pkg/term/term_windows.go - third_party/github.com/moby/moby - Git at Google

 // +build windows

 package term

 import (
 	"io"
 	"os"
 	"os/signal"
 	"syscall"

 	"github.com/Azure/go-ansiterm/winterm"
 	"github.com/docker/docker/pkg/system"
 	"github.com/docker/docker/pkg/term/windows"
 )

 // State holds the console mode for the terminal.
 type State struct {
 	inMode, outMode     uint32
 	inHandle, outHandle syscall.Handle
 }

 // Winsize is used for window size.
 type Winsize struct {
 	Height uint16
 	Width  uint16
 	x      uint16
 	y      uint16
 }

 const (
 	// https://msdn.microsoft.com/en-us/library/windows/desktop/ms683167(v=vs.85).aspx
 	enableVirtualTerminalInput      = 0x0200
 	enableVirtualTerminalProcessing = 0x0004
 )

 // usingNativeConsole is true if we are using the Windows native console
 var usingNativeConsole bool

 // StdStreams returns the standard streams (stdin, stdout, stedrr).
 func StdStreams() (stdIn io.ReadCloser, stdOut, stdErr io.Writer) {
 	switch {
 	case os.Getenv("ConEmuANSI") == "ON":
 		// The ConEmu terminal emulates ANSI on output streams well.
 		return windows.ConEmuStreams()
 	case os.Getenv("MSYSTEM") != "":
 		// MSYS (mingw) does not emulate ANSI well.
 		return windows.ConsoleStreams()
 	default:
 		if useNativeConsole() {
 			usingNativeConsole = true
 			return os.Stdin, os.Stdout, os.Stderr
 		}
 		return windows.ConsoleStreams()
 	}
 }

 // useNativeConsole determines if the docker client should use the built-in
 // console which supports ANSI emulation, or fall-back to the golang emulator
 // (github.com/azure/go-ansiterm).
 func useNativeConsole() bool {
 	osv, err := system.GetOSVersion()
 	if err != nil {
 		return false
 	}

 	// Native console is not available before major version 10
 	if osv.MajorVersion < 10 {
 		return false
 	}

 	// Must have a late pre-release TP4 build of Windows Server 2016/Windows 10 TH2 or later
 	if osv.Build < 10578 {
 		return false
 	}

 	// Get the console modes. If this fails, we can't use the native console
 	state, err := getNativeConsole()
 	if err != nil {
 		return false
 	}

 	// Probe the console to see if it can be enabled.
 	if nil != probeNativeConsole(state) {
 		return false
 	}

 	// Environment variable override
 	if e := os.Getenv("USE_NATIVE_CONSOLE"); e != "" {
 		if e == "1" {
 			return true
 		}
 		return false
 	}

 	// TODO Windows. The native emulator still has issues which
 	// mean it shouldn't be enabled for everyone. Change this next line to true
 	// to change the default to "enable if available". In the meantime, users
 	// can still try it out by using USE_NATIVE_CONSOLE env variable.
 	return false
 }

 // getNativeConsole returns the console modes ('state') for the native Windows console
 func getNativeConsole() (State, error) {
 	var (
 		err   error
 		state State
 	)

 	// Get the handle to stdout
 	if state.outHandle, err = syscall.GetStdHandle(syscall.STD_OUTPUT_HANDLE); err != nil {
 		return state, err
 	}

 	// Get the console mode from the consoles stdout handle
 	if err = syscall.GetConsoleMode(state.outHandle, &state.outMode); err != nil {
 		return state, err
 	}

 	// Get the handle to stdin
 	if state.inHandle, err = syscall.GetStdHandle(syscall.STD_INPUT_HANDLE); err != nil {
 		return state, err
 	}

 	// Get the console mode from the consoles stdin handle
 	if err = syscall.GetConsoleMode(state.inHandle, &state.inMode); err != nil {
 		return state, err
 	}

 	return state, nil
 }

 // probeNativeConsole probes the console to determine if native can be supported,
 func probeNativeConsole(state State) error {
 	if err := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode|enableVirtualTerminalProcessing); err != nil {
 		return err
 	}
 	defer winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode)

 	if err := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode|enableVirtualTerminalInput); err != nil {
 		return err
 	}
 	defer winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode)

 	return nil
 }

 // enableNativeConsole turns on native console mode
 func enableNativeConsole(state State) error {
 	if err := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode|enableVirtualTerminalProcessing); err != nil {
 		return err
 	}

 	if err := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode|enableVirtualTerminalInput); err != nil {
 		winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode) // restore out if we can
 		return err
 	}

 	return nil
 }

 // disableNativeConsole turns off native console mode
 func disableNativeConsole(state *State) error {
 	// Try and restore both in an out before error checking.
 	errout := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode)
 	errin := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode)
 	if errout != nil {
 		return errout
 	}
 	if errin != nil {
 		return errin
 	}
 	return nil
 }

