From f9b82a6fa31127cd79ea9215b6399792d0f982fc Mon Sep 17 00:00:00 2001
From: Philip Withnall <withnall@endlessm.com>
Date: Thu, 23 Nov 2017 18:48:58 +0000
Subject: [PATCH] Call gettext if .desktop file does not have inline
 translations

Patch from OpenSUSE via Ubuntu, original author unknown. Martin Pitt and
Vincent Untz appear to be the main authors.

Reworked slightly by Philip Withnall to avoid exposing new public API
for the non-standard keys.

Bug: https://bugzilla.gnome.org/show_bug.cgi?id=569829
Bug-Ubuntu: https://launchpad.net/bugs/3935
Applied-upstream: no, rejected because "this will be solved soon" (in 2013)
---
 glib/gkeyfile.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)

diff --git a/glib/gkeyfile.c b/glib/gkeyfile.c
index 6ae738c..2bc43e7 100644
--- a/glib/gkeyfile.c
+++ b/glib/gkeyfile.c
@@ -491,6 +491,17 @@
  * Since: 2.14
  */
 
+/* Downstream Debian defines for calling gettext() if a .desktop file doesn’t
+ * contain translations. These are not standardised.
+ *
+ * See: https://launchpad.net/bugs/3935
+ * See:http://bugzilla.gnome.org/show_bug.cgi?id=569829
+ */
+#define G_KEY_FILE_DESKTOP_ACTION_GROUP_PREFIX  "Desktop Action"
+#define G_KEY_FILE_DESKTOP_KEY_GETTEXT_DOMAIN   "X-GNOME-Gettext-Domain"
+#define G_KEY_FILE_DESKTOP_KEY_FULLNAME         "X-GNOME-FullName"
+#define G_KEY_FILE_DESKTOP_KEY_KEYWORDS         "Keywords"
+
 typedef struct _GKeyFileGroup GKeyFileGroup;
 
 /**
@@ -515,6 +526,7 @@ struct _GKeyFile
 
   gboolean checked_locales;  /* TRUE if @locales has been initialised */
   gchar **locales;  /* (nullable) */
+  gchar  *gettext_domain;
 
   gint ref_count;  /* (atomic) */
 };
@@ -641,6 +653,7 @@ g_key_file_init (GKeyFile *key_file)
   key_file->parse_buffer = NULL;
   key_file->list_separator = ';';
   key_file->flags = 0;
+  key_file->gettext_domain = NULL;
 }
 
 static void
@@ -661,6 +674,12 @@ g_key_file_clear (GKeyFile *key_file)
       key_file->parse_buffer = NULL;
     }
 
+  if (key_file->gettext_domain)
+    {
+       g_free (key_file->gettext_domain);
+       key_file->gettext_domain = NULL;
+    }
+
   tmp = key_file->groups;
   while (tmp != NULL)
     {
@@ -881,6 +900,11 @@ g_key_file_load_from_fd (GKeyFile       *key_file,
       return FALSE;
     }
 
+  key_file->gettext_domain = g_key_file_get_string (key_file,
+                                                    G_KEY_FILE_DESKTOP_GROUP,
+                                                    G_KEY_FILE_DESKTOP_KEY_GETTEXT_DOMAIN,
+                                                    NULL);
+
   return TRUE;
 }
 
@@ -993,6 +1017,11 @@ g_key_file_load_from_data (GKeyFile       *key_file,
       return FALSE;
     }
 
+  key_file->gettext_domain = g_key_file_get_string (key_file,
+                                                    G_KEY_FILE_DESKTOP_GROUP,
+                                                    G_KEY_FILE_DESKTOP_KEY_GETTEXT_DOMAIN,
+                                                    NULL);
+
   return TRUE;
 }
 
@@ -2242,6 +2271,8 @@ g_key_file_get_locale_string (GKeyFile     *key_file,
   GError *key_file_error;
   gchar **languages;
   gboolean free_languages = FALSE;
+  gboolean try_gettext = FALSE;
+  const gchar *msg_locale;
   gint i;
 
   g_return_val_if_fail (key_file != NULL, NULL);
@@ -2263,6 +2294,25 @@ g_key_file_get_locale_string (GKeyFile     *key_file,
       free_languages = FALSE;
     }
   
+  /* we're only interested in gettext translation if we don't have a
+   * translation in the .desktop file itself and if the key is one of the keys
+   * we know we want to translate: Name, GenericName, Comment, Keywords.
+   * Blindly doing this for all keys can give strange result for the icons,
+   * since the Icon is a locale string in the spec, eg.  We also only get
+   * translation in the mo file if the requested locale is the LC_MESSAGES one.
+   * Ideally, we should do more and change LC_MESSAGES to use the requested
+   * locale, but there's no guarantee it's installed on the system and it might
+   * have some side-effects.  Since this is a corner case, let's ignore it. */
+  msg_locale = setlocale (LC_MESSAGES, NULL);
+  try_gettext = msg_locale && key_file->gettext_domain &&
+                (strcmp (group_name, G_KEY_FILE_DESKTOP_GROUP) == 0 ||
+                 g_str_has_prefix (group_name, G_KEY_FILE_DESKTOP_ACTION_GROUP_PREFIX)) &&
+                (strcmp (key, G_KEY_FILE_DESKTOP_KEY_NAME) == 0 ||
+                 strcmp (key, G_KEY_FILE_DESKTOP_KEY_FULLNAME) == 0 ||
+                 strcmp (key, G_KEY_FILE_DESKTOP_KEY_GENERIC_NAME) == 0 ||
+                 strcmp (key, G_KEY_FILE_DESKTOP_KEY_KEYWORDS) == 0 ||
+                 strcmp (key, G_KEY_FILE_DESKTOP_KEY_COMMENT) == 0);
+
   for (i = 0; languages[i]; i++)
     {
       candidate_key = g_strdup_printf ("%s[%s]", key, languages[i]);
@@ -2276,6 +2326,39 @@ g_key_file_get_locale_string (GKeyFile     *key_file,
 	break;
    }
 
+  /* Fallback to gettext */
+  if (try_gettext && !translated_value)
+    {
+      gchar *orig_value = g_key_file_get_string (key_file, group_name, key, NULL);
+
+      if (orig_value)
+        {
+          gboolean codeset_set;
+          const gchar *translated;
+          gboolean has_gettext;
+
+          codeset_set = bind_textdomain_codeset (key_file->gettext_domain, "UTF-8") != NULL;
+          translated = NULL;
+
+          translated = g_dgettext (key_file->gettext_domain,
+                                   orig_value);
+          has_gettext = translated != orig_value;
+
+          g_free (orig_value);
+
+          if (has_gettext)
+            {
+              if (codeset_set)
+                translated_value = g_strdup (translated);
+              else
+                translated_value = g_locale_to_utf8 (translated,
+                                                     -1, NULL, NULL, NULL);
+            }
+          else
+            translated_value = NULL;
+        }
+    }
+
   /* Fallback to untranslated key
    */
   if (!translated_value)