slabtop: Add command

Cargo.toml

@@ -25,13 +25,7 @@ build = "build.rs"
 default = ["feat_common_core"]
 uudoc = []
 
-feat_common_core = [
-  "pwdx",
-  "free",
-  "w",
-  "watch",
-  "pmap",
-]
+feat_common_core = ["pwdx", "free", "w", "watch", "pmap", "slabtop"]
 
 [workspace.dependencies]
 uucore = "0.0.25"
@@ -51,6 +45,8 @@ bytesize = "1.3.0"
 chrono = { version = "0.4.37", default-features = false, features = [
   "clock",
 ] }
+ratatui = "0.26.1"
+crossterm = "0.27.0"
 
 [dependencies]
 clap = { workspace = true }
@@ -60,14 +56,16 @@ uucore = { workspace = true }
 phf = { workspace = true }
 textwrap = { workspace = true }
 sysinfo = { workspace = true }
-
+ratatui = { workspace = true }
+crossterm = { workspace = true }
 
 #
 pwdx = { optional = true, version = "0.0.1", package = "uu_pwdx", path = "src/uu/pwdx" }
 free = { optional = true, version = "0.0.1", package = "uu_free", path = "src/uu/free" }
 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" }
 pmap = { optional = true, version = "0.0.1", package = "uu_pmap", path = "src/uu/pmap" }
+slabtop = { optional = true, version = "0.0.1", package = "uu_slabtop", path = "src/uu/slabtop" }
 
 [dev-dependencies]
 pretty_assertions = "1"

src/uu/slabtop/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "uu_slabtop"
+version = "0.0.1"
+edition = "2021"
+authors = ["uutils developers"]
+license = "MIT"
+description = "slabtop ~ (uutils) Display kernel slab cache information in real time"
+
+homepage = "https://github.com/uutils/procps"
+repository = "https://github.com/uutils/procps/tree/main/src/uu/slabtop"
+keywords = ["acl", "uutils", "cross-platform", "cli", "utility"]
+categories = ["command-line-utilities"]
+
+
+[dependencies]
+uucore = { workspace = true }
+clap = { workspace = true }
+ratatui = { workspace = true }
+crossterm = { workspace = true }
+
+[lib]
+path = "src/slabtop.rs"
+
+[[bin]]
+name = "slabtop"
+path = "src/main.rs"

src/uu/slabtop/slabtop.md

@@ -0,0 +1,7 @@
+# slabtop
+
+```
+slabtop [options]
+```
+
+Display kernel slab cache information in real time

