)
+		}
+		return nil
+
+	default:
+		return nil
+	}
+}
+
+func (h *windowsAnsiEventHandler) CUU(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CUU: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorVertical(-param)
+}
+
+func (h *windowsAnsiEventHandler) CUD(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CUD: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorVertical(param)
+}
+
+func (h *windowsAnsiEventHandler) CUF(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CUF: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorHorizontal(param)
+}
+
+func (h *windowsAnsiEventHandler) CUB(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CUB: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorHorizontal(-param)
+}
+
+func (h *windowsAnsiEventHandler) CNL(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CNL: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorLine(param)
+}
+
+func (h *windowsAnsiEventHandler) CPL(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CPL: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorLine(-param)
+}
+
+func (h *windowsAnsiEventHandler) CHA(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CHA: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.moveCursorColumn(param)
+}
+
+func (h *windowsAnsiEventHandler) VPA(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("VPA: [[%d]]", param)
+	h.clearWrap()
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+	window := h.getCursorWindow(info)
+	position := info.CursorPosition
+	position.Y = window.Top + int16(param) - 1
+	return h.setCursorPosition(position, window)
+}
+
+func (h *windowsAnsiEventHandler) CUP(row int, col int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("CUP: [[%d %d]]", row, col)
+	h.clearWrap()
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	window := h.getCursorWindow(info)
+	position := COORD{window.Left + int16(col) - 1, window.Top + int16(row) - 1}
+	return h.setCursorPosition(position, window)
+}
+
+func (h *windowsAnsiEventHandler) HVP(row int, col int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("HVP: [[%d %d]]", row, col)
+	h.clearWrap()
+	return h.CUP(row, col)
+}
+
+func (h *windowsAnsiEventHandler) DECTCEM(visible bool) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DECTCEM: [%v]", []string{strconv.FormatBool(visible)})
+	h.clearWrap()
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) DECOM(enable bool) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DECOM: [%v]", []string{strconv.FormatBool(enable)})
+	h.clearWrap()
+	h.originMode = enable
+	return h.CUP(1, 1)
+}
+
+func (h *windowsAnsiEventHandler) DECCOLM(use132 bool) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DECCOLM: [%v]", []string{strconv.FormatBool(use132)})
+	h.clearWrap()
+	if err := h.ED(2); err != nil {
+		return err
+	}
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+	targetWidth := int16(80)
+	if use132 {
+		targetWidth = 132
+	}
+	if info.Size.X < targetWidth {
+		if err := SetConsoleScreenBufferSize(h.fd, COORD{targetWidth, info.Size.Y}); err != nil {
+			h.logf("set buffer failed: %v", err)
+			return err
+		}
+	}
+	window := info.Window
+	window.Left = 0
+	window.Right = targetWidth - 1
+	if err := SetConsoleWindowInfo(h.fd, true, window); err != nil {
+		h.logf("set window failed: %v", err)
+		return err
+	}
+	if info.Size.X > targetWidth {
+		if err := SetConsoleScreenBufferSize(h.fd, COORD{targetWidth, info.Size.Y}); err != nil {
+			h.logf("set buffer failed: %v", err)
+			return err
+		}
+	}
+	return SetConsoleCursorPosition(h.fd, COORD{0, 0})
+}
+
+func (h *windowsAnsiEventHandler) ED(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("ED: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+
+	// [J  -- Erases from the cursor to the end of the screen, including the cursor position.
+	// [1J -- Erases from the beginning of the screen to the cursor, including the cursor position.
+	// [2J -- Erases the complete display. The cursor does not move.
+	// Notes:
+	// -- Clearing the entire buffer, versus just the Window, works best for Windows Consoles
+
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	var start COORD
+	var end COORD
+
+	switch param {
+	case 0:
+		start = info.CursorPosition
+		end = COORD{info.Size.X - 1, info.Size.Y - 1}
+
+	case 1:
+		start = COORD{0, 0}
+		end = info.CursorPosition
+
+	case 2:
+		start = COORD{0, 0}
+		end = COORD{info.Size.X - 1, info.Size.Y - 1}
+	}
+
+	err = h.clearRange(h.attributes, start, end)
+	if err != nil {
+		return err
+	}
+
+	// If the whole buffer was cleared, move the window to the top while preserving
+	// the window-relative cursor position.
+	if param == 2 {
+		pos := info.CursorPosition
+		window := info.Window
+		pos.Y -= window.Top
+		window.Bottom -= window.Top
+		window.Top = 0
+		if err := SetConsoleCursorPosition(h.fd, pos); err != nil {
+			return err
+		}
+		if err := SetConsoleWindowInfo(h.fd, true, window); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) EL(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("EL: [%v]", strconv.Itoa(param))
+	h.clearWrap()
+
+	// [K  -- Erases from the cursor to the end of the line, including the cursor position.
+	// [1K -- Erases from the beginning of the line to the cursor, including the cursor position.
+	// [2K -- Erases the complete line.
+
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	var start COORD
+	var end COORD
+
+	switch param {
+	case 0:
+		start = info.CursorPosition
+		end = COORD{info.Size.X, info.CursorPosition.Y}
+
+	case 1:
+		start = COORD{0, info.CursorPosition.Y}
+		end = info.CursorPosition
+
+	case 2:
+		start = COORD{0, info.CursorPosition.Y}
+		end = COORD{info.Size.X, info.CursorPosition.Y}
+	}
+
+	err = h.clearRange(h.attributes, start, end)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) IL(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("IL: [%v]", strconv.Itoa(param))
+	h.clearWrap()
+	return h.insertLines(param)
+}
+
+func (h *windowsAnsiEventHandler) DL(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DL: [%v]", strconv.Itoa(param))
+	h.clearWrap()
+	return h.deleteLines(param)
+}
+
+func (h *windowsAnsiEventHandler) ICH(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("ICH: [%v]", strconv.Itoa(param))
+	h.clearWrap()
+	return h.insertCharacters(param)
+}
+
+func (h *windowsAnsiEventHandler) DCH(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DCH: [%v]", strconv.Itoa(param))
+	h.clearWrap()
+	return h.deleteCharacters(param)
+}
+
+func (h *windowsAnsiEventHandler) SGR(params []int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	strings := []string{}
+	for _, v := range params {
+		strings = append(strings, strconv.Itoa(v))
+	}
+
+	h.logf("SGR: [%v]", strings)
+
+	if len(params) <= 0 {
+		h.attributes = h.infoReset.Attributes
+		h.inverted = false
+	} else {
+		for _, attr := range params {
+
+			if attr == ansiterm.ANSI_SGR_RESET {
+				h.attributes = h.infoReset.Attributes
+				h.inverted = false
+				continue
+			}
+
+			h.attributes, h.inverted = collectAnsiIntoWindowsAttributes(h.attributes, h.inverted, h.infoReset.Attributes, int16(attr))
+		}
+	}
+
+	attributes := h.attributes
+	if h.inverted {
+		attributes = invertAttributes(attributes)
+	}
+	err := SetConsoleTextAttribute(h.fd, attributes)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) SU(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("SU: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.scrollUp(param)
+}
+
+func (h *windowsAnsiEventHandler) SD(param int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("SD: [%v]", []string{strconv.Itoa(param)})
+	h.clearWrap()
+	return h.scrollDown(param)
+}
+
+func (h *windowsAnsiEventHandler) DA(params []string) error {
+	h.logf("DA: [%v]", params)
+	// DA cannot be implemented because it must send data on the VT100 input stream,
+	// which is not available to go-ansiterm.
+	return nil
+}
+
+func (h *windowsAnsiEventHandler) DECSTBM(top int, bottom int) error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("DECSTBM: [%d, %d]", top, bottom)
+
+	// Windows is 0 indexed, Linux is 1 indexed
+	h.sr.top = int16(top - 1)
+	h.sr.bottom = int16(bottom - 1)
+
+	// This command also moves the cursor to the origin.
+	h.clearWrap()
+	return h.CUP(1, 1)
+}
+
+func (h *windowsAnsiEventHandler) RI() error {
+	if err := h.Flush(); err != nil {
+		return err
+	}
+	h.logf("RI: []")
+	h.clearWrap()
+
+	info, err := GetConsoleScreenBufferInfo(h.fd)
+	if err != nil {
+		return err
+	}
+
+	sr := h.effectiveSr(info.Window)
+	if info.CursorPosition.Y == sr.top {
+		return h.scrollDown(1)
+	}
+
+	return h.moveCursorVertical(-1)
+}
+
+func (h *windowsAnsiEventHandler) IND() error {
+	h.logf("IND: []")
+	return h.executeLF()
+}
+
+func (h *windowsAnsiEventHandler) Flush() error {
+	h.curInfo = nil
+	if h.buffer.Len() > 0 {
+		h.logf("Flush: [%s]", h.buffer.Bytes())
+		if _, err := h.buffer.WriteTo(h.file); err != nil {
+			return err
+		}
+	}
+
+	if h.wrapNext && !h.drewMarginByte {
+		h.logf("Flush: drawing margin byte '%c'", h.marginByte)
+
+		info, err := GetConsoleScreenBufferInfo(h.fd)
+		if err != nil {
+			return err
+		}
+
+		charInfo := []CHAR_INFO{{UnicodeChar: uint16(h.marginByte), Attributes: info.Attributes}}
+		size := COORD{1, 1}
+		position := COORD{0, 0}
+		region := SMALL_RECT{Left: info.CursorPosition.X, Top: info.CursorPosition.Y, Right: info.CursorPosition.X, Bottom: info.CursorPosition.Y}
+		if err := WriteConsoleOutput(h.fd, charInfo, size, position, &region); err != nil {
+			return err
+		}
+		h.drewMarginByte = true
+	}
+	return nil
+}
+
+// cacheConsoleInfo ensures that the current console screen information has been queried
+// since the last call to Flush(). It must be called before accessing h.curInfo or h.curPos.
+func (h *windowsAnsiEventHandler) getCurrentInfo() (COORD, *CONSOLE_SCREEN_BUFFER_INFO, error) {
+	if h.curInfo == nil {
+		info, err := GetConsoleScreenBufferInfo(h.fd)
+		if err != nil {
+			return COORD{}, nil, err
+		}
+		h.curInfo = info
+		h.curPos = info.CursorPosition
+	}
+	return h.curPos, h.curInfo, nil
+}
+
+func (h *windowsAnsiEventHandler) updatePos(pos COORD) {
+	if h.curInfo == nil {
+		panic("failed to call getCurrentInfo before calling updatePos")
+	}
+	h.curPos = pos
+}
+
+// clearWrap clears the state where the cursor is in the margin
+// waiting for the next character before wrapping the line. This must
+// be done before most operations that act on the cursor.
+func (h *windowsAnsiEventHandler) clearWrap() {
+	h.wrapNext = false
+	h.drewMarginByte = false
+}
@@ -0,0 +1 @@
+*.exe
@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Microsoft
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
@@ -0,0 +1,22 @@
+# go-winio
+
+This repository contains utilities for efficiently performing Win32 IO operations in
+Go. Currently, this is focused on accessing named pipes and other file handles, and
+for using named pipes as a net transport.
+
+This code relies on IO completion ports to avoid blocking IO on system threads, allowing Go
+to reuse the thread to schedule another goroutine. This limits support to Windows Vista and
+newer operating systems. This is similar to the implementation of network sockets in Go's net
+package.
+
+Please see the LICENSE file for licensing information.
+
+This project has adopted the [Microsoft Open Source Code of
+Conduct](https://opensource.microsoft.com/codeofconduct/). For more information
+see the [Code of Conduct
+FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact
+[opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional
+questions or comments.
+
+Thanks to natefinch for the inspiration for this library. See https://github.com/natefinch/npipe
+for another named pipe implementation.
@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@@ -0,0 +1,280 @@
+// +build windows
+
+package winio
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"runtime"
+	"syscall"
+	"unicode/utf16"
+)
+
+//sys backupRead(h syscall.Handle, b []byte, bytesRead *uint32, abort bool, processSecurity bool, context *uintptr) (err error) = BackupRead
+//sys backupWrite(h syscall.Handle, b []byte, bytesWritten *uint32, abort bool, processSecurity bool, context *uintptr) (err error) = BackupWrite
+
+const (
+	BackupData = uint32(iota + 1)
+	BackupEaData
+	BackupSecurity
+	BackupAlternateData
+	BackupLink
+	BackupPropertyData
+	BackupObjectId
+	BackupReparseData
+	BackupSparseBlock
+	BackupTxfsData
+)
+
+const (
+	StreamSparseAttributes = uint32(8)
+)
+
+const (
+	WRITE_DAC              = 0x40000
+	WRITE_OWNER            = 0x80000
+	ACCESS_SYSTEM_SECURITY = 0x1000000
+)
+
+// BackupHeader represents a backup stream of a file.
+type BackupHeader struct {
+	Id         uint32 // The backup stream ID
+	Attributes uint32 // Stream attributes
+	Size       int64  // The size of the stream in bytes
+	Name       string // The name of the stream (for BackupAlternateData only).
+	Offset     int64  // The offset of the stream in the file (for BackupSparseBlock only).
+}
+
+type win32StreamId struct {
+	StreamId   uint32
+	Attributes uint32
+	Size       uint64
+	NameSize   uint32
+}
+
+// BackupStreamReader reads from a stream produced by the BackupRead Win32 API and produces a series
+// of BackupHeader values.
+type BackupStreamReader struct {
+	r         io.Reader
+	bytesLeft int64
+}
+
+// NewBackupStreamReader produces a BackupStreamReader from any io.Reader.
+func NewBackupStreamReader(r io.Reader) *BackupStreamReader {
+	return &BackupStreamReader{r, 0}
+}
+
+// Next returns the next backup stream and prepares for calls to Read(). It skips the remainder of the current stream if
+// it was not completely read.
+func (r *BackupStreamReader) Next() (*BackupHeader, error) {
+	if r.bytesLeft > 0 {
+		if s, ok := r.r.(io.Seeker); ok {
+			// Make sure Seek on io.SeekCurrent sometimes succeeds
+			// before trying the actual seek.
+			if _, err := s.Seek(0, io.SeekCurrent); err == nil {
+				if _, err = s.Seek(r.bytesLeft, io.SeekCurrent); err != nil {
+					return nil, err
+				}
+				r.bytesLeft = 0
+			}
+		}
+		if _, err := io.Copy(ioutil.Discard, r); err != nil {
+			return nil, err
+		}
+	}
+	var wsi win32StreamId
+	if err := binary.Read(r.r, binary.LittleEndian, &wsi); err != nil {
+		return nil, err
+	}
+	hdr := &BackupHeader{
+		Id:         wsi.StreamId,
+		Attributes: wsi.Attributes,
+		Size:       int64(wsi.Size),
+	}
+	if wsi.NameSize != 0 {
+		name := make([]uint16, int(wsi.NameSize/2))
+		if err := binary.Read(r.r, binary.LittleEndian, name); err != nil {
+			return nil, err
+		}
+		hdr.Name = syscall.UTF16ToString(name)
+	}
+	if wsi.StreamId == BackupSparseBlock {
+		if err := binary.Read(r.r, binary.LittleEndian, &hdr.Offset); err != nil {
+			return nil, err
+		}
+		hdr.Size -= 8
+	}
+	r.bytesLeft = hdr.Size
+	return hdr, nil
+}
+
+// Read reads from the current backup stream.
+func (r *BackupStreamReader) Read(b []byte) (int, error) {
+	if r.bytesLeft == 0 {
+		return 0, io.EOF
+	}
+	if int64(len(b)) > r.bytesLeft {
+		b = b[:r.bytesLeft]
+	}
+	n, err := r.r.Read(b)
+	r.bytesLeft -= int64(n)
+	if err == io.EOF {
+		err = io.ErrUnexpectedEOF
+	} else if r.bytesLeft == 0 && err == nil {
+		err = io.EOF
+	}
+	return n, err
+}
+
+// BackupStreamWriter writes a stream compatible with the BackupWrite Win32 API.
+type BackupStreamWriter struct {
+	w         io.Writer
+	bytesLeft int64
+}
+
+// NewBackupStreamWriter produces a BackupStreamWriter on top of an io.Writer.
+func NewBackupStreamWriter(w io.Writer) *BackupStreamWriter {
+	return &BackupStreamWriter{w, 0}
+}
+
+// WriteHeader writes the next backup stream header and prepares for calls to Write().
+func (w *BackupStreamWriter) WriteHeader(hdr *BackupHeader) error {
+	if w.bytesLeft != 0 {
+		return fmt.Errorf("missing %d bytes", w.bytesLeft)
+	}
+	name := utf16.Encode([]rune(hdr.Name))
+	wsi := win32StreamId{
+		StreamId:   hdr.Id,
+		Attributes: hdr.Attributes,
+		Size:       uint64(hdr.Size),
+		NameSize:   uint32(len(name) * 2),
+	}
+	if hdr.Id == BackupSparseBlock {
+		// Include space for the int64 block offset
+		wsi.Size += 8
+	}
+	if err := binary.Write(w.w, binary.LittleEndian, &wsi); err != nil {
+		return err
+	}
+	if len(name) != 0 {
+		if err := binary.Write(w.w, binary.LittleEndian, name); err != nil {
+			return err
+		}
+	}
+	if hdr.Id == BackupSparseBlock {
+		if err := binary.Write(w.w, binary.LittleEndian, hdr.Offset); err != nil {
+			return err
+		}
+	}
+	w.bytesLeft = hdr.Size
+	return nil
+}
+
+// Write writes to the current backup stream.
+func (w *BackupStreamWriter) Write(b []byte) (int, error) {
+	if w.bytesLeft < int64(len(b)) {
+		return 0, fmt.Errorf("too many bytes by %d", int64(len(b))-w.bytesLeft)
+	}
+	n, err := w.w.Write(b)
+	w.bytesLeft -= int64(n)
+	return n, err
+}
+
+// BackupFileReader provides an io.ReadCloser interface on top of the BackupRead Win32 API.
+type BackupFileReader struct {
+	f               *os.File
+	includeSecurity bool
+	ctx             uintptr
+}
+
+// NewBackupFileReader returns a new BackupFileReader from a file handle. If includeSecurity is true,
+// Read will attempt to read the security descriptor of the file.
+func NewBackupFileReader(f *os.File, includeSecurity bool) *BackupFileReader {
+	r := &BackupFileReader{f, includeSecurity, 0}
+	return r
+}
+
+// Read reads a backup stream from the file by calling the Win32 API BackupRead().
+func (r *BackupFileReader) Read(b []byte) (int, error) {
+	var bytesRead uint32
+	err := backupRead(syscall.Handle(r.f.Fd()), b, &bytesRead, false, r.includeSecurity, &r.ctx)
+	if err != nil {
+		return 0, &os.PathError{"BackupRead", r.f.Name(), err}
+	}
+	runtime.KeepAlive(r.f)
+	if bytesRead == 0 {
+		return 0, io.EOF
+	}
+	return int(bytesRead), nil
+}
+
+// Close frees Win32 resources associated with the BackupFileReader. It does not close
+// the underlying file.
+func (r *BackupFileReader) Close() error {
+	if r.ctx != 0 {
+		backupRead(syscall.Handle(r.f.Fd()), nil, nil, true, false, &r.ctx)
+		runtime.KeepAlive(r.f)
+		r.ctx = 0
+	}
+	return nil
+}
+
+// BackupFileWriter provides an io.WriteCloser interface on top of the BackupWrite Win32 API.
+type BackupFileWriter struct {
+	f               *os.File
+	includeSecurity bool
+	ctx             uintptr
+}
+
+// NewBackupFileWriter returns a new BackupFileWriter from a file handle. If includeSecurity is true,
+// Write() will attempt to restore the security descriptor from the stream.
+func NewBackupFileWriter(f *os.File, includeSecurity bool) *BackupFileWriter {
+	w := &BackupFileWriter{f, includeSecurity, 0}
+	return w
+}
+
+// Write restores a portion of the file using the provided backup stream.
+func (w *BackupFileWriter) Write(b []byte) (int, error) {
+	var bytesWritten uint32
+	err := backupWrite(syscall.Handle(w.f.Fd()), b, &bytesWritten, false, w.includeSecurity, &w.ctx)
+	if err != nil {
+		return 0, &os.PathError{"BackupWrite", w.f.Name(), err}
+	}
+	runtime.KeepAlive(w.f)
+	if int(bytesWritten) != len(b) {
+		return int(bytesWritten), errors.New("not all bytes could be written")
+	}
+	return len(b), nil
+}
+
+// Close frees Win32 resources associated with the BackupFileWriter. It does not
+// close the underlying file.
+func (w *BackupFileWriter) Close() error {
+	if w.ctx != 0 {
+		backupWrite(syscall.Handle(w.f.Fd()), nil, nil, true, false, &w.ctx)
+		runtime.KeepAlive(w.f)
+		w.ctx = 0
+	}
+	return nil
+}
+
+// OpenForBackup opens a file or directory, potentially skipping access checks if the backup
+// or restore privileges have been acquired.
+//
+// If the file opened was a directory, it cannot be used with Readdir().
+func OpenForBackup(path string, access uint32, share uint32, createmode uint32) (*os.File, error) {
+	winPath, err := syscall.UTF16FromString(path)
+	if err != nil {
+		return nil, err
+	}
+	h, err := syscall.CreateFile(&winPath[0], access, share, nil, createmode, syscall.FILE_FLAG_BACKUP_SEMANTICS|syscall.FILE_FLAG_OPEN_REPARSE_POINT, 0)
+	if err != nil {
+		err = &os.PathError{Op: "open", Path: path, Err: err}
+		return nil, err
+	}
+	return os.NewFile(uintptr(h), path), nil
+}
@@ -0,0 +1,137 @@
+package winio
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+)
+
+type fileFullEaInformation struct {
+	NextEntryOffset uint32
+	Flags           uint8
+	NameLength      uint8
+	ValueLength     uint16
+}
+
+var (
+	fileFullEaInformationSize = binary.Size(&fileFullEaInformation{})
+
+	errInvalidEaBuffer = errors.New("invalid extended attribute buffer")
+	errEaNameTooLarge  = errors.New("extended attribute name too large")
+	errEaValueTooLarge = errors.New("extended attribute value too large")
+)
+
+// ExtendedAttribute represents a single Windows EA.
+type ExtendedAttribute struct {
+	Name  string
+	Value []byte
+	Flags uint8
+}
+
+func parseEa(b []byte) (ea ExtendedAttribute, nb []byte, err error) {
+	var info fileFullEaInformation
+	err = binary.Read(bytes.NewReader(b), binary.LittleEndian, &info)
+	if err != nil {
+		err = errInvalidEaBuffer
+		return
+	}
+
+	nameOffset := fileFullEaInformationSize
+	nameLen := int(info.NameLength)
+	valueOffset := nameOffset + int(info.NameLength) + 1
+	valueLen := int(info.ValueLength)
+	nextOffset := int(info.NextEntryOffset)
+	if valueLen+valueOffset > len(b) || nextOffset < 0 || nextOffset > len(b) {
+		err = errInvalidEaBuffer
+		return
+	}
+
+	ea.Name = string(b[nameOffset : nameOffset+nameLen])
+	ea.Value = b[valueOffset : valueOffset+valueLen]
+	ea.Flags = info.Flags
+	if info.NextEntryOffset != 0 {
+		nb = b[info.NextEntryOffset:]
+	}
+	return
+}
+
+// DecodeExtendedAttributes decodes a list of EAs from a FILE_FULL_EA_INFORMATION
+// buffer retrieved from BackupRead, ZwQueryEaFile, etc.
+func DecodeExtendedAttributes(b []byte) (eas []ExtendedAttribute, err error) {
+	for len(b) != 0 {
+		ea, nb, err := parseEa(b)
+		if err != nil {
+			return nil, err
+		}
+
+		eas = append(eas, ea)
+		b = nb
+	}
+	return
+}
+
+func writeEa(buf *bytes.Buffer, ea *ExtendedAttribute, last bool) error {
+	if int(uint8(len(ea.Name))) != len(ea.Name) {
+		return errEaNameTooLarge
+	}
+	if int(uint16(len(ea.Value))) != len(ea.Value) {
+		return errEaValueTooLarge
+	}
+	entrySize := uint32(fileFullEaInformationSize + len(ea.Name) + 1 + len(ea.Value))
+	withPadding := (entrySize + 3) &^ 3
+	nextOffset := uint32(0)
+	if !last {
+		nextOffset = withPadding
+	}
+	info := fileFullEaInformation{
+		NextEntryOffset: nextOffset,
+		Flags:           ea.Flags,
+		NameLength:      uint8(len(ea.Name)),
+		ValueLength:     uint16(len(ea.Value)),
+	}
+
+	err := binary.Write(buf, binary.LittleEndian, &info)
+	if err != nil {
+		return err
+	}
+
+	_, err = buf.Write([]byte(ea.Name))
+	if err != nil {
+		return err
+	}
+
+	err = buf.WriteByte(0)
+	if err != nil {
+		return err
+	}
+
+	_, err = buf.Write(ea.Value)
+	if err != nil {
+		return err
+	}
+
+	_, err = buf.Write([]byte{0, 0, 0}[0 : withPadding-entrySize])
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// EncodeExtendedAttributes encodes a list of EAs into a FILE_FULL_EA_INFORMATION
+// buffer for use with BackupWrite, ZwSetEaFile, etc.
+func EncodeExtendedAttributes(eas []ExtendedAttribute) ([]byte, error) {
+	var buf bytes.Buffer
+	for i := range eas {
+		last := false
+		if i == len(eas)-1 {
+			last = true
+		}
+
+		err := writeEa(&buf, &eas[i], last)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return buf.Bytes(), nil
+}
@@ -0,0 +1,307 @@
+// +build windows
+
+package winio
+
+import (
+	"errors"
+	"io"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"syscall"
+	"time"
+)
+
+//sys cancelIoEx(file syscall.Handle, o *syscall.Overlapped) (err error) = CancelIoEx
+//sys createIoCompletionPort(file syscall.Handle, port syscall.Handle, key uintptr, threadCount uint32) (newport syscall.Handle, err error) = CreateIoCompletionPort
+//sys getQueuedCompletionStatus(port syscall.Handle, bytes *uint32, key *uintptr, o **ioOperation, timeout uint32) (err error) = GetQueuedCompletionStatus
+//sys setFileCompletionNotificationModes(h syscall.Handle, flags uint8) (err error) = SetFileCompletionNotificationModes
+
+type atomicBool int32
+
+func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
+func (b *atomicBool) setFalse()   { atomic.StoreInt32((*int32)(b), 0) }
+func (b *atomicBool) setTrue()    { atomic.StoreInt32((*int32)(b), 1) }
+func (b *atomicBool) swap(new bool) bool {
+	var newInt int32
+	if new {
+		newInt = 1
+	}
+	return atomic.SwapInt32((*int32)(b), newInt) == 1
+}
+
+const (
+	cFILE_SKIP_COMPLETION_PORT_ON_SUCCESS = 1
+	cFILE_SKIP_SET_EVENT_ON_HANDLE        = 2
+)
+
+var (
+	ErrFileClosed = errors.New("file has already been closed")
+	ErrTimeout    = &timeoutError{}
+)
+
+type timeoutError struct{}
+
+func (e *timeoutError) Error() string   { return "i/o timeout" }
+func (e *timeoutError) Timeout() bool   { return true }
+func (e *timeoutError) Temporary() bool { return true }
+
+type timeoutChan chan struct{}
+
+var ioInitOnce sync.Once
+var ioCompletionPort syscall.Handle
+
+// ioResult contains the result of an asynchronous IO operation
+type ioResult struct {
+	bytes uint32
+	err   error
+}
+
+// ioOperation represents an outstanding asynchronous Win32 IO
+type ioOperation struct {
+	o  syscall.Overlapped
+	ch chan ioResult
+}
+
+func initIo() {
+	h, err := createIoCompletionPort(syscall.InvalidHandle, 0, 0, 0xffffffff)
+	if err != nil {
+		panic(err)
+	}
+	ioCompletionPort = h
+	go ioCompletionProcessor(h)
+}
+
+// win32File implements Reader, Writer, and Closer on a Win32 handle without blocking in a syscall.
+// It takes ownership of this handle and will close it if it is garbage collected.
+type win32File struct {
+	handle        syscall.Handle
+	wg            sync.WaitGroup
+	wgLock        sync.RWMutex
+	closing       atomicBool
+	readDeadline  deadlineHandler
+	writeDeadline deadlineHandler
+}
+
+type deadlineHandler struct {
+	setLock     sync.Mutex
+	channel     timeoutChan
+	channelLock sync.RWMutex
+	timer       *time.Timer
+	timedout    atomicBool
+}
+
+// makeWin32File makes a new win32File from an existing file handle
+func makeWin32File(h syscall.Handle) (*win32File, error) {
+	f := &win32File{handle: h}
+	ioInitOnce.Do(initIo)
+	_, err := createIoCompletionPort(h, ioCompletionPort, 0, 0xffffffff)
+	if err != nil {
+		return nil, err
+	}
+	err = setFileCompletionNotificationModes(h, cFILE_SKIP_COMPLETION_PORT_ON_SUCCESS|cFILE_SKIP_SET_EVENT_ON_HANDLE)
+	if err != nil {
+		return nil, err
+	}
+	f.readDeadline.channel = make(timeoutChan)
+	f.writeDeadline.channel = make(timeoutChan)
+	return f, nil
+}
+
+func MakeOpenFile(h syscall.Handle) (io.ReadWriteCloser, error) {
+	return makeWin32File(h)
+}
+
+// closeHandle closes the resources associated with a Win32 handle
+func (f *win32File) closeHandle() {
+	f.wgLock.Lock()
+	// Atomically set that we are closing, releasing the resources only once.
+	if !f.closing.swap(true) {
+		f.wgLock.Unlock()
+		// cancel all IO and wait for it to complete
+		cancelIoEx(f.handle, nil)
+		f.wg.Wait()
+		// at this point, no new IO can start
+		syscall.Close(f.handle)
+		f.handle = 0
+	} else {
+		f.wgLock.Unlock()
+	}
+}
+
+// Close closes a win32File.
+func (f *win32File) Close() error {
+	f.closeHandle()
+	return nil
+}
+
+// prepareIo prepares for a new IO operation.
+// The caller must call f.wg.Done() when the IO is finished, prior to Close() returning.
+func (f *win32File) prepareIo() (*ioOperation, error) {
+	f.wgLock.RLock()
+	if f.closing.isSet() {
+		f.wgLock.RUnlock()
+		return nil, ErrFileClosed
+	}
+	f.wg.Add(1)
+	f.wgLock.RUnlock()
+	c := &ioOperation{}
+	c.ch = make(chan ioResult)
+	return c, nil
+}
+
+// ioCompletionProcessor processes completed async IOs forever
+func ioCompletionProcessor(h syscall.Handle) {
+	for {
+		var bytes uint32
+		var key uintptr
+		var op *ioOperation
+		err := getQueuedCompletionStatus(h, &bytes, &key, &op, syscall.INFINITE)
+		if op == nil {
+			panic(err)
+		}
+		op.ch <- ioResult{bytes, err}
+	}
+}
+
+// asyncIo processes the return value from ReadFile or WriteFile, blocking until
+// the operation has actually completed.
+func (f *win32File) asyncIo(c *ioOperation, d *deadlineHandler, bytes uint32, err error) (int, error) {
+	if err != syscall.ERROR_IO_PENDING {
+		return int(bytes), err
+	}
+
+	if f.closing.isSet() {
+		cancelIoEx(f.handle, &c.o)
+	}
+
+	var timeout timeoutChan
+	if d != nil {
+		d.channelLock.Lock()
+		timeout = d.channel
+		d.channelLock.Unlock()
+	}
+
+	var r ioResult
+	select {
+	case r = <-c.ch:
+		err = r.err
+		if err == syscall.ERROR_OPERATION_ABORTED {
+			if f.closing.isSet() {
+				err = ErrFileClosed
+			}
+		}
+	case <-timeout:
+		cancelIoEx(f.handle, &c.o)
+		r = <-c.ch
+		err = r.err
+		if err == syscall.ERROR_OPERATION_ABORTED {
+			err = ErrTimeout
+		}
+	}
+
+	// runtime.KeepAlive is needed, as c is passed via native
+	// code to ioCompletionProcessor, c must remain alive
+	// until the channel read is complete.
+	runtime.KeepAlive(c)
+	return int(r.bytes), err
+}
+
+// Read reads from a file handle.
+func (f *win32File) Read(b []byte) (int, error) {
+	c, err := f.prepareIo()
+	if err != nil {
+		return 0, err
+	}
+	defer f.wg.Done()
+
+	if f.readDeadline.timedout.isSet() {
+		return 0, ErrTimeout
+	}
+
+	var bytes uint32
+	err = syscall.ReadFile(f.handle, b, &bytes, &c.o)
+	n, err := f.asyncIo(c, &f.readDeadline, bytes, err)
+	runtime.KeepAlive(b)
+
+	// Handle EOF conditions.
+	if err == nil && n == 0 && len(b) != 0 {
+		return 0, io.EOF
+	} else if err == syscall.ERROR_BROKEN_PIPE {
+		return 0, io.EOF
+	} else {
+		return n, err
+	}
+}
+
+// Write writes to a file handle.
+func (f *win32File) Write(b []byte) (int, error) {
+	c, err := f.prepareIo()
+	if err != nil {
+		return 0, err
+	}
+	defer f.wg.Done()
+
+	if f.writeDeadline.timedout.isSet() {
+		return 0, ErrTimeout
+	}
+
+	var bytes uint32
+	err = syscall.WriteFile(f.handle, b, &bytes, &c.o)
+	n, err := f.asyncIo(c, &f.writeDeadline, bytes, err)
+	runtime.KeepAlive(b)
+	return n, err
+}
+
+func (f *win32File) SetReadDeadline(deadline time.Time) error {
+	return f.readDeadline.set(deadline)
+}
+
+func (f *win32File) SetWriteDeadline(deadline time.Time) error {
+	return f.writeDeadline.set(deadline)
+}
+
+func (f *win32File) Flush() error {
+	return syscall.FlushFileBuffers(f.handle)
+}
+
+func (d *deadlineHandler) set(deadline time.Time) error {
+	d.setLock.Lock()
+	defer d.setLock.Unlock()
+
+	if d.timer != nil {
+		if !d.timer.Stop() {
+			<-d.channel
+		}
+		d.timer = nil
+	}
+	d.timedout.setFalse()
+
+	select {
+	case <-d.channel:
+		d.channelLock.Lock()
+		d.channel = make(chan struct{})
+		d.channelLock.Unlock()
+	default:
+	}
+
+	if deadline.IsZero() {
+		return nil
+	}
+
+	timeoutIO := func() {
+		d.timedout.setTrue()
+		close(d.channel)
+	}
+
+	now := time.Now()
+	duration := deadline.Sub(now)
+	if deadline.After(now) {
+		// Deadline is in the future, set a timer to wait
+		d.timer = time.AfterFunc(duration, timeoutIO)
+	} else {
+		// Deadline is in the past. Cancel all pending IO now.
+		timeoutIO()
+	}
+	return nil
+}
@@ -0,0 +1,60 @@
+// +build windows
+
+package winio
+
+import (
+	"os"
+	"runtime"
+	"syscall"
+	"unsafe"
+)
+
+//sys getFileInformationByHandleEx(h syscall.Handle, class uint32, buffer *byte, size uint32) (err error) = GetFileInformationByHandleEx
+//sys setFileInformationByHandle(h syscall.Handle, class uint32, buffer *byte, size uint32) (err error) = SetFileInformationByHandle
+
+const (
+	fileBasicInfo = 0
+	fileIDInfo    = 0x12
+)
+
+// FileBasicInfo contains file access time and file attributes information.
+type FileBasicInfo struct {
+	CreationTime, LastAccessTime, LastWriteTime, ChangeTime syscall.Filetime
+	FileAttributes                                          uintptr // includes padding
+}
+
+// GetFileBasicInfo retrieves times and attributes for a file.
+func GetFileBasicInfo(f *os.File) (*FileBasicInfo, error) {
+	bi := &FileBasicInfo{}
+	if err := getFileInformationByHandleEx(syscall.Handle(f.Fd()), fileBasicInfo, (*byte)(unsafe.Pointer(bi)), uint32(unsafe.Sizeof(*bi))); err != nil {
+		return nil, &os.PathError{Op: "GetFileInformationByHandleEx", Path: f.Name(), Err: err}
+	}
+	runtime.KeepAlive(f)
+	return bi, nil
+}
+
+// SetFileBasicInfo sets times and attributes for a file.
+func SetFileBasicInfo(f *os.File, bi *FileBasicInfo) error {
+	if err := setFileInformationByHandle(syscall.Handle(f.Fd()), fileBasicInfo, (*byte)(unsafe.Pointer(bi)), uint32(unsafe.Sizeof(*bi))); err != nil {
+		return &os.PathError{Op: "SetFileInformationByHandle", Path: f.Name(), Err: err}
+	}
+	runtime.KeepAlive(f)
+	return nil
+}
+
+// FileIDInfo contains the volume serial number and file ID for a file. This pair should be
+// unique on a system.
+type FileIDInfo struct {
+	VolumeSerialNumber uint64
+	FileID             [16]byte
+}
+
+// GetFileID retrieves the unique (volume, file ID) pair for a file.
+func GetFileID(f *os.File) (*FileIDInfo, error) {
+	fileID := &FileIDInfo{}
+	if err := getFileInformationByHandleEx(syscall.Handle(f.Fd()), fileIDInfo, (*byte)(unsafe.Pointer(fileID)), uint32(unsafe.Sizeof(*fileID))); err != nil {
+		return nil, &os.PathError{Op: "GetFileInformationByHandleEx", Path: f.Name(), Err: err}
+	}
+	runtime.KeepAlive(f)
+	return fileID, nil
+}
@@ -0,0 +1,424 @@
+// +build windows
+
+package winio
+
+import (
+	"errors"
+	"io"
+	"net"
+	"os"
+	"syscall"
+	"time"
+	"unsafe"
+)
+
+//sys connectNamedPipe(pipe syscall.Handle, o *syscall.Overlapped) (err error) = ConnectNamedPipe
+//sys createNamedPipe(name string, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error)  [failretval==syscall.InvalidHandle] = CreateNamedPipeW
+//sys createFile(name string, access uint32, mode uint32, sa *syscall.SecurityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateFileW
+//sys waitNamedPipe(name string, timeout uint32) (err error) = WaitNamedPipeW
+//sys getNamedPipeInfo(pipe syscall.Handle, flags *uint32, outSize *uint32, inSize *uint32, maxInstances *uint32) (err error) = GetNamedPipeInfo
+//sys getNamedPipeHandleState(pipe syscall.Handle, state *uint32, curInstances *uint32, maxCollectionCount *uint32, collectDataTimeout *uint32, userName *uint16, maxUserNameSize uint32) (err error) = GetNamedPipeHandleStateW
+//sys localAlloc(uFlags uint32, length uint32) (ptr uintptr) = LocalAlloc
+
+const (
+	cERROR_PIPE_BUSY      = syscall.Errno(231)
+	cERROR_NO_DATA        = syscall.Errno(232)
+	cERROR_PIPE_CONNECTED = syscall.Errno(535)
+	cERROR_SEM_TIMEOUT    = syscall.Errno(121)
+
+	cPIPE_ACCESS_DUPLEX            = 0x3
+	cFILE_FLAG_FIRST_PIPE_INSTANCE = 0x80000
+	cSECURITY_SQOS_PRESENT         = 0x100000
+	cSECURITY_ANONYMOUS            = 0
+
+	cPIPE_REJECT_REMOTE_CLIENTS = 0x8
+
+	cPIPE_UNLIMITED_INSTANCES = 255
+
+	cNMPWAIT_USE_DEFAULT_WAIT = 0
+	cNMPWAIT_NOWAIT           = 1
+
+	cPIPE_TYPE_MESSAGE = 4
+
+	cPIPE_READMODE_MESSAGE = 2
+)
+
+var (
+	// ErrPipeListenerClosed is returned for pipe operations on listeners that have been closed.
+	// This error should match net.errClosing since docker takes a dependency on its text.
+	ErrPipeListenerClosed = errors.New("use of closed network connection")
+
+	errPipeWriteClosed = errors.New("pipe has been closed for write")
+)
+
+type win32Pipe struct {
+	*win32File
+	path string
+}
+
+type win32MessageBytePipe struct {
+	win32Pipe
+	writeClosed bool
+	readEOF     bool
+}
+
+type pipeAddress string
+
+func (f *win32Pipe) LocalAddr() net.Addr {
+	return pipeAddress(f.path)
+}
+
+func (f *win32Pipe) RemoteAddr() net.Addr {
+	return pipeAddress(f.path)
+}
+
+func (f *win32Pipe) SetDeadline(t time.Time) error {
+	f.SetReadDeadline(t)
+	f.SetWriteDeadline(t)
+	return nil
+}
+
+// CloseWrite closes the write side of a message pipe in byte mode.
+func (f *win32MessageBytePipe) CloseWrite() error {
+	if f.writeClosed {
+		return errPipeWriteClosed
+	}
+	err := f.win32File.Flush()
+	if err != nil {
+		return err
+	}
+	_, err = f.win32File.Write(nil)
+	if err != nil {
+		return err
+	}
+	f.writeClosed = true
+	return nil
+}
+
+// Write writes bytes to a message pipe in byte mode. Zero-byte writes are ignored, since
+// they are used to implement CloseWrite().
+func (f *win32MessageBytePipe) Write(b []byte) (int, error) {
+	if f.writeClosed {
+		return 0, errPipeWriteClosed
+	}
+	if len(b) == 0 {
+		return 0, nil
+	}
+	return f.win32File.Write(b)
+}
+
+// Read reads bytes from a message pipe in byte mode. A read of a zero-byte message on a message
+// mode pipe will return io.EOF, as will all subsequent reads.
+func (f *win32MessageBytePipe) Read(b []byte) (int, error) {
+	if f.readEOF {
+		return 0, io.EOF
+	}
+	n, err := f.win32File.Read(b)
+	if err == io.EOF {
+		// If this was the result of a zero-byte read, then
+		// it is possible that the read was due to a zero-size
+		// message. Since we are simulating CloseWrite with a
+		// zero-byte message, ensure that all future Read() calls
+		// also return EOF.
+		f.readEOF = true
+	}
+	return n, err
+}
+
+func (s pipeAddress) Network() string {
+	return "pipe"
+}
+
+func (s pipeAddress) String() string {
+	return string(s)
+}
+
+// DialPipe connects to a named pipe by path, timing out if the connection
+// takes longer than the specified duration. If timeout is nil, then the timeout
+// is the default timeout established by the pipe server.
+func DialPipe(path string, timeout *time.Duration) (net.Conn, error) {
+	var absTimeout time.Time
+	if timeout != nil {
+		absTimeout = time.Now().Add(*timeout)
+	}
+	var err error
+	var h syscall.Handle
+	for {
+		h, err = createFile(path, syscall.GENERIC_READ|syscall.GENERIC_WRITE, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_OVERLAPPED|cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0)
+		if err != cERROR_PIPE_BUSY {
+			break
+		}
+		now := time.Now()
+		var ms uint32
+		if absTimeout.IsZero() {
+			ms = cNMPWAIT_USE_DEFAULT_WAIT
+		} else if now.After(absTimeout) {
+			ms = cNMPWAIT_NOWAIT
+		} else {
+			ms = uint32(absTimeout.Sub(now).Nanoseconds() / 1000 / 1000)
+		}
+		err = waitNamedPipe(path, ms)
+		if err != nil {
+			if err == cERROR_SEM_TIMEOUT {
+				return nil, ErrTimeout
+			}
+			break
+		}
+	}
+	if err != nil {
+		return nil, &os.PathError{Op: "open", Path: path, Err: err}
+	}
+
+	var flags uint32
+	err = getNamedPipeInfo(h, &flags, nil, nil, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var state uint32
+	err = getNamedPipeHandleState(h, &state, nil, nil, nil, nil, 0)
+	if err != nil {
+		return nil, err
+	}
+
+	if state&cPIPE_READMODE_MESSAGE != 0 {
+		return nil, &os.PathError{Op: "open", Path: path, Err: errors.New("message readmode pipes not supported")}
+	}
+
+	f, err := makeWin32File(h)
+	if err != nil {
+		syscall.Close(h)
+		return nil, err
+	}
+
+	// If the pipe is in message mode, return a message byte pipe, which
+	// supports CloseWrite().
