From 1523382b18e79f4576700b01ecc70d727bd944d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
Date: Sat, 26 Dec 2020 11:42:45 +0200
Subject: [PATCH] player: PlayerVideoRenderer::create_sink_element() is
 transfer none

---
 gstreamer-player/Cargo.toml                   |  1 +
 .../src/subclass/player_video_renderer.rs     | 31 +++++++++++++++++--
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/gstreamer-player/Cargo.toml b/gstreamer-player/Cargo.toml
index b920b902b..302df4b02 100644
--- a/gstreamer-player/Cargo.toml
+++ b/gstreamer-player/Cargo.toml
@@ -20,6 +20,7 @@ ffi = { package = "gstreamer-player-sys", path = "sys" }
 glib = { git = "https://github.com/gtk-rs/gtk-rs" }
 gst = { package = "gstreamer", path = "../gstreamer", features = ["v1_12"] }
 gst-video = { package = "gstreamer-video", path = "../gstreamer-video", features = ["v1_12"] }
+once_cell = "1.0"
 
 [build-dependencies]
 gstreamer-rs-lgpl-docs = { path = "../docs", optional = true }
diff --git a/gstreamer-player/src/subclass/player_video_renderer.rs b/gstreamer-player/src/subclass/player_video_renderer.rs
index af4217cd8..45c12074c 100644
--- a/gstreamer-player/src/subclass/player_video_renderer.rs
+++ b/gstreamer-player/src/subclass/player_video_renderer.rs
@@ -25,12 +25,37 @@ unsafe extern "C" fn video_renderer_create_video_sink<T: PlayerVideoRendererImpl
     video_renderer: *mut ffi::GstPlayerVideoRenderer,
     player: *mut ffi::GstPlayer,
 ) -> *mut gst::ffi::GstElement {
+    use once_cell::sync::Lazy;
+    static VIDEO_SINK_QUARK: Lazy<glib::Quark> =
+        Lazy::new(|| glib::Quark::from_string("gstreamer-rs-player-video-sink"));
+
     let instance = &*(video_renderer as *mut T::Instance);
     let imp = instance.get_impl();
 
-    imp.create_video_sink(
+    let sink = imp.create_video_sink(
         from_glib_borrow::<_, PlayerVideoRenderer>(video_renderer).unsafe_cast_ref(),
         &Player::from_glib_borrow(player),
-    )
-    .to_glib_full()
+    );
+
+    let sink_ptr: *mut gst::ffi::GstElement = sink.to_glib_none().0;
+
+    let old_sink_ptr =
+        glib::gobject_ffi::g_object_get_qdata(video_renderer as *mut _, VIDEO_SINK_QUARK.to_glib())
+            as *mut gst::ffi::GstElement;
+    if !old_sink_ptr.is_null() && old_sink_ptr != sink_ptr {
+        panic!("Video sink must not change");
+    }
+
+    unsafe extern "C" fn unref(ptr: glib::ffi::gpointer) {
+        glib::gobject_ffi::g_object_unref(ptr as *mut _);
+    }
+
+    glib::gobject_ffi::g_object_set_qdata_full(
+        video_renderer as *mut _,
+        VIDEO_SINK_QUARK.to_glib(),
+        glib::gobject_ffi::g_object_ref(sink_ptr as *mut _) as *mut _,
+        Some(unref),
+    );
+
+    sink_ptr
 }