From 607846879eee368334fef8763ef53ccc587c10a6 Mon Sep 17 00:00:00 2001
From: Benjamin Otte <otte@redhat.com>
Date: Mon, 11 Apr 2011 02:32:26 +0200
Subject: [PATCH] cssprovider: Keep track of passed in error differently

Instead of having an error member in the CSS provider's private struct,
connect a signal handler when an error is passed in. This has two
advantages:
1) It makes the code clearer as we don't have to keep track of an error
   member anywhere.
2) It causes a non-emission of the g_warning() when an error was passed
   in, because it only triggers when no signal handlers are connected.
   So we get identical behavior to GTK 3.0 where warnings where only
   emitted when no error was passed in.
---
 gtk/gtkcssprovider.c | 56 ++++++++++++++++++++++++++++----------------
 1 file changed, 36 insertions(+), 20 deletions(-)

diff --git a/gtk/gtkcssprovider.c b/gtk/gtkcssprovider.c
index c121bed7ea..fda123b7ac 100644
--- a/gtk/gtkcssprovider.c
+++ b/gtk/gtkcssprovider.c
@@ -800,9 +800,6 @@ struct _GtkCssProviderPrivate
   GHashTable *symbolic_colors;
 
   GPtrArray *selectors_info;
-
-  /* Current parser state */
-  GError *error;
 };
 
 enum ParserScope {
@@ -869,14 +866,6 @@ gtk_css_provider_parsing_error (GtkCssProvider  *provider,
                                 guint            position,
                                 const GError *   error)
 {
-  GtkCssProviderPrivate *priv = provider->priv;
-
-  if (!priv->error)
-    {
-      priv->error = g_error_copy (error);
-      g_prefix_error (&priv->error, "%s:%u:%u: ", path ? path : "<unknown>", line, position);
-    }
-
   /* Only emit a warning when we have no error handlers. This is our
    * default handlers. And in this case erroneous CSS files are a bug
    * and should be fixed.
@@ -1774,10 +1763,6 @@ css_provider_reset_parser (GtkCssProvider *css_provider)
   priv = css_provider->priv;
 
   gtk_css_scanner_reset (priv->scanner);
-
-  if (priv->error)
-    g_error_free (priv->error);
-  priv->error = NULL;
 }
 
 static void
@@ -2599,18 +2584,37 @@ gtk_css_provider_reset (GtkCssProvider *css_provider)
     g_ptr_array_remove_range (priv->selectors_info, 0, priv->selectors_info->len);
 }
 
+static void
+gtk_css_provider_propagate_error (GtkCssProvider  *provider,
+                                  const gchar     *path,
+                                  guint            line,
+                                  guint            position,
+                                  const GError    *error,
+                                  GError         **propagate_to)
+{
+  /* we already set an error. And we'd like to keep the first one */
+  if (*propagate_to)
+    return;
+
+  *propagate_to = g_error_copy (error);
+  g_prefix_error (propagate_to, "%s:%u:%u: ", path ? path : "<unknown>", line, position);
+}
 
 static gboolean
 parse_stylesheet (GtkCssProvider  *css_provider,
                   GScanner        *scanner,
                   GError         **error)
 {
-  GtkCssProviderPrivate *priv;
-  gboolean result;
+  gulong error_handler;
 
-  result = TRUE;
+  if (error)
+    error_handler = g_signal_connect (css_provider,
+                                      "parsing-error",
+                                      G_CALLBACK (gtk_css_provider_propagate_error),
+                                      error);
+  else
+    error_handler = 0; /* silence gcc */
 
-  priv = css_provider->priv;
   g_scanner_get_next_token (scanner);
 
   while (!g_scanner_eof (scanner))
@@ -2634,7 +2638,19 @@ parse_stylesheet (GtkCssProvider  *css_provider,
       g_scanner_get_next_token (scanner);
     }
 
-  return result;
+  if (error)
+    {
+      g_signal_handler_disconnect (css_provider, error_handler);
+      
+      if (*error)
+        {
+          /* We clear all contents from the provider for backwards compat reasons */
+          gtk_css_provider_reset (css_provider);
+          return FALSE;
+        }
+    }
+
+  return TRUE;
 }
 
 /**