added --interface flag

1 files changed, 15 insertions, 5 deletions

diff --git a/src/main.rs b/src/main.rs
index 819d656..277d8ea 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -24,6 +24,9 @@ struct Cli {
     #[clap(long)]
     hostname: Option<String>,
 
+    #[clap(long)]
+    interface: Option<String>,
+
     #[clap(long, default_value = "0.0.0.0")]
     listen_address: Ipv4Addr,
 
@@ -58,7 +61,14 @@ fn main() {
                 .expect("unable to convert local machine's hostname to utf-8 string")
         }
     };
-    let local_ip_address = if cli.listen_address == Ipv4Addr::UNSPECIFIED {
+    let local_ip_address = if let Some(interface_name) = cli.interface {
+        let interfaces = list_network_interfaces().expect("unable to list network interfaces");
+        let interface = interfaces
+            .iter()
+            .find(|i| i.interface == interface_name)
+            .expect("interface not found");
+        interface.address
+    } else if cli.listen_address == Ipv4Addr::UNSPECIFIED {
         let interfaces = list_network_interfaces().expect("unable to list network interfaces");
         let mut chosen = None;
         for interface in interfaces {
@@ -238,10 +248,10 @@ fn handle_packet_4011(context: &Context, buf: &[u8], socket: &UdpSocket, sender_
         if let DhcpOption::VendorClassIdentifier(vendor_class) = option
             && let Ok(dhcp::PxeClassIdentifier::Client(class)) =
                 dhcp::PxeClassIdentifier::try_from(vendor_class.as_slice())
-            {
-                println!("{class}");
-                client_class = Some(class);
-            }
+        {
+            println!("{class}");
+            client_class = Some(class);
+        }
     }
     let client_class = match client_class {
         Some(class) => class,