[gtk/wip/otte/for-main: 3/4] x11: Explicitly track end of stream

[Benjamin Otte <otte src gnome org>]

commit 6fc5e04d7c868b9b4efdd957d03ae5d3bbd91b12
Author: Benjamin Otte <otte redhat com>
Date:   Mon Dec 13 01:52:30 2021 +0100

    x11: Explicitly track end of stream
    
    The OutputStream needs to write a 0 byte end of stream Property. We need
    to track if that has been written, and we do that with that new
    property.
    
    We also use that property to always request flushes when the stream is
    being closed, so that we don't wait for another flush() call.

 gdk/x11/gdkselectionoutputstream-x11.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/gdk/x11/gdkselectionoutputstream-x11.c b/gdk/x11/gdkselectionoutputstream-x11.c
index 7b45638dd3..7371f1c0f3 100644
--- a/gdk/x11/gdkselectionoutputstream-x11.c
+++ b/gdk/x11/gdkselectionoutputstream-x11.c
@@ -57,6 +57,7 @@ struct _GdkX11SelectionOutputStreamPrivate {
   GTask *pending_task;
 
   guint incr : 1;
+  guint sent_end_of_stream : 1;
   guint delete_pending : 1; /* owns a reference */
 };
 
@@ -176,12 +177,16 @@ gdk_x11_selection_output_stream_needs_flush_unlocked (GdkX11SelectionOutputStrea
 {
   GdkX11SelectionOutputStreamPrivate *priv = gdk_x11_selection_output_stream_get_instance_private (stream);
 
-  if (priv->data->len == 0 && priv->notify == NULL)
+  if (priv->sent_end_of_stream)
     return FALSE;
 
-  if (g_output_stream_is_closing (G_OUTPUT_STREAM (stream)))
+  if (g_output_stream_is_closing (G_OUTPUT_STREAM (stream)) ||
+      g_output_stream_is_closed (G_OUTPUT_STREAM (stream)))
     return TRUE;
 
+  if (priv->data->len == 0 && priv->notify == NULL)
+    return FALSE;
+
   if (priv->flush_requested)
     return TRUE;
 
@@ -284,6 +289,8 @@ gdk_x11_selection_output_stream_perform_flush (GdkX11SelectionOutputStream *stre
       g_byte_array_remove_range (priv->data, 0, n_elements * element_size);
       if (priv->data->len < element_size)
         priv->flush_requested = FALSE;
+      if (!priv->incr || n_elements == 0)
+        priv->sent_end_of_stream = TRUE;
     }
 
   if (priv->notify)