[glib] GDesktopAppInfo: support bus activation with '-'

[Allison Ryan Lortie <desrt src gnome org>]

commit 3301b852a20b3d1f75592d03dd4038d3ea2fed7c
Author: Allison Ryan Lortie <desrt desrt ca>
Date:   Tue Apr 12 11:06:11 2016 -0400

    GDesktopAppInfo: support bus activation with '-'
    
    GApplication has accepted any valid bus name as an application ID since
    before the time of D-Bus activation.  This includes bus names with '-'.
    Several applications have even attempted support bus activation with
    these names, going as far as installing D-Bus service files, without
    realising that they are silently falling back to fork()/exec() on
    account of the name containing a dash.
    
    The reason for the problem is that D-Bus object paths cannot contain
    dashes.  We solved this problem privately in an unspecified way inside
    of GApplication but substituting '_' in this case, but never made this
    part of the Desktop Entry Specification.
    
    The fact that these apps with '-' in the desktop file names aren't
    actually using D-Bus activation is beside the point: their intent here
    was clear.  Let's avoid forcing them to rename their desktop files again
    by simply accepting '-' in desktop file names and munging the path in
    the way that GApplication did so historically.
    
    The new path escaping code here has been copied more or less verbatim
    from GApplication's own code for the same purpose, with only the removal
    of one irrelevant part.
    
    An update to the desktop entry specification will follow.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=764754

 gio/gdesktopappinfo.c |   28 ++++++++++++----------------
 1 files changed, 12 insertions(+), 16 deletions(-)
---
diff --git a/gio/gdesktopappinfo.c b/gio/gdesktopappinfo.c
index ac9c7eb..d65288d 100644
--- a/gio/gdesktopappinfo.c
+++ b/gio/gdesktopappinfo.c
@@ -1794,7 +1794,7 @@ g_desktop_app_info_load_from_keyfile (GDesktopAppInfo *info,
         {
           *last_dot = '\0';
 
-          if (g_dbus_is_interface_name (basename))
+          if (g_dbus_is_name (basename) && basename[0] != ':')
             info->app_id = g_strdup (basename);
         }
 
@@ -2785,25 +2785,21 @@ g_desktop_app_info_launch_uris_with_spawn (GDesktopAppInfo            *info,
 }
 
 static gchar *
-object_path_from_appid (const gchar *app_id)
+object_path_from_appid (const gchar *appid)
 {
-  gchar *path;
-  gint i, n;
+  gchar *appid_path, *iter;
 
-  n = strlen (app_id);
-  path = g_malloc (n + 2);
-
-  path[0] = '/';
-
-  for (i = 0; i < n; i++)
-    if (app_id[i] != '.')
-      path[i + 1] = app_id[i];
-    else
-      path[i + 1] = '/';
+  appid_path = g_strconcat ("/", appid, NULL);
+  for (iter = appid_path; *iter; iter++)
+    {
+      if (*iter == '.')
+        *iter = '/';
 
-  path[i + 1] = '\0';
+      if (*iter == '-')
+        *iter = '_';
+    }
 
-  return path;
+  return appid_path;
 }
 
 static GVariant *