feat: process list

this is unnacceptably unperformant;
I think I've reached the point at which sysinfo doesn't do what I want,
which is keep track of a table of processes efficiently enough.

Cargo.lock

@@ -292,6 +292,9 @@ name = "bitflags"
 version = "2.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b588b76d00fde79687d7646a9b5bdf3cc0f655e0bbd080335a95d7e96f3587da"
+dependencies = [
+ "serde_core",
+]
 
 [[package]]
 name = "block"
@@ -1380,6 +1383,8 @@ name = "itop"
 version = "0.1.0"
 dependencies = [
  "iced",
+ "ron",
+ "serde",
  "smol",
  "sysinfo",
 ]
@@ -2482,6 +2487,20 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "19b30a45b0cd0bcca8037f3d0dc3421eaf95327a17cad11964fb8179b4fc4832"
 
+[[package]]
+name = "ron"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "81116b9531d61eabc41aeb228e4b6b2435bcca3233b98cf3b3077d4e6e9debb3"
+dependencies = [
+ "bitflags 2.13.1",
+ "once_cell",
+ "serde",
+ "serde_derive",
+ "typeid",
+ "unicode-ident",
+]
+
 [[package]]
 name = "roxmltree"
 version = "0.20.0"
@@ -3091,6 +3110,12 @@ dependencies = [
  "core_maths",
 ]
 
+[[package]]
+name = "typeid"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bc7d623258602320d5c55d1bc22793b57daff0ec7efc270ea7d55ce1d5f5471c"
+
 [[package]]
 name = "uds_windows"
 version = "1.2.1"

Cargo.toml

@@ -5,10 +5,23 @@ license = "AGPL-3.0-or-later"
 version = "0.1.0"
 edition = "2024"
 
+[features]
+default = [ "app" ]
+app = [ "dep:iced", "dep:smol" ]
+
 [dependencies]
-smol = "2.0.2"
+ron = "0.12.2"
 sysinfo = "0.39.6"
 
 [dependencies.iced]
 version = "0.14.0"
 features = [ "canvas", "smol" ]
+optional = true
+
+[dependencies.smol]
+version = "2.0.2"
+optional = true
+
+[dependencies.serde]
+version = "1.0.229"
+features = [ "derive" ]

flake.nix

@@ -58,7 +58,6 @@
             desktopItem = pkgs.makeDesktopItem {
               inherit name;
               desktopName = name;
-              icon = name;
               exec = name;
             };
           in
@@ -89,6 +88,13 @@
       {
         packages.default = crate;
 
+        packages."${name}-server-only" = craneLib.buildPackage {
+          name = "${name}-server-only";
+          src = ./.;
+          doCheck = false;
+          cargoExtraArgs = "--locked --no-default-features";
+        };
+
         checks = {
           crate-clippy = craneLib.cargoClippy (
             commonArgs

src/app/graph.rs

@@ -6,18 +6,42 @@ use crate::app;
 
 const CYAN: Color = Color::from_rgb8(0, 255, 255);
 
-#[derive(Default)]
 pub struct Graph {
-    pub cache: canvas::Cache,
     timeline: VecDeque<f32>,
+
+    pub show_borders: bool,
+    pub cache: canvas::Cache,
+}
+impl Default for Graph {
+    fn default() -> Self {
+        Self {
+            show_borders: true,
+
+            timeline: Default::default(),
+            cache: Default::default(),
+        }
+    }
 }
 
 impl Graph {
+    pub fn new(value: f32) -> Self {
+        Self {
+            timeline: {
+                let mut vec = VecDeque::new();
+                vec.push_front(value);
+                vec
+            },
+            ..Default::default()
+        }
+    }
+
     pub fn update(&mut self, value: f32) {
         self.timeline.push_back(value);
-        if self.timeline.len() > 1000 {
+        if self.timeline.len() > 500 {
             self.timeline.pop_front();
         }
+
+        self.cache.clear();
     }
 }
 
@@ -32,11 +56,19 @@ impl canvas::Program<app::Message, Theme, Renderer> for Graph {
         _cursor: mouse::Cursor,
     ) -> Vec<canvas::Geometry<Renderer>> {
         let geometry = self.cache.draw(renderer, bounds.size(), |frame| {
+            if self.show_borders {
+                frame.stroke_rectangle(
+                    Point::new(0., 0.),
+                    bounds.size(),
+                    canvas::Stroke::default().with_color(Color::from_rgb8(255, 0, 0)),
+                );
+            }
             frame.stroke(
                 &canvas::Path::new(|builder| {
                     for (index, value) in self.timeline.iter().enumerate() {
                         let x = index as f32 / self.timeline.len() as f32 * bounds.width;
-                        let y = bounds.height - value / 100. * bounds.height;
+                        let y = (bounds.height - value / 100. * bounds.height)
+                            .clamp(1., bounds.height - 1.);
                         builder.line_to(Point::new(x, y))
                     }
                 }),

