top: implement SUMMARY display

todo:
io wait(only Linux now)
cpu load average for Windows
cpu load for Macos
active user count
determine memory unit from `--scale-summary-mem`

Cargo.toml

@@ -63,6 +63,7 @@ uucore = "0.0.29"
 walkdir = "2.5.0"
 windows = { version = "0.59.0" }
 xattr = "1.3.1"
+systemstat = "0.2.4"
 
 [dependencies]
 clap = { workspace = true }

src/uu/top/Cargo.toml

@@ -19,6 +19,8 @@ nix = { workspace = true }
 prettytable-rs = { workspace = true }
 sysinfo = { workspace = true }
 chrono = { workspace = true }
+systemstat = { workspace = true }
+bytesize = { workspace = true }
 
 [lib]
 path = "src/top.rs"

src/uu/top/src/header.rs

@@ -0,0 +1,232 @@
+use crate::picker::{sysinfo, systemstat};
+use bytesize::ByteSize;
+use systemstat::Platform;
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
+use {
+    std::sync::{Mutex, OnceLock},
+    systemstat::{CPULoad, DelayedMeasurement},
+};
+
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
+static LOAD_AVERAGE: OnceLock<Mutex<DelayedMeasurement<CPULoad>>> = OnceLock::new();
+
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
+pub(crate) fn cpu_load() -> CPULoad {
+    match LOAD_AVERAGE.get() {
+        None => {
+            LOAD_AVERAGE.get_or_init(|| {
+                Mutex::new(systemstat().read().unwrap().cpu_load_aggregate().unwrap())
+            });
+            systemstat()
+                .read()
+                .unwrap()
+                .cpu_load_aggregate()
+                .unwrap()
+                .done()
+                .unwrap()
+        }
+        Some(v) => {
+            let mut v = v.lock().unwrap();
+            let load = v.done().unwrap();
+            *v = systemstat().read().unwrap().cpu_load_aggregate().unwrap();
+            load
+        }
+    }
+}
+
+pub(crate) fn header() -> String {
+    format!(
+        "top - {time} {uptime}, {user}, {load_average}\n\
+        {task}\n\
+        {cpu}\n\
+        {memory}\n\
+        {swap}",
+        time = chrono::Local::now().format("%H:%M:%S"),
+        uptime = uptime(),
+        user = user(),
+        load_average = load_average(),
+        task = task(),
+        cpu = cpu(),
+        memory = memory(),
+        swap = swap(),
+    )
+}
+
+fn todo() -> String {
+    "TODO".into()
+}
+
+fn format_memory(memory_b: u64, unit: u64) -> f64 {
+    ByteSize::b(memory_b).0 as f64 / unit as f64
+}
+
+fn uptime() -> String {
+    let binding = systemstat().read().unwrap();
+
+    let up_seconds = binding.uptime().unwrap().as_secs();
+    let up_minutes = (up_seconds % (60 * 60)) / 60;
+    let up_hours = (up_seconds % (24 * 60 * 60)) / (60 * 60);
+    let up_days = up_seconds / (24 * 60 * 60);
+
+    let mut res = String::from("up ");
+
+    if up_days > 0 {
+        res.push_str(&format!(
+            "{} day{}, ",
+            up_days,
+            if up_days > 1 { "s" } else { "" }
+        ));
+    }
+    if up_hours > 0 {
+        res.push_str(&format!("{}:{:0>2}", up_hours, up_minutes));
+    } else {
+        res.push_str(&format!("{} min", up_minutes));
+    }
+
+    res
+}
+
+//TODO: Implement active user count
+fn user() -> String {
+    todo()
+}
+
+#[cfg(not(target_os = "windows"))]
+fn load_average() -> String {
+    let binding = systemstat().read().unwrap();
+
+    let load_average = binding.load_average().unwrap();
+    format!(
+        "load average: {:.2}, {:.2}, {:.2}",
+        load_average.one, load_average.five, load_average.fifteen
+    )
+}
+
+#[cfg(target_os = "windows")]
+fn load_average() -> String{
+    todo()
+}
+
+fn task() -> String {
+    let binding = sysinfo().read().unwrap();
+
+    let process = binding.processes();
+    let mut running_process = 0;
+    let mut sleeping_process = 0;
+    let mut stopped_process = 0;
+    let mut zombie_process = 0;
+
+    for (_, process) in process.iter() {
+        match process.status() {
+            sysinfo::ProcessStatus::Run => running_process += 1,
+            sysinfo::ProcessStatus::Sleep => sleeping_process += 1,
+            sysinfo::ProcessStatus::Stop => stopped_process += 1,
+            sysinfo::ProcessStatus::Zombie => zombie_process += 1,
+            _ => {}
+        };
+    }
+
+    format!(
+        "Tasks: {} total, {} running, {} sleeping, {} stopped, {} zombie",
+        process.len(),
+        running_process,
+        sleeping_process,
+        stopped_process,
+        zombie_process,
+    )
+}
+
+#[cfg(target_os = "linux")]
+fn cpu() -> String {
+    let file = std::fs::File::open(std::path::Path::new("/proc/stat")).unwrap();
+    let content = std::io::read_to_string(file).unwrap();
+    let load = content
+        .lines()
+        .next()
+        .unwrap()
+        .strip_prefix("cpu")
+        .unwrap()
+        .split(' ')
+        .filter(|s| !s.is_empty())
+        .collect::<Vec<_>>();
+    let user = load[0].parse::<f64>().unwrap();
+    let nice = load[1].parse::<f64>().unwrap();
+    let system = load[2].parse::<f64>().unwrap();
+    let idle = load[3].parse::<f64>().unwrap_or_default(); // since 2.5.41
+    let io_wait = load[4].parse::<f64>().unwrap_or_default(); // since 2.5.41
+    let hardware_interrupt = load[5].parse::<f64>().unwrap_or_default(); // since 2.6.0
+    let software_interrupt = load[6].parse::<f64>().unwrap_or_default(); // since 2.6.0
+    let steal_time = load[7].parse::<f64>().unwrap_or_default(); // since 2.6.11
+                                                                 // GNU do not show guest and guest_nice
+    let guest = load[8].parse::<f64>().unwrap_or_default(); // since 2.6.24
+    let guest_nice = load[9].parse::<f64>().unwrap_or_default(); // since 2.6.33
+    let total = user
+        + nice
+        + system
+        + idle
+        + io_wait
+        + hardware_interrupt
+        + software_interrupt
+        + steal_time
+        + guest
+        + guest_nice;
+
+    format!(
+        "%Cpu(s):  {:.1} us, {:.1} sy, {:.1} ni, {:.1} id, {:.1} wa, {:.1} hi, {:.1} si, {:.1} st",
+        user / total * 100.0,
+        system / total * 100.0,
+        nice / total * 100.0,
+        idle / total * 100.0,
+        io_wait / total * 100.0,
+        hardware_interrupt / total * 100.0,
+        software_interrupt / total * 100.0,
+        steal_time / total * 100.0,
+    )
+}
+
+//TODO: Implement io wait, hardware interrupt, software interrupt and steal time
+#[cfg(not(any(target_os = "macos", target_os = "linux")))]
+fn cpu() -> String {
+    let cpu = cpu_load();
+    format!(
+        "%Cpu(s):  {:.1} us,  {:.1} sy,  {:.1} ni, {:.1} id",
+        cpu.user * 100.0,
+        cpu.system * 100.0,
+        cpu.nice * 100.0,
+        cpu.idle * 100.0
+    )
+}
+
+//TODO: Implement for macos
+#[cfg(target_os = "macos")]
+fn cpu() -> String {
+    todo()
+}
+
+fn memory() -> String {
+    let binding = sysinfo().read().unwrap();
+    //TODO: unit from argument
+    let unit = bytesize::MIB;
+
+    format!(
+        "MiB Mem : {:8.1} total, {:8.1} free, {:8.1} used, {:8.1} buff/cache",
+        format_memory(binding.total_memory(), unit),
+        format_memory(binding.free_memory(), unit),
+        format_memory(binding.used_memory(), unit),
+        format_memory(binding.total_memory() - binding.free_memory(), unit),
+    )
+}
+
+fn swap() -> String {
+    let binding = sysinfo().read().unwrap();
+    //TODO: unit from argument
+    let unit = bytesize::MIB;
+
+    format!(
+        "MiB Swap: {:8.1} total, {:8.1} free, {:8.1} used, {:8.1} avail Mem",
+        format_memory(binding.total_swap(), unit),
+        format_memory(binding.free_swap(), unit),
+        format_memory(binding.used_swap(), unit),
+        format_memory(binding.total_memory() - binding.free_memory(), unit),
+    )
+}