+	if flags&cPIPE_TYPE_MESSAGE != 0 {
+		return &win32MessageBytePipe{
+			win32Pipe: win32Pipe{win32File: f, path: path},
+		}, nil
+	}
+	return &win32Pipe{win32File: f, path: path}, nil
+}
+
+type acceptResponse struct {
+	f   *win32File
+	err error
+}
+
+type win32PipeListener struct {
+	firstHandle        syscall.Handle
+	path               string
+	securityDescriptor []byte
+	config             PipeConfig
+	acceptCh           chan (chan acceptResponse)
+	closeCh            chan int
+	doneCh             chan int
+}
+
+func makeServerPipeHandle(path string, securityDescriptor []byte, c *PipeConfig, first bool) (syscall.Handle, error) {
+	var flags uint32 = cPIPE_ACCESS_DUPLEX | syscall.FILE_FLAG_OVERLAPPED
+	if first {
+		flags |= cFILE_FLAG_FIRST_PIPE_INSTANCE
+	}
+
+	var mode uint32 = cPIPE_REJECT_REMOTE_CLIENTS
+	if c.MessageMode {
+		mode |= cPIPE_TYPE_MESSAGE
+	}
+
+	sa := &syscall.SecurityAttributes{}
+	sa.Length = uint32(unsafe.Sizeof(*sa))
+	if securityDescriptor != nil {
+		len := uint32(len(securityDescriptor))
+		sa.SecurityDescriptor = localAlloc(0, len)
+		defer localFree(sa.SecurityDescriptor)
+		copy((*[0xffff]byte)(unsafe.Pointer(sa.SecurityDescriptor))[:], securityDescriptor)
+	}
+	h, err := createNamedPipe(path, flags, mode, cPIPE_UNLIMITED_INSTANCES, uint32(c.OutputBufferSize), uint32(c.InputBufferSize), 0, sa)
+	if err != nil {
+		return 0, &os.PathError{Op: "open", Path: path, Err: err}
+	}
+	return h, nil
+}
+
+func (l *win32PipeListener) makeServerPipe() (*win32File, error) {
+	h, err := makeServerPipeHandle(l.path, l.securityDescriptor, &l.config, false)
+	if err != nil {
+		return nil, err
+	}
+	f, err := makeWin32File(h)
+	if err != nil {
+		syscall.Close(h)
+		return nil, err
+	}
+	return f, nil
+}
+
+func (l *win32PipeListener) makeConnectedServerPipe() (*win32File, error) {
+	p, err := l.makeServerPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	// Wait for the client to connect.
+	ch := make(chan error)
+	go func(p *win32File) {
+		ch <- connectPipe(p)
+	}(p)
+
+	select {
+	case err = <-ch:
+		if err != nil {
+			p.Close()
+			p = nil
+		}
+	case <-l.closeCh:
+		// Abort the connect request by closing the handle.
+		p.Close()
+		p = nil
+		err = <-ch
+		if err == nil || err == ErrFileClosed {
+			err = ErrPipeListenerClosed
+		}
+	}
+	return p, err
+}
+
+func (l *win32PipeListener) listenerRoutine() {
+	closed := false
+	for !closed {
+		select {
+		case <-l.closeCh:
+			closed = true
+		case responseCh := <-l.acceptCh:
+			var (
+				p   *win32File
+				err error
+			)
+			for {
+				p, err = l.makeConnectedServerPipe()
+				// If the connection was immediately closed by the client, try
+				// again.
+				if err != cERROR_NO_DATA {
+					break
+				}
+			}
+			responseCh <- acceptResponse{p, err}
+			closed = err == ErrPipeListenerClosed
+		}
+	}
+	syscall.Close(l.firstHandle)
+	l.firstHandle = 0
+	// Notify Close() and Accept() callers that the handle has been closed.
+	close(l.doneCh)
+}
+
+// PipeConfig contain configuration for the pipe listener.
+type PipeConfig struct {
+	// SecurityDescriptor contains a Windows security descriptor in SDDL format.
+	SecurityDescriptor string
+
+	// MessageMode determines whether the pipe is in byte or message mode. In either
+	// case the pipe is read in byte mode by default. The only practical difference in
+	// this implementation is that CloseWrite() is only supported for message mode pipes;
+	// CloseWrite() is implemented as a zero-byte write, but zero-byte writes are only
+	// transferred to the reader (and returned as io.EOF in this implementation)
+	// when the pipe is in message mode.
+	MessageMode bool
+
+	// InputBufferSize specifies the size the input buffer, in bytes.
+	InputBufferSize int32
+
+	// OutputBufferSize specifies the size the input buffer, in bytes.
+	OutputBufferSize int32
+}
+
+// ListenPipe creates a listener on a Windows named pipe path, e.g. \\.\pipe\mypipe.
+// The pipe must not already exist.
+func ListenPipe(path string, c *PipeConfig) (net.Listener, error) {
+	var (
+		sd  []byte
+		err error
+	)
+	if c == nil {
+		c = &PipeConfig{}
+	}
+	if c.SecurityDescriptor != "" {
+		sd, err = SddlToSecurityDescriptor(c.SecurityDescriptor)
+		if err != nil {
+			return nil, err
+		}
+	}
+	h, err := makeServerPipeHandle(path, sd, c, true)
+	if err != nil {
+		return nil, err
+	}
+	// Immediately open and then close a client handle so that the named pipe is
+	// created but not currently accepting connections.
+	h2, err := createFile(path, 0, 0, nil, syscall.OPEN_EXISTING, cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0)
+	if err != nil {
+		syscall.Close(h)
+		return nil, err
+	}
+	syscall.Close(h2)
+	l := &win32PipeListener{
+		firstHandle:        h,
+		path:               path,
+		securityDescriptor: sd,
+		config:             *c,
+		acceptCh:           make(chan (chan acceptResponse)),
+		closeCh:            make(chan int),
+		doneCh:             make(chan int),
+	}
+	go l.listenerRoutine()
+	return l, nil
+}
+
+func connectPipe(p *win32File) error {
+	c, err := p.prepareIo()
+	if err != nil {
+		return err
+	}
+	defer p.wg.Done()
+
+	err = connectNamedPipe(p.handle, &c.o)
+	_, err = p.asyncIo(c, nil, 0, err)
+	if err != nil && err != cERROR_PIPE_CONNECTED {
+		return err
+	}
+	return nil
+}
+
+func (l *win32PipeListener) Accept() (net.Conn, error) {
+	ch := make(chan acceptResponse)
+	select {
+	case l.acceptCh <- ch:
+		response := <-ch
+		err := response.err
+		if err != nil {
+			return nil, err
+		}
+		if l.config.MessageMode {
+			return &win32MessageBytePipe{
+				win32Pipe: win32Pipe{win32File: response.f, path: l.path},
+			}, nil
+		}
+		return &win32Pipe{win32File: response.f, path: l.path}, nil
+	case <-l.doneCh:
+		return nil, ErrPipeListenerClosed
+	}
+}
+
+func (l *win32PipeListener) Close() error {
+	select {
+	case l.closeCh <- 1:
+		<-l.doneCh
+	case <-l.doneCh:
+	}
+	return nil
+}
+
+func (l *win32PipeListener) Addr() net.Addr {
+	return pipeAddress(l.path)
+}
@@ -0,0 +1,202 @@
+// +build windows
+
+package winio
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"runtime"
+	"sync"
+	"syscall"
+	"unicode/utf16"
+
+	"golang.org/x/sys/windows"
+)
+
+//sys adjustTokenPrivileges(token windows.Token, releaseAll bool, input *byte, outputSize uint32, output *byte, requiredSize *uint32) (success bool, err error) [true] = advapi32.AdjustTokenPrivileges
+//sys impersonateSelf(level uint32) (err error) = advapi32.ImpersonateSelf
+//sys revertToSelf() (err error) = advapi32.RevertToSelf
+//sys openThreadToken(thread syscall.Handle, accessMask uint32, openAsSelf bool, token *windows.Token) (err error) = advapi32.OpenThreadToken
+//sys getCurrentThread() (h syscall.Handle) = GetCurrentThread
+//sys lookupPrivilegeValue(systemName string, name string, luid *uint64) (err error) = advapi32.LookupPrivilegeValueW
+//sys lookupPrivilegeName(systemName string, luid *uint64, buffer *uint16, size *uint32) (err error) = advapi32.LookupPrivilegeNameW
+//sys lookupPrivilegeDisplayName(systemName string, name *uint16, buffer *uint16, size *uint32, languageId *uint32) (err error) = advapi32.LookupPrivilegeDisplayNameW
+
+const (
+	SE_PRIVILEGE_ENABLED = 2
+
+	ERROR_NOT_ALL_ASSIGNED syscall.Errno = 1300
+
+	SeBackupPrivilege  = "SeBackupPrivilege"
+	SeRestorePrivilege = "SeRestorePrivilege"
+)
+
+const (
+	securityAnonymous = iota
+	securityIdentification
+	securityImpersonation
+	securityDelegation
+)
+
+var (
+	privNames     = make(map[string]uint64)
+	privNameMutex sync.Mutex
+)
+
+// PrivilegeError represents an error enabling privileges.
+type PrivilegeError struct {
+	privileges []uint64
+}
+
+func (e *PrivilegeError) Error() string {
+	s := ""
+	if len(e.privileges) > 1 {
+		s = "Could not enable privileges "
+	} else {
+		s = "Could not enable privilege "
+	}
+	for i, p := range e.privileges {
+		if i != 0 {
+			s += ", "
+		}
+		s += `"`
+		s += getPrivilegeName(p)
+		s += `"`
+	}
+	return s
+}
+
+// RunWithPrivilege enables a single privilege for a function call.
+func RunWithPrivilege(name string, fn func() error) error {
+	return RunWithPrivileges([]string{name}, fn)
+}
+
+// RunWithPrivileges enables privileges for a function call.
+func RunWithPrivileges(names []string, fn func() error) error {
+	privileges, err := mapPrivileges(names)
+	if err != nil {
+		return err
+	}
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+	token, err := newThreadToken()
+	if err != nil {
+		return err
+	}
+	defer releaseThreadToken(token)
+	err = adjustPrivileges(token, privileges, SE_PRIVILEGE_ENABLED)
+	if err != nil {
+		return err
+	}
+	return fn()
+}
+
+func mapPrivileges(names []string) ([]uint64, error) {
+	var privileges []uint64
+	privNameMutex.Lock()
+	defer privNameMutex.Unlock()
+	for _, name := range names {
+		p, ok := privNames[name]
+		if !ok {
+			err := lookupPrivilegeValue("", name, &p)
+			if err != nil {
+				return nil, err
+			}
+			privNames[name] = p
+		}
+		privileges = append(privileges, p)
+	}
+	return privileges, nil
+}
+
+// EnableProcessPrivileges enables privileges globally for the process.
+func EnableProcessPrivileges(names []string) error {
+	return enableDisableProcessPrivilege(names, SE_PRIVILEGE_ENABLED)
+}
+
+// DisableProcessPrivileges disables privileges globally for the process.
+func DisableProcessPrivileges(names []string) error {
+	return enableDisableProcessPrivilege(names, 0)
+}
+
+func enableDisableProcessPrivilege(names []string, action uint32) error {
+	privileges, err := mapPrivileges(names)
+	if err != nil {
+		return err
+	}
+
+	p, _ := windows.GetCurrentProcess()
+	var token windows.Token
+	err = windows.OpenProcessToken(p, windows.TOKEN_ADJUST_PRIVILEGES|windows.TOKEN_QUERY, &token)
+	if err != nil {
+		return err
+	}
+
+	defer token.Close()
+	return adjustPrivileges(token, privileges, action)
+}
+
+func adjustPrivileges(token windows.Token, privileges []uint64, action uint32) error {
+	var b bytes.Buffer
+	binary.Write(&b, binary.LittleEndian, uint32(len(privileges)))
+	for _, p := range privileges {
+		binary.Write(&b, binary.LittleEndian, p)
+		binary.Write(&b, binary.LittleEndian, action)
+	}
+	prevState := make([]byte, b.Len())
+	reqSize := uint32(0)
+	success, err := adjustTokenPrivileges(token, false, &b.Bytes()[0], uint32(len(prevState)), &prevState[0], &reqSize)
+	if !success {
+		return err
+	}
+	if err == ERROR_NOT_ALL_ASSIGNED {
+		return &PrivilegeError{privileges}
+	}
+	return nil
+}
+
+func getPrivilegeName(luid uint64) string {
+	var nameBuffer [256]uint16
+	bufSize := uint32(len(nameBuffer))
+	err := lookupPrivilegeName("", &luid, &nameBuffer[0], &bufSize)
+	if err != nil {
+		return fmt.Sprintf("<unknown privilege %d>", luid)
+	}
+
+	var displayNameBuffer [256]uint16
+	displayBufSize := uint32(len(displayNameBuffer))
+	var langID uint32
+	err = lookupPrivilegeDisplayName("", &nameBuffer[0], &displayNameBuffer[0], &displayBufSize, &langID)
+	if err != nil {
+		return fmt.Sprintf("<unknown privilege %s>", string(utf16.Decode(nameBuffer[:bufSize])))
+	}
+
+	return string(utf16.Decode(displayNameBuffer[:displayBufSize]))
+}
+
+func newThreadToken() (windows.Token, error) {
+	err := impersonateSelf(securityImpersonation)
+	if err != nil {
+		return 0, err
+	}
+
+	var token windows.Token
+	err = openThreadToken(getCurrentThread(), syscall.TOKEN_ADJUST_PRIVILEGES|syscall.TOKEN_QUERY, false, &token)
+	if err != nil {
+		rerr := revertToSelf()
+		if rerr != nil {
+			panic(rerr)
+		}
+		return 0, err
+	}
+	return token, nil
+}
+
+func releaseThreadToken(h windows.Token) {
+	err := revertToSelf()
+	if err != nil {
+		panic(err)
+	}
+	h.Close()
+}
@@ -0,0 +1,128 @@
+package winio
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"strings"
+	"unicode/utf16"
+	"unsafe"
+)
+
+const (
+	reparseTagMountPoint = 0xA0000003
+	reparseTagSymlink    = 0xA000000C
+)
+
+type reparseDataBuffer struct {
+	ReparseTag           uint32
+	ReparseDataLength    uint16
+	Reserved             uint16
+	SubstituteNameOffset uint16
+	SubstituteNameLength uint16
+	PrintNameOffset      uint16
+	PrintNameLength      uint16
+}
+
+// ReparsePoint describes a Win32 symlink or mount point.
+type ReparsePoint struct {
+	Target       string
+	IsMountPoint bool
+}
+
+// UnsupportedReparsePointError is returned when trying to decode a non-symlink or
+// mount point reparse point.
+type UnsupportedReparsePointError struct {
+	Tag uint32
+}
+
+func (e *UnsupportedReparsePointError) Error() string {
+	return fmt.Sprintf("unsupported reparse point %x", e.Tag)
+}
+
+// DecodeReparsePoint decodes a Win32 REPARSE_DATA_BUFFER structure containing either a symlink
+// or a mount point.
+func DecodeReparsePoint(b []byte) (*ReparsePoint, error) {
+	tag := binary.LittleEndian.Uint32(b[0:4])
+	return DecodeReparsePointData(tag, b[8:])
+}
+
+func DecodeReparsePointData(tag uint32, b []byte) (*ReparsePoint, error) {
+	isMountPoint := false
+	switch tag {
+	case reparseTagMountPoint:
+		isMountPoint = true
+	case reparseTagSymlink:
+	default:
+		return nil, &UnsupportedReparsePointError{tag}
+	}
+	nameOffset := 8 + binary.LittleEndian.Uint16(b[4:6])
+	if !isMountPoint {
+		nameOffset += 4
+	}
+	nameLength := binary.LittleEndian.Uint16(b[6:8])
+	name := make([]uint16, nameLength/2)
+	err := binary.Read(bytes.NewReader(b[nameOffset:nameOffset+nameLength]), binary.LittleEndian, &name)
+	if err != nil {
+		return nil, err
+	}
+	return &ReparsePoint{string(utf16.Decode(name)), isMountPoint}, nil
+}
+
+func isDriveLetter(c byte) bool {
+	return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
+}
+
+// EncodeReparsePoint encodes a Win32 REPARSE_DATA_BUFFER structure describing a symlink or
+// mount point.
+func EncodeReparsePoint(rp *ReparsePoint) []byte {
+	// Generate an NT path and determine if this is a relative path.
+	var ntTarget string
+	relative := false
+	if strings.HasPrefix(rp.Target, `\\?\`) {
+		ntTarget = `\??\` + rp.Target[4:]
+	} else if strings.HasPrefix(rp.Target, `\\`) {
+		ntTarget = `\??\UNC\` + rp.Target[2:]
+	} else if len(rp.Target) >= 2 && isDriveLetter(rp.Target[0]) && rp.Target[1] == ':' {
+		ntTarget = `\??\` + rp.Target
+	} else {
+		ntTarget = rp.Target
+		relative = true
+	}
+
+	// The paths must be NUL-terminated even though they are counted strings.
+	target16 := utf16.Encode([]rune(rp.Target + "\x00"))
+	ntTarget16 := utf16.Encode([]rune(ntTarget + "\x00"))
+
+	size := int(unsafe.Sizeof(reparseDataBuffer{})) - 8
+	size += len(ntTarget16)*2 + len(target16)*2
+
+	tag := uint32(reparseTagMountPoint)
+	if !rp.IsMountPoint {
+		tag = reparseTagSymlink
+		size += 4 // Add room for symlink flags
+	}
+
+	data := reparseDataBuffer{
+		ReparseTag:           tag,
+		ReparseDataLength:    uint16(size),
+		SubstituteNameOffset: 0,
+		SubstituteNameLength: uint16((len(ntTarget16) - 1) * 2),
+		PrintNameOffset:      uint16(len(ntTarget16) * 2),
+		PrintNameLength:      uint16((len(target16) - 1) * 2),
+	}
+
+	var b bytes.Buffer
+	binary.Write(&b, binary.LittleEndian, &data)
+	if !rp.IsMountPoint {
+		flags := uint32(0)
+		if relative {
+			flags |= 1
+		}
+		binary.Write(&b, binary.LittleEndian, flags)
+	}
+
+	binary.Write(&b, binary.LittleEndian, ntTarget16)
+	binary.Write(&b, binary.LittleEndian, target16)
+	return b.Bytes()
+}
@@ -0,0 +1,98 @@
+// +build windows
+
+package winio
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+//sys lookupAccountName(systemName *uint16, accountName string, sid *byte, sidSize *uint32, refDomain *uint16, refDomainSize *uint32, sidNameUse *uint32) (err error) = advapi32.LookupAccountNameW
+//sys convertSidToStringSid(sid *byte, str **uint16) (err error) = advapi32.ConvertSidToStringSidW
+//sys convertStringSecurityDescriptorToSecurityDescriptor(str string, revision uint32, sd *uintptr, size *uint32) (err error) = advapi32.ConvertStringSecurityDescriptorToSecurityDescriptorW
+//sys convertSecurityDescriptorToStringSecurityDescriptor(sd *byte, revision uint32, secInfo uint32, sddl **uint16, sddlSize *uint32) (err error) = advapi32.ConvertSecurityDescriptorToStringSecurityDescriptorW
+//sys localFree(mem uintptr) = LocalFree
+//sys getSecurityDescriptorLength(sd uintptr) (len uint32) = advapi32.GetSecurityDescriptorLength
+
+const (
+	cERROR_NONE_MAPPED = syscall.Errno(1332)
+)
+
+type AccountLookupError struct {
+	Name string
+	Err  error
+}
+
+func (e *AccountLookupError) Error() string {
+	if e.Name == "" {
+		return "lookup account: empty account name specified"
+	}
+	var s string
+	switch e.Err {
+	case cERROR_NONE_MAPPED:
+		s = "not found"
+	default:
+		s = e.Err.Error()
+	}
+	return "lookup account " + e.Name + ": " + s
+}
+
+type SddlConversionError struct {
+	Sddl string
+	Err  error
+}
+
+func (e *SddlConversionError) Error() string {
+	return "convert " + e.Sddl + ": " + e.Err.Error()
+}
+
+// LookupSidByName looks up the SID of an account by name
+func LookupSidByName(name string) (sid string, err error) {
+	if name == "" {
+		return "", &AccountLookupError{name, cERROR_NONE_MAPPED}
+	}
+
+	var sidSize, sidNameUse, refDomainSize uint32
+	err = lookupAccountName(nil, name, nil, &sidSize, nil, &refDomainSize, &sidNameUse)
+	if err != nil && err != syscall.ERROR_INSUFFICIENT_BUFFER {
+		return "", &AccountLookupError{name, err}
+	}
+	sidBuffer := make([]byte, sidSize)
+	refDomainBuffer := make([]uint16, refDomainSize)
+	err = lookupAccountName(nil, name, &sidBuffer[0], &sidSize, &refDomainBuffer[0], &refDomainSize, &sidNameUse)
+	if err != nil {
+		return "", &AccountLookupError{name, err}
+	}
+	var strBuffer *uint16
+	err = convertSidToStringSid(&sidBuffer[0], &strBuffer)
+	if err != nil {
+		return "", &AccountLookupError{name, err}
+	}
+	sid = syscall.UTF16ToString((*[0xffff]uint16)(unsafe.Pointer(strBuffer))[:])
+	localFree(uintptr(unsafe.Pointer(strBuffer)))
+	return sid, nil
+}
+
+func SddlToSecurityDescriptor(sddl string) ([]byte, error) {
+	var sdBuffer uintptr
+	err := convertStringSecurityDescriptorToSecurityDescriptor(sddl, 1, &sdBuffer, nil)
+	if err != nil {
+		return nil, &SddlConversionError{sddl, err}
+	}
+	defer localFree(sdBuffer)
+	sd := make([]byte, getSecurityDescriptorLength(sdBuffer))
+	copy(sd, (*[0xffff]byte)(unsafe.Pointer(sdBuffer))[:len(sd)])
+	return sd, nil
+}
+
+func SecurityDescriptorToSddl(sd []byte) (string, error) {
+	var sddl *uint16
+	// The returned string length seems to including an aribtrary number of terminating NULs.
+	// Don't use it.
+	err := convertSecurityDescriptorToStringSecurityDescriptor(&sd[0], 1, 0xff, &sddl, nil)
+	if err != nil {
+		return "", err
+	}
+	defer localFree(uintptr(unsafe.Pointer(sddl)))
+	return syscall.UTF16ToString((*[0xffff]uint16)(unsafe.Pointer(sddl))[:]), nil
+}
@@ -0,0 +1,3 @@
+package winio
+
+//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go file.go pipe.go sd.go fileinfo.go privilege.go backup.go
@@ -0,0 +1,520 @@
+// MACHINE GENERATED BY 'go generate' COMMAND; DO NOT EDIT
+
+package winio
+
+import (
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var _ unsafe.Pointer
+
+// Do the interface allocations only once for common
+// Errno values.
+const (
+	errnoERROR_IO_PENDING = 997
+)
+
+var (
+	errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case errnoERROR_IO_PENDING:
+		return errERROR_IO_PENDING
+	}
+	// TODO: add more here, after collecting data on the common
+	// error values see on Windows. (perhaps when running
+	// all.bat?)
+	return e
+}
+
+var (
+	modkernel32 = windows.NewLazySystemDLL("kernel32.dll")
+	modadvapi32 = windows.NewLazySystemDLL("advapi32.dll")
+
+	procCancelIoEx                                           = modkernel32.NewProc("CancelIoEx")
+	procCreateIoCompletionPort                               = modkernel32.NewProc("CreateIoCompletionPort")
+	procGetQueuedCompletionStatus                            = modkernel32.NewProc("GetQueuedCompletionStatus")
+	procSetFileCompletionNotificationModes                   = modkernel32.NewProc("SetFileCompletionNotificationModes")
+	procConnectNamedPipe                                     = modkernel32.NewProc("ConnectNamedPipe")
+	procCreateNamedPipeW                                     = modkernel32.NewProc("CreateNamedPipeW")
+	procCreateFileW                                          = modkernel32.NewProc("CreateFileW")
+	procWaitNamedPipeW                                       = modkernel32.NewProc("WaitNamedPipeW")
+	procGetNamedPipeInfo                                     = modkernel32.NewProc("GetNamedPipeInfo")
+	procGetNamedPipeHandleStateW                             = modkernel32.NewProc("GetNamedPipeHandleStateW")
+	procLocalAlloc                                           = modkernel32.NewProc("LocalAlloc")
+	procLookupAccountNameW                                   = modadvapi32.NewProc("LookupAccountNameW")
+	procConvertSidToStringSidW                               = modadvapi32.NewProc("ConvertSidToStringSidW")
+	procConvertStringSecurityDescriptorToSecurityDescriptorW = modadvapi32.NewProc("ConvertStringSecurityDescriptorToSecurityDescriptorW")
+	procConvertSecurityDescriptorToStringSecurityDescriptorW = modadvapi32.NewProc("ConvertSecurityDescriptorToStringSecurityDescriptorW")
+	procLocalFree                                            = modkernel32.NewProc("LocalFree")
+	procGetSecurityDescriptorLength                          = modadvapi32.NewProc("GetSecurityDescriptorLength")
+	procGetFileInformationByHandleEx                         = modkernel32.NewProc("GetFileInformationByHandleEx")
+	procSetFileInformationByHandle                           = modkernel32.NewProc("SetFileInformationByHandle")
+	procAdjustTokenPrivileges                                = modadvapi32.NewProc("AdjustTokenPrivileges")
+	procImpersonateSelf                                      = modadvapi32.NewProc("ImpersonateSelf")
+	procRevertToSelf                                         = modadvapi32.NewProc("RevertToSelf")
+	procOpenThreadToken                                      = modadvapi32.NewProc("OpenThreadToken")
+	procGetCurrentThread                                     = modkernel32.NewProc("GetCurrentThread")
+	procLookupPrivilegeValueW                                = modadvapi32.NewProc("LookupPrivilegeValueW")
+	procLookupPrivilegeNameW                                 = modadvapi32.NewProc("LookupPrivilegeNameW")
+	procLookupPrivilegeDisplayNameW                          = modadvapi32.NewProc("LookupPrivilegeDisplayNameW")
+	procBackupRead                                           = modkernel32.NewProc("BackupRead")
+	procBackupWrite                                          = modkernel32.NewProc("BackupWrite")
+)
+
+func cancelIoEx(file syscall.Handle, o *syscall.Overlapped) (err error) {
+	r1, _, e1 := syscall.Syscall(procCancelIoEx.Addr(), 2, uintptr(file), uintptr(unsafe.Pointer(o)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func createIoCompletionPort(file syscall.Handle, port syscall.Handle, key uintptr, threadCount uint32) (newport syscall.Handle, err error) {
+	r0, _, e1 := syscall.Syscall6(procCreateIoCompletionPort.Addr(), 4, uintptr(file), uintptr(port), uintptr(key), uintptr(threadCount), 0, 0)
+	newport = syscall.Handle(r0)
+	if newport == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func getQueuedCompletionStatus(port syscall.Handle, bytes *uint32, key *uintptr, o **ioOperation, timeout uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procGetQueuedCompletionStatus.Addr(), 5, uintptr(port), uintptr(unsafe.Pointer(bytes)), uintptr(unsafe.Pointer(key)), uintptr(unsafe.Pointer(o)), uintptr(timeout), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func setFileCompletionNotificationModes(h syscall.Handle, flags uint8) (err error) {
+	r1, _, e1 := syscall.Syscall(procSetFileCompletionNotificationModes.Addr(), 2, uintptr(h), uintptr(flags), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func connectNamedPipe(pipe syscall.Handle, o *syscall.Overlapped) (err error) {
+	r1, _, e1 := syscall.Syscall(procConnectNamedPipe.Addr(), 2, uintptr(pipe), uintptr(unsafe.Pointer(o)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func createNamedPipe(name string, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return
+	}
+	return _createNamedPipe(_p0, flags, pipeMode, maxInstances, outSize, inSize, defaultTimeout, sa)
+}
+
+func _createNamedPipe(name *uint16, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *syscall.SecurityAttributes) (handle syscall.Handle, err error) {
+	r0, _, e1 := syscall.Syscall9(procCreateNamedPipeW.Addr(), 8, uintptr(unsafe.Pointer(name)), uintptr(flags), uintptr(pipeMode), uintptr(maxInstances), uintptr(outSize), uintptr(inSize), uintptr(defaultTimeout), uintptr(unsafe.Pointer(sa)), 0)
+	handle = syscall.Handle(r0)
+	if handle == syscall.InvalidHandle {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func createFile(name string, access uint32, mode uint32, sa *syscall.SecurityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return
+	}
+	return _createFile(_p0, access, mode, sa, createmode, attrs, templatefile)
+}
+
+func _createFile(name *uint16, access uint32, mode uint32, sa *syscall.SecurityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) {
+	r0, _, e1 := syscall.Syscall9(procCreateFileW.Addr(), 7, uintptr(unsafe.Pointer(name)), uintptr(access), uintptr(mode), uintptr(unsafe.Pointer(sa)), uintptr(createmode), uintptr(attrs), uintptr(templatefile), 0, 0)
+	handle = syscall.Handle(r0)
+	if handle == syscall.InvalidHandle {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func waitNamedPipe(name string, timeout uint32) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return
+	}
+	return _waitNamedPipe(_p0, timeout)
+}
+
+func _waitNamedPipe(name *uint16, timeout uint32) (err error) {
+	r1, _, e1 := syscall.Syscall(procWaitNamedPipeW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(timeout), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func getNamedPipeInfo(pipe syscall.Handle, flags *uint32, outSize *uint32, inSize *uint32, maxInstances *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procGetNamedPipeInfo.Addr(), 5, uintptr(pipe), uintptr(unsafe.Pointer(flags)), uintptr(unsafe.Pointer(outSize)), uintptr(unsafe.Pointer(inSize)), uintptr(unsafe.Pointer(maxInstances)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func getNamedPipeHandleState(pipe syscall.Handle, state *uint32, curInstances *uint32, maxCollectionCount *uint32, collectDataTimeout *uint32, userName *uint16, maxUserNameSize uint32) (err error) {
+	r1, _, e1 := syscall.Syscall9(procGetNamedPipeHandleStateW.Addr(), 7, uintptr(pipe), uintptr(unsafe.Pointer(state)), uintptr(unsafe.Pointer(curInstances)), uintptr(unsafe.Pointer(maxCollectionCount)), uintptr(unsafe.Pointer(collectDataTimeout)), uintptr(unsafe.Pointer(userName)), uintptr(maxUserNameSize), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func localAlloc(uFlags uint32, length uint32) (ptr uintptr) {
+	r0, _, _ := syscall.Syscall(procLocalAlloc.Addr(), 2, uintptr(uFlags), uintptr(length), 0)
+	ptr = uintptr(r0)
+	return
+}
+
+func lookupAccountName(systemName *uint16, accountName string, sid *byte, sidSize *uint32, refDomain *uint16, refDomainSize *uint32, sidNameUse *uint32) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(accountName)
+	if err != nil {
+		return
+	}
+	return _lookupAccountName(systemName, _p0, sid, sidSize, refDomain, refDomainSize, sidNameUse)
+}
+
+func _lookupAccountName(systemName *uint16, accountName *uint16, sid *byte, sidSize *uint32, refDomain *uint16, refDomainSize *uint32, sidNameUse *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall9(procLookupAccountNameW.Addr(), 7, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(accountName)), uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(sidSize)), uintptr(unsafe.Pointer(refDomain)), uintptr(unsafe.Pointer(refDomainSize)), uintptr(unsafe.Pointer(sidNameUse)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func convertSidToStringSid(sid *byte, str **uint16) (err error) {
+	r1, _, e1 := syscall.Syscall(procConvertSidToStringSidW.Addr(), 2, uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(str)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func convertStringSecurityDescriptorToSecurityDescriptor(str string, revision uint32, sd *uintptr, size *uint32) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(str)
+	if err != nil {
+		return
+	}
+	return _convertStringSecurityDescriptorToSecurityDescriptor(_p0, revision, sd, size)
+}
+
+func _convertStringSecurityDescriptorToSecurityDescriptor(str *uint16, revision uint32, sd *uintptr, size *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procConvertStringSecurityDescriptorToSecurityDescriptorW.Addr(), 4, uintptr(unsafe.Pointer(str)), uintptr(revision), uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(size)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func convertSecurityDescriptorToStringSecurityDescriptor(sd *byte, revision uint32, secInfo uint32, sddl **uint16, sddlSize *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procConvertSecurityDescriptorToStringSecurityDescriptorW.Addr(), 5, uintptr(unsafe.Pointer(sd)), uintptr(revision), uintptr(secInfo), uintptr(unsafe.Pointer(sddl)), uintptr(unsafe.Pointer(sddlSize)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func localFree(mem uintptr) {
+	syscall.Syscall(procLocalFree.Addr(), 1, uintptr(mem), 0, 0)
+	return
+}
+
+func getSecurityDescriptorLength(sd uintptr) (len uint32) {
+	r0, _, _ := syscall.Syscall(procGetSecurityDescriptorLength.Addr(), 1, uintptr(sd), 0, 0)
+	len = uint32(r0)
+	return
+}
+
+func getFileInformationByHandleEx(h syscall.Handle, class uint32, buffer *byte, size uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procGetFileInformationByHandleEx.Addr(), 4, uintptr(h), uintptr(class), uintptr(unsafe.Pointer(buffer)), uintptr(size), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func setFileInformationByHandle(h syscall.Handle, class uint32, buffer *byte, size uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procSetFileInformationByHandle.Addr(), 4, uintptr(h), uintptr(class), uintptr(unsafe.Pointer(buffer)), uintptr(size), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func adjustTokenPrivileges(token windows.Token, releaseAll bool, input *byte, outputSize uint32, output *byte, requiredSize *uint32) (success bool, err error) {
+	var _p0 uint32
+	if releaseAll {
+		_p0 = 1
+	} else {
+		_p0 = 0
+	}
+	r0, _, e1 := syscall.Syscall6(procAdjustTokenPrivileges.Addr(), 6, uintptr(token), uintptr(_p0), uintptr(unsafe.Pointer(input)), uintptr(outputSize), uintptr(unsafe.Pointer(output)), uintptr(unsafe.Pointer(requiredSize)))
+	success = r0 != 0
+	if true {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func impersonateSelf(level uint32) (err error) {
+	r1, _, e1 := syscall.Syscall(procImpersonateSelf.Addr(), 1, uintptr(level), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func revertToSelf() (err error) {
+	r1, _, e1 := syscall.Syscall(procRevertToSelf.Addr(), 0, 0, 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func openThreadToken(thread syscall.Handle, accessMask uint32, openAsSelf bool, token *windows.Token) (err error) {
+	var _p0 uint32
+	if openAsSelf {
+		_p0 = 1
+	} else {
+		_p0 = 0
+	}
+	r1, _, e1 := syscall.Syscall6(procOpenThreadToken.Addr(), 4, uintptr(thread), uintptr(accessMask), uintptr(_p0), uintptr(unsafe.Pointer(token)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func getCurrentThread() (h syscall.Handle) {
+	r0, _, _ := syscall.Syscall(procGetCurrentThread.Addr(), 0, 0, 0, 0)
+	h = syscall.Handle(r0)
+	return
+}
+
+func lookupPrivilegeValue(systemName string, name string, luid *uint64) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(systemName)
+	if err != nil {
+		return
+	}
+	var _p1 *uint16
+	_p1, err = syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return
+	}
+	return _lookupPrivilegeValue(_p0, _p1, luid)
+}
+
+func _lookupPrivilegeValue(systemName *uint16, name *uint16, luid *uint64) (err error) {
+	r1, _, e1 := syscall.Syscall(procLookupPrivilegeValueW.Addr(), 3, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(luid)))
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func lookupPrivilegeName(systemName string, luid *uint64, buffer *uint16, size *uint32) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(systemName)
+	if err != nil {
+		return
+	}
+	return _lookupPrivilegeName(_p0, luid, buffer, size)
+}
+
+func _lookupPrivilegeName(systemName *uint16, luid *uint64, buffer *uint16, size *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procLookupPrivilegeNameW.Addr(), 4, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(luid)), uintptr(unsafe.Pointer(buffer)), uintptr(unsafe.Pointer(size)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func lookupPrivilegeDisplayName(systemName string, name *uint16, buffer *uint16, size *uint32, languageId *uint32) (err error) {
+	var _p0 *uint16
+	_p0, err = syscall.UTF16PtrFromString(systemName)
+	if err != nil {
+		return
+	}
+	return _lookupPrivilegeDisplayName(_p0, name, buffer, size, languageId)
+}
+
+func _lookupPrivilegeDisplayName(systemName *uint16, name *uint16, buffer *uint16, size *uint32, languageId *uint32) (err error) {
+	r1, _, e1 := syscall.Syscall6(procLookupPrivilegeDisplayNameW.Addr(), 5, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(buffer)), uintptr(unsafe.Pointer(size)), uintptr(unsafe.Pointer(languageId)), 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func backupRead(h syscall.Handle, b []byte, bytesRead *uint32, abort bool, processSecurity bool, context *uintptr) (err error) {
+	var _p0 *byte
+	if len(b) > 0 {
+		_p0 = &b[0]
+	}
+	var _p1 uint32
+	if abort {
+		_p1 = 1
+	} else {
+		_p1 = 0
+	}
+	var _p2 uint32
+	if processSecurity {
+		_p2 = 1
+	} else {
+		_p2 = 0
+	}
+	r1, _, e1 := syscall.Syscall9(procBackupRead.Addr(), 7, uintptr(h), uintptr(unsafe.Pointer(_p0)), uintptr(len(b)), uintptr(unsafe.Pointer(bytesRead)), uintptr(_p1), uintptr(_p2), uintptr(unsafe.Pointer(context)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
+
+func backupWrite(h syscall.Handle, b []byte, bytesWritten *uint32, abort bool, processSecurity bool, context *uintptr) (err error) {
+	var _p0 *byte
+	if len(b) > 0 {
+		_p0 = &b[0]
+	}
+	var _p1 uint32
+	if abort {
+		_p1 = 1
+	} else {
+		_p1 = 0
+	}
+	var _p2 uint32
+	if processSecurity {
+		_p2 = 1
+	} else {
+		_p2 = 0
+	}
+	r1, _, e1 := syscall.Syscall9(procBackupWrite.Addr(), 7, uintptr(h), uintptr(unsafe.Pointer(_p0)), uintptr(len(b)), uintptr(unsafe.Pointer(bytesWritten)), uintptr(_p1), uintptr(_p2), uintptr(unsafe.Pointer(context)), 0, 0)
+	if r1 == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}
@@ -0,0 +1,26 @@
+Copyright (c) 2012, Neal van Veen (nealvanveen@gmail.com)
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met: 
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer. 
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution. 
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+The views and conclusions contained in the software and documentation are those
+of the authors and should not be interpreted as representing official policies, 
+either expressed or implied, of the FreeBSD Project.
@@ -0,0 +1,5 @@
+Gotty is a library written in Go that determines and reads termcap database
+files to produce an interface for interacting with the capabilities of a
+terminal.
+See the godoc documentation or the source code for more information about
+function usage.
@@ -0,0 +1,3 @@
+gotty.go:// TODO add more concurrency to name lookup, look for more opportunities.
+all:// TODO add more documentation, with function usage in a doc.go file.
+all:// TODO add more testing/benchmarking with go test.
@@ -0,0 +1,514 @@
+// Copyright 2012 Neal van Veen. All rights reserved.
