init commit

2026-03-09 23:09:46 -04:00
parent 5cbc493cc5
commit 5da77e3360
73 changed files with 9935 additions and 103 deletions
@@ -0,0 +1,131 @@
+;;; TCP Chat Server — multi-terminal chat using gen_tcp
+;;;
+;;; Start the server:
+;;;   mix clje.run --no-halt examples/tcp_chat_server.clje
+;;;
+;;; Then connect clients in separate terminals:
+;;;   mix clje.run --no-halt examples/tcp_chat_client.clje -- alice
+;;;   mix clje.run --no-halt examples/tcp_chat_client.clje -- bob
+;;;
+;;; Protocol (line-based):
+;;;   Client → Server:  JOIN:<username> | MSG:<text> | QUIT
+;;;   Server → Client:  SYS:<text> | MSG:<user>:<text> | JOIN:<user> | QUIT:<user>
+
+(ns TcpChatServer
+  (:require [clje.core :refer :all]
+            [Map] [String] [gen_tcp] [inet]))
+
+;; ── Room manager ──────────────────────────────────────────────────
+;; Holds {username → socket} map, broadcasts messages to all members.
+
+(defn room-loop [members]
+  (receive
+    [:join username socket handler-pid]
+      (do
+        (TcpChatServer/broadcast members (str "JOIN:" username "\n"))
+        (TcpChatServer/send-line socket (str "SYS:Welcome " username "! " (count members) " user(s) online.\n"))
+        (TcpChatServer/room-loop (assoc members username #el[socket handler-pid])))
+
+    [:msg username text]
+      (do
+        (TcpChatServer/broadcast members (str "MSG:" username ":" text "\n"))
+        (TcpChatServer/room-loop members))
+
+    [:quit username]
+      (let [new-members (dissoc members username)]
+        (TcpChatServer/broadcast new-members (str "QUIT:" username "\n"))
+        (TcpChatServer/room-loop new-members))
+
+    [:list reply-pid]
+      (do
+        (send reply-pid #el[:members (Map/keys members)])
+        (TcpChatServer/room-loop members))))
+
+(defn broadcast [members line]
+  (doseq [[_name [socket _pid]] members]
+    (gen_tcp/send socket line)))
+
+(defn send-line [socket line]
+  (gen_tcp/send socket line))
+
+;; ── Per-client handler ────────────────────────────────────────────
+;; Receives TCP data via active mode and forwards to room manager.
+
+(defn client-handler [socket room username]
+  (receive
+    [:tcp _sock data]
+      (let [line (String/trim data)]
+        (cond
+          (String/starts-with? line "MSG:")
+            (do
+              (send room #el[:msg username (String/slice line 4 (String/length line))])
+              (TcpChatServer/client-handler socket room username))
+
+          (== line "QUIT")
+            (do
+              (send room #el[:quit username])
+              (gen_tcp/close socket)
+              (println (str "  [" username " quit]")))
+
+          :else
+            (do
+              (TcpChatServer/send-line socket (str "SYS:Unknown command. Send MSG:<text> or QUIT\n"))
+              (TcpChatServer/client-handler socket room username))))
+
+    [:tcp_closed _sock]
+      (do
+        (send room #el[:quit username])
+        (println (str "  [" username " disconnected]")))
+
+    [:tcp_error _sock _reason]
+      (do
+        (send room #el[:quit username])
+        (println (str "  [" username " error]")))))
+
+;; ── Accept loop ───────────────────────────────────────────────────
+
+(defn accept-loop [listen-socket room]
+  (case (gen_tcp/accept listen-socket)
+    [:ok client-socket]
+      (do
+        (TcpChatServer/handle-new-client client-socket room)
+        (TcpChatServer/accept-loop listen-socket room))
+    [:error reason]
+      (println (str "Accept error: " reason))))
+
+(defn handle-new-client [socket room]
+  ;; First message must be JOIN:<username>
+  ;; Socket starts in passive mode so we can recv synchronously
+  (case (gen_tcp/recv socket 0 5000)
+    [:ok data]
+      (let [line (String/trim data)]
+        (if (String/starts-with? line "JOIN:")
+          (let [username (String/slice line 5 (String/length line))
+                ;; Switch to active mode for the handler
+                _ (inet/setopts socket (list #el[:active true]))
+                handler (spawn (fn []
+                          (TcpChatServer/client-handler socket room username)))]
+            (gen_tcp/controlling-process socket handler)
+            (send room #el[:join username socket handler])
+            (println (str "  [" username " connected]")))
+          (do
+            (TcpChatServer/send-line socket "SYS:First message must be JOIN:<username>\n")
+            (gen_tcp/close socket))))
+    [:error _reason]
+      (gen_tcp/close socket)))
+
+;; ── Start ─────────────────────────────────────────────────────────
+
+(defn start [port]
+  (case (gen_tcp/listen port (list :binary #el[:active false] #el[:packet :line] #el[:reuseaddr true]))
+    [:ok listen-socket]
+      (do
+        (println (str "TCP Chat Server listening on port " port))
+        (println "Connect with: mix clje.run --no-halt examples/tcp_chat_client.clje -- <username>")
+        (let [room (spawn (fn [] (TcpChatServer/room-loop {})))]
+          (TcpChatServer/accept-loop listen-socket room)))
+    [:error reason]
+      (println (str "Failed to listen on port " port ": " reason))))
+
+;; Start the server on port 4040
+(TcpChatServer/start 4040)