src/uu/top/src/picker.rs

@@ -12,13 +12,19 @@ use std::{
     sync::{OnceLock, RwLock},
 };
 use sysinfo::{Pid, System, Users};
+use systemstat::Platform;
 
 static SYSINFO: OnceLock<RwLock<System>> = OnceLock::new();
+static SYSTEMSTAT: OnceLock<RwLock<systemstat::System>> = OnceLock::new();
 
 pub fn sysinfo() -> &'static RwLock<System> {
     SYSINFO.get_or_init(|| RwLock::new(System::new_all()))
 }
 
+pub fn systemstat() -> &'static RwLock<systemstat::System> {
+    SYSTEMSTAT.get_or_init(|| RwLock::new(systemstat::System::new()))
+}
+
 pub(crate) fn pickers(fields: &[String]) -> Vec<Box<dyn Fn(u32) -> String>> {
     fields
         .iter()

src/uu/top/src/top.rs

@@ -4,6 +4,7 @@
 // file that was distributed with this source code.
 
 use clap::{arg, crate_version, value_parser, ArgAction, ArgGroup, ArgMatches, Command};
+use header::header;
 use picker::pickers;
 use picker::sysinfo;
 use prettytable::{format::consts::FORMAT_CLEAN, Row, Table};
@@ -18,6 +19,7 @@ const ABOUT: &str = help_about!("top.md");
 const USAGE: &str = help_usage!("top.md");
 
 mod field;
+mod header;
 mod picker;
 
 #[allow(unused)]
@@ -53,6 +55,9 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     // Must refresh twice.
     // https://docs.rs/sysinfo/0.31.2/sysinfo/struct.System.html#method.refresh_cpu_usage
     picker::sysinfo().write().unwrap().refresh_all();
+    // Similar to the above.
+    #[cfg(not(any(target_os = "macos", target_os = "linux")))]
+    crate::header::cpu_load();
     sleep(Duration::from_millis(200));
     picker::sysinfo().write().unwrap().refresh_all();
 
@@ -157,11 +162,6 @@ where
     }
 }
 
-// TODO: Implement information collecting.
-fn header() -> String {
-    "TODO".into()
-}
-
 // TODO: Implement fields selecting
 fn selected_fields() -> Vec<String> {
     vec![