tload: Basic implementation of tload (#362)

* tload: add basic tui layout of modern look

* tload: set x-axis bound from 0 to the width of terminal

* tload: fix mismatched returning type

* tload: add `#[allow(clippy::cognitive_complexity)]`

* tload: add by-utils test

* tload: tweaks for max height of chart

* tload: bump version of `ratatui` from `0.28` to `0.29`

* tload: fix typo

* tload: set exit code to 130

* tload: fix typo

* tload: add license header for `tui.rs`

Cargo.toml

@@ -30,13 +30,14 @@ feat_common_core = [
     "pgrep",
     "pidof",
     "pidwait",
+    "pkill",
     "pmap",
     "ps",
     "pwdx",
     "slabtop",
     "snice",
-    "pkill",
     "sysctl",
+    "tload",
     "top",
     "w",
     "watch",
@@ -48,12 +49,14 @@ chrono = { version = "0.4.38", default-features = false, features = ["clock"] }
 clap = { version = "4.5.4", features = ["wrap_help", "cargo"] }
 clap_complete = "4.5.2"
 clap_mangen = "0.2.20"
+crossterm = "0.28.1"
 libc = "0.2.154"
 nix = { version = "0.29", default-features = false, features = ["process"] }
 phf = "0.11.2"
 phf_codegen = "0.11.2"
 prettytable-rs = "0.10.0"
 rand = { version = "0.9.0", features = ["small_rng"] }
+ratatui = "0.29.0"
 regex = "1.10.4"
 sysinfo = "0.33.0"
 tempfile = "3.10.1"
@@ -80,13 +83,14 @@ free = { optional = true, version = "0.0.1", package = "uu_free", path = "src/uu
 pgrep = { optional = true, version = "0.0.1", package = "uu_pgrep", path = "src/uu/pgrep" }
 pidof = { optional = true, version = "0.0.1", package = "uu_pidof", path = "src/uu/pidof" }
 pidwait = { optional = true, version = "0.0.1", package = "uu_pidwait", path = "src/uu/pidwait" }
+pkill = { optional = true, version = "0.0.1", package = "uu_pkill", path = "src/uu/pkill" }
 pmap = { optional = true, version = "0.0.1", package = "uu_pmap", path = "src/uu/pmap" }
 ps = { optional = true, version = "0.0.1", package = "uu_ps", path = "src/uu/ps" }
 pwdx = { optional = true, version = "0.0.1", package = "uu_pwdx", path = "src/uu/pwdx" }
 slabtop = { optional = true, version = "0.0.1", package = "uu_slabtop", path = "src/uu/slabtop" }
 snice = { optional = true, version = "0.0.1", package = "uu_snice", path = "src/uu/snice" }
-pkill = { optional = true, version = "0.0.1", package = "uu_pkill", path = "src/uu/pkill" }
 sysctl = { optional = true, version = "0.0.1", package = "uu_sysctl", path = "src/uu/sysctl" }
+tload = { optional = true, version = "0.0.1", package = "uu_tload", path = "src/uu/tload" }
 top = { optional = true, version = "0.0.1", package = "uu_top", path = "src/uu/top" }
 w = { optional = true, version = "0.0.1", package = "uu_w", path = "src/uu/w" }
 watch = { optional = true, version = "0.0.1", package = "uu_watch", path = "src/uu/watch" }

README.md

@@ -23,6 +23,7 @@ Ongoing:
 * `slabtop`: Displays detailed kernel slab cache information in real time.
 * `snice`: Changes the scheduling priority of a running process.
 * `sysctl`: Read or write kernel parameters at run-time.
+* `tload`: Prints a graphical representation of system load average to the terminal.
 * `top`: Displays real-time information about system processes.
 * `w`: Shows who is logged on and what they are doing.
 * `watch`: Executes a program periodically, showing output fullscreen.
@@ -30,7 +31,6 @@ Ongoing:
 TODO:
 * `hugetop`: Report hugepage usage of processes and the system as a whole.
 * `skill`: Sends a signal to processes based on criteria like user, terminal, etc.
-* `tload`: Prints a graphical representation of system load average to the terminal.
 * `vmstat`: Reports information about processes, memory, paging, block IO, traps, and CPU activity.
 
 Elsewhere:

src/uu/tload/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "uu_tload"
+version = "0.0.1"
+edition = "2021"
+authors = ["uutils developers"]
+license = "MIT"
+description = "tload ~ (uutils) graphic representation of system load average"
+
+homepage = "https://github.com/uutils/procps"
+repository = "https://github.com/uutils/procps/tree/main/src/uu/tload"
+keywords = ["acl", "uutils", "cross-platform", "cli", "utility"]
+categories = ["command-line-utilities"]
+
+[dependencies]
+clap = { workspace = true }
+crossterm = { workspace = true }
+ratatui = { workspace = true }
+uucore = { workspace = true }
+
+[lib]
+path = "src/tload.rs"
+
+[[bin]]
+name = "tload"
+path = "src/main.rs"

src/uu/tload/src/main.rs

@@ -0,0 +1 @@
+uucore::bin!(uu_tload);

