[gtk/async-highlight] Fix a lockup problem

[Matthias Clasen <matthiasc src gnome org>]

commit e323ca3273e28de5dc4ce010b20fd09de6a6e8d1
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Aug 13 11:49:41 2020 -0400

    Fix a lockup problem

 demos/gtk-demo/main.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)
---
diff --git a/demos/gtk-demo/main.c b/demos/gtk-demo/main.c
index 49502e1ab2..89222e179b 100644
--- a/demos/gtk-demo/main.c
+++ b/demos/gtk-demo/main.c
@@ -8,6 +8,9 @@
 #include <gtk/gtk.h>
 #include <glib/gstdio.h>
 
+#include <gio/gunixoutputstream.h>
+#include <fcntl.h>
+
 #include "demos.h"
 
 static GtkWidget *info_view;
@@ -363,6 +366,14 @@ fontify (const char    *format,
       return;
     }
 
+  /* Work around https://gitlab.gnome.org/GNOME/glib/-/issues/2182 */
+  if (G_IS_UNIX_OUTPUT_STREAM (g_subprocess_get_stdin_pipe (subprocess)))
+    {
+      GOutputStream *stdin_pipe = g_subprocess_get_stdin_pipe (subprocess);
+      int fd = g_unix_output_stream_get_fd (G_UNIX_OUTPUT_STREAM (stdin_pipe));
+      fcntl (fd, F_SETFL, O_NONBLOCK);
+    }
+
   g_subprocess_communicate_async (subprocess,
                                   stdin_buf,
                                   NULL,
@@ -761,7 +772,7 @@ load_file (const char *demoname,
   text = gtk_text_buffer_get_text (source_buffer, &start, &end, TRUE);
   bytes = g_bytes_new_static (text, strlen (text));
 
-  fontify ("c", source_buffer, bytes);
+  //fontify ("c", source_buffer, bytes);
 
   g_bytes_unref (bytes);