src/app/info_stream.rs

@@ -0,0 +1,64 @@
+use std::env;
+
+use iced::{
+    Task,
+    futures::{self, SinkExt},
+    stream,
+};
+use ron::de;
+use smol::{Timer, unblock};
+
+use crate::{
+    app,
+    sysinfo_snapshot::{self, SysinfoSnapshot},
+};
+
+pub fn create() -> Task<app::Message> {
+    if env::args()
+        .nth(1)
+        .is_some_and(|command| command == "client")
+    {
+        Task::run(
+            stream::channel(
+                1,
+                async |mut sender: futures::channel::mpsc::Sender<SysinfoSnapshot>| {
+                    let mut buf = String::new();
+                    loop {
+                        buf = unblock(move || {
+                            std::io::stdin().read_line(&mut buf).unwrap();
+                            buf
+                        })
+                        .await;
+
+                        match de::from_str(&buf) {
+                            Ok(info) => sender.send(info).await.unwrap(),
+                            Err(e) => eprintln!("{e}"),
+                        }
+                        buf.clear();
+                    }
+                },
+            ),
+            app::Message::Info,
+        )
+    } else {
+        Task::run(
+            stream::channel(
+                1,
+                async |mut sender: futures::channel::mpsc::Sender<SysinfoSnapshot>| {
+                    let mut sys = sysinfo::System::new();
+                    let refreshes = sysinfo_snapshot::refreshes();
+
+                    sys.refresh_specifics(refreshes);
+                    Timer::after(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL).await;
+
+                    loop {
+                        sys.refresh_specifics(refreshes);
+                        sender.send(SysinfoSnapshot::from(&sys)).await.unwrap();
+                        Timer::after(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL).await;
+                    }
+                },
+            ),
+            app::Message::Info,
+        )
+    }
+}

src/app/mod.rs

@@ -1,66 +1,198 @@
-use iced::{
-    Color, Element, Length, Renderer, Task, Theme, application, futures::SinkExt, stream, theme,
-    widget,
-};
-use smol::Timer;
+use std::time::Duration;
 
-use crate::app::graph::Graph;
+use iced::{
+    Color, Error, Event, Length, Renderer, Subscription, Task, Theme, application, event,
+    keyboard::{self, Key},
+    theme, widget,
+};
+
+use crate::{
+    app::{graph::Graph, utils::maybe_widget},
+    sysinfo_snapshot::{ProcessSnapshot, SysinfoSnapshot},
+    utils::Toggle,
+};
 
 mod graph;
+mod info_stream;
+mod utils;
+
+type Element<'a> = iced::Element<'a, Message, Theme, Renderer>;
 
 enum Message {
-    Cpu(f32),
+    ToggleMain,
+    ToggleCpu,
+    ToggleMemory,
+    ToggleProcesses,
+
+    Info(SysinfoSnapshot),
 }
 
+#[derive(Default)]
 struct State {
-    cpu_graph: Graph,
+    uptime: Duration,
+
+    is_main_section_shown: bool,
+    total_cpu_graph: Graph,
+
+    is_cpu_section_shown: bool,
+    cpu_graphs: Vec<Graph>,
+
+    is_memory_section_shown: bool,
+    memory_graph: Graph,
+    swap_graph: Graph,
+
+    is_processes_section_shown: bool,
+    processes: Vec<ProcessSnapshot>,
 }
 
 impl State {
     fn new() -> (Self, Task<Message>) {
-        (
-            Self {
-                cpu_graph: Default::default(),
-            },
-            Task::run(
-                stream::channel(1, async |mut sender| {
-                    let mut sys = sysinfo::System::new();
-                    let refreshes = sysinfo::RefreshKind::nothing()
-                        .with_cpu(sysinfo::CpuRefreshKind::nothing().with_cpu_usage());
+        let mut state = Self {
+            is_main_section_shown: true,
+            ..Default::default()
+        };
+        state.total_cpu_graph.show_borders = false;
 
