Add some basic cli

src/main.rs

@@ -1,3 +1,4 @@
+use clap::Parser;
 use dhcproto::{
     Decodable,
     Decoder,
@@ -13,28 +14,30 @@ use dhcproto::{
 };
 use ipnetwork;
 use pnet;
-use std::{
-    env,
-    net::SocketAddrV6,
-};
+use std::net::SocketAddrV6;
 use tokio::net::UdpSocket;
 
 const ALL_DHCP_RELAY_AGENTS_AND_SERVERS: &str = "ff02::1:2";
 const DHCP_CLIENT_PORT: u16 = 546;
 const DHCP_RELAY_AGENT_AND_SERVER_PORT: u16 = 547;
 
+/// Requests some simple parameters using DHCPv6 from specified network
+#[derive(Parser)]
+#[command(version, about, long_about = None)]
+struct Cli {
+    /// Network interface name used for DHCPv6
+    interface: String,
+}
+
 #[tokio::main]
 async fn main() {
-    let mut args = env::args();
-    args.next(); // Skip executable name
-    // First argument is interface name
-    let interface_name = args.next().expect("No interface name specified");
+    let cli = Cli::parse();
 
     let all_interfaces = pnet::datalink::interfaces();
     let selected_interface = all_interfaces
         .iter()
-        .find(|i| i.name == interface_name)
-        .expect(format!("No interface found with name: {}", interface_name).as_str());
+        .find(|i| i.name == cli.interface)
+        .expect(format!("No interface found with name: {}", cli.interface).as_str());
 
     let ipv6_addresses = selected_interface.ips
         .iter()