+// Usage of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package gotty
+
+// Boolean capabilities
+var BoolAttr = [...]string{
+	"auto_left_margin", "bw",
+	"auto_right_margin", "am",
+	"no_esc_ctlc", "xsb",
+	"ceol_standout_glitch", "xhp",
+	"eat_newline_glitch", "xenl",
+	"erase_overstrike", "eo",
+	"generic_type", "gn",
+	"hard_copy", "hc",
+	"has_meta_key", "km",
+	"has_status_line", "hs",
+	"insert_null_glitch", "in",
+	"memory_above", "da",
+	"memory_below", "db",
+	"move_insert_mode", "mir",
+	"move_standout_mode", "msgr",
+	"over_strike", "os",
+	"status_line_esc_ok", "eslok",
+	"dest_tabs_magic_smso", "xt",
+	"tilde_glitch", "hz",
+	"transparent_underline", "ul",
+	"xon_xoff", "nxon",
+	"needs_xon_xoff", "nxon",
+	"prtr_silent", "mc5i",
+	"hard_cursor", "chts",
+	"non_rev_rmcup", "nrrmc",
+	"no_pad_char", "npc",
+	"non_dest_scroll_region", "ndscr",
+	"can_change", "ccc",
+	"back_color_erase", "bce",
+	"hue_lightness_saturation", "hls",
+	"col_addr_glitch", "xhpa",
+	"cr_cancels_micro_mode", "crxm",
+	"has_print_wheel", "daisy",
+	"row_addr_glitch", "xvpa",
+	"semi_auto_right_margin", "sam",
+	"cpi_changes_res", "cpix",
+	"lpi_changes_res", "lpix",
+	"backspaces_with_bs", "",
+	"crt_no_scrolling", "",
+	"no_correctly_working_cr", "",
+	"gnu_has_meta_key", "",
+	"linefeed_is_newline", "",
+	"has_hardware_tabs", "",
+	"return_does_clr_eol", "",
+}
+
+// Numerical capabilities
+var NumAttr = [...]string{
+	"columns", "cols",
+	"init_tabs", "it",
+	"lines", "lines",
+	"lines_of_memory", "lm",
+	"magic_cookie_glitch", "xmc",
+	"padding_baud_rate", "pb",
+	"virtual_terminal", "vt",
+	"width_status_line", "wsl",
+	"num_labels", "nlab",
+	"label_height", "lh",
+	"label_width", "lw",
+	"max_attributes", "ma",
+	"maximum_windows", "wnum",
+	"max_colors", "colors",
+	"max_pairs", "pairs",
+	"no_color_video", "ncv",
+	"buffer_capacity", "bufsz",
+	"dot_vert_spacing", "spinv",
+	"dot_horz_spacing", "spinh",
+	"max_micro_address", "maddr",
+	"max_micro_jump", "mjump",
+	"micro_col_size", "mcs",
+	"micro_line_size", "mls",
+	"number_of_pins", "npins",
+	"output_res_char", "orc",
+	"output_res_line", "orl",
+	"output_res_horz_inch", "orhi",
+	"output_res_vert_inch", "orvi",
+	"print_rate", "cps",
+	"wide_char_size", "widcs",
+	"buttons", "btns",
+	"bit_image_entwining", "bitwin",
+	"bit_image_type", "bitype",
+	"magic_cookie_glitch_ul", "",
+	"carriage_return_delay", "",
+	"new_line_delay", "",
+	"backspace_delay", "",
+	"horizontal_tab_delay", "",
+	"number_of_function_keys", "",
+}
+
+// String capabilities
+var StrAttr = [...]string{
+	"back_tab", "cbt",
+	"bell", "bel",
+	"carriage_return", "cr",
+	"change_scroll_region", "csr",
+	"clear_all_tabs", "tbc",
+	"clear_screen", "clear",
+	"clr_eol", "el",
+	"clr_eos", "ed",
+	"column_address", "hpa",
+	"command_character", "cmdch",
+	"cursor_address", "cup",
+	"cursor_down", "cud1",
+	"cursor_home", "home",
+	"cursor_invisible", "civis",
+	"cursor_left", "cub1",
+	"cursor_mem_address", "mrcup",
+	"cursor_normal", "cnorm",
+	"cursor_right", "cuf1",
+	"cursor_to_ll", "ll",
+	"cursor_up", "cuu1",
+	"cursor_visible", "cvvis",
+	"delete_character", "dch1",
+	"delete_line", "dl1",
+	"dis_status_line", "dsl",
+	"down_half_line", "hd",
+	"enter_alt_charset_mode", "smacs",
+	"enter_blink_mode", "blink",
+	"enter_bold_mode", "bold",
+	"enter_ca_mode", "smcup",
+	"enter_delete_mode", "smdc",
+	"enter_dim_mode", "dim",
+	"enter_insert_mode", "smir",
+	"enter_secure_mode", "invis",
+	"enter_protected_mode", "prot",
+	"enter_reverse_mode", "rev",
+	"enter_standout_mode", "smso",
+	"enter_underline_mode", "smul",
+	"erase_chars", "ech",
+	"exit_alt_charset_mode", "rmacs",
+	"exit_attribute_mode", "sgr0",
+	"exit_ca_mode", "rmcup",
+	"exit_delete_mode", "rmdc",
+	"exit_insert_mode", "rmir",
+	"exit_standout_mode", "rmso",
+	"exit_underline_mode", "rmul",
+	"flash_screen", "flash",
+	"form_feed", "ff",
+	"from_status_line", "fsl",
+	"init_1string", "is1",
+	"init_2string", "is2",
+	"init_3string", "is3",
+	"init_file", "if",
+	"insert_character", "ich1",
+	"insert_line", "il1",
+	"insert_padding", "ip",
+	"key_backspace", "kbs",
+	"key_catab", "ktbc",
+	"key_clear", "kclr",
+	"key_ctab", "kctab",
+	"key_dc", "kdch1",
+	"key_dl", "kdl1",
+	"key_down", "kcud1",
+	"key_eic", "krmir",
+	"key_eol", "kel",
+	"key_eos", "ked",
+	"key_f0", "kf0",
+	"key_f1", "kf1",
+	"key_f10", "kf10",
+	"key_f2", "kf2",
+	"key_f3", "kf3",
+	"key_f4", "kf4",
+	"key_f5", "kf5",
+	"key_f6", "kf6",
+	"key_f7", "kf7",
+	"key_f8", "kf8",
+	"key_f9", "kf9",
+	"key_home", "khome",
+	"key_ic", "kich1",
+	"key_il", "kil1",
+	"key_left", "kcub1",
+	"key_ll", "kll",
+	"key_npage", "knp",
+	"key_ppage", "kpp",
+	"key_right", "kcuf1",
+	"key_sf", "kind",
+	"key_sr", "kri",
+	"key_stab", "khts",
+	"key_up", "kcuu1",
+	"keypad_local", "rmkx",
+	"keypad_xmit", "smkx",
+	"lab_f0", "lf0",
+	"lab_f1", "lf1",
+	"lab_f10", "lf10",
+	"lab_f2", "lf2",
+	"lab_f3", "lf3",
+	"lab_f4", "lf4",
+	"lab_f5", "lf5",
+	"lab_f6", "lf6",
+	"lab_f7", "lf7",
+	"lab_f8", "lf8",
+	"lab_f9", "lf9",
+	"meta_off", "rmm",
+	"meta_on", "smm",
+	"newline", "_glitch",
+	"pad_char", "npc",
+	"parm_dch", "dch",
+	"parm_delete_line", "dl",
+	"parm_down_cursor", "cud",
+	"parm_ich", "ich",
+	"parm_index", "indn",
+	"parm_insert_line", "il",
+	"parm_left_cursor", "cub",
+	"parm_right_cursor", "cuf",
+	"parm_rindex", "rin",
+	"parm_up_cursor", "cuu",
+	"pkey_key", "pfkey",
+	"pkey_local", "pfloc",
+	"pkey_xmit", "pfx",
+	"print_screen", "mc0",
+	"prtr_off", "mc4",
+	"prtr_on", "mc5",
+	"repeat_char", "rep",
+	"reset_1string", "rs1",
+	"reset_2string", "rs2",
+	"reset_3string", "rs3",
+	"reset_file", "rf",
+	"restore_cursor", "rc",
+	"row_address", "mvpa",
+	"save_cursor", "row_address",
+	"scroll_forward", "ind",
+	"scroll_reverse", "ri",
+	"set_attributes", "sgr",
+	"set_tab", "hts",
+	"set_window", "wind",
+	"tab", "s_magic_smso",
+	"to_status_line", "tsl",
+	"underline_char", "uc",
+	"up_half_line", "hu",
+	"init_prog", "iprog",
+	"key_a1", "ka1",
+	"key_a3", "ka3",
+	"key_b2", "kb2",
+	"key_c1", "kc1",
+	"key_c3", "kc3",
+	"prtr_non", "mc5p",
+	"char_padding", "rmp",
+	"acs_chars", "acsc",
+	"plab_norm", "pln",
+	"key_btab", "kcbt",
+	"enter_xon_mode", "smxon",
+	"exit_xon_mode", "rmxon",
+	"enter_am_mode", "smam",
+	"exit_am_mode", "rmam",
+	"xon_character", "xonc",
+	"xoff_character", "xoffc",
+	"ena_acs", "enacs",
+	"label_on", "smln",
+	"label_off", "rmln",
+	"key_beg", "kbeg",
+	"key_cancel", "kcan",
+	"key_close", "kclo",
+	"key_command", "kcmd",
+	"key_copy", "kcpy",
+	"key_create", "kcrt",
+	"key_end", "kend",
+	"key_enter", "kent",
+	"key_exit", "kext",
+	"key_find", "kfnd",
+	"key_help", "khlp",
+	"key_mark", "kmrk",
+	"key_message", "kmsg",
+	"key_move", "kmov",
+	"key_next", "knxt",
+	"key_open", "kopn",
+	"key_options", "kopt",
+	"key_previous", "kprv",
+	"key_print", "kprt",
+	"key_redo", "krdo",
+	"key_reference", "kref",
+	"key_refresh", "krfr",
+	"key_replace", "krpl",
+	"key_restart", "krst",
+	"key_resume", "kres",
+	"key_save", "ksav",
+	"key_suspend", "kspd",
+	"key_undo", "kund",
+	"key_sbeg", "kBEG",
+	"key_scancel", "kCAN",
+	"key_scommand", "kCMD",
+	"key_scopy", "kCPY",
+	"key_screate", "kCRT",
+	"key_sdc", "kDC",
+	"key_sdl", "kDL",
+	"key_select", "kslt",
+	"key_send", "kEND",
+	"key_seol", "kEOL",
+	"key_sexit", "kEXT",
+	"key_sfind", "kFND",
+	"key_shelp", "kHLP",
+	"key_shome", "kHOM",
+	"key_sic", "kIC",
+	"key_sleft", "kLFT",
+	"key_smessage", "kMSG",
+	"key_smove", "kMOV",
+	"key_snext", "kNXT",
+	"key_soptions", "kOPT",
+	"key_sprevious", "kPRV",
+	"key_sprint", "kPRT",
+	"key_sredo", "kRDO",
+	"key_sreplace", "kRPL",
+	"key_sright", "kRIT",
+	"key_srsume", "kRES",
+	"key_ssave", "kSAV",
+	"key_ssuspend", "kSPD",
+	"key_sundo", "kUND",
+	"req_for_input", "rfi",
+	"key_f11", "kf11",
+	"key_f12", "kf12",
+	"key_f13", "kf13",
+	"key_f14", "kf14",
+	"key_f15", "kf15",
+	"key_f16", "kf16",
+	"key_f17", "kf17",
+	"key_f18", "kf18",
+	"key_f19", "kf19",
+	"key_f20", "kf20",
+	"key_f21", "kf21",
+	"key_f22", "kf22",
+	"key_f23", "kf23",
+	"key_f24", "kf24",
+	"key_f25", "kf25",
+	"key_f26", "kf26",
+	"key_f27", "kf27",
+	"key_f28", "kf28",
+	"key_f29", "kf29",
+	"key_f30", "kf30",
+	"key_f31", "kf31",
+	"key_f32", "kf32",
+	"key_f33", "kf33",
+	"key_f34", "kf34",
+	"key_f35", "kf35",
+	"key_f36", "kf36",
+	"key_f37", "kf37",
+	"key_f38", "kf38",
+	"key_f39", "kf39",
+	"key_f40", "kf40",
+	"key_f41", "kf41",
+	"key_f42", "kf42",
+	"key_f43", "kf43",
+	"key_f44", "kf44",
+	"key_f45", "kf45",
+	"key_f46", "kf46",
+	"key_f47", "kf47",
+	"key_f48", "kf48",
+	"key_f49", "kf49",
+	"key_f50", "kf50",
+	"key_f51", "kf51",
+	"key_f52", "kf52",
+	"key_f53", "kf53",
+	"key_f54", "kf54",
+	"key_f55", "kf55",
+	"key_f56", "kf56",
+	"key_f57", "kf57",
+	"key_f58", "kf58",
+	"key_f59", "kf59",
+	"key_f60", "kf60",
+	"key_f61", "kf61",
+	"key_f62", "kf62",
+	"key_f63", "kf63",
+	"clr_bol", "el1",
+	"clear_margins", "mgc",
+	"set_left_margin", "smgl",
+	"set_right_margin", "smgr",
+	"label_format", "fln",
+	"set_clock", "sclk",
+	"display_clock", "dclk",
+	"remove_clock", "rmclk",
+	"create_window", "cwin",
+	"goto_window", "wingo",
+	"hangup", "hup",
+	"dial_phone", "dial",
+	"quick_dial", "qdial",
+	"tone", "tone",
+	"pulse", "pulse",
+	"flash_hook", "hook",
+	"fixed_pause", "pause",
+	"wait_tone", "wait",
+	"user0", "u0",
+	"user1", "u1",
+	"user2", "u2",
+	"user3", "u3",
+	"user4", "u4",
+	"user5", "u5",
+	"user6", "u6",
+	"user7", "u7",
+	"user8", "u8",
+	"user9", "u9",
+	"orig_pair", "op",
+	"orig_colors", "oc",
+	"initialize_color", "initc",
+	"initialize_pair", "initp",
+	"set_color_pair", "scp",
+	"set_foreground", "setf",
+	"set_background", "setb",
+	"change_char_pitch", "cpi",
+	"change_line_pitch", "lpi",
+	"change_res_horz", "chr",
+	"change_res_vert", "cvr",
+	"define_char", "defc",
+	"enter_doublewide_mode", "swidm",
+	"enter_draft_quality", "sdrfq",
+	"enter_italics_mode", "sitm",
+	"enter_leftward_mode", "slm",
+	"enter_micro_mode", "smicm",
+	"enter_near_letter_quality", "snlq",
+	"enter_normal_quality", "snrmq",
+	"enter_shadow_mode", "sshm",
+	"enter_subscript_mode", "ssubm",
+	"enter_superscript_mode", "ssupm",
+	"enter_upward_mode", "sum",
+	"exit_doublewide_mode", "rwidm",
+	"exit_italics_mode", "ritm",
+	"exit_leftward_mode", "rlm",
+	"exit_micro_mode", "rmicm",
+	"exit_shadow_mode", "rshm",
+	"exit_subscript_mode", "rsubm",
+	"exit_superscript_mode", "rsupm",
+	"exit_upward_mode", "rum",
+	"micro_column_address", "mhpa",
+	"micro_down", "mcud1",
+	"micro_left", "mcub1",
+	"micro_right", "mcuf1",
+	"micro_row_address", "mvpa",
+	"micro_up", "mcuu1",
+	"order_of_pins", "porder",
+	"parm_down_micro", "mcud",
+	"parm_left_micro", "mcub",
+	"parm_right_micro", "mcuf",
+	"parm_up_micro", "mcuu",
+	"select_char_set", "scs",
+	"set_bottom_margin", "smgb",
+	"set_bottom_margin_parm", "smgbp",
+	"set_left_margin_parm", "smglp",
+	"set_right_margin_parm", "smgrp",
+	"set_top_margin", "smgt",
+	"set_top_margin_parm", "smgtp",
+	"start_bit_image", "sbim",
+	"start_char_set_def", "scsd",
+	"stop_bit_image", "rbim",
+	"stop_char_set_def", "rcsd",
+	"subscript_characters", "subcs",
+	"superscript_characters", "supcs",
+	"these_cause_cr", "docr",
+	"zero_motion", "zerom",
+	"char_set_names", "csnm",
+	"key_mouse", "kmous",
+	"mouse_info", "minfo",
+	"req_mouse_pos", "reqmp",
+	"get_mouse", "getm",
+	"set_a_foreground", "setaf",
+	"set_a_background", "setab",
+	"pkey_plab", "pfxl",
+	"device_type", "devt",
+	"code_set_init", "csin",
+	"set0_des_seq", "s0ds",
+	"set1_des_seq", "s1ds",
+	"set2_des_seq", "s2ds",
+	"set3_des_seq", "s3ds",
+	"set_lr_margin", "smglr",
+	"set_tb_margin", "smgtb",
+	"bit_image_repeat", "birep",
+	"bit_image_newline", "binel",
+	"bit_image_carriage_return", "bicr",
+	"color_names", "colornm",
+	"define_bit_image_region", "defbi",
+	"end_bit_image_region", "endbi",
+	"set_color_band", "setcolor",
+	"set_page_length", "slines",
+	"display_pc_char", "dispc",
+	"enter_pc_charset_mode", "smpch",
+	"exit_pc_charset_mode", "rmpch",
+	"enter_scancode_mode", "smsc",
+	"exit_scancode_mode", "rmsc",
+	"pc_term_options", "pctrm",
+	"scancode_escape", "scesc",
+	"alt_scancode_esc", "scesa",
+	"enter_horizontal_hl_mode", "ehhlm",
+	"enter_left_hl_mode", "elhlm",
+	"enter_low_hl_mode", "elohlm",
+	"enter_right_hl_mode", "erhlm",
+	"enter_top_hl_mode", "ethlm",
+	"enter_vertical_hl_mode", "evhlm",
+	"set_a_attributes", "sgr1",
+	"set_pglen_inch", "slength",
+	"termcap_init2", "",
+	"termcap_reset", "",
+	"linefeed_if_not_lf", "",
+	"backspace_if_not_bs", "",
+	"other_non_function_keys", "",
+	"arrow_key_map", "",
+	"acs_ulcorner", "",
+	"acs_llcorner", "",
+	"acs_urcorner", "",
+	"acs_lrcorner", "",
+	"acs_ltee", "",
+	"acs_rtee", "",
+	"acs_btee", "",
+	"acs_ttee", "",
+	"acs_hline", "",
+	"acs_vline", "",
+	"acs_plus", "",
+	"memory_lock", "",
+	"memory_unlock", "",
+	"box_chars_1", "",
+}
@@ -0,0 +1,238 @@
+// Copyright 2012 Neal van Veen. All rights reserved.
+// Usage of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Gotty is a Go-package for reading and parsing the terminfo database
+package gotty
+
+// TODO add more concurrency to name lookup, look for more opportunities.
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"os"
+	"reflect"
+	"strings"
+	"sync"
+)
+
+// Open a terminfo file by the name given and construct a TermInfo object.
+// If something went wrong reading the terminfo database file, an error is
+// returned.
+func OpenTermInfo(termName string) (*TermInfo, error) {
+	var term *TermInfo
+	var err error
+	// Find the environment variables
+	termloc := os.Getenv("TERMINFO")
+	if len(termloc) == 0 {
+		// Search like ncurses
+		locations := []string{os.Getenv("HOME") + "/.terminfo/", "/etc/terminfo/",
+			"/lib/terminfo/", "/usr/share/terminfo/"}
+		var path string
+		for _, str := range locations {
+			// Construct path
+			path = str + string(termName[0]) + "/" + termName
+			// Check if path can be opened
+			file, _ := os.Open(path)
+			if file != nil {
+				// Path can open, fall out and use current path
+				file.Close()
+				break
+			}
+		}
+		if len(path) > 0 {
+			term, err = readTermInfo(path)
+		} else {
+			err = errors.New(fmt.Sprintf("No terminfo file(-location) found"))
+		}
+	}
+	return term, err
+}
+
+// Open a terminfo file from the environment variable containing the current
+// terminal name and construct a TermInfo object. If something went wrong
+// reading the terminfo database file, an error is returned.
+func OpenTermInfoEnv() (*TermInfo, error) {
+	termenv := os.Getenv("TERM")
+	return OpenTermInfo(termenv)
+}
+
+// Return an attribute by the name attr provided. If none can be found,
+// an error is returned.
+func (term *TermInfo) GetAttribute(attr string) (stacker, error) {
+	// Channel to store the main value in.
+	var value stacker
+	// Add a blocking WaitGroup
+	var block sync.WaitGroup
+	// Keep track of variable being written.
+	written := false
+	// Function to put into goroutine.
+	f := func(ats interface{}) {
+		var ok bool
+		var v stacker
+		// Switch on type of map to use and assign value to it.
+		switch reflect.TypeOf(ats).Elem().Kind() {
+		case reflect.Bool:
+			v, ok = ats.(map[string]bool)[attr]
+		case reflect.Int16:
+			v, ok = ats.(map[string]int16)[attr]
+		case reflect.String:
+			v, ok = ats.(map[string]string)[attr]
+		}
+		// If ok, a value is found, so we can write.
+		if ok {
+			value = v
+			written = true
+		}
+		// Goroutine is done
+		block.Done()
+	}
+	block.Add(3)
+	// Go for all 3 attribute lists.
+	go f(term.boolAttributes)
+	go f(term.numAttributes)
+	go f(term.strAttributes)
+	// Wait until every goroutine is done.
+	block.Wait()
+	// If a value has been written, return it.
+	if written {
+		return value, nil
+	}
+	// Otherwise, error.
+	return nil, fmt.Errorf("Erorr finding attribute")
+}
+
+// Return an attribute by the name attr provided. If none can be found,
+// an error is returned. A name is first converted to its termcap value.
+func (term *TermInfo) GetAttributeName(name string) (stacker, error) {
+	tc := GetTermcapName(name)
+	return term.GetAttribute(tc)
+}
+
+// A utility function that finds and returns the termcap equivalent of a 
+// variable name.
+func GetTermcapName(name string) string {
+	// Termcap name
+	var tc string
+	// Blocking group
+	var wait sync.WaitGroup
+	// Function to put into a goroutine
+	f := func(attrs []string) {
+		// Find the string corresponding to the name
+		for i, s := range attrs {
+			if s == name {
+				tc = attrs[i+1]
+			}
+		}
+		// Goroutine is finished
+		wait.Done()
+	}
+	wait.Add(3)
+	// Go for all 3 attribute lists
+	go f(BoolAttr[:])
+	go f(NumAttr[:])
+	go f(StrAttr[:])
+	// Wait until every goroutine is done
+	wait.Wait()
+	// Return the termcap name
+	return tc
+}
+
+// This function takes a path to a terminfo file and reads it in binary
+// form to construct the actual TermInfo file.
+func readTermInfo(path string) (*TermInfo, error) {
+	// Open the terminfo file
+	file, err := os.Open(path)
+	defer file.Close()
+	if err != nil {
+		return nil, err
+	}
+
+	// magic, nameSize, boolSize, nrSNum, nrOffsetsStr, strSize
+	// Header is composed of the magic 0432 octal number, size of the name
+	// section, size of the boolean section, the amount of number values,
+	// the number of offsets of strings, and the size of the string section.
+	var header [6]int16
+	// Byte array is used to read in byte values
+	var byteArray []byte
+	// Short array is used to read in short values
+	var shArray []int16
+	// TermInfo object to store values
+	var term TermInfo
+
+	// Read in the header
+	err = binary.Read(file, binary.LittleEndian, &header)
+	if err != nil {
+		return nil, err
+	}
+	// If magic number isn't there or isn't correct, we have the wrong filetype
+	if header[0] != 0432 {
+		return nil, errors.New(fmt.Sprintf("Wrong filetype"))
+	}
+
+	// Read in the names
+	byteArray = make([]byte, header[1])
+	err = binary.Read(file, binary.LittleEndian, &byteArray)
+	if err != nil {
+		return nil, err
+	}
+	term.Names = strings.Split(string(byteArray), "|")
+
+	// Read in the booleans
+	byteArray = make([]byte, header[2])
+	err = binary.Read(file, binary.LittleEndian, &byteArray)
+	if err != nil {
+		return nil, err
+	}
+	term.boolAttributes = make(map[string]bool)
+	for i, b := range byteArray {
+		if b == 1 {
+			term.boolAttributes[BoolAttr[i*2+1]] = true
+		}
+	}
+	// If the number of bytes read is not even, a byte for alignment is added
+	if len(byteArray)%2 != 0 {
+		err = binary.Read(file, binary.LittleEndian, make([]byte, 1))
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// Read in shorts
+	shArray = make([]int16, header[3])
+	err = binary.Read(file, binary.LittleEndian, &shArray)
+	if err != nil {
+		return nil, err
+	}
+	term.numAttributes = make(map[string]int16)
+	for i, n := range shArray {
+		if n != 0377 && n > -1 {
+			term.numAttributes[NumAttr[i*2+1]] = n
+		}
+	}
+
+	// Read the offsets into the short array
+	shArray = make([]int16, header[4])
+	err = binary.Read(file, binary.LittleEndian, &shArray)
+	if err != nil {
+		return nil, err
+	}
+	// Read the actual strings in the byte array
+	byteArray = make([]byte, header[5])
+	err = binary.Read(file, binary.LittleEndian, &byteArray)
+	if err != nil {
+		return nil, err
+	}
+	term.strAttributes = make(map[string]string)
+	// We get an offset, and then iterate until the string is null-terminated
+	for i, offset := range shArray {
+		if offset > -1 {
+			r := offset
+			for ; byteArray[r] != 0; r++ {
+			}
+			term.strAttributes[StrAttr[i*2+1]] = string(byteArray[offset:r])
+		}
+	}
+	return &term, nil
+}
@@ -0,0 +1,362 @@
+// Copyright 2012 Neal van Veen. All rights reserved.
+// Usage of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package gotty
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var exp = [...]string{
+	"%%",
+	"%c",
+	"%s",
+	"%p(\\d)",
+	"%P([A-z])",
+	"%g([A-z])",
+	"%'(.)'",
+	"%{([0-9]+)}",
+	"%l",
+	"%\\+|%-|%\\*|%/|%m",
+	"%&|%\\||%\\^",
+	"%=|%>|%<",
+	"%A|%O",
+	"%!|%~",
+	"%i",
+	"%(:[\\ #\\-\\+]{0,4})?(\\d+\\.\\d+|\\d+)?[doxXs]",
+	"%\\?(.*?);",
+}
+
+var regex *regexp.Regexp
+var staticVar map[byte]stacker
+
+// Parses the attribute that is received with name attr and parameters params.
+func (term *TermInfo) Parse(attr string, params ...interface{}) (string, error) {
+	// Get the attribute name first.
+	iface, err := term.GetAttribute(attr)
+	str, ok := iface.(string)
+	if err != nil {
+		return "", err
+	}
+	if !ok {
+		return str, errors.New("Only string capabilities can be parsed.")
+	}
+	// Construct the hidden parser struct so we can use a recursive stack based
+	// parser.
+	ps := &parser{}
+	// Dynamic variables only exist in this context.
+	ps.dynamicVar = make(map[byte]stacker, 26)
+	ps.parameters = make([]stacker, len(params))
+	// Convert the parameters to insert them into the parser struct.
+	for i, x := range params {
+		ps.parameters[i] = x
+	}
+	// Recursively walk and return.
+	result, err := ps.walk(str)
+	return result, err
+}
+
+// Parses the attribute that is received with name attr and parameters params.
+// Only works on full name of a capability that is given, which it uses to
+// search for the termcap name.
+func (term *TermInfo) ParseName(attr string, params ...interface{}) (string, error) {
+	tc := GetTermcapName(attr)
+	return term.Parse(tc, params)
+}
+
+// Identify each token in a stack based manner and do the actual parsing.
+func (ps *parser) walk(attr string) (string, error) {
+	// We use a buffer to get the modified string.
+	var buf bytes.Buffer
+	// Next, find and identify all tokens by their indices and strings.
+	tokens := regex.FindAllStringSubmatch(attr, -1)
+	if len(tokens) == 0 {
+		return attr, nil
+	}
+	indices := regex.FindAllStringIndex(attr, -1)
+	q := 0 // q counts the matches of one token
+	// Iterate through the string per character.
+	for i := 0; i < len(attr); i++ {
+		// If the current position is an identified token, execute the following
+		// steps.
+		if q < len(indices) && i >= indices[q][0] && i < indices[q][1] {
+			// Switch on token.
+			switch {
+			case tokens[q][0][:2] == "%%":
+				// Literal percentage character.
+				buf.WriteByte('%')
+			case tokens[q][0][:2] == "%c":
+				// Pop a character.
+				c, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				buf.WriteByte(c.(byte))
+			case tokens[q][0][:2] == "%s":
+				// Pop a string.
+				str, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				if _, ok := str.(string); !ok {
+					return buf.String(), errors.New("Stack head is not a string")
+				}
+				buf.WriteString(str.(string))
+			case tokens[q][0][:2] == "%p":
+				// Push a parameter on the stack.
+				index, err := strconv.ParseInt(tokens[q][1], 10, 8)
+				index--
+				if err != nil {
+					return buf.String(), err
+				}
+				if int(index) >= len(ps.parameters) {
+					return buf.String(), errors.New("Parameters index out of bound")
+				}
+				ps.st.push(ps.parameters[index])
+			case tokens[q][0][:2] == "%P":
+				// Pop a variable from the stack as a dynamic or static variable.
+				val, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				index := tokens[q][2]
+				if len(index) > 1 {
+					errorStr := fmt.Sprintf("%s is not a valid dynamic variables index",
+						index)
+					return buf.String(), errors.New(errorStr)
+				}
+				// Specify either dynamic or static.
+				if index[0] >= 'a' && index[0] <= 'z' {
+					ps.dynamicVar[index[0]] = val
+				} else if index[0] >= 'A' && index[0] <= 'Z' {
+					staticVar[index[0]] = val
+				}
+			case tokens[q][0][:2] == "%g":
+				// Push a variable from the stack as a dynamic or static variable.
+				index := tokens[q][3]
+				if len(index) > 1 {
+					errorStr := fmt.Sprintf("%s is not a valid static variables index",
+						index)
+					return buf.String(), errors.New(errorStr)
+				}
+				var val stacker
+				if index[0] >= 'a' && index[0] <= 'z' {
+					val = ps.dynamicVar[index[0]]
+				} else if index[0] >= 'A' && index[0] <= 'Z' {
+					val = staticVar[index[0]]
+				}
+				ps.st.push(val)
+			case tokens[q][0][:2] == "%'":
+				// Push a character constant.
+				con := tokens[q][4]
+				if len(con) > 1 {
+					errorStr := fmt.Sprintf("%s is not a valid character constant", con)
+					return buf.String(), errors.New(errorStr)
+				}
+				ps.st.push(con[0])
+			case tokens[q][0][:2] == "%{":
+				// Push an integer constant.
+				con, err := strconv.ParseInt(tokens[q][5], 10, 32)
+				if err != nil {
+					return buf.String(), err
+				}
+				ps.st.push(con)
+			case tokens[q][0][:2] == "%l":
+				// Push the length of the string that is popped from the stack.
+				popStr, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				if _, ok := popStr.(string); !ok {
+					errStr := fmt.Sprintf("Stack head is not a string")
+					return buf.String(), errors.New(errStr)
+				}
+				ps.st.push(len(popStr.(string)))
+			case tokens[q][0][:2] == "%?":
+				// If-then-else construct. First, the whole string is identified and
+				// then inside this substring, we can specify which parts to switch on.
+				ifReg, _ := regexp.Compile("%\\?(.*)%t(.*)%e(.*);|%\\?(.*)%t(.*);")
+				ifTokens := ifReg.FindStringSubmatch(tokens[q][0])
+				var (
+					ifStr string
+					err   error
+				)
+				// Parse the if-part to determine if-else.
+				if len(ifTokens[1]) > 0 {
+					ifStr, err = ps.walk(ifTokens[1])
+				} else { // else
+					ifStr, err = ps.walk(ifTokens[4])
+				}
+				// Return any errors
+				if err != nil {
+					return buf.String(), err
+				} else if len(ifStr) > 0 {
+					// Self-defined limitation, not sure if this is correct, but didn't
+					// seem like it.
+					return buf.String(), errors.New("If-clause cannot print statements")
+				}
+				var thenStr string
+				// Pop the first value that is set by parsing the if-clause.
+				choose, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				// Switch to if or else.
+				if choose.(int) == 0 && len(ifTokens[1]) > 0 {
+					thenStr, err = ps.walk(ifTokens[3])
+				} else if choose.(int) != 0 {
+					if len(ifTokens[1]) > 0 {
+						thenStr, err = ps.walk(ifTokens[2])
+					} else {
+						thenStr, err = ps.walk(ifTokens[5])
+					}
+				}
+				if err != nil {
+					return buf.String(), err
+				}
+				buf.WriteString(thenStr)
+			case tokens[q][0][len(tokens[q][0])-1] == 'd': // Fallthrough for printing
+				fallthrough
+			case tokens[q][0][len(tokens[q][0])-1] == 'o': // digits.
+				fallthrough
+			case tokens[q][0][len(tokens[q][0])-1] == 'x':
+				fallthrough
+			case tokens[q][0][len(tokens[q][0])-1] == 'X':
+				fallthrough
+			case tokens[q][0][len(tokens[q][0])-1] == 's':
+				token := tokens[q][0]
+				// Remove the : that comes before a flag.
+				if token[1] == ':' {
+					token = token[:1] + token[2:]
+				}
+				digit, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				// The rest is determined like the normal formatted prints.
+				digitStr := fmt.Sprintf(token, digit.(int))
+				buf.WriteString(digitStr)
+			case tokens[q][0][:2] == "%i":
+				// Increment the parameters by one.
+				if len(ps.parameters) < 2 {
+					return buf.String(), errors.New("Not enough parameters to increment.")
+				}
+				val1, val2 := ps.parameters[0].(int), ps.parameters[1].(int)
+				val1++
+				val2++
+				ps.parameters[0], ps.parameters[1] = val1, val2
+			default:
+				// The rest of the tokens is a special case, where two values are
+				// popped and then operated on by the token that comes after them.
+				op1, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				op2, err := ps.st.pop()
+				if err != nil {
+					return buf.String(), err
+				}
+				var result stacker
+				switch tokens[q][0][:2] {
+				case "%+":
+					// Addition
+					result = op2.(int) + op1.(int)
+				case "%-":
+					// Subtraction
+					result = op2.(int) - op1.(int)
+				case "%*":
+					// Multiplication
+					result = op2.(int) * op1.(int)
+				case "%/":
+					// Division
+					result = op2.(int) / op1.(int)
+				case "%m":
+					// Modulo
+					result = op2.(int) % op1.(int)
+				case "%&":
+					// Bitwise AND
+					result = op2.(int) & op1.(int)
+				case "%|":
+					// Bitwise OR
+					result = op2.(int) | op1.(int)
+				case "%^":
+					// Bitwise XOR
+					result = op2.(int) ^ op1.(int)
+				case "%=":
+					// Equals
+					result = op2 == op1
+				case "%>":
+					// Greater-than
+					result = op2.(int) > op1.(int)
+				case "%<":
+					// Lesser-than
+					result = op2.(int) < op1.(int)
+				case "%A":
+					// Logical AND
+					result = op2.(bool) && op1.(bool)
+				case "%O":
+					// Logical OR
+					result = op2.(bool) || op1.(bool)
+				case "%!":
+					// Logical complement
+					result = !op1.(bool)
+				case "%~":
+					// Bitwise complement
+					result = ^(op1.(int))
+				}
+				ps.st.push(result)
+			}
+
+			i = indices[q][1] - 1
+			q++
+		} else {
+			// We are not "inside" a token, so just skip until the end or the next
+			// token, and add all characters to the buffer.
+			j := i
+			if q != len(indices) {
+				for !(j >= indices[q][0] && j < indices[q][1]) {
+					j++
+				}
+			} else {
+				j = len(attr)
+			}
+			buf.WriteString(string(attr[i:j]))
+			i = j
+		}
+	}
+	// Return the buffer as a string.
+	return buf.String(), nil
+}
+
+// Push a stacker-value onto the stack.
+func (st *stack) push(s stacker) {
+	*st = append(*st, s)
+}
+
+// Pop a stacker-value from the stack.
+func (st *stack) pop() (stacker, error) {
+	if len(*st) == 0 {
+		return nil, errors.New("Stack is empty.")
+	}
+	newStack := make(stack, len(*st)-1)
+	val := (*st)[len(*st)-1]
+	copy(newStack, (*st)[:len(*st)-1])
+	*st = newStack
+	return val, nil
+}
+
+// Initialize regexes and the static vars (that don't get changed between
+// calls.
+func init() {
+	// Initialize the main regex.
+	expStr := strings.Join(exp[:], "|")
+	regex, _ = regexp.Compile(expStr)
+	// Initialize the static variables.
+	staticVar = make(map[byte]stacker, 26)
+}
@@ -0,0 +1,23 @@
+// Copyright 2012 Neal van Veen. All rights reserved.
+// Usage of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package gotty
+
+type TermInfo struct {
+	boolAttributes map[string]bool
+	numAttributes  map[string]int16
+	strAttributes  map[string]string
+	// The various names of the TermInfo file.
+	Names []string
+}
+
+type stacker interface {
+}
+type stack []stacker
+
+type parser struct {
+	st         stack
+	parameters []stacker
+	dynamicVar map[byte]stacker
+}
@@ -0,0 +1,309 @@
+# bit
+--
+    import "github.com/andybalholm/go-bit"
+
+Package bit provides a bitset implementation and utility bit functions for
+uint64 words.
+
+## Usage
+
+```go
+const (
+	MaxInt  = 1<<(BitsPerWord-1) - 1 // either 1<<31 - 1 or 1<<63 - 1
+	MinInt  = -MaxInt - 1            // either -1 << 31 or -1 << 63
+	MaxUint = 1<<BitsPerWord - 1     // either 1<<32 - 1 or 1<<64 - 1
+)
+```
+Implementation-specific integer limit values.
+
+```go
+const BitsPerWord = bitsPerWord // either 32 or 64
+
+```
+Implementation-specific size of int and uint in bits.
+
+#### func  Count
+
+```go
+func Count(w uint64) int
+```
+Count returns the number of nonzero bits in w.
+
+#### func  MaxPos
+
+```go
+func MaxPos(w uint64) int
+```
+MaxPos returns the position of the maximum nonzero bit in w, w ≠ 0. It panics
+for w = 0.
+
+#### func  MinPos
+
+```go
+func MinPos(w uint64) int
+```
+MinPos returns the position of the minimum nonzero bit in w, w ≠ 0. It panics
+for w = 0.
+
+#### type Set
+
+```go
+type Set struct {
+}
+```
+
+Set represents a mutable set of non-negative integers. The zero value of Set is
+an empty set ready to use. A set occupies approximately n bits, where n is the
+maximum value that has been stored in the set.
+
+#### func  New
+
+```go
+func New(n ...int) (S *Set)
+```
+New creates a new set S with the given elements.
+
+#### func (*Set) Add
+
+```go
+func (S *Set) Add(n int) *Set
+```
+Add adds n to S, setting S to S ∪ {n}, and returns the updated set.
+
+#### func (*Set) AddRange
+
+```go
+func (S *Set) AddRange(m, n int) *Set
+```
+AddRange adds all integers between m and n-1, m ≤ n, setting S to S ∪ {m..n-1},
+and returns the updated set.
+
+#### func (*Set) And
+
+```go
+func (A *Set) And(B *Set) (S *Set)
+```
+And creates a new intersection S = A ∩ B that consists of all elements that
+belong to both A and B.
+
+#### func (*Set) AndNot
+
+```go
+func (A *Set) AndNot(B *Set) (S *Set)
+```
+AndNot creates a new set difference S = A ∖ B that consists of all elements that
+belong to A, but not to B.
+
+#### func (*Set) Clear
+
+```go
+func (S *Set) Clear() *Set
+```
+Clear removes all elements and returns the updated empty set.
+
+#### func (*Set) Contains
+
+```go
+func (S *Set) Contains(n int) bool
+```
+Contains returns true if n, n ≥ 0, is an element of S.
+
+#### func (*Set) Do
+
+```go
+func (S *Set) Do(f func(n int))
+```
+Do calls function f for each element n ∊ S in numerical order. It is safe for f
+to add or remove elements e, e ≤ n, from S. The behavior of Do is undefined if f
+changes the set in any other way.
+
+#### func (*Set) Equals
+
+```go
+func (A *Set) Equals(B *Set) bool
+```
+Equals returns true if A and B contain the same elements.
+
+#### func (*Set) Flip
+
+```go
+func (S *Set) Flip(n int) *Set
+```
+Flip removes n from S if it is present, otherwise it adds n, setting S to S ∆
+{n}, and returns the updated set.
+
+#### func (*Set) FlipRange
+
+```go
+func (S *Set) FlipRange(m, n int) *Set
+```
+FlipRange flips all elements in the range m..n-1, m ≤ n, setting S to S ∆
+{m..n-1}, and returns the updated set.
+
+#### func (*Set) Intersects
+
+```go
+func (A *Set) Intersects(B *Set) bool
+```
+Intersects returns true if A and B overlap, i.e. A ∩ B ≠ ∅.
+
+#### func (*Set) IsEmpty
+
+```go
+func (S *Set) IsEmpty() bool
+```
+IsEmpty returns true if S = ∅.
+
+#### func (*Set) Max
+
+```go
+func (S *Set) Max() int
+```
+Max returns the maximum element of the set. It panics if S is empty.
+
+#### func (*Set) Min
+
+```go
+func (S *Set) Min() int
+```
+Min returns the minimum element of the set. It panics if S is empty.
+
+#### func (*Set) Next
+
+```go
+func (S *Set) Next(m int) (n int, found bool)
+```
+Next returns (n, true), where n is the smallest element of S such that m < n, or
+(0, false) if no such element exists.
+
+#### func (*Set) Or
+
+```go
+func (A *Set) Or(B *Set) (S *Set)
+```
+Or creates a new union S = A ∪ B that contains all elements that belong to
+either A or B.
+
+#### func (*Set) Previous
+
+```go
+func (S *Set) Previous(m int) (n int, found bool)
+```
+Previous returns (n, true), where n is the largest element of S such that n < m,
+or (0, false) if no such element exists.
+
+#### func (*Set) Remove
+
+```go
+func (S *Set) Remove(n int) *Set
+```
+Remove removes n from S, setting S to S ∖ {n}, and returns the updated set.
+
+#### func (*Set) RemoveMax
+
+```go
+func (S *Set) RemoveMax() (max int)
+```
+RemoveMax removes the maximum element from S, setting S to S ∖ {max}, and
+returns max. It panics if S is empty.
+
+#### func (*Set) RemoveMin
+
+```go
+func (S *Set) RemoveMin() (min int)
+```
+RemoveMin removes the minimum element from S, setting S to S ∖ {min}, and
+returns min. It panics if S is empty.
+
+#### func (*Set) RemoveRange
+
+```go
+func (S *Set) RemoveRange(m, n int) *Set
+```
+RemoveRange removes all integers between m and n-1, m ≤ n, setting S to S ∖
+{m..n-1}, and returns the updated set.
+
+#### func (*Set) Set
+
+```go
+func (S *Set) Set(A *Set) *Set
+```
+Set sets S to A and returns S.
+
+#### func (*Set) SetAnd
+
+```go
+func (S *Set) SetAnd(A, B *Set) *Set
+```
+SetAnd sets S to the intersection A ∩ B and returns S.
+
+#### func (*Set) SetAndNot
+
+```go
+func (S *Set) SetAndNot(A, B *Set) *Set
+```
+SetAndNot sets S to the set difference A ∖ B and returns S.
+
+#### func (*Set) SetOr
+
+```go
+func (S *Set) SetOr(A, B *Set) *Set
+```
+SetOr sets S to the union A ∪ B and returns S.
+
+#### func (*Set) SetWord
+
+```go
+func (S *Set) SetWord(i int, w uint64) *Set
+```
+SetWord interprets w as a bitset with numbers in the range 64i to 64i + 63,
+where 0 ≤ i ≤ ⌊MaxInt/64⌋, overwrites this range in S with w, and returns S.
+
+#### func (*Set) SetXor
+
+```go
+func (S *Set) SetXor(A, B *Set) *Set
+```
+SetXor sets S to the symmetric difference A ∆ B = (A ∪ B) ∖ (A ∩ B) and returns
+S.
+
+#### func (*Set) Size
+
+```go
+func (S *Set) Size() int
+```
+Size returns |S|, the number of elements in S. This method scans the set. To
+check if a set is empty, consider using the more efficient IsEmpty.
+
+#### func (*Set) String
+
+```go
+func (S *Set) String() string
+```
+String returns a string representation of S. The elements are listed in
+ascending order, enclosed by braces, and separated by ", ". Runs of at least
+three elements a, a+1, ..., b are given as "a..b".
+
+For example, the set {1, 2, 6, 5, 3} is represented as "{1..3, 5, 6}".
+
+#### func (*Set) SubsetOf
+
+```go
+func (A *Set) SubsetOf(B *Set) bool
+```
+SubsetOf returns true if A ⊆ B.
+
+#### func (*Set) Word
+
+```go
+func (S *Set) Word(i int) (w uint64)
+```
+Word returns the range 64i to 64i + 63 of S as a bitset represented by w.
+
+#### func (*Set) Xor
+
+```go
+func (A *Set) Xor(B *Set) (S *Set)
+```
+Xor creates a new symmetric difference S = A ∆ B = (A ∪ B) ∖ (A ∩ B) that
+consists of all elements that belong to either A or B, but not to both.
@@ -0,0 +1,100 @@
+// Copyright 2012 Stefan Nilsson
+//
+// 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 bit
+
+// Note the use of << to create an untyped constant.
+const bitsPerWord = 32 << uint(^uint(0)>>63)
+
+// Implementation-specific size of int and uint in bits.
+const BitsPerWord = bitsPerWord // either 32 or 64
+
+// Implementation-specific integer limit values.
+const (
+	MaxInt  = 1<<(BitsPerWord-1) - 1 // either 1<<31 - 1 or 1<<63 - 1
+	MinInt  = -MaxInt - 1            // either -1 << 31 or -1 << 63
+	MaxUint = 1<<BitsPerWord - 1     // either 1<<32 - 1 or 1<<64 - 1
+)
+
+// MinPos returns the position of the minimum nonzero bit in w, w ≠ 0.
+// It panics for w = 0.
+func MinPos(w uint64) int {
+	// “Using de Bruijn Sequences to Index a 1 in a Computer Word”,
+	// Leiserson, Prokop, and Randall, MIT, 1998.
+	if w == 0 {
+		panic("bit: MinPos(0) undefined")
+	}
+
+	// w & -w clears all bits except the one at minimum position p.
+	// Hence, the multiplication below is equivalent to b26<<p.
+	// A table lookup translates the 64 possible outcomes into
+	// the exptected answer.
+	return bitPos[((w&-w)*b26)>>58]
+}
+
+// A sequence, starting with 6 zeros, that contains all possible
+// 6-bit patterns as subseqences, a.k.a. De Bruijn B(2, 6).
+const b26 uint64 = 0x022fdd63cc95386d
+
+var bitPos [64]int
+
+func init() {
+	for p := uint(0); p < 64; p++ {
+		bitPos[b26<<p>>58] = int(p)
+	}
+}
+
+// MaxPos returns the position of the maximum nonzero bit in w, w ≠ 0.
+// It panics for w = 0.
+func MaxPos(w uint64) int {
+	if w == 0 {
+		panic("bit: MaxPos(0) undefined")
+	}
+
+	// Fill word with ones on the right, e.g. 0x0000f308 -> 0x0000ffff.
+	w |= w >> 1
+	w |= w >> 2
+	w |= w >> 4
+	w |= w >> 8
+	w |= w >> 16
+	w |= w >> 32
+	return Count(w) - 1
+}
+
+// Count returns the number of nonzero bits in w.
+func Count(w uint64) int {
+	// “Software Optimization Guide for AMD64 Processors”, Section 8.6.
+	const maxw = 1<<64 - 1
+	const bpw = 64
+
+	// Compute the count for each 2-bit group.
+	// Example using 16-bit word w = 00,01,10,11,00,01,10,11
+	// w - (w>>1) & 01,01,01,01,01,01,01,01 = 00,01,01,10,00,01,01,10
+	w -= (w >> 1) & (maxw / 3)
+
+	// Add the count of adjacent 2-bit groups and store in 4-bit groups:
+	// w & 0011,0011,0011,0011 + w>>2 & 0011,0011,0011,0011 = 0001,0011,0001,0011
+	w = w&(maxw/15*3) + (w>>2)&(maxw/15*3)
+
+	// Add the count of adjacent 4-bit groups and store in 8-bit groups:
+	// (w + w>>4) & 00001111,00001111 = 00000100,00000100
+	w += w >> 4
+	w &= maxw / 255 * 15
+
+	// Add all 8-bit counts with a multiplication and a shift:
+	// (w * 00000001,00000001) >> 8 = 00001000
+	w *= maxw / 255
+	w >>= (bpw/8 - 1) * 8
+	return int(w)
+}
@@ -0,0 +1,890 @@
+// Copyright 2012 Stefan Nilsson
+//
+// 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 bit provides a bitset implementation and utility bit functions for uint64 words.
+package bit
+
+import (
+	"bytes"
+	"strconv"
+)
+
+const (
+	bpw   = 64         // bits per word
+	maxw  = 1<<bpw - 1 // maximum value for a word
+	shift = 6
+	mask  = 0x3f
+)
+
+// Set represents a mutable set of non-negative integers.
+// The zero value of Set is an empty set ready to use.
+// A set occupies approximately n bits, where n is the maximum
+// value that has been stored in the set.
+type Set struct {
+	// Invariants:
+	//	• data[n>>shift] & (1<<(n&mask)) == 1 iff n belongs to set,
+	// 	• data[i] == 0 for all i such that len(data) ≤ i < cap(data),
+	//	• len(data) == 0 if set is empty,
+	//	• data[len(data)-1] != 0 if set is nonempty,
+	//	• min is the minimum element of a nonempty set, 0 otherwise.
+	data []uint64
+	min  int
+}
+
+// New creates a new set S with the given elements.
+func New(n ...int) (S *Set) {
+	if len(n) == 0 {
+		return new(Set)
+	}
+
+	min, max := n[0], n[0]
+	for _, e := range n {
+		switch {
+		case e > max:
+			max = e
+		case e < min:
+			min = e
+		}
+	}
+
+	S = &Set{
+		data: make([]uint64, max>>shift+1),
+		min:  min,
+	}
+
+	for _, e := range n {
+		S.data[e>>shift] |= 1 << uint(e&mask)
+	}
+	return
+}
+
+// Add adds n to S, setting S to S ∪ {n}, and returns the updated set.
+func (S *Set) Add(n int) *Set {
+	if n < 0 {
+		panic("Set: Add(" + strconv.Itoa(n) + ") index out of range")
+	}
+
+	if len(S.data) == 0 || n < S.min {
+		S.min = n
+	}
+
+	i := n >> shift
+	if i >= len(S.data) {
+		S.resize(i + 1)
+	}
+	S.data[i] |= 1 << uint(n&mask)
+	return S
+}
+
+// AddRange adds all integers between m and n-1, m ≤ n,
+// setting S to S ∪ {m..n-1}, and returns the updated set.
+func (S *Set) AddRange(m, n int) *Set {
+	if m == n && m >= 0 {
+		return S
+	}
+
+	if m > n || m < 0 {
+		panic("Set: AddRange(" + strconv.Itoa(m) + ", " + strconv.Itoa(n) + ") bounds out of range")
+	}
+
+	if len(S.data) == 0 || m < S.min {
+		S.min = m
+	}
+
+	n--
+	low, high := m>>shift, n>>shift
+	if high >= len(S.data) {
+		S.resize(high + 1)
+	}
+
+	d := S.data
+	if low == high { // Range fits in one word.
+		d[low] |= bitMask(m&mask, n&mask)
+	} else { // Range spans at least two words.
+		d[low] |= bitMask(m&mask, bpw-1)
+		for i := low + 1; i < high; i++ {
+			d[i] = maxw
+		}
+		d[high] |= bitMask(0, n&mask)
+	}
+	return S
+}
+
+// Remove removes n from S, setting S to S ∖ {n}, and returns the updated set.