-                    sys.refresh_specifics(refreshes);
-                    Timer::after(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL).await;
-
-                    loop {
-                        sys.refresh_specifics(refreshes);
-                        Timer::after(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL).await;
-                        sender.send(sys.global_cpu_usage()).await.unwrap();
-                    }
-                }),
-                Message::Cpu,
-            ),
-        )
+        (state, info_stream::create())
     }
     fn update(&mut self, message: Message) -> Task<Message> {
         match message {
-            Message::Cpu(value) => {
-                self.cpu_graph.update(value);
-                self.cpu_graph.cache.clear();
+            Message::ToggleMain => {
+                self.is_main_section_shown.toggle();
+                self.check_borders();
+            }
+            Message::ToggleCpu => {
+                self.is_cpu_section_shown.toggle();
+                self.check_borders();
+            }
+            Message::ToggleMemory => {
+                self.is_memory_section_shown.toggle();
+                self.check_borders();
+            }
+            Message::ToggleProcesses => {
+                self.is_processes_section_shown.toggle();
+                self.check_borders();
+            }
+
+            Message::Info(snapshot) => {
+                self.uptime = snapshot.uptime();
+
+                self.total_cpu_graph.update(snapshot.cpu_total);
+
+                self.memory_graph
+                    .update(snapshot.memory as f32 / snapshot.memory_total as f32 * 100.);
+
+                self.swap_graph
+                    .update(snapshot.swap as f32 / snapshot.swap_total as f32 * 100.);
+
+                if self.cpu_graphs.len() != snapshot.cpus.len() {
+                    self.cpu_graphs = snapshot
+                        .cpus
+                        .into_iter()
+                        .map(|value| Graph::new(value))
+                        .collect();
+                } else {
+                    self.cpu_graphs
+                        .iter_mut()
+                        .zip(snapshot.cpus.into_iter())
+                        .for_each(|(graph, value)| graph.update(value));
+                }
+
+                self.processes = snapshot.processes;
+                self.processes
+                    .sort_by(|a, b| b.cpu_usage.total_cmp(&a.cpu_usage));
             }
         }
 
         Task::none()
     }
-    fn view(&self) -> Element<'_, Message, Theme, Renderer> {
-        widget::Canvas::new(&self.cpu_graph)
-            .width(Length::Fill)
-            .height(Length::Fill)
-            .into()
+    fn view(&self) -> Element<'_> {
+        widget::column([
+            widget::row([
+                maybe_widget(self.is_main_section_shown, || {
+                    widget::canvas(&self.total_cpu_graph)
+                        .width(Length::Fill)
+                        .height(Length::Fill)
+                        .into()
+                }),
+                maybe_widget(self.is_cpu_section_shown, || {
+                    widget::grid(
+                        self.cpu_graphs
+                            .iter()
+                            .map(|graph| widget::Canvas::new(graph).into()),
+                    )
+                    .columns(2)
+                    .height(Length::Fill)
+                    .into()
+                }),
+            ])
+            .into(),
+            widget::row([
+                maybe_widget(self.is_memory_section_shown, || {
+                    widget::row([
+                        widget::canvas(&self.memory_graph)
+                            .width(Length::Fill)
+                            .height(Length::Fill)
+                            .into(),
+                        widget::canvas(&self.swap_graph)
+                            .width(Length::Fill)
+                            .height(Length::Fill)
+                            .into(),
+                    ])
+                    .into()
+                }),
+                maybe_widget(self.is_processes_section_shown, || {
+                    widget::scrollable(
+                        widget::grid(self.processes.iter().flat_map(|process| {
+                            [
+                                widget::text(&process.name).into(),
+                                widget::text(process.cpu_usage).into(),
+                                widget::text(format!("{:?}", process.cpu_time())).into(),
+                                widget::text(process.pid).into(),
+                            ]
+                        }))
+                        .height(Length::Shrink)
+                        .columns(4),
+                    )
+                    .width(Length::Fill)
+                    .height(Length::Fill)
+                    .into()
+                }),
+            ])
+            .into(),
+        ])
+        .into()
+    }
+
+    fn subscription(&self) -> Subscription<Message> {
+        event::listen().filter_map(|event| match event {
+            Event::Keyboard(keyboard::Event::KeyPressed { modified_key, .. }) => {
+                match modified_key.as_ref() {
+                    Key::Character("M" | "1") => Some(Message::ToggleMain),
+                    Key::Character("c" | "2") => Some(Message::ToggleCpu),
+                    Key::Character("m" | "3") => Some(Message::ToggleMemory),
+                    Key::Character("p" | "4") => Some(Message::ToggleProcesses),
+                    _ => None,
+                }
+            }
+            _ => None,
+        })
+    }
+
+    fn title(&self) -> String {
+        format!("itop {:?}", self.uptime)
+    }
+
+    fn check_borders(&mut self) {
+        self.total_cpu_graph.show_borders =
+            self.is_cpu_section_shown || self.is_memory_section_shown;
     }
 }
 
-pub fn run() -> Result<(), impl std::error::Error> {
+pub fn run() -> Result<(), Error> {
     application(State::new, State::update, State::view)
+        .subscription(State::subscription)
+        .title(State::title)
         .theme(theme::Theme::custom(
             "high-contrast-dark",
             theme::Palette {

src/app/utils.rs

@@ -0,0 +1,14 @@
+use iced::widget;
+
+use crate::app;
+
+pub fn maybe_widget<'a>(
+    condition: bool,
+    widget: impl FnOnce() -> app::Element<'a>,
+) -> app::Element<'a> {
+    if condition {
+        widget()
+    } else {
+        widget::space().into()
+    }
+}

src/main.rs

@@ -1,5 +1,19 @@
-mod app;
+use std::env;
 
