feat: Initial implementation

Cargo.toml

@@ -3,11 +3,18 @@ name = "lungo"
 version = "0.0.1"
 authors = ["Robin Candau <robincandau@protonmail.com>"]
 edition = "2024"
-description = "A simple systray applet to prevent your system from going idle or sleeping on demand"
+description = "A simple systray applet to prevent the system from going idle or suspending on demand"
 license = "GPL-3.0-or-later"
 
 [dependencies]
 clap = { version = "4.6.1", features = ["derive"] }
+dirs = "6.0.0"
+env_logger = "0.11.11"
+fs2 = "0.4.3"
+ksni = "0.3.6"
+log = "0.4.33"
+tokio = "1.53.1"
+zbus = "5.18.0"
 
 [dev-dependencies]
 assert_cmd = "2.0.0"

README.md

@@ -11,12 +11,13 @@
 
 ## Description
 
-A simple systray applet to prevent your system from going idle or sleeping on demand.
+A simple systray applet to prevent the system from going idle or suspending on demand (including on laptop lid closure).
 
 Run `lungo` to start the systray applet.
 
 Simply click on the systray applet to toggle it on and off.  
-The systray icon automatically changes to reflect the current state ("empty cup" icon if off, "hot cup" icon if on).
+The systray icon automatically changes to reflect the current state ("empty cup" icon if off, "hot cup" icon if on).  
+The state can also be consulted and toggled from the systray applet menu.
 
 Lungo is:
 
