File 0011-vnc-server-Hook-up-VNC-server-to-the-throttler.patch of Package gnome-remote-desktop

From aea108e613c18567ea1bd3bce753aaf013d5fb1e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20=C3=85dahl?= <jadahl@gmail.com>
Date: Fri, 30 May 2025 16:55:46 +0200
Subject: [PATCH 11/13] vnc-server: Hook up VNC server to the throttler

This allows us to replace existing single session limitation with
limiting the throttler to one accepted connection at any given time.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-remote-desktop/-/merge_requests/321>
---
 src/grd-session-vnc.c |  2 ++
 src/grd-vnc-server.c  | 48 +++++++++++++++++++++++++++++++------------
 2 files changed, 37 insertions(+), 13 deletions(-)

diff --git a/src/grd-session-vnc.c b/src/grd-session-vnc.c
index f7e1408..7cd41e9 100644
--- a/src/grd-session-vnc.c
+++ b/src/grd-session-vnc.c
@@ -34,6 +34,7 @@
 #include "grd-prompt.h"
 #include "grd-settings.h"
 #include "grd-stream.h"
+#include "grd-utils.h"
 #include "grd-vnc-server.h"
 #include "grd-vnc-pipewire-stream.h"
 
@@ -827,6 +828,7 @@ grd_session_vnc_stop (GrdSession *session)
 
   grd_session_vnc_detach_source (session_vnc);
 
+  grd_close_connection_and_notify (session_vnc->connection);
   g_clear_object (&session_vnc->connection);
   g_clear_object (&session_vnc->clipboard_vnc);
   g_clear_pointer (&session_vnc->rfb_screen->frameBuffer, g_free);
diff --git a/src/grd-vnc-server.c b/src/grd-vnc-server.c
index 8322065..4cfbcad 100644
--- a/src/grd-vnc-server.c
+++ b/src/grd-vnc-server.c
@@ -30,6 +30,7 @@
 #include "grd-context.h"
 #include "grd-debug.h"
 #include "grd-session-vnc.h"
+#include "grd-throttler.h"
 #include "grd-utils.h"
 
 enum
@@ -43,6 +44,8 @@ struct _GrdVncServer
 {
   GSocketService parent;
 
+  GrdThrottler *throttler;
+
   GList *sessions;
 
   GList *stopped_sessions;
@@ -53,6 +56,11 @@ struct _GrdVncServer
 
 G_DEFINE_TYPE (GrdVncServer, grd_vnc_server, G_TYPE_SOCKET_SERVICE)
 
+static void
+allow_connection_cb (GrdThrottler      *throttler,
+                     GSocketConnection *connection,
+                     gpointer           user_data);
+
 GrdContext *
 grd_vnc_server_get_context (GrdVncServer *vnc_server)
 {
@@ -103,22 +111,15 @@ on_session_stopped (GrdSession *session, GrdVncServer *vnc_server)
     }
 }
 
-static gboolean
-on_incoming (GSocketService    *service,
-             GSocketConnection *connection)
+static void
+allow_connection_cb (GrdThrottler      *throttler,
+                     GSocketConnection *connection,
+                     gpointer           user_data)
 {
-  GrdVncServer *vnc_server = GRD_VNC_SERVER (service);
+  GrdVncServer *vnc_server = GRD_VNC_SERVER (user_data);
   GrdSessionVnc *session_vnc;
 
-  g_debug ("New incoming VNC connection");
-
-  if (vnc_server->sessions)
-    {
-      /* TODO: Add the rfbScreen instance to GrdVncServer to support multiple
-       * sessions. */
-      g_message ("Refusing new VNC connection: already an active session");
-      return TRUE;
-    }
+  g_debug ("Creating new VNC session");
 
   session_vnc = grd_session_vnc_new (vnc_server, connection);
   vnc_server->sessions = g_list_append (vnc_server->sessions, session_vnc);
@@ -126,7 +127,16 @@ on_incoming (GSocketService    *service,
   g_signal_connect (session_vnc, "stopped",
                     G_CALLBACK (on_session_stopped),
                     vnc_server);
+}
 
+static gboolean
+on_incoming (GSocketService    *service,
+             GSocketConnection *connection)
+{
+  GrdVncServer *vnc_server = GRD_VNC_SERVER (service);
+
+  grd_throttler_handle_connection (vnc_server->throttler,
+                                   connection);
   return TRUE;
 }
 
@@ -187,6 +197,8 @@ grd_vnc_server_stop (GrdVncServer *vnc_server)
   grd_vnc_server_cleanup_stopped_sessions (vnc_server);
   g_clear_handle_id (&vnc_server->cleanup_sessions_idle_id,
                      g_source_remove);
+
+  g_clear_object (&vnc_server->throttler);
 }
 
 static void
@@ -235,6 +247,7 @@ grd_vnc_server_dispose (GObject *object)
   g_assert (!vnc_server->sessions);
   g_assert (!vnc_server->stopped_sessions);
   g_assert (!vnc_server->cleanup_sessions_idle_id);
+  g_assert (!vnc_server->throttler);
 
   G_OBJECT_CLASS (grd_vnc_server_parent_class)->dispose (object);
 }
@@ -253,6 +266,15 @@ grd_vnc_server_constructed (GObject *object)
 static void
 grd_vnc_server_init (GrdVncServer *vnc_server)
 {
+  GrdThrottlerLimits *limits;
+
+  limits = grd_throttler_limits_new ();
+  /* TODO: Add the rfbScreen instance to GrdVncServer to support multiple
+   * sessions. */
+  grd_throttler_limits_set_max_global_connections (limits, 1);
+  vnc_server->throttler = grd_throttler_new (limits,
+                                             allow_connection_cb,
+                                             vnc_server);
 }
 
 static void
-- 
2.53.0