gstreamer-sharp: Fix App{Src,Sink} constructors

Apparently GtkSharp expects each object has only one ToggleRef at any
time. Assigning element.Handle into Raw has a consequence that second
ToggleRef attempts to get created but fails on g_object_unref () that
breaks a GObject assertion:

  toggle_refs_notify: assertion failed: (tstack.n_toggle_refs == 1)

This is because toggle references should be removed with
g_object_remove_toggle_ref(), not a simple unref().

In order to avoid duplicate toggle references, introduce
ElementFactory.MakeRaw(), which creates a GstElement without its
accompanying C# object. The returned raw pointer can be assigned into
another GLib.Object without trouble.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1885>
This commit is contained in:
Jakub Adam 2020-07-06 23:15:22 +02:00 committed by GStreamer Marge Bot
parent 95ff949eff
commit 38a3af96d0
4 changed files with 46 additions and 6 deletions

View file

@ -27,9 +27,8 @@ namespace Gst.App {
partial class AppSink
{
public AppSink (String name) {
var element = ElementFactory.Make ("appsink", name);
Raw = element.Handle;
public AppSink (String name) : base(IntPtr.Zero) {
Raw = ElementFactory.MakeRaw("appsink", name);
}
}
}

View file

@ -27,9 +27,8 @@ namespace Gst.App {
partial class AppSrc
{
public AppSrc (String name) {
var element = ElementFactory.Make ("appsrc", name);
Raw = element.Handle;
public AppSrc (String name) : base(IntPtr.Zero) {
Raw = ElementFactory.MakeRaw ("appsrc", name);
}
}
}

View file

@ -0,0 +1,41 @@
//
// ElementFactory.cs
//
// Authors:
// Jakub Adam <jakub.adam@collabora.com>
//
// Copyright (C) 2020 Collabora Ltd.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
// 02110-1301 USA
namespace Gst
{
using System;
using System.Runtime.InteropServices;
public partial class ElementFactory
{
public static IntPtr MakeRaw(string factoryname, string name)
{
IntPtr native_factoryname = GLib.Marshaller.StringToPtrGStrdup(factoryname);
IntPtr native_name = GLib.Marshaller.StringToPtrGStrdup(name);
IntPtr raw_ret = gst_element_factory_make(native_factoryname, native_name);
GLib.Marshaller.Free(native_factoryname);
GLib.Marshaller.Free(native_name);
return raw_ret;
}
}
}

View file

@ -16,6 +16,7 @@ sources = [
'custom/DeviceProvider.cs',
'custom/DynamicSignal.cs',
'custom/Element.cs',
'custom/ElementFactory.cs',
'custom/FFTF32.cs',
'custom/Iterator.cs',
'custom/MapInfo.cs',