libvlc: media: set sub_items readonly

media's sub_items should be only writable by media.
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

lib/media.c

@@ -43,6 +43,7 @@
 
 #include "libvlc_internal.h"
 #include "media_internal.h"
+#include "media_list_internal.h"
 
 static const vlc_meta_type_t libvlc_to_vlc_meta[] =
 {
@@ -112,7 +113,10 @@ static libvlc_media_list_t *media_get_subitems( libvlc_media_t * p_md )
     {
         p_md->p_subitems = libvlc_media_list_new( p_md->p_libvlc_instance );
         if( p_md->p_subitems != NULL )
+        {
+            p_md->p_subitems->b_read_only = true;
             libvlc_media_list_set_media( p_md->p_subitems, p_md );
+        }
     }
     p_subitems = p_md->p_subitems;
     vlc_mutex_unlock( &p_md->subitems_lock );
@@ -137,7 +141,7 @@ static void input_item_subitem_added( const vlc_event_t *p_event,
     /* Add this to our media list */
     p_subitems = media_get_subitems( p_md );
     if( p_subitems != NULL )
-        libvlc_media_list_add_media( p_subitems, p_md_child );
+        libvlc_media_list_internal_add_media( p_subitems, p_md_child );
 
     /* Construct the event */
     event.type = libvlc_MediaSubItemAdded;