package term import ( "io" "os" "os/signal" windowsconsole "github.com/moby/term/windows" "golang.org/x/sys/windows" ) // State holds the console mode for the terminal. type State struct { mode uint32 } // Winsize is used for window size. type Winsize struct { Height uint16 Width uint16 } // vtInputSupported is true if winterm.ENABLE_VIRTUAL_TERMINAL_INPUT is supported by the console var vtInputSupported bool // StdStreams returns the standard streams (stdin, stdout, stderr). func StdStreams() (stdIn io.ReadCloser, stdOut, stdErr io.Writer) { // Turn on VT handling on all std handles, if possible. This might // fail, in which case we will fall back to terminal emulation. var ( emulateStdin, emulateStdout, emulateStderr bool mode uint32 ) fd := windows.Handle(os.Stdin.Fd()) if err := windows.GetConsoleMode(fd, &mode); err == nil { // Validate that winterm.ENABLE_VIRTUAL_TERMINAL_INPUT is supported, but do not set it. if err = windows.SetConsoleMode(fd, mode|windows.ENABLE_VIRTUAL_TERMINAL_INPUT); err != nil { emulateStdin = true } else { vtInputSupported = true } // Unconditionally set the console mode back even on failure because SetConsoleMode // remembers invalid bits on input handles. _ = windows.SetConsoleMode(fd, mode) } fd = windows.Handle(os.Stdout.Fd()) if err := windows.GetConsoleMode(fd, &mode); err == nil { // Validate winterm.DISABLE_NEWLINE_AUTO_RETURN is supported, but do not set it. if err = windows.SetConsoleMode(fd, mode|windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING|windows.DISABLE_NEWLINE_AUTO_RETURN); err != nil { emulateStdout = true } else { _ = windows.SetConsoleMode(fd, mode|windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING) } } fd = windows.Handle(os.Stderr.Fd()) if err := windows.GetConsoleMode(fd, &mode); err == nil { // Validate winterm.DISABLE_NEWLINE_AUTO_RETURN is supported, but do not set it. if err = windows.SetConsoleMode(fd, mode|windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING|windows.DISABLE_NEWLINE_AUTO_RETURN); err != nil { emulateStderr = true } else { _ = windows.SetConsoleMode(fd, mode|windows.ENABLE_VIRTUAL_TERMINAL_PROCESSING) } } if emulateStdin { h := uint32(windows.STD_INPUT_HANDLE) stdIn = windowsconsole.NewAnsiReader(int(h)) } else { stdIn = os.Stdin } if emulateStdout { h := uint32(windows.STD_OUTPUT_HANDLE) stdOut = windowsconsole.NewAnsiWriter(int(h)) } else { stdOut = os.Stdout } if emulateStderr { h := uint32(windows.STD_ERROR_HANDLE) stdErr = windowsconsole.NewAnsiWriter(int(h)) } else { stdErr = os.Stderr } return } // GetFdInfo returns the file descriptor for an os.File and indicates whether the file represents a terminal. func GetFdInfo(in interface{}) (uintptr, bool) { return windowsconsole.GetHandleInfo(in) } // GetWinsize returns the window size based on the specified file descriptor. func GetWinsize(fd uintptr) (*Winsize, error) { var info windows.ConsoleScreenBufferInfo if err := windows.GetConsoleScreenBufferInfo(windows.Handle(fd), &info); 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), } return winsize, nil } // IsTerminal returns true if the given file descriptor is a terminal. func IsTerminal(fd uintptr) bool { var mode uint32 err := windows.GetConsoleMode(windows.Handle(fd), &mode) return err == nil } // RestoreTerminal restores the terminal connected to the given file descriptor // to a previous state. func RestoreTerminal(fd uintptr, state *State) error { return windows.SetConsoleMode(windows.Handle(fd), state.mode) } // SaveState saves the state of the terminal connected to the given file descriptor. func SaveState(fd uintptr) (*State, error) { var mode uint32 if err := windows.GetConsoleMode(windows.Handle(fd), &mode); err != nil { return nil, err } return &State{mode: 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.mode mode &^= windows.ENABLE_ECHO_INPUT mode |= windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT err := windows.SetConsoleMode(windows.Handle(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. On UNIX, this puts both the input // and output into raw mode. On Windows, it only puts the input into raw mode. 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 } // SetRawTerminalOutput puts the output of terminal connected to the given file // descriptor into raw mode. On UNIX, this does nothing and returns nil for the // state. On Windows, it disables LF -> CRLF translation. func SetRawTerminalOutput(fd uintptr) (*State, error) { state, err := SaveState(fd) if err != nil { return nil, err } // Ignore failures, since winterm.DISABLE_NEWLINE_AUTO_RETURN might not be supported on this // version of Windows. _ = windows.SetConsoleMode(windows.Handle(fd), state.mode|windows.DISABLE_NEWLINE_AUTO_RETURN) 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.mode // 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 &^= windows.ENABLE_ECHO_INPUT mode &^= windows.ENABLE_LINE_INPUT mode &^= windows.ENABLE_MOUSE_INPUT mode &^= windows.ENABLE_WINDOW_INPUT mode &^= windows.ENABLE_PROCESSED_INPUT // Enable these modes mode |= windows.ENABLE_EXTENDED_FLAGS mode |= windows.ENABLE_INSERT_MODE mode |= windows.ENABLE_QUICK_EDIT_MODE if vtInputSupported { mode |= windows.ENABLE_VIRTUAL_TERMINAL_INPUT } err = windows.SetConsoleMode(windows.Handle(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) }() }