Add --tty-default=/dev/tty and --no-tty-default option (#4352)

Fix #4242.

Use --no-tty-default, if you want fzf to perform a TTY look-up instead of defaulting to /dev/tty.

man/man1/fzf.1

@@ -228,6 +228,13 @@ e.g. \fB# Avoid rendering both fzf instances at the same time
      (sleep 1; seq 1000000; sleep 1) |
        fzf \-\-sync \-\-query 5 \-\-listen \-\-bind start:up,load:up,result:up,focus:change\-header:Ready\fR
 .RE
+.TP
+.B "\-\-no\-tty\-default"
+Make fzf search for the current TTY device via standard error instead of using
+\fB/dev/tty\fR. This option was added to avoid the problem when trying to open
+emacsclient from within fzf. Alternativly, you can change the default TTY
+device by setting \fB--tty-default=DEVICE_NAME\fR.
+
 .SS GLOBAL STYLE
 .TP
 .BI "\-\-style=" "PRESET"

src/options.go

@@ -631,6 +631,7 @@ type Options struct {
 	MEMProfile        string
 	BlockProfile      string
 	MutexProfile      string
+	TtyDefault        string
 }
 
 func filterNonEmpty(input []string) []string {
@@ -730,6 +731,7 @@ func defaultOptions() *Options {
 		WalkerOpts:   walkerOpts{file: true, hidden: true, follow: true},
 		WalkerRoot:   []string{"."},
 		WalkerSkip:   []string{".git", "node_modules"},
+		TtyDefault:   tui.DefaultTtyDevice,
 		Help:         false,
 		Version:      false}
 }
@@ -2336,6 +2338,12 @@ func parseOptions(index *int, opts *Options, allArgs []string) error {
 			}
 		case "--no-tmux":
 			opts.Tmux = nil
+		case "--tty-default":
+			if opts.TtyDefault, err = nextString("tty device name required"); err != nil {
+				return err
+			}
+		case "--no-tty-default":
+			opts.TtyDefault = ""
 		case "--force-tty-in":
 			// NOTE: We need this because `system('fzf --tmux < /dev/tty')` doesn't
 			// work on Neovim. Same as '-' option of fzf-tmux.

src/proxy.go

@@ -145,7 +145,7 @@ func runProxy(commandPrefix string, cmdBuilder func(temp string, needBash bool)
 					env = elems[1:]
 				}
 				executor := util.NewExecutor(opts.WithShell)
-				ttyin, err := tui.TtyIn()
+				ttyin, err := tui.TtyIn(opts.TtyDefault)
 				if err != nil {
 					return ExitError, err
 				}

src/terminal.go

@@ -381,6 +381,7 @@ type Terminal struct {
 	slab               *util.Slab
 	theme              *tui.ColorTheme
 	tui                tui.Renderer
+	ttyDefault         string
 	ttyin              *os.File
 	executing          *util.AtomicBool
 	termSize           tui.TermSize
@@ -809,7 +810,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor
 	// when you run fzf multiple times in your Go program. Closing it is known to
 	// cause problems with 'become' action and invalid terminal state after exit.
 	if ttyin == nil {
-		if ttyin, err = tui.TtyIn(); err != nil {
+		if ttyin, err = tui.TtyIn(opts.TtyDefault); err != nil {
 			return nil, err
 		}
 	}
@@ -817,7 +818,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor
 		if tui.HasFullscreenRenderer() {
 			renderer = tui.NewFullscreenRenderer(opts.Theme, opts.Black, opts.Mouse)
 		} else {
-			renderer, err = tui.NewLightRenderer(ttyin, opts.Theme, opts.Black, opts.Mouse, opts.Tabstop, opts.ClearOnExit,
+			renderer, err = tui.NewLightRenderer(opts.TtyDefault, ttyin, opts.Theme, opts.Black, opts.Mouse, opts.Tabstop, opts.ClearOnExit,
 				true, func(h int) int { return h })
 		}
 	} else {
@@ -833,7 +834,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor
 			effectiveMinHeight += borderLines(opts.BorderShape)
 			return util.Min(termHeight, util.Max(evaluateHeight(opts, termHeight), effectiveMinHeight))
 		}
-		renderer, err = tui.NewLightRenderer(ttyin, opts.Theme, opts.Black, opts.Mouse, opts.Tabstop, opts.ClearOnExit, false, maxHeightFunc)
+		renderer, err = tui.NewLightRenderer(opts.TtyDefault, ttyin, opts.Theme, opts.Black, opts.Mouse, opts.Tabstop, opts.ClearOnExit, false, maxHeightFunc)
 	}
 	if err != nil {
 		return nil, err
@@ -967,6 +968,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor
 		keyChan:            make(chan tui.Event),
 		eventChan:          make(chan tui.Event, 6), // start | (load + result + zero|one) | (focus) | (resize)
 		tui:                renderer,
+		ttyDefault:         opts.TtyDefault,
 		ttyin:              ttyin,
 		initFunc:           func() error { return renderer.Init() },
 		executing:          util.NewAtomicBool(false),
@@ -4042,7 +4044,7 @@ func (t *Terminal) executeCommand(template string, forcePlus bool, background bo
 	t.executing.Set(true)
 	if !background {
 		// Open a separate handle for tty input
-		if in, _ := tui.TtyIn(); in != nil {
+		if in, _ := tui.TtyIn(t.ttyDefault); in != nil {
 			cmd.Stdin = in
 			if in != os.Stdin {
 				defer in.Close()
@@ -4051,7 +4053,7 @@ func (t *Terminal) executeCommand(template string, forcePlus bool, background bo
 
 		cmd.Stdout = os.Stdout
 		if !util.IsTty(os.Stdout) {
-			if out, _ := tui.TtyOut(); out != nil {
+			if out, _ := tui.TtyOut(t.ttyDefault); out != nil {
 				cmd.Stdout = out
 				defer out.Close()
 			}
@@ -4059,7 +4061,7 @@ func (t *Terminal) executeCommand(template string, forcePlus bool, background bo
 
 		cmd.Stderr = os.Stderr
 		if !util.IsTty(os.Stderr) {
-			if out, _ := tui.TtyOut(); out != nil {
+			if out, _ := tui.TtyOut(t.ttyDefault); out != nil {
 				cmd.Stderr = out
 				defer out.Close()
 			}

src/tui/light.go

@@ -28,7 +28,7 @@ const (
 	maxInputBuffer  = 1024 * 1024
 )
 
