[gnome-epub-thumbnailer] epub: Show a warning when we can't find the metafile

[Bastien Nocera <hadess src gnome org>]

commit ebd47512615b975e2a30ce45bd48cd5d01793e73
Author: Bastien Nocera <hadess hadess net>
Date:   Mon Sep 2 03:07:49 2013 +0200

    epub: Show a warning when we can't find the metafile

 gnome-epub-thumbnailer.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/gnome-epub-thumbnailer.c b/gnome-epub-thumbnailer.c
index 13cc2d9..b3e45e3 100644
--- a/gnome-epub-thumbnailer.c
+++ b/gnome-epub-thumbnailer.c
@@ -219,8 +219,10 @@ get_cover_path_from_root_file (const char *metafile,
        cover_path = NULL;
 
        root_path = get_root_file_from_metafile (metafile, length);
-       if (!root_path)
+       if (!root_path) {
+               g_warning ("Couldn't get root path for metafile %s", metafile);
                return NULL;
+       }
 
        root_file = file_get_zipped_contents (input_filename, (GCompareFunc) g_strcmp0, root_path, 
&root_length);