colors: respect NO_COLOR spec

Microfetch will now respect the NO_COLOR environment variable if it has
been passed to the program. The performance overhead of this operation
is almost none. In addition, the main function has been updated to lock
stdout.

Cargo.lock

@@ -306,6 +306,12 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
+
 [[package]]
 name = "libc"
 version = "0.2.155"
@@ -330,6 +336,7 @@ version = "0.4.0"
 dependencies = [
  "color-eyre",
  "criterion",
+ "lazy_static",
  "nix",
 ]
 

Cargo.toml

@@ -14,6 +14,7 @@ path = "src/main.rs"
 [dependencies]
 nix = { version = "0.29", features = ["fs", "hostname", "feature"] }
 color-eyre = { version = "0.6", default-features = false }
+lazy_static = "1.5.0"
 
 [dev-dependencies]
 criterion = "0.5"

src/colors.rs

@@ -1,11 +1,57 @@
-pub const RESET: &str = "\x1b[0m";
-pub const BLUE: &str = "\x1b[34m";
-pub const CYAN: &str = "\x1b[36m";
-pub const GREEN: &str = "\x1b[32m";
-pub const YELLOW: &str = "\x1b[33m";
-pub const RED: &str = "\x1b[31m";
-pub const MAGENTA: &str = "\x1b[35m";
+use std::env;
+
+pub struct Colors {
+    pub reset: &'static str,
+    pub blue: &'static str,
+    pub cyan: &'static str,
+    pub green: &'static str,
+    pub yellow: &'static str,
+    pub red: &'static str,
+    pub magenta: &'static str,
+}
+
+impl Colors {
+    const fn new(is_no_color: bool) -> Self {
+        match is_no_color {
+            true => Self {
+                reset: "",
+                blue: "",
+                cyan: "",
+                green: "",
+                yellow: "",
+                red: "",
+                magenta: "",
+            },
+            false => Self {
+                reset: "\x1b[0m",
+                blue: "\x1b[34m",
+                cyan: "\x1b[36m",
+                green: "\x1b[32m",
+                yellow: "\x1b[33m",
+                red: "\x1b[31m",
+                magenta: "\x1b[35m",
+            },
+        }
+    }
+}
+
+lazy_static::lazy_static! {
+    pub static ref COLORS: Colors = {
+        // check for NO_COLOR once at startup
+        let is_no_color = env::var("NO_COLOR").is_ok();
+        Colors::new(is_no_color)
+    };
+}
 
 pub fn print_dots() -> String {
-    format!("{BLUE}  {CYAN}  {GREEN}  {YELLOW}  {RED}  {MAGENTA}  {RESET}")
+    format!(
+        "{}  {}  {}  {}  {}  {}  {}",
+        COLORS.blue,
+        COLORS.cyan,
+        COLORS.green,
+        COLORS.yellow,
+        COLORS.red,
+        COLORS.magenta,
+        COLORS.reset,
+    )
 }

src/main.rs

@@ -4,15 +4,13 @@ mod release;
 mod system;
 mod uptime;
 
-use std::io::Write;
-
-use crate::colors::{print_dots, BLUE, CYAN, RESET};
+use crate::colors::print_dots;
 use crate::desktop::get_desktop_info;
 use crate::release::{get_os_pretty_name, get_system_info};
 use crate::system::{get_memory_usage, get_root_disk_usage, get_shell, get_username_and_hostname};
 use crate::uptime::get_current;
-
 use color_eyre::Report;
+use std::io::Write;
 
 fn main() -> Result<(), Report> {
     color_eyre::install()?;
@@ -56,6 +54,8 @@ struct Fields {
 }
 
 fn print_system_info(fields: &Fields) {
+    use crate::colors::COLORS;
+
     let Fields {
         user_info,
         os_name,
@@ -68,16 +68,22 @@ fn print_system_info(fields: &Fields) {
         colors,
     } = fields;
 
-    let _ = std::io::stdout().write_all(format!(
-        "
- {CYAN}     ▟█▖    {BLUE}▝█▙ ▗█▛          {user_info} ~{RESET}
- {CYAN}  ▗▄▄▟██▄▄▄▄▄{BLUE}▝█▙█▛  {CYAN}▖        {CYAN}  {BLUE}System{RESET}        {os_name}
- {CYAN}  ▀▀▀▀▀▀▀▀▀▀▀▘{BLUE}▝██  {CYAN}▟█▖       {CYAN}  {BLUE}Kernel{RESET}        {kernel_version}
- {BLUE}     ▟█▛       {BLUE}▝█▘{CYAN}▟█▛        {CYAN}  {BLUE}Shell{RESET}         {shell}
- {BLUE}▟█████▛          {CYAN}▟█████▛     {CYAN}  {BLUE}Uptime{RESET}        {uptime}
- {BLUE}   ▟█▛{CYAN}▗█▖       {CYAN}▟█▛          {CYAN}  {BLUE}Desktop{RESET}       {desktop}
- {BLUE}  ▝█▛  {CYAN}██▖{BLUE}▗▄▄▄▄▄▄▄▄▄▄▄       {CYAN}󰍛  {BLUE}Memory{RESET}        {memory_usage}
- {BLUE}   ▝  {CYAN}▟█▜█▖{BLUE}▀▀▀▀▀██▛▀▀▘       {CYAN}󱥎  {BLUE}Storage (/){RESET}   {storage}
- {CYAN}     ▟█▘ ▜█▖    {BLUE}▝█▛          {CYAN}  {BLUE}Colors{RESET}        {colors}
-").as_bytes());
+    let cyan = COLORS.cyan;
+    let blue = COLORS.blue;
+    let reset = COLORS.reset;
+    let system_info = format!("
+    {cyan}     ▟█▖    {blue}▝█▙ ▗█▛          {user_info} ~{reset}
+    {cyan}  ▗▄▄▟██▄▄▄▄▄{blue}▝█▙█▛  {cyan}▖        {cyan}  {blue}System{reset}        {os_name}
+    {cyan}  ▀▀▀▀▀▀▀▀▀▀▀▘{blue}▝██  {cyan}▟█▖       {cyan}  {blue}Kernel{reset}        {kernel_version}
+    {blue}     ▟█▛       {blue}▝█▘{cyan}▟█▛        {cyan}  {blue}Shell{reset}         {shell}
+    {blue}▟█████▛          {cyan}▟█████▛     {cyan}  {blue}Uptime{reset}        {uptime}
+    {blue}   ▟█▛{cyan}▗█▖       {cyan}▟█▛          {cyan}  {blue}Desktop{reset}       {desktop}
+    {blue}  ▝█▛  {cyan}██▖{blue}▗▄▄▄▄▄▄▄▄▄▄▄       {cyan}󰍛  {blue}Memory{reset}        {memory_usage}
+    {blue}   ▝  {cyan}▟█▜█▖{blue}▀▀▀▀▀██▛▀▀▘       {cyan}󱥎  {blue}Storage (/){reset}   {storage}
+    {cyan}     ▟█▘ ▜█▖    {blue}▝█▛          {cyan}  {blue}Colors{reset}        {colors}");
+
+    std::io::stdout()
+        .lock()
+        .write_all(system_info.as_bytes())
+        .expect("Failed to write to stdout");
 }