-fn main() -> Result<(), impl std::error::Error> {
-    app::run()
+#[cfg(feature = "app")]
+mod app;
+mod server;
+mod sysinfo_snapshot;
+mod utils;
+
+fn main() {
+    match env::args().nth(1).as_deref() {
+        #[cfg(feature = "app")]
+        None | Some("client") => app::run().unwrap(),
+
+        #[cfg_attr(feature = "app", allow(unreachable_patterns))]
+        None | Some("server") => server::run().unwrap(),
+
+        Some(s) => panic!("invalid argument: {s}"),
+    }
 }

src/server/mod.rs

@@ -0,0 +1,21 @@
+use std::{io::Write, thread};
+
+use ron::{Error, ser};
+
+use crate::sysinfo_snapshot::{self, SysinfoSnapshot};
+
+pub fn run() -> Result<(), Error> {
+    let mut sys = sysinfo::System::new();
+    let refreshes = sysinfo_snapshot::refreshes();
+
+    sys.refresh_specifics(refreshes);
+    thread::sleep(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL);
+
+    let mut stdout = std::io::stdout();
+
+    loop {
+        sys.refresh_specifics(refreshes);
+        stdout.write_all((ser::to_string(&SysinfoSnapshot::from(&sys))? + "\n").as_bytes())?;
+        thread::sleep(sysinfo::MINIMUM_CPU_UPDATE_INTERVAL);
+    }
+}

src/sysinfo_snapshot.rs

@@ -0,0 +1,87 @@
+use std::time::Duration;
+
+pub fn refreshes() -> sysinfo::RefreshKind {
+    sysinfo::RefreshKind::nothing()
+        .with_memory(sysinfo::MemoryRefreshKind::everything())
+        .with_cpu(sysinfo::CpuRefreshKind::nothing().with_cpu_usage())
+        .with_processes(
+            sysinfo::ProcessRefreshKind::nothing()
+                .with_cpu()
+                .with_cmd(sysinfo::UpdateKind::OnlyIfNotSet)
+                .with_exe(sysinfo::UpdateKind::OnlyIfNotSet),
+        )
+}
+
+#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
+pub struct SysinfoSnapshot {
+    /// in seconds
+    uptime: u64,
+
+    pub cpu_total: f32,
+    pub cpus: Vec<f32>,
+
+    pub memory: u64,
+    pub memory_total: u64,
+    pub swap: u64,
+    pub swap_total: u64,
+
+    pub processes: Vec<ProcessSnapshot>,
+}
+impl SysinfoSnapshot {
+    #[cfg_attr(not(feature = "app"), allow(dead_code))]
+    pub fn uptime(&self) -> Duration {
+        Duration::from_secs(self.uptime)
+    }
+}
+
+impl From<&sysinfo::System> for SysinfoSnapshot {
+    fn from(value: &sysinfo::System) -> Self {
+        Self {
+            uptime: sysinfo::System::uptime(),
+
+            cpu_total: value.global_cpu_usage(),
+            cpus: value.cpus().iter().map(|cpu| cpu.cpu_usage()).collect(),
+
+            memory: value.used_memory(),
+            memory_total: value.total_memory(),
+            swap: value.used_swap(),
+            swap_total: value.total_swap(),
+
+            processes: value
+                .processes()
+                .iter()
+                .map(|(_pid, process)| ProcessSnapshot::from(process))
+                .collect(),
+        }
+    }
+}
+
+#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
+pub struct ProcessSnapshot {
+    pub pid: usize,
+
+    /// in CPU-milliseconds
+    accumulated_cpu_time: u64,
+
+    /// note: it's by core, and can be up to eg 1600 on a 16-core device
+    pub cpu_usage: f32,
+
+    pub name: String,
+}
+impl ProcessSnapshot {
+    pub fn cpu_time(&self) -> Duration {
+        Duration::from_millis(self.accumulated_cpu_time)
+    }
+}
+
+impl From<&sysinfo::Process> for ProcessSnapshot {
+    fn from(value: &sysinfo::Process) -> Self {
+        Self {
+            pid: value.pid().into(),
+            accumulated_cpu_time: value.accumulated_cpu_time(),
+            cpu_usage: value.cpu_usage(),
+
+            name: value.name().to_string_lossy().into_owned(),
+        }
+    }
+}

src/utils.rs

@@ -0,0 +1,10 @@
+#[cfg_attr(not(feature = "app"), allow(dead_code))]
+pub trait Toggle {
+    fn toggle(&mut self);
+}
+
+impl Toggle for bool {
+    fn toggle(&mut self) {
+        *self = !*self
+    }
+}