From 8c7025e72320775f915cdd776e09c7cbecd648ac Mon Sep 17 00:00:00 2001
From: Dan Winship <danw@gnome.org>
Date: Sun, 22 Apr 2012 15:20:14 -0400
Subject: [PATCH] gio: fix error handling in async case of
 GProxyAddressEnumerator

In the async case, a failed DNS lookup was causing the proxy
resolution to bail out immediately, rather than just moving on to the
next potential proxy (which might not need us to do the DNS lookup
beforehand). Fix that.
---
 gio/gproxyaddressenumerator.c | 123 ++++++++++++++++++++--------------
 1 file changed, 72 insertions(+), 51 deletions(-)

diff --git a/gio/gproxyaddressenumerator.c b/gio/gproxyaddressenumerator.c
index b7bc04d45..e4167db63 100644
--- a/gio/gproxyaddressenumerator.c
+++ b/gio/gproxyaddressenumerator.c
@@ -69,6 +69,7 @@ struct _GProxyAddressEnumeratorPrivate
   gchar			   *proxy_password;
   gboolean                  supports_hostname;
   GList			   *next_dest_ip;
+  GError                   *last_error;
 
   /* Async attributes */
   GSimpleAsyncResult *simple;
@@ -316,6 +317,13 @@ complete_async (GProxyAddressEnumeratorPrivate *priv)
     }
 
   priv->simple = NULL;
+
+  if (priv->last_error)
+    {
+      g_simple_async_result_take_error (simple, priv->last_error);
+      priv->last_error = NULL;
+    }
+
   g_simple_async_result_complete (simple);
   g_object_unref (simple);
 }
@@ -380,57 +388,14 @@ save_result (GProxyAddressEnumeratorPrivate *priv)
 					     g_object_unref);
 }
 
-static void
-dest_hostname_lookup_cb (GObject           *object,
-			 GAsyncResult      *result,
-			 gpointer           user_data)
-{
-  GError *error = NULL;
-  GProxyAddressEnumeratorPrivate *priv = user_data;
-  GSimpleAsyncResult *simple = priv->simple;
-
-  priv->dest_ips = g_resolver_lookup_by_name_finish (G_RESOLVER (object),
-						     result,
-						     &error);
-  if (priv->dest_ips)
-    save_result (priv);
-  else
-    g_simple_async_result_take_error (simple, error);
-
-  complete_async (priv); 
-}
+static void address_enumerate_cb (GObject      *object,
+				  GAsyncResult *result,
+				  gpointer	user_data);
 
 static void
-address_enumerate_cb (GObject	   *object,
-		      GAsyncResult *result,
-		      gpointer	    user_data)
+next_proxy (GProxyAddressEnumeratorPrivate *priv)
 {
-  GError *error = NULL;
-  GProxyAddressEnumeratorPrivate *priv = user_data;
-  GSimpleAsyncResult *simple = priv->simple;
-
-  priv->proxy_address =
-    g_socket_address_enumerator_next_finish (priv->addr_enum,
-					     result,
-					     &error);
-  if (priv->proxy_address)
-    {
-      if (!priv->supports_hostname && !priv->dest_ips)
-	{
-	  GResolver *resolver;
-	  resolver = g_resolver_get_default();
-	  g_resolver_lookup_by_name_async (resolver,
-					   priv->dest_hostname,
-					   priv->cancellable,
-					   dest_hostname_lookup_cb,
-					   priv);
-	  g_object_unref (resolver);
-	  return;
-	}
-
-      save_result (priv);
-    }
-  else if (*priv->next_proxy)
+  if (*priv->next_proxy)
     {
       g_object_unref (priv->addr_enum);
       priv->addr_enum = NULL;
@@ -453,10 +418,64 @@ address_enumerate_cb (GObject	   *object,
 	}
     }
 
-  if (error)
-    g_simple_async_result_take_error (simple, error);
+  complete_async (priv);
+}
 
-  complete_async (priv); 
+static void
+dest_hostname_lookup_cb (GObject           *object,
+			 GAsyncResult      *result,
+			 gpointer           user_data)
+{
+  GProxyAddressEnumeratorPrivate *priv = user_data;
+
+  g_clear_error (&priv->last_error);
+  priv->dest_ips = g_resolver_lookup_by_name_finish (G_RESOLVER (object),
+						     result,
+						     &priv->last_error);
+  if (priv->dest_ips)
+    {
+      save_result (priv);
+      complete_async (priv);
+    }
+  else
+    {
+      g_clear_object (&priv->proxy_address);
+      next_proxy (priv);
+    }
+}
+
+static void
+address_enumerate_cb (GObject	   *object,
+		      GAsyncResult *result,
+		      gpointer	    user_data)
+{
+  GProxyAddressEnumeratorPrivate *priv = user_data;
+
+  g_clear_error (&priv->last_error);
+  priv->proxy_address =
+    g_socket_address_enumerator_next_finish (priv->addr_enum,
+					     result,
+					     &priv->last_error);
+  if (priv->proxy_address)
+    {
+      if (!priv->supports_hostname && !priv->dest_ips)
+	{
+	  GResolver *resolver;
+	  resolver = g_resolver_get_default();
+	  g_resolver_lookup_by_name_async (resolver,
+					   priv->dest_hostname,
+					   priv->cancellable,
+					   dest_hostname_lookup_cb,
+					   priv);
+	  g_object_unref (resolver);
+	  return;
+	}
+
+      save_result (priv);
+      complete_async (priv);
+    }
+  else
+    next_proxy (priv);
 }
 
 static void
@@ -672,6 +691,8 @@ g_proxy_address_enumerator_finalize (GObject *object)
   if (priv->cancellable)
     g_object_unref (priv->cancellable);
 
+  g_clear_error (&priv->last_error);
+
   G_OBJECT_CLASS (g_proxy_address_enumerator_parent_class)->finalize (object);
 }