@@ -69,7 +70,9 @@ cd lungo
 cargo build --release
 ```
 
-The built binary will be located at `./target/release/lungo`.
+The built binary will be located at `./target/release/lungo`, place it somewhere in your `$PATH`.
+
+Place the icons from the [`res/icons/`](https://github.com/Antiz96/lungo/tree/main/res/icons) directory in an "icon compliant" folder on the system (such as `~/.icons/lungo/`, `~/.local/share/icons/lungo` or `/usr/share/icons/lungo/`, create it if needed). For packaging, using the `hicolor-icon-theme` folder (e.g. `/usr/share/icons/hicolor/scalable/apps/`) is an option.
 
 A `.desktop` file is available in the [`res/desktop/`](https://github.com/Antiz96/lungo/tree/main/res/desktop) directory, allowing to automatically start the systray applet at boot via [XDG Autostart](https://wiki.archlinux.org/title/XDG_Autostart) (by placing it either in `~/.config/autostart/` or `/etc/xdg/autostart/`).
 
@@ -88,7 +91,8 @@ Run `lungo` to start the systray applet.
 To start it automatically at boot, either place the [`.desktop file`](https://github.com/Antiz96/lungo/blob/main/res/desktop/lungo.desktop) in `~/.config/autostart/` or `/etc/xdg/autostart/` (relies on [XDG Autostart](https://wiki.archlinux.org/title/XDG_Autostart)). Alternatively (if your graphical environment doesn't support XDG Autostart for instance), add the `lungo` command to your environment's auto-start method.
 
 Simply click on the systray applet to toggle it on and off.  
-The icon automatically changes to reflect the current state ("empty cup" icon if off, "hot cup" icon if on).
+The icon automatically changes to reflect the current state ("empty cup" icon if off, "hot cup" icon if on).  
+The state can also be consulted and toggled from the systray applet menu.
 
 ## Documentation
 

doc/man/lungo.1.scd

@@ -2,14 +2,15 @@ lungo(1) ["Lungo 0.0.1" ["Lungo Manual"]]
 
 # NAME
 
-Lungo - A simple systray applet to prevent your system from going idle or sleeping on demand.
+Lungo - A simple systray applet to prevent the system from going idle or suspending on demand (including on laptop lid closure).
 
 # DESCRIPTION
 
 Run `lungo` to start the systray applet.
 
 Simply click on the systray applet to toggle it on and off.
 The icon automatically changes to reflect the current state ("empty cup" icon if off, "hot cup" icon if on).
+The state can also be consulted and toggled from the systray applet menu.
 
 # SYNOPSIS
 

res/desktop/lungo.desktop

@@ -1,6 +1,6 @@
 [Desktop Entry]
 Name=Lungo
-Comment=A simple systray applet to prevent your system from going idle or sleeping on demand
+Comment=A simple systray applet to prevent the system from going idle or suspending on demand
 Icon=lungo
 Type=Application
 Exec=lungo

src/help.rs

@@ -2,7 +2,7 @@
 
 pub fn show_help() {
     println!(
-        "Lungo - A simple systray applet to prevent your system from going idle or sleeping on demand."
+        "Lungo - A simple systray applet to prevent the system from going idle or suspending on demand (including on laptop lid closure)."
     );
     println!();
     println!("Run `lungo` to start the systray applet.");
@@ -11,6 +11,7 @@ pub fn show_help() {
     println!(
         "The icon automatically changes to reflect the current state (\"empty cup\" icon if off, \"hot cup\" icon if on)."
     );
+    println!("The state can also be consulted and toggled from the systray applet menu.");
     println!();
     println!("Options:");
     println!("  -h, --help     Display this message");

src/inhibit.rs

@@ -0,0 +1,27 @@
+//! Acquire inhibit file descriptor lock through logind
+
+use std::os::fd::OwnedFd;
+use zbus::blocking::Connection;
+use zbus::zvariant::OwnedFd as ZbusFd;
+
+pub fn acquire_inhibit() -> Result<OwnedFd, Box<dyn std::error::Error>> {
+    let conn = Connection::system()?;
+
+    let reply: ZbusFd = conn
+        .call_method(
+            Some("org.freedesktop.login1"),
+            "/org/freedesktop/login1",
+            Some("org.freedesktop.login1.Manager"),
+            "Inhibit",
+            &(
+                "idle:sleep:handle-lid-switch",
+                "Lungo",
+                "Keeping the system awake",
+                "block",
+            ),
+        )?
+        .body()
+        .deserialize()?;
+
+    Ok(reply.into())
+}

src/lockfile.rs

@@ -0,0 +1,32 @@
+//! Create (if needed) and acquire lockfile
+//! in order to prevent multiple instances to run at the same time
+
+use fs2::FileExt;
+use std::fs::{self, File, OpenOptions};
+use std::io::{self, Error, ErrorKind};
+
+pub fn acquire_lockfile() -> io::Result<File> {
+    // Create lungo cachedir (if it doesn't exist)
+    let cachedir = dirs::cache_dir()
+        .ok_or_else(|| Error::new(ErrorKind::NotFound, "Could not determine cache directory"))?
+        .join("lungo");
+    fs::create_dir_all(&cachedir)?;
+
+    let lockfile_path = cachedir.join("lungo.lock");
