rtmp2/connection: Separate inner from outer cancelling

The connection cancels itself when it is closed. To avoid the
cancellable passed to `gst_rtmp_connection_new` from being unexpectedly
cancelled, separate inner from outer cancellation by holding two
cancellables.

Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/issues/1558

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/2111>

diff --git a/gst/rtmp2/rtmp/rtmpconnection.c b/gst/rtmp2/rtmp/rtmpconnection.c
index a6eb5ad..d9af4d2 100644 (file)
--- a/gst/rtmp2/rtmp/rtmpconnection.c
+++ b/gst/rtmp2/rtmp/rtmpconnection.c
@@ -55,6 +55,9 @@ struct _GstRtmpConnection
   GAsyncQueue *output_queue;
   GMainContext *main_context;
 
+  GCancellable *outer_cancellable;
+  gulong cancel_handler_id;
+
   GSource *input_source;
   GByteArray *input_bytes;
   guint input_needed_bytes;
@@ -101,6 +104,8 @@ typedef struct
 
 static void gst_rtmp_connection_dispose (GObject * object);
 static void gst_rtmp_connection_finalize (GObject * object);
+static void gst_rtmp_connection_set_cancellable (GstRtmpConnection * self,
+    GCancellable * cancellable);
 static void gst_rtmp_connection_emit_error (GstRtmpConnection * self);
 static gboolean gst_rtmp_connection_input_ready (GInputStream * is,
     gpointer user_data);
@@ -251,6 +256,7 @@ gst_rtmp_connection_class_init (GstRtmpConnectionClass * klass)
 static void
 gst_rtmp_connection_init (GstRtmpConnection * rtmpconnection)
 {
+  rtmpconnection->cancellable = g_cancellable_new ();
   rtmpconnection->output_queue =
       g_async_queue_new_full ((GDestroyNotify) gst_buffer_unref);
   rtmpconnection->input_streams = gst_rtmp_chunk_streams_new ();
@@ -277,6 +283,7 @@ gst_rtmp_connection_dispose (GObject * object)
   g_cancellable_cancel (rtmpconnection->cancellable);
   gst_rtmp_connection_set_input_handler (rtmpconnection, NULL, NULL, NULL);
   gst_rtmp_connection_set_output_handler (rtmpconnection, NULL, NULL, NULL);
+  gst_rtmp_connection_set_cancellable (rtmpconnection, NULL);
 
   G_OBJECT_CLASS (gst_rtmp_connection_parent_class)->dispose (object);
 }
@@ -332,6 +339,24 @@ gst_rtmp_connection_set_socket_connection (GstRtmpConnection * sc,
   g_source_attach (sc->input_source, sc->main_context);
 }
 
+static void
+gst_rtmp_connection_set_cancellable (GstRtmpConnection * self,
+    GCancellable * cancellable)
+{
+  g_cancellable_disconnect (self->outer_cancellable, self->cancel_handler_id);
+  g_clear_object (&self->outer_cancellable);
+  self->cancel_handler_id = 0;
+
+  if (cancellable == NULL)
+    return;
+
+  self->outer_cancellable = g_object_ref (cancellable);
+  self->cancel_handler_id =
+      g_cancellable_connect (cancellable, G_CALLBACK (g_cancellable_cancel),
+      g_object_ref (self->cancellable), g_object_unref);
+}
+
+
 GstRtmpConnection *
 gst_rtmp_connection_new (GSocketConnection * connection,
     GCancellable * cancellable)
@@ -339,12 +364,9 @@ gst_rtmp_connection_new (GSocketConnection * connection,
   GstRtmpConnection *sc;
 
   sc = g_object_new (GST_TYPE_RTMP_CONNECTION, NULL);
-  if (cancellable)
-    sc->cancellable = g_object_ref (cancellable);
-  else
-    sc->cancellable = g_cancellable_new ();
 
   gst_rtmp_connection_set_socket_connection (sc, connection);
+  gst_rtmp_connection_set_cancellable (sc, cancellable);
 
   return sc;
 }