Add nproc applet

Cargo.lock

@@ -172,6 +172,16 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ffbee8634e0d45d258acb448e7eaab3fce7a0a467395d4d9f228e3c1f01fb2e4"
 
+[[package]]
+name = "num_cpus"
+version = "1.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fac9e2da13b5eb447a6ce3d392f23a29d8694bff781bf03a16cd9ac8697593b"
+dependencies = [
+ "hermit-abi 0.2.6",
+ "libc",
+]
+
 [[package]]
 name = "os_str_bytes"
 version = "6.4.1"
@@ -210,6 +220,7 @@ dependencies = [
  "data-encoding",
  "hostname",
  "libc",
+ "num_cpus",
  "termcolor",
 ]
 

Cargo.toml

@@ -14,6 +14,7 @@ clap_mangen = "0.2.5"
 data-encoding = "2.3.3"
 hostname = { version = "0.3", features = ["set"] }
 libc = "0.2.139"
+num_cpus = "1.15.0"
 termcolor = "1.1.3"
 
 [profile.release]

src/cmd/mod.rs

@@ -21,6 +21,7 @@ mod ls;
 pub mod mountpoint;
 mod mv;
 pub mod nologin;
+pub mod nproc;
 mod pwd;
 pub mod rev;
 mod rm;
@@ -34,7 +35,7 @@ pub mod yes;
 pub use {
     self::hostname::Hostname, base32::Base32, base64::Base64, bootstrap::Bootstrap,
     dirname::Dirname, echo::Echo, factor::Factor, head::Head, mountpoint::Mountpoint,
-    nologin::Nologin, r#false::False, r#true::True, rev::Rev, shitbox::Shitbox, sleep::Sleep,
+    nologin::Nologin, nproc::Nproc, r#false::False, r#true::True, rev::Rev, shitbox::Shitbox, sleep::Sleep,
     yes::Yes,
 };
 
@@ -57,6 +58,7 @@ pub fn get(name: &str) -> Option<Box<dyn Cmd>> {
         "head" => Some(Box::new(Head::default())),
         "mountpoint" => Some(Box::new(Mountpoint::default())),
         "nologin" => Some(Box::new(Nologin::default())),
+        "nproc" => Some(Box::new(Nproc::default())),
         "rev" => Some(Box::new(Rev::default())),
         "shitbox" => Some(Box::new(Shitbox::default())),
         "sleep" => Some(Box::new(Sleep::default())),
@@ -66,7 +68,7 @@ pub fn get(name: &str) -> Option<Box<dyn Cmd>> {
     }
 }
 
-pub static COMMANDS: [&'static str; 16] = [
+pub static COMMANDS: [&'static str; 17] = [
     "base32",
     "base64",
     "bootstrap",
@@ -78,6 +80,7 @@ pub static COMMANDS: [&'static str; 16] = [
     "hostname",
     "mountpoint",
     "nologin",
+    "nproc",
     "rev",
     "sleep",
     "shitbox",

src/cmd/nproc/mod.rs

@@ -0,0 +1,53 @@
+use clap::{Arg, Command, ArgAction};
+use std::io;
+use super::Cmd;
+
+#[derive(Debug)]
+pub struct Nproc {
+    name: &'static str,
+    path: Option<crate::Path>,
+}
+
+impl Default for Nproc {
+    fn default() -> Self {
+        Self {
+            name: "nproc",
+            path: Some(crate::Path::UsrBin),
+        }
+    }
+}
+
+impl Cmd for Nproc {
+    fn name(&self) -> &str {
+        self.name
+    }
+
+    fn cli(&self) -> clap::Command {
+        Command::new(self.name)
+            .author("Nathan Fisher")
+            .about("Print the number of processing units available")
+            .arg(
+                Arg::new("ALL")
+                    .help("Print the number of installed processors")
+                    .short('a')
+                    .long("all")
+                    .action(ArgAction::SetTrue),
+            )
+    }
+
+    fn run(&self, matches: Option<&clap::ArgMatches>) -> Result<(), Box<dyn std::error::Error>> {
+        let Some(matches) = matches else {
+            return Err(Box::new(io::Error::new(io::ErrorKind::Other, "no input")));
+        };
+        if matches.get_flag("ALL") {
+            println!("{}", num_cpus::get());
+        } else {
+            println!("{}", num_cpus::get_physical());
+        }
+        Ok(())
+    }
+
+    fn path(&self) -> Option<crate::Path> {
+        self.path
+    }
+}