+
+    let lockfile = OpenOptions::new()
+        .create(true)
+        .write(true)
+        .truncate(false)
+        .open(lockfile_path)?;
+
+    lockfile.try_lock_exclusive().map_err(|error| {
+        if error.kind() == ErrorKind::WouldBlock {
+            Error::from(ErrorKind::AlreadyExists)
+        } else {
+            error
+        }
+    })?;
+
+    Ok(lockfile)
+}

src/main.rs

@@ -1,8 +1,14 @@
-//! Lungo - A simple systray applet to prevent your system from going idle or sleeping on demand.
+//! Lungo - A simple systray applet to prevent the system from going idle or suspending on demand (including on laptop lid closure).
 
 use clap::Parser;
+use log::error;
+use std::io::ErrorKind;
+use std::process;
 
 mod help;
+mod inhibit;
+mod lockfile;
+mod tray;
 mod version;
 
 // Argument parser
@@ -17,7 +23,11 @@ struct Args {
     version: bool,
 }
 
-fn main() {
+#[tokio::main]
+async fn main() {
+    // Initialize logger
+    env_logger::init();
+
     // Parse arguments
     let args = Args::parse();
 
@@ -30,6 +40,22 @@ fn main() {
     // Show name and version if the -V / --version arg is passed
     if args.version {
         version::show_version();
-        //return;
+        return;
     }
+
+    // Create (if needed) and acquire lockfile
+    // Exit if there's already an instance running
+    // or if there was an issue creating or acquiring the lockfile (e.g. permission issue)
+    let _lock = lockfile::acquire_lockfile().unwrap_or_else(|error| {
+        if error.kind() == ErrorKind::AlreadyExists {
+            error!("Another instance of lungo is already running");
+        } else {
+            error!("Failed to acquire lockfile: {error}");
+        }
+
+        process::exit(1);
+    });
+
+    // Start systray applet
+    tray::run().await;
 }

src/tray.rs

@@ -0,0 +1,115 @@
+//! Systray applet implementation
+//! Built with ksni:
+//! https://github.com/iovxw/ksni
+//! https://crates.io/crates/ksni
+
+use ksni::TrayMethods;
+use ksni::menu::*;
+use log::{debug, info};
+use std::future;
+use std::os::fd::OwnedFd;
+use std::process;
+use tokio::task;
+
+use crate::inhibit;
+
+pub struct LungoTray {
+    inhibit_fd: Option<OwnedFd>,
+}
+
+// Systray Applet implementation
+impl ksni::Tray for LungoTray {
+    // Set id
+    fn id(&self) -> String {
+        "Lungo".into()
+    }
+
+    // Set icon
+    fn icon_name(&self) -> String {
+        let icon = if self.inhibit_fd.is_some() {
+            "lungo-on"
+        } else {
+            "lungo-off"
+        };
+
+        debug!("Icon set or updated: {icon}");
+        icon.into()
+    }
+
+    // Set title
+    fn title(&self) -> String {
+        "Lungo".into()
+    }
+
+    // Set tooltip
+    fn tool_tip(&self) -> ksni::ToolTip {
+        ksni::ToolTip {
+            title: "Lungo".into(),
+            ..Default::default()
+        }
+    }
+
+    // Toggle checkable menu entry on click (triggers inhibitor lock and changes icon accordingly)
+    fn activate(&mut self, _x: i32, _y: i32) {
+        self.toggle();
+    }
+
+    // Build menu
+    fn menu(&self) -> Vec<ksni::MenuItem<Self>> {
+        vec![
+            // Checkable menu entry, reporting the current state and allowing to toggle the creation
+            // or release of the inhibit file descriptor lock
+            CheckmarkItem {
+                label: "Enable".into(),
+                checked: self.inhibit_fd.is_some(),
+                activate: Box::new(|this: &mut Self| this.toggle()),
+                ..Default::default()
+            }
+            .into(),
+            // Exit button
+            StandardItem {
+                label: "Exit".into(),
+                activate: Box::new(|_| {
+                    info!("Exited on user request");
+                    process::exit(0);
+                }),
+                ..Default::default()
+            }
+            .into(),
+        ]
+    }
+}
+
+// Helper to toggle the creation and releasing of the inhibit file descriptor lock
+impl LungoTray {
+    fn toggle(&mut self) {
+        if self.inhibit_fd.is_some() {
+            self.inhibit_fd = None;
+            info!("Inhibitor disabled");
+        } else {
+            match task::block_in_place(inhibit::acquire_inhibit) {
+                Ok(fd) => {
+                    self.inhibit_fd = Some(fd);
+                    info!("Inhibitor enabled");
+                }
+                Err(error) => {
+                    log::error!("Unable to acquire inhibitor: {error}");
+                }
+            }
+        }
+    }
+}
+
+// Starting the Systray Applet
+pub async fn run() {
+    let tray = LungoTray { inhibit_fd: None };
+
+    tray.spawn()
+        .await
+        .expect("Unable to start the systray applet");
+
+    info!("Systray applet started");
+
+    // Run forever
+    future::pending().await
+}