[gnome-builder] gca-service: don't use shared dbus session bus

[Christian Hergert <chergert src gnome org>]

commit 4517b61a5f1f7beade4c74a348c718a1db5a7d0b
Author: Christian Hergert <christian hergert me>
Date:   Mon Apr 27 15:26:54 2015 -0700

    gca-service: don't use shared dbus session bus
    
    In this case, we were using the shared dbus connection. This two can be
    closed out from under us and cause us to fail to save unsaved files.
    
    Instead, this uses a private dbus connection to the session bus for
    GCA related activity.
    
    Additionally, we handle the closed signal and release the connection and
    proxies, causing them to be reloaded on the next request.

 libide/gca/ide-gca-service.c |   95 ++++++++++++++++++++++++++++++++----------
 1 files changed, 73 insertions(+), 22 deletions(-)
---
diff --git a/libide/gca/ide-gca-service.c b/libide/gca/ide-gca-service.c
index e0c69d2..10b7b3a 100644
--- a/libide/gca/ide-gca-service.c
+++ b/libide/gca/ide-gca-service.c
@@ -22,18 +22,74 @@
 #include <glib/gi18n.h>
 
 #include "ide-gca-service.h"
+#include "ide-macros.h"
 
 struct _IdeGcaService
 {
-  IdeService  parent_instance;
+  IdeService       parent_instance;
 
-  GHashTable *proxy_cache;
-};
+  gulong           bus_closed_handler;
 
-static GDBusConnection *gDBus;
+  GDBusConnection *bus;
+  GHashTable      *proxy_cache;
+};
 
 G_DEFINE_TYPE (IdeGcaService, ide_gca_service, IDE_TYPE_SERVICE)
 
+static void
+on_bus_closed (GDBusConnection *bus,
+               gboolean         remote_peer_vanished,
+               GError          *error,
+               gpointer         user_data)
+{
+  IdeGcaService *self = user_data;
+
+  g_assert (G_IS_DBUS_CONNECTION (bus));
+  g_assert (IDE_IS_GCA_SERVICE (self));
+
+  if (self->bus_closed_handler != 0)
+    ide_clear_signal_handler (bus, &self->bus_closed_handler);
+
+  g_clear_object (&self->bus);
+  g_hash_table_remove_all (self->proxy_cache);
+}
+
+static GDBusConnection *
+ide_gca_service_get_bus (IdeGcaService  *self,
+                         GCancellable   *cancellable,
+                         GError        **error)
+{
+  g_assert (IDE_IS_GCA_SERVICE (self));
+  g_assert (!cancellable || G_IS_CANCELLABLE (cancellable));
+
+  if (self->bus == NULL)
+    {
+      const GDBusConnectionFlags flags = (G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_CLIENT |
+                                          G_DBUS_CONNECTION_FLAGS_MESSAGE_BUS_CONNECTION);
+      g_autofree gchar *address = NULL;
+      g_autoptr(GDBusConnection) bus = NULL;
+
+      address = g_dbus_address_get_for_bus_sync (G_BUS_TYPE_SESSION, cancellable, error);
+      if (address == NULL)
+        return NULL;
+
+      bus = g_dbus_connection_new_for_address_sync (address, flags, NULL, cancellable, error);
+      if (bus == NULL)
+        return NULL;
+
+      self->bus_closed_handler = g_signal_connect (bus,
+                                                   "closed",
+                                                   G_CALLBACK (on_bus_closed),
+                                                   self);
+
+      g_dbus_connection_set_exit_on_close (bus, FALSE);
+
+      self->bus = g_object_ref (bus);
+    }
+
+  return self->bus;
+}
+
 static const gchar *
 remap_language (const gchar *lang_id)
 {
@@ -92,6 +148,8 @@ ide_gca_service_get_proxy_async (IdeGcaService       *self,
   g_autofree gchar *name = NULL;
   g_autofree gchar *object_path = NULL;
   GcaService *proxy;
+  GDBusConnection *bus;
+  GError *error = NULL;
 
   g_return_if_fail (IDE_IS_GCA_SERVICE (self));
   g_return_if_fail (language_id);
@@ -110,12 +168,11 @@ ide_gca_service_get_proxy_async (IdeGcaService       *self,
       return;
     }
 
-  if (!gDBus)
+  bus = ide_gca_service_get_bus (self, cancellable, &error);
+
+  if (bus == NULL)
     {
-      g_task_return_new_error (task,
-                               G_IO_ERROR,
-                               G_IO_ERROR_NOT_CONNECTED,
-                               _("Not connected to D-Bus."));
+      g_task_return_error (task, error);
       return;
     }
 
@@ -130,7 +187,7 @@ ide_gca_service_get_proxy_async (IdeGcaService       *self,
   name = g_strdup_printf ("org.gnome.CodeAssist.v1.%s", language_id);
   object_path = g_strdup_printf ("/org/gnome/CodeAssist/v1/%s", language_id);
 
-  gca_service_proxy_new (gDBus,
+  gca_service_proxy_new (bus,
                          G_DBUS_PROXY_FLAGS_NONE,
                          name,
                          object_path,
@@ -164,6 +221,12 @@ ide_gca_service_finalize (GObject *object)
 {
   IdeGcaService *self = (IdeGcaService *)object;
 
+  if (self->bus != NULL)
+    {
+      ide_clear_signal_handler (self->bus, &self->bus_closed_handler);
+      g_clear_object (&self->bus);
+    }
+
   g_clear_pointer (&self->proxy_cache, g_hash_table_unref);
 
   G_OBJECT_CLASS (ide_gca_service_parent_class)->finalize (object);
@@ -173,20 +236,8 @@ static void
 ide_gca_service_class_init (IdeGcaServiceClass *klass)
 {
   GObjectClass *object_class = G_OBJECT_CLASS (klass);
-  GError *error = NULL;
 
   object_class->finalize = ide_gca_service_finalize;
-
-  gDBus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, &error);
-
-  if (!gDBus)
-    {
-      g_warning (_("Failed to load D-Bus connection to session bus. "
-                   "Code assistance will be disabled. "
-                   "Error was: %s"),
-                 error->message);
-      g_clear_error (&error);
-    }
 }
 
 static void