Add libvlc_media_list_player_retain() to libvlc.

There was only release() before.
Signed-off-by: Rémi Duraffort <ivoire@videolan.org>

include/vlc/libvlc_media_list_player.h

@@ -68,13 +68,26 @@ LIBVLC_API libvlc_media_list_player_t *
     libvlc_media_list_player_new( libvlc_instance_t * p_instance );
 
 /**
- * Release media_list_player.
+ * Release a media_list_player after use
+ * Decrement the reference count of a media player object. If the
+ * reference count is 0, then libvlc_media_list_player_release() will
+ * release the media player object. If the media player object
+ * has been released, then it should not be used again.
  *
  * \param p_mlp media list player instance
  */
 LIBVLC_API void
     libvlc_media_list_player_release( libvlc_media_list_player_t * p_mlp );
 
+/**
+ * Retain a reference to a media player list object. Use
+ * libvlc_media_list_player_release() to decrement reference count.
+ *
+ * \param p_mlp media player list object
+ */
+LIBVLC_API void
+    libvlc_media_list_player_retain( libvlc_media_list_player_t *p_mlp );
+
 /**
  * Return the event manager of this media_list_player.
  *

src/control/media_list_player.c

@@ -519,6 +519,19 @@ void libvlc_media_list_player_release(libvlc_media_list_player_t * p_mlp)
     free(p_mlp);
 }
 
+/**************************************************************************
+ *        retain (Public)
+ **************************************************************************/
+void libvlc_media_list_player_retain(libvlc_media_list_player_t * p_mlp)
+{
+    if (!p_mlp)
+        return;
+
+    lock(p_mlp);
+    p_mlp->i_refcount++;
+    unlock(p_mlp);
+}
+
 /**************************************************************************
  *        event_manager (Public)
  **************************************************************************/

src/libvlc.sym

@@ -95,6 +95,7 @@ libvlc_media_list_player_play_item
 libvlc_media_list_player_play_item_at_index
 libvlc_media_list_player_previous
 libvlc_media_list_player_release
+libvlc_media_list_player_retain
 libvlc_media_list_player_set_media_list
 libvlc_media_list_player_set_media_player
 libvlc_media_list_player_set_playback_mode