GAppInfo: add a mechanism to query supported content types

This essentially adds an accessor for the MimeType field in desktop files,
to retrieve the list of all mime types supported by an application.
The interface though is part of GAppInfo, so it could be implemented
in the future by other backends.

https://bugzilla.gnome.org/show_bug.cgi?id=674111

docs/reference/gio/gio-sections.txt

@@ -1313,6 +1313,7 @@ g_app_info_set_as_last_used_for_type
 g_app_info_add_supports_type
 g_app_info_can_remove_supports_type
 g_app_info_remove_supports_type
+g_app_info_get_supported_types
 g_app_info_get_all
 g_app_info_get_all_for_type
 g_app_info_get_default_for_type

gio/gappinfo.c

@@ -458,6 +458,37 @@ g_app_info_remove_supports_type (GAppInfo    *appinfo,
   return FALSE;
 }
 
+/**
+ * g_app_info_get_supported_types:
+ * @info: a #GAppInfo that can handle files
+ *
+ * Retrieves the list of content types that @app_info claims to support.
+ * If this information is not provided by the environment, this function
+ * will return %NULL.
+ * This function does not take in consideration associations added with
+ * g_app_info_add_supports_type(), but only those exported directly by
+ * the application.
+ *
+ * Returns: (transfer none) (array zero-terminated=1) (element-type utf8):
+ *    a list of content types.
+ *
+ * Since: 2.34
+ */
+const char **
+g_app_info_get_supported_types (GAppInfo *appinfo)
+{
+  GAppInfoIface *iface;
+
+  g_return_val_if_fail (G_IS_APP_INFO (appinfo), NULL);
+
+  iface = G_APP_INFO_GET_IFACE (appinfo);
+
+  if (iface->get_supported_types)
+    return iface->get_supported_types (appinfo);
+  else
+    return NULL;
+}
+
 
 /**
  * g_app_info_get_icon:

gio/gappinfo.h

@@ -132,6 +132,7 @@ struct _GAppInfoIface
   gboolean     (* set_as_last_used_for_type)    (GAppInfo           *appinfo,
                                                  const char         *content_type,
                                                  GError            **error);
+  const char ** (* get_supported_types)         (GAppInfo           *appinfo);
 };
 
 GType       g_app_info_get_type                     (void) G_GNUC_CONST;
@@ -174,6 +175,9 @@ gboolean    g_app_info_can_remove_supports_type     (GAppInfo             *appin
 gboolean    g_app_info_remove_supports_type         (GAppInfo             *appinfo,
                                                      const char           *content_type,
                                                      GError              **error);
+GLIB_AVAILABLE_IN_2_34
+const char **g_app_info_get_supported_types         (GAppInfo             *appinfo);
+
 gboolean    g_app_info_can_delete                   (GAppInfo   *appinfo);
 gboolean    g_app_info_delete                       (GAppInfo   *appinfo);
 

gio/gdesktopappinfo.c

@@ -108,6 +108,7 @@ struct _GDesktopAppInfo
   char *path;
   char *categories;
   char *startup_wm_class;
+  char **mime_types;
 
   guint nodisplay       : 1;
   guint hidden          : 1;
@@ -187,6 +188,7 @@ g_desktop_app_info_finalize (GObject *object)
   g_free (info->path);
   g_free (info->categories);
   g_free (info->startup_wm_class);
+  g_strfreev (info->mime_types);
   
   G_OBJECT_CLASS (g_desktop_app_info_parent_class)->finalize (object);
 }
@@ -333,6 +335,7 @@ g_desktop_app_info_load_from_keyfile (GDesktopAppInfo *info,
   info->hidden = g_key_file_get_boolean (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_HIDDEN, NULL) != FALSE;
   info->categories = g_key_file_get_string (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_CATEGORIES, NULL);
   info->startup_wm_class = g_key_file_get_string (key_file, G_KEY_FILE_DESKTOP_GROUP, STARTUP_WM_CLASS_KEY, NULL);
+  info->mime_types = g_key_file_get_string_list (key_file, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_MIME_TYPE, NULL, NULL);
   
   info->icon = NULL;
   if (info->icon_name)
@@ -1981,6 +1984,15 @@ g_desktop_app_info_remove_supports_type (GAppInfo    *appinfo,
                                error);
 }
 
+static const char **
+g_desktop_app_info_get_supported_types (GAppInfo *appinfo)
+{
+  GDesktopAppInfo *info = G_DESKTOP_APP_INFO (appinfo);
+
+  return (const char**) info->mime_types;
+}
+
+
 static gboolean
 g_desktop_app_info_ensure_saved (GDesktopAppInfo  *info,
 				 GError          **error)
@@ -2202,6 +2214,7 @@ g_desktop_app_info_iface_init (GAppInfoIface *iface)
   iface->get_commandline = g_desktop_app_info_get_commandline;
   iface->get_display_name = g_desktop_app_info_get_display_name;
   iface->set_as_last_used_for_type = g_desktop_app_info_set_as_last_used_for_type;
+  iface->get_supported_types = g_desktop_app_info_get_supported_types;
 }
 
 static gboolean

gio/gio.symbols

@@ -56,6 +56,7 @@ g_app_info_get_description
 g_app_info_get_executable
 g_app_info_get_commandline
 g_app_info_get_icon
+g_app_info_get_supported_types
 g_app_info_launch
 g_app_info_supports_uris
 g_app_info_supports_files

gio/tests/appinfo-test.desktop

@@ -10,3 +10,4 @@ Exec=./appinfo-test --option
 Icon=testicon
 StartupNotify=true
 StartupWMClass=appinfo-class
+MimeType=image/png;image/jpeg;

gio/tests/appinfo.c

@@ -287,6 +287,21 @@ test_startup_wm_class (void)
   g_object_unref (appinfo);
 }
 
+static void
+test_supported_types (void)
+{
+  GAppInfo *appinfo;
+  const char * const *content_types;
+
+  appinfo = G_APP_INFO (g_desktop_app_info_new_from_filename (SRCDIR "/appinfo-test.desktop"));
+  content_types = g_app_info_get_supported_types (appinfo);
+
+  g_assert_cmpint (g_strv_length ((char**)content_types), ==, 2);
+  g_assert_cmpstr (content_types[0], ==, "image/png");
+
+  g_object_unref (appinfo);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -303,6 +318,7 @@ main (int argc, char *argv[])
   g_test_add_func ("/appinfo/associations", test_associations);
   g_test_add_func ("/appinfo/environment", test_environment);
   g_test_add_func ("/appinfo/startup-wm-class", test_startup_wm_class);
+  g_test_add_func ("/appinfo/supported-types", test_supported_types);
 
   return g_test_run ();
 }