From 7855dde91e5d08b0183c8c8f266fd7ea54807d3f Mon Sep 17 00:00:00 2001
From: Milo Turner <iitalics@gmail.com>
Date: Mon, 2 Mar 2020 16:06:39 -0500
Subject: [PATCH] command line argument parsing for recv

---
 hptp-recv/src/main.rs | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/hptp-recv/src/main.rs b/hptp-recv/src/main.rs
index 1d2e115..122188c 100644
--- a/hptp-recv/src/main.rs
+++ b/hptp-recv/src/main.rs
@@ -1,5 +1,28 @@
 extern crate hptp;
 
-fn main() {
-    println!("{}", hptp::RECV_GREETING);
+#[derive(Debug)]
+struct Hostname(String, u16);
+
+fn go(hn: Hostname) {
+    println!("{:?}", hn)
+}
+
+fn usage() {
+    print!("usage:\n./3700recv <host-ip>:<host-port>\n")
+}
+
+fn parse_args() -> Result<Hostname, ()> {
+    let mut args = std::env::args();
+    let arg = args.nth(1).ok_or(())?;
+    let i = arg.find(':').ok_or(())?;
+    let ip: String = arg[..i].into();
+    let port: u16 = arg[i + 1..].parse::<u16>().map_err(|_| ())?;
+    Ok(Hostname(ip, port))
+}
+
+fn main() {
+    match parse_args() {
+        Ok(x) => go(x),
+        Err(_) => usage(),
+    }
 }