[gnome-software] plugins: Add a custom cache object to datadir-apps to speed up each refine by 2500ms per run

[Richard Hughes <rhughes src gnome org>]

commit fb99634c317ba151dc12a30365356ee6e8c0c4aa
Author: Richard Hughes <richard hughsie com>
Date:   Thu Mar 7 12:10:37 2013 +0000

    plugins: Add a custom cache object to datadir-apps to speed up each refine by 2500ms per run
    
    The intital fillup still takes 2600ms, but repeat accesses are now blindingly quick at 3ms.

 src/plugins/gs-plugin-datadir-apps.c |   98 ++++++++++++++++++++++++----------
 1 files changed, 69 insertions(+), 29 deletions(-)
---
diff --git a/src/plugins/gs-plugin-datadir-apps.c b/src/plugins/gs-plugin-datadir-apps.c
index 2af6c85..52892d5 100644
--- a/src/plugins/gs-plugin-datadir-apps.c
+++ b/src/plugins/gs-plugin-datadir-apps.c
@@ -27,6 +27,13 @@ struct GsPluginPrivate {
        GHashTable              *cache;
 };
 
+typedef struct {
+       gchar           *id;
+       gchar           *name;
+       gchar           *summary;
+       GdkPixbuf       *pixbuf;
+} GsPluginDataDirAppsCacheItem;
+
 /**
  * gs_plugin_get_name:
  */
@@ -37,6 +44,20 @@ gs_plugin_get_name (void)
 }
 
 /**
+ * gs_plugin_datadir_apps_cache_item_free:
+ */
+static void
+gs_plugin_datadir_apps_cache_item_free (GsPluginDataDirAppsCacheItem *cache_item)
+{
+       g_free (cache_item->id);
+       g_free (cache_item->name);
+       g_free (cache_item->summary);
+       if (cache_item->pixbuf != NULL)
+               g_object_unref (cache_item->pixbuf);
+       g_slice_free (GsPluginDataDirAppsCacheItem, cache_item);
+}
+
+/**
  * gs_plugin_initialize:
  */
 void
@@ -47,7 +68,7 @@ gs_plugin_initialize (GsPlugin *plugin)
        plugin->priv->cache = g_hash_table_new_full (g_str_hash,
                                                     g_str_equal,
                                                     g_free,
-                                                    (GDestroyNotify) g_key_file_unref);
+                                                    (GDestroyNotify) gs_plugin_datadir_apps_cache_item_free);
 }
 
 /**
@@ -69,6 +90,25 @@ gs_plugin_destroy (GsPlugin *plugin)
 }
 
 /**
+ * gs_plugin_datadir_apps_set_from_cache_item:
+ */
+static void
+gs_plugin_datadir_apps_set_from_cache_item (GsApp *app,
+                                           GsPluginDataDirAppsCacheItem *cache_item)
+{
+       gs_app_set_id (app, cache_item->id);
+       if (cache_item->pixbuf != NULL)
+               gs_app_set_name (app, cache_item->name);
+       if (cache_item->summary != NULL)
+               gs_app_set_summary (app, cache_item->summary);
+       if (cache_item->pixbuf != NULL)
+               gs_app_set_pixbuf (app, cache_item->pixbuf);
+
+       /* mark as an application */
+       gs_app_set_kind (app, GS_APP_KIND_NORMAL);
+}
+
+/**
  * gs_plugin_datadir_apps_extract_desktop_data:
  */
 static gboolean
@@ -79,37 +119,40 @@ gs_plugin_datadir_apps_extract_desktop_data (GsPlugin *plugin,
 {
        const gchar *basename_tmp = NULL;
        gboolean ret = TRUE;
-       gboolean in_cache = FALSE;
        gchar *basename = NULL;
        gchar *comment = NULL;
        gchar *name = NULL;
        gchar *icon = NULL;
-       GKeyFile *key_file;
+       GKeyFile *key_file = NULL;
        GdkPixbuf *pixbuf = NULL;
+       GsPluginDataDirAppsCacheItem *cache_item;
 
        /* is in cache */
-       key_file = g_hash_table_lookup (plugin->priv->cache, desktop_file);
-       if (key_file != NULL) {
-               g_key_file_ref (key_file);
-               in_cache = TRUE;
-       } else {
-               /* load desktop file */
-               key_file = g_key_file_new ();
-               ret = g_key_file_load_from_file (key_file,
-                                                desktop_file,
-                                                G_KEY_FILE_NONE,
-                                                error);
-               if (!ret)
-                       goto out;
+       cache_item = g_hash_table_lookup (plugin->priv->cache, desktop_file);
+       if (cache_item != NULL) {
+               gs_plugin_datadir_apps_set_from_cache_item (app, cache_item);
+               goto out;
        }
 
+       /* load desktop file */
+       key_file = g_key_file_new ();
+       ret = g_key_file_load_from_file (key_file,
+                                        desktop_file,
+                                        G_KEY_FILE_NONE,
+                                        error);
+       if (!ret)
+               goto out;
+
+       /* create a new cache entry */
+       cache_item = g_slice_new0 (GsPluginDataDirAppsCacheItem);
+
        /* get desktop name */
        name = g_key_file_get_string (key_file,
                                      G_KEY_FILE_DESKTOP_GROUP,
                                      G_KEY_FILE_DESKTOP_KEY_NAME,
                                      NULL);
        if (name != NULL && name[0] != '\0')
-               gs_app_set_name (app, name);
+               cache_item->name = g_strdup (name);
 
        /* get desktop summary */
        comment = g_key_file_get_string (key_file,
@@ -117,7 +160,7 @@ gs_plugin_datadir_apps_extract_desktop_data (GsPlugin *plugin,
                                         G_KEY_FILE_DESKTOP_KEY_COMMENT,
                                         NULL);
        if (comment != NULL && comment[0] != '\0')
-               gs_app_set_summary (app, comment);
+               cache_item->summary = g_strdup (comment);
 
        /* get desktop icon */
        icon = g_key_file_get_string (key_file,
@@ -142,7 +185,7 @@ gs_plugin_datadir_apps_extract_desktop_data (GsPlugin *plugin,
                                                   NULL);
        }
        if (pixbuf != NULL)
-               gs_app_set_pixbuf (app, pixbuf);
+               cache_item->pixbuf = g_object_ref (pixbuf);
 
        /* set new id */
        basename = g_path_get_basename (desktop_file);
@@ -152,19 +195,16 @@ gs_plugin_datadir_apps_extract_desktop_data (GsPlugin *plugin,
                basename_tmp += 7;
        g_debug ("setting new id for %s to %s",
                 gs_app_get_id (app), basename_tmp);
-       gs_app_set_id (app, basename_tmp);
-
-       /* mark as an application */
-       gs_app_set_kind (app, GS_APP_KIND_NORMAL);
+       cache_item->id = g_strdup (basename_tmp);
 
        /* add to cache */
-       if (!in_cache) {
-               g_hash_table_insert (plugin->priv->cache,
-                                    g_strdup (desktop_file),
-                                    g_key_file_ref (key_file));
-       }
+       gs_plugin_datadir_apps_set_from_cache_item (app, cache_item);
+       g_hash_table_insert (plugin->priv->cache,
+                            g_strdup (desktop_file),
+                            cache_item);
 out:
-       g_key_file_unref (key_file);
+       if (key_file != NULL)
+               g_key_file_unref (key_file);
        if (pixbuf != NULL)
                g_object_unref (pixbuf);
        g_free (basename);