daemon: avoid using floating GVariant refs

It makes it harder to keep track of ownership except in the trivial
`_new ()` case for which they were designed (i.e. shoving straight into
another glib GVariant function that takes ownership of it right away).

Closes: #1160
Approved by: cgwalters

src/daemon/rpmostree-package-variants.c

@@ -28,11 +28,11 @@
  * package_to_variant
  * @package: RpmOstreePackage
  *
- * Returns: A GVariant of (sss) where values are
+ * Returns: A floating GVariant of (sss) where values are
  * (package name, evr, arch)
  */
 static GVariant *
-package_to_variant (RpmOstreePackage *package)
+package_variant_new (RpmOstreePackage *package)
 {
   return g_variant_new ("(sss)",
                         rpm_ostree_package_get_name (package),
@@ -54,20 +54,20 @@ build_diff_variant (const gchar *name,
   if (old_package)
     {
       g_variant_builder_add (&options_builder, "{sv}", "PreviousPackage",
-                             package_to_variant (old_package));
+                             package_variant_new (old_package));
     }
 
   if (new_package)
     {
       g_variant_builder_add (&options_builder, "{sv}", "NewPackage",
-                             package_to_variant (new_package));
+                             package_variant_new (new_package));
     }
 
   g_variant_builder_init (&builder, G_VARIANT_TYPE_TUPLE);
   g_variant_builder_add (&builder, "s", name);
   g_variant_builder_add (&builder, "u", type);
   g_variant_builder_add_value (&builder, g_variant_builder_end (&options_builder));
-  return g_variant_builder_end (&builder);
+  return g_variant_ref_sink (g_variant_builder_end (&builder));
 }
 
 
@@ -117,8 +117,8 @@ rpm_ostree_db_diff_variant_compare_by_type (const void *v1,
  * @repo: A OstreeRepo
  * @old_ref: old ref to use
  * @new_ref: New ref to use
- * @out_variant: floating GVariant that represents the differences
- *   between the rpm databases on the given refs.
+ * @out_variant: GVariant that represents the differences between the rpm
+ *   databases on the given refs.
  * GCancellable: *cancellable
  * GError: **error
  *
@@ -144,7 +144,8 @@ rpm_ostree_db_diff_variant (OstreeRepo *repo,
 
   g_assert_cmpuint (modified_old->len, ==, modified_new->len);
 
-  g_autoptr(GPtrArray) found = g_ptr_array_new ();
+  g_autoptr(GPtrArray) found =
+    g_ptr_array_new_with_free_func ((GDestroyNotify) g_variant_unref);
 
   for (guint i = 0; i < modified_old->len; i++)
     {
@@ -182,12 +183,10 @@ rpm_ostree_db_diff_variant (OstreeRepo *repo,
   for (guint i = 0; i < found->len; i++)
     g_variant_builder_add_value (&builder, found->pdata[i]);
 
-  GVariant *variant = NULL;
   if (found->len > 0)
-    variant = g_variant_builder_end (&builder);
+    *out_variant = g_variant_builder_end (&builder);
   else
-    variant = g_variant_new ("a(sua{sv})", NULL);
-
-  *out_variant = g_steal_pointer (&variant);
+    *out_variant = g_variant_new ("a(sua{sv})", NULL);
+  g_variant_ref_sink (*out_variant);
   return TRUE;
 }

src/daemon/rpmostreed-deployment-utils.c

@@ -435,5 +435,5 @@ rpmostreed_commit_generate_cached_details_variant (OstreeDeployment *deployment,
                                           NULL, NULL, &dict, error))
     return NULL;
 
-  return g_variant_dict_end (&dict);
+  return g_variant_ref_sink (g_variant_dict_end (&dict));
 }

src/daemon/rpmostreed-os.c

@@ -314,7 +314,7 @@ os_handle_get_deployments_rpm_diff (RPMOSTreeOS *interface,
   glnx_unref_object OstreeDeployment *deployment1 = NULL;
   OstreeSysroot *ot_sysroot = NULL;
   OstreeRepo *ot_repo = NULL;
-  GVariant *value = NULL; /* freed when invoked */
+  g_autoptr(GVariant) value = NULL;
   GError *local_error = NULL;
   const gchar *ref0;
   const gchar *ref1;
@@ -376,8 +376,8 @@ os_handle_get_cached_update_rpm_diff (RPMOSTreeOS *interface,
   OstreeRepo *ot_repo = NULL;
   glnx_unref_object OstreeDeployment *base_deployment = NULL;
   GCancellable *cancellable = NULL;
-  GVariant *value = NULL; /* freed when invoked */
-  GVariant *details = NULL; /* freed when invoked */
+  g_autoptr(GVariant) value = NULL;
+  g_autoptr(GVariant) details = NULL;
   GError *local_error = NULL;
 
   global_sysroot = rpmostreed_sysroot_get ();
@@ -1369,8 +1369,8 @@ os_handle_get_cached_rebase_rpm_diff (RPMOSTreeOS *interface,
   g_autoptr(RpmOstreeOrigin) origin = NULL;
   g_autofree gchar *comp_ref = NULL;
   GError *local_error = NULL;
-  GVariant *value = NULL; /* freed when invoked */
-  GVariant *details = NULL; /* freed when invoked */
+  g_autoptr(GVariant) value = NULL;
+  g_autoptr(GVariant) details = NULL;
 
   /* TODO: Totally ignoring packages for now */
 
@@ -1492,8 +1492,8 @@ os_handle_get_cached_deploy_rpm_diff (RPMOSTreeOS *interface,
   g_autofree char *checksum = NULL;
   g_autofree char *version = NULL;
   g_autoptr(GCancellable) cancellable = NULL;
-  GVariant *value = NULL;
-  GVariant *details = NULL;
+  g_autoptr(GVariant) value = NULL;
+  g_autoptr(GVariant) details = NULL;
   GError *local_error = NULL;
   GError **error = &local_error;
 
@@ -1629,7 +1629,7 @@ rpmostreed_os_load_internals (RpmostreedOS *self, GError **error)
   GVariant *booted_variant = NULL;
   GVariant *default_variant = NULL;
   GVariant *rollback_variant = NULL;
-  GVariant *cached_update = NULL;
+  g_autoptr(GVariant) cached_update = NULL;
   gboolean has_cached_updates = FALSE;
 
   name = rpmostree_os_get_name (RPMOSTREE_OS (self));