 // GetFdInfo returns the file descriptor for an os.File and indicates whether the file represents a terminal.
 func GetFdInfo(in interface{}) (uintptr, bool) {
 	return windows.GetHandleInfo(in)
 }

 // GetWinsize returns the window size based on the specified file descriptor.
 func GetWinsize(fd uintptr) (*Winsize, error) {
 	info, err := winterm.GetConsoleScreenBufferInfo(fd)
 	if err != nil {
 		return nil, err
 	}

 	winsize := &Winsize{
 		Width:  uint16(info.Window.Right - info.Window.Left + 1),
 		Height: uint16(info.Window.Bottom - info.Window.Top + 1),
 		x:      0,
 		y:      0}

 	return winsize, nil
 }

 // IsTerminal returns true if the given file descriptor is a terminal.
 func IsTerminal(fd uintptr) bool {
 	return windows.IsConsole(fd)
 }

 // RestoreTerminal restores the terminal connected to the given file descriptor
 // to a previous state.
 func RestoreTerminal(fd uintptr, state *State) error {
 	if usingNativeConsole {
 		return disableNativeConsole(state)
 	}
 	return winterm.SetConsoleMode(fd, state.outMode)
 }

 // SaveState saves the state of the terminal connected to the given file descriptor.
 func SaveState(fd uintptr) (*State, error) {
 	if usingNativeConsole {
 		state, err := getNativeConsole()
 		if err != nil {
 			return nil, err
 		}
 		return &state, nil
 	}

 	mode, e := winterm.GetConsoleMode(fd)
 	if e != nil {
 		return nil, e
 	}

 	return &State{outMode: mode}, nil
 }

 // DisableEcho disables echo for the terminal connected to the given file descriptor.
 // -- See https://msdn.microsoft.com/en-us/library/windows/desktop/ms683462(v=vs.85).aspx
 func DisableEcho(fd uintptr, state *State) error {
 	mode := state.inMode
 	mode &^= winterm.ENABLE_ECHO_INPUT
 	mode |= winterm.ENABLE_PROCESSED_INPUT | winterm.ENABLE_LINE_INPUT
 	err := winterm.SetConsoleMode(fd, mode)
 	if err != nil {
 		return err
 	}

 	// Register an interrupt handler to catch and restore prior state
 	restoreAtInterrupt(fd, state)
 	return nil
 }

 // SetRawTerminal puts the terminal connected to the given file descriptor into raw
 // mode and returns the previous state.
 func SetRawTerminal(fd uintptr) (*State, error) {
 	state, err := MakeRaw(fd)
 	if err != nil {
 		return nil, err
 	}

 	// Register an interrupt handler to catch and restore prior state
 	restoreAtInterrupt(fd, state)
 	return state, err
 }

 // MakeRaw puts the terminal (Windows Console) connected to the given file descriptor into raw
 // mode and returns the previous state of the terminal so that it can be restored.
 func MakeRaw(fd uintptr) (*State, error) {
 	state, err := SaveState(fd)
 	if err != nil {
 		return nil, err
 	}

 	mode := state.inMode
 	if usingNativeConsole {
 		if err := enableNativeConsole(*state); err != nil {
 			return nil, err
 		}
 		mode |= enableVirtualTerminalInput
 	}

 	// See
 	// -- https://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx
 	// -- https://msdn.microsoft.com/en-us/library/windows/desktop/ms683462(v=vs.85).aspx

 	// Disable these modes
 	mode &^= winterm.ENABLE_ECHO_INPUT
 	mode &^= winterm.ENABLE_LINE_INPUT
 	mode &^= winterm.ENABLE_MOUSE_INPUT
 	mode &^= winterm.ENABLE_WINDOW_INPUT
 	mode &^= winterm.ENABLE_PROCESSED_INPUT

 	// Enable these modes
 	mode |= winterm.ENABLE_EXTENDED_FLAGS
 	mode |= winterm.ENABLE_INSERT_MODE
 	mode |= winterm.ENABLE_QUICK_EDIT_MODE

 	err = winterm.SetConsoleMode(fd, mode)
 	if err != nil {
 		return nil, err
 	}
 	return state, nil
 }

 func restoreAtInterrupt(fd uintptr, state *State) {
 	sigchan := make(chan os.Signal, 1)
 	signal.Notify(sigchan, os.Interrupt)

 	go func() {
 		_ = <-sigchan
 		RestoreTerminal(fd, state)
 		os.Exit(0)
 	}()
 }
	// +build windows

	package term

	import (
	"io"
	"os"
	"os/signal"
	"syscall"