src/uu/tload/src/tload.rs

@@ -0,0 +1,172 @@
+// This file is part of the uutils procps package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use std::collections::VecDeque;
+use std::sync::{Arc, RwLock};
+use std::thread::{self, sleep};
+use std::time::Duration;
+
+use clap::{arg, crate_version, value_parser, ArgAction, ArgMatches, Command};
+use crossterm::event::{self, KeyCode, KeyEvent, KeyModifiers};
+use tui::{LegacyTui, ModernTui};
+use uucore::{error::UResult, format_usage, help_about, help_usage};
+
+const ABOUT: &str = help_about!("tload.md");
+const USAGE: &str = help_usage!("tload.md");
+
+mod tui;
+
+#[derive(Debug, Default, Clone)]
+struct SystemLoadAvg {
+    pub(crate) last_1: f32,
+    pub(crate) last_5: f32,
+    pub(crate) last_10: f32,
+}
+
+impl SystemLoadAvg {
+    #[cfg(target_os = "linux")]
+    fn new() -> UResult<SystemLoadAvg> {
+        use std::fs;
+        use uucore::error::USimpleError;
+
+        let result = fs::read_to_string("/proc/loadavg")?;
+        let split = result.split(" ").collect::<Vec<_>>();
+
+        // Helper function to keep code clean
+        fn f(s: &str) -> UResult<f32> {
+            s.parse::<f32>()
+                .map_err(|e| USimpleError::new(1, e.to_string()))
+        }
+
+        Ok(SystemLoadAvg {
+            last_1: f(split[0])?,
+            last_5: f(split[1])?,
+            last_10: f(split[2])?,
+        })
+    }
+
+    #[cfg(not(target_os = "linux"))]
+    fn new() -> UResult<SystemLoadAvg> {
+        Ok(SystemLoadAvg::default())
+    }
+}
+
+#[allow(unused)]
+#[derive(Debug)]
+struct Settings {
+    delay: u64,
+    scale: usize, // Not used
+
+    is_modern: bool, // For modern display
+}
+
+impl Settings {
+    fn new(matches: &ArgMatches) -> Settings {
+        Settings {
+            delay: matches.get_one("delay").cloned().unwrap(),
+            scale: matches.get_one("scale").cloned().unwrap(),
+            is_modern: matches.get_flag("modern"),
+        }
+    }
+}
+
+#[uucore::main]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
+    let matches = uu_app().try_get_matches_from(args)?;
+    let settings = Settings::new(&matches);
+
+    let mut terminal = ratatui::init();
+
+    let data = {
+        // Why 10240?
+        //
+        // Emm, maybe there will be some terminal can display more than 10000 char?
+        let data = Arc::new(RwLock::new(VecDeque::with_capacity(10240)));
+        data.write()
+            .unwrap()
+            .push_back(SystemLoadAvg::new().unwrap());
+        data
+    };
+    let cloned_data = data.clone();
+    thread::spawn(move || loop {
+        sleep(Duration::from_secs(settings.delay));
+
+        let mut data = cloned_data.write().unwrap();
+        if data.iter().len() >= 10240 {
+            // Keep this VecDeque smaller than 10240
+            data.pop_front();
+        }
+        data.push_back(SystemLoadAvg::new().unwrap());
+    });
+
+    loop {
+        // Now only accept `Ctrl+C` for compatibility with the original implementation
+        //
+        // Use `event::poll` for non-blocking event reading
+        if let Ok(true) = event::poll(Duration::from_millis(10)) {
+            // If event available, break this loop
+            if let Ok(event::Event::Key(KeyEvent {
+                code: KeyCode::Char('c'),
+                modifiers: KeyModifiers::CONTROL,
+                ..
+            })) = event::read()
+            {
+                // compatibility with the original implementation
+                uucore::error::set_exit_code(130);
+                break;
+            }
+        }
+
+        terminal.draw(|frame| {
+            let data = &data.read().unwrap();
+            let data = data.iter().cloned().collect::<Vec<_>>();
+            frame.render_widget(
+                if settings.is_modern {
+                    ModernTui::new(&data)
+                } else {
+                    LegacyTui::new(&data)
+                },
+                frame.area(),
+            );
+        })?;
+
+        std::thread::sleep(Duration::from_millis(10));
+    }
+
+    ratatui::restore();
+    Ok(())
+}
+
+#[allow(clippy::cognitive_complexity)]
+pub fn uu_app() -> Command {
+    Command::new(uucore::util_name())
+        .version(crate_version!())
+        .about(ABOUT)
+        .override_usage(format_usage(USAGE))
+        .infer_long_args(true)
+        .args([
+            arg!(-d --delay     <secs>  "update delay in seconds")
+                .value_parser(value_parser!(u64))
+                .default_value("5")
+                .hide_default_value(true),
+            arg!(-m --modern            "modern look").action(ArgAction::SetTrue),
+            // TODO: Implement this arg
+            arg!(-s --scale <num>       "vertical scale")
+                .value_parser(value_parser!(usize))
+                .default_value("5")
+                .hide_default_value(true),
+        ])
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    // It's just a test to make sure if can parsing correctly.
+    #[test]
+    fn test_system_load_avg() {
+        let _ = SystemLoadAvg::new().expect("SystemLoadAvg::new");
+    }
+}

