From 8348f2dc1faf6c27038e84a7d305fef3aed6edfb Mon Sep 17 00:00:00 2001
From: tali <iitalics@gmail.com>
Date: Tue, 30 Jan 2024 21:37:30 -0500
Subject: [PATCH] respond to client PING messages

---
 lib/server/connection.ml | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/lib/server/connection.ml b/lib/server/connection.ml
index 1cb3227..35f90e7 100644
--- a/lib/server/connection.ml
+++ b/lib/server/connection.ml
@@ -541,6 +541,21 @@ let on_msg_motd t =
   motd t;
   Ok ()
 
+let on_msg_ping t token =
+  let* _me = require_registered t in
+  match token with
+  | None -> Ok ()
+  | Some token ->
+    let prefix = Server_info.prefix t.server_info in
+    Outbox.send t.outbox
+      (Msg.make ~prefix "PONG" [t.server_info.hostname; token]
+         ~always_trailing:true);
+    Ok ()
+
+let on_msg_pong t _token =
+  let* _me = require_registered t in
+  Ok ()
+
 let welcome t me =
   let whoami = Msg.prefix_string (User.prefix me) in
   let s_hostname = t.server_info.hostname in
@@ -655,6 +670,8 @@ let dispatch t = function
   | "USER", unm :: _ :: _ :: rnm :: _ -> on_msg_user t unm rnm
   | "QUIT", reason -> on_msg_quit t (concat_args reason)
   | "MOTD", _ -> on_msg_motd t
+  | "PING", args -> on_msg_ping t (concat_args args)
+  | "PONG", args -> on_msg_pong t (concat_args args)
   | "PRIVMSG", ([] | "" :: _) -> Error norecipient
   | "PRIVMSG", ([_] | _ :: "" :: _) -> Error notexttosend
   | "PRIVMSG", tgt :: msg :: _ -> on_msg_privmsg t tgt msg