[gegl] buffer: add a command to the tile architecture for reiniting

[Ãyvind KolÃs <ok src gnome org>]

commit db43a7d8a42f0ae1ecc29fc4f8dcb4180da02ea2
Author: Ãyvind KolÃs <pippin gimp org>
Date:   Wed Mar 14 00:03:02 2012 +0000

    buffer: add a command to the tile architecture for reiniting
    
    This is meant to be called from a tile backend to cause GeglBuffer to drop all
    cached tiles.

 gegl/buffer/gegl-buffer-private.h     |    1 +
 gegl/buffer/gegl-tile-backend-file.c  |   13 +++------
 gegl/buffer/gegl-tile-backend.c       |    6 ++++
 gegl/buffer/gegl-tile-backend.h       |    3 ++
 gegl/buffer/gegl-tile-handler-cache.c |   45 +++++++++++++++++++++++++++++++++
 gegl/buffer/gegl-tile-source.h        |   12 +++++++++
 6 files changed, 71 insertions(+), 9 deletions(-)
---
diff --git a/gegl/buffer/gegl-buffer-private.h b/gegl/buffer/gegl-buffer-private.h
index 4acd333..11323ed 100644
--- a/gegl/buffer/gegl-buffer-private.h
+++ b/gegl/buffer/gegl-buffer-private.h
@@ -174,6 +174,7 @@ struct _GeglTile
   gpointer         unlock_notify_data;
 };
 
+
 #ifndef __GEGL_TILE_C
 #define gegl_tile_get_data(tile)  ((guchar*)((tile)->data))
 #endif // __GEGL_TILE_C
diff --git a/gegl/buffer/gegl-tile-backend-file.c b/gegl/buffer/gegl-tile-backend-file.c
index d835244..63d6105 100644
--- a/gegl/buffer/gegl-tile-backend-file.c
+++ b/gegl/buffer/gegl-tile-backend-file.c
@@ -789,14 +789,12 @@ gegl_tile_backend_file_load_index (GeglTileBackendFile *self,
             }
           else
             {
+              GeglTileStorage *storage =
+                (void*)gegl_tile_backend_peek_storage (backend);
               GeglRectangle rect;
               g_hash_table_remove (self->index, existing);
 
-              /* XXX: this refetch, depends on knowing the storage, the
-               * storage should not be public information/API to maintain
-               * proper encapsulation
-               */
-              gegl_tile_source_refetch (GEGL_TILE_SOURCE (backend->priv->storage),
+              gegl_tile_source_refetch (GEGL_TILE_SOURCE (storage),
                                         existing->tile.x,
                                         existing->tile.y,
                                         existing->tile.z);
@@ -810,10 +808,7 @@ gegl_tile_backend_file_load_index (GeglTileBackendFile *self,
                 }
               g_free (existing);
 
-              /* XXX: this emitting of changed depends on knowing the storage,
-               * which is icky..
-               */
-              g_signal_emit_by_name (backend->priv->storage, "changed", &rect, NULL);
+              g_signal_emit_by_name (storage, "changed", &rect, NULL);
             }
         }
       g_hash_table_insert (self->index, iter->data, iter->data);
diff --git a/gegl/buffer/gegl-tile-backend.c b/gegl/buffer/gegl-tile-backend.c
index 655ac42..ddfe320 100644
--- a/gegl/buffer/gegl-tile-backend.c
+++ b/gegl/buffer/gegl-tile-backend.c
@@ -22,6 +22,7 @@
 
 #include <babl/babl.h>
 #include "gegl-buffer-types.h"
+#include "gegl-buffer-private.h"
 #include "gegl-tile-source.h"
 #include "gegl-tile-backend.h"
 
@@ -193,3 +194,8 @@ GeglRectangle gegl_tile_backend_get_extent (GeglTileBackend *tile_backend)
 {
   return tile_backend->priv->extent;
 }
+
+GeglTileSource *gegl_tile_backend_peek_storage (GeglTileBackend *backend)
+{
+  return backend->priv->storage;
+}
diff --git a/gegl/buffer/gegl-tile-backend.h b/gegl/buffer/gegl-tile-backend.h
index 8e9fb35..ebf59e6 100644
--- a/gegl/buffer/gegl-tile-backend.h
+++ b/gegl/buffer/gegl-tile-backend.h
@@ -54,6 +54,9 @@ struct _GeglTileBackendClass
 gint  gegl_tile_backend_get_tile_size (GeglTileBackend *tile_backend);
 Babl *gegl_tile_backend_get_format    (GeglTileBackend *tile_backend);
 