src/uu/tload/src/tui.rs

@@ -0,0 +1,119 @@
+// This file is part of the uutils procps package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use ratatui::{
+    buffer::Buffer,
+    layout::{Constraint, Direction, Layout, Rect},
+    style::{Style, Stylize},
+    symbols::Marker,
+    text::{Line, Text},
+    widgets::{Axis, Block, Borders, Chart, Dataset, GraphType, Paragraph, Widget},
+};
+
+use crate::SystemLoadAvg;
+
+pub(crate) struct ModernTui<'a>(&'a [SystemLoadAvg]);
+
+impl ModernTui<'_> {
+    fn render_header(&self, area: Rect, buf: &mut Buffer) {
+        let text = Text::from(vec![
+            Line::from(format!(
+                "Last 1 min load:   {:>5}",
+                self.0.last().unwrap().last_1
+            )),
+            Line::from(format!(
+                "Last 5 min load:   {:>5}",
+                self.0.last().unwrap().last_5
+            )),
+            Line::from(format!(
+                "Last 10 min load:  {:>5}",
+                self.0.last().unwrap().last_10
+            )),
+        ]);
+
+        Paragraph::new(text)
+            .style(Style::default().bold().italic())
+            .block(
+                Block::new()
+                    .borders(Borders::ALL)
+                    .title("System load history"),
+            )
+            .render(area, buf);
+    }
+
+    fn render_chart(&self, area: Rect, buf: &mut Buffer) {
+        let result = &self.0[self.0.len().saturating_sub(area.width.into())..]
+            .iter()
+            .enumerate()
+            .map(|(index, load)| (index as f64, load.last_1 as f64))
+            .collect::<Vec<_>>();
+
+        let data = Dataset::default()
+            .graph_type(GraphType::Line)
+            .marker(Marker::Braille)
+            .data(result);
+
+        let x_axis = {
+            let start = Line::from("0");
+            let middle = Line::from((area.width / 2).to_string());
+            let end = Line::from(area.width.to_string());
+            Axis::default()
+                .title("Time(per delay)")
+                .bounds([0.0, area.width.into()])
+                .labels(vec![start, middle, end])
+        };
+
+        // Why this tweak?
+        //
+        // Sometime the chart cannot display all the line because of max height are equals the max
+        // load of system in the history, so I add 0.2*{max_load} to the height of chart make it
+        // display beautiful
+        let y_axis_upper_bound = result.iter().map(|it| it.1).reduce(f64::max).unwrap_or(0.0);
+        let y_axis_upper_bound = y_axis_upper_bound + y_axis_upper_bound * 0.2;
+        let label = {
+            let min = "0.0".to_owned();
+            let mid = format!("{:.1}", y_axis_upper_bound / 2.0);
+            let max = format!("{:.1}", y_axis_upper_bound);
+            vec![min, mid, max]
+        };
+        let y_axis = Axis::default()
+            .bounds([0.0, y_axis_upper_bound])
+            .labels(label)
+            .title("System Load");
+
+        Chart::new(vec![data])
+            .x_axis(x_axis)
+            .y_axis(y_axis)
+            .render(area, buf);
+    }
+}
+
+impl ModernTui<'_> {
+    pub(crate) fn new(input: &[SystemLoadAvg]) -> ModernTui<'_> {
+        ModernTui(input)
+    }
+}
+
+impl Widget for ModernTui<'_> {
+    fn render(self, area: ratatui::prelude::Rect, buf: &mut ratatui::prelude::Buffer)
+    where
+        Self: Sized,
+    {
+        let layout = Layout::new(
+            Direction::Vertical,
+            [Constraint::Length(5), Constraint::Min(0)],
+        )
+        .split(area);
+
+        let header = layout[0];
+        let chart = layout[1];
+
+        self.render_header(header, buf);
+        self.render_chart(chart, buf);
+    }
+}
+
+// TODO: Implemented LegacyTui
+pub(crate) type LegacyTui<'a> = ModernTui<'a>;

src/uu/tload/tload.md

@@ -0,0 +1,7 @@
+# tload
+
+```
+tload [options] [tty]
+```
+
+tload prints a graph of the current system load average to the specified tty (or the tty of the tload process if none is specified).

tests/by-util/test_tload.rs

@@ -0,0 +1,11 @@
+// This file is part of the uutils procps package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use crate::common::util::TestScenario;
+
+#[test]
+fn test_invalid_arg() {
+    new_ucmd!().arg("--definitely-invalid").fails().code_is(1);
+}

tests/tests.rs

@@ -60,3 +60,7 @@ mod test_pkill;
 #[cfg(feature = "sysctl")]
 #[path = "by-util/test_sysctl.rs"]
 mod test_sysctl;
+
+#[cfg(feature = "tload")]
+#[path = "by-util/test_tload.rs"]
+mod test_tload;