src/system.rs

@@ -1,14 +1,12 @@
+use crate::colors::COLORS;
 use color_eyre::Result;
 use nix::sys::{statvfs::statvfs, utsname::UtsName};
-
 use std::{
     env,
     fs::File,
     io::{self, Read},
 };
 
-use crate::colors::{CYAN, GREEN, RED, RESET, YELLOW};
-
 pub fn get_username_and_hostname(utsname: &UtsName) -> String {
     let username = env::var("USER").unwrap_or("unknown_user".to_string());
     let hostname = utsname
@@ -16,14 +14,18 @@ pub fn get_username_and_hostname(utsname: &UtsName) -> String {
         .to_str()
         .unwrap_or("unknown_host")
         .to_string();
-
-    format!("{YELLOW}{username}{RED}@{GREEN}{hostname}")
+    format!(
+        "{yellow}{username}{red}@{green}{hostname}{reset}",
+        yellow = COLORS.yellow,
+        red = COLORS.red,
+        green = COLORS.green,
+        reset = COLORS.reset,
+    )
 }
 
 pub fn get_shell() -> String {
     let shell_path = env::var("SHELL").unwrap_or("unknown_shell".to_string());
     let shell_name = shell_path.rsplit('/').next().unwrap_or("unknown_shell");
-
     shell_name.to_string()
 }
 
@@ -32,16 +34,15 @@ pub fn get_root_disk_usage() -> Result<String, io::Error> {
     let block_size = vfs.block_size() as u64;
     let total_blocks = vfs.blocks();
     let available_blocks = vfs.blocks_available();
-
     let total_size = block_size * total_blocks;
     let used_size = total_size - (block_size * available_blocks);
-
     let total_size = total_size as f64 / (1024.0 * 1024.0 * 1024.0);
     let used_size = used_size as f64 / (1024.0 * 1024.0 * 1024.0);
-    let usage = (used_size as f64 / total_size as f64) * 100.0;
-
+    let usage = (used_size / total_size) * 100.0;
     Ok(format!(
-        "{used_size:.2} GiB / {total_size:.2} GiB ({CYAN}{usage:.0}%{RESET})"
+        "{used_size:.2} GiB / {total_size:.2} GiB ({cyan}{usage:.0}%{reset})",
+        cyan = COLORS.cyan,
+        reset = COLORS.reset,
     ))
 }
 
@@ -50,35 +51,31 @@ pub fn get_memory_usage() -> Result<String, io::Error> {
     fn parse_memory_info() -> Result<(f64, f64), io::Error> {
         let mut total_memory_kb = 0.0;
         let mut available_memory_kb = 0.0;
-
         let mut meminfo = String::with_capacity(2048);
         File::open("/proc/meminfo")?.read_to_string(&mut meminfo)?;
-
         for line in meminfo.lines() {
             let mut split = line.split_whitespace();
             match split.next().unwrap_or_default() {
                 "MemTotal:" => total_memory_kb = split.next().unwrap_or("0").parse().unwrap_or(0.0),
                 "MemAvailable:" => {
                     available_memory_kb = split.next().unwrap_or("0").parse().unwrap_or(0.0);
-
                     // MemTotal comes before MemAvailable, stop parsing
                     break;
                 }
                 _ => (),
             }
         }
-
         let total_memory_gb = total_memory_kb / 1024.0 / 1024.0;
         let available_memory_gb = available_memory_kb / 1024.0 / 1024.0;
         let used_memory_gb = total_memory_gb - available_memory_gb;
-
         Ok((used_memory_gb, total_memory_gb))
     }
 
     let (used_memory, total_memory) = parse_memory_info()?;
     let percentage_used = (used_memory / total_memory * 100.0).round() as u64;
-
     Ok(format!(
-        "{used_memory:.2} GiB / {total_memory:.2} GiB ({CYAN}{percentage_used}%{RESET})"
+        "{used_memory:.2} GiB / {total_memory:.2} GiB ({cyan}{percentage_used}%{reset})",
+        cyan = COLORS.cyan,
+        reset = COLORS.reset,
     ))
 }