Use dconf monitor to keep an eye on show-banner

gnome-dnd.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"log"
+	"os/exec"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"github.com/godbus/dbus/v5"
+)
+
+func monitorGNOMEDND() {
+	go updateDnd()
+	type sigChange struct {
+		prefix	string
+		changes	[]string
+		tag	string
+	}
+	conn, err := dbus.ConnectSessionBus()
+	if err != nil {
+		panic(err)
+	}
+	obj := conn.Object("org.freedesktop.DBus", "/org/freedesktop/DBus")
+	call := obj.Call(
+		"org.freedesktop.DBus.AddMatch",
+		0,
+		"type='signal',path='/ca/desrt/dconf/Writer/user',interface='ca.desrt.dconf.Writer',member='Notify'",
+	)
+	log.Println("Monitoring DnD")
+	if call.Err != nil {
+		log.Fatalln("Could not monitor DND status:", call.Err)
+	}
+	sigChan := make(chan *dbus.Signal, 10)
+	conn.Signal(sigChan)
+
+	for sig := range sigChan {
+		var chg sigChange
+		if sig.Name == "ca.desrt.dconf.Writer.Notify" &&
+		sig.Path == "/ca/desrt/dconf/Writer/user" {
+			err := dbus.Store(sig.Body, &chg.prefix, &chg.changes, &chg.tag)
+			if err != nil {
+				log.Fatalln("Could not store change:", err)
+			}
+			if chg.prefix == "/org/gnome/desktop/notifications/show-banners" {
+				go updateDnd()
+			}
+		}
+	}
+}
+
+func updateDnd() {
+	cmdline := []string{"get", "org.gnome.desktop.notifications", "show-banners"}
+	cmd := exec.Command("gsettings", cmdline...)
+	attr := &syscall.SysProcAttr{
+		Pdeathsig:	syscall.SIGKILL,
+	}
+	cmd.SysProcAttr = attr
+	out, err := cmd.Output()
+	if err != nil {
+		log.Fatalln("Could not get banner state:", err)
+	}
+	output := strings.TrimSuffix(string(out), "\n")
+	boolVal, err := strconv.ParseBool(output)
+	if err != nil {
+		log.Fatalln("Could not get banner state:", err)
+	}
+	dndLock.Lock()
+	soundAllowed = boolVal
+	dndLock.Unlock()
+	log.Println("Updated show-banner status:", boolVal)
+}

go.mod

@@ -2,11 +2,13 @@ module snotify
 
 go 1.26.1
 
-require github.com/godbus/dbus/v5 v5.2.2
+require (
+	github.com/godbus/dbus/v5 v5.2.2
+	github.com/jfreymuth/oggvorbis v1.0.5
+	github.com/jfreymuth/pulse v0.1.1
+)
 
 require (
-	github.com/jfreymuth/oggvorbis v1.0.5 // indirect
-	github.com/jfreymuth/pulse v0.1.1 // indirect
 	github.com/jfreymuth/vorbis v1.0.2 // indirect
 	golang.org/x/sys v0.27.0 // indirect
 )

snotify.go

@@ -1,16 +1,10 @@
 package main
 
 import (
-	"bufio"
 	"errors"
-	"fmt"
 	"log"
 	"os"
-	"os/exec"
-	"strconv"
-	"strings"
 	"sync"
-	"syscall"
 
 	"github.com/godbus/dbus/v5"
 	"github.com/jfreymuth/oggvorbis"
@@ -57,79 +51,7 @@ func dndWatcher() () {
 	env := os.Getenv("XDG_CURRENT_DESKTOP")
 	switch env {
 		case "GNOME":
-			valCmdSlice := []string{
-				"stdbuf",
-				"-oL",
-				"gsettings",
-				"monitor",
-				"org.gnome.desktop.notifications",
-				"show-banners",
-			}
-			getCmdSlice := []string{
-				"gsettings",
-				"get",
-				"org.gnome.desktop.notifications",
-				"show-banners",
-			}
-			cmd := exec.Command(valCmdSlice[0], valCmdSlice[1:]...)
-			attr := syscall.SysProcAttr{
-				Pdeathsig:	syscall.SIGTERM,
-			}
-			cmd.SysProcAttr = &attr
-			var wg sync.WaitGroup
-			wg.Add(1)
-			go func () {
-				pipe, err := cmd.StdoutPipe()
-				wg.Wait()
-				if err != nil {
-					log.Println("GSettings failed:", err)
-					return
-				}
-				scanner := bufio.NewScanner(pipe)
-				cmdGet, err := exec.Command(getCmdSlice[0], getCmdSlice[1:]...).Output()
-				if err != nil {
-					log.Println("GSettings failed:", err)
-					return
-				}
-				line := string(cmdGet)
-				rawVal := strings.TrimSpace(line)
-				log.Println("Allow sound:", rawVal)
-				val, err := strconv.ParseBool(rawVal)
-				if err != nil {
-					log.Println("Could not parse result:", err)
-
-				} else {
-					dndLock.Lock()
-					soundAllowed = val
-					dndLock.Unlock()
-				}
-				for scanner.Scan() {
-					line := scanner.Text()
-					log.Println("Allow status changed:", line)
-					rawVal := strings.TrimPrefix(line, "show-banners:")
-					rawVal = strings.TrimSpace(rawVal)
-					val, err := strconv.ParseBool(rawVal)
-					if err != nil {
-						log.Println("Could not parse result:", err)
-						continue
-					}
-					dndLock.Lock()
-					soundAllowed = val
-					dndLock.Unlock()
-				}
-			} ()
-			wg.Done()
-			err := cmd.Start()
-			if err != nil {
-				fmt.Println("Could not start DnD monitor:", err)
-				return
-			}
-			log.Println("Started DnD watcher")
-			err = cmd.Wait()
-			if err != nil {
-				fmt.Println("GSettings monitor returned error:", err)
-				return
-			}
+			monitorGNOMEDND()
 		default:
 			log.Println("Do not disturb unsupported:", env)
 	}