Initial commit

vendor/github.com/hyperhq/hypercli/pkg/term/term_windows.go

@@ -0,0 +1,305 @@
+// +build windows
+
+package term
+
+import (
+	"io"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/Azure/go-ansiterm/winterm"
+	"github.com/hyperhq/hypercli/pkg/system"
+	"github.com/hyperhq/hypercli/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)
+	}()
+}