--- lbbs/src/net_server.c	2025/11/04 13:49:51	1.77
+++ lbbs/src/net_server.c	2025/11/05 04:19:21	1.79
@@ -3,7 +3,7 @@
  * net_server
  *   - network server with SSH support
  *
- * Copyright (C) 2004-2025 by Leaflet <leaflet@leafok.com>
+ * Copyright (C) 2004-2025  Leaflet <leaflet@leafok.com>
  */
 
 #include "bbs.h"
@@ -39,8 +39,13 @@
 #include <sys/wait.h>
 #include <systemd/sd-daemon.h>
 
-#define WAIT_CHILD_PROCESS_EXIT_TIMEOUT 5 // second
-#define WAIT_CHILD_PROCESS_KILL_TIMEOUT 1 // second
+enum _net_server_constant_t
+{
+	WAIT_CHILD_PROCESS_EXIT_TIMEOUT = 5, // second
+	WAIT_CHILD_PROCESS_KILL_TIMEOUT = 1, // second
+
+	SSH_AUTH_MAX_DURATION = 60 * 1000, // milliseconds
+};
 
 struct process_sockaddr_t
 {
@@ -51,9 +56,7 @@ typedef struct process_sockaddr_t PROCES
 
 static PROCESS_SOCKADDR process_sockaddr_pool[MAX_CLIENT_LIMIT];
 
-#define SSH_AUTH_MAX_DURATION (60 * 1000) // milliseconds
-
-#define SFTP_SERVER_PATH "/usr/lib/sftp-server"
+static const char SFTP_SERVER_PATH[] = "/usr/lib/sftp-server";
 
 /* A userdata struct for session. */
 struct session_data_struct