+func (S *Set) Remove(n int) *Set {
+	if n < 0 {
+		panic("Set: Remove(" + strconv.Itoa(n) + ") index out of range")
+	}
+
+	if n < S.min {
+		return S
+	}
+
+	i := n >> shift
+	if i >= len(S.data) {
+		return S
+	}
+
+	S.data[i] &^= 1 << uint(n&mask)
+	S.trim()
+
+	if n == S.min {
+		S.min = findMinFrom(S.min, S.data)
+	}
+	return S
+}
+
+// RemoveMin removes the minimum element from S, setting S to S ∖ {min},
+// and returns min. It panics if S is empty.
+func (S *Set) RemoveMin() (min int) {
+	if len(S.data) == 0 {
+		panic("Set: RemoveMin not defined for empty set")
+	}
+
+	min = S.min
+	i := min >> shift
+	d := S.data
+
+	d[i] &^= 1 << uint(min&mask)
+
+	if d[i] != 0 || i+1 < len(d) { // There are more elements left.
+		S.min = findMinFrom(min, d)
+	} else {
+		S.Clear() // The array contains only zeroes.
+	}
+	return
+}
+
+// RemoveMax removes the maximum element from S, setting S to S ∖ {max},
+// and returns max. It panics if S is empty.
+func (S *Set) RemoveMax() (max int) {
+	if len(S.data) == 0 {
+		panic("Set: RemoveMax not defined for empty set")
+	}
+
+	d := S.data
+	i := len(d) - 1
+	w := d[i]
+
+	max = i<<shift + MaxPos(w)
+	d[i] &^= 1 << uint(max&mask)
+	S.trim()
+
+	return
+}
+
+// Min returns the minimum element of the set. It panics if S is empty.
+func (S *Set) Min() int {
+	if len(S.data) == 0 {
+		panic("Set: Min not defined for empty set")
+	}
+
+	return S.min
+}
+
+// Max returns the maximum element of the set. It panics if S is empty.
+func (S *Set) Max() int {
+	if len(S.data) == 0 {
+		panic("Set: Max not defined for empty set")
+	}
+
+	d := S.data
+	i := len(d) - 1
+	w := d[i]
+	return i<<shift + MaxPos(w)
+}
+
+// Next returns (n, true), where n is the smallest element of S such that m < n,
+// or (0, false) if no such element exists.
+func (S *Set) Next(m int) (n int, found bool) {
+	d := S.data
+	len := len(d)
+
+	if len == 0 {
+		return
+	}
+
+	if min := S.min; m < min {
+		return min, true
+	}
+
+	i := len - 1
+	if max := i<<shift + MaxPos(d[i]); m >= max {
+		return
+	}
+
+	i = m >> shift
+	s := 1 + uint(m&mask)
+	w := d[i] >> s << s // Zero out bits for numbers ≤ m.
+	for w == 0 {
+		i++
+		w = d[i]
+	}
+	return i<<shift + MinPos(w), true
+}
+
+// Previous returns (n, true), where n is the largest element of S such that n < m,
+// or (0, false) if no such element exists.
+func (S *Set) Previous(m int) (n int, found bool) {
+	d := S.data
+	len := len(d)
+
+	if len == 0 || m <= S.min {
+		return
+	}
+
+	i := len - 1
+	if max := i<<shift + MaxPos(d[i]); m > max {
+		return max, true
+	}
+
+	i = m >> shift
+	s := bpw - uint(m&mask)
+	w := d[i] << s >> s // Zero out bits for numbers ≥ m.
+	for w == 0 {
+		i--
+		w = d[i]
+	}
+	return i<<shift + MaxPos(w), true
+}
+
+// RemoveRange removes all integers between m and n-1, m ≤ n,
+// setting S to S ∖ {m..n-1}, and returns the updated set.
+func (S *Set) RemoveRange(m, n int) *Set {
+	if m == n && m >= 0 {
+		return S
+	}
+
+	if m > n || m < 0 {
+		panic("Set: RemoveRange(" + strconv.Itoa(m) + ", " + strconv.Itoa(n) + ") bounds out of range")
+	}
+
+	n--
+	d := S.data
+	low, high := m>>shift, n>>shift
+
+	// Range does not intersect S.
+	if n < S.min || low >= len(d) {
+		return S
+	}
+
+	// Bottom of range undershoots S.
+	if m < S.min {
+		low = S.min >> shift // low ≤ high still holds, since S.min ≤ n.
+		m = 0                // To assure that m&mask == 0 below.
+	}
+
+	// Top of range overshoots S.
+	if len(d) <= high {
+		high = len(d) - 1 // low ≤ high still holds, since low < len(d).
+		n = bpw - 1       // To assure that n&mask == bpw-1 below.
+	}
+
+	if low == high { // Range fits in one word
+		d[low] &^= bitMask(m&mask, n&mask)
+	} else { // Range spans at least two words
+		d[low] &^= bitMask(m&mask, bpw-1)
+		for i := low + 1; i < high; i++ {
+			d[i] = 0
+		}
+		d[high] &^= bitMask(0, n&mask)
+	}
+	S.trim()
+
+	if m <= S.min {
+		S.min = findMinFrom(S.min, S.data)
+	}
+	return S
+}
+
+// Clear removes all elements and returns the updated empty set.
+func (S *Set) Clear() *Set {
+	S.realloc(0)
+	S.min = 0
+	return S
+}
+
+// Flip removes n from S if it is present, otherwise it adds n,
+// setting S to S ∆ {n}, and returns the updated set.
+func (S *Set) Flip(n int) *Set {
+	if n < 0 {
+		panic("Set: Flip(" + strconv.Itoa(n) + ") index out of range")
+	}
+
+	if len(S.data) == 0 { // Set correct minimum when S empty.
+		S.min = n
+	}
+
+	i := n >> shift
+	if i >= len(S.data) {
+		S.resize(i + 1)
+	}
+	S.data[i] ^= 1 << uint(n&mask)
+	S.trim()
+
+	if n <= S.min {
+		// If flip removed S.min, we must search for a new minimum.
+		// If n < S.min, the search will find n right away.
+		S.min = findMinFrom(n, S.data)
+	}
+	return S
+}
+
+// FlipRange flips all elements in the range m..n-1, m ≤ n,
+// setting S to S ∆ {m..n-1}, and returns the updated set.
+func (S *Set) FlipRange(m, n int) *Set {
+	if m == n && m >= 0 {
+		return S
+	}
+
+	if m > n || m < 0 {
+		panic("Set: FlipRange(" + strconv.Itoa(m) + ", " + strconv.Itoa(n) + ") bounds out of range")
+	}
+
+	d := S.data
+	if len(d) == 0 { // Set correct minimum when S empty.
+		S.min = m
+	}
+
+	n--
+	low, high := m>>shift, n>>shift
+	if high >= len(d) {
+		S.resize(high + 1)
+		d = S.data
+	}
+
+	if low == high { // Range fits in one word.
+		d[low] ^= bitMask(m&mask, n&mask)
+	} else { // Range spans at least two words.
+		d[low] ^= bitMask(m&mask, bpw-1)
+		for i := low + 1; i < high; i++ {
+			d[i] ^= maxw
+		}
+		d[high] ^= bitMask(0, n&mask)
+	}
+	S.trim()
+
+	// If S.min < m, the minimum does not change.
+	if m <= S.min {
+		// The new minimum can't be smaller than m.
+		S.min = findMinFrom(m, S.data)
+	}
+	return S
+}
+
+// Contains returns true if n, n ≥ 0, is an element of S.
+func (S *Set) Contains(n int) bool {
+	d := S.data
+	i := n >> shift
+
+	if i >= len(d) {
+		return false
+	}
+	return d[i]&(1<<uint(n&mask)) != 0
+}
+
+// Size returns |S|, the number of elements in S.
+// This method scans the set. To check if a set is empty,
+// consider using the more efficient IsEmpty.
+func (S *Set) Size() int {
+	d := S.data
+
+	n := 0
+	for i, l := S.min>>shift, len(d); i < l; i++ {
+		if w := d[i]; w != 0 {
+			n += Count(w)
+		}
+	}
+	return n
+}
+
+// IsEmpty returns true if S = ∅.
+func (S *Set) IsEmpty() bool {
+	return len(S.data) == 0
+}
+
+// Equals returns true if A and B contain the same elements.
+func (A *Set) Equals(B *Set) bool {
+	if A == B {
+		return true
+	}
+
+	if A.min != B.min {
+		return false
+	}
+
+	a, b := A.data, B.data
+	if len(a) != len(b) {
+		return false
+	}
+
+	for i, l := A.min>>shift, len(a); i < l; i++ {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// SubsetOf returns true if A ⊆ B.
+func (A *Set) SubsetOf(B *Set) bool {
+	if A == B {
+		return true
+	}
+
+	a, b := A.data, B.data
+	if len(a) > len(b) {
+		return false
+	}
+
+	if len(a) != 0 && A.min < B.min {
+		return false
+	}
+
+	for i, l := A.min>>shift, len(a); i < l; i++ {
+		if a[i]&^b[i] != 0 {
+			return false
+		}
+	}
+	return true
+}
+
+// Intersects returns true if A and B overlap, i.e. A ∩ B ≠ ∅.
+func (A *Set) Intersects(B *Set) bool {
+	a, b := A.data, B.data
+
+	if len(a) == 0 || len(b) == 0 {
+		return false
+	}
+
+	if A == B { // Notice that both sets are nonempty.
+		return true
+	}
+
+	m := min(len(a), len(b))
+	for i := max(A.min, B.min) >> shift; i < m; i++ {
+		if a[i]&b[i] != 0 {
+			return true
+		}
+	}
+	return false
+}
+
+// And creates a new intersection S = A ∩ B that consists of all
+// elements that belong to both A and B.
+func (A *Set) And(B *Set) (S *Set) {
+	return new(Set).SetAnd(A, B)
+}
+
+// Or creates a new union S = A ∪ B that contains all
+// elements that belong to either A or B.
+func (A *Set) Or(B *Set) (S *Set) {
+	return new(Set).SetOr(A, B)
+}
+
+// AndNot creates a new set difference S = A ∖ B that
+// consists of all elements that belong to A, but not to B.
+func (A *Set) AndNot(B *Set) (S *Set) {
+	return new(Set).SetAndNot(A, B)
+}
+
+// Xor creates a new symmetric difference S = A ∆ B = (A ∪ B) ∖ (A ∩ B)
+// that consists of all elements that belong to either A or B, but not to both.
+func (A *Set) Xor(B *Set) (S *Set) {
+	return new(Set).SetXor(A, B)
+}
+
+// SetWord interprets w as a bitset with numbers in the range 64i to 64i + 63,
+// where 0 ≤ i ≤ ⌊MaxInt/64⌋, overwrites this range in S with w, and returns S.
+func (S *Set) SetWord(i int, w uint64) *Set {
+	if i > MaxInt/64 {
+		panic("Set: SetWord(" + strconv.Itoa(i) + ", 0x" + strconv.FormatUint(w, 16) +
+			") index out of range")
+	}
+
+	if w == 0 && i >= len(S.data) {
+		return S
+	}
+
+	if len := len(S.data); i >= len {
+		if len == 0 { // Set tentative minimum when S is empty.
+			S.min = 64 * i
+		}
+		S.resize(i + 1)
+	}
+
+	S.data[i] = w
+
+	if w == 0 && i == len(S.data)-1 {
+		S.trim()
+	}
+
+	if mi := S.min >> shift; i < mi && w != 0 || i == mi {
+		S.min = findMinFrom(64*i, S.data)
+	}
+	return S
+}
+
+// Word returns the range 64i to 64i + 63 of S as a bitset represented by w.
+func (S *Set) Word(i int) (w uint64) {
+	if i < len(S.data) {
+		w = S.data[i]
+	}
+	return
+}
+
+// Set sets S to A and returns S.
+func (S *Set) Set(A *Set) *Set {
+	S.realloc(len(A.data))
+	low := min(A.min>>shift, S.min>>shift) // Words below this index are all zero,
+	copy(S.data[low:], A.data[low:])       // so there is no need to copy them.
+	S.min = A.min
+	return S
+}
+
+// SetAnd sets S to the intersection A ∩ B and returns S.
+func (S *Set) SetAnd(A, B *Set) *Set {
+	a, b := A.data, B.data
+	la, lb := len(a), len(b)
+	ma, mb, ms := A.min, B.min, S.min
+
+	// Check if ranges overlap.
+	if la == 0 || lb == 0 || la <= mb>>shift || lb <= ma>>shift {
+		return S.Clear()
+	}
+
+	// S.data[i], i < low, are words that should be zero and already are.
+	low := min(max(ma, mb), ms) >> shift
+
+	// Find last nonzero word in result.
+	i := min(la, lb) - 1
+	for i >= 0 && a[i]&b[i] == 0 {
+		i--
+	}
+	if S == A || S == B {
+		S.resize(i + 1)
+	} else {
+		S.realloc(i + 1)
+	}
+
+	for ; i >= low; i-- {
+		S.data[i] = a[i] & b[i]
+	}
+
+	S.min = findMinFrom(max(ma, mb), S.data)
+	return S
+}
+
+// SetAndNot sets S to the set difference A ∖ B and returns S.
+func (S *Set) SetAndNot(A, B *Set) *Set {
+	a, b := A.data, B.data
+	la, lb := len(a), len(b)
+	ma, mb, ms := A.min, B.min, S.min
+
+	// Check if ranges overlap.
+	if la == 0 || lb == 0 || la <= mb>>shift || lb <= ma>>shift {
+		return S.Set(A)
+	}
+
+	// S.data[i], i < low, are words that should be zero and already are.
+	low := min(ma, ms) >> shift
+
+	// Result requires len(a) words if len(a) > len(b),
+	// otherwise find last nonzero word in result.
+	i := la - 1
+	if la <= lb {
+		for i >= 0 && a[i]&^b[i] == 0 {
+			i--
+		}
+	}
+	if S == A || S == B {
+		S.resize(i + 1)
+	} else {
+		S.realloc(i + 1)
+	}
+
+	d := S.data
+	if m := max(lb, low); m <= i {
+		copy(d[m:i+1], a[m:i+1])
+		i = m - 1
+	}
+
+	for ; i >= low; i-- {
+		d[i] = a[i] &^ b[i]
+	}
+
+	if A.min < B.min { // Minimum can't have changed.
+		S.min = A.min
+	} else {
+		S.min = findMinFrom(ma, d) // can't be smaller than previous A.min.
+	}
+	return S
+}
+
+// SetOr sets S to the union A ∪ B and returns S.
+func (S *Set) SetOr(A, B *Set) *Set {
+	// Swap, if necessary, to make A shorter than B.
+	if len(A.data) > len(B.data) {
+		A, B = B, A
+	}
+	a, b := A.data, B.data
+	la, lb := len(a), len(b)
+	ma, mb, ms := A.min, B.min, S.min
+
+	i := lb - 1
+	if S == A || S == B {
+		S.resize(i + 1)
+	} else {
+		S.realloc(i + 1)
+	}
+
+	d := S.data
+	copy(d[la:i+1], b[la:i+1])
+	i = la - 1
+
+	// S.data[i], i < low, are words that should be zero and already are.
+	low := min(min(ma, mb), ms) >> shift
+	for ; i >= low; i-- {
+		d[i] = a[i] | b[i]
+	}
+
+	if la == 0 {
+		S.min = mb
+	} else if lb == 0 {
+		S.min = ma
+	} else {
+		S.min = min(ma, mb)
+	}
+	return S
+}
+
+// SetXor sets S to the symmetric difference A ∆ B = (A ∪ B) ∖ (A ∩ B)
+// and returns S.
+func (S *Set) SetXor(A, B *Set) *Set {
+	// Swap, if necessary, to make A shorter than B.
+	if len(A.data) > len(B.data) {
+		A, B = B, A
+	}
+	a, b := A.data, B.data
+	la, lb := len(a), len(b)
+	ma, mb, ms := A.min, B.min, S.min
+
+	i := lb - 1
+	if la == lb { // The only case where result may be shorter than len(b).
+		low := min(ma, mb) >> shift
+		for i >= low && a[i]^b[i] == 0 {
+			i--
+		}
+		if i == low-1 { // Only zero elements left.
+			return S.Clear()
+		}
+	}
+
+	if S == A || S == B {
+		S.resize(i + 1)
+	} else {
+		S.realloc(i + 1)
+	}
+
+	d := S.data
+	if la <= i {
+		copy(d[la:i+1], b[la:i+1])
+		i = la - 1
+	}
+
+	// S.data[i], i < low, are words that should be zero and already are.
+	low := min(min(ma, mb), ms) >> shift
+	for ; i >= low; i-- {
+		d[i] = a[i] ^ b[i]
+	}
+
+	S.min = findMinFrom(min(ma, mb), d)
+	return S
+}
+
+// Do calls function f for each element n ∊ S in numerical order.
+// It is safe for f to add or remove elements e, e ≤ n, from S.
+// The behavior of Do is undefined if f changes the set in any other way.
+func (S *Set) Do(f func(n int)) {
+	d := S.data
+
+	for i, l := S.min>>shift, len(d); i < l; i++ {
+		w := d[i]
+		if w == 0 {
+			continue
+		}
+		n := i << shift // element represented by w&1
+		for w != 0 {
+			b := MinPos(w)
+			n += b
+			f(n)
+			n++
+			w >>= uint(b + 1)
+			for w&1 != 0 { // common case
+				f(n)
+				n++
+				w >>= 1
+			}
+		}
+	}
+}
+
+// String returns a string representation of S.
+// The elements are listed in ascending order, enclosed by braces,
+// and separated by ", ". Runs of at least three elements a, a+1, ..., b
+// are given as "a..b".
+//
+// For example, the set {1, 2, 6, 5, 3} is represented as "{1..3, 5, 6}".
+func (S *Set) String() string {
+	sb := new(bytes.Buffer)
+	sb.WriteString("{")
+
+	a, b := -1, -2 // keeps track of a range a..b of elements
+	S.Do(func(n int) {
+		if n == b+1 { // Increase current range from a..b to a..b+1.
+			b = n
+			return
+		}
+		writeRange(sb, a, b)
+		a, b = n, n // Start new range.
+	})
+	writeRange(sb, a, b)
+
+	if S.Size() > 0 {
+		sb.Truncate(sb.Len() - 2) // Remove trailing ", ".
+	}
+	sb.WriteString("}")
+	return sb.String()
+}
+
+// writeRange writes either "", "a", "a, b, " or "a..b, " to buffer.
+func writeRange(sb *bytes.Buffer, a, b int) {
+	switch {
+	case a > b:
+		// sb.WriteString(sb, "")
+	case a == b:
+		sb.WriteString(strconv.Itoa(a))
+		sb.WriteString(", ")
+	case a+1 == b:
+		sb.WriteString(strconv.Itoa(a))
+		sb.WriteString(", ")
+		sb.WriteString(strconv.Itoa(b))
+		sb.WriteString(", ")
+	default:
+		sb.WriteString(strconv.Itoa(a))
+		sb.WriteString("..")
+		sb.WriteString(strconv.Itoa(b))
+		sb.WriteString(", ")
+	}
+}
+
+// resize changes the length of S.data to n, keeping old values.
+// It preserves the invariant S.data[i] = 0, n ≤ i < cap(data).
+func (S *Set) resize(n int) {
+	d := S.data
+
+	if S.realloc(n) {
+		low := min(S.min>>shift, len(d)) // Words below S.min>>shift are zero;
+		copy(S.data[low:], d[low:])      // there is no need to copy them.
+	}
+}
+
+// realloc creates a slice S.data of length n, possibly zeroing out old values.
+// It preserves the invariant S.data[i] = 0, n ≤ i < cap(data).
+// It returns true if new memory has been allocated.
+func (S *Set) realloc(n int) (didAlloc bool) {
+	if c := cap(S.data); c < n {
+		S.data = make([]uint64, n, newCap(n, c))
+		return true
+	}
+
+	// Add zeroes if shrinking.
+	d := S.data
+	low := max(n, S.min>>shift) // The words d[i], i < low, are already zero.
+	for i := len(d) - 1; i >= low; i-- {
+		d[i] = 0
+	}
+	S.data = d[:n]
+	return false
+}
+
+// newCap suggests a new increased capacity, favoring powers of two,
+// when growing a slice to length n. The suggested capacities guarantee
+// linear amortized cost for repeated memory allocations.
+func newCap(n, prevCap int) int {
+	return max(n, nextPow2(prevCap))
+}
+
+// nextPow2 returns the smallest p = 1, 2, 4, ..., 2^k such that p > n,
+// or MaxInt if p > MaxInt.
+func nextPow2(n int) (p int) {
+	if n <= 0 {
+		return 1
+	}
+
+	if k := MaxPos(uint64(n)) + 1; k < BitsPerWord-1 {
+		return 1 << uint(k)
+	}
+	return MaxInt
+}
+
+// trim slices S.data by removing all trailing words equal to zero.
+// It preserves the invariant: S.min = min(S) if S ≠ ∅, 0 otherwise.
+func (S *Set) trim() {
+	d := S.data
+	i := len(d) - 1
+	for i >= 0 && d[i] == 0 {
+		i--
+	}
+	S.data = d[:i+1]
+	if i == -1 {
+		S.min = 0
+	}
+}
+
+// findMinFrom finds the mininum element starting the search from n.
+// It assumes that such an element exists; however, it returns 0 if
+// len(data) == 0.
+func findMinFrom(n int, data []uint64) int {
+	if len(data) == 0 {
+		return 0
+	}
+
+	i := n >> shift
+	w := data[i]
+	for w == 0 {
+		i++
+		w = data[i]
+	}
+	return i<<shift + MinPos(w)
+}
+
+// bitMask returns a bit mask with nonzero bits from m to n, 0 ≤ m ≤ n < bpw.
+func bitMask(m, n int) uint64 {
+	return maxw >> uint(bpw-1-(n-m)) << uint(m)
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
@@ -0,0 +1,22 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
@@ -0,0 +1,4 @@
+language: go
+go:
+  - 1.1
+  - tip
@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Armon Dadgar
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
@@ -0,0 +1,45 @@
+go-socks5 [![Build Status](https://travis-ci.org/armon/go-socks5.png)](https://travis-ci.org/armon/go-socks5)
+=========
+
+Provides the `socks5` package that implements a [SOCKS5 server](http://en.wikipedia.org/wiki/SOCKS).
+SOCKS (Secure Sockets) is used to route traffic between a client and server through
+an intermediate proxy layer. This can be used to bypass firewalls or NATs.
+
+Feature
+=======
+
+The package has the following features:
+* "No Auth" mode
+* User/Password authentication
+* Support for the CONNECT command
+* Rules to do granular filtering of commands
+* Custom DNS resolution
+* Unit tests
+
+TODO
+====
+
+The package still needs the following:
+* Support for the BIND command
+* Support for the ASSOCIATE command
+
+
+Example
+=======
+
+Below is a simple example of usage
+
+```go
+// Create a SOCKS5 server
+conf := &socks5.Config{}
+server, err := socks5.New(conf)
+if err != nil {
+  panic(err)
+}
+
+// Create SOCKS5 proxy on localhost port 8000
+if err := server.ListenAndServe("tcp", "127.0.0.1:8000"); err != nil {
+  panic(err)
+}
+```
+
@@ -0,0 +1,151 @@
+package socks5
+
+import (
+	"fmt"
+	"io"
+)
+
+const (
+	NoAuth          = uint8(0)
+	noAcceptable    = uint8(255)
+	UserPassAuth    = uint8(2)
+	userAuthVersion = uint8(1)
+	authSuccess     = uint8(0)
+	authFailure     = uint8(1)
+)
+
+var (
+	UserAuthFailed  = fmt.Errorf("User authentication failed")
+	NoSupportedAuth = fmt.Errorf("No supported authentication mechanism")
+)
+
+// A Request encapsulates authentication state provided
+// during negotiation
+type AuthContext struct {
+	// Provided auth method
+	Method uint8
+	// Payload provided during negotiation.
+	// Keys depend on the used auth method.
+	// For UserPassauth contains Username
+	Payload map[string]string
+}
+
+type Authenticator interface {
+	Authenticate(reader io.Reader, writer io.Writer) (*AuthContext, error)
+	GetCode() uint8
+}
+
+// NoAuthAuthenticator is used to handle the "No Authentication" mode
+type NoAuthAuthenticator struct{}
+
+func (a NoAuthAuthenticator) GetCode() uint8 {
+	return NoAuth
+}
+
+func (a NoAuthAuthenticator) Authenticate(reader io.Reader, writer io.Writer) (*AuthContext, error) {
+	_, err := writer.Write([]byte{socks5Version, NoAuth})
+	return &AuthContext{NoAuth, nil}, err
+}
+
+// UserPassAuthenticator is used to handle username/password based
+// authentication
+type UserPassAuthenticator struct {
+	Credentials CredentialStore
+}
+
+func (a UserPassAuthenticator) GetCode() uint8 {
+	return UserPassAuth
+}
+
+func (a UserPassAuthenticator) Authenticate(reader io.Reader, writer io.Writer) (*AuthContext, error) {
+	// Tell the client to use user/pass auth
+	if _, err := writer.Write([]byte{socks5Version, UserPassAuth}); err != nil {
+		return nil, err
+	}
+
+	// Get the version and username length
+	header := []byte{0, 0}
+	if _, err := io.ReadAtLeast(reader, header, 2); err != nil {
+		return nil, err
+	}
+
+	// Ensure we are compatible
+	if header[0] != userAuthVersion {
+		return nil, fmt.Errorf("Unsupported auth version: %v", header[0])
+	}
+
+	// Get the user name
+	userLen := int(header[1])
+	user := make([]byte, userLen)
+	if _, err := io.ReadAtLeast(reader, user, userLen); err != nil {
+		return nil, err
+	}
+
+	// Get the password length
+	if _, err := reader.Read(header[:1]); err != nil {
+		return nil, err
+	}
+
+	// Get the password
+	passLen := int(header[0])
+	pass := make([]byte, passLen)
+	if _, err := io.ReadAtLeast(reader, pass, passLen); err != nil {
+		return nil, err
+	}
+
+	// Verify the password
+	if a.Credentials.Valid(string(user), string(pass)) {
+		if _, err := writer.Write([]byte{userAuthVersion, authSuccess}); err != nil {
+			return nil, err
+		}
+	} else {
+		if _, err := writer.Write([]byte{userAuthVersion, authFailure}); err != nil {
+			return nil, err
+		}
+		return nil, UserAuthFailed
+	}
+
+	// Done
+	return &AuthContext{UserPassAuth, map[string]string{"Username": string(user)}}, nil
+}
+
+// authenticate is used to handle connection authentication
+func (s *Server) authenticate(conn io.Writer, bufConn io.Reader) (*AuthContext, error) {
+	// Get the methods
+	methods, err := readMethods(bufConn)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to get auth methods: %v", err)
+	}
+
+	// Select a usable method
+	for _, method := range methods {
+		cator, found := s.authMethods[method]
+		if found {
+			return cator.Authenticate(bufConn, conn)
+		}
+	}
+
+	// No usable method found
+	return nil, noAcceptableAuth(conn)
+}
+
+// noAcceptableAuth is used to handle when we have no eligible
+// authentication mechanism
+func noAcceptableAuth(conn io.Writer) error {
+	conn.Write([]byte{socks5Version, noAcceptable})
+	return NoSupportedAuth
+}
+
+// readMethods is used to read the number of methods
+// and proceeding auth methods
+func readMethods(r io.Reader) ([]byte, error) {
+	header := []byte{0}
+	if _, err := r.Read(header); err != nil {
+		return nil, err
+	}
+
+	numMethods := int(header[0])
+	methods := make([]byte, numMethods)
+	_, err := io.ReadAtLeast(r, methods, numMethods)
+	return methods, err
+}
@@ -0,0 +1,17 @@
+package socks5
+
+// CredentialStore is used to support user/pass authentication
+type CredentialStore interface {
+	Valid(user, password string) bool
+}
+
+// StaticCredentials enables using a map directly as a credential store
+type StaticCredentials map[string]string
+
+func (s StaticCredentials) Valid(user, password string) bool {
+	pass, ok := s[user]
+	if !ok {
+		return false
+	}
+	return password == pass
+}
@@ -0,0 +1,364 @@
+package socks5
+
+import (
+	"fmt"
+	"io"
+	"net"
+	"strconv"
+	"strings"
+
+	"golang.org/x/net/context"
+)
+
+const (
+	ConnectCommand   = uint8(1)
+	BindCommand      = uint8(2)
+	AssociateCommand = uint8(3)
+	ipv4Address      = uint8(1)
+	fqdnAddress      = uint8(3)
+	ipv6Address      = uint8(4)
+)
+
+const (
+	successReply uint8 = iota
+	serverFailure
+	ruleFailure
+	networkUnreachable
+	hostUnreachable
+	connectionRefused
+	ttlExpired
+	commandNotSupported
+	addrTypeNotSupported
+)
+
+var (
+	unrecognizedAddrType = fmt.Errorf("Unrecognized address type")
+)
+
+// AddressRewriter is used to rewrite a destination transparently
+type AddressRewriter interface {
+	Rewrite(ctx context.Context, request *Request) (context.Context, *AddrSpec)
+}
+
+// AddrSpec is used to return the target AddrSpec
+// which may be specified as IPv4, IPv6, or a FQDN
+type AddrSpec struct {
+	FQDN string
+	IP   net.IP
+	Port int
+}
+
+func (a *AddrSpec) String() string {
+	if a.FQDN != "" {
+		return fmt.Sprintf("%s (%s):%d", a.FQDN, a.IP, a.Port)
+	}
+	return fmt.Sprintf("%s:%d", a.IP, a.Port)
+}
+
+// Address returns a string suitable to dial; prefer returning IP-based
+// address, fallback to FQDN
+func (a AddrSpec) Address() string {
+	if 0 != len(a.IP) {
+		return net.JoinHostPort(a.IP.String(), strconv.Itoa(a.Port))
+	}
+	return net.JoinHostPort(a.FQDN, strconv.Itoa(a.Port))
+}
+
+// A Request represents request received by a server
+type Request struct {
+	// Protocol version
+	Version uint8
+	// Requested command
+	Command uint8
+	// AuthContext provided during negotiation
+	AuthContext *AuthContext
+	// AddrSpec of the the network that sent the request
+	RemoteAddr *AddrSpec
+	// AddrSpec of the desired destination
+	DestAddr *AddrSpec
+	// AddrSpec of the actual destination (might be affected by rewrite)
+	realDestAddr *AddrSpec
+	bufConn      io.Reader
+}
+
+type conn interface {
+	Write([]byte) (int, error)
+	RemoteAddr() net.Addr
+}
+
+// NewRequest creates a new Request from the tcp connection
+func NewRequest(bufConn io.Reader) (*Request, error) {
+	// Read the version byte
+	header := []byte{0, 0, 0}
+	if _, err := io.ReadAtLeast(bufConn, header, 3); err != nil {
+		return nil, fmt.Errorf("Failed to get command version: %v", err)
+	}
+
+	// Ensure we are compatible
+	if header[0] != socks5Version {
+		return nil, fmt.Errorf("Unsupported command version: %v", header[0])
+	}
+
+	// Read in the destination address
+	dest, err := readAddrSpec(bufConn)
+	if err != nil {
+		return nil, err
+	}
+
+	request := &Request{
+		Version:  socks5Version,
+		Command:  header[1],
+		DestAddr: dest,
+		bufConn:  bufConn,
+	}
+
+	return request, nil
+}
+
+// handleRequest is used for request processing after authentication
+func (s *Server) handleRequest(req *Request, conn conn) error {
+	ctx := context.Background()
+
+	// Resolve the address if we have a FQDN
+	dest := req.DestAddr
+	if dest.FQDN != "" {
+		ctx_, addr, err := s.config.Resolver.Resolve(ctx, dest.FQDN)
+		if err != nil {
+			if err := sendReply(conn, hostUnreachable, nil); err != nil {
+				return fmt.Errorf("Failed to send reply: %v", err)
+			}
+			return fmt.Errorf("Failed to resolve destination '%v': %v", dest.FQDN, err)
+		}
+		ctx = ctx_
+		dest.IP = addr
+	}
+
+	// Apply any address rewrites
+	req.realDestAddr = req.DestAddr
+	if s.config.Rewriter != nil {
+		ctx, req.realDestAddr = s.config.Rewriter.Rewrite(ctx, req)
+	}
+
+	// Switch on the command
+	switch req.Command {
+	case ConnectCommand:
+		return s.handleConnect(ctx, conn, req)
+	case BindCommand:
+		return s.handleBind(ctx, conn, req)
+	case AssociateCommand:
+		return s.handleAssociate(ctx, conn, req)
+	default:
+		if err := sendReply(conn, commandNotSupported, nil); err != nil {
+			return fmt.Errorf("Failed to send reply: %v", err)
+		}
+		return fmt.Errorf("Unsupported command: %v", req.Command)
+	}
+}
+
+// handleConnect is used to handle a connect command
+func (s *Server) handleConnect(ctx context.Context, conn conn, req *Request) error {
+	// Check if this is allowed
+	if ctx_, ok := s.config.Rules.Allow(ctx, req); !ok {
+		if err := sendReply(conn, ruleFailure, nil); err != nil {
+			return fmt.Errorf("Failed to send reply: %v", err)
+		}
+		return fmt.Errorf("Connect to %v blocked by rules", req.DestAddr)
+	} else {
+		ctx = ctx_
+	}
+
+	// Attempt to connect
+	dial := s.config.Dial
+	if dial == nil {
+		dial = func(ctx context.Context, net_, addr string) (net.Conn, error) {
+			return net.Dial(net_, addr)
+		}
+	}
+	target, err := dial(ctx, "tcp", req.realDestAddr.Address())
+	if err != nil {
+		msg := err.Error()
+		resp := hostUnreachable
+		if strings.Contains(msg, "refused") {
+			resp = connectionRefused
+		} else if strings.Contains(msg, "network is unreachable") {
+			resp = networkUnreachable
+		}
+		if err := sendReply(conn, resp, nil); err != nil {
+			return fmt.Errorf("Failed to send reply: %v", err)
+		}
+		return fmt.Errorf("Connect to %v failed: %v", req.DestAddr, err)
+	}
+	defer target.Close()
+
+	// Send success
+	local := target.LocalAddr().(*net.TCPAddr)
+	bind := AddrSpec{IP: local.IP, Port: local.Port}
+	if err := sendReply(conn, successReply, &bind); err != nil {
+		return fmt.Errorf("Failed to send reply: %v", err)
+	}
+
+	// Start proxying
+	errCh := make(chan error, 2)
+	go proxy(target, req.bufConn, errCh)
+	go proxy(conn, target, errCh)
+
+	// Wait
+	for i := 0; i < 2; i++ {
+		e := <-errCh
+		if e != nil {
+			// return from this function closes target (and conn).
+			return e
+		}
+	}
+	return nil
+}
+
+// handleBind is used to handle a connect command
+func (s *Server) handleBind(ctx context.Context, conn conn, req *Request) error {
+	// Check if this is allowed
+	if ctx_, ok := s.config.Rules.Allow(ctx, req); !ok {
+		if err := sendReply(conn, ruleFailure, nil); err != nil {
+			return fmt.Errorf("Failed to send reply: %v", err)
+		}
+		return fmt.Errorf("Bind to %v blocked by rules", req.DestAddr)
+	} else {
+		ctx = ctx_
+	}
+
+	// TODO: Support bind
+	if err := sendReply(conn, commandNotSupported, nil); err != nil {
+		return fmt.Errorf("Failed to send reply: %v", err)
+	}
+	return nil
+}
+
+// handleAssociate is used to handle a connect command
+func (s *Server) handleAssociate(ctx context.Context, conn conn, req *Request) error {
+	// Check if this is allowed
+	if ctx_, ok := s.config.Rules.Allow(ctx, req); !ok {
+		if err := sendReply(conn, ruleFailure, nil); err != nil {
+			return fmt.Errorf("Failed to send reply: %v", err)
+		}
+		return fmt.Errorf("Associate to %v blocked by rules", req.DestAddr)
+	} else {
+		ctx = ctx_
+	}
+
+	// TODO: Support associate
+	if err := sendReply(conn, commandNotSupported, nil); err != nil {
+		return fmt.Errorf("Failed to send reply: %v", err)
+	}
+	return nil
+}
+
+// readAddrSpec is used to read AddrSpec.
+// Expects an address type byte, follwed by the address and port
+func readAddrSpec(r io.Reader) (*AddrSpec, error) {
+	d := &AddrSpec{}
+
+	// Get the address type
+	addrType := []byte{0}
+	if _, err := r.Read(addrType); err != nil {
+		return nil, err
+	}
+
+	// Handle on a per type basis
+	switch addrType[0] {
+	case ipv4Address:
+		addr := make([]byte, 4)
+		if _, err := io.ReadAtLeast(r, addr, len(addr)); err != nil {
+			return nil, err
+		}
+		d.IP = net.IP(addr)
+
+	case ipv6Address:
+		addr := make([]byte, 16)
+		if _, err := io.ReadAtLeast(r, addr, len(addr)); err != nil {
+			return nil, err
+		}
+		d.IP = net.IP(addr)
+
+	case fqdnAddress:
+		if _, err := r.Read(addrType); err != nil {
+			return nil, err
+		}
+		addrLen := int(addrType[0])
+		fqdn := make([]byte, addrLen)
+		if _, err := io.ReadAtLeast(r, fqdn, addrLen); err != nil {
+			return nil, err
+		}
+		d.FQDN = string(fqdn)
+
+	default:
+		return nil, unrecognizedAddrType
+	}
+
+	// Read the port
+	port := []byte{0, 0}
+	if _, err := io.ReadAtLeast(r, port, 2); err != nil {
+		return nil, err
+	}
+	d.Port = (int(port[0]) << 8) | int(port[1])
+
+	return d, nil
+}
+
+// sendReply is used to send a reply message
+func sendReply(w io.Writer, resp uint8, addr *AddrSpec) error {
+	// Format the address
+	var addrType uint8
+	var addrBody []byte
+	var addrPort uint16
+	switch {
+	case addr == nil:
+		addrType = ipv4Address
+		addrBody = []byte{0, 0, 0, 0}
+		addrPort = 0
+
+	case addr.FQDN != "":
+		addrType = fqdnAddress
+		addrBody = append([]byte{byte(len(addr.FQDN))}, addr.FQDN...)
+		addrPort = uint16(addr.Port)
+
+	case addr.IP.To4() != nil:
+		addrType = ipv4Address
+		addrBody = []byte(addr.IP.To4())
+		addrPort = uint16(addr.Port)
+
+	case addr.IP.To16() != nil:
+		addrType = ipv6Address
+		addrBody = []byte(addr.IP.To16())
+		addrPort = uint16(addr.Port)
+
+	default:
+		return fmt.Errorf("Failed to format address: %v", addr)
+	}
+
+	// Format the message
+	msg := make([]byte, 6+len(addrBody))
+	msg[0] = socks5Version
+	msg[1] = resp
+	msg[2] = 0 // Reserved
+	msg[3] = addrType
+	copy(msg[4:], addrBody)
+	msg[4+len(addrBody)] = byte(addrPort >> 8)
+	msg[4+len(addrBody)+1] = byte(addrPort & 0xff)
+
+	// Send the message
+	_, err := w.Write(msg)
+	return err
+}
+
+type closeWriter interface {
+	CloseWrite() error
+}
+
+// proxy is used to suffle data from src to destination, and sends errors
+// down a dedicated channel
+func proxy(dst io.Writer, src io.Reader, errCh chan error) {
+	_, err := io.Copy(dst, src)
+	if tcpConn, ok := dst.(closeWriter); ok {
+		tcpConn.CloseWrite()
+	}
+	errCh <- err
+}
@@ -0,0 +1,23 @@
+package socks5
+
+import (
+	"net"
+
+	"golang.org/x/net/context"
+)
+
+// NameResolver is used to implement custom name resolution
+type NameResolver interface {
+	Resolve(ctx context.Context, name string) (context.Context, net.IP, error)
+}
+
+// DNSResolver uses the system DNS to resolve host names
+type DNSResolver struct{}
+
+func (d DNSResolver) Resolve(ctx context.Context, name string) (context.Context, net.IP, error) {
+	addr, err := net.ResolveIPAddr("ip", name)
+	if err != nil {
+		return ctx, nil, err
+	}
+	return ctx, addr.IP, err
+}
@@ -0,0 +1,41 @@
+package socks5
+
+import (
+	"golang.org/x/net/context"
+)
+
+// RuleSet is used to provide custom rules to allow or prohibit actions
+type RuleSet interface {
+	Allow(ctx context.Context, req *Request) (context.Context, bool)
+}
+
+// PermitAll returns a RuleSet which allows all types of connections
+func PermitAll() RuleSet {
+	return &PermitCommand{true, true, true}
+}
+
+// PermitNone returns a RuleSet which disallows all types of connections
+func PermitNone() RuleSet {
+	return &PermitCommand{false, false, false}
+}
+
+// PermitCommand is an implementation of the RuleSet which
+// enables filtering supported commands
+type PermitCommand struct {
+	EnableConnect   bool
+	EnableBind      bool
+	EnableAssociate bool
+}
+
+func (p *PermitCommand) Allow(ctx context.Context, req *Request) (context.Context, bool) {
+	switch req.Command {
+	case ConnectCommand:
+		return ctx, p.EnableConnect
+	case BindCommand:
+		return ctx, p.EnableBind
+	case AssociateCommand:
+		return ctx, p.EnableAssociate
+	}
+
+	return ctx, false
+}
@@ -0,0 +1,169 @@
+package socks5
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"net"
+	"os"
+
+	"golang.org/x/net/context"
+)
+
+const (
+	socks5Version = uint8(5)
+)
+
+// Config is used to setup and configure a Server
+type Config struct {
+	// AuthMethods can be provided to implement custom authentication
+	// By default, "auth-less" mode is enabled.
+	// For password-based auth use UserPassAuthenticator.
+	AuthMethods []Authenticator
+
+	// If provided, username/password authentication is enabled,
+	// by appending a UserPassAuthenticator to AuthMethods. If not provided,
+	// and AUthMethods is nil, then "auth-less" mode is enabled.
+	Credentials CredentialStore
+
+	// Resolver can be provided to do custom name resolution.
+	// Defaults to DNSResolver if not provided.
+	Resolver NameResolver
+
+	// Rules is provided to enable custom logic around permitting
+	// various commands. If not provided, PermitAll is used.
+	Rules RuleSet
+
+	// Rewriter can be used to transparently rewrite addresses.
+	// This is invoked before the RuleSet is invoked.
+	// Defaults to NoRewrite.
+	Rewriter AddressRewriter
+
+	// BindIP is used for bind or udp associate
+	BindIP net.IP
+
+	// Logger can be used to provide a custom log target.
+	// Defaults to stdout.
+	Logger *log.Logger
+
+	// Optional function for dialing out
+	Dial func(ctx context.Context, network, addr string) (net.Conn, error)
+}
+
+// Server is reponsible for accepting connections and handling
+// the details of the SOCKS5 protocol
+type Server struct {
+	config      *Config
+	authMethods map[uint8]Authenticator
+}
+
+// New creates a new Server and potentially returns an error
+func New(conf *Config) (*Server, error) {
+	// Ensure we have at least one authentication method enabled
+	if len(conf.AuthMethods) == 0 {
+		if conf.Credentials != nil {
+			conf.AuthMethods = []Authenticator{&UserPassAuthenticator{conf.Credentials}}
+		} else {
+			conf.AuthMethods = []Authenticator{&NoAuthAuthenticator{}}
+		}
+	}
+
+	// Ensure we have a DNS resolver
+	if conf.Resolver == nil {
+		conf.Resolver = DNSResolver{}
+	}
+
+	// Ensure we have a rule set
+	if conf.Rules == nil {
+		conf.Rules = PermitAll()
+	}
+
+	// Ensure we have a log target
+	if conf.Logger == nil {
+		conf.Logger = log.New(os.Stdout, "", log.LstdFlags)
+	}
+
+	server := &Server{
+		config: conf,
+	}
+
+	server.authMethods = make(map[uint8]Authenticator)
+
+	for _, a := range conf.AuthMethods {
+		server.authMethods[a.GetCode()] = a
+	}
+
+	return server, nil
+}
+
+// ListenAndServe is used to create a listener and serve on it
+func (s *Server) ListenAndServe(network, addr string) error {
+	l, err := net.Listen(network, addr)
+	if err != nil {
+		return err
+	}
+	return s.Serve(l)
+}
+
+// Serve is used to serve connections from a listener
+func (s *Server) Serve(l net.Listener) error {
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			return err
+		}
+		go s.ServeConn(conn)
+	}
+	return nil
+}
+
+// ServeConn is used to serve a single connection.