	"github.com/Azure/go-ansiterm/winterm"
	"github.com/docker/docker/pkg/system"
	"github.com/docker/docker/pkg/term/windows"
	)

	// State holds the console mode for the terminal.
	type State struct {
	inMode, outMode uint32
	inHandle, outHandle syscall.Handle
	}

	// Winsize is used for window size.
	type Winsize struct {
	Height uint16
	Width uint16
	x uint16
	y uint16
	}

	const (
	// https://msdn.microsoft.com/en-us/library/windows/desktop/ms683167(v=vs.85).aspx
	enableVirtualTerminalInput = 0x0200
	enableVirtualTerminalProcessing = 0x0004
	)

	// usingNativeConsole is true if we are using the Windows native console
	var usingNativeConsole bool

	// StdStreams returns the standard streams (stdin, stdout, stedrr).
	func StdStreams() (stdIn io.ReadCloser, stdOut, stdErr io.Writer) {
	switch {
	case os.Getenv("ConEmuANSI") == "ON":
	// The ConEmu terminal emulates ANSI on output streams well.
	return windows.ConEmuStreams()
	case os.Getenv("MSYSTEM") != "":
	// MSYS (mingw) does not emulate ANSI well.
	return windows.ConsoleStreams()
	default:
	if useNativeConsole() {
	usingNativeConsole = true
	return os.Stdin, os.Stdout, os.Stderr
	}
	return windows.ConsoleStreams()
	}
	}

	// useNativeConsole determines if the docker client should use the built-in
	// console which supports ANSI emulation, or fall-back to the golang emulator
	// (github.com/azure/go-ansiterm).
	func useNativeConsole() bool {
	osv, err := system.GetOSVersion()
	if err != nil {
	return false
	}

	// Native console is not available before major version 10
	if osv.MajorVersion < 10 {
	return false
	}

	// Must have a late pre-release TP4 build of Windows Server 2016/Windows 10 TH2 or later
	if osv.Build < 10578 {
	return false
	}

	// Get the console modes. If this fails, we can't use the native console
	state, err := getNativeConsole()
	if err != nil {
	return false
	}

	// Probe the console to see if it can be enabled.
	if nil != probeNativeConsole(state) {
	return false
	}

	// Environment variable override
	if e := os.Getenv("USE_NATIVE_CONSOLE"); e != "" {
	if e == "1" {
	return true
	}
	return false
	}

	// TODO Windows. The native emulator still has issues which
	// mean it shouldn't be enabled for everyone. Change this next line to true
	// to change the default to "enable if available". In the meantime, users
	// can still try it out by using USE_NATIVE_CONSOLE env variable.
	return false
	}

	// getNativeConsole returns the console modes ('state') for the native Windows console
	func getNativeConsole() (State, error) {
	var (
	err error
	state State
	)

	// Get the handle to stdout
	if state.outHandle, err = syscall.GetStdHandle(syscall.STD_OUTPUT_HANDLE); err != nil {
	return state, err
	}

	// Get the console mode from the consoles stdout handle
	if err = syscall.GetConsoleMode(state.outHandle, &state.outMode); err != nil {
	return state, err
	}

	// Get the handle to stdin
	if state.inHandle, err = syscall.GetStdHandle(syscall.STD_INPUT_HANDLE); err != nil {
	return state, err
	}

	// Get the console mode from the consoles stdin handle
	if err = syscall.GetConsoleMode(state.inHandle, &state.inMode); err != nil {
	return state, err
	}

	return state, nil
	}

	// probeNativeConsole probes the console to determine if native can be supported,
	func probeNativeConsole(state State) error {
	if err := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode\|enableVirtualTerminalProcessing); err != nil {
	return err
	}
	defer winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode)

	if err := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode\|enableVirtualTerminalInput); err != nil {
	return err
	}
	defer winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode)

	return nil
	}

	// enableNativeConsole turns on native console mode
	func enableNativeConsole(state State) error {
	if err := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode\|enableVirtualTerminalProcessing); err != nil {
	return err
	}

	if err := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode\|enableVirtualTerminalInput); err != nil {
	winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode) // restore out if we can
	return err
	}

	return nil
	}

	// disableNativeConsole turns off native console mode
	func disableNativeConsole(state *State) error {
	// Try and restore both in an out before error checking.
	errout := winterm.SetConsoleMode(uintptr(state.outHandle), state.outMode)
	errin := winterm.SetConsoleMode(uintptr(state.inHandle), state.inMode)
	if errout != nil {
	return errout
	}
	if errin != nil {
	return errin
	}
	return nil
	}

