[gnome-disk-utility] Ensure sorted and predicted device order in multi-selection mode

[David Zeuthen <davidz src gnome org>]

commit a3c1c99940a949a8ddd68eea367bc95d6683faf8
Author: David Zeuthen <zeuthen gmail com>
Date:   Wed Dec 5 13:47:56 2012 -0500

    Ensure sorted and predicted device order in multi-selection mode
    
    Before this fix, the selected devices were retrieved in random order
    which made confirmation dialogs look bad (e.g. loop3, loop2, loop1,
    loop0) and, worse, also affected RAID layouts. With this change things
    are predictable.
    
    Signed-off-by: David Zeuthen <zeuthen gmail com>

 src/disks/gdudevicetreemodel.c |  107 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 107 insertions(+), 0 deletions(-)
---
diff --git a/src/disks/gdudevicetreemodel.c b/src/disks/gdudevicetreemodel.c
index 0d1b327..122351d 100644
--- a/src/disks/gdudevicetreemodel.c
+++ b/src/disks/gdudevicetreemodel.c
@@ -38,6 +38,8 @@ struct _GduDeviceTreeModel
 
   /* "Polling Every Few Seconds" ... e.g. power state */
   guint pefs_timeout_id;
+
+  GHashTable *sort_mz;
 };
 
 typedef struct
@@ -1595,6 +1597,103 @@ gdu_device_tree_model_toggle_selected (GduDeviceTreeModel *model,
 
 /* ---------------------------------------------------------------------------------------------------- */
 
+/* It's pretty expensive to compute the UDisksObjectInfo on _each_
+ * comparison when sorting ... so we use a simple memoization
+ * technique
+ */
+
+static void
+sort_begin (GduDeviceTreeModel *model)
+{
+  g_assert (model->sort_mz == NULL);
+  model->sort_mz = g_hash_table_new_full (g_direct_hash,
+                                          g_direct_equal,
+                                          g_object_unref,
+                                          g_object_unref);
+}
+
+static UDisksObjectInfo *
+sort_get_object_info (GduDeviceTreeModel *model,
+                      UDisksObject       *object)
+{
+  UDisksObjectInfo *ret;
+
+  g_assert (model->sort_mz != NULL);
+
+  ret = g_hash_table_lookup (model->sort_mz, object);
+  if (ret != NULL)
+    {
+      g_object_ref (ret);
+      goto out;
+    }
+
+  ret = udisks_client_get_object_info (model->client, object);
+  g_hash_table_insert (model->sort_mz, g_object_ref (object), g_object_ref (ret));
+
+ out:
+  return ret;
+}
+
+static void
+sort_end (GduDeviceTreeModel *model)
+{
+  g_assert (model->sort_mz != NULL);
+  g_hash_table_destroy (model->sort_mz);
+  model->sort_mz = NULL;
+}
+
+static gint
+sort_func (gconstpointer a,
+           gconstpointer b,
+           gpointer      user_data,
+           gboolean      is_block)
+{
+  GduDeviceTreeModel *model = GDU_DEVICE_TREE_MODEL (user_data);
+  UDisksObjectInfo *ia = NULL, *ib = NULL;
+  gint ret;
+
+  if (is_block)
+    {
+      UDisksObject *oa, *ob;
+      oa = (UDisksObject *) g_dbus_interface_get_object (G_DBUS_INTERFACE (UDISKS_BLOCK (a)));
+      ob = (UDisksObject *) g_dbus_interface_get_object (G_DBUS_INTERFACE (UDISKS_BLOCK (b)));
+      if (oa != NULL)
+        ia = sort_get_object_info (model, oa);
+      if (ob != NULL)
+        ib = sort_get_object_info (model, ob);
+    }
+  else
+    {
+      ia = sort_get_object_info (model, UDISKS_OBJECT (a));
+      ib = sort_get_object_info (model, UDISKS_OBJECT (b));
+    }
+
+  ret = g_strcmp0 (ia != NULL ? udisks_object_info_get_sort_key (ia) : NULL,
+                   ib != NULL ? udisks_object_info_get_sort_key (ib) : NULL);
+
+  g_clear_object (&ib);
+  g_clear_object (&ia);
+  return ret;
+}
+
+static gint
+sort_func_object (gconstpointer a,
+                  gconstpointer b,
+                  gpointer      user_data)
+{
+  return sort_func (a, b, user_data, FALSE);
+}
+
+static gint
+sort_func_block (gconstpointer a,
+                 gconstpointer b,
+                 gpointer      user_data)
+{
+  return sort_func (a, b, user_data, TRUE);
+}
+
+/* ---------------------------------------------------------------------------------------------------- */
+
 static gboolean
 get_selected_cb (GtkTreeModel  *model,
                  GtkTreePath   *path,
@@ -1632,6 +1731,10 @@ gdu_device_tree_model_get_selected (GduDeviceTreeModel *model)
 
   gtk_tree_model_foreach (GTK_TREE_MODEL (model), get_selected_cb, &ret);
 
+  sort_begin (model);
+  ret = g_list_sort_with_data (ret, sort_func_object, model);
+  sort_end (model);
+
   return ret;
 }
 
@@ -1674,6 +1777,10 @@ gdu_device_tree_model_get_selected_blocks (GduDeviceTreeModel *model)
 
   gtk_tree_model_foreach (GTK_TREE_MODEL (model), get_selected_blocks_cb, &ret);
 
+  sort_begin (model);
+  ret = g_list_sort_with_data (ret, sort_func_block, model);
+  sort_end (model);
+
   return ret;
 }