+func (s *Server) ServeConn(conn net.Conn) error {
+	defer conn.Close()
+	bufConn := bufio.NewReader(conn)
+
+	// Read the version byte
+	version := []byte{0}
+	if _, err := bufConn.Read(version); err != nil {
+		s.config.Logger.Printf("[ERR] socks: Failed to get version byte: %v", err)
+		return err
+	}
+
+	// Ensure we are compatible
+	if version[0] != socks5Version {
+		err := fmt.Errorf("Unsupported SOCKS version: %v", version)
+		s.config.Logger.Printf("[ERR] socks: %v", err)
+		return err
+	}
+
+	// Authenticate the connection
+	authContext, err := s.authenticate(conn, bufConn)
+	if err != nil {
+		err = fmt.Errorf("Failed to authenticate: %v", err)
+		s.config.Logger.Printf("[ERR] socks: %v", err)
+		return err
+	}
+
+	request, err := NewRequest(bufConn)
+	if err != nil {
+		if err == unrecognizedAddrType {
+			if err := sendReply(conn, addrTypeNotSupported, nil); err != nil {
+				return fmt.Errorf("Failed to send reply: %v", err)
+			}
+		}
+		return fmt.Errorf("Failed to read destination address: %v", err)
+	}
+	request.AuthContext = authContext
+	if client, ok := conn.RemoteAddr().(*net.TCPAddr); ok {
+		request.RemoteAddr = &AddrSpec{IP: client.IP, Port: client.Port}
+	}
+
+	// Process the client request
+	if err := s.handleRequest(request, conn); err != nil {
+		err = fmt.Errorf("Failed to handle request: %v", err)
+		s.config.Logger.Printf("[ERR] socks: %v", err)
+		return err
+	}
+
+	return nil
+}
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
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+
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+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
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+   Copyright [yyyy] [name of copyright owner]
+
+   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.
@@ -0,0 +1,3 @@
+AWS SDK for Go
+Copyright 2015 Amazon.com, Inc. or its affiliates. All Rights Reserved. 
+Copyright 2014-2015 Stripe, Inc.
@@ -0,0 +1,145 @@
+// Package awserr represents API error interface accessors for the SDK.
+package awserr
+
+// An Error wraps lower level errors with code, message and an original error.
+// The underlying concrete error type may also satisfy other interfaces which
+// can be to used to obtain more specific information about the error.
+//
+// Calling Error() or String() will always include the full information about
+// an error based on its underlying type.
+//
+// Example:
+//
+//     output, err := s3manage.Upload(svc, input, opts)
+//     if err != nil {
+//         if awsErr, ok := err.(awserr.Error); ok {
+//             // Get error details
+//             log.Println("Error:", awsErr.Code(), awsErr.Message())
+//
+//             // Prints out full error message, including original error if there was one.
+//             log.Println("Error:", awsErr.Error())
+//
+//             // Get original error
+//             if origErr := awsErr.OrigErr(); origErr != nil {
+//                 // operate on original error.
+//             }
+//         } else {
+//             fmt.Println(err.Error())
+//         }
+//     }
+//
+type Error interface {
+	// Satisfy the generic error interface.
+	error
+
+	// Returns the short phrase depicting the classification of the error.
+	Code() string
+
+	// Returns the error details message.
+	Message() string
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErr() error
+}
+
+// BatchError is a batch of errors which also wraps lower level errors with
+// code, message, and original errors. Calling Error() will include all errors
+// that occurred in the batch.
+//
+// Deprecated: Replaced with BatchedErrors. Only defined for backwards
+// compatibility.
+type BatchError interface {
+	// Satisfy the generic error interface.
+	error
+
+	// Returns the short phrase depicting the classification of the error.
+	Code() string
+
+	// Returns the error details message.
+	Message() string
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErrs() []error
+}
+
+// BatchedErrors is a batch of errors which also wraps lower level errors with
+// code, message, and original errors. Calling Error() will include all errors
+// that occurred in the batch.
+//
+// Replaces BatchError
+type BatchedErrors interface {
+	// Satisfy the base Error interface.
+	Error
+
+	// Returns the original error if one was set.  Nil is returned if not set.
+	OrigErrs() []error
+}
+
+// New returns an Error object described by the code, message, and origErr.
+//
+// If origErr satisfies the Error interface it will not be wrapped within a new
+// Error object and will instead be returned.
+func New(code, message string, origErr error) Error {
+	var errs []error
+	if origErr != nil {
+		errs = append(errs, origErr)
+	}
+	return newBaseError(code, message, errs)
+}
+
+// NewBatchError returns an BatchedErrors with a collection of errors as an
+// array of errors.
+func NewBatchError(code, message string, errs []error) BatchedErrors {
+	return newBaseError(code, message, errs)
+}
+
+// A RequestFailure is an interface to extract request failure information from
+// an Error such as the request ID of the failed request returned by a service.
+// RequestFailures may not always have a requestID value if the request failed
+// prior to reaching the service such as a connection error.
+//
+// Example:
+//
+//     output, err := s3manage.Upload(svc, input, opts)
+//     if err != nil {
+//         if reqerr, ok := err.(RequestFailure); ok {
+//             log.Println("Request failed", reqerr.Code(), reqerr.Message(), reqerr.RequestID())
+//         } else {
+//             log.Println("Error:", err.Error())
+//         }
+//     }
+//
+// Combined with awserr.Error:
+//
+//    output, err := s3manage.Upload(svc, input, opts)
+//    if err != nil {
+//        if awsErr, ok := err.(awserr.Error); ok {
+//            // Generic AWS Error with Code, Message, and original error (if any)
+//            fmt.Println(awsErr.Code(), awsErr.Message(), awsErr.OrigErr())
+//
+//            if reqErr, ok := err.(awserr.RequestFailure); ok {
+//                // A service error occurred
+//                fmt.Println(reqErr.StatusCode(), reqErr.RequestID())
+//            }
+//        } else {
+//            fmt.Println(err.Error())
+//        }
+//    }
+//
+type RequestFailure interface {
+	Error
+
+	// The status code of the HTTP response.
+	StatusCode() int
+
+	// The request ID returned by the service for a request failure. This will
+	// be empty if no request ID is available such as the request failed due
+	// to a connection error.
+	RequestID() string
+}
+
+// NewRequestFailure returns a new request error wrapper for the given Error
+// provided.
+func NewRequestFailure(err Error, statusCode int, reqID string) RequestFailure {
+	return newRequestError(err, statusCode, reqID)
+}
@@ -0,0 +1,194 @@
+package awserr
+
+import "fmt"
+
+// SprintError returns a string of the formatted error code.
+//
+// Both extra and origErr are optional.  If they are included their lines
+// will be added, but if they are not included their lines will be ignored.
+func SprintError(code, message, extra string, origErr error) string {
+	msg := fmt.Sprintf("%s: %s", code, message)
+	if extra != "" {
+		msg = fmt.Sprintf("%s\n\t%s", msg, extra)
+	}
+	if origErr != nil {
+		msg = fmt.Sprintf("%s\ncaused by: %s", msg, origErr.Error())
+	}
+	return msg
+}
+
+// A baseError wraps the code and message which defines an error. It also
+// can be used to wrap an original error object.
+//
+// Should be used as the root for errors satisfying the awserr.Error. Also
+// for any error which does not fit into a specific error wrapper type.
+type baseError struct {
+	// Classification of error
+	code string
+
+	// Detailed information about error
+	message string
+
+	// Optional original error this error is based off of. Allows building
+	// chained errors.
+	errs []error
+}
+
+// newBaseError returns an error object for the code, message, and errors.
+//
+// code is a short no whitespace phrase depicting the classification of
+// the error that is being created.
+//
+// message is the free flow string containing detailed information about the
+// error.
+//
+// origErrs is the error objects which will be nested under the new errors to
+// be returned.
+func newBaseError(code, message string, origErrs []error) *baseError {
+	b := &baseError{
+		code:    code,
+		message: message,
+		errs:    origErrs,
+	}
+
+	return b
+}
+
+// Error returns the string representation of the error.
+//
+// See ErrorWithExtra for formatting.
+//
+// Satisfies the error interface.
+func (b baseError) Error() string {
+	size := len(b.errs)
+	if size > 0 {
+		return SprintError(b.code, b.message, "", errorList(b.errs))
+	}
+
+	return SprintError(b.code, b.message, "", nil)
+}
+
+// String returns the string representation of the error.
+// Alias for Error to satisfy the stringer interface.
+func (b baseError) String() string {
+	return b.Error()
+}
+
+// Code returns the short phrase depicting the classification of the error.
+func (b baseError) Code() string {
+	return b.code
+}
+
+// Message returns the error details message.
+func (b baseError) Message() string {
+	return b.message
+}
+
+// OrigErr returns the original error if one was set. Nil is returned if no
+// error was set. This only returns the first element in the list. If the full
+// list is needed, use BatchedErrors.
+func (b baseError) OrigErr() error {
+	switch len(b.errs) {
+	case 0:
+		return nil
+	case 1:
+		return b.errs[0]
+	default:
+		if err, ok := b.errs[0].(Error); ok {
+			return NewBatchError(err.Code(), err.Message(), b.errs[1:])
+		}
+		return NewBatchError("BatchedErrors",
+			"multiple errors occurred", b.errs)
+	}
+}
+
+// OrigErrs returns the original errors if one was set. An empty slice is
+// returned if no error was set.
+func (b baseError) OrigErrs() []error {
+	return b.errs
+}
+
+// So that the Error interface type can be included as an anonymous field
+// in the requestError struct and not conflict with the error.Error() method.
+type awsError Error
+
+// A requestError wraps a request or service error.
+//
+// Composed of baseError for code, message, and original error.
+type requestError struct {
+	awsError
+	statusCode int
+	requestID  string
+}
+
+// newRequestError returns a wrapped error with additional information for
+// request status code, and service requestID.
+//
+// Should be used to wrap all request which involve service requests. Even if
+// the request failed without a service response, but had an HTTP status code
+// that may be meaningful.
+//
+// Also wraps original errors via the baseError.
+func newRequestError(err Error, statusCode int, requestID string) *requestError {
+	return &requestError{
+		awsError:   err,
+		statusCode: statusCode,
+		requestID:  requestID,
+	}
+}
+
+// Error returns the string representation of the error.
+// Satisfies the error interface.
+func (r requestError) Error() string {
+	extra := fmt.Sprintf("status code: %d, request id: %s",
+		r.statusCode, r.requestID)
+	return SprintError(r.Code(), r.Message(), extra, r.OrigErr())
+}
+
+// String returns the string representation of the error.
+// Alias for Error to satisfy the stringer interface.
+func (r requestError) String() string {
+	return r.Error()
+}
+
+// StatusCode returns the wrapped status code for the error
+func (r requestError) StatusCode() int {
+	return r.statusCode
+}
+
+// RequestID returns the wrapped requestID
+func (r requestError) RequestID() string {
+	return r.requestID
+}
+
+// OrigErrs returns the original errors if one was set. An empty slice is
+// returned if no error was set.
+func (r requestError) OrigErrs() []error {
+	if b, ok := r.awsError.(BatchedErrors); ok {
+		return b.OrigErrs()
+	}
+	return []error{r.OrigErr()}
+}
+
+// An error list that satisfies the golang interface
+type errorList []error
+
+// Error returns the string representation of the error.
+//
+// Satisfies the error interface.
+func (e errorList) Error() string {
+	msg := ""
+	// How do we want to handle the array size being zero
+	if size := len(e); size > 0 {
+		for i := 0; i < size; i++ {
+			msg += fmt.Sprintf("%s", e[i].Error())
+			// We check the next index to see if it is within the slice.
+			// If it is, then we append a newline. We do this, because unit tests
+			// could be broken with the additional '\n'
+			if i+1 < size {
+				msg += "\n"
+			}
+		}
+	}
+	return msg
+}
@@ -0,0 +1,108 @@
+package awsutil
+
+import (
+	"io"
+	"reflect"
+	"time"
+)
+
+// Copy deeply copies a src structure to dst. Useful for copying request and
+// response structures.
+//
+// Can copy between structs of different type, but will only copy fields which
+// are assignable, and exist in both structs. Fields which are not assignable,
+// or do not exist in both structs are ignored.
+func Copy(dst, src interface{}) {
+	dstval := reflect.ValueOf(dst)
+	if !dstval.IsValid() {
+		panic("Copy dst cannot be nil")
+	}
+
+	rcopy(dstval, reflect.ValueOf(src), true)
+}
+
+// CopyOf returns a copy of src while also allocating the memory for dst.
+// src must be a pointer type or this operation will fail.
+func CopyOf(src interface{}) (dst interface{}) {
+	dsti := reflect.New(reflect.TypeOf(src).Elem())
+	dst = dsti.Interface()
+	rcopy(dsti, reflect.ValueOf(src), true)
+	return
+}
+
+// rcopy performs a recursive copy of values from the source to destination.
+//
+// root is used to skip certain aspects of the copy which are not valid
+// for the root node of a object.
+func rcopy(dst, src reflect.Value, root bool) {
+	if !src.IsValid() {
+		return
+	}
+
+	switch src.Kind() {
+	case reflect.Ptr:
+		if _, ok := src.Interface().(io.Reader); ok {
+			if dst.Kind() == reflect.Ptr && dst.Elem().CanSet() {
+				dst.Elem().Set(src)
+			} else if dst.CanSet() {
+				dst.Set(src)
+			}
+		} else {
+			e := src.Type().Elem()
+			if dst.CanSet() && !src.IsNil() {
+				if _, ok := src.Interface().(*time.Time); !ok {
+					dst.Set(reflect.New(e))
+				} else {
+					tempValue := reflect.New(e)
+					tempValue.Elem().Set(src.Elem())
+					// Sets time.Time's unexported values
+					dst.Set(tempValue)
+				}
+			}
+			if src.Elem().IsValid() {
+				// Keep the current root state since the depth hasn't changed
+				rcopy(dst.Elem(), src.Elem(), root)
+			}
+		}
+	case reflect.Struct:
+		t := dst.Type()
+		for i := 0; i < t.NumField(); i++ {
+			name := t.Field(i).Name
+			srcVal := src.FieldByName(name)
+			dstVal := dst.FieldByName(name)
+			if srcVal.IsValid() && dstVal.CanSet() {
+				rcopy(dstVal, srcVal, false)
+			}
+		}
+	case reflect.Slice:
+		if src.IsNil() {
+			break
+		}
+
+		s := reflect.MakeSlice(src.Type(), src.Len(), src.Cap())
+		dst.Set(s)
+		for i := 0; i < src.Len(); i++ {
+			rcopy(dst.Index(i), src.Index(i), false)
+		}
+	case reflect.Map:
+		if src.IsNil() {
+			break
+		}
+
+		s := reflect.MakeMap(src.Type())
+		dst.Set(s)
+		for _, k := range src.MapKeys() {
+			v := src.MapIndex(k)
+			v2 := reflect.New(v.Type()).Elem()
+			rcopy(v2, v, false)
+			dst.SetMapIndex(k, v2)
+		}
+	default:
+		// Assign the value if possible. If its not assignable, the value would
+		// need to be converted and the impact of that may be unexpected, or is
+		// not compatible with the dst type.
+		if src.Type().AssignableTo(dst.Type()) {
+			dst.Set(src)
+		}
+	}
+}
@@ -0,0 +1,27 @@
+package awsutil
+
+import (
+	"reflect"
+)
+
+// DeepEqual returns if the two values are deeply equal like reflect.DeepEqual.
+// In addition to this, this method will also dereference the input values if
+// possible so the DeepEqual performed will not fail if one parameter is a
+// pointer and the other is not.
+//
+// DeepEqual will not perform indirection of nested values of the input parameters.
+func DeepEqual(a, b interface{}) bool {
+	ra := reflect.Indirect(reflect.ValueOf(a))
+	rb := reflect.Indirect(reflect.ValueOf(b))
+
+	if raValid, rbValid := ra.IsValid(), rb.IsValid(); !raValid && !rbValid {
+		// If the elements are both nil, and of the same type the are equal
+		// If they are of different types they are not equal
+		return reflect.TypeOf(a) == reflect.TypeOf(b)
+	} else if raValid != rbValid {
+		// Both values must be valid to be equal
+		return false
+	}
+
+	return reflect.DeepEqual(ra.Interface(), rb.Interface())
+}
@@ -0,0 +1,222 @@
+package awsutil
+
+import (
+	"reflect"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/jmespath/go-jmespath"
+)
+
+var indexRe = regexp.MustCompile(`(.+)\[(-?\d+)?\]$`)
+
+// rValuesAtPath returns a slice of values found in value v. The values
+// in v are explored recursively so all nested values are collected.
+func rValuesAtPath(v interface{}, path string, createPath, caseSensitive, nilTerm bool) []reflect.Value {
+	pathparts := strings.Split(path, "||")
+	if len(pathparts) > 1 {
+		for _, pathpart := range pathparts {
+			vals := rValuesAtPath(v, pathpart, createPath, caseSensitive, nilTerm)
+			if len(vals) > 0 {
+				return vals
+			}
+		}
+		return nil
+	}
+
+	values := []reflect.Value{reflect.Indirect(reflect.ValueOf(v))}
+	components := strings.Split(path, ".")
+	for len(values) > 0 && len(components) > 0 {
+		var index *int64
+		var indexStar bool
+		c := strings.TrimSpace(components[0])
+		if c == "" { // no actual component, illegal syntax
+			return nil
+		} else if caseSensitive && c != "*" && strings.ToLower(c[0:1]) == c[0:1] {
+			// TODO normalize case for user
+			return nil // don't support unexported fields
+		}
+
+		// parse this component
+		if m := indexRe.FindStringSubmatch(c); m != nil {
+			c = m[1]
+			if m[2] == "" {
+				index = nil
+				indexStar = true
+			} else {
+				i, _ := strconv.ParseInt(m[2], 10, 32)
+				index = &i
+				indexStar = false
+			}
+		}
+
+		nextvals := []reflect.Value{}
+		for _, value := range values {
+			// pull component name out of struct member
+			if value.Kind() != reflect.Struct {
+				continue
+			}
+
+			if c == "*" { // pull all members
+				for i := 0; i < value.NumField(); i++ {
+					if f := reflect.Indirect(value.Field(i)); f.IsValid() {
+						nextvals = append(nextvals, f)
+					}
+				}
+				continue
+			}
+
+			value = value.FieldByNameFunc(func(name string) bool {
+				if c == name {
+					return true
+				} else if !caseSensitive && strings.ToLower(name) == strings.ToLower(c) {
+					return true
+				}
+				return false
+			})
+
+			if nilTerm && value.Kind() == reflect.Ptr && len(components[1:]) == 0 {
+				if !value.IsNil() {
+					value.Set(reflect.Zero(value.Type()))
+				}
+				return []reflect.Value{value}
+			}
+
+			if createPath && value.Kind() == reflect.Ptr && value.IsNil() {
+				// TODO if the value is the terminus it should not be created
+				// if the value to be set to its position is nil.
+				value.Set(reflect.New(value.Type().Elem()))
+				value = value.Elem()
+			} else {
+				value = reflect.Indirect(value)
+			}
+
+			if value.Kind() == reflect.Slice || value.Kind() == reflect.Map {
+				if !createPath && value.IsNil() {
+					value = reflect.ValueOf(nil)
+				}
+			}
+
+			if value.IsValid() {
+				nextvals = append(nextvals, value)
+			}
+		}
+		values = nextvals
+
+		if indexStar || index != nil {
+			nextvals = []reflect.Value{}
+			for _, valItem := range values {
+				value := reflect.Indirect(valItem)
+				if value.Kind() != reflect.Slice {
+					continue
+				}
+
+				if indexStar { // grab all indices
+					for i := 0; i < value.Len(); i++ {
+						idx := reflect.Indirect(value.Index(i))
+						if idx.IsValid() {
+							nextvals = append(nextvals, idx)
+						}
+					}
+					continue
+				}
+
+				// pull out index
+				i := int(*index)
+				if i >= value.Len() { // check out of bounds
+					if createPath {
+						// TODO resize slice
+					} else {
+						continue
+					}
+				} else if i < 0 { // support negative indexing
+					i = value.Len() + i
+				}
+				value = reflect.Indirect(value.Index(i))
+
+				if value.Kind() == reflect.Slice || value.Kind() == reflect.Map {
+					if !createPath && value.IsNil() {
+						value = reflect.ValueOf(nil)
+					}
+				}
+
+				if value.IsValid() {
+					nextvals = append(nextvals, value)
+				}
+			}
+			values = nextvals
+		}
+
+		components = components[1:]
+	}
+	return values
+}
+
+// ValuesAtPath returns a list of values at the case insensitive lexical
+// path inside of a structure.
+func ValuesAtPath(i interface{}, path string) ([]interface{}, error) {
+	result, err := jmespath.Search(path, i)
+	if err != nil {
+		return nil, err
+	}
+
+	v := reflect.ValueOf(result)
+	if !v.IsValid() || (v.Kind() == reflect.Ptr && v.IsNil()) {
+		return nil, nil
+	}
+	if s, ok := result.([]interface{}); ok {
+		return s, err
+	}
+	if v.Kind() == reflect.Map && v.Len() == 0 {
+		return nil, nil
+	}
+	if v.Kind() == reflect.Slice {
+		out := make([]interface{}, v.Len())
+		for i := 0; i < v.Len(); i++ {
+			out[i] = v.Index(i).Interface()
+		}
+		return out, nil
+	}
+
+	return []interface{}{result}, nil
+}
+
+// SetValueAtPath sets a value at the case insensitive lexical path inside
+// of a structure.
+func SetValueAtPath(i interface{}, path string, v interface{}) {
+	if rvals := rValuesAtPath(i, path, true, false, v == nil); rvals != nil {
+		for _, rval := range rvals {
+			if rval.Kind() == reflect.Ptr && rval.IsNil() {
+				continue
+			}
+			setValue(rval, v)
+		}
+	}
+}
+
+func setValue(dstVal reflect.Value, src interface{}) {
+	if dstVal.Kind() == reflect.Ptr {
+		dstVal = reflect.Indirect(dstVal)
+	}
+	srcVal := reflect.ValueOf(src)
+
+	if !srcVal.IsValid() { // src is literal nil
+		if dstVal.CanAddr() {
+			// Convert to pointer so that pointer's value can be nil'ed
+			//                     dstVal = dstVal.Addr()
+		}
+		dstVal.Set(reflect.Zero(dstVal.Type()))
+
+	} else if srcVal.Kind() == reflect.Ptr {
+		if srcVal.IsNil() {
+			srcVal = reflect.Zero(dstVal.Type())
+		} else {
+			srcVal = reflect.ValueOf(src).Elem()
+		}
+		dstVal.Set(srcVal)
+	} else {
+		dstVal.Set(srcVal)
+	}
+
+}
@@ -0,0 +1,113 @@
+package awsutil
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+)
+
+// Prettify returns the string representation of a value.
+func Prettify(i interface{}) string {
+	var buf bytes.Buffer
+	prettify(reflect.ValueOf(i), 0, &buf)
+	return buf.String()
+}
+
+// prettify will recursively walk value v to build a textual
+// representation of the value.
+func prettify(v reflect.Value, indent int, buf *bytes.Buffer) {
+	for v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	switch v.Kind() {
+	case reflect.Struct:
+		strtype := v.Type().String()
+		if strtype == "time.Time" {
+			fmt.Fprintf(buf, "%s", v.Interface())
+			break
+		} else if strings.HasPrefix(strtype, "io.") {
+			buf.WriteString("<buffer>")
+			break
+		}
+
+		buf.WriteString("{\n")
+
+		names := []string{}
+		for i := 0; i < v.Type().NumField(); i++ {
+			name := v.Type().Field(i).Name
+			f := v.Field(i)
+			if name[0:1] == strings.ToLower(name[0:1]) {
+				continue // ignore unexported fields
+			}
+			if (f.Kind() == reflect.Ptr || f.Kind() == reflect.Slice || f.Kind() == reflect.Map) && f.IsNil() {
+				continue // ignore unset fields
+			}
+			names = append(names, name)
+		}
+
+		for i, n := range names {
+			val := v.FieldByName(n)
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(n + ": ")
+			prettify(val, indent+2, buf)
+
+			if i < len(names)-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	case reflect.Slice:
+		strtype := v.Type().String()
+		if strtype == "[]uint8" {
+			fmt.Fprintf(buf, "<binary> len %d", v.Len())
+			break
+		}
+
+		nl, id, id2 := "", "", ""
+		if v.Len() > 3 {
+			nl, id, id2 = "\n", strings.Repeat(" ", indent), strings.Repeat(" ", indent+2)
+		}
+		buf.WriteString("[" + nl)
+		for i := 0; i < v.Len(); i++ {
+			buf.WriteString(id2)
+			prettify(v.Index(i), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString("," + nl)
+			}
+		}
+
+		buf.WriteString(nl + id + "]")
+	case reflect.Map:
+		buf.WriteString("{\n")
+
+		for i, k := range v.MapKeys() {
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(k.String() + ": ")
+			prettify(v.MapIndex(k), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	default:
+		if !v.IsValid() {
+			fmt.Fprint(buf, "<invalid value>")
+			return
+		}
+		format := "%v"
+		switch v.Interface().(type) {
+		case string:
+			format = "%q"
+		case io.ReadSeeker, io.Reader:
+			format = "buffer(%p)"
+		}
+		fmt.Fprintf(buf, format, v.Interface())
+	}
+}
@@ -0,0 +1,89 @@
+package awsutil
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// StringValue returns the string representation of a value.
+func StringValue(i interface{}) string {
+	var buf bytes.Buffer
+	stringValue(reflect.ValueOf(i), 0, &buf)
+	return buf.String()
+}
+
+func stringValue(v reflect.Value, indent int, buf *bytes.Buffer) {
+	for v.Kind() == reflect.Ptr {
+		v = v.Elem()
+	}
+
+	switch v.Kind() {
+	case reflect.Struct:
+		buf.WriteString("{\n")
+
+		names := []string{}
+		for i := 0; i < v.Type().NumField(); i++ {
+			name := v.Type().Field(i).Name
+			f := v.Field(i)
+			if name[0:1] == strings.ToLower(name[0:1]) {
+				continue // ignore unexported fields
+			}
+			if (f.Kind() == reflect.Ptr || f.Kind() == reflect.Slice) && f.IsNil() {
+				continue // ignore unset fields
+			}
+			names = append(names, name)
+		}
+
+		for i, n := range names {
+			val := v.FieldByName(n)
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(n + ": ")
+			stringValue(val, indent+2, buf)
+
+			if i < len(names)-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	case reflect.Slice:
+		nl, id, id2 := "", "", ""
+		if v.Len() > 3 {
+			nl, id, id2 = "\n", strings.Repeat(" ", indent), strings.Repeat(" ", indent+2)
+		}
+		buf.WriteString("[" + nl)
+		for i := 0; i < v.Len(); i++ {
+			buf.WriteString(id2)
+			stringValue(v.Index(i), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString("," + nl)
+			}
+		}
+
+		buf.WriteString(nl + id + "]")
+	case reflect.Map:
+		buf.WriteString("{\n")
+
+		for i, k := range v.MapKeys() {
+			buf.WriteString(strings.Repeat(" ", indent+2))
+			buf.WriteString(k.String() + ": ")
+			stringValue(v.MapIndex(k), indent+2, buf)
+
+			if i < v.Len()-1 {
+				buf.WriteString(",\n")
+			}
+		}
+
+		buf.WriteString("\n" + strings.Repeat(" ", indent) + "}")
+	default:
+		format := "%v"
+		switch v.Interface().(type) {
+		case string:
+			format = "%q"
+		}
+		fmt.Fprintf(buf, format, v.Interface())
+	}
+}
@@ -0,0 +1,96 @@
+package client
+
+import (
+	"fmt"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/client/metadata"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// A Config provides configuration to a service client instance.
+type Config struct {
+	Config        *aws.Config
+	Handlers      request.Handlers
+	Endpoint      string
+	SigningRegion string
+	SigningName   string
+
+	// States that the signing name did not come from a modeled source but
+	// was derived based on other data. Used by service client constructors
+	// to determine if the signin name can be overriden based on metadata the
+	// service has.
+	SigningNameDerived bool
+}
+
+// ConfigProvider provides a generic way for a service client to receive
+// the ClientConfig without circular dependencies.
+type ConfigProvider interface {
+	ClientConfig(serviceName string, cfgs ...*aws.Config) Config
+}
+
+// ConfigNoResolveEndpointProvider same as ConfigProvider except it will not
+// resolve the endpoint automatically. The service client's endpoint must be
+// provided via the aws.Config.Endpoint field.
+type ConfigNoResolveEndpointProvider interface {
+	ClientConfigNoResolveEndpoint(cfgs ...*aws.Config) Config
+}
+
+// A Client implements the base client request and response handling
+// used by all service clients.
+type Client struct {
+	request.Retryer
+	metadata.ClientInfo
+
+	Config   aws.Config
+	Handlers request.Handlers
+}
+
+// New will return a pointer to a new initialized service client.
+func New(cfg aws.Config, info metadata.ClientInfo, handlers request.Handlers, options ...func(*Client)) *Client {
+	svc := &Client{
+		Config:     cfg,
+		ClientInfo: info,
+		Handlers:   handlers.Copy(),
+	}
+
+	switch retryer, ok := cfg.Retryer.(request.Retryer); {
+	case ok:
+		svc.Retryer = retryer
+	case cfg.Retryer != nil && cfg.Logger != nil:
+		s := fmt.Sprintf("WARNING: %T does not implement request.Retryer; using DefaultRetryer instead", cfg.Retryer)
+		cfg.Logger.Log(s)
+		fallthrough
+	default:
+		maxRetries := aws.IntValue(cfg.MaxRetries)
+		if cfg.MaxRetries == nil || maxRetries == aws.UseServiceDefaultRetries {
+			maxRetries = 3
+		}
+		svc.Retryer = DefaultRetryer{NumMaxRetries: maxRetries}
+	}
+
+	svc.AddDebugHandlers()
+
+	for _, option := range options {
+		option(svc)
+	}
+
+	return svc
+}
+
+// NewRequest returns a new Request pointer for the service API
+// operation and parameters.
+func (c *Client) NewRequest(operation *request.Operation, params interface{}, data interface{}) *request.Request {
+	return request.New(c.Config, c.ClientInfo, c.Handlers, c.Retryer, operation, params, data)
+}
+
+// AddDebugHandlers injects debug logging handlers into the service to log request
+// debug information.
+func (c *Client) AddDebugHandlers() {
+	if !c.Config.LogLevel.AtLeast(aws.LogDebug) {
+		return
+	}
+
+	c.Handlers.Send.PushFrontNamed(request.NamedHandler{Name: "awssdk.client.LogRequest", Fn: logRequest})
+	c.Handlers.Send.PushBackNamed(request.NamedHandler{Name: "awssdk.client.LogResponse", Fn: logResponse})
+}
@@ -0,0 +1,116 @@
+package client
+
+import (
+	"strconv"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws/request"
+	"github.com/aws/aws-sdk-go/internal/sdkrand"
+)
+
+// DefaultRetryer implements basic retry logic using exponential backoff for
+// most services. If you want to implement custom retry logic, implement the
+// request.Retryer interface or create a structure type that composes this
+// struct and override the specific methods. For example, to override only
+// the MaxRetries method:
+//
+//		type retryer struct {
+//      client.DefaultRetryer
+//    }
+//
+//    // This implementation always has 100 max retries
+//    func (d retryer) MaxRetries() int { return 100 }
+type DefaultRetryer struct {
+	NumMaxRetries int
+}
+
+// MaxRetries returns the number of maximum returns the service will use to make
+// an individual API request.
+func (d DefaultRetryer) MaxRetries() int {
+	return d.NumMaxRetries
+}
+
+// RetryRules returns the delay duration before retrying this request again
+func (d DefaultRetryer) RetryRules(r *request.Request) time.Duration {
+	// Set the upper limit of delay in retrying at ~five minutes
+	minTime := 30
+	throttle := d.shouldThrottle(r)
+	if throttle {
+		if delay, ok := getRetryDelay(r); ok {
+			return delay
+		}
+
+		minTime = 500
+	}
+
+	retryCount := r.RetryCount
+	if throttle && retryCount > 8 {
+		retryCount = 8
+	} else if retryCount > 13 {
+		retryCount = 13
+	}
+
+	delay := (1 << uint(retryCount)) * (sdkrand.SeededRand.Intn(minTime) + minTime)
+	return time.Duration(delay) * time.Millisecond
+}
+
+// ShouldRetry returns true if the request should be retried.
+func (d DefaultRetryer) ShouldRetry(r *request.Request) bool {
+	// If one of the other handlers already set the retry state
+	// we don't want to override it based on the service's state
+	if r.Retryable != nil {
+		return *r.Retryable
+	}
+
+	if r.HTTPResponse.StatusCode >= 500 && r.HTTPResponse.StatusCode != 501 {
+		return true
+	}
+	return r.IsErrorRetryable() || d.shouldThrottle(r)
+}
+
+// ShouldThrottle returns true if the request should be throttled.
+func (d DefaultRetryer) shouldThrottle(r *request.Request) bool {
+	switch r.HTTPResponse.StatusCode {
+	case 429:
+	case 502:
+	case 503:
+	case 504:
+	default:
+		return r.IsErrorThrottle()
+	}
+
+	return true
+}
+
+// This will look in the Retry-After header, RFC 7231, for how long
+// it will wait before attempting another request
+func getRetryDelay(r *request.Request) (time.Duration, bool) {
+	if !canUseRetryAfterHeader(r) {
+		return 0, false
+	}
+
+	delayStr := r.HTTPResponse.Header.Get("Retry-After")
+	if len(delayStr) == 0 {
+		return 0, false
+	}
+
+	delay, err := strconv.Atoi(delayStr)
+	if err != nil {
+		return 0, false
+	}
+
+	return time.Duration(delay) * time.Second, true
+}
+
+// Will look at the status code to see if the retry header pertains to
+// the status code.
+func canUseRetryAfterHeader(r *request.Request) bool {
+	switch r.HTTPResponse.StatusCode {
+	case 429:
+	case 503:
+	default:
+		return false
+	}
+
+	return true
+}
@@ -0,0 +1,112 @@
+package client
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http/httputil"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+const logReqMsg = `DEBUG: Request %s/%s Details:
+---[ REQUEST POST-SIGN ]-----------------------------
+%s
+-----------------------------------------------------`
+
+const logReqErrMsg = `DEBUG ERROR: Request %s/%s:
+---[ REQUEST DUMP ERROR ]-----------------------------
+%s
+------------------------------------------------------`
+
+type logWriter struct {
+	// Logger is what we will use to log the payload of a response.
+	Logger aws.Logger
+	// buf stores the contents of what has been read
+	buf *bytes.Buffer
+}
+
+func (logger *logWriter) Write(b []byte) (int, error) {
+	return logger.buf.Write(b)
+}
+
+type teeReaderCloser struct {
+	// io.Reader will be a tee reader that is used during logging.
+	// This structure will read from a body and write the contents to a logger.
+	io.Reader
+	// Source is used just to close when we are done reading.
+	Source io.ReadCloser
+}
+
+func (reader *teeReaderCloser) Close() error {
+	return reader.Source.Close()
+}
+
+func logRequest(r *request.Request) {
+	logBody := r.Config.LogLevel.Matches(aws.LogDebugWithHTTPBody)
+	bodySeekable := aws.IsReaderSeekable(r.Body)
+	dumpedBody, err := httputil.DumpRequestOut(r.HTTPRequest, logBody)
+	if err != nil {
+		r.Config.Logger.Log(fmt.Sprintf(logReqErrMsg, r.ClientInfo.ServiceName, r.Operation.Name, err))
+		return
+	}
+
+	if logBody {
+		if !bodySeekable {
+			r.SetReaderBody(aws.ReadSeekCloser(r.HTTPRequest.Body))
+		}
+		// Reset the request body because dumpRequest will re-wrap the r.HTTPRequest's
+		// Body as a NoOpCloser and will not be reset after read by the HTTP
+		// client reader.
+		r.ResetBody()
+	}
+
+	r.Config.Logger.Log(fmt.Sprintf(logReqMsg, r.ClientInfo.ServiceName, r.Operation.Name, string(dumpedBody)))
+}
+
+const logRespMsg = `DEBUG: Response %s/%s Details:
+---[ RESPONSE ]--------------------------------------
+%s
+-----------------------------------------------------`
+
+const logRespErrMsg = `DEBUG ERROR: Response %s/%s:
+---[ RESPONSE DUMP ERROR ]-----------------------------
+%s
+-----------------------------------------------------`
+
+func logResponse(r *request.Request) {
+	lw := &logWriter{r.Config.Logger, bytes.NewBuffer(nil)}
+	r.HTTPResponse.Body = &teeReaderCloser{
+		Reader: io.TeeReader(r.HTTPResponse.Body, lw),
+		Source: r.HTTPResponse.Body,
+	}
+
+	handlerFn := func(req *request.Request) {
+		body, err := httputil.DumpResponse(req.HTTPResponse, false)
+		if err != nil {
+			lw.Logger.Log(fmt.Sprintf(logRespErrMsg, req.ClientInfo.ServiceName, req.Operation.Name, err))
+			return
+		}
+
+		b, err := ioutil.ReadAll(lw.buf)
+		if err != nil {
+			lw.Logger.Log(fmt.Sprintf(logRespErrMsg, req.ClientInfo.ServiceName, req.Operation.Name, err))
+			return
+		}
+		lw.Logger.Log(fmt.Sprintf(logRespMsg, req.ClientInfo.ServiceName, req.Operation.Name, string(body)))
+		if req.Config.LogLevel.Matches(aws.LogDebugWithHTTPBody) {
+			lw.Logger.Log(string(b))
+		}
+	}
+
+	const handlerName = "awsdk.client.LogResponse.ResponseBody"
+
+	r.Handlers.Unmarshal.SetBackNamed(request.NamedHandler{
+		Name: handlerName, Fn: handlerFn,
+	})
+	r.Handlers.UnmarshalError.SetBackNamed(request.NamedHandler{
+		Name: handlerName, Fn: handlerFn,
+	})
+}
@@ -0,0 +1,12 @@
+package metadata
+
+// ClientInfo wraps immutable data from the client.Client structure.
+type ClientInfo struct {
+	ServiceName   string
+	APIVersion    string
+	Endpoint      string
+	SigningName   string
+	SigningRegion string
+	JSONVersion   string
+	TargetPrefix  string
+}
@@ -0,0 +1,492 @@
+package aws
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/endpoints"
+)
+
+// UseServiceDefaultRetries instructs the config to use the service's own
+// default number of retries. This will be the default action if
+// Config.MaxRetries is nil also.
+const UseServiceDefaultRetries = -1
+
+// RequestRetryer is an alias for a type that implements the request.Retryer
+// interface.
+type RequestRetryer interface{}
+
+// A Config provides service configuration for service clients. By default,
+// all clients will use the defaults.DefaultConfig tructure.
+//
+//     // Create Session with MaxRetry configuration to be shared by multiple
+//     // service clients.
+//     sess := session.Must(session.NewSession(&aws.Config{
+//         MaxRetries: aws.Int(3),
+//     }))
+//
+//     // Create S3 service client with a specific Region.
+//     svc := s3.New(sess, &aws.Config{
+//         Region: aws.String("us-west-2"),
+//     })
+type Config struct {
+	// Enables verbose error printing of all credential chain errors.
+	// Should be used when wanting to see all errors while attempting to
+	// retrieve credentials.
+	CredentialsChainVerboseErrors *bool
+
+	// The credentials object to use when signing requests. Defaults to a
+	// chain of credential providers to search for credentials in environment
+	// variables, shared credential file, and EC2 Instance Roles.
+	Credentials *credentials.Credentials
+
+	// An optional endpoint URL (hostname only or fully qualified URI)
+	// that overrides the default generated endpoint for a client. Set this
+	// to `""` to use the default generated endpoint.
+	//
+	// @note You must still provide a `Region` value when specifying an
+	//   endpoint for a client.
+	Endpoint *string
+
+	// The resolver to use for looking up endpoints for AWS service clients
+	// to use based on region.
+	EndpointResolver endpoints.Resolver
+
+	// EnforceShouldRetryCheck is used in the AfterRetryHandler to always call
+	// ShouldRetry regardless of whether or not if request.Retryable is set.
+	// This will utilize ShouldRetry method of custom retryers. If EnforceShouldRetryCheck
+	// is not set, then ShouldRetry will only be called if request.Retryable is nil.
+	// Proper handling of the request.Retryable field is important when setting this field.
+	EnforceShouldRetryCheck *bool
+
+	// The region to send requests to. This parameter is required and must
+	// be configured globally or on a per-client basis unless otherwise
+	// noted. A full list of regions is found in the "Regions and Endpoints"
+	// document.
+	//
+	// @see http://docs.aws.amazon.com/general/latest/gr/rande.html
+	//   AWS Regions and Endpoints
+	Region *string
+
+	// Set this to `true` to disable SSL when sending requests. Defaults
+	// to `false`.
+	DisableSSL *bool
+
+	// The HTTP client to use when sending requests. Defaults to
+	// `http.DefaultClient`.
+	HTTPClient *http.Client
+
+	// An integer value representing the logging level. The default log level
+	// is zero (LogOff), which represents no logging. To enable logging set
+	// to a LogLevel Value.
+	LogLevel *LogLevelType
+
+	// The logger writer interface to write logging messages to. Defaults to
+	// standard out.
+	Logger Logger
+
+	// The maximum number of times that a request will be retried for failures.
+	// Defaults to -1, which defers the max retry setting to the service
+	// specific configuration.
+	MaxRetries *int
+
+	// Retryer guides how HTTP requests should be retried in case of
+	// recoverable failures.
+	//
+	// When nil or the value does not implement the request.Retryer interface,
+	// the client.DefaultRetryer will be used.
+	//
+	// When both Retryer and MaxRetries are non-nil, the former is used and
+	// the latter ignored.
+	//
+	// To set the Retryer field in a type-safe manner and with chaining, use
+	// the request.WithRetryer helper function:
+	//
+	//   cfg := request.WithRetryer(aws.NewConfig(), myRetryer)
+	//
+	Retryer RequestRetryer
+
+	// Disables semantic parameter validation, which validates input for
+	// missing required fields and/or other semantic request input errors.
+	DisableParamValidation *bool
+
+	// Disables the computation of request and response checksums, e.g.,
+	// CRC32 checksums in Amazon DynamoDB.
+	DisableComputeChecksums *bool
+
+	// Set this to `true` to force the request to use path-style addressing,
+	// i.e., `http://s3.amazonaws.com/BUCKET/KEY`. By default, the S3 client
+	// will use virtual hosted bucket addressing when possible
+	// (`http://BUCKET.s3.amazonaws.com/KEY`).
+	//
+	// @note This configuration option is specific to the Amazon S3 service.
+	// @see http://docs.aws.amazon.com/AmazonS3/latest/dev/VirtualHosting.html
+	//   Amazon S3: Virtual Hosting of Buckets
+	S3ForcePathStyle *bool
+
+	// Set this to `true` to disable the SDK adding the `Expect: 100-Continue`
+	// header to PUT requests over 2MB of content. 100-Continue instructs the
+	// HTTP client not to send the body until the service responds with a
+	// `continue` status. This is useful to prevent sending the request body
+	// until after the request is authenticated, and validated.
+	//
+	// http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html
+	//
+	// 100-Continue is only enabled for Go 1.6 and above. See `http.Transport`'s
+	// `ExpectContinueTimeout` for information on adjusting the continue wait
+	// timeout. https://golang.org/pkg/net/http/#Transport
+	//
+	// You should use this flag to disble 100-Continue if you experience issues
+	// with proxies or third party S3 compatible services.
+	S3Disable100Continue *bool
+
+	// Set this to `true` to enable S3 Accelerate feature. For all operations
+	// compatible with S3 Accelerate will use the accelerate endpoint for
+	// requests. Requests not compatible will fall back to normal S3 requests.
+	//
+	// The bucket must be enable for accelerate to be used with S3 client with
+	// accelerate enabled. If the bucket is not enabled for accelerate an error
+	// will be returned. The bucket name must be DNS compatible to also work
+	// with accelerate.
+	S3UseAccelerate *bool
+
+	// S3DisableContentMD5Validation config option is temporarily disabled,
+	// For S3 GetObject API calls, #1837.
+	//
+	// Set this to `true` to disable the S3 service client from automatically
+	// adding the ContentMD5 to S3 Object Put and Upload API calls. This option
+	// will also disable the SDK from performing object ContentMD5 validation
+	// on GetObject API calls.
+	S3DisableContentMD5Validation *bool
+
+	// Set this to `true` to disable the EC2Metadata client from overriding the
+	// default http.Client's Timeout. This is helpful if you do not want the
+	// EC2Metadata client to create a new http.Client. This options is only
+	// meaningful if you're not already using a custom HTTP client with the
+	// SDK. Enabled by default.
+	//
+	// Must be set and provided to the session.NewSession() in order to disable
+	// the EC2Metadata overriding the timeout for default credentials chain.
+	//
+	// Example:
+	//    sess := session.Must(session.NewSession(aws.NewConfig()
+	//       .WithEC2MetadataDiableTimeoutOverride(true)))
+	//
+	//    svc := s3.New(sess)
+	//
+	EC2MetadataDisableTimeoutOverride *bool
+
+	// Instructs the endpoint to be generated for a service client to
+	// be the dual stack endpoint. The dual stack endpoint will support
+	// both IPv4 and IPv6 addressing.
+	//
+	// Setting this for a service which does not support dual stack will fail
+	// to make requets. It is not recommended to set this value on the session
+	// as it will apply to all service clients created with the session. Even
+	// services which don't support dual stack endpoints.
+	//
+	// If the Endpoint config value is also provided the UseDualStack flag
+	// will be ignored.
+	//
+	// Only supported with.
+	//
+	//     sess := session.Must(session.NewSession())
+	//
+	//     svc := s3.New(sess, &aws.Config{
+	//         UseDualStack: aws.Bool(true),
+	//     })
+	UseDualStack *bool
+
+	// SleepDelay is an override for the func the SDK will call when sleeping
+	// during the lifecycle of a request. Specifically this will be used for
+	// request delays. This value should only be used for testing. To adjust
+	// the delay of a request see the aws/client.DefaultRetryer and
+	// aws/request.Retryer.