	// GetFdInfo returns the file descriptor for an os.File and indicates whether the file represents a terminal.
	func GetFdInfo(in interface{}) (uintptr, bool) {
	return windows.GetHandleInfo(in)
	}

	// GetWinsize returns the window size based on the specified file descriptor.
	func GetWinsize(fd uintptr) (*Winsize, error) {
	info, err := winterm.GetConsoleScreenBufferInfo(fd)
	if err != nil {
	return nil, err
	}

	winsize := &Winsize{
	Width: uint16(info.Window.Right - info.Window.Left + 1),
	Height: uint16(info.Window.Bottom - info.Window.Top + 1),
	x: 0,
	y: 0}

	return winsize, nil
	}

	// IsTerminal returns true if the given file descriptor is a terminal.
	func IsTerminal(fd uintptr) bool {
	return windows.IsConsole(fd)
	}

	// RestoreTerminal restores the terminal connected to the given file descriptor
	// to a previous state.
	func RestoreTerminal(fd uintptr, state *State) error {
	if usingNativeConsole {
	return disableNativeConsole(state)
	}
	return winterm.SetConsoleMode(fd, state.outMode)
	}

	// SaveState saves the state of the terminal connected to the given file descriptor.
	func SaveState(fd uintptr) (*State, error) {
	if usingNativeConsole {
	state, err := getNativeConsole()
	if err != nil {
	return nil, err
	}
	return &state, nil
	}

	mode, e := winterm.GetConsoleMode(fd)
	if e != nil {
	return nil, e
	}

	return &State{outMode: mode}, nil
	}

	// DisableEcho disables echo for the terminal connected to the given file descriptor.
	// -- See https://msdn.microsoft.com/en-us/library/windows/desktop/ms683462(v=vs.85).aspx
	func DisableEcho(fd uintptr, state *State) error {
	mode := state.inMode
	mode &^= winterm.ENABLE_ECHO_INPUT
	mode \|= winterm.ENABLE_PROCESSED_INPUT \| winterm.ENABLE_LINE_INPUT
	err := winterm.SetConsoleMode(fd, mode)
	if err != nil {
	return err
	}

	// Register an interrupt handler to catch and restore prior state
	restoreAtInterrupt(fd, state)
	return nil
	}

	// SetRawTerminal puts the terminal connected to the given file descriptor into raw
	// mode and returns the previous state.
	func SetRawTerminal(fd uintptr) (*State, error) {
	state, err := MakeRaw(fd)
	if err != nil {
	return nil, err
	}

	// Register an interrupt handler to catch and restore prior state
	restoreAtInterrupt(fd, state)
	return state, err
	}

	// MakeRaw puts the terminal (Windows Console) connected to the given file descriptor into raw
	// mode and returns the previous state of the terminal so that it can be restored.
	func MakeRaw(fd uintptr) (*State, error) {
	state, err := SaveState(fd)
	if err != nil {
	return nil, err
	}

	mode := state.inMode
	if usingNativeConsole {
	if err := enableNativeConsole(*state); err != nil {
	return nil, err
	}
	mode \|= enableVirtualTerminalInput
	}

	// See
	// -- https://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx
	// -- https://msdn.microsoft.com/en-us/library/windows/desktop/ms683462(v=vs.85).aspx

	// Disable these modes
	mode &^= winterm.ENABLE_ECHO_INPUT
	mode &^= winterm.ENABLE_LINE_INPUT
	mode &^= winterm.ENABLE_MOUSE_INPUT
	mode &^= winterm.ENABLE_WINDOW_INPUT
	mode &^= winterm.ENABLE_PROCESSED_INPUT

	// Enable these modes
	mode \|= winterm.ENABLE_EXTENDED_FLAGS
	mode \|= winterm.ENABLE_INSERT_MODE
	mode \|= winterm.ENABLE_QUICK_EDIT_MODE

	err = winterm.SetConsoleMode(fd, mode)
	if err != nil {
	return nil, err
	}
	return state, nil
	}

	func restoreAtInterrupt(fd uintptr, state *State) {
	sigchan := make(chan os.Signal, 1)
	signal.Notify(sigchan, os.Interrupt)

	go func() {
	_ = <-sigchan
	RestoreTerminal(fd, state)
	os.Exit(0)
	}()
	}