iconcache: Use GDesktopAppInfo to find correct application icons

Some files do not report their application icons correctly in the window
properties. This patch allows the marco UI to search for the
corresponding .desktop file and render the icon in the desktop info on
both the alt-tab popup and the window mini-icon.

1 files changed, 74 insertions, 0 deletions

diff --git a/src/ui/ui.c b/src/ui/ui.c
index 44c72938..4935f77c 100644
--- a/src/ui/ui.c
+++ b/src/ui/ui.c
@@ -32,6 +32,7 @@
 #include <stdlib.h>
 
 #include <cairo-xlib.h>
+#include <gio/gdesktopappinfo.h>
 
 static void meta_ui_accelerator_parse(const char* accel, guint* keysym, guint* keycode, GdkModifierType* keymask);
 
@@ -647,6 +648,79 @@ meta_ui_get_default_mini_icon (MetaUI *ui)
   return default_icon;
 }
 
+static GdkPixbuf *
+load_window_icon_from_name (char *name, int size, int scale)
+{
+  GtkIconTheme *theme = gtk_icon_theme_get_default ();
+  GdkPixbuf *pixbuf = NULL;
+
+  /* If the res_name window property maps to an icon, use that */
+  pixbuf = gtk_icon_theme_load_icon_for_scale (theme, name, size, scale, GTK_ICON_LOOKUP_FORCE_SIZE, NULL);
+  if (pixbuf != NULL)
+    return pixbuf;
+
+  char ***results;
+  gchar *desktop_id = NULL;
+  gint i, j;
+  GDesktopAppInfo *info;
+  GIcon *gicon;
+  GtkIconInfo *icon_info;
+
+  /* Find a proper desktop file based on the window property name */
+  results = g_desktop_app_info_search (name);
+
+  for (i = 0; results[i]; i++)
+    {
+      for (j = 0; results[i][j]; j++)
+        {
+          /* We are only interested in the top ranking result, so we use that and free up the rest */
+          if (desktop_id == NULL)
+            desktop_id = g_strdup(results[i][j]);
+        }
+      g_strfreev (results[i]);
+    }
+  g_free (results);
+
+  if (desktop_id == NULL)
+    return NULL;
+
+  /* Now that we have the desktop file ID, we extract the icon from it and render it */
+  info = g_desktop_app_info_new (desktop_id);
+  gicon = g_app_info_get_icon (G_APP_INFO (info));
+  icon_info = gtk_icon_theme_lookup_by_gicon_for_scale (theme, gicon, size, scale, GTK_ICON_LOOKUP_FORCE_SIZE);
+
+  pixbuf = gtk_icon_info_load_icon (icon_info, NULL);
+
+  g_object_unref (icon_info);
+  g_free (desktop_id);
+
+  return pixbuf;
+}
+
+GdkPixbuf*
+meta_ui_get_window_icon_from_name (MetaUI *ui, char *name)
+{
+  int scale;
+  int size;
+
+  scale = gtk_widget_get_scale_factor (GTK_WIDGET (ui->frames));
+  size = meta_prefs_get_icon_size() / scale;
+
+  return load_window_icon_from_name (name, size, scale);
+}
+
+GdkPixbuf*
+meta_ui_get_mini_icon_from_name (MetaUI *ui, char *name)
+{
+  int scale;
+  int size;
+
+  scale = gtk_widget_get_scale_factor (GTK_WIDGET (ui->frames));
+  size = META_MINI_ICON_WIDTH / scale;
+
+  return load_window_icon_from_name (name, size, scale);
+}
+
 gboolean
 meta_ui_window_should_not_cause_focus (Display *xdisplay,
                                        Window   xwindow)