+	//
+	// SleepDelay will prevent any Context from being used for canceling retry
+	// delay of an API operation. It is recommended to not use SleepDelay at all
+	// and specify a Retryer instead.
+	SleepDelay func(time.Duration)
+
+	// DisableRestProtocolURICleaning will not clean the URL path when making rest protocol requests.
+	// Will default to false. This would only be used for empty directory names in s3 requests.
+	//
+	// Example:
+	//    sess := session.Must(session.NewSession(&aws.Config{
+	//         DisableRestProtocolURICleaning: aws.Bool(true),
+	//    }))
+	//
+	//    svc := s3.New(sess)
+	//    out, err := svc.GetObject(&s3.GetObjectInput {
+	//    	Bucket: aws.String("bucketname"),
+	//    	Key: aws.String("//foo//bar//moo"),
+	//    })
+	DisableRestProtocolURICleaning *bool
+}
+
+// NewConfig returns a new Config pointer that can be chained with builder
+// methods to set multiple configuration values inline without using pointers.
+//
+//     // Create Session with MaxRetry configuration to be shared by multiple
+//     // service clients.
+//     sess := session.Must(session.NewSession(aws.NewConfig().
+//         WithMaxRetries(3),
+//     ))
+//
+//     // Create S3 service client with a specific Region.
+//     svc := s3.New(sess, aws.NewConfig().
+//         WithRegion("us-west-2"),
+//     )
+func NewConfig() *Config {
+	return &Config{}
+}
+
+// WithCredentialsChainVerboseErrors sets a config verbose errors boolean and returning
+// a Config pointer.
+func (c *Config) WithCredentialsChainVerboseErrors(verboseErrs bool) *Config {
+	c.CredentialsChainVerboseErrors = &verboseErrs
+	return c
+}
+
+// WithCredentials sets a config Credentials value returning a Config pointer
+// for chaining.
+func (c *Config) WithCredentials(creds *credentials.Credentials) *Config {
+	c.Credentials = creds
+	return c
+}
+
+// WithEndpoint sets a config Endpoint value returning a Config pointer for
+// chaining.
+func (c *Config) WithEndpoint(endpoint string) *Config {
+	c.Endpoint = &endpoint
+	return c
+}
+
+// WithEndpointResolver sets a config EndpointResolver value returning a
+// Config pointer for chaining.
+func (c *Config) WithEndpointResolver(resolver endpoints.Resolver) *Config {
+	c.EndpointResolver = resolver
+	return c
+}
+
+// WithRegion sets a config Region value returning a Config pointer for
+// chaining.
+func (c *Config) WithRegion(region string) *Config {
+	c.Region = &region
+	return c
+}
+
+// WithDisableSSL sets a config DisableSSL value returning a Config pointer
+// for chaining.
+func (c *Config) WithDisableSSL(disable bool) *Config {
+	c.DisableSSL = &disable
+	return c
+}
+
+// WithHTTPClient sets a config HTTPClient value returning a Config pointer
+// for chaining.
+func (c *Config) WithHTTPClient(client *http.Client) *Config {
+	c.HTTPClient = client
+	return c
+}
+
+// WithMaxRetries sets a config MaxRetries value returning a Config pointer
+// for chaining.
+func (c *Config) WithMaxRetries(max int) *Config {
+	c.MaxRetries = &max
+	return c
+}
+
+// WithDisableParamValidation sets a config DisableParamValidation value
+// returning a Config pointer for chaining.
+func (c *Config) WithDisableParamValidation(disable bool) *Config {
+	c.DisableParamValidation = &disable
+	return c
+}
+
+// WithDisableComputeChecksums sets a config DisableComputeChecksums value
+// returning a Config pointer for chaining.
+func (c *Config) WithDisableComputeChecksums(disable bool) *Config {
+	c.DisableComputeChecksums = &disable
+	return c
+}
+
+// WithLogLevel sets a config LogLevel value returning a Config pointer for
+// chaining.
+func (c *Config) WithLogLevel(level LogLevelType) *Config {
+	c.LogLevel = &level
+	return c
+}
+
+// WithLogger sets a config Logger value returning a Config pointer for
+// chaining.
+func (c *Config) WithLogger(logger Logger) *Config {
+	c.Logger = logger
+	return c
+}
+
+// WithS3ForcePathStyle sets a config S3ForcePathStyle value returning a Config
+// pointer for chaining.
+func (c *Config) WithS3ForcePathStyle(force bool) *Config {
+	c.S3ForcePathStyle = &force
+	return c
+}
+
+// WithS3Disable100Continue sets a config S3Disable100Continue value returning
+// a Config pointer for chaining.
+func (c *Config) WithS3Disable100Continue(disable bool) *Config {
+	c.S3Disable100Continue = &disable
+	return c
+}
+
+// WithS3UseAccelerate sets a config S3UseAccelerate value returning a Config
+// pointer for chaining.
+func (c *Config) WithS3UseAccelerate(enable bool) *Config {
+	c.S3UseAccelerate = &enable
+	return c
+
+}
+
+// WithS3DisableContentMD5Validation sets a config
+// S3DisableContentMD5Validation value returning a Config pointer for chaining.
+func (c *Config) WithS3DisableContentMD5Validation(enable bool) *Config {
+	c.S3DisableContentMD5Validation = &enable
+	return c
+
+}
+
+// WithUseDualStack sets a config UseDualStack value returning a Config
+// pointer for chaining.
+func (c *Config) WithUseDualStack(enable bool) *Config {
+	c.UseDualStack = &enable
+	return c
+}
+
+// WithEC2MetadataDisableTimeoutOverride sets a config EC2MetadataDisableTimeoutOverride value
+// returning a Config pointer for chaining.
+func (c *Config) WithEC2MetadataDisableTimeoutOverride(enable bool) *Config {
+	c.EC2MetadataDisableTimeoutOverride = &enable
+	return c
+}
+
+// WithSleepDelay overrides the function used to sleep while waiting for the
+// next retry. Defaults to time.Sleep.
+func (c *Config) WithSleepDelay(fn func(time.Duration)) *Config {
+	c.SleepDelay = fn
+	return c
+}
+
+// MergeIn merges the passed in configs into the existing config object.
+func (c *Config) MergeIn(cfgs ...*Config) {
+	for _, other := range cfgs {
+		mergeInConfig(c, other)
+	}
+}
+
+func mergeInConfig(dst *Config, other *Config) {
+	if other == nil {
+		return
+	}
+
+	if other.CredentialsChainVerboseErrors != nil {
+		dst.CredentialsChainVerboseErrors = other.CredentialsChainVerboseErrors
+	}
+
+	if other.Credentials != nil {
+		dst.Credentials = other.Credentials
+	}
+
+	if other.Endpoint != nil {
+		dst.Endpoint = other.Endpoint
+	}
+
+	if other.EndpointResolver != nil {
+		dst.EndpointResolver = other.EndpointResolver
+	}
+
+	if other.Region != nil {
+		dst.Region = other.Region
+	}
+
+	if other.DisableSSL != nil {
+		dst.DisableSSL = other.DisableSSL
+	}
+
+	if other.HTTPClient != nil {
+		dst.HTTPClient = other.HTTPClient
+	}
+
+	if other.LogLevel != nil {
+		dst.LogLevel = other.LogLevel
+	}
+
+	if other.Logger != nil {
+		dst.Logger = other.Logger
+	}
+
+	if other.MaxRetries != nil {
+		dst.MaxRetries = other.MaxRetries
+	}
+
+	if other.Retryer != nil {
+		dst.Retryer = other.Retryer
+	}
+
+	if other.DisableParamValidation != nil {
+		dst.DisableParamValidation = other.DisableParamValidation
+	}
+
+	if other.DisableComputeChecksums != nil {
+		dst.DisableComputeChecksums = other.DisableComputeChecksums
+	}
+
+	if other.S3ForcePathStyle != nil {
+		dst.S3ForcePathStyle = other.S3ForcePathStyle
+	}
+
+	if other.S3Disable100Continue != nil {
+		dst.S3Disable100Continue = other.S3Disable100Continue
+	}
+
+	if other.S3UseAccelerate != nil {
+		dst.S3UseAccelerate = other.S3UseAccelerate
+	}
+
+	if other.S3DisableContentMD5Validation != nil {
+		dst.S3DisableContentMD5Validation = other.S3DisableContentMD5Validation
+	}
+
+	if other.UseDualStack != nil {
+		dst.UseDualStack = other.UseDualStack
+	}
+
+	if other.EC2MetadataDisableTimeoutOverride != nil {
+		dst.EC2MetadataDisableTimeoutOverride = other.EC2MetadataDisableTimeoutOverride
+	}
+
+	if other.SleepDelay != nil {
+		dst.SleepDelay = other.SleepDelay
+	}
+
+	if other.DisableRestProtocolURICleaning != nil {
+		dst.DisableRestProtocolURICleaning = other.DisableRestProtocolURICleaning
+	}
+
+	if other.EnforceShouldRetryCheck != nil {
+		dst.EnforceShouldRetryCheck = other.EnforceShouldRetryCheck
+	}
+}
+
+// Copy will return a shallow copy of the Config object. If any additional
+// configurations are provided they will be merged into the new config returned.
+func (c *Config) Copy(cfgs ...*Config) *Config {
+	dst := &Config{}
+	dst.MergeIn(c)
+
+	for _, cfg := range cfgs {
+		dst.MergeIn(cfg)
+	}
+
+	return dst
+}
@@ -0,0 +1,71 @@
+package aws
+
+import (
+	"time"
+)
+
+// Context is an copy of the Go v1.7 stdlib's context.Context interface.
+// It is represented as a SDK interface to enable you to use the "WithContext"
+// API methods with Go v1.6 and a Context type such as golang.org/x/net/context.
+//
+// See https://golang.org/pkg/context on how to use contexts.
+type Context interface {
+	// Deadline returns the time when work done on behalf of this context
+	// should be canceled. Deadline returns ok==false when no deadline is
+	// set. Successive calls to Deadline return the same results.
+	Deadline() (deadline time.Time, ok bool)
+
+	// Done returns a channel that's closed when work done on behalf of this
+	// context should be canceled. Done may return nil if this context can
+	// never be canceled. Successive calls to Done return the same value.
+	Done() <-chan struct{}
+
+	// Err returns a non-nil error value after Done is closed. Err returns
+	// Canceled if the context was canceled or DeadlineExceeded if the
+	// context's deadline passed. No other values for Err are defined.
+	// After Done is closed, successive calls to Err return the same value.
+	Err() error
+
+	// Value returns the value associated with this context for key, or nil
+	// if no value is associated with key. Successive calls to Value with
+	// the same key returns the same result.
+	//
+	// Use context values only for request-scoped data that transits
+	// processes and API boundaries, not for passing optional parameters to
+	// functions.
+	Value(key interface{}) interface{}
+}
+
+// BackgroundContext returns a context that will never be canceled, has no
+// values, and no deadline. This context is used by the SDK to provide
+// backwards compatibility with non-context API operations and functionality.
+//
+// Go 1.6 and before:
+// This context function is equivalent to context.Background in the Go stdlib.
+//
+// Go 1.7 and later:
+// The context returned will be the value returned by context.Background()
+//
+// See https://golang.org/pkg/context for more information on Contexts.
+func BackgroundContext() Context {
+	return backgroundCtx
+}
+
+// SleepWithContext will wait for the timer duration to expire, or the context
+// is canceled. Which ever happens first. If the context is canceled the Context's
+// error will be returned.
+//
+// Expects Context to always return a non-nil error if the Done channel is closed.
+func SleepWithContext(ctx Context, dur time.Duration) error {
+	t := time.NewTimer(dur)
+	defer t.Stop()
+
+	select {
+	case <-t.C:
+		break
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+
+	return nil
+}
@@ -0,0 +1,41 @@
+// +build !go1.7
+
+package aws
+
+import "time"
+
+// An emptyCtx is a copy of the Go 1.7 context.emptyCtx type. This is copied to
+// provide a 1.6 and 1.5 safe version of context that is compatible with Go
+// 1.7's Context.
+//
+// An emptyCtx is never canceled, has no values, and has no deadline. It is not
+// struct{}, since vars of this type must have distinct addresses.
+type emptyCtx int
+
+func (*emptyCtx) Deadline() (deadline time.Time, ok bool) {
+	return
+}
+
+func (*emptyCtx) Done() <-chan struct{} {
+	return nil
+}
+
+func (*emptyCtx) Err() error {
+	return nil
+}
+
+func (*emptyCtx) Value(key interface{}) interface{} {
+	return nil
+}
+
+func (e *emptyCtx) String() string {
+	switch e {
+	case backgroundCtx:
+		return "aws.BackgroundContext"
+	}
+	return "unknown empty Context"
+}
+
+var (
+	backgroundCtx = new(emptyCtx)
+)
@@ -0,0 +1,9 @@
+// +build go1.7
+
+package aws
+
+import "context"
+
+var (
+	backgroundCtx = context.Background()
+)
@@ -0,0 +1,387 @@
+package aws
+
+import "time"
+
+// String returns a pointer to the string value passed in.
+func String(v string) *string {
+	return &v
+}
+
+// StringValue returns the value of the string pointer passed in or
+// "" if the pointer is nil.
+func StringValue(v *string) string {
+	if v != nil {
+		return *v
+	}
+	return ""
+}
+
+// StringSlice converts a slice of string values into a slice of
+// string pointers
+func StringSlice(src []string) []*string {
+	dst := make([]*string, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// StringValueSlice converts a slice of string pointers into a slice of
+// string values
+func StringValueSlice(src []*string) []string {
+	dst := make([]string, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// StringMap converts a string map of string values into a string
+// map of string pointers
+func StringMap(src map[string]string) map[string]*string {
+	dst := make(map[string]*string)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// StringValueMap converts a string map of string pointers into a string
+// map of string values
+func StringValueMap(src map[string]*string) map[string]string {
+	dst := make(map[string]string)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Bool returns a pointer to the bool value passed in.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// BoolValue returns the value of the bool pointer passed in or
+// false if the pointer is nil.
+func BoolValue(v *bool) bool {
+	if v != nil {
+		return *v
+	}
+	return false
+}
+
+// BoolSlice converts a slice of bool values into a slice of
+// bool pointers
+func BoolSlice(src []bool) []*bool {
+	dst := make([]*bool, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// BoolValueSlice converts a slice of bool pointers into a slice of
+// bool values
+func BoolValueSlice(src []*bool) []bool {
+	dst := make([]bool, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// BoolMap converts a string map of bool values into a string
+// map of bool pointers
+func BoolMap(src map[string]bool) map[string]*bool {
+	dst := make(map[string]*bool)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// BoolValueMap converts a string map of bool pointers into a string
+// map of bool values
+func BoolValueMap(src map[string]*bool) map[string]bool {
+	dst := make(map[string]bool)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Int returns a pointer to the int value passed in.
+func Int(v int) *int {
+	return &v
+}
+
+// IntValue returns the value of the int pointer passed in or
+// 0 if the pointer is nil.
+func IntValue(v *int) int {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// IntSlice converts a slice of int values into a slice of
+// int pointers
+func IntSlice(src []int) []*int {
+	dst := make([]*int, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// IntValueSlice converts a slice of int pointers into a slice of
+// int values
+func IntValueSlice(src []*int) []int {
+	dst := make([]int, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// IntMap converts a string map of int values into a string
+// map of int pointers
+func IntMap(src map[string]int) map[string]*int {
+	dst := make(map[string]*int)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// IntValueMap converts a string map of int pointers into a string
+// map of int values
+func IntValueMap(src map[string]*int) map[string]int {
+	dst := make(map[string]int)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Int64 returns a pointer to the int64 value passed in.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Int64Value returns the value of the int64 pointer passed in or
+// 0 if the pointer is nil.
+func Int64Value(v *int64) int64 {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// Int64Slice converts a slice of int64 values into a slice of
+// int64 pointers
+func Int64Slice(src []int64) []*int64 {
+	dst := make([]*int64, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// Int64ValueSlice converts a slice of int64 pointers into a slice of
+// int64 values
+func Int64ValueSlice(src []*int64) []int64 {
+	dst := make([]int64, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// Int64Map converts a string map of int64 values into a string
+// map of int64 pointers
+func Int64Map(src map[string]int64) map[string]*int64 {
+	dst := make(map[string]*int64)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// Int64ValueMap converts a string map of int64 pointers into a string
+// map of int64 values
+func Int64ValueMap(src map[string]*int64) map[string]int64 {
+	dst := make(map[string]int64)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Float64 returns a pointer to the float64 value passed in.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Float64Value returns the value of the float64 pointer passed in or
+// 0 if the pointer is nil.
+func Float64Value(v *float64) float64 {
+	if v != nil {
+		return *v
+	}
+	return 0
+}
+
+// Float64Slice converts a slice of float64 values into a slice of
+// float64 pointers
+func Float64Slice(src []float64) []*float64 {
+	dst := make([]*float64, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// Float64ValueSlice converts a slice of float64 pointers into a slice of
+// float64 values
+func Float64ValueSlice(src []*float64) []float64 {
+	dst := make([]float64, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// Float64Map converts a string map of float64 values into a string
+// map of float64 pointers
+func Float64Map(src map[string]float64) map[string]*float64 {
+	dst := make(map[string]*float64)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// Float64ValueMap converts a string map of float64 pointers into a string
+// map of float64 values
+func Float64ValueMap(src map[string]*float64) map[string]float64 {
+	dst := make(map[string]float64)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
+
+// Time returns a pointer to the time.Time value passed in.
+func Time(v time.Time) *time.Time {
+	return &v
+}
+
+// TimeValue returns the value of the time.Time pointer passed in or
+// time.Time{} if the pointer is nil.
+func TimeValue(v *time.Time) time.Time {
+	if v != nil {
+		return *v
+	}
+	return time.Time{}
+}
+
+// SecondsTimeValue converts an int64 pointer to a time.Time value
+// representing seconds since Epoch or time.Time{} if the pointer is nil.
+func SecondsTimeValue(v *int64) time.Time {
+	if v != nil {
+		return time.Unix((*v / 1000), 0)
+	}
+	return time.Time{}
+}
+
+// MillisecondsTimeValue converts an int64 pointer to a time.Time value
+// representing milliseconds sinch Epoch or time.Time{} if the pointer is nil.
+func MillisecondsTimeValue(v *int64) time.Time {
+	if v != nil {
+		return time.Unix(0, (*v * 1000000))
+	}
+	return time.Time{}
+}
+
+// TimeUnixMilli returns a Unix timestamp in milliseconds from "January 1, 1970 UTC".
+// The result is undefined if the Unix time cannot be represented by an int64.
+// Which includes calling TimeUnixMilli on a zero Time is undefined.
+//
+// This utility is useful for service API's such as CloudWatch Logs which require
+// their unix time values to be in milliseconds.
+//
+// See Go stdlib https://golang.org/pkg/time/#Time.UnixNano for more information.
+func TimeUnixMilli(t time.Time) int64 {
+	return t.UnixNano() / int64(time.Millisecond/time.Nanosecond)
+}
+
+// TimeSlice converts a slice of time.Time values into a slice of
+// time.Time pointers
+func TimeSlice(src []time.Time) []*time.Time {
+	dst := make([]*time.Time, len(src))
+	for i := 0; i < len(src); i++ {
+		dst[i] = &(src[i])
+	}
+	return dst
+}
+
+// TimeValueSlice converts a slice of time.Time pointers into a slice of
+// time.Time values
+func TimeValueSlice(src []*time.Time) []time.Time {
+	dst := make([]time.Time, len(src))
+	for i := 0; i < len(src); i++ {
+		if src[i] != nil {
+			dst[i] = *(src[i])
+		}
+	}
+	return dst
+}
+
+// TimeMap converts a string map of time.Time values into a string
+// map of time.Time pointers
+func TimeMap(src map[string]time.Time) map[string]*time.Time {
+	dst := make(map[string]*time.Time)
+	for k, val := range src {
+		v := val
+		dst[k] = &v
+	}
+	return dst
+}
+
+// TimeValueMap converts a string map of time.Time pointers into a string
+// map of time.Time values
+func TimeValueMap(src map[string]*time.Time) map[string]time.Time {
+	dst := make(map[string]time.Time)
+	for k, val := range src {
+		if val != nil {
+			dst[k] = *val
+		}
+	}
+	return dst
+}
@@ -0,0 +1,228 @@
+package corehandlers
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// Interface for matching types which also have a Len method.
+type lener interface {
+	Len() int
+}
+
+// BuildContentLengthHandler builds the content length of a request based on the body,
+// or will use the HTTPRequest.Header's "Content-Length" if defined. If unable
+// to determine request body length and no "Content-Length" was specified it will panic.
+//
+// The Content-Length will only be added to the request if the length of the body
+// is greater than 0. If the body is empty or the current `Content-Length`
+// header is <= 0, the header will also be stripped.
+var BuildContentLengthHandler = request.NamedHandler{Name: "core.BuildContentLengthHandler", Fn: func(r *request.Request) {
+	var length int64
+
+	if slength := r.HTTPRequest.Header.Get("Content-Length"); slength != "" {
+		length, _ = strconv.ParseInt(slength, 10, 64)
+	} else {
+		if r.Body != nil {
+			var err error
+			length, err = aws.SeekerLen(r.Body)
+			if err != nil {
+				r.Error = awserr.New(request.ErrCodeSerialization, "failed to get request body's length", err)
+				return
+			}
+		}
+	}
+
+	if length > 0 {
+		r.HTTPRequest.ContentLength = length
+		r.HTTPRequest.Header.Set("Content-Length", fmt.Sprintf("%d", length))
+	} else {
+		r.HTTPRequest.ContentLength = 0
+		r.HTTPRequest.Header.Del("Content-Length")
+	}
+}}
+
+var reStatusCode = regexp.MustCompile(`^(\d{3})`)
+
+// ValidateReqSigHandler is a request handler to ensure that the request's
+// signature doesn't expire before it is sent. This can happen when a request
+// is built and signed significantly before it is sent. Or significant delays
+// occur when retrying requests that would cause the signature to expire.
+var ValidateReqSigHandler = request.NamedHandler{
+	Name: "core.ValidateReqSigHandler",
+	Fn: func(r *request.Request) {
+		// Unsigned requests are not signed
+		if r.Config.Credentials == credentials.AnonymousCredentials {
+			return
+		}
+
+		signedTime := r.Time
+		if !r.LastSignedAt.IsZero() {
+			signedTime = r.LastSignedAt
+		}
+
+		// 10 minutes to allow for some clock skew/delays in transmission.
+		// Would be improved with aws/aws-sdk-go#423
+		if signedTime.Add(10 * time.Minute).After(time.Now()) {
+			return
+		}
+
+		fmt.Println("request expired, resigning")
+		r.Sign()
+	},
+}
+
+// SendHandler is a request handler to send service request using HTTP client.
+var SendHandler = request.NamedHandler{
+	Name: "core.SendHandler",
+	Fn: func(r *request.Request) {
+		sender := sendFollowRedirects
+		if r.DisableFollowRedirects {
+			sender = sendWithoutFollowRedirects
+		}
+
+		if request.NoBody == r.HTTPRequest.Body {
+			// Strip off the request body if the NoBody reader was used as a
+			// place holder for a request body. This prevents the SDK from
+			// making requests with a request body when it would be invalid
+			// to do so.
+			//
+			// Use a shallow copy of the http.Request to ensure the race condition
+			// of transport on Body will not trigger
+			reqOrig, reqCopy := r.HTTPRequest, *r.HTTPRequest
+			reqCopy.Body = nil
+			r.HTTPRequest = &reqCopy
+			defer func() {
+				r.HTTPRequest = reqOrig
+			}()
+		}
+
+		var err error
+		r.HTTPResponse, err = sender(r)
+		if err != nil {
+			handleSendError(r, err)
+		}
+	},
+}
+
+func sendFollowRedirects(r *request.Request) (*http.Response, error) {
+	return r.Config.HTTPClient.Do(r.HTTPRequest)
+}
+
+func sendWithoutFollowRedirects(r *request.Request) (*http.Response, error) {
+	transport := r.Config.HTTPClient.Transport
+	if transport == nil {
+		transport = http.DefaultTransport
+	}
+
+	return transport.RoundTrip(r.HTTPRequest)
+}
+
+func handleSendError(r *request.Request, err error) {
+	// Prevent leaking if an HTTPResponse was returned. Clean up
+	// the body.
+	if r.HTTPResponse != nil {
+		r.HTTPResponse.Body.Close()
+	}
+	// Capture the case where url.Error is returned for error processing
+	// response. e.g. 301 without location header comes back as string
+	// error and r.HTTPResponse is nil. Other URL redirect errors will
+	// comeback in a similar method.
+	if e, ok := err.(*url.Error); ok && e.Err != nil {
+		if s := reStatusCode.FindStringSubmatch(e.Err.Error()); s != nil {
+			code, _ := strconv.ParseInt(s[1], 10, 64)
+			r.HTTPResponse = &http.Response{
+				StatusCode: int(code),
+				Status:     http.StatusText(int(code)),
+				Body:       ioutil.NopCloser(bytes.NewReader([]byte{})),
+			}
+			return
+		}
+	}
+	if r.HTTPResponse == nil {
+		// Add a dummy request response object to ensure the HTTPResponse
+		// value is consistent.
+		r.HTTPResponse = &http.Response{
+			StatusCode: int(0),
+			Status:     http.StatusText(int(0)),
+			Body:       ioutil.NopCloser(bytes.NewReader([]byte{})),
+		}
+	}
+	// Catch all other request errors.
+	r.Error = awserr.New("RequestError", "send request failed", err)
+	r.Retryable = aws.Bool(true) // network errors are retryable
+
+	// Override the error with a context canceled error, if that was canceled.
+	ctx := r.Context()
+	select {
+	case <-ctx.Done():
+		r.Error = awserr.New(request.CanceledErrorCode,
+			"request context canceled", ctx.Err())
+		r.Retryable = aws.Bool(false)
+	default:
+	}
+}
+
+// ValidateResponseHandler is a request handler to validate service response.
+var ValidateResponseHandler = request.NamedHandler{Name: "core.ValidateResponseHandler", Fn: func(r *request.Request) {
+	if r.HTTPResponse.StatusCode == 0 || r.HTTPResponse.StatusCode >= 300 {
+		// this may be replaced by an UnmarshalError handler
+		r.Error = awserr.New("UnknownError", "unknown error", nil)
+	}
+}}
+
+// AfterRetryHandler performs final checks to determine if the request should
+// be retried and how long to delay.
+var AfterRetryHandler = request.NamedHandler{Name: "core.AfterRetryHandler", Fn: func(r *request.Request) {
+	// If one of the other handlers already set the retry state
+	// we don't want to override it based on the service's state
+	if r.Retryable == nil || aws.BoolValue(r.Config.EnforceShouldRetryCheck) {
+		r.Retryable = aws.Bool(r.ShouldRetry(r))
+	}
+
+	if r.WillRetry() {
+		r.RetryDelay = r.RetryRules(r)
+
+		if sleepFn := r.Config.SleepDelay; sleepFn != nil {
+			// Support SleepDelay for backwards compatibility and testing
+			sleepFn(r.RetryDelay)
+		} else if err := aws.SleepWithContext(r.Context(), r.RetryDelay); err != nil {
+			r.Error = awserr.New(request.CanceledErrorCode,
+				"request context canceled", err)
+			r.Retryable = aws.Bool(false)
+			return
+		}
+
+		// when the expired token exception occurs the credentials
+		// need to be expired locally so that the next request to
+		// get credentials will trigger a credentials refresh.
+		if r.IsErrorExpired() {
+			r.Config.Credentials.Expire()
+		}
+
+		r.RetryCount++
+		r.Error = nil
+	}
+}}
+
+// ValidateEndpointHandler is a request handler to validate a request had the
+// appropriate Region and Endpoint set. Will set r.Error if the endpoint or
+// region is not valid.
+var ValidateEndpointHandler = request.NamedHandler{Name: "core.ValidateEndpointHandler", Fn: func(r *request.Request) {
+	if r.ClientInfo.SigningRegion == "" && aws.StringValue(r.Config.Region) == "" {
+		r.Error = aws.ErrMissingRegion
+	} else if r.ClientInfo.Endpoint == "" {
+		r.Error = aws.ErrMissingEndpoint
+	}
+}}
@@ -0,0 +1,17 @@
+package corehandlers
+
+import "github.com/aws/aws-sdk-go/aws/request"
+
+// ValidateParametersHandler is a request handler to validate the input parameters.
+// Validating parameters only has meaning if done prior to the request being sent.
+var ValidateParametersHandler = request.NamedHandler{Name: "core.ValidateParametersHandler", Fn: func(r *request.Request) {
+	if !r.ParamsFilled() {
+		return
+	}
+
+	if v, ok := r.Params.(request.Validator); ok {
+		if err := v.Validate(); err != nil {
+			r.Error = err
+		}
+	}
+}}
@@ -0,0 +1,37 @@
+package corehandlers
+
+import (
+	"os"
+	"runtime"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// SDKVersionUserAgentHandler is a request handler for adding the SDK Version
+// to the user agent.
+var SDKVersionUserAgentHandler = request.NamedHandler{
+	Name: "core.SDKVersionUserAgentHandler",
+	Fn: request.MakeAddToUserAgentHandler(aws.SDKName, aws.SDKVersion,
+		runtime.Version(), runtime.GOOS, runtime.GOARCH),
+}
+
+const execEnvVar = `AWS_EXECUTION_ENV`
+const execEnvUAKey = `exec_env`
+
+// AddHostExecEnvUserAgentHander is a request handler appending the SDK's
+// execution environment to the user agent.
+//
+// If the environment variable AWS_EXECUTION_ENV is set, its value will be
+// appended to the user agent string.
+var AddHostExecEnvUserAgentHander = request.NamedHandler{
+	Name: "core.AddHostExecEnvUserAgentHander",
+	Fn: func(r *request.Request) {
+		v := os.Getenv(execEnvVar)
+		if len(v) == 0 {
+			return
+		}
+
+		request.AddToUserAgent(r, execEnvUAKey+"/"+v)
+	},
+}
@@ -0,0 +1,102 @@
+package credentials
+
+import (
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+var (
+	// ErrNoValidProvidersFoundInChain Is returned when there are no valid
+	// providers in the ChainProvider.
+	//
+	// This has been deprecated. For verbose error messaging set
+	// aws.Config.CredentialsChainVerboseErrors to true
+	//
+	// @readonly
+	ErrNoValidProvidersFoundInChain = awserr.New("NoCredentialProviders",
+		`no valid providers in chain. Deprecated.
+	For verbose messaging see aws.Config.CredentialsChainVerboseErrors`,
+		nil)
+)
+
+// A ChainProvider will search for a provider which returns credentials
+// and cache that provider until Retrieve is called again.
+//
+// The ChainProvider provides a way of chaining multiple providers together
+// which will pick the first available using priority order of the Providers
+// in the list.
+//
+// If none of the Providers retrieve valid credentials Value, ChainProvider's
+// Retrieve() will return the error ErrNoValidProvidersFoundInChain.
+//
+// If a Provider is found which returns valid credentials Value ChainProvider
+// will cache that Provider for all calls to IsExpired(), until Retrieve is
+// called again.
+//
+// Example of ChainProvider to be used with an EnvProvider and EC2RoleProvider.
+// In this example EnvProvider will first check if any credentials are available
+// via the environment variables. If there are none ChainProvider will check
+// the next Provider in the list, EC2RoleProvider in this case. If EC2RoleProvider
+// does not return any credentials ChainProvider will return the error
+// ErrNoValidProvidersFoundInChain
+//
+//     creds := credentials.NewChainCredentials(
+//         []credentials.Provider{
+//             &credentials.EnvProvider{},
+//             &ec2rolecreds.EC2RoleProvider{
+//                 Client: ec2metadata.New(sess),
+//             },
+//         })
+//
+//     // Usage of ChainCredentials with aws.Config
+//     svc := ec2.New(session.Must(session.NewSession(&aws.Config{
+//       Credentials: creds,
+//     })))
+//
+type ChainProvider struct {
+	Providers     []Provider
+	curr          Provider
+	VerboseErrors bool
+}
+
+// NewChainCredentials returns a pointer to a new Credentials object
+// wrapping a chain of providers.
+func NewChainCredentials(providers []Provider) *Credentials {
+	return NewCredentials(&ChainProvider{
+		Providers: append([]Provider{}, providers...),
+	})
+}
+
+// Retrieve returns the credentials value or error if no provider returned
+// without error.
+//
+// If a provider is found it will be cached and any calls to IsExpired()
+// will return the expired state of the cached provider.
+func (c *ChainProvider) Retrieve() (Value, error) {
+	var errs []error
+	for _, p := range c.Providers {
+		creds, err := p.Retrieve()
+		if err == nil {
+			c.curr = p
+			return creds, nil
+		}
+		errs = append(errs, err)
+	}
+	c.curr = nil
+
+	var err error
+	err = ErrNoValidProvidersFoundInChain
+	if c.VerboseErrors {
+		err = awserr.NewBatchError("NoCredentialProviders", "no valid providers in chain", errs)
+	}
+	return Value{}, err
+}
+
+// IsExpired will returned the expired state of the currently cached provider
+// if there is one.  If there is no current provider, true will be returned.
+func (c *ChainProvider) IsExpired() bool {
+	if c.curr != nil {
+		return c.curr.IsExpired()
+	}
+
+	return true
+}
@@ -0,0 +1,246 @@
+// Package credentials provides credential retrieval and management
+//
+// The Credentials is the primary method of getting access to and managing
+// credentials Values. Using dependency injection retrieval of the credential
+// values is handled by a object which satisfies the Provider interface.
+//
+// By default the Credentials.Get() will cache the successful result of a
+// Provider's Retrieve() until Provider.IsExpired() returns true. At which
+// point Credentials will call Provider's Retrieve() to get new credential Value.
+//
+// The Provider is responsible for determining when credentials Value have expired.
+// It is also important to note that Credentials will always call Retrieve the
+// first time Credentials.Get() is called.
+//
+// Example of using the environment variable credentials.
+//
+//     creds := credentials.NewEnvCredentials()
+//
+//     // Retrieve the credentials value
+//     credValue, err := creds.Get()
+//     if err != nil {
+//         // handle error
+//     }
+//
+// Example of forcing credentials to expire and be refreshed on the next Get().
+// This may be helpful to proactively expire credentials and refresh them sooner
+// than they would naturally expire on their own.
+//
+//     creds := credentials.NewCredentials(&ec2rolecreds.EC2RoleProvider{})
+//     creds.Expire()
+//     credsValue, err := creds.Get()
+//     // New credentials will be retrieved instead of from cache.
+//
+//
+// Custom Provider
+//
+// Each Provider built into this package also provides a helper method to generate
+// a Credentials pointer setup with the provider. To use a custom Provider just
+// create a type which satisfies the Provider interface and pass it to the
+// NewCredentials method.
+//
+//     type MyProvider struct{}
+//     func (m *MyProvider) Retrieve() (Value, error) {...}
+//     func (m *MyProvider) IsExpired() bool {...}
+//
+//     creds := credentials.NewCredentials(&MyProvider{})
+//     credValue, err := creds.Get()
+//
+package credentials
+
+import (
+	"sync"
+	"time"
+)
+
+// AnonymousCredentials is an empty Credential object that can be used as
+// dummy placeholder credentials for requests that do not need signed.
+//
+// This Credentials can be used to configure a service to not sign requests
+// when making service API calls. For example, when accessing public
+// s3 buckets.
+//
+//     svc := s3.New(session.Must(session.NewSession(&aws.Config{
+//       Credentials: credentials.AnonymousCredentials,
+//     })))
+//     // Access public S3 buckets.
+//
+// @readonly
+var AnonymousCredentials = NewStaticCredentials("", "", "")
+
+// A Value is the AWS credentials value for individual credential fields.
+type Value struct {
+	// AWS Access key ID
+	AccessKeyID string
+
+	// AWS Secret Access Key
+	SecretAccessKey string
+
+	// AWS Session Token
+	SessionToken string
+
+	// Provider used to get credentials
+	ProviderName string
+}
+
+// A Provider is the interface for any component which will provide credentials
+// Value. A provider is required to manage its own Expired state, and what to
+// be expired means.
+//
+// The Provider should not need to implement its own mutexes, because
+// that will be managed by Credentials.
+type Provider interface {
+	// Retrieve returns nil if it successfully retrieved the value.
+	// Error is returned if the value were not obtainable, or empty.
+	Retrieve() (Value, error)
+
+	// IsExpired returns if the credentials are no longer valid, and need
+	// to be retrieved.
+	IsExpired() bool
+}
+
+// An ErrorProvider is a stub credentials provider that always returns an error
+// this is used by the SDK when construction a known provider is not possible
+// due to an error.
+type ErrorProvider struct {
+	// The error to be returned from Retrieve
+	Err error
+
+	// The provider name to set on the Retrieved returned Value
+	ProviderName string
+}
+
+// Retrieve will always return the error that the ErrorProvider was created with.
+func (p ErrorProvider) Retrieve() (Value, error) {
+	return Value{ProviderName: p.ProviderName}, p.Err
+}
+
+// IsExpired will always return not expired.
+func (p ErrorProvider) IsExpired() bool {
+	return false
+}
+
+// A Expiry provides shared expiration logic to be used by credentials
+// providers to implement expiry functionality.
+//
+// The best method to use this struct is as an anonymous field within the
+// provider's struct.
+//
+// Example:
+//     type EC2RoleProvider struct {
+//         Expiry
+//         ...
+//     }
+type Expiry struct {
+	// The date/time when to expire on
+	expiration time.Time
+
+	// If set will be used by IsExpired to determine the current time.
+	// Defaults to time.Now if CurrentTime is not set.  Available for testing
+	// to be able to mock out the current time.
+	CurrentTime func() time.Time
+}
+
+// SetExpiration sets the expiration IsExpired will check when called.
+//
+// If window is greater than 0 the expiration time will be reduced by the
+// window value.
+//
+// Using a window is helpful to trigger credentials to expire sooner than
+// the expiration time given to ensure no requests are made with expired
+// tokens.
+func (e *Expiry) SetExpiration(expiration time.Time, window time.Duration) {
+	e.expiration = expiration
+	if window > 0 {
+		e.expiration = e.expiration.Add(-window)
+	}
+}
+
+// IsExpired returns if the credentials are expired.
+func (e *Expiry) IsExpired() bool {
+	if e.CurrentTime == nil {
+		e.CurrentTime = time.Now
+	}
+	return e.expiration.Before(e.CurrentTime())
+}
+
+// A Credentials provides synchronous safe retrieval of AWS credentials Value.
+// Credentials will cache the credentials value until they expire. Once the value
+// expires the next Get will attempt to retrieve valid credentials.
+//
+// Credentials is safe to use across multiple goroutines and will manage the
+// synchronous state so the Providers do not need to implement their own
+// synchronization.
+//
+// The first Credentials.Get() will always call Provider.Retrieve() to get the
+// first instance of the credentials Value. All calls to Get() after that
+// will return the cached credentials Value until IsExpired() returns true.
+type Credentials struct {
+	creds        Value
+	forceRefresh bool
+	m            sync.Mutex
+
+	provider Provider
+}
+
+// NewCredentials returns a pointer to a new Credentials with the provider set.
+func NewCredentials(provider Provider) *Credentials {
+	return &Credentials{
+		provider:     provider,
+		forceRefresh: true,
+	}
+}
+
+// Get returns the credentials value, or error if the credentials Value failed
+// to be retrieved.
+//
+// Will return the cached credentials Value if it has not expired. If the
+// credentials Value has expired the Provider's Retrieve() will be called
+// to refresh the credentials.
+//
+// If Credentials.Expire() was called the credentials Value will be force
+// expired, and the next call to Get() will cause them to be refreshed.
+func (c *Credentials) Get() (Value, error) {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	if c.isExpired() {
+		creds, err := c.provider.Retrieve()
+		if err != nil {
+			return Value{}, err
+		}
+		c.creds = creds
+		c.forceRefresh = false
+	}
+
+	return c.creds, nil
+}
+
+// Expire expires the credentials and forces them to be retrieved on the
+// next call to Get().
+//
+// This will override the Provider's expired state, and force Credentials
+// to call the Provider's Retrieve().
+func (c *Credentials) Expire() {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	c.forceRefresh = true
+}
+
+// IsExpired returns if the credentials are no longer valid, and need
+// to be retrieved.
+//
+// If the Credentials were forced to be expired with Expire() this will
+// reflect that override.
+func (c *Credentials) IsExpired() bool {
+	c.m.Lock()
+	defer c.m.Unlock()
+
+	return c.isExpired()
+}
+
+// isExpired helper method wrapping the definition of expired credentials.
+func (c *Credentials) isExpired() bool {
+	return c.forceRefresh || c.provider.IsExpired()
+}
@@ -0,0 +1,178 @@
+package ec2rolecreds
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"path"
+	"strings"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/client"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/ec2metadata"
+)
+
+// ProviderName provides a name of EC2Role provider
+const ProviderName = "EC2RoleProvider"
+
+// A EC2RoleProvider retrieves credentials from the EC2 service, and keeps track if
+// those credentials are expired.
+//
+// Example how to configure the EC2RoleProvider with custom http Client, Endpoint
+// or ExpiryWindow
+//
+//     p := &ec2rolecreds.EC2RoleProvider{
+//         // Pass in a custom timeout to be used when requesting
+//         // IAM EC2 Role credentials.
+//         Client: ec2metadata.New(sess, aws.Config{
+//             HTTPClient: &http.Client{Timeout: 10 * time.Second},
+//         }),
+//
+//         // Do not use early expiry of credentials. If a non zero value is
+//         // specified the credentials will be expired early
+//         ExpiryWindow: 0,
+//     }
+type EC2RoleProvider struct {
+	credentials.Expiry
+
+	// Required EC2Metadata client to use when connecting to EC2 metadata service.
+	Client *ec2metadata.EC2Metadata
+
+	// ExpiryWindow will allow the credentials to trigger refreshing prior to
+	// the credentials actually expiring. This is beneficial so race conditions
+	// with expiring credentials do not cause request to fail unexpectedly
+	// due to ExpiredTokenException exceptions.
+	//
+	// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
+	// 10 seconds before the credentials are actually expired.
+	//
+	// If ExpiryWindow is 0 or less it will be ignored.
+	ExpiryWindow time.Duration
+}
+
+// NewCredentials returns a pointer to a new Credentials object wrapping
+// the EC2RoleProvider. Takes a ConfigProvider to create a EC2Metadata client.
+// The ConfigProvider is satisfied by the session.Session type.
+func NewCredentials(c client.ConfigProvider, options ...func(*EC2RoleProvider)) *credentials.Credentials {
+	p := &EC2RoleProvider{
+		Client: ec2metadata.New(c),
+	}
+
+	for _, option := range options {
+		option(p)
+	}
+
+	return credentials.NewCredentials(p)
+}
+
+// NewCredentialsWithClient returns a pointer to a new Credentials object wrapping
+// the EC2RoleProvider. Takes a EC2Metadata client to use when connecting to EC2
+// metadata service.
+func NewCredentialsWithClient(client *ec2metadata.EC2Metadata, options ...func(*EC2RoleProvider)) *credentials.Credentials {
+	p := &EC2RoleProvider{
+		Client: client,
+	}
+
+	for _, option := range options {
+		option(p)
+	}
+
+	return credentials.NewCredentials(p)
+}
+
+// Retrieve retrieves credentials from the EC2 service.
+// Error will be returned if the request fails, or unable to extract
+// the desired credentials.
+func (m *EC2RoleProvider) Retrieve() (credentials.Value, error) {
+	credsList, err := requestCredList(m.Client)
+	if err != nil {
+		return credentials.Value{ProviderName: ProviderName}, err
+	}
+
+	if len(credsList) == 0 {
+		return credentials.Value{ProviderName: ProviderName}, awserr.New("EmptyEC2RoleList", "empty EC2 Role list", nil)
+	}
+	credsName := credsList[0]
+
+	roleCreds, err := requestCred(m.Client, credsName)
+	if err != nil {
+		return credentials.Value{ProviderName: ProviderName}, err
+	}
+
+	m.SetExpiration(roleCreds.Expiration, m.ExpiryWindow)
+
+	return credentials.Value{
+		AccessKeyID:     roleCreds.AccessKeyID,
+		SecretAccessKey: roleCreds.SecretAccessKey,
+		SessionToken:    roleCreds.Token,
+		ProviderName:    ProviderName,
+	}, nil
+}
+
+// A ec2RoleCredRespBody provides the shape for unmarshaling credential
+// request responses.
+type ec2RoleCredRespBody struct {
+	// Success State
+	Expiration      time.Time
+	AccessKeyID     string
+	SecretAccessKey string
+	Token           string
+
+	// Error state
+	Code    string
+	Message string
+}
+
+const iamSecurityCredsPath = "/iam/security-credentials"
+
+// requestCredList requests a list of credentials from the EC2 service.
+// If there are no credentials, or there is an error making or receiving the request
+func requestCredList(client *ec2metadata.EC2Metadata) ([]string, error) {
+	resp, err := client.GetMetadata(iamSecurityCredsPath)
+	if err != nil {
+		return nil, awserr.New("EC2RoleRequestError", "no EC2 instance role found", err)
+	}
+
+	credsList := []string{}
+	s := bufio.NewScanner(strings.NewReader(resp))
+	for s.Scan() {
+		credsList = append(credsList, s.Text())
+	}
+
+	if err := s.Err(); err != nil {
+		return nil, awserr.New("SerializationError", "failed to read EC2 instance role from metadata service", err)
+	}
+
+	return credsList, nil
+}
+
+// requestCred requests the credentials for a specific credentials from the EC2 service.