-const consoleDevice string = "/dev/tty"
+const DefaultTtyDevice string = "/dev/tty"
 
 var offsetRegexp = regexp.MustCompile("(.*?)\x00?\x1b\\[([0-9]+);([0-9]+)R")
 var offsetRegexpBegin = regexp.MustCompile("^\x1b\\[[0-9]+;[0-9]+R")
@@ -146,8 +146,8 @@ type LightWindow struct {
 	wrapSignWidth int
 }
 
-func NewLightRenderer(ttyin *os.File, theme *ColorTheme, forceBlack bool, mouse bool, tabstop int, clearOnExit bool, fullscreen bool, maxHeightFunc func(int) int) (Renderer, error) {
-	out, err := openTtyOut()
+func NewLightRenderer(ttyDefault string, ttyin *os.File, theme *ColorTheme, forceBlack bool, mouse bool, tabstop int, clearOnExit bool, fullscreen bool, maxHeightFunc func(int) int) (Renderer, error) {
+	out, err := openTtyOut(ttyDefault)
 	if err != nil {
 		out = os.Stderr
 	}
@@ -271,7 +271,7 @@ func (r *LightRenderer) getBytesInternal(buffer []byte, nonblock bool) ([]byte,
 	c, ok := r.getch(nonblock)
 	if !nonblock && !ok {
 		r.Close()
-		return nil, errors.New("failed to read " + consoleDevice)
+		return nil, errors.New("failed to read " + DefaultTtyDevice)
 	}
 
 	retries := 0

src/tui/light_unix.go

@@ -42,26 +42,35 @@ func (r *LightRenderer) closePlatform() {
 	r.ttyout.Close()
 }
 
-func openTty(mode int) (*os.File, error) {
-	in, err := os.OpenFile(consoleDevice, mode, 0)
-	if err != nil {
+func openTty(ttyDefault string, mode int) (*os.File, error) {
+	var in *os.File
+	var err error
+	if len(ttyDefault) > 0 {
+		in, err = os.OpenFile(ttyDefault, mode, 0)
+	}
+	if in == nil || err != nil || ttyDefault != DefaultTtyDevice && !util.IsTty(in) {
 		tty := ttyname()
 		if len(tty) > 0 {
 			if in, err := os.OpenFile(tty, mode, 0); err == nil {
 				return in, nil
 			}
 		}
-		return nil, errors.New("failed to open " + consoleDevice)
+		if ttyDefault != DefaultTtyDevice {
+			if in, err = os.OpenFile(DefaultTtyDevice, mode, 0); err == nil {
+				return in, nil
+			}
+		}
+		return nil, errors.New("failed to open " + DefaultTtyDevice)
 	}
 	return in, nil
 }
 
-func openTtyIn() (*os.File, error) {
-	return openTty(syscall.O_RDONLY)
+func openTtyIn(ttyDefault string) (*os.File, error) {
+	return openTty(ttyDefault, syscall.O_RDONLY)
 }
 
-func openTtyOut() (*os.File, error) {
-	return openTty(syscall.O_WRONLY)
+func openTtyOut(ttyDefault string) (*os.File, error) {
+	return openTty(ttyDefault, syscall.O_WRONLY)
 }
 
 func (r *LightRenderer) setupTerminal() {

src/tui/light_windows.go

@@ -76,12 +76,12 @@ func (r *LightRenderer) closePlatform() {
 	windows.SetConsoleMode(windows.Handle(r.inHandle), r.origStateInput)
 }
 
-func openTtyIn() (*os.File, error) {
+func openTtyIn(ttyDefault string) (*os.File, error) {
 	// not used
 	return nil, nil
 }
 
-func openTtyOut() (*os.File, error) {
+func openTtyOut(ttyDefault string) (*os.File, error) {
 	return os.Stderr, nil
 }
 

src/tui/ttyname_unix.go

@@ -44,11 +44,11 @@ func ttyname() string {
 }
 
 // TtyIn returns terminal device to read user input
-func TtyIn() (*os.File, error) {
-	return openTtyIn()
+func TtyIn(ttyDefault string) (*os.File, error) {
+	return openTtyIn(ttyDefault)
 }
 
 // TtyIn returns terminal device to write to
-func TtyOut() (*os.File, error) {
-	return openTtyOut()
+func TtyOut(ttyDefault string) (*os.File, error) {
+	return openTtyOut(ttyDefault)
 }

src/tui/ttyname_windows.go

@@ -11,11 +11,11 @@ func ttyname() string {
 }
 
 // TtyIn on Windows returns os.Stdin
-func TtyIn() (*os.File, error) {
+func TtyIn(ttyDefault string) (*os.File, error) {
 	return os.Stdin, nil
 }
 
 // TtyOut on Windows returns nil
-func TtyOut() (*os.File, error) {
+func TtyOut(ttyDefault string) (*os.File, error) {
 	return nil, nil
 }