src/uu/slabtop/src/main.rs

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

src/uu/slabtop/src/parse.rs

@@ -0,0 +1,301 @@
+// 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.
+// spell-checker:ignore (words) symdir somefakedir
+
+use std::{
+    cmp::Ordering,
+    fs,
+    io::{Error, ErrorKind},
+};
+
+#[derive(Debug, Default)]
+pub struct SlabInfo {
+    #[allow(unused)] // for slabinfo checking
+    pub(crate) version: String,
+    pub(crate) meta: Vec<String>,
+    pub(crate) data: Vec<(String, Vec<u64>)>,
+}
+
+impl SlabInfo {
+    // parse slabinfo from /proc/slabinfo
+    // need root permission
+    pub fn new() -> Result<SlabInfo, Error> {
+        let content = fs::read_to_string("/proc/slabinfo")?;
+
+        Self::parse(content).ok_or(ErrorKind::Unsupported.into())
+    }
+
+    pub(crate) fn parse(content: String) -> Option<SlabInfo> {
+        let mut lines: Vec<&str> = content.lines().collect();
+
+        let version = parse_version(lines.remove(0))?;
+        let meta = parse_meta(lines.remove(0));
+        let data: Vec<(String, Vec<u64>)> = lines.into_iter().filter_map(parse_data).collect();
+
+        Some(SlabInfo {
+            version,
+            meta,
+            data,
+        })
+    }
+
+    pub fn fetch(&self, name: &str, meta: &str) -> Option<u64> {
+        // fetch meta's offset
+        let offset = self.offset(meta)?;
+
+        let (_, item) = self.data.iter().find(|(key, _)| key.eq(name))?;
+
+        item.get(offset).copied()
+    }
+
+    pub fn names(&self) -> Vec<&String> {
+        self.data.iter().map(|(k, _)| k).collect()
+    }
+
+    pub fn sort(mut self, by: char, ascending_order: bool) -> Self {
+        let mut sort = |by_meta: &str| {
+            if let Some(offset) = self.offset(by_meta) {
+                self.data.sort_by(|(_, data1), (_, data2)| {
+                    match (data1.get(offset), data2.get(offset)) {
+                        (Some(v1), Some(v2)) => {
+                            if ascending_order {
+                                v1.cmp(v2)
+                            } else {
+                                v2.cmp(v1)
+                            }
+                        }
+                        _ => Ordering::Equal,
+                    }
+                });
+            }
+        };
+
+        match by {
+            // <active_objs>
+            'a' => sort("active_objs"),
+            // <objperslab>
+            'b' => sort("objperslab"),
+            // <objsize> Maybe cache size I guess?
+            // TODO: Check is <objsize>
+            'c' => sort("objsize"),
+            // <num_slabs>
+            'l' => sort("num_slabs"),
+            // <active_slabs>
+            'v' => sort("active_slabs"),
+            // name, sort by lexicographical order
+            'n' => self.data.sort_by(|(name1, _), (name2, _)| {
+                if ascending_order {
+                    name1.cmp(name2)
+                } else {
+                    name2.cmp(name1)
+                }
+            }),
+            // <pagesperslab>
+            'p' => sort("pagesperslab"),
+            // <objsize>
+            's' => sort("objsize"),
+            // sort by cache utilization
+            'u' => {
+                let offset_active_objs = self.offset("active_objs");
+                let offset_num_objs = self.offset("num_objs");
+
+                if let (Some(offset_active_objs), Some(offset_num_objs)) =
+                    (offset_active_objs, offset_num_objs)
+                {
+                    self.data.sort_by(|(_, data1), (_, data2)| {
+                        let cu = |active_jobs: Option<&u64>, num_jobs: Option<&u64>| match (
+                            active_jobs,
+                            num_jobs,
+                        ) {
+                            (Some(active_jobs), Some(num_jobs)) => {
+                                Some((*active_jobs as f64) / (*num_jobs as f64))
+                            }
+                            _ => None,
+                        };
+                        let cu1 = cu(data1.get(offset_active_objs), data1.get(offset_num_objs));
+                        let cu2 = cu(data2.get(offset_active_objs), data2.get(offset_num_objs));
+
+                        if let (Some(cu1), Some(cu2)) = (cu1, cu2) {
+                            let result = if ascending_order {
+                                cu1.partial_cmp(&cu2)
+                            } else {
+                                cu2.partial_cmp(&cu1)
+                            };
+                            match result {
+                                Some(ord) => ord,
+                                None => Ordering::Equal,
+                            }
+                        } else {
+                            Ordering::Equal
+                        }
+                    })
+                }
+            }
+
+            // <num_objs>
+            // Default branch : `o`
+            _ => sort("num_objs"),
+        }
+
+        self
+    }
+
+    fn offset(&self, meta: &str) -> Option<usize> {
+        self.meta.iter().position(|it| it.eq(meta))
+    }
+
+    /////////////////////////////////// helpers ///////////////////////////////////
+
+    #[inline]
+    fn total(&self, meta: &str) -> u64 {
+        let Some(offset) = self.offset(meta) else {
+            return 0;
+        };
+
+        self.data
+            .iter()
+            .filter_map(|(_, data)| data.get(offset))
+            .sum::<u64>()
+    }
+
+    pub(crate) fn object_minimum(&self) -> u64 {
+        let Some(offset) = self.offset("objsize") else {
+            return 0;
+        };
+
+        match self
+            .data
+            .iter()
+            .filter_map(|(_, data)| data.get(offset))
+            .min()
+        {
+            Some(min) => *min,
+            None => 0,
+        }
+    }
+
+    pub(crate) fn object_maximum(&self) -> u64 {
+        let Some(offset) = self.offset("objsize") else {
+            return 0;
+        };
+
+        match self
+            .data
+            .iter()
+            .filter_map(|(_, data)| data.get(offset))
+            .max()
+        {
+            Some(max) => *max,
+            None => 0,
+        }
+    }
+
+    pub(crate) fn object_avg(&self) -> u64 {
+        let Some(offset) = self.offset("objsize") else {
+            return 0;
+        };
+
+        let iter = self.data.iter().filter_map(|(_, data)| data.get(offset));
+
+        let count = iter.clone().count();
+        let sum = iter.sum::<u64>();
+
+        if count == 0 {
+            0
+        } else {
+            (sum) / (count as u64)
+        }
+    }
+
+    pub(crate) fn total_active_objs(&self) -> u64 {
+        self.total("active_objs")
+    }
+
+    pub(crate) fn total_objs(&self) -> u64 {
+        self.total("num_objs")
+    }
+
+    pub(crate) fn total_active_slabs(&self) -> u64 {
+        self.total("active_slabs")
+    }
+
+    pub(crate) fn total_slabs(&self) -> u64 {
+        self.total("num_slabs")
+    }
+
+    pub(crate) fn total_active_size(&self) -> u64 {
+        self.names()
+            .iter()
+            .map(|name| {
+                self.fetch(name, "active_objs").unwrap_or_default()
+                    * self.fetch(name, "objsize").unwrap_or_default()
+            })
+            .sum::<u64>()
+    }
+
+    pub(crate) fn total_size(&self) -> u64 {
+        self.names()
+            .iter()
+            .map(|name| {
+                self.fetch(name, "num_objs").unwrap_or_default()
+                    * self.fetch(name, "objsize").unwrap_or_default()
+            })
+            .sum::<u64>()
+    }
+
+    pub(crate) fn total_active_cache(&self) -> u64 {
+        self.names()
+            .iter()
+            .map(|name| {
+                self.fetch(name, "objsize").unwrap_or_default()
+                    * self.fetch(name, "active_objs").unwrap_or_default()
+            })
+            .sum::<u64>()
+    }
+
+    pub(crate) fn total_cache(&self) -> u64 {
+        self.names()
+            .iter()
+            .map(|name| {
+                self.fetch(name, "objsize").unwrap_or_default()
+                    * self.fetch(name, "num_objs").unwrap_or_default()
+            })
+            .sum::<u64>()
+    }
+}
+
+pub(crate) fn parse_version(line: &str) -> Option<String> {
+    line.replace(':', " ")
+        .split_whitespace()
+        .last()
+        .map(String::from)
+}
+
+pub(crate) fn parse_meta(line: &str) -> Vec<String> {
+    line.replace(['#', ':'], " ")
+        .split_whitespace()
+        .filter(|it| it.starts_with('<') && it.ends_with('>'))
+        .map(|it| it.replace(['<', '>'], ""))
+        .collect()
+}
+
+pub(crate) fn parse_data(line: &str) -> Option<(String, Vec<u64>)> {
+    let split: Vec<String> = line
+        .replace(':', " ")
+        .split_whitespace()
+        .map(String::from)
+        .collect();
+
+    split.first().map(|name| {
+        (
+            name.to_string(),
+            split
+                .clone()
+                .into_iter()
+                .flat_map(|it| it.parse::<u64>())
+                .collect(),
+        )
+    })
+}