+//
+// If the credentials cannot be found, or there is an error reading the response
+// and error will be returned.
+func requestCred(client *ec2metadata.EC2Metadata, credsName string) (ec2RoleCredRespBody, error) {
+	resp, err := client.GetMetadata(path.Join(iamSecurityCredsPath, credsName))
+	if err != nil {
+		return ec2RoleCredRespBody{},
+			awserr.New("EC2RoleRequestError",
+				fmt.Sprintf("failed to get %s EC2 instance role credentials", credsName),
+				err)
+	}
+
+	respCreds := ec2RoleCredRespBody{}
+	if err := json.NewDecoder(strings.NewReader(resp)).Decode(&respCreds); err != nil {
+		return ec2RoleCredRespBody{},
+			awserr.New("SerializationError",
+				fmt.Sprintf("failed to decode %s EC2 instance role credentials", credsName),
+				err)
+	}
+
+	if respCreds.Code != "Success" {
+		// If an error code was returned something failed requesting the role.
+		return ec2RoleCredRespBody{}, awserr.New(respCreds.Code, respCreds.Message, nil)
+	}
+
+	return respCreds, nil
+}
@@ -0,0 +1,191 @@
+// Package endpointcreds provides support for retrieving credentials from an
+// arbitrary HTTP endpoint.
+//
+// The credentials endpoint Provider can receive both static and refreshable
+// credentials that will expire. Credentials are static when an "Expiration"
+// value is not provided in the endpoint's response.
+//
+// Static credentials will never expire once they have been retrieved. The format
+// of the static credentials response:
+//    {
+//        "AccessKeyId" : "MUA...",
+//        "SecretAccessKey" : "/7PC5om....",
+//    }
+//
+// Refreshable credentials will expire within the "ExpiryWindow" of the Expiration
+// value in the response. The format of the refreshable credentials response:
+//    {
+//        "AccessKeyId" : "MUA...",
+//        "SecretAccessKey" : "/7PC5om....",
+//        "Token" : "AQoDY....=",
+//        "Expiration" : "2016-02-25T06:03:31Z"
+//    }
+//
+// Errors should be returned in the following format and only returned with 400
+// or 500 HTTP status codes.
+//    {
+//        "code": "ErrorCode",
+//        "message": "Helpful error message."
+//    }
+package endpointcreds
+
+import (
+	"encoding/json"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/client"
+	"github.com/aws/aws-sdk-go/aws/client/metadata"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// ProviderName is the name of the credentials provider.
+const ProviderName = `CredentialsEndpointProvider`
+
+// Provider satisfies the credentials.Provider interface, and is a client to
+// retrieve credentials from an arbitrary endpoint.
+type Provider struct {
+	staticCreds bool
+	credentials.Expiry
+
+	// Requires a AWS Client to make HTTP requests to the endpoint with.
+	// the Endpoint the request will be made to is provided by the aws.Config's
+	// Endpoint value.
+	Client *client.Client
+
+	// ExpiryWindow will allow the credentials to trigger refreshing prior to
+	// the credentials actually expiring. This is beneficial so race conditions
+	// with expiring credentials do not cause request to fail unexpectedly
+	// due to ExpiredTokenException exceptions.
+	//
+	// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
+	// 10 seconds before the credentials are actually expired.
+	//
+	// If ExpiryWindow is 0 or less it will be ignored.
+	ExpiryWindow time.Duration
+}
+
+// NewProviderClient returns a credentials Provider for retrieving AWS credentials
+// from arbitrary endpoint.
+func NewProviderClient(cfg aws.Config, handlers request.Handlers, endpoint string, options ...func(*Provider)) credentials.Provider {
+	p := &Provider{
+		Client: client.New(
+			cfg,
+			metadata.ClientInfo{
+				ServiceName: "CredentialsEndpoint",
+				Endpoint:    endpoint,
+			},
+			handlers,
+		),
+	}
+
+	p.Client.Handlers.Unmarshal.PushBack(unmarshalHandler)
+	p.Client.Handlers.UnmarshalError.PushBack(unmarshalError)
+	p.Client.Handlers.Validate.Clear()
+	p.Client.Handlers.Validate.PushBack(validateEndpointHandler)
+
+	for _, option := range options {
+		option(p)
+	}
+
+	return p
+}
+
+// NewCredentialsClient returns a Credentials wrapper for retrieving credentials
+// from an arbitrary endpoint concurrently. The client will request the
+func NewCredentialsClient(cfg aws.Config, handlers request.Handlers, endpoint string, options ...func(*Provider)) *credentials.Credentials {
+	return credentials.NewCredentials(NewProviderClient(cfg, handlers, endpoint, options...))
+}
+
+// IsExpired returns true if the credentials retrieved are expired, or not yet
+// retrieved.
+func (p *Provider) IsExpired() bool {
+	if p.staticCreds {
+		return false
+	}
+	return p.Expiry.IsExpired()
+}
+
+// Retrieve will attempt to request the credentials from the endpoint the Provider
+// was configured for. And error will be returned if the retrieval fails.
+func (p *Provider) Retrieve() (credentials.Value, error) {
+	resp, err := p.getCredentials()
+	if err != nil {
+		return credentials.Value{ProviderName: ProviderName},
+			awserr.New("CredentialsEndpointError", "failed to load credentials", err)
+	}
+
+	if resp.Expiration != nil {
+		p.SetExpiration(*resp.Expiration, p.ExpiryWindow)
+	} else {
+		p.staticCreds = true
+	}
+
+	return credentials.Value{
+		AccessKeyID:     resp.AccessKeyID,
+		SecretAccessKey: resp.SecretAccessKey,
+		SessionToken:    resp.Token,
+		ProviderName:    ProviderName,
+	}, nil
+}
+
+type getCredentialsOutput struct {
+	Expiration      *time.Time
+	AccessKeyID     string
+	SecretAccessKey string
+	Token           string
+}
+
+type errorOutput struct {
+	Code    string `json:"code"`
+	Message string `json:"message"`
+}
+
+func (p *Provider) getCredentials() (*getCredentialsOutput, error) {
+	op := &request.Operation{
+		Name:       "GetCredentials",
+		HTTPMethod: "GET",
+	}
+
+	out := &getCredentialsOutput{}
+	req := p.Client.NewRequest(op, nil, out)
+	req.HTTPRequest.Header.Set("Accept", "application/json")
+
+	return out, req.Send()
+}
+
+func validateEndpointHandler(r *request.Request) {
+	if len(r.ClientInfo.Endpoint) == 0 {
+		r.Error = aws.ErrMissingEndpoint
+	}
+}
+
+func unmarshalHandler(r *request.Request) {
+	defer r.HTTPResponse.Body.Close()
+
+	out := r.Data.(*getCredentialsOutput)
+	if err := json.NewDecoder(r.HTTPResponse.Body).Decode(&out); err != nil {
+		r.Error = awserr.New("SerializationError",
+			"failed to decode endpoint credentials",
+			err,
+		)
+	}
+}
+
+func unmarshalError(r *request.Request) {
+	defer r.HTTPResponse.Body.Close()
+
+	var errOut errorOutput
+	if err := json.NewDecoder(r.HTTPResponse.Body).Decode(&errOut); err != nil {
+		r.Error = awserr.New("SerializationError",
+			"failed to decode endpoint credentials",
+			err,
+		)
+	}
+
+	// Response body format is not consistent between metadata endpoints.
+	// Grab the error message as a string and include that as the source error
+	r.Error = awserr.New(errOut.Code, errOut.Message, nil)
+}
@@ -0,0 +1,78 @@
+package credentials
+
+import (
+	"os"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+// EnvProviderName provides a name of Env provider
+const EnvProviderName = "EnvProvider"
+
+var (
+	// ErrAccessKeyIDNotFound is returned when the AWS Access Key ID can't be
+	// found in the process's environment.
+	//
+	// @readonly
+	ErrAccessKeyIDNotFound = awserr.New("EnvAccessKeyNotFound", "AWS_ACCESS_KEY_ID or AWS_ACCESS_KEY not found in environment", nil)
+
+	// ErrSecretAccessKeyNotFound is returned when the AWS Secret Access Key
+	// can't be found in the process's environment.
+	//
+	// @readonly
+	ErrSecretAccessKeyNotFound = awserr.New("EnvSecretNotFound", "AWS_SECRET_ACCESS_KEY or AWS_SECRET_KEY not found in environment", nil)
+)
+
+// A EnvProvider retrieves credentials from the environment variables of the
+// running process. Environment credentials never expire.
+//
+// Environment variables used:
+//
+// * Access Key ID:     AWS_ACCESS_KEY_ID or AWS_ACCESS_KEY
+//
+// * Secret Access Key: AWS_SECRET_ACCESS_KEY or AWS_SECRET_KEY
+type EnvProvider struct {
+	retrieved bool
+}
+
+// NewEnvCredentials returns a pointer to a new Credentials object
+// wrapping the environment variable provider.
+func NewEnvCredentials() *Credentials {
+	return NewCredentials(&EnvProvider{})
+}
+
+// Retrieve retrieves the keys from the environment.
+func (e *EnvProvider) Retrieve() (Value, error) {
+	e.retrieved = false
+
+	id := os.Getenv("AWS_ACCESS_KEY_ID")
+	if id == "" {
+		id = os.Getenv("AWS_ACCESS_KEY")
+	}
+
+	secret := os.Getenv("AWS_SECRET_ACCESS_KEY")
+	if secret == "" {
+		secret = os.Getenv("AWS_SECRET_KEY")
+	}
+
+	if id == "" {
+		return Value{ProviderName: EnvProviderName}, ErrAccessKeyIDNotFound
+	}
+
+	if secret == "" {
+		return Value{ProviderName: EnvProviderName}, ErrSecretAccessKeyNotFound
+	}
+
+	e.retrieved = true
+	return Value{
+		AccessKeyID:     id,
+		SecretAccessKey: secret,
+		SessionToken:    os.Getenv("AWS_SESSION_TOKEN"),
+		ProviderName:    EnvProviderName,
+	}, nil
+}
+
+// IsExpired returns if the credentials have been retrieved.
+func (e *EnvProvider) IsExpired() bool {
+	return !e.retrieved
+}
@@ -0,0 +1,12 @@
+[default]
+aws_access_key_id = accessKey
+aws_secret_access_key = secret
+aws_session_token = token
+
+[no_token]
+aws_access_key_id = accessKey
+aws_secret_access_key = secret
+
+[with_colon]
+aws_access_key_id: accessKey
+aws_secret_access_key: secret
@@ -0,0 +1,150 @@
+package credentials
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/go-ini/ini"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/internal/shareddefaults"
+)
+
+// SharedCredsProviderName provides a name of SharedCreds provider
+const SharedCredsProviderName = "SharedCredentialsProvider"
+
+var (
+	// ErrSharedCredentialsHomeNotFound is emitted when the user directory cannot be found.
+	ErrSharedCredentialsHomeNotFound = awserr.New("UserHomeNotFound", "user home directory not found.", nil)
+)
+
+// A SharedCredentialsProvider retrieves credentials from the current user's home
+// directory, and keeps track if those credentials are expired.
+//
+// Profile ini file example: $HOME/.aws/credentials
+type SharedCredentialsProvider struct {
+	// Path to the shared credentials file.
+	//
+	// If empty will look for "AWS_SHARED_CREDENTIALS_FILE" env variable. If the
+	// env value is empty will default to current user's home directory.
+	// Linux/OSX: "$HOME/.aws/credentials"
+	// Windows:   "%USERPROFILE%\.aws\credentials"
+	Filename string
+
+	// AWS Profile to extract credentials from the shared credentials file. If empty
+	// will default to environment variable "AWS_PROFILE" or "default" if
+	// environment variable is also not set.
+	Profile string
+
+	// retrieved states if the credentials have been successfully retrieved.
+	retrieved bool
+}
+
+// NewSharedCredentials returns a pointer to a new Credentials object
+// wrapping the Profile file provider.
+func NewSharedCredentials(filename, profile string) *Credentials {
+	return NewCredentials(&SharedCredentialsProvider{
+		Filename: filename,
+		Profile:  profile,
+	})
+}
+
+// Retrieve reads and extracts the shared credentials from the current
+// users home directory.
+func (p *SharedCredentialsProvider) Retrieve() (Value, error) {
+	p.retrieved = false
+
+	filename, err := p.filename()
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, err
+	}
+
+	creds, err := loadProfile(filename, p.profile())
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, err
+	}
+
+	p.retrieved = true
+	return creds, nil
+}
+
+// IsExpired returns if the shared credentials have expired.
+func (p *SharedCredentialsProvider) IsExpired() bool {
+	return !p.retrieved
+}
+
+// loadProfiles loads from the file pointed to by shared credentials filename for profile.
+// The credentials retrieved from the profile will be returned or error. Error will be
+// returned if it fails to read from the file, or the data is invalid.
+func loadProfile(filename, profile string) (Value, error) {
+	config, err := ini.Load(filename)
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsLoad", "failed to load shared credentials file", err)
+	}
+	iniProfile, err := config.GetSection(profile)
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsLoad", "failed to get profile", err)
+	}
+
+	id, err := iniProfile.GetKey("aws_access_key_id")
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsAccessKey",
+			fmt.Sprintf("shared credentials %s in %s did not contain aws_access_key_id", profile, filename),
+			err)
+	}
+
+	secret, err := iniProfile.GetKey("aws_secret_access_key")
+	if err != nil {
+		return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsSecret",
+			fmt.Sprintf("shared credentials %s in %s did not contain aws_secret_access_key", profile, filename),
+			nil)
+	}
+
+	// Default to empty string if not found
+	token := iniProfile.Key("aws_session_token")
+
+	return Value{
+		AccessKeyID:     id.String(),
+		SecretAccessKey: secret.String(),
+		SessionToken:    token.String(),
+		ProviderName:    SharedCredsProviderName,
+	}, nil
+}
+
+// filename returns the filename to use to read AWS shared credentials.
+//
+// Will return an error if the user's home directory path cannot be found.
+func (p *SharedCredentialsProvider) filename() (string, error) {
+	if len(p.Filename) != 0 {
+		return p.Filename, nil
+	}
+
+	if p.Filename = os.Getenv("AWS_SHARED_CREDENTIALS_FILE"); len(p.Filename) != 0 {
+		return p.Filename, nil
+	}
+
+	if home := shareddefaults.UserHomeDir(); len(home) == 0 {
+		// Backwards compatibility of home directly not found error being returned.
+		// This error is too verbose, failure when opening the file would of been
+		// a better error to return.
+		return "", ErrSharedCredentialsHomeNotFound
+	}
+
+	p.Filename = shareddefaults.SharedCredentialsFilename()
+
+	return p.Filename, nil
+}
+
+// profile returns the AWS shared credentials profile.  If empty will read
+// environment variable "AWS_PROFILE". If that is not set profile will
+// return "default".
+func (p *SharedCredentialsProvider) profile() string {
+	if p.Profile == "" {
+		p.Profile = os.Getenv("AWS_PROFILE")
+	}
+	if p.Profile == "" {
+		p.Profile = "default"
+	}
+
+	return p.Profile
+}
@@ -0,0 +1,57 @@
+package credentials
+
+import (
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+// StaticProviderName provides a name of Static provider
+const StaticProviderName = "StaticProvider"
+
+var (
+	// ErrStaticCredentialsEmpty is emitted when static credentials are empty.
+	//
+	// @readonly
+	ErrStaticCredentialsEmpty = awserr.New("EmptyStaticCreds", "static credentials are empty", nil)
+)
+
+// A StaticProvider is a set of credentials which are set programmatically,
+// and will never expire.
+type StaticProvider struct {
+	Value
+}
+
+// NewStaticCredentials returns a pointer to a new Credentials object
+// wrapping a static credentials value provider.
+func NewStaticCredentials(id, secret, token string) *Credentials {
+	return NewCredentials(&StaticProvider{Value: Value{
+		AccessKeyID:     id,
+		SecretAccessKey: secret,
+		SessionToken:    token,
+	}})
+}
+
+// NewStaticCredentialsFromCreds returns a pointer to a new Credentials object
+// wrapping the static credentials value provide. Same as NewStaticCredentials
+// but takes the creds Value instead of individual fields
+func NewStaticCredentialsFromCreds(creds Value) *Credentials {
+	return NewCredentials(&StaticProvider{Value: creds})
+}
+
+// Retrieve returns the credentials or error if the credentials are invalid.
+func (s *StaticProvider) Retrieve() (Value, error) {
+	if s.AccessKeyID == "" || s.SecretAccessKey == "" {
+		return Value{ProviderName: StaticProviderName}, ErrStaticCredentialsEmpty
+	}
+
+	if len(s.Value.ProviderName) == 0 {
+		s.Value.ProviderName = StaticProviderName
+	}
+	return s.Value, nil
+}
+
+// IsExpired returns if the credentials are expired.
+//
+// For StaticProvider, the credentials never expired.
+func (s *StaticProvider) IsExpired() bool {
+	return false
+}
@@ -0,0 +1,298 @@
+/*
+Package stscreds are credential Providers to retrieve STS AWS credentials.
+
+STS provides multiple ways to retrieve credentials which can be used when making
+future AWS service API operation calls.
+
+The SDK will ensure that per instance of credentials.Credentials all requests
+to refresh the credentials will be synchronized. But, the SDK is unable to
+ensure synchronous usage of the AssumeRoleProvider if the value is shared
+between multiple Credentials, Sessions or service clients.
+
+Assume Role
+
+To assume an IAM role using STS with the SDK you can create a new Credentials
+with the SDKs's stscreds package.
+
+	// Initial credentials loaded from SDK's default credential chain. Such as
+	// the environment, shared credentials (~/.aws/credentials), or EC2 Instance
+	// Role. These credentials will be used to to make the STS Assume Role API.
+	sess := session.Must(session.NewSession())
+
+	// Create the credentials from AssumeRoleProvider to assume the role
+	// referenced by the "myRoleARN" ARN.
+	creds := stscreds.NewCredentials(sess, "myRoleArn")
+
+	// Create service client value configured for credentials
+	// from assumed role.
+	svc := s3.New(sess, &aws.Config{Credentials: creds})
+
+Assume Role with static MFA Token
+
+To assume an IAM role with a MFA token you can either specify a MFA token code
+directly or provide a function to prompt the user each time the credentials
+need to refresh the role's credentials. Specifying the TokenCode should be used
+for short lived operations that will not need to be refreshed, and when you do
+not want to have direct control over the user provides their MFA token.
+
+With TokenCode the AssumeRoleProvider will be not be able to refresh the role's
+credentials.
+
+	// Create the credentials from AssumeRoleProvider to assume the role
+	// referenced by the "myRoleARN" ARN using the MFA token code provided.
+	creds := stscreds.NewCredentials(sess, "myRoleArn", func(p *stscreds.AssumeRoleProvider) {
+		p.SerialNumber = aws.String("myTokenSerialNumber")
+		p.TokenCode = aws.String("00000000")
+	})
+
+	// Create service client value configured for credentials
+	// from assumed role.
+	svc := s3.New(sess, &aws.Config{Credentials: creds})
+
+Assume Role with MFA Token Provider
+
+To assume an IAM role with MFA for longer running tasks where the credentials
+may need to be refreshed setting the TokenProvider field of AssumeRoleProvider
+will allow the credential provider to prompt for new MFA token code when the
+role's credentials need to be refreshed.
+
+The StdinTokenProvider function is available to prompt on stdin to retrieve
+the MFA token code from the user. You can also implement custom prompts by
+satisfing the TokenProvider function signature.
+
+Using StdinTokenProvider with multiple AssumeRoleProviders, or Credentials will
+have undesirable results as the StdinTokenProvider will not be synchronized. A
+single Credentials with an AssumeRoleProvider can be shared safely.
+
+	// Create the credentials from AssumeRoleProvider to assume the role
+	// referenced by the "myRoleARN" ARN. Prompting for MFA token from stdin.
+	creds := stscreds.NewCredentials(sess, "myRoleArn", func(p *stscreds.AssumeRoleProvider) {
+		p.SerialNumber = aws.String("myTokenSerialNumber")
+		p.TokenProvider = stscreds.StdinTokenProvider
+	})
+
+	// Create service client value configured for credentials
+	// from assumed role.
+	svc := s3.New(sess, &aws.Config{Credentials: creds})
+
+*/
+package stscreds
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/client"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/service/sts"
+)
+
+// StdinTokenProvider will prompt on stdout and read from stdin for a string value.
+// An error is returned if reading from stdin fails.
+//
+// Use this function go read MFA tokens from stdin. The function makes no attempt
+// to make atomic prompts from stdin across multiple gorouties.
+//
+// Using StdinTokenProvider with multiple AssumeRoleProviders, or Credentials will
+// have undesirable results as the StdinTokenProvider will not be synchronized. A
+// single Credentials with an AssumeRoleProvider can be shared safely
+//
+// Will wait forever until something is provided on the stdin.
+func StdinTokenProvider() (string, error) {
+	var v string
+	fmt.Printf("Assume Role MFA token code: ")
+	_, err := fmt.Scanln(&v)
+
+	return v, err
+}
+
+// ProviderName provides a name of AssumeRole provider
+const ProviderName = "AssumeRoleProvider"
+
+// AssumeRoler represents the minimal subset of the STS client API used by this provider.
+type AssumeRoler interface {
+	AssumeRole(input *sts.AssumeRoleInput) (*sts.AssumeRoleOutput, error)
+}
+
+// DefaultDuration is the default amount of time in minutes that the credentials
+// will be valid for.
+var DefaultDuration = time.Duration(15) * time.Minute
+
+// AssumeRoleProvider retrieves temporary credentials from the STS service, and
+// keeps track of their expiration time.
+//
+// This credential provider will be used by the SDKs default credential change
+// when shared configuration is enabled, and the shared config or shared credentials
+// file configure assume role. See Session docs for how to do this.
+//
+// AssumeRoleProvider does not provide any synchronization and it is not safe
+// to share this value across multiple Credentials, Sessions, or service clients
+// without also sharing the same Credentials instance.
+type AssumeRoleProvider struct {
+	credentials.Expiry
+
+	// STS client to make assume role request with.
+	Client AssumeRoler
+
+	// Role to be assumed.
+	RoleARN string
+
+	// Session name, if you wish to reuse the credentials elsewhere.
+	RoleSessionName string
+
+	// Expiry duration of the STS credentials. Defaults to 15 minutes if not set.
+	Duration time.Duration
+
+	// Optional ExternalID to pass along, defaults to nil if not set.
+	ExternalID *string
+
+	// The policy plain text must be 2048 bytes or shorter. However, an internal
+	// conversion compresses it into a packed binary format with a separate limit.
+	// The PackedPolicySize response element indicates by percentage how close to
+	// the upper size limit the policy is, with 100% equaling the maximum allowed
+	// size.
+	Policy *string
+
+	// The identification number of the MFA device that is associated with the user
+	// who is making the AssumeRole call. Specify this value if the trust policy
+	// of the role being assumed includes a condition that requires MFA authentication.
+	// The value is either the serial number for a hardware device (such as GAHT12345678)
+	// or an Amazon Resource Name (ARN) for a virtual device (such as arn:aws:iam::123456789012:mfa/user).
+	SerialNumber *string
+
+	// The value provided by the MFA device, if the trust policy of the role being
+	// assumed requires MFA (that is, if the policy includes a condition that tests
+	// for MFA). If the role being assumed requires MFA and if the TokenCode value
+	// is missing or expired, the AssumeRole call returns an "access denied" error.
+	//
+	// If SerialNumber is set and neither TokenCode nor TokenProvider are also
+	// set an error will be returned.
+	TokenCode *string
+
+	// Async method of providing MFA token code for assuming an IAM role with MFA.
+	// The value returned by the function will be used as the TokenCode in the Retrieve
+	// call. See StdinTokenProvider for a provider that prompts and reads from stdin.
+	//
+	// This token provider will be called when ever the assumed role's
+	// credentials need to be refreshed when SerialNumber is also set and
+	// TokenCode is not set.
+	//
+	// If both TokenCode and TokenProvider is set, TokenProvider will be used and
+	// TokenCode is ignored.
+	TokenProvider func() (string, error)
+
+	// ExpiryWindow will allow the credentials to trigger refreshing prior to
+	// the credentials actually expiring. This is beneficial so race conditions
+	// with expiring credentials do not cause request to fail unexpectedly
+	// due to ExpiredTokenException exceptions.
+	//
+	// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
+	// 10 seconds before the credentials are actually expired.
+	//
+	// If ExpiryWindow is 0 or less it will be ignored.
+	ExpiryWindow time.Duration
+}
+
+// NewCredentials returns a pointer to a new Credentials object wrapping the
+// AssumeRoleProvider. The credentials will expire every 15 minutes and the
+// role will be named after a nanosecond timestamp of this operation.
+//
+// Takes a Config provider to create the STS client. The ConfigProvider is
+// satisfied by the session.Session type.
+//
+// It is safe to share the returned Credentials with multiple Sessions and
+// service clients. All access to the credentials and refreshing them
+// will be synchronized.
+func NewCredentials(c client.ConfigProvider, roleARN string, options ...func(*AssumeRoleProvider)) *credentials.Credentials {
+	p := &AssumeRoleProvider{
+		Client:   sts.New(c),
+		RoleARN:  roleARN,
+		Duration: DefaultDuration,
+	}
+
+	for _, option := range options {
+		option(p)
+	}
+
+	return credentials.NewCredentials(p)
+}
+
+// NewCredentialsWithClient returns a pointer to a new Credentials object wrapping the
+// AssumeRoleProvider. The credentials will expire every 15 minutes and the
+// role will be named after a nanosecond timestamp of this operation.
+//
+// Takes an AssumeRoler which can be satisfied by the STS client.
+//
+// It is safe to share the returned Credentials with multiple Sessions and
+// service clients. All access to the credentials and refreshing them
+// will be synchronized.
+func NewCredentialsWithClient(svc AssumeRoler, roleARN string, options ...func(*AssumeRoleProvider)) *credentials.Credentials {
+	p := &AssumeRoleProvider{
+		Client:   svc,
+		RoleARN:  roleARN,
+		Duration: DefaultDuration,
+	}
+
+	for _, option := range options {
+		option(p)
+	}
+
+	return credentials.NewCredentials(p)
+}
+
+// Retrieve generates a new set of temporary credentials using STS.
+func (p *AssumeRoleProvider) Retrieve() (credentials.Value, error) {
+
+	// Apply defaults where parameters are not set.
+	if p.RoleSessionName == "" {
+		// Try to work out a role name that will hopefully end up unique.
+		p.RoleSessionName = fmt.Sprintf("%d", time.Now().UTC().UnixNano())
+	}
+	if p.Duration == 0 {
+		// Expire as often as AWS permits.
+		p.Duration = DefaultDuration
+	}
+	input := &sts.AssumeRoleInput{
+		DurationSeconds: aws.Int64(int64(p.Duration / time.Second)),
+		RoleArn:         aws.String(p.RoleARN),
+		RoleSessionName: aws.String(p.RoleSessionName),
+		ExternalId:      p.ExternalID,
+	}
+	if p.Policy != nil {
+		input.Policy = p.Policy
+	}
+	if p.SerialNumber != nil {
+		if p.TokenCode != nil {
+			input.SerialNumber = p.SerialNumber
+			input.TokenCode = p.TokenCode
+		} else if p.TokenProvider != nil {
+			input.SerialNumber = p.SerialNumber
+			code, err := p.TokenProvider()
+			if err != nil {
+				return credentials.Value{ProviderName: ProviderName}, err
+			}
+			input.TokenCode = aws.String(code)
+		} else {
+			return credentials.Value{ProviderName: ProviderName},
+				awserr.New("AssumeRoleTokenNotAvailable",
+					"assume role with MFA enabled, but neither TokenCode nor TokenProvider are set", nil)
+		}
+	}
+
+	roleOutput, err := p.Client.AssumeRole(input)
+	if err != nil {
+		return credentials.Value{ProviderName: ProviderName}, err
+	}
+
+	// We will proactively generate new credentials before they expire.
+	p.SetExpiration(*roleOutput.Credentials.Expiration, p.ExpiryWindow)
+
+	return credentials.Value{
+		AccessKeyID:     *roleOutput.Credentials.AccessKeyId,
+		SecretAccessKey: *roleOutput.Credentials.SecretAccessKey,
+		SessionToken:    *roleOutput.Credentials.SessionToken,
+		ProviderName:    ProviderName,
+	}, nil
+}
@@ -0,0 +1,194 @@
+// Package defaults is a collection of helpers to retrieve the SDK's default
+// configuration and handlers.
+//
+// Generally this package shouldn't be used directly, but session.Session
+// instead. This package is useful when you need to reset the defaults
+// of a session or service client to the SDK defaults before setting
+// additional parameters.
+package defaults
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/corehandlers"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
+	"github.com/aws/aws-sdk-go/aws/credentials/endpointcreds"
+	"github.com/aws/aws-sdk-go/aws/ec2metadata"
+	"github.com/aws/aws-sdk-go/aws/endpoints"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// A Defaults provides a collection of default values for SDK clients.
+type Defaults struct {
+	Config   *aws.Config
+	Handlers request.Handlers
+}
+
+// Get returns the SDK's default values with Config and handlers pre-configured.
+func Get() Defaults {
+	cfg := Config()
+	handlers := Handlers()
+	cfg.Credentials = CredChain(cfg, handlers)
+
+	return Defaults{
+		Config:   cfg,
+		Handlers: handlers,
+	}
+}
+
+// Config returns the default configuration without credentials.
+// To retrieve a config with credentials also included use
+// `defaults.Get().Config` instead.
+//
+// Generally you shouldn't need to use this method directly, but
+// is available if you need to reset the configuration of an
+// existing service client or session.
+func Config() *aws.Config {
+	return aws.NewConfig().
+		WithCredentials(credentials.AnonymousCredentials).
+		WithRegion(os.Getenv("AWS_REGION")).
+		WithHTTPClient(http.DefaultClient).
+		WithMaxRetries(aws.UseServiceDefaultRetries).
+		WithLogger(aws.NewDefaultLogger()).
+		WithLogLevel(aws.LogOff).
+		WithEndpointResolver(endpoints.DefaultResolver())
+}
+
+// Handlers returns the default request handlers.
+//
+// Generally you shouldn't need to use this method directly, but
+// is available if you need to reset the request handlers of an
+// existing service client or session.
+func Handlers() request.Handlers {
+	var handlers request.Handlers
+
+	handlers.Validate.PushBackNamed(corehandlers.ValidateEndpointHandler)
+	handlers.Validate.AfterEachFn = request.HandlerListStopOnError
+	handlers.Build.PushBackNamed(corehandlers.SDKVersionUserAgentHandler)
+	handlers.Build.PushBackNamed(corehandlers.AddHostExecEnvUserAgentHander)
+	handlers.Build.AfterEachFn = request.HandlerListStopOnError
+	handlers.Sign.PushBackNamed(corehandlers.BuildContentLengthHandler)
+	handlers.Send.PushBackNamed(corehandlers.ValidateReqSigHandler)
+	handlers.Send.PushBackNamed(corehandlers.SendHandler)
+	handlers.AfterRetry.PushBackNamed(corehandlers.AfterRetryHandler)
+	handlers.ValidateResponse.PushBackNamed(corehandlers.ValidateResponseHandler)
+
+	return handlers
+}
+
+// CredChain returns the default credential chain.
+//
+// Generally you shouldn't need to use this method directly, but
+// is available if you need to reset the credentials of an
+// existing service client or session's Config.
+func CredChain(cfg *aws.Config, handlers request.Handlers) *credentials.Credentials {
+	return credentials.NewCredentials(&credentials.ChainProvider{
+		VerboseErrors: aws.BoolValue(cfg.CredentialsChainVerboseErrors),
+		Providers: []credentials.Provider{
+			&credentials.EnvProvider{},
+			&credentials.SharedCredentialsProvider{Filename: "", Profile: ""},
+			RemoteCredProvider(*cfg, handlers),
+		},
+	})
+}
+
+const (
+	httpProviderEnvVar     = "AWS_CONTAINER_CREDENTIALS_FULL_URI"
+	ecsCredsProviderEnvVar = "AWS_CONTAINER_CREDENTIALS_RELATIVE_URI"
+)
+
+// RemoteCredProvider returns a credentials provider for the default remote
+// endpoints such as EC2 or ECS Roles.
+func RemoteCredProvider(cfg aws.Config, handlers request.Handlers) credentials.Provider {
+	if u := os.Getenv(httpProviderEnvVar); len(u) > 0 {
+		return localHTTPCredProvider(cfg, handlers, u)
+	}
+
+	if uri := os.Getenv(ecsCredsProviderEnvVar); len(uri) > 0 {
+		u := fmt.Sprintf("http://169.254.170.2%s", uri)
+		return httpCredProvider(cfg, handlers, u)
+	}
+
+	return ec2RoleProvider(cfg, handlers)
+}
+
+var lookupHostFn = net.LookupHost
+
+func isLoopbackHost(host string) (bool, error) {
+	ip := net.ParseIP(host)
+	if ip != nil {
+		return ip.IsLoopback(), nil
+	}
+
+	// Host is not an ip, perform lookup
+	addrs, err := lookupHostFn(host)
+	if err != nil {
+		return false, err
+	}
+	for _, addr := range addrs {
+		if !net.ParseIP(addr).IsLoopback() {
+			return false, nil
+		}
+	}
+
+	return true, nil
+}
+
+func localHTTPCredProvider(cfg aws.Config, handlers request.Handlers, u string) credentials.Provider {
+	var errMsg string
+
+	parsed, err := url.Parse(u)
+	if err != nil {
+		errMsg = fmt.Sprintf("invalid URL, %v", err)
+	} else {
+		host := aws.URLHostname(parsed)
+		if len(host) == 0 {
+			errMsg = "unable to parse host from local HTTP cred provider URL"
+		} else if isLoopback, loopbackErr := isLoopbackHost(host); loopbackErr != nil {
+			errMsg = fmt.Sprintf("failed to resolve host %q, %v", host, loopbackErr)
+		} else if !isLoopback {
+			errMsg = fmt.Sprintf("invalid endpoint host, %q, only loopback hosts are allowed.", host)
+		}
+	}
+
+	if len(errMsg) > 0 {
+		if cfg.Logger != nil {
+			cfg.Logger.Log("Ignoring, HTTP credential provider", errMsg, err)
+		}
+		return credentials.ErrorProvider{
+			Err:          awserr.New("CredentialsEndpointError", errMsg, err),
+			ProviderName: endpointcreds.ProviderName,
+		}
+	}
+
+	return httpCredProvider(cfg, handlers, u)
+}
+
+func httpCredProvider(cfg aws.Config, handlers request.Handlers, u string) credentials.Provider {
+	return endpointcreds.NewProviderClient(cfg, handlers, u,
+		func(p *endpointcreds.Provider) {
+			p.ExpiryWindow = 5 * time.Minute
+		},
+	)
+}
+
+func ec2RoleProvider(cfg aws.Config, handlers request.Handlers) credentials.Provider {
+	resolver := cfg.EndpointResolver
+	if resolver == nil {
+		resolver = endpoints.DefaultResolver()
+	}
+
+	e, _ := resolver.EndpointFor(endpoints.Ec2metadataServiceID, "")
+	return &ec2rolecreds.EC2RoleProvider{
+		Client:       ec2metadata.NewClient(cfg, handlers, e.URL, e.SigningRegion),
+		ExpiryWindow: 5 * time.Minute,
+	}
+}
@@ -0,0 +1,27 @@
+package defaults
+
+import (
+	"github.com/aws/aws-sdk-go/internal/shareddefaults"
+)
+
+// SharedCredentialsFilename returns the SDK's default file path
+// for the shared credentials file.
+//
+// Builds the shared config file path based on the OS's platform.
+//
+//   - Linux/Unix: $HOME/.aws/credentials
+//   - Windows: %USERPROFILE%\.aws\credentials
+func SharedCredentialsFilename() string {
+	return shareddefaults.SharedCredentialsFilename()
+}
+
+// SharedConfigFilename returns the SDK's default file path for
+// the shared config file.
+//
+// Builds the shared config file path based on the OS's platform.
+//
+//   - Linux/Unix: $HOME/.aws/config
+//   - Windows: %USERPROFILE%\.aws\config
+func SharedConfigFilename() string {
+	return shareddefaults.SharedConfigFilename()
+}
@@ -0,0 +1,56 @@
+// Package aws provides the core SDK's utilities and shared types. Use this package's
+// utilities to simplify setting and reading API operations parameters.
+//
+// Value and Pointer Conversion Utilities
+//
+// This package includes a helper conversion utility for each scalar type the SDK's
+// API use. These utilities make getting a pointer of the scalar, and dereferencing
+// a pointer easier.
+//
+// Each conversion utility comes in two forms. Value to Pointer and Pointer to Value.
+// The Pointer to value will safely dereference the pointer and return its value.
+// If the pointer was nil, the scalar's zero value will be returned.
+//
+// The value to pointer functions will be named after the scalar type. So get a
+// *string from a string value use the "String" function. This makes it easy to
+// to get pointer of a literal string value, because getting the address of a
+// literal requires assigning the value to a variable first.
+//
+//    var strPtr *string
+//
+//    // Without the SDK's conversion functions
+//    str := "my string"
+//    strPtr = &str
+//
+//    // With the SDK's conversion functions
+//    strPtr = aws.String("my string")
+//
+//    // Convert *string to string value
+//    str = aws.StringValue(strPtr)
+//
+// In addition to scalars the aws package also includes conversion utilities for
+// map and slice for commonly types used in API parameters. The map and slice
+// conversion functions use similar naming pattern as the scalar conversion
+// functions.
+//
+//    var strPtrs []*string
+//    var strs []string = []string{"Go", "Gophers", "Go"}
+//
+//    // Convert []string to []*string
+//    strPtrs = aws.StringSlice(strs)
+//
+//    // Convert []*string to []string
+//    strs = aws.StringValueSlice(strPtrs)
+//
+// SDK Default HTTP Client
+//
+// The SDK will use the http.DefaultClient if a HTTP client is not provided to
+// the SDK's Session, or service client constructor. This means that if the
+// http.DefaultClient is modified by other components of your application the
+// modifications will be picked up by the SDK as well.
+//
+// In some cases this might be intended, but it is a better practice to create
+// a custom HTTP Client to share explicitly through your application. You can
+// configure the SDK to use the custom HTTP Client by setting the HTTPClient
+// value of the SDK's Config type when creating a Session or service client.
+package aws
@@ -0,0 +1,162 @@
+package ec2metadata
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"path"
+	"strings"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// GetMetadata uses the path provided to request information from the EC2
+// instance metdata service. The content will be returned as a string, or
+// error if the request failed.
+func (c *EC2Metadata) GetMetadata(p string) (string, error) {
+	op := &request.Operation{
+		Name:       "GetMetadata",
+		HTTPMethod: "GET",
+		HTTPPath:   path.Join("/", "meta-data", p),
+	}
+
+	output := &metadataOutput{}
+	req := c.NewRequest(op, nil, output)
+
+	return output.Content, req.Send()
+}
+
+// GetUserData returns the userdata that was configured for the service. If
+// there is no user-data setup for the EC2 instance a "NotFoundError" error
+// code will be returned.
+func (c *EC2Metadata) GetUserData() (string, error) {
+	op := &request.Operation{
+		Name:       "GetUserData",
+		HTTPMethod: "GET",
+		HTTPPath:   path.Join("/", "user-data"),
+	}
+
+	output := &metadataOutput{}
+	req := c.NewRequest(op, nil, output)
+	req.Handlers.UnmarshalError.PushBack(func(r *request.Request) {
+		if r.HTTPResponse.StatusCode == http.StatusNotFound {
+			r.Error = awserr.New("NotFoundError", "user-data not found", r.Error)
+		}
+	})
+
+	return output.Content, req.Send()
+}
+
+// GetDynamicData uses the path provided to request information from the EC2
+// instance metadata service for dynamic data. The content will be returned
+// as a string, or error if the request failed.
+func (c *EC2Metadata) GetDynamicData(p string) (string, error) {
+	op := &request.Operation{
+		Name:       "GetDynamicData",
+		HTTPMethod: "GET",
+		HTTPPath:   path.Join("/", "dynamic", p),
+	}
+
+	output := &metadataOutput{}
+	req := c.NewRequest(op, nil, output)
+
+	return output.Content, req.Send()
+}
+
+// GetInstanceIdentityDocument retrieves an identity document describing an
+// instance. Error is returned if the request fails or is unable to parse
+// the response.
+func (c *EC2Metadata) GetInstanceIdentityDocument() (EC2InstanceIdentityDocument, error) {
+	resp, err := c.GetDynamicData("instance-identity/document")
+	if err != nil {
+		return EC2InstanceIdentityDocument{},
+			awserr.New("EC2MetadataRequestError",
+				"failed to get EC2 instance identity document", err)
+	}
+
+	doc := EC2InstanceIdentityDocument{}
+	if err := json.NewDecoder(strings.NewReader(resp)).Decode(&doc); err != nil {
+		return EC2InstanceIdentityDocument{},
+			awserr.New("SerializationError",
+				"failed to decode EC2 instance identity document", err)
+	}
+
+	return doc, nil
+}
+
+// IAMInfo retrieves IAM info from the metadata API
+func (c *EC2Metadata) IAMInfo() (EC2IAMInfo, error) {
+	resp, err := c.GetMetadata("iam/info")
+	if err != nil {
+		return EC2IAMInfo{},
+			awserr.New("EC2MetadataRequestError",
+				"failed to get EC2 IAM info", err)
+	}
+
+	info := EC2IAMInfo{}
+	if err := json.NewDecoder(strings.NewReader(resp)).Decode(&info); err != nil {
+		return EC2IAMInfo{},
+			awserr.New("SerializationError",
+				"failed to decode EC2 IAM info", err)
+	}
+
+	if info.Code != "Success" {
+		errMsg := fmt.Sprintf("failed to get EC2 IAM Info (%s)", info.Code)
+		return EC2IAMInfo{},
+			awserr.New("EC2MetadataError", errMsg, nil)
+	}
+
+	return info, nil
+}
+
+// Region returns the region the instance is running in.
+func (c *EC2Metadata) Region() (string, error) {
+	resp, err := c.GetMetadata("placement/availability-zone")
+	if err != nil {
+		return "", err
+	}
+
+	// returns region without the suffix. Eg: us-west-2a becomes us-west-2
+	return resp[:len(resp)-1], nil
+}
+
+// Available returns if the application has access to the EC2 Metadata service.
+// Can be used to determine if application is running within an EC2 Instance and
+// the metadata service is available.
+func (c *EC2Metadata) Available() bool {
+	if _, err := c.GetMetadata("instance-id"); err != nil {
+		return false
+	}
+
+	return true
+}
+
+// An EC2IAMInfo provides the shape for unmarshaling
+// an IAM info from the metadata API
+type EC2IAMInfo struct {
+	Code               string
+	LastUpdated        time.Time
+	InstanceProfileArn string
+	InstanceProfileID  string
+}
+
+// An EC2InstanceIdentityDocument provides the shape for unmarshaling
+// an instance identity document
+type EC2InstanceIdentityDocument struct {
+	DevpayProductCodes []string  `json:"devpayProductCodes"`
+	AvailabilityZone   string    `json:"availabilityZone"`
+	PrivateIP          string    `json:"privateIp"`
+	Version            string    `json:"version"`
+	Region             string    `json:"region"`
+	InstanceID         string    `json:"instanceId"`
+	BillingProducts    []string  `json:"billingProducts"`
+	InstanceType       string    `json:"instanceType"`
+	AccountID          string    `json:"accountId"`
+	PendingTime        time.Time `json:"pendingTime"`
+	ImageID            string    `json:"imageId"`
+	KernelID           string    `json:"kernelId"`
+	RamdiskID          string    `json:"ramdiskId"`
+	Architecture       string    `json:"architecture"`
+}
@@ -0,0 +1,148 @@
+// Package ec2metadata provides the client for making API calls to the
+// EC2 Metadata service.
+//
+// This package's client can be disabled completely by setting the environment
+// variable "AWS_EC2_METADATA_DISABLED=true". This environment variable set to
+// true instructs the SDK to disable the EC2 Metadata client. The client cannot
+// be used while the environemnt variable is set to true, (case insensitive).
+package ec2metadata
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/awserr"
+	"github.com/aws/aws-sdk-go/aws/client"
+	"github.com/aws/aws-sdk-go/aws/client/metadata"
+	"github.com/aws/aws-sdk-go/aws/corehandlers"
+	"github.com/aws/aws-sdk-go/aws/request"
+)
+
+// ServiceName is the name of the service.
+const ServiceName = "ec2metadata"
+const disableServiceEnvVar = "AWS_EC2_METADATA_DISABLED"
+
+// A EC2Metadata is an EC2 Metadata service Client.
+type EC2Metadata struct {
+	*client.Client
+}
+
+// New creates a new instance of the EC2Metadata client with a session.
+// This client is safe to use across multiple goroutines.
+//
+//
+// Example:
+//     // Create a EC2Metadata client from just a session.
+//     svc := ec2metadata.New(mySession)
+//
+//     // Create a EC2Metadata client with additional configuration
+//     svc := ec2metadata.New(mySession, aws.NewConfig().WithLogLevel(aws.LogDebugHTTPBody))
+func New(p client.ConfigProvider, cfgs ...*aws.Config) *EC2Metadata {
+	c := p.ClientConfig(ServiceName, cfgs...)
