feat: cli argument parsing

src/main.rs

@@ -1,3 +1,46 @@
-fn main() {
-    println!("Hello, world!");
+use std::ffi::c_int;
+use std::process;
+use std::convert::From;
+use std::path::PathBuf;
+use signal_hook::consts::signal::*;
+
+use clap::{Parser, ValueEnum};
+use anyhow;
+
+#[derive(Parser, Clone, ValueEnum)]
+pub enum HandledSignals {
+    SIGHUP,
+    SIGUSR1,
+    SIGUSR2,
+}
+
+impl From<HandledSignals> for c_int {
+    fn from(value: HandledSignals) -> Self {
+        match value {
+            HandledSignals::SIGHUP => SIGHUP,
+            HandledSignals::SIGUSR1 => SIGUSR1,
+            HandledSignals::SIGUSR2 => SIGUSR2,
+        }
+    }
+}
+
+#[derive(Parser)]
+#[command(version, about, long_about = None)]
+struct Args {
+    #[arg(short = 'e', long = "err-path", help="Path to write stderr to")]
+    std_err_path: PathBuf,
+    #[arg(short = 'o', long = "out-path", help="Path to write stdout to")]
+    std_out_path: PathBuf,
+    #[arg(long = "sig", value_enum, help="Optional signal notifiying that the file paths have been rotated")]
+    rotated_signal: Option<HandledSignals>,
+    #[arg(long="size", help="Optional size at which to rotate the files")]
+    rotate_size_bytes: Option<usize>,
+    #[arg(last = true, help="Command to run")]
+    cmd: Vec<String>,
+}
+
+fn main() -> anyhow::Result<()> {
+    let args = Args::parse();
+    println!("Hello, world!");
+    return Ok(());
 }