WIP: choom

Cargo.lock

@@ -969,6 +969,7 @@ dependencies = [
  "tempfile",
  "textwrap",
  "uu_blockdev",
+ "uu_choom",
  "uu_ctrlaltdel",
  "uu_dmesg",
  "uu_fsfreeze",
@@ -994,6 +995,15 @@ dependencies = [
  "uucore",
 ]
 
+[[package]]
+name = "uu_choom"
+version = "0.0.1"
+dependencies = [
+ "clap",
+ "linux-raw-sys 0.9.2",
+ "uucore",
+]
+
 [[package]]
 name = "uu_ctrlaltdel"
 version = "0.0.1"

Cargo.toml

@@ -27,6 +27,7 @@ uudoc = []
 
 feat_common_core = [
   "blockdev",
+  "choom",
   "ctrlaltdel",
   "dmesg",
   "fsfreeze",
@@ -72,6 +73,7 @@ uucore = { workspace = true }
 
 #
 blockdev = { optional = true, version = "0.0.1", package = "uu_blockdev", path = "src/uu/blockdev" }
+choom = { optional = true, version = "0.0.1", package = "uu_choom", path = "src/uu/choom" }
 ctrlaltdel = { optional = true, version = "0.0.1", package = "uu_ctrlaltdel", path = "src/uu/ctrlaltdel" }
 dmesg = { optional = true, version = "0.0.1", package = "uu_dmesg", path = "src/uu/dmesg" }
 fsfreeze = { optional = true, version = "0.0.1", package = "uu_fsfreeze", path = "src/uu/fsfreeze" }

src/uu/choom/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "uu_choom"
+version = "0.0.1"
+edition = "2021"
+
+[lib]
+path = "src/choom.rs"
+
+[[bin]]
+name = "choom"
+path = "src/main.rs"
+
+[dependencies]
+clap = { workspace = true }
+linux-raw-sys = { workspace = true }
+uucore = { workspace = true }

src/uu/choom/choom.md

@@ -0,0 +1,9 @@
+# choom
+
+```
+choom [OPTION] -p pid
+choom [OPTION] -n number -p pid
+choom [OPTION] -n number [--] command [args...]]
+```
+
+Display and adjust OOM-killer score.

src/uu/choom/src/choom.rs

@@ -0,0 +1,97 @@
+// This file is part of the uutils util-linux package.
+//
+// For the full copyright and license information, please view the LICENSE
+// file that was distributed with this source code.
+
+use clap::{crate_version, Arg, ArgAction, ArgGroup, Command};
+use std::io::Write;
+use uucore::{error::UResult, format_usage, help_about, help_usage};
+
+const ABOUT: &str = help_about!("choom.md");
+const USAGE: &str = help_usage!("choom.md");
+
+mod options {
+    pub const PID: &str = "pid";
+    pub const ADJUST: &str = "adjust";
+}
+
+#[cfg(target_os = "linux")]
+#[uucore::main]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
+    let matches: clap::ArgMatches = uu_app().try_get_matches_from(args)?;
+    if let Some(adjust) = matches.get_one::<i32>(options::ADJUST) {
+        let pid = match matches.get_one::<u32>(options::PID) {
+            Some(pid) => *pid,
+            None => std::process::id(),
+        };
+        adjust_oom_score(pid, *adjust)?;
+    } else if let Some(pid) = matches.get_one::<u32>(options::PID) {
+        print_oom_score(*pid)?;
+    }
+
+    Ok(())
+}
+
+pub fn adjust_oom_score(pid: u32, adjust: i32) -> UResult<()> {
+    let path = format!("/proc/{}/oom_score_adj", pid);
+    let mut file = std::fs::OpenOptions::new().write(true).open(path)?;
+    file.write_all(adjust.to_string().as_bytes())?;
+    Ok(())
+}
+
+pub fn print_oom_score(pid: u32) -> UResult<()> {
+    let path = format!("/proc/{}/oom_score", pid);
+    let score = std::fs::read_to_string(path)?;
+    println!("pid {}'s current OOM score: {}", pid, score.trim());
+    let path = format!("/proc/{}/oom_score_adj", pid);
+    let score = std::fs::read_to_string(path)?;
+    println!(
+        "pid {}'s current OOM score adjust value: {}",
+        pid,
+        score.trim()
+    );
+    Ok(())
+}
+
+pub fn uu_app() -> Command {
+    Command::new(uucore::util_name())
+        .version(crate_version!())
+        .about(ABOUT)
+        .override_usage(format_usage(USAGE))
+        .infer_long_args(true)
+        .arg(
+            Arg::new(options::ADJUST)
+                .short('n')
+                .long(options::ADJUST)
+                .help("specify the adjust score value")
+                .action(ArgAction::Set)
+                .value_name("num")
+                .value_parser(clap::value_parser!(i32)),
+        )
+        .arg(
+            Arg::new(options::PID)
+                .short('p')
+                .long(options::PID)
+                .help("process ID")
+                .action(ArgAction::Set)
+                .value_name("num")
+                .value_parser(clap::value_parser!(u32)),
+        )
+        .group(
+            ArgGroup::new("action")
+                .args([options::ADJUST, options::PID])
+                .required(true)
+                .multiple(true),
+        )
+}
+
+#[cfg(not(target_os = "linux"))]
+#[uucore::main]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
+    let _matches: clap::ArgMatches = uu_app().try_get_matches_from(args)?;
+
+    Err(uucore::error::USimpleError::new(
+        1,
+        "`choom` is available only on Linux.",
+    ))
+}

src/uu/choom/src/main.rs

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