Added argument for piping log to file

.gitignore

@@ -1 +1,2 @@
 /target
+*.log

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "strain"
-version = "0.0.5"
+version = "0.0.6"
 edition = "2021"
 description = "A CPU stressing utility written in Rust"
 license = "GPL-3.0-or-later"

src/args.rs

@@ -1,4 +1,4 @@
-use std::str::FromStr;
+use std::{path::PathBuf, str::FromStr};
 
 use clap::Parser;
 
@@ -38,6 +38,10 @@ pub struct StrainArgs {
     /// Mandelbrot set maximum iterations
     #[arg(short = 'I', long, default_value_t = 1_000_000)]
     pub mandelbrot_iterations: usize,
+
+    /// Write logs to file
+    #[arg(short = 'L', long)]
+    pub log_file: Option<PathBuf>,
 }
 
 #[derive(Debug, Copy, Clone)]

src/main.rs

@@ -7,16 +7,19 @@ use crate::{
 };
 use clap::Parser;
 use log::LevelFilter;
-use std::{io::Write, str::FromStr, time::SystemTime};
+use std::{io::Write, path::PathBuf, str::FromStr, time::SystemTime};
 
 pub mod args;
 pub mod lucas_lehmer;
 pub mod mandelbrot;
 pub mod rsa;
 pub mod stress;
 
-fn setup_logger(log_level: log::LevelFilter) -> Result<(), fern::InitError> {
-    fern::Dispatch::new()
+fn setup_logger(
+    log_level: log::LevelFilter,
+    log_file: Option<PathBuf>,
+) -> Result<(), fern::InitError> {
+    let mut dispatch = fern::Dispatch::new()
         .format(|out, message, record| {
             out.finish(format_args!(
                 "[{} {} {}] {}",
@@ -27,18 +30,27 @@ fn setup_logger(log_level: log::LevelFilter) -> Result<(), fern::InitError> {
             ))
         })
         .level(log_level)
-        .chain(std::io::stdout())
-        .apply()?;
+        .chain(std::io::stdout());
+
+    if let Some(path) = log_file {
+        let file = std::fs::File::create(path).expect("Failed to create log file");
+        dispatch = dispatch.chain(file);
+    }
+
+    dispatch.apply()?;
     Ok(())
 }
 
 fn main() {
     let args = StrainArgs::parse();
-    setup_logger(if args.debug {
-        LevelFilter::Debug
-    } else {
-        LevelFilter::Info
-    })
+    setup_logger(
+        if args.debug {
+            LevelFilter::Debug
+        } else {
+            LevelFilter::Info
+        },
+        args.log_file,
+    )
     .expect("Failed to setup logger");
 
     if args.list_strategies {