feat(sysctl): print the parameters with their section colors

Cargo.lock

@@ -11,6 +11,17 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "atty"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
+dependencies = [
+ "hermit-abi",
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.0.1"
@@ -44,6 +55,17 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "colored"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b3616f750b84d8f0de8a58bda93e08e2a81ad3f523089b05f1dffecab48c6cbd"
+dependencies = [
+ "atty",
+ "lazy_static",
+ "winapi",
+]
+
 [[package]]
 name = "crossbeam-channel"
 version = "0.5.1"
@@ -324,6 +346,7 @@ dependencies = [
 name = "systeroid-core"
 version = "0.1.0"
 dependencies = [
+ "colored",
  "lazy_static",
  "rayon",
  "sysctl",

systeroid-core/Cargo.toml

@@ -9,6 +9,7 @@ sysctl = "0.4.2"
 thiserror = "1.0.29"
 lazy_static = "1.4.0"
 rayon = "1.5.1"
+colored = "2.0.0"
 
 [dependencies.systeroid-parser]
 version = "0.1.0"

systeroid-core/src/config.rs

@@ -0,0 +1,46 @@
+use crate::sysctl::Section;
+use colored::Color;
+use std::collections::HashMap;
+
+/* Macro for the concise initialization of HashMap */
+macro_rules! map {
+    ($( $key: expr => $val: expr ),*) => {{
+         let mut map = ::std::collections::HashMap::new();
+         $( map.insert($key, $val); )*
+         map
+    }}
+}
+
+/// General configuration.
+#[derive(Debug, Default)]
+pub struct Config {
+    /// Sysctl configuration.
+    pub sysctl: SysctlConfig,
+}
+
+/// Sysctl configuration.
+#[derive(Debug)]
+pub struct SysctlConfig {
+    /// Sections and the corresponding colors.
+    pub section_colors: HashMap<Section, Color>,
+    /// Default color for the output
+    pub default_color: Color,
+}
+
+impl Default for SysctlConfig {
+    fn default() -> Self {
+        Self {
+            section_colors: map! {
+                Section::Abi => Color::Red,
+                Section::Fs => Color::Green,
+                Section::Kernel => Color::Magenta,
+                Section::Net => Color::Blue,
+                Section::Sunrpc => Color::Yellow,
+                Section::User => Color::Cyan,
+                Section::Vm => Color::BrightRed,
+                Section::Unknown => Color::BrightBlack
+            },
+            default_color: Color::BrightBlack,
+        }
+    }
+}

systeroid-core/src/lib.rs

@@ -13,3 +13,6 @@ pub mod error;
 
 /// Parsers for the kernel documentation.
 pub mod parsers;
+
+/// Configuration.
+pub mod config;

systeroid-core/src/sysctl.rs

@@ -1,5 +1,7 @@
+use crate::config::SysctlConfig;
 use crate::error::Result;
 use crate::parsers::parse_kernel_docs;
+use colored::*;
 use rayon::prelude::*;
 use std::fmt::{self, Display, Formatter};
 use std::io::Write;
@@ -9,7 +11,7 @@ use sysctl::{CtlFlags, CtlIter, Sysctl as SysctlImpl};
 use systeroid_parser::document::Document;
 
 /// Sections of the sysctl documentation.
-#[derive(Clone, Copy, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 pub enum Section {
     /// Documentation for `/proc/sys/abi/*`
     Abi,
@@ -87,16 +89,44 @@ pub struct Parameter {
     pub document: Option<Document>,
 }
 
+impl Parameter {
+    /// Returns the parameter name with corresponding section colors.
+    pub fn colored_name(&self, config: &SysctlConfig) -> String {
+        let fields = self.name.split('.').collect::<Vec<&str>>();
+        fields
+            .iter()
+            .enumerate()
+            .fold(String::new(), |mut result, (i, v)| {
+                if i != fields.len() - 1 {
+                    let section_color = *(config
+                        .section_colors
+                        .get(&self.section)
+                        .unwrap_or(&config.default_color));
+                    result += &format!(
+                        "{}{}",
+                        v.color(section_color),
+                        ".".color(config.default_color)
+                    );
+                } else {
+                    result += v;
+                }
+                result
+            })
+    }
+}
+
 /// Sysctl wrapper for managing the kernel parameters.
 #[derive(Debug)]
 pub struct Sysctl {
     /// Available kernel parameters.
     pub parameters: Vec<Parameter>,
+    /// Configuration.
+    pub config: SysctlConfig,
 }
 
 impl Sysctl {
     /// Constructs a new instance by fetching the available kernel parameters.
-    pub fn init() -> Result<Self> {
+    pub fn init(config: SysctlConfig) -> Result<Self> {
         let mut parameters = Vec::new();
         for ctl in CtlIter::root().filter_map(StdResult::ok).filter(|ctl| {
             ctl.flags()
@@ -111,7 +141,7 @@ impl Sysctl {
                 document: None,
             });
         }
-        Ok(Self { parameters })
+        Ok(Self { parameters, config })
     }
 
     /// Updates the descriptions of the kernel parameters.
@@ -146,9 +176,19 @@ impl Sysctl {
     }
 
     /// Prints the available kernel parameters to the given output.
-    pub fn print_all<W: Write>(&self, output: &mut W) -> Result<()> {
+    pub fn print_all<W: Write>(&self, output: &mut W, colored: bool) -> Result<()> {
         for parameter in &self.parameters {
-            writeln!(output, "{} = {}", parameter.name, parameter.value)?;
+            if colored {
+                writeln!(
+                    output,
+                    "{} {} {}",
+                    parameter.colored_name(&self.config),
+                    "=".color(self.config.default_color),
+                    parameter.value.bold(),
+                )?;
+            } else {
+                writeln!(output, "{} = {}", parameter.name, parameter.value)?;
+            }
         }
         Ok(())
     }

systeroid/src/args.rs

@@ -19,6 +19,8 @@ pub struct Args {
     pub kernel_docs: Option<PathBuf>,
     /// Display all of the kernel parameters.
     pub all: bool,
+    /// Disable colored output.
+    pub no_color: bool,
 }
 
 impl Args {
@@ -28,6 +30,7 @@ impl Args {
         opts.optflag("h", "help", "display this help and exit");
         opts.optflag("V", "version", "output version information and exit");
         opts.optflag("a", "all", "display all variables");
+        opts.optflag("", "no-color", "disable colored output");
         opts.optopt(
             "d",
             "docs",
@@ -55,6 +58,7 @@ impl Args {
             Some(Args {
                 kernel_docs: matches.opt_str("d").map(PathBuf::from),
                 all: matches.opt_present("a"),
+                no_color: matches.opt_present("no-color"),
             })
         }
     }

systeroid/src/lib.rs

@@ -7,20 +7,22 @@ pub mod args;
 
 use crate::args::Args;
 use std::io;
+use systeroid_core::config::Config;
 use systeroid_core::error::Result;
 use systeroid_core::sysctl::Sysctl;
 
 /// Runs `systeroid`.
 pub fn run(args: Args) -> Result<()> {
+    let config = Config::default();
     let mut stdout = io::stdout();
-    let mut sysctl = Sysctl::init()?;
+    let mut sysctl = Sysctl::init(config.sysctl)?;
 
     if let Some(kernel_docs) = args.kernel_docs {
         sysctl.update_docs(&kernel_docs)?;
     }
 
     if args.all {
-        sysctl.print_all(&mut stdout)?;
+        sysctl.print_all(&mut stdout, !args.no_color)?;
     }
 
     Ok(())