Use Event for screensaver inhibit state

src/freedesktop_screensaver.rs

@@ -7,6 +7,8 @@ use std::sync::{
     Arc, Mutex,
 };
 
+use crate::{Event, EventSender};
+
 #[derive(Debug)]
 pub struct Inhibitor {
     cookie: u32,
@@ -18,6 +20,7 @@ pub struct Inhibitor {
 pub struct Screensaver {
     inhibitors: Arc<Mutex<Vec<Inhibitor>>>,
     last_cookie: AtomicU32,
+    event_sender: EventSender,
 }
 
 #[zbus::interface(name = "org.freedesktop.ScreenSaver")]
@@ -37,7 +40,11 @@ impl Screensaver {
                 reason_for_inhibit,
                 cookie
             );
-            self.inhibitors.lock().unwrap().push(Inhibitor {
+            let mut inhibitors = self.inhibitors.lock().unwrap();
+            if inhibitors.is_empty() {
+                let _ = self.event_sender.send(Event::ScreensaverInhibit(false));
+            }
+            inhibitors.push(Inhibitor {
                 cookie,
                 application_name,
                 reason_for_inhibit,
@@ -62,10 +69,9 @@ impl Screensaver {
     }
 }
 
-pub async fn serve(
-    conn: &zbus::Connection,
-    inhibitors: Arc<Mutex<Vec<Inhibitor>>>,
-) -> zbus::Result<()> {
+pub async fn serve(conn: &zbus::Connection, event_sender: EventSender) -> zbus::Result<()> {
+    let inhibitors = Arc::new(Mutex::new(Vec::new()));
+
     conn.request_name_with_flags(
         "org.freedesktop.ScreenSaver",
         zbus::fdo::RequestNameFlags::ReplaceExisting.into(),
@@ -76,6 +82,7 @@ pub async fn serve(
             "/org/freedesktop/ScreenSaver",
             Screensaver {
                 inhibitors: inhibitors.clone(),
+                event_sender: event_sender.clone(),
                 last_cookie: AtomicU32::new(0),
             },
         )
@@ -87,10 +94,13 @@ pub async fn serve(
         let args = event.args()?;
         if args.new_owner.is_none() {
             if let zbus::names::BusName::Unique(name) = args.name {
-                inhibitors
-                    .lock()
-                    .unwrap()
-                    .retain(|inhibitor| inhibitor.client != name);
+                let mut inhibitors = inhibitors.lock().unwrap();
+                if !inhibitors.is_empty() {
+                    inhibitors.retain(|inhibitor| inhibitor.client != name);
+                    if inhibitors.is_empty() {
+                        let _ = event_sender.send(Event::ScreensaverInhibit(false));
+                    }
+                }
             }
         }
     }

src/main.rs

@@ -5,10 +5,7 @@ use calloop_wayland_source::WaylandSource;
 use cosmic_config::{calloop::ConfigWatchSource, CosmicConfigEntry};
 use cosmic_idle_config::CosmicIdleConfig;
 use futures_lite::stream::StreamExt;
-use std::{
-    process::Command,
-    sync::{Arc, Mutex},
-};
+use std::process::Command;
 use upower_dbus::UPowerProxy;
 use wayland_client::{
     delegate_noop,
@@ -35,8 +32,11 @@ mod freedesktop_screensaver;
 #[derive(Debug)]
 enum Event {
     OnBattery(bool),
+    ScreensaverInhibit(bool),
 }
 
+type EventSender = channel::Sender<Event>;
+
 struct IdleNotification {
     notification: ext_idle_notification_v1::ExtIdleNotificationV1,
     time: u32,
@@ -58,7 +58,7 @@ impl Drop for IdleNotification {
     }
 }
 
-async fn receive_battery_task(sender: channel::Sender<Event>) -> zbus::Result<()> {
+async fn receive_battery_task(sender: EventSender) -> zbus::Result<()> {
     let connection = zbus::Connection::system().await?;
     let upower = UPowerProxy::new(&connection).await?;
     let mut stream = upower.receive_on_battery_changed().await;
@@ -95,12 +95,12 @@ struct State {
     screen_off_idle_notification: Option<IdleNotification>,
     suspend_idle_notification: Option<IdleNotification>,
     on_battery: bool,
-    screensaver_inhibitors: Arc<Mutex<Vec<freedesktop_screensaver::Inhibitor>>>,
+    screensaver_inhibit: bool,
 }
 
 impl State {
     fn update_screen_off_idle(&mut self, is_idle: bool) {
-        if !self.screensaver_inhibitors.lock().unwrap().is_empty() {
+        if self.screensaver_inhibit {
             return;
         }
         for output in &mut self.outputs {
@@ -114,7 +114,7 @@ impl State {
     }
 
     fn update_suspend_idle(&mut self, is_idle: bool) {
-        if !self.screensaver_inhibitors.lock().unwrap().is_empty() {
+        if self.screensaver_inhibit {
             return;
         }
         if is_idle {
@@ -154,6 +154,9 @@ impl State {
             Event::OnBattery(value) => {
                 self.on_battery = value;
             }
+            Event::ScreensaverInhibit(value) => {
+                self.screensaver_inhibit = value;
+            }
         }
     }
 }
@@ -224,8 +227,6 @@ fn main() {
         conf
     });
 
-    let screensaver_inhibitors = Arc::new(Mutex::new(Vec::new()));
-
     let mut state = State {
         inner: StateInner {
             compositor,
@@ -242,7 +243,7 @@ fn main() {
         outputs,
         conf,
         on_battery: false,
-        screensaver_inhibitors: screensaver_inhibitors.clone(),
+        screensaver_inhibit: false,
     };
     state.recreate_notification();
 
@@ -264,9 +265,10 @@ fn main() {
 
     let (executor, scheduler) = calloop::futures::executor().unwrap();
     let (sender, receiver) = channel::channel();
+    let sender_clone = sender.clone();
     scheduler
         .schedule(async move {
-            if let Err(err) = receive_battery_task(sender).await {
+            if let Err(err) = receive_battery_task(sender_clone).await {
                 log::error!("Getting battery status from upower: {}", err);
             }
         })
@@ -274,9 +276,7 @@ fn main() {
     scheduler
         .schedule(async move {
             if let Ok(connection) = zbus::Connection::session().await {
-                if let Err(err) =
-                    freedesktop_screensaver::serve(&connection, screensaver_inhibitors).await
-                {
+                if let Err(err) = freedesktop_screensaver::serve(&connection, sender).await {
                     log::error!("failed to serve FreeDesktop screensaver interface: {}", err);
                 }
             }