webrtc: Add properties to change the socket buffer sizes to ice object

libnice doesn't touch the kernel buffer sizes. When dealing with RTP data,
it's generally advisable to increase them to avoid dropping packets locally.
This is especially important when running multiple higher bitrate streams at
the same time.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1366>

ext/webrtc/icestream.c

@@ -192,6 +192,12 @@ gst_webrtc_ice_stream_gather_candidates (GstWebRTCICEStream * stream)
     return FALSE;
   }
 
+  for (l = stream->priv->transports; l; l = l->next) {
+    GstWebRTCNiceTransport *trans = l->data;
+
+    gst_webrtc_nice_transport_update_buffer_size (trans);
+  }
+
   g_object_unref (agent);
   return TRUE;
 }

ext/webrtc/nicetransport.c

@@ -24,6 +24,8 @@
 #include "nicetransport.h"
 #include "icestream.h"
 
+#include <gio/gnetworking.h>
+
 #define GST_CAT_DEFAULT gst_webrtc_nice_transport_debug
 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
 
@@ -37,6 +39,8 @@ enum
 {
   PROP_0,
   PROP_STREAM,
+  PROP_SEND_BUFFER_SIZE,
+  PROP_RECEIVE_BUFFER_SIZE
 };
 
 //static guint gst_webrtc_nice_transport_signals[LAST_SIGNAL] = { 0 };
@@ -44,6 +48,9 @@ enum
 struct _GstWebRTCNiceTransportPrivate
 {
   gboolean running;
+
+  gint send_buffer_size;
+  gint receive_buffer_size;
 };
 
 #define gst_webrtc_nice_transport_parent_class parent_class
@@ -115,6 +122,14 @@ gst_webrtc_nice_transport_set_property (GObject * object, guint prop_id,
         gst_object_unref (nice->stream);
       nice->stream = g_value_dup_object (value);
       break;
+    case PROP_SEND_BUFFER_SIZE:
+      nice->priv->send_buffer_size = g_value_get_int (value);
+      gst_webrtc_nice_transport_update_buffer_size (nice);
+      break;
+    case PROP_RECEIVE_BUFFER_SIZE:
+      nice->priv->receive_buffer_size = g_value_get_int (value);
+      gst_webrtc_nice_transport_update_buffer_size (nice);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -131,6 +146,12 @@ gst_webrtc_nice_transport_get_property (GObject * object, guint prop_id,
     case PROP_STREAM:
       g_value_set_object (value, nice->stream);
       break;
+    case PROP_SEND_BUFFER_SIZE:
+      g_value_set_int (value, nice->priv->send_buffer_size);
+      break;
+    case PROP_RECEIVE_BUFFER_SIZE:
+      g_value_set_int (value, nice->priv->receive_buffer_size);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -147,6 +168,51 @@ gst_webrtc_nice_transport_finalize (GObject * object)
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
+void
+gst_webrtc_nice_transport_update_buffer_size (GstWebRTCNiceTransport * nice)
+{
+  GstWebRTCICETransport *ice = GST_WEBRTC_ICE_TRANSPORT (nice);
+  NiceAgent *agent = NULL;
+  GPtrArray *sockets;
+  guint i;
+
+  g_object_get (nice->stream->ice, "agent", &agent, NULL);
+  g_assert (agent != NULL);
+
+  sockets = nice_agent_get_sockets (agent, nice->stream->stream_id,
+      ice->component + 1);
+  if (sockets == NULL) {
+    g_object_unref (agent);
+    return;
+  }
+
+  for (i = 0; i < sockets->len; i++) {
+    GSocket *gsocket = g_ptr_array_index (sockets, i);
+#ifdef SO_SNDBUF
+    if (nice->priv->send_buffer_size != 0) {
+      GError *gerror = NULL;
+      if (!g_socket_set_option (gsocket, SOL_SOCKET, SO_SNDBUF,
+              nice->priv->send_buffer_size, &gerror))
+        GST_WARNING_OBJECT (nice, "Could not set send buffer size : %s",
+            gerror->message);
+      g_clear_error (&gerror);
+    }
+#endif
+#ifdef SO_RCVBUF
+    if (nice->priv->receive_buffer_size != 0) {
+      GError *gerror = NULL;
+      if (!g_socket_set_option (gsocket, SOL_SOCKET, SO_RCVBUF,
+              nice->priv->receive_buffer_size, &gerror))
+        GST_WARNING_OBJECT (nice, "Could not set send receive size : %s",
+            gerror->message);
+      g_clear_error (&gerror);
+    }
+#endif
+  }
+  g_ptr_array_unref (sockets);
+}
+
+
 static void
 _on_new_selected_pair (NiceAgent * agent, guint stream_id,
     NiceComponentType component, NiceCandidate * lcandidate,
@@ -245,6 +311,34 @@ gst_webrtc_nice_transport_class_init (GstWebRTCNiceTransportClass * klass)
           "WebRTC ICE Stream", "ICE stream associated with this transport",
           GST_TYPE_WEBRTC_ICE_STREAM,
           G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
+
+  /**
+   * GstWebRTCNiceTransport:send-buffer-size:
+   *
+   * Size of the kernel send buffer in bytes, 0=default
+   *
+   * Since: 1.20
+   */
+
+  g_object_class_install_property (G_OBJECT_CLASS (klass),
+      PROP_SEND_BUFFER_SIZE, g_param_spec_int ("send-buffer-size",
+          "Send Buffer Size",
+          "Size of the kernel send buffer in bytes, 0=default", 0, G_MAXINT, 0,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  /**
+   * GstWebRTCNiceTransport:receive-buffer-size:
+   *
+   * Size of the kernel receive buffer in bytes, 0=default
+   *
+   * Since: 1.20
+   */
+
+  g_object_class_install_property (G_OBJECT_CLASS (klass),
+      PROP_RECEIVE_BUFFER_SIZE, g_param_spec_int ("receive-buffer-size",
+          "Receive Buffer Size",
+          "Size of the kernel receive buffer in bytes, 0=default", 0, G_MAXINT,
+          0, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 }
 
 static void

ext/webrtc/nicetransport.h

@@ -50,8 +50,11 @@ struct _GstWebRTCNiceTransportClass
   GstWebRTCICETransportClass               parent_class;
 };
 
-GstWebRTCNiceTransport *    gst_webrtc_nice_transport_new               (GstWebRTCICEStream * stream,
-                                                                         GstWebRTCICEComponent component);
+GstWebRTCNiceTransport * gst_webrtc_nice_transport_new                (GstWebRTCICEStream * stream,
+                                                                       GstWebRTCICEComponent component);
+
+void                     gst_webrtc_nice_transport_update_buffer_size (GstWebRTCNiceTransport * nice);
+
 
 G_END_DECLS