[gegl/soc-2012-ops] buffer: add preliminary gegl_buffer_add, remove_handler()

[Maxime Nicco <maxnicco src gnome org>]

commit f6f81d9a35045a94eade3bc18ed1c87128fca241
Author: Michael Natterer <mitch gimp org>
Date:   Thu Jul 5 21:33:18 2012 +0200

    buffer: add preliminary gegl_buffer_add,remove_handler()
    
    mostly for discussion and getting the GIMP projection patch
    some public testing.
    
    NOTE: this API will change.

 gegl/buffer/gegl-buffer.c |   44 ++++++++++++++++++++++++++++++++++++++++++++
 gegl/buffer/gegl-buffer.h |    5 +++++
 2 files changed, 49 insertions(+), 0 deletions(-)
---
diff --git a/gegl/buffer/gegl-buffer.c b/gegl/buffer/gegl-buffer.c
index c3e1c6b..dc71186 100644
--- a/gegl/buffer/gegl-buffer.c
+++ b/gegl/buffer/gegl-buffer.c
@@ -1090,6 +1090,50 @@ gegl_buffer_new_for_backend (const GeglRectangle *extent,
                        NULL);
 }
 
+void
+gegl_buffer_add_handler (GeglBuffer *buffer,
+                         gpointer    handler)
+{
+  GeglTileHandlerChain *chain;
+
+  g_return_if_fail (GEGL_IS_BUFFER (buffer));
+  g_return_if_fail (GEGL_IS_TILE_HANDLER (handler));
+
+  g_object_set (handler,
+                "format", buffer->tile_storage->format,
+                "tile-width", buffer->tile_storage->tile_width,
+                "tile-height", buffer->tile_storage->tile_height,
+                NULL);
+
+  chain = GEGL_TILE_HANDLER_CHAIN (buffer->tile_storage);
+
+  gegl_tile_handler_chain_add (chain, handler);
+
+  /* XXX */
+  chain->chain = g_slist_remove (chain->chain, handler);
+  chain->chain = g_slist_insert (chain->chain, handler, 2);
+
+  gegl_tile_handler_chain_bind (chain);
+}
+
+void
+gegl_buffer_remove_handler (GeglBuffer *buffer,
+                            gpointer    handler)
+{
+  GeglTileHandlerChain *chain;
+
+  g_return_if_fail (GEGL_IS_BUFFER (buffer));
+  g_return_if_fail (GEGL_IS_TILE_HANDLER (handler));
+
+  chain = GEGL_TILE_HANDLER_CHAIN (buffer->tile_storage);
+
+  g_return_if_fail (g_slist_find (chain->chain, handler));
+
+  chain->chain = g_slist_remove (chain->chain, handler);
+  g_object_unref (handler);
+
+  gegl_tile_handler_chain_bind (chain);
+}
 
 /* FIXME: this function needs optimizing, perhaps keep a pool
  * of GeglBuffer shells that can be adapted to the needs
diff --git a/gegl/buffer/gegl-buffer.h b/gegl/buffer/gegl-buffer.h
index c35dfa6..32d2e1a 100644
--- a/gegl/buffer/gegl-buffer.h
+++ b/gegl/buffer/gegl-buffer.h
@@ -77,6 +77,11 @@ GeglBuffer *    gegl_buffer_new               (const GeglRectangle *extent,
 GeglBuffer *   gegl_buffer_new_for_backend    (const GeglRectangle *extent,
                                                void                *backend);
 
+void           gegl_buffer_add_handler        (GeglBuffer          *buffer,
+                                               gpointer             handler);
+void           gegl_buffer_remove_handler     (GeglBuffer          *buffer,
+                                               gpointer             handler);
+
 /**
  * gegl_buffer_open:
  * @path: the path to a gegl buffer on disk.