+/* gets a pointer to the GeglTileStorage that uses the backend */
+GeglTileSource *gegl_tile_backend_peek_storage  (GeglTileBackend *backend);
+
 /* specify the extent of the backend, can be used to
  * pre-prime the backend with the width/height information when
  * constructing proxy GeglBuffers to interact with other systems
diff --git a/gegl/buffer/gegl-tile-handler-cache.c b/gegl/buffer/gegl-tile-handler-cache.c
index c576425..574ad6e 100644
--- a/gegl/buffer/gegl-tile-handler-cache.c
+++ b/gegl/buffer/gegl-tile-handler-cache.c
@@ -111,6 +111,48 @@ gegl_tile_handler_cache_init (GeglTileHandlerCache *cache)
   gegl_tile_cache_init ();
 }
 
+
+static void
+gegl_tile_handler_cache_reinit_buffer_tiles (gpointer itm,
+                                             gpointer userdata)
+{
+  CacheItem *item;
+  item = itm;
+  if (item->handler == userdata)
+    {
+      GeglTileHandlerCache *cache = userdata;
+      cache->free_list = g_slist_prepend (cache->free_list, item);
+    }
+}
+
+static void
+gegl_tile_handler_cache_reinit (GeglTileHandlerCache *cache)
+{
+  CacheItem            *item;
+  GSList               *iter;
+
+  g_static_mutex_lock (&mutex);
+  /* only throw out items belonging to this cache instance */
+  cache->free_list = NULL;
+  g_queue_foreach (cache_queue, gegl_tile_handler_cache_reinit_buffer_tiles, cache);
+  for (iter = cache->free_list; iter; iter = g_slist_next (iter))
+    {
+      item = iter->data;
+      if (item->tile)
+        {
+          cache_total -= item->tile->size;
+          gegl_tile_mark_as_stored (item->tile); /* to avoid saving */
+          gegl_tile_unref (item->tile);
+        }
+      g_queue_remove (cache_queue, item);
+      g_hash_table_remove (cache_ht, item);
+      g_slice_free (CacheItem, item);
+    }
+  g_slist_free (cache->free_list);
+  cache->free_list = NULL;
+  g_static_mutex_unlock (&mutex);
+}
+
 static void
 gegl_tile_handler_cache_dispose_buffer_tiles (gpointer itm,
                                               gpointer userdata)
@@ -251,6 +293,9 @@ gegl_tile_handler_cache_command (GeglTileSource  *tile_store,
       case GEGL_TILE_VOID:
         gegl_tile_handler_cache_void (cache, x, y, z);
         break;
+      case GEGL_TILE_REINIT:
+        gegl_tile_handler_cache_reinit (cache);
+        break;
       default:
         break;
     }
diff --git a/gegl/buffer/gegl-tile-source.h b/gegl/buffer/gegl-tile-source.h
index 2dd6d86..4152e52 100644
--- a/gegl/buffer/gegl-tile-source.h
+++ b/gegl/buffer/gegl-tile-source.h
@@ -81,6 +81,7 @@ enum _GeglTileCommand
   GEGL_TILE_VOID,
   GEGL_TILE_FLUSH,
   GEGL_TILE_REFETCH,
+  GEGL_TILE_REINIT,
   GEGL_TILE_LAST_COMMAND
 };
 
@@ -149,6 +150,15 @@ gboolean  gegl_tile_source_exist     (GeglTileSource *source,
                                       gint            x,
                                       gint            y,
                                       gint            z);
+
+/**
+ * gegl_tile_source_reinit:
+ * @source: a GeglTileSource *
+ *
+ * Causes all tiles in cache to be refetched.
+ */
+void      gegl_tile_source_reinit    (GeglTileSource *source);
+
 /**
  * gegl_tile_source_void:
  * @source: a GeglTileSource *
@@ -206,6 +216,8 @@ gboolean  gegl_tile_source_idle      (GeglTileSource *source);
    gegl_tile_source_command(source,GEGL_TILE_VOID,x,y,z,NULL)
 #define gegl_tile_source_refetch(source,x,y,z) \
    gegl_tile_source_command(source,GEGL_TILE_REFETCH,x,y,z,NULL)
+#define gegl_tile_source_reinit(source) \
+   gegl_tile_source_command(source,GEGL_TILE_REINIT,0,0,0,NULL)
 #define gegl_tile_source_idle(source) \
    (gboolean)GPOINTER_TO_INT(gegl_tile_source_command(source,GEGL_TILE_IDLE,0,0,0,NULL))