feat: add TFTP server and client binaries

src/main.rs

@@ -1,3 +1,110 @@
+use std::{net::SocketAddr, path::PathBuf, time::Duration};
+
+use pfs_tftp_sync::{Server, ServerConfig};
+
 fn main() {
-    println!("Hello, world!");
+    match run() {
+        Ok(()) => {}
+        Err(e) => {
+            eprintln!("{e}");
+            std::process::exit(2);
+        }
+    }
+}
+
+fn run() -> Result<(), String> {
+    let mut cfg = ServerConfig::default();
+
+    let mut args = std::env::args().skip(1);
+    while let Some(arg) = args.next() {
+        match arg.as_str() {
+            "--help" | "-h" => {
+                print_usage();
+                return Ok(());
+            }
+            "--bind" => {
+                let value = next_value(&mut args, "--bind")?;
+                cfg.bind = value.parse::<SocketAddr>().map_err(|e| format!("{e}"))?;
+            }
+            "--root" => {
+                let value = next_value(&mut args, "--root")?;
+                cfg.root = PathBuf::from(value);
+            }
+            "--allow-write" => cfg.allow_write = true,
+            "--overwrite" => cfg.overwrite = true,
+            "--timeout-ms" => {
+                let value = next_value(&mut args, "--timeout-ms")?;
+                cfg.timeout = Duration::from_millis(parse_u64("--timeout-ms", &value)?);
+            }
+            "--retries" => {
+                let value = next_value(&mut args, "--retries")?;
+                cfg.retries = parse_u32("--retries", &value)?;
+            }
+            "--dally-timeout-ms" => {
+                let value = next_value(&mut args, "--dally-timeout-ms")?;
+                cfg.dally_timeout = Duration::from_millis(parse_u64("--dally-timeout-ms", &value)?);
+            }
+            "--dally-retries" => {
+                let value = next_value(&mut args, "--dally-retries")?;
+                cfg.dally_retries = parse_u32("--dally-retries", &value)?;
+            }
+            other => return Err(format!("unknown argument: {other}")),
+        }
+    }
+
+    eprintln!(
+        "Serving TFTP on {} (root: {}, allow_write: {}, overwrite: {})",
+        cfg.bind,
+        cfg.root.display(),
+        cfg.allow_write,
+        cfg.overwrite
+    );
+
+    Server::new(cfg)
+        .serve()
+        .map_err(|e| format!("server error: {e}"))?;
+
+    Ok(())
+}
+
+fn next_value(
+    args: &mut impl Iterator<Item = String>,
+    flag: &'static str,
+) -> Result<String, String> {
+    args.next()
+        .ok_or_else(|| format!("{flag} requires a value"))
+}
+
+fn parse_u64(flag: &'static str, value: &str) -> Result<u64, String> {
+    value
+        .parse::<u64>()
+        .map_err(|e| format!("{flag}: invalid value: {e}"))
+}
+
+fn parse_u32(flag: &'static str, value: &str) -> Result<u32, String> {
+    value
+        .parse::<u32>()
+        .map_err(|e| format!("{flag}: invalid value: {e}"))
+}
+
+fn print_usage() {
+    eprintln!(
+        "\
+pfs-tftp (server)
+
+USAGE:
+    pfs-tftp [OPTIONS]
+
+OPTIONS:
+    --bind <IP:PORT>           Bind address (default: 0.0.0.0:6969)
+    --root <DIR>               Root directory (default: .)
+    --allow-write              Enable WRQ (default: disabled)
+    --overwrite                Allow overwriting existing files (default: disabled)
+    --timeout-ms <MILLIS>      Packet timeout (default: 5000)
+    --retries <N>              Retransmit attempts (default: 5)
+    --dally-timeout-ms <MILLIS>Wait time for duplicate final DATA (default: timeout)
+    --dally-retries <N>        Dally attempts (default: 2)
+    --help, -h                 Show this help
+"
+    );
 }