+	return NewClient(*c.Config, c.Handlers, c.Endpoint, c.SigningRegion)
+}
+
+// NewClient returns a new EC2Metadata client. Should be used to create
+// a client when not using a session. Generally using just New with a session
+// is preferred.
+//
+// If an unmodified HTTP client is provided from the stdlib default, or no client
+// the EC2RoleProvider's EC2Metadata HTTP client's timeout will be shortened.
+// To disable this set Config.EC2MetadataDisableTimeoutOverride to false. Enabled by default.
+func NewClient(cfg aws.Config, handlers request.Handlers, endpoint, signingRegion string, opts ...func(*client.Client)) *EC2Metadata {
+	if !aws.BoolValue(cfg.EC2MetadataDisableTimeoutOverride) && httpClientZero(cfg.HTTPClient) {
+		// If the http client is unmodified and this feature is not disabled
+		// set custom timeouts for EC2Metadata requests.
+		cfg.HTTPClient = &http.Client{
+			// use a shorter timeout than default because the metadata
+			// service is local if it is running, and to fail faster
+			// if not running on an ec2 instance.
+			Timeout: 5 * time.Second,
+		}
+	}
+
+	svc := &EC2Metadata{
+		Client: client.New(
+			cfg,
+			metadata.ClientInfo{
+				ServiceName: ServiceName,
+				Endpoint:    endpoint,
+				APIVersion:  "latest",
+			},
+			handlers,
+		),
+	}
+
+	svc.Handlers.Unmarshal.PushBack(unmarshalHandler)
+	svc.Handlers.UnmarshalError.PushBack(unmarshalError)
+	svc.Handlers.Validate.Clear()
+	svc.Handlers.Validate.PushBack(validateEndpointHandler)
+
+	// Disable the EC2 Metadata service if the environment variable is set.
+	// This shortcirctes the service's functionality to always fail to send
+	// requests.
+	if strings.ToLower(os.Getenv(disableServiceEnvVar)) == "true" {
+		svc.Handlers.Send.SwapNamed(request.NamedHandler{
+			Name: corehandlers.SendHandler.Name,
+			Fn: func(r *request.Request) {
+				r.Error = awserr.New(
+					request.CanceledErrorCode,
+					"EC2 IMDS access disabled via "+disableServiceEnvVar+" env var",
+					nil)
+			},
+		})
+	}
+
+	// Add additional options to the service config
+	for _, option := range opts {
+		option(svc.Client)
+	}
+
+	return svc
+}
+
+func httpClientZero(c *http.Client) bool {
+	return c == nil || (c.Transport == nil && c.CheckRedirect == nil && c.Jar == nil && c.Timeout == 0)
+}
+
+type metadataOutput struct {
+	Content string
+}
+
+func unmarshalHandler(r *request.Request) {
+	defer r.HTTPResponse.Body.Close()
+	b := &bytes.Buffer{}
+	if _, err := io.Copy(b, r.HTTPResponse.Body); err != nil {
+		r.Error = awserr.New("SerializationError", "unable to unmarshal EC2 metadata respose", err)
+		return
+	}
+
+	if data, ok := r.Data.(*metadataOutput); ok {
+		data.Content = b.String()
+	}
+}
+
+func unmarshalError(r *request.Request) {
+	defer r.HTTPResponse.Body.Close()
+	b := &bytes.Buffer{}
+	if _, err := io.Copy(b, r.HTTPResponse.Body); err != nil {
+		r.Error = awserr.New("SerializationError", "unable to unmarshal EC2 metadata error respose", err)
+		return
+	}
+
+	// Response body format is not consistent between metadata endpoints.
+	// Grab the error message as a string and include that as the source error
+	r.Error = awserr.New("EC2MetadataError", "failed to make EC2Metadata request", errors.New(b.String()))
+}
+
+func validateEndpointHandler(r *request.Request) {
+	if r.ClientInfo.Endpoint == "" {
+		r.Error = aws.ErrMissingEndpoint
+	}
+}
@@ -0,0 +1,133 @@
+package endpoints
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+type modelDefinition map[string]json.RawMessage
+
+// A DecodeModelOptions are the options for how the endpoints model definition
+// are decoded.
+type DecodeModelOptions struct {
+	SkipCustomizations bool
+}
+
+// Set combines all of the option functions together.
+func (d *DecodeModelOptions) Set(optFns ...func(*DecodeModelOptions)) {
+	for _, fn := range optFns {
+		fn(d)
+	}
+}
+
+// DecodeModel unmarshals a Regions and Endpoint model definition file into
+// a endpoint Resolver. If the file format is not supported, or an error occurs
+// when unmarshaling the model an error will be returned.
+//
+// Casting the return value of this func to a EnumPartitions will
+// allow you to get a list of the partitions in the order the endpoints
+// will be resolved in.
+//
+//    resolver, err := endpoints.DecodeModel(reader)
+//
+//    partitions := resolver.(endpoints.EnumPartitions).Partitions()
+//    for _, p := range partitions {
+//        // ... inspect partitions
+//    }
+func DecodeModel(r io.Reader, optFns ...func(*DecodeModelOptions)) (Resolver, error) {
+	var opts DecodeModelOptions
+	opts.Set(optFns...)
+
+	// Get the version of the partition file to determine what
+	// unmarshaling model to use.
+	modelDef := modelDefinition{}
+	if err := json.NewDecoder(r).Decode(&modelDef); err != nil {
+		return nil, newDecodeModelError("failed to decode endpoints model", err)
+	}
+
+	var version string
+	if b, ok := modelDef["version"]; ok {
+		version = string(b)
+	} else {
+		return nil, newDecodeModelError("endpoints version not found in model", nil)
+	}
+
+	if version == "3" {
+		return decodeV3Endpoints(modelDef, opts)
+	}
+
+	return nil, newDecodeModelError(
+		fmt.Sprintf("endpoints version %s, not supported", version), nil)
+}
+
+func decodeV3Endpoints(modelDef modelDefinition, opts DecodeModelOptions) (Resolver, error) {
+	b, ok := modelDef["partitions"]
+	if !ok {
+		return nil, newDecodeModelError("endpoints model missing partitions", nil)
+	}
+
+	ps := partitions{}
+	if err := json.Unmarshal(b, &ps); err != nil {
+		return nil, newDecodeModelError("failed to decode endpoints model", err)
+	}
+
+	if opts.SkipCustomizations {
+		return ps, nil
+	}
+
+	// Customization
+	for i := 0; i < len(ps); i++ {
+		p := &ps[i]
+		custAddEC2Metadata(p)
+		custAddS3DualStack(p)
+		custRmIotDataService(p)
+	}
+
+	return ps, nil
+}
+
+func custAddS3DualStack(p *partition) {
+	if p.ID != "aws" {
+		return
+	}
+
+	s, ok := p.Services["s3"]
+	if !ok {
+		return
+	}
+
+	s.Defaults.HasDualStack = boxedTrue
+	s.Defaults.DualStackHostname = "{service}.dualstack.{region}.{dnsSuffix}"
+
+	p.Services["s3"] = s
+}
+
+func custAddEC2Metadata(p *partition) {
+	p.Services["ec2metadata"] = service{
+		IsRegionalized:    boxedFalse,
+		PartitionEndpoint: "aws-global",
+		Endpoints: endpoints{
+			"aws-global": endpoint{
+				Hostname:  "169.254.169.254/latest",
+				Protocols: []string{"http"},
+			},
+		},
+	}
+}
+
+func custRmIotDataService(p *partition) {
+	delete(p.Services, "data.iot")
+}
+
+type decodeModelError struct {
+	awsError
+}
+
+func newDecodeModelError(msg string, err error) decodeModelError {
+	return decodeModelError{
+		awsError: awserr.New("DecodeEndpointsModelError", msg, err),
+	}
+}
@@ -0,0 +1,66 @@
+// Package endpoints provides the types and functionality for defining regions
+// and endpoints, as well as querying those definitions.
+//
+// The SDK's Regions and Endpoints metadata is code generated into the endpoints
+// package, and is accessible via the DefaultResolver function. This function
+// returns a endpoint Resolver will search the metadata and build an associated
+// endpoint if one is found. The default resolver will search all partitions
+// known by the SDK. e.g AWS Standard (aws), AWS China (aws-cn), and
+// AWS GovCloud (US) (aws-us-gov).
+// .
+//
+// Enumerating Regions and Endpoint Metadata
+//
+// Casting the Resolver returned by DefaultResolver to a EnumPartitions interface
+// will allow you to get access to the list of underlying Partitions with the
+// Partitions method. This is helpful if you want to limit the SDK's endpoint
+// resolving to a single partition, or enumerate regions, services, and endpoints
+// in the partition.
+//
+//     resolver := endpoints.DefaultResolver()
+//     partitions := resolver.(endpoints.EnumPartitions).Partitions()
+//
+//     for _, p := range partitions {
+//         fmt.Println("Regions for", p.ID())
+//         for id, _ := range p.Regions() {
+//             fmt.Println("*", id)
+//         }
+//
+//         fmt.Println("Services for", p.ID())
+//         for id, _ := range p.Services() {
+//             fmt.Println("*", id)
+//         }
+//     }
+//
+// Using Custom Endpoints
+//
+// The endpoints package also gives you the ability to use your own logic how
+// endpoints are resolved. This is a great way to define a custom endpoint
+// for select services, without passing that logic down through your code.
+//
+// If a type implements the Resolver interface it can be used to resolve
+// endpoints. To use this with the SDK's Session and Config set the value
+// of the type to the EndpointsResolver field of aws.Config when initializing
+// the session, or service client.
+//
+// In addition the ResolverFunc is a wrapper for a func matching the signature
+// of Resolver.EndpointFor, converting it to a type that satisfies the
+// Resolver interface.
+//
+//
+//     myCustomResolver := func(service, region string, optFns ...func(*endpoints.Options)) (endpoints.ResolvedEndpoint, error) {
+//         if service == endpoints.S3ServiceID {
+//             return endpoints.ResolvedEndpoint{
+//                 URL:           "s3.custom.endpoint.com",
+//                 SigningRegion: "custom-signing-region",
+//             }, nil
+//         }
+//
+//         return endpoints.DefaultResolver().EndpointFor(service, region, optFns...)
+//     }
+//
+//     sess := session.Must(session.NewSession(&aws.Config{
+//         Region:           aws.String("us-west-2"),
+//         EndpointResolver: endpoints.ResolverFunc(myCustomResolver),
+//     }))
+package endpoints
@@ -0,0 +1,443 @@
+package endpoints
+
+import (
+	"fmt"
+	"regexp"
+
+	"github.com/aws/aws-sdk-go/aws/awserr"
+)
+
+// Options provide the configuration needed to direct how the
+// endpoints will be resolved.
+type Options struct {
+	// DisableSSL forces the endpoint to be resolved as HTTP.
+	// instead of HTTPS if the service supports it.
+	DisableSSL bool
+
+	// Sets the resolver to resolve the endpoint as a dualstack endpoint
+	// for the service. If dualstack support for a service is not known and
+	// StrictMatching is not enabled a dualstack endpoint for the service will
+	// be returned. This endpoint may not be valid. If StrictMatching is
+	// enabled only services that are known to support dualstack will return
+	// dualstack endpoints.
+	UseDualStack bool
+
+	// Enables strict matching of services and regions resolved endpoints.
+	// If the partition doesn't enumerate the exact service and region an
+	// error will be returned. This option will prevent returning endpoints
+	// that look valid, but may not resolve to any real endpoint.
+	StrictMatching bool
+
+	// Enables resolving a service endpoint based on the region provided if the
+	// service does not exist. The service endpoint ID will be used as the service
+	// domain name prefix. By default the endpoint resolver requires the service
+	// to be known when resolving endpoints.
+	//
+	// If resolving an endpoint on the partition list the provided region will
+	// be used to determine which partition's domain name pattern to the service
+	// endpoint ID with. If both the service and region are unkonwn and resolving
+	// the endpoint on partition list an UnknownEndpointError error will be returned.
+	//
+	// If resolving and endpoint on a partition specific resolver that partition's
+	// domain name pattern will be used with the service endpoint ID. If both
+	// region and service do not exist when resolving an endpoint on a specific
+	// partition the partition's domain pattern will be used to combine the
+	// endpoint and region together.
+	//
+	// This option is ignored if StrictMatching is enabled.
+	ResolveUnknownService bool
+}
+
+// Set combines all of the option functions together.
+func (o *Options) Set(optFns ...func(*Options)) {
+	for _, fn := range optFns {
+		fn(o)
+	}
+}
+
+// DisableSSLOption sets the DisableSSL options. Can be used as a functional
+// option when resolving endpoints.
+func DisableSSLOption(o *Options) {
+	o.DisableSSL = true
+}
+
+// UseDualStackOption sets the UseDualStack option. Can be used as a functional
+// option when resolving endpoints.
+func UseDualStackOption(o *Options) {
+	o.UseDualStack = true
+}
+
+// StrictMatchingOption sets the StrictMatching option. Can be used as a functional
+// option when resolving endpoints.
+func StrictMatchingOption(o *Options) {
+	o.StrictMatching = true
+}
+
+// ResolveUnknownServiceOption sets the ResolveUnknownService option. Can be used
+// as a functional option when resolving endpoints.
+func ResolveUnknownServiceOption(o *Options) {
+	o.ResolveUnknownService = true
+}
+
+// A Resolver provides the interface for functionality to resolve endpoints.
+// The build in Partition and DefaultResolver return value satisfy this interface.
+type Resolver interface {
+	EndpointFor(service, region string, opts ...func(*Options)) (ResolvedEndpoint, error)
+}
+
+// ResolverFunc is a helper utility that wraps a function so it satisfies the
+// Resolver interface. This is useful when you want to add additional endpoint
+// resolving logic, or stub out specific endpoints with custom values.
+type ResolverFunc func(service, region string, opts ...func(*Options)) (ResolvedEndpoint, error)
+
+// EndpointFor wraps the ResolverFunc function to satisfy the Resolver interface.
+func (fn ResolverFunc) EndpointFor(service, region string, opts ...func(*Options)) (ResolvedEndpoint, error) {
+	return fn(service, region, opts...)
+}
+
+var schemeRE = regexp.MustCompile("^([^:]+)://")
+
+// AddScheme adds the HTTP or HTTPS schemes to a endpoint URL if there is no
+// scheme. If disableSSL is true HTTP will set HTTP instead of the default HTTPS.
+//
+// If disableSSL is set, it will only set the URL's scheme if the URL does not
+// contain a scheme.
+func AddScheme(endpoint string, disableSSL bool) string {
+	if !schemeRE.MatchString(endpoint) {
+		scheme := "https"
+		if disableSSL {
+			scheme = "http"
+		}
+		endpoint = fmt.Sprintf("%s://%s", scheme, endpoint)
+	}
+
+	return endpoint
+}
+
+// EnumPartitions a provides a way to retrieve the underlying partitions that
+// make up the SDK's default Resolver, or any resolver decoded from a model
+// file.
+//
+// Use this interface with DefaultResolver and DecodeModels to get the list of
+// Partitions.
+type EnumPartitions interface {
+	Partitions() []Partition
+}
+
+// RegionsForService returns a map of regions for the partition and service.
+// If either the partition or service does not exist false will be returned
+// as the second parameter.
+//
+// This example shows how  to get the regions for DynamoDB in the AWS partition.
+//    rs, exists := endpoints.RegionsForService(endpoints.DefaultPartitions(), endpoints.AwsPartitionID, endpoints.DynamodbServiceID)
+//
+// This is equivalent to using the partition directly.
+//    rs := endpoints.AwsPartition().Services()[endpoints.DynamodbServiceID].Regions()
+func RegionsForService(ps []Partition, partitionID, serviceID string) (map[string]Region, bool) {
+	for _, p := range ps {
+		if p.ID() != partitionID {
+			continue
+		}
+		if _, ok := p.p.Services[serviceID]; !ok {
+			break
+		}
+
+		s := Service{
+			id: serviceID,
+			p:  p.p,
+		}
+		return s.Regions(), true
+	}
+
+	return map[string]Region{}, false
+}
+
+// PartitionForRegion returns the first partition which includes the region
+// passed in. This includes both known regions and regions which match
+// a pattern supported by the partition which may include regions that are
+// not explicitly known by the partition. Use the Regions method of the
+// returned Partition if explicit support is needed.
+func PartitionForRegion(ps []Partition, regionID string) (Partition, bool) {
+	for _, p := range ps {
+		if _, ok := p.p.Regions[regionID]; ok || p.p.RegionRegex.MatchString(regionID) {
+			return p, true
+		}
+	}
+
+	return Partition{}, false
+}
+
+// A Partition provides the ability to enumerate the partition's regions
+// and services.
+type Partition struct {
+	id string
+	p  *partition
+}
+
+// ID returns the identifier of the partition.
+func (p Partition) ID() string { return p.id }
+
+// EndpointFor attempts to resolve the endpoint based on service and region.
+// See Options for information on configuring how the endpoint is resolved.
+//
+// If the service cannot be found in the metadata the UnknownServiceError
+// error will be returned. This validation will occur regardless if
+// StrictMatching is enabled. To enable resolving unknown services set the
+// "ResolveUnknownService" option to true. When StrictMatching is disabled
+// this option allows the partition resolver to resolve a endpoint based on
+// the service endpoint ID provided.
+//
+// When resolving endpoints you can choose to enable StrictMatching. This will
+// require the provided service and region to be known by the partition.
+// If the endpoint cannot be strictly resolved an error will be returned. This
+// mode is useful to ensure the endpoint resolved is valid. Without
+// StrictMatching enabled the endpoint returned my look valid but may not work.
+// StrictMatching requires the SDK to be updated if you want to take advantage
+// of new regions and services expansions.
+//
+// Errors that can be returned.
+//   * UnknownServiceError
+//   * UnknownEndpointError
+func (p Partition) EndpointFor(service, region string, opts ...func(*Options)) (ResolvedEndpoint, error) {
+	return p.p.EndpointFor(service, region, opts...)
+}
+
+// Regions returns a map of Regions indexed by their ID. This is useful for
+// enumerating over the regions in a partition.
+func (p Partition) Regions() map[string]Region {
+	rs := map[string]Region{}
+	for id := range p.p.Regions {
+		rs[id] = Region{
+			id: id,
+			p:  p.p,
+		}
+	}
+
+	return rs
+}
+
+// Services returns a map of Service indexed by their ID. This is useful for
+// enumerating over the services in a partition.
+func (p Partition) Services() map[string]Service {
+	ss := map[string]Service{}
+	for id := range p.p.Services {
+		ss[id] = Service{
+			id: id,
+			p:  p.p,
+		}
+	}
+
+	return ss
+}
+
+// A Region provides information about a region, and ability to resolve an
+// endpoint from the context of a region, given a service.
+type Region struct {
+	id, desc string
+	p        *partition
+}
+
+// ID returns the region's identifier.
+func (r Region) ID() string { return r.id }
+
+// ResolveEndpoint resolves an endpoint from the context of the region given
+// a service. See Partition.EndpointFor for usage and errors that can be returned.
+func (r Region) ResolveEndpoint(service string, opts ...func(*Options)) (ResolvedEndpoint, error) {
+	return r.p.EndpointFor(service, r.id, opts...)
+}
+
+// Services returns a list of all services that are known to be in this region.
+func (r Region) Services() map[string]Service {
+	ss := map[string]Service{}
+	for id, s := range r.p.Services {
+		if _, ok := s.Endpoints[r.id]; ok {
+			ss[id] = Service{
+				id: id,
+				p:  r.p,
+			}
+		}
+	}
+
+	return ss
+}
+
+// A Service provides information about a service, and ability to resolve an
+// endpoint from the context of a service, given a region.
+type Service struct {
+	id string
+	p  *partition
+}
+
+// ID returns the identifier for the service.
+func (s Service) ID() string { return s.id }
+
+// ResolveEndpoint resolves an endpoint from the context of a service given
+// a region. See Partition.EndpointFor for usage and errors that can be returned.
+func (s Service) ResolveEndpoint(region string, opts ...func(*Options)) (ResolvedEndpoint, error) {
+	return s.p.EndpointFor(s.id, region, opts...)
+}
+
+// Regions returns a map of Regions that the service is present in.
+//
+// A region is the AWS region the service exists in. Whereas a Endpoint is
+// an URL that can be resolved to a instance of a service.
+func (s Service) Regions() map[string]Region {
+	rs := map[string]Region{}
+	for id := range s.p.Services[s.id].Endpoints {
+		if _, ok := s.p.Regions[id]; ok {
+			rs[id] = Region{
+				id: id,
+				p:  s.p,
+			}
+		}
+	}
+
+	return rs
+}
+
+// Endpoints returns a map of Endpoints indexed by their ID for all known
+// endpoints for a service.
+//
+// A region is the AWS region the service exists in. Whereas a Endpoint is
+// an URL that can be resolved to a instance of a service.
+func (s Service) Endpoints() map[string]Endpoint {
+	es := map[string]Endpoint{}
+	for id := range s.p.Services[s.id].Endpoints {
+		es[id] = Endpoint{
+			id:        id,
+			serviceID: s.id,
+			p:         s.p,
+		}
+	}
+
+	return es
+}
+
+// A Endpoint provides information about endpoints, and provides the ability
+// to resolve that endpoint for the service, and the region the endpoint
+// represents.
+type Endpoint struct {
+	id        string
+	serviceID string
+	p         *partition
+}
+
+// ID returns the identifier for an endpoint.
+func (e Endpoint) ID() string { return e.id }
+
+// ServiceID returns the identifier the endpoint belongs to.
+func (e Endpoint) ServiceID() string { return e.serviceID }
+
+// ResolveEndpoint resolves an endpoint from the context of a service and
+// region the endpoint represents. See Partition.EndpointFor for usage and
+// errors that can be returned.
+func (e Endpoint) ResolveEndpoint(opts ...func(*Options)) (ResolvedEndpoint, error) {
+	return e.p.EndpointFor(e.serviceID, e.id, opts...)
+}
+
+// A ResolvedEndpoint is an endpoint that has been resolved based on a partition
+// service, and region.
+type ResolvedEndpoint struct {
+	// The endpoint URL
+	URL string
+
+	// The region that should be used for signing requests.
+	SigningRegion string
+
+	// The service name that should be used for signing requests.
+	SigningName string
+
+	// States that the signing name for this endpoint was derived from metadata
+	// passed in, but was not explicitly modeled.
+	SigningNameDerived bool
+
+	// The signing method that should be used for signing requests.
+	SigningMethod string
+}
+
+// So that the Error interface type can be included as an anonymous field
+// in the requestError struct and not conflict with the error.Error() method.
+type awsError awserr.Error
+
+// A EndpointNotFoundError is returned when in StrictMatching mode, and the
+// endpoint for the service and region cannot be found in any of the partitions.
+type EndpointNotFoundError struct {
+	awsError
+	Partition string
+	Service   string
+	Region    string
+}
+
+// A UnknownServiceError is returned when the service does not resolve to an
+// endpoint. Includes a list of all known services for the partition. Returned
+// when a partition does not support the service.
+type UnknownServiceError struct {
+	awsError
+	Partition string
+	Service   string
+	Known     []string
+}
+
+// NewUnknownServiceError builds and returns UnknownServiceError.
+func NewUnknownServiceError(p, s string, known []string) UnknownServiceError {
+	return UnknownServiceError{
+		awsError: awserr.New("UnknownServiceError",
+			"could not resolve endpoint for unknown service", nil),
+		Partition: p,
+		Service:   s,
+		Known:     known,
+	}
+}
+
+// String returns the string representation of the error.
+func (e UnknownServiceError) Error() string {
+	extra := fmt.Sprintf("partition: %q, service: %q",
+		e.Partition, e.Service)
+	if len(e.Known) > 0 {
+		extra += fmt.Sprintf(", known: %v", e.Known)
+	}
+	return awserr.SprintError(e.Code(), e.Message(), extra, e.OrigErr())
+}
+
+// String returns the string representation of the error.
+func (e UnknownServiceError) String() string {
+	return e.Error()
+}
+
+// A UnknownEndpointError is returned when in StrictMatching mode and the
+// service is valid, but the region does not resolve to an endpoint. Includes
+// a list of all known endpoints for the service.
+type UnknownEndpointError struct {
+	awsError
+	Partition string
+	Service   string
+	Region    string
+	Known     []string
+}
+
+// NewUnknownEndpointError builds and returns UnknownEndpointError.
+func NewUnknownEndpointError(p, s, r string, known []string) UnknownEndpointError {
+	return UnknownEndpointError{
+		awsError: awserr.New("UnknownEndpointError",
+			"could not resolve endpoint", nil),
+		Partition: p,
+		Service:   s,
+		Region:    r,
+		Known:     known,
+	}
+}
+
+// String returns the string representation of the error.
+func (e UnknownEndpointError) Error() string {
+	extra := fmt.Sprintf("partition: %q, service: %q, region: %q",
+		e.Partition, e.Service, e.Region)
+	if len(e.Known) > 0 {
+		extra += fmt.Sprintf(", known: %v", e.Known)
+	}
+	return awserr.SprintError(e.Code(), e.Message(), extra, e.OrigErr())
+}
+
+// String returns the string representation of the error.
+func (e UnknownEndpointError) String() string {
+	return e.Error()
+}
@@ -0,0 +1,307 @@
+package endpoints
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type partitions []partition
+
+func (ps partitions) EndpointFor(service, region string, opts ...func(*Options)) (ResolvedEndpoint, error) {
+	var opt Options
+	opt.Set(opts...)
+
+	for i := 0; i < len(ps); i++ {
+		if !ps[i].canResolveEndpoint(service, region, opt.StrictMatching) {
+			continue
+		}
+
+		return ps[i].EndpointFor(service, region, opts...)
+	}
+
+	// If loose matching fallback to first partition format to use
+	// when resolving the endpoint.
+	if !opt.StrictMatching && len(ps) > 0 {
+		return ps[0].EndpointFor(service, region, opts...)
+	}
+
+	return ResolvedEndpoint{}, NewUnknownEndpointError("all partitions", service, region, []string{})
+}
+
+// Partitions satisfies the EnumPartitions interface and returns a list
+// of Partitions representing each partition represented in the SDK's
+// endpoints model.
+func (ps partitions) Partitions() []Partition {
+	parts := make([]Partition, 0, len(ps))
+	for i := 0; i < len(ps); i++ {
+		parts = append(parts, ps[i].Partition())
+	}
+
+	return parts
+}
+
+type partition struct {
+	ID          string      `json:"partition"`
+	Name        string      `json:"partitionName"`
+	DNSSuffix   string      `json:"dnsSuffix"`
+	RegionRegex regionRegex `json:"regionRegex"`
+	Defaults    endpoint    `json:"defaults"`
+	Regions     regions     `json:"regions"`
+	Services    services    `json:"services"`
+}
+
+func (p partition) Partition() Partition {
+	return Partition{
+		id: p.ID,
+		p:  &p,
+	}
+}
+
+func (p partition) canResolveEndpoint(service, region string, strictMatch bool) bool {
+	s, hasService := p.Services[service]
+	_, hasEndpoint := s.Endpoints[region]
+
+	if hasEndpoint && hasService {
+		return true
+	}
+
+	if strictMatch {
+		return false
+	}
+
+	return p.RegionRegex.MatchString(region)
+}
+
+func (p partition) EndpointFor(service, region string, opts ...func(*Options)) (resolved ResolvedEndpoint, err error) {
+	var opt Options
+	opt.Set(opts...)
+
+	s, hasService := p.Services[service]
+	if !(hasService || opt.ResolveUnknownService) {
+		// Only return error if the resolver will not fallback to creating
+		// endpoint based on service endpoint ID passed in.
+		return resolved, NewUnknownServiceError(p.ID, service, serviceList(p.Services))
+	}
+
+	e, hasEndpoint := s.endpointForRegion(region)
+	if !hasEndpoint && opt.StrictMatching {
+		return resolved, NewUnknownEndpointError(p.ID, service, region, endpointList(s.Endpoints))
+	}
+
+	defs := []endpoint{p.Defaults, s.Defaults}
+	return e.resolve(service, region, p.DNSSuffix, defs, opt), nil
+}
+
+func serviceList(ss services) []string {
+	list := make([]string, 0, len(ss))
+	for k := range ss {
+		list = append(list, k)
+	}
+	return list
+}
+func endpointList(es endpoints) []string {
+	list := make([]string, 0, len(es))
+	for k := range es {
+		list = append(list, k)
+	}
+	return list
+}
+
+type regionRegex struct {
+	*regexp.Regexp
+}
+
+func (rr *regionRegex) UnmarshalJSON(b []byte) (err error) {
+	// Strip leading and trailing quotes
+	regex, err := strconv.Unquote(string(b))
+	if err != nil {
+		return fmt.Errorf("unable to strip quotes from regex, %v", err)
+	}
+
+	rr.Regexp, err = regexp.Compile(regex)
+	if err != nil {
+		return fmt.Errorf("unable to unmarshal region regex, %v", err)
+	}
+	return nil
+}
+
+type regions map[string]region
+
+type region struct {
+	Description string `json:"description"`
+}
+
+type services map[string]service
+
+type service struct {
+	PartitionEndpoint string    `json:"partitionEndpoint"`
+	IsRegionalized    boxedBool `json:"isRegionalized,omitempty"`
+	Defaults          endpoint  `json:"defaults"`
+	Endpoints         endpoints `json:"endpoints"`
+}
+
+func (s *service) endpointForRegion(region string) (endpoint, bool) {
+	if s.IsRegionalized == boxedFalse {
+		return s.Endpoints[s.PartitionEndpoint], region == s.PartitionEndpoint
+	}
+
+	if e, ok := s.Endpoints[region]; ok {
+		return e, true
+	}
+
+	// Unable to find any matching endpoint, return
+	// blank that will be used for generic endpoint creation.
+	return endpoint{}, false
+}
+
+type endpoints map[string]endpoint
+
+type endpoint struct {
+	Hostname        string          `json:"hostname"`
+	Protocols       []string        `json:"protocols"`
+	CredentialScope credentialScope `json:"credentialScope"`
+
+	// Custom fields not modeled
+	HasDualStack      boxedBool `json:"-"`
+	DualStackHostname string    `json:"-"`
+
+	// Signature Version not used
+	SignatureVersions []string `json:"signatureVersions"`
+
+	// SSLCommonName not used.
+	SSLCommonName string `json:"sslCommonName"`
+}
+
+const (
+	defaultProtocol = "https"
+	defaultSigner   = "v4"
+)
+
+var (
+	protocolPriority = []string{"https", "http"}
+	signerPriority   = []string{"v4", "v2"}
+)
+
+func getByPriority(s []string, p []string, def string) string {
+	if len(s) == 0 {
+		return def
+	}
+
+	for i := 0; i < len(p); i++ {
+		for j := 0; j < len(s); j++ {
+			if s[j] == p[i] {
+				return s[j]
+			}
+		}
+	}
+
+	return s[0]
+}
+
+func (e endpoint) resolve(service, region, dnsSuffix string, defs []endpoint, opts Options) ResolvedEndpoint {
+	var merged endpoint
+	for _, def := range defs {
+		merged.mergeIn(def)
+	}
+	merged.mergeIn(e)
+	e = merged
+
+	hostname := e.Hostname
+
+	// Offset the hostname for dualstack if enabled
+	if opts.UseDualStack && e.HasDualStack == boxedTrue {
+		hostname = e.DualStackHostname
+	}
+
+	u := strings.Replace(hostname, "{service}", service, 1)
+	u = strings.Replace(u, "{region}", region, 1)
+	u = strings.Replace(u, "{dnsSuffix}", dnsSuffix, 1)
+
+	scheme := getEndpointScheme(e.Protocols, opts.DisableSSL)
+	u = fmt.Sprintf("%s://%s", scheme, u)
+
+	signingRegion := e.CredentialScope.Region
+	if len(signingRegion) == 0 {
+		signingRegion = region
+	}
+
+	signingName := e.CredentialScope.Service
+	var signingNameDerived bool
+	if len(signingName) == 0 {
+		signingName = service
+		signingNameDerived = true
+	}
+
+	return ResolvedEndpoint{
+		URL:                u,
+		SigningRegion:      signingRegion,
+		SigningName:        signingName,
+		SigningNameDerived: signingNameDerived,
+		SigningMethod:      getByPriority(e.SignatureVersions, signerPriority, defaultSigner),
+	}
+}
+
+func getEndpointScheme(protocols []string, disableSSL bool) string {
+	if disableSSL {
+		return "http"
+	}
+
+	return getByPriority(protocols, protocolPriority, defaultProtocol)
+}
+
+func (e *endpoint) mergeIn(other endpoint) {
+	if len(other.Hostname) > 0 {
+		e.Hostname = other.Hostname
+	}
+	if len(other.Protocols) > 0 {
+		e.Protocols = other.Protocols
+	}
+	if len(other.SignatureVersions) > 0 {
+		e.SignatureVersions = other.SignatureVersions
+	}
+	if len(other.CredentialScope.Region) > 0 {
+		e.CredentialScope.Region = other.CredentialScope.Region
+	}
+	if len(other.CredentialScope.Service) > 0 {
+		e.CredentialScope.Service = other.CredentialScope.Service
+	}
+	if len(other.SSLCommonName) > 0 {
+		e.SSLCommonName = other.SSLCommonName
+	}
+	if other.HasDualStack != boxedBoolUnset {
+		e.HasDualStack = other.HasDualStack
+	}
+	if len(other.DualStackHostname) > 0 {
+		e.DualStackHostname = other.DualStackHostname
+	}
+}
+
+type credentialScope struct {
+	Region  string `json:"region"`
+	Service string `json:"service"`
+}
+
+type boxedBool int
+
+func (b *boxedBool) UnmarshalJSON(buf []byte) error {
+	v, err := strconv.ParseBool(string(buf))
+	if err != nil {
+		return err
+	}
+
+	if v {
+		*b = boxedTrue
+	} else {
+		*b = boxedFalse
+	}
+
+	return nil
+}
+
+const (
+	boxedBoolUnset boxedBool = iota
+	boxedFalse
+	boxedTrue
+)
@@ -0,0 +1,337 @@
+// +build codegen
+
+package endpoints
+
+import (
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+	"text/template"
+	"unicode"
+)
+
+// A CodeGenOptions are the options for code generating the endpoints into
+// Go code from the endpoints model definition.
+type CodeGenOptions struct {
+	// Options for how the model will be decoded.
+	DecodeModelOptions DecodeModelOptions
+}
+
+// Set combines all of the option functions together
+func (d *CodeGenOptions) Set(optFns ...func(*CodeGenOptions)) {
+	for _, fn := range optFns {
+		fn(d)
+	}
+}
+
+// CodeGenModel given a endpoints model file will decode it and attempt to
+// generate Go code from the model definition. Error will be returned if
+// the code is unable to be generated, or decoded.
+func CodeGenModel(modelFile io.Reader, outFile io.Writer, optFns ...func(*CodeGenOptions)) error {
+	var opts CodeGenOptions
+	opts.Set(optFns...)
+
+	resolver, err := DecodeModel(modelFile, func(d *DecodeModelOptions) {
+		*d = opts.DecodeModelOptions
+	})
+	if err != nil {
+		return err
+	}
+
+	tmpl := template.Must(template.New("tmpl").Funcs(funcMap).Parse(v3Tmpl))
+	if err := tmpl.ExecuteTemplate(outFile, "defaults", resolver); err != nil {
+		return fmt.Errorf("failed to execute template, %v", err)
+	}
+
+	return nil
+}
+
+func toSymbol(v string) string {
+	out := []rune{}
+	for _, c := range strings.Title(v) {
+		if !(unicode.IsNumber(c) || unicode.IsLetter(c)) {
+			continue
+		}
+
+		out = append(out, c)
+	}
+
+	return string(out)
+}
+
+func quoteString(v string) string {
+	return fmt.Sprintf("%q", v)
+}
+
+func regionConstName(p, r string) string {
+	return toSymbol(p) + toSymbol(r)
+}
+
+func partitionGetter(id string) string {
+	return fmt.Sprintf("%sPartition", toSymbol(id))
+}
+
+func partitionVarName(id string) string {
+	return fmt.Sprintf("%sPartition", strings.ToLower(toSymbol(id)))
+}
+
+func listPartitionNames(ps partitions) string {
+	names := []string{}
+	switch len(ps) {
+	case 1:
+		return ps[0].Name
+	case 2:
+		return fmt.Sprintf("%s and %s", ps[0].Name, ps[1].Name)
+	default:
+		for i, p := range ps {
+			if i == len(ps)-1 {
+				names = append(names, "and "+p.Name)
+			} else {
+				names = append(names, p.Name)
+			}
+		}
+		return strings.Join(names, ", ")
+	}
+}
+
+func boxedBoolIfSet(msg string, v boxedBool) string {
+	switch v {
+	case boxedTrue:
+		return fmt.Sprintf(msg, "boxedTrue")
+	case boxedFalse:
+		return fmt.Sprintf(msg, "boxedFalse")
+	default:
+		return ""
+	}
+}
+
+func stringIfSet(msg, v string) string {
+	if len(v) == 0 {
+		return ""
+	}
+
+	return fmt.Sprintf(msg, v)
+}
+
+func stringSliceIfSet(msg string, vs []string) string {
+	if len(vs) == 0 {
+		return ""
+	}
+
+	names := []string{}
+	for _, v := range vs {
+		names = append(names, `"`+v+`"`)
+	}
+
+	return fmt.Sprintf(msg, strings.Join(names, ","))
+}
+
+func endpointIsSet(v endpoint) bool {
+	return !reflect.DeepEqual(v, endpoint{})
+}
+
+func serviceSet(ps partitions) map[string]struct{} {
+	set := map[string]struct{}{}
+	for _, p := range ps {
+		for id := range p.Services {
+			set[id] = struct{}{}
+		}
+	}
+
+	return set
+}
+
+var funcMap = template.FuncMap{
+	"ToSymbol":           toSymbol,
+	"QuoteString":        quoteString,
+	"RegionConst":        regionConstName,
+	"PartitionGetter":    partitionGetter,
+	"PartitionVarName":   partitionVarName,
+	"ListPartitionNames": listPartitionNames,
+	"BoxedBoolIfSet":     boxedBoolIfSet,
+	"StringIfSet":        stringIfSet,
+	"StringSliceIfSet":   stringSliceIfSet,
+	"EndpointIsSet":      endpointIsSet,
+	"ServicesSet":        serviceSet,
+}
+
+const v3Tmpl = `
+{{ define "defaults" -}}
+// Code generated by aws/endpoints/v3model_codegen.go. DO NOT EDIT.
+
+package endpoints
+
+import (
+	"regexp"
+)
+
+	{{ template "partition consts" . }}
+
+	{{ range $_, $partition := . }}
+		{{ template "partition region consts" $partition }}
+	{{ end }}
+
+	{{ template "service consts" . }}
+	
+	{{ template "endpoint resolvers" . }}
+{{- end }}
+
+{{ define "partition consts" }}
+	// Partition identifiers
+	const (
+		{{ range $_, $p := . -}}
+			{{ ToSymbol $p.ID }}PartitionID = {{ QuoteString $p.ID }} // {{ $p.Name }} partition.
+		{{ end -}}
+	)
+{{- end }}
+
+{{ define "partition region consts" }}
+	// {{ .Name }} partition's regions.
+	const (
+		{{ range $id, $region := .Regions -}}
+			{{ ToSymbol $id }}RegionID = {{ QuoteString $id }} // {{ $region.Description }}.
+		{{ end -}}
+	)
+{{- end }}
+
+{{ define "service consts" }}
+	// Service identifiers
+	const (
+		{{ $serviceSet := ServicesSet . -}}
+		{{ range $id, $_ := $serviceSet -}}
+			{{ ToSymbol $id }}ServiceID = {{ QuoteString $id }} // {{ ToSymbol $id }}.
+		{{ end -}}
+	)
+{{- end }}
+
+{{ define "endpoint resolvers" }}
+	// DefaultResolver returns an Endpoint resolver that will be able
+	// to resolve endpoints for: {{ ListPartitionNames . }}.
+	//
+	// Use DefaultPartitions() to get the list of the default partitions.
+	func DefaultResolver() Resolver {
+		return defaultPartitions
+	}
+
+	// DefaultPartitions returns a list of the partitions the SDK is bundled
+	// with. The available partitions are: {{ ListPartitionNames . }}.
+	//
+	//    partitions := endpoints.DefaultPartitions
+	//    for _, p := range partitions {
+	//        // ... inspect partitions
+	//    }
+	func DefaultPartitions() []Partition {
+		return defaultPartitions.Partitions()
+	}
+
+	var defaultPartitions = partitions{
+		{{ range $_, $partition := . -}}
+			{{ PartitionVarName $partition.ID }},
+		{{ end }}
+	}
+	
+	{{ range $_, $partition := . -}}
+		{{ $name := PartitionGetter $partition.ID -}}
+		// {{ $name }} returns the Resolver for {{ $partition.Name }}.
+		func {{ $name }}() Partition {
+			return  {{ PartitionVarName $partition.ID }}.Partition()
+		}
+		var {{ PartitionVarName $partition.ID }} = {{ template "gocode Partition" $partition }}
+	{{ end }}
+{{ end }}
+
+{{ define "default partitions" }}
+	func DefaultPartitions() []Partition {
+		return []partition{
+			{{ range $_, $partition := . -}}
+			// {{ ToSymbol $partition.ID}}Partition(),
+			{{ end }}
+		}
+	}
+{{ end }}
+
+{{ define "gocode Partition" -}}
+partition{
+	{{ StringIfSet "ID: %q,\n" .ID -}}
+	{{ StringIfSet "Name: %q,\n" .Name -}}
+	{{ StringIfSet "DNSSuffix: %q,\n" .DNSSuffix -}}
+	RegionRegex: {{ template "gocode RegionRegex" .RegionRegex }},
+	{{ if EndpointIsSet .Defaults -}}
+		Defaults: {{ template "gocode Endpoint" .Defaults }},
+	{{- end }}
+	Regions:  {{ template "gocode Regions" .Regions }},
+	Services: {{ template "gocode Services" .Services }},
+}
+{{- end }}
+
+{{ define "gocode RegionRegex" -}}
+regionRegex{
+	Regexp: func() *regexp.Regexp{
+		reg, _ := regexp.Compile({{ QuoteString .Regexp.String }})
+		return reg
+	}(),
+}
+{{- end }}
+
+{{ define "gocode Regions" -}}
+regions{
+	{{ range $id, $region := . -}}
+		"{{ $id }}": {{ template "gocode Region" $region }},
+	{{ end -}}
+}
+{{- end }}
+
+{{ define "gocode Region" -}}
+region{
+	{{ StringIfSet "Description: %q,\n" .Description -}}
+}
+{{- end }}
+
+{{ define "gocode Services" -}}
+services{
+	{{ range $id, $service := . -}}
+	"{{ $id }}": {{ template "gocode Service" $service }},
+	{{ end }}
+}
+{{- end }}
+
+{{ define "gocode Service" -}}
+service{
+	{{ StringIfSet "PartitionEndpoint: %q,\n" .PartitionEndpoint -}}
+	{{ BoxedBoolIfSet "IsRegionalized: %s,\n" .IsRegionalized -}}
+	{{ if EndpointIsSet .Defaults -}}
+		Defaults: {{ template "gocode Endpoint" .Defaults -}},
+	{{- end }}
+	{{ if .Endpoints -}}
+		Endpoints: {{ template "gocode Endpoints" .Endpoints }},
+	{{- end }}
+}
+{{- end }}
+
+{{ define "gocode Endpoints" -}}
+endpoints{
+	{{ range $id, $endpoint := . -}}
+	"{{ $id }}": {{ template "gocode Endpoint" $endpoint }},
+	{{ end }}
+}
+{{- end }}
+
+{{ define "gocode Endpoint" -}}
+endpoint{
+	{{ StringIfSet "Hostname: %q,\n" .Hostname -}}
+	{{ StringIfSet "SSLCommonName: %q,\n" .SSLCommonName -}}
+	{{ StringSliceIfSet "Protocols: []string{%s},\n" .Protocols -}}
+	{{ StringSliceIfSet "SignatureVersions: []string{%s},\n" .SignatureVersions -}}
+	{{ if or .CredentialScope.Region .CredentialScope.Service -}}
+	CredentialScope: credentialScope{
+		{{ StringIfSet "Region: %q,\n" .CredentialScope.Region -}}
+		{{ StringIfSet "Service: %q,\n" .CredentialScope.Service -}}
+	},
+	{{- end }}
+	{{ BoxedBoolIfSet "HasDualStack: %s,\n" .HasDualStack -}}
+	{{ StringIfSet "DualStackHostname: %q,\n" .DualStackHostname -}}
+
+}
+{{- end }}
+`
@@ -0,0 +1,17 @@
+package aws
+
+import "github.com/aws/aws-sdk-go/aws/awserr"
+
+var (
+	// ErrMissingRegion is an error that is returned if region configuration is
+	// not found.
+	//
+	// @readonly
+	ErrMissingRegion = awserr.New("MissingRegion", "could not find region configuration", nil)
+
+	// ErrMissingEndpoint is an error that is returned if an endpoint cannot be
+	// resolved for a service.
+	//
+	// @readonly
+	ErrMissingEndpoint = awserr.New("MissingEndpoint", "'Endpoint' configuration is required for this service", nil)
+)