Notification listen.

cmd/zenity/main.go

@@ -47,11 +47,11 @@ var (
 	text          string
 	icon          string
 	multiple      bool
+	defaultCancel bool
 
 	// Message options
 	noWrap    bool
 	ellipsize bool
-	defaultCancel bool
 
 	// Entry options
 	entryText string
@@ -81,6 +81,9 @@ var (
 	autoKill   bool
 	noCancel   bool
 
+	// Notify options
+	listen bool
+
 	// Windows specific options
 	unixeol bool
 	cygpath bool
@@ -151,7 +154,7 @@ func main() {
 		errResult(progress(opts...))
 
 	case notification:
-		errResult(zenity.Notify(text, opts...))
+		errResult(notify(opts...))
 
 	default:
 		flag.Usage()
@@ -220,6 +223,9 @@ func setupFlags() {
 		flag.BoolVar(&autoKill, "auto-kill", false, "Kill parent process if Cancel button is pressed (macOS and Unix only)")
 	}
 
+	// Notify options
+	flag.BoolVar(&listen, "listen", false, "Listen for commands on stdin")
+
 	// Windows specific options
 	if runtime.GOOS == "windows" {
 		flag.BoolVar(&unixeol, "unixeol", false, "Use Unix line endings (Windows only)")
@@ -332,6 +338,8 @@ func loadFlags() []zenity.Option {
 		setDefault(&text, "Running...")
 		setDefault(&okLabel, "OK")
 		setDefault(&cancelLabel, "Cancel")
+	case notification:
+		setDefault(&icon, "dialog-information")
 	default:
 		setDefault(&text, "")
 	}

cmd/zenity/notify.go

@@ -0,0 +1,61 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/ncruces/zenity"
+	"github.com/ncruces/zenity/internal/zenutil"
+)
+
+func notify(opts ...zenity.Option) error {
+	if !listen {
+		return zenity.Notify(text, opts...)
+	}
+
+	zenutil.Command = false
+	var icon zenity.DialogIcon
+	for scanner := bufio.NewScanner(os.Stdin); scanner.Scan(); {
+		line := scanner.Text()
+		var cmd, msg string
+		if n := strings.IndexByte(line, ':'); n >= 0 {
+			cmd = strings.TrimSpace(line[:n])
+			msg = strings.TrimSpace(zenutil.Unescape(line[n+1:]))
+		} else {
+			fmt.Fprint(os.Stderr, "Could not parse command from stdin")
+		}
+		switch cmd {
+		case "icon":
+			switch msg {
+			case "error", "dialog-error":
+				icon = zenity.ErrorIcon
+			case "info", "dialog-information":
+				icon = zenity.InfoIcon
+			case "question", "dialog-question":
+				icon = zenity.QuestionIcon
+			case "important", "warning", "dialog-warning":
+				icon = zenity.WarningIcon
+			case "dialog-password":
+				icon = zenity.PasswordIcon
+			default:
+				icon = zenity.NoIcon
+			}
+		case "message", "tooltip":
+			opts := []zenity.Option{zenity.Icon(icon)}
+			if n := strings.IndexByte(msg, '\n'); n >= 0 {
+				opts = append(opts, zenity.Title(msg[:n]))
+				msg = msg[n+1:]
+			}
+			if err := zenity.Notify(msg, opts...); err != nil {
+				return err
+			}
+		case "visible", "hints":
+			// ignored
+		default:
+			fmt.Fprintf(os.Stderr, "Unknown command %q", cmd)
+		}
+	}
+	return nil
+}

internal/zenutil/unescape.go

@@ -0,0 +1,89 @@
+package zenutil
+
+// Unescape is internal.
+func Unescape(s string) string {
+	// Apply rules described in:
+	// https://developer.gnome.org/glib/stable/glib-String-Utility-Functions.html#g-strescape
+
+	const (
+		initial = iota
+		escape1
+		escape2
+		escape3
+	)
+	var oct byte
+	var res []byte
+	state := initial
+	for _, b := range []byte(s) {
+		switch state {
+		case initial:
+			switch b {
+			case '\\':
+				state = escape1
+			default:
+				res = append(res, b)
+				state = initial
+			}
+
+		case escape1:
+			switch b {
+			case '0', '1', '2', '3', '4', '5', '6', '7':
+				oct = b - '0'
+				state = escape2
+			case 'b':
+				res = append(res, '\b')
+				state = initial
+			case 'f':
+				res = append(res, '\f')
+				state = initial
+			case 'n':
+				res = append(res, '\n')
+				state = initial
+			case 'r':
+				res = append(res, '\r')
+				state = initial
+			case 't':
+				res = append(res, '\t')
+				state = initial
+			case 'v':
+				res = append(res, '\v')
+				state = initial
+			default:
+				res = append(res, b)
+				state = initial
+			}
+
+		case escape2:
+			switch b {
+			case '0', '1', '2', '3', '4', '5', '6', '7':
+				oct = oct<<3 | (b - '0')
+				state = escape3
+			case '\\':
+				res = append(res, oct)
+				state = escape1
+			default:
+				res = append(res, oct, b)
+				state = initial
+			}
+
+		case escape3:
+			switch b {
+			case '0', '1', '2', '3', '4', '5', '6', '7':
+				oct = oct<<3 | (b - '0')
+				res = append(res, oct)
+				state = initial
+			case '\\':
+				res = append(res, oct)
+				state = escape1
+			default:
+				res = append(res, oct, b)
+				state = initial
+			}
+		}
+	}
+	if state == escape2 || state == escape3 {
+		res = append(res, oct)
+	}
+
+	return string(res)
+}

internal/zenutil/unescape_test.go

@@ -0,0 +1,28 @@
+package zenutil
+
+import "testing"
+
+func TestUnescape(t *testing.T) {
+	tests := []struct {
+		data string
+		want string
+	}{
+		{`abc`, "abc"},
+		{`ab\c`, "abc"},
+		{`a\bc`, "a\bc"},
+		{`a\1c`, "a\001c"},
+		{`a\12c`, "a\012c"},
+		{`a\123c`, "a\123c"},
+		{`a\1\b`, "a\001\b"},
+		{`a\12\b`, "a\012\b"},
+		{`a\123\b`, "a\123\b"},
+		{`abc\1`, "abc\001"},
+		{`abc\12`, "abc\012"},
+		{`abc\123`, "abc\123"},
+	}
+	for _, tt := range tests {
+		if got := Unescape(tt.data); got != tt.want {
+			t.Errorf("Unescape(%q) = %q, want %q", tt.data, got, tt.want)
+		}
+	}
+}

zenity.go

@@ -38,17 +38,17 @@ type options struct {
 	cancelLabel   *string
 	extraButton   *string
 	icon          DialogIcon
+	defaultCancel bool
+
+	// Message options
+	noWrap    bool
+	ellipsize bool
 
 	// Entry options
 	entryText string
 	hideText  bool
 	username  bool
 
-	// Message options
-	noWrap        bool
-	ellipsize     bool
-	defaultCancel bool
-
 	// List options
 	disallowEmpty bool
 	defaultItems  []string