gegl r2165 - in trunk: . gegl/buffer

[ok svn gnome org]

Author: ok
Date: Mon Apr 14 21:36:14 2008
New Revision: 2165
URL: http://svn.gnome.org/viewvc/gegl?rev=2165&view=rev

Log:
* gegl/buffer/Makefile.am:
* gegl/buffer/gegl-id-pool.[ch]: added a data structure to keep track
of reusable unique integer ids for pointers.


Added:
   trunk/gegl/buffer/gegl-id-pool.c
   trunk/gegl/buffer/gegl-id-pool.h
Modified:
   trunk/ChangeLog
   trunk/gegl/buffer/Makefile.am

Modified: trunk/gegl/buffer/Makefile.am
==============================================================================
--- trunk/gegl/buffer/Makefile.am	(original)
+++ trunk/gegl/buffer/Makefile.am	Mon Apr 14 21:36:14 2008
@@ -24,6 +24,7 @@
     gegl-handler-empty.c	\
     gegl-handler-log.c		\
     gegl-handler-zoom.c		\
+    gegl-id-pool.c		\
     gegl-provider.c
 
 BUFFER_headers = \
@@ -52,6 +53,7 @@
     gegl-handler-empty.h	\
     gegl-handler-log.h		\
     gegl-handler-zoom.h		\
+    gegl-id-pool.h		\
     gegl-provider.h
 
 libbuffer_la_SOURCES = $(BUFFER_sources) $(BUFFER_headers)

Added: trunk/gegl/buffer/gegl-id-pool.c
==============================================================================
--- (empty file)
+++ trunk/gegl/buffer/gegl-id-pool.c	Mon Apr 14 21:36:14 2008
@@ -0,0 +1,122 @@
+/*
+ * Gegl id-pool
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * GeglIDPool: pool of reusable integer ids associated with pointers.
+ *
+ * Copyright (C) 2008 OpenedHand
+ * Author: Ãyvind KolÃs <pippin o-hand-com>
+ *
+ */
+
+#define DEBUG_POOL
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "gegl-id-pool.h"
+
+struct _GeglIDPool
+{
+  GArray *array;     /* Array of pointers    */
+  GSList *free_ids;  /* A stack of freed ids */
+};
+
+GeglIDPool *
+gegl_id_pool_new  (guint initial_size)
+{
+  GeglIDPool *self;
+
+  self = g_slice_new (GeglIDPool);
+
+  self->array = g_array_sized_new (FALSE, FALSE, 
+                                   sizeof (gpointer), initial_size);
+  self->free_ids = NULL;
+  return self;
+}
+
+void
+gegl_id_pool_free (GeglIDPool *id_pool)
+{
+  g_return_if_fail (id_pool != NULL);
+
+  g_array_free (id_pool->array, TRUE);
+  g_slist_free (id_pool->free_ids);
+  g_slice_free (GeglIDPool, id_pool);
+}
+
+guint32
+gegl_id_pool_add (GeglIDPool *id_pool,
+                  gpointer    ptr)
+{
+  gpointer *array;
+  guint32   id;
+
+  g_return_val_if_fail (id_pool != NULL, 0);
+
+  if (id_pool->free_ids) /* There are items on our freelist, reuse one */
+    {
+      array = (void*) id_pool->array->data;
+      id = GPOINTER_TO_UINT (id_pool->free_ids->data);
+
+      id_pool->free_ids = g_slist_remove (id_pool->free_ids,
+                                          id_pool->free_ids->data);
+      array[id] = ptr;
+      return id;
+    }
+
+  /* Allocate new id */
+  id = id_pool->array->len;
+  g_array_append_val (id_pool->array, ptr);
+  return id;
+}
+
+void
+gegl_id_pool_remove (GeglIDPool *id_pool,
+                     guint32     id)
+{
+  gpointer *array;
+#ifdef DEBUG_POOL
+  return;
+#endif
+
+  g_return_if_fail (id_pool != NULL);
+  array = (void*) id_pool->array->data;
+
+  array[id] = (void*)0xdecafbad;   /* set pointer to a recognizably voided
+                                      value */
+
+  id_pool->free_ids = g_slist_prepend (id_pool->free_ids,
+                                       GUINT_TO_POINTER (id));
+}
+
+gpointer
+gegl_id_pool_lookup (GeglIDPool *id_pool,
+                     guint32     id)
+{
+  gpointer *array;
+
+  g_return_val_if_fail (id_pool != NULL, NULL);
+  g_return_val_if_fail (id_pool->array != NULL, NULL);
+
+  g_return_val_if_fail (id < id_pool->array->len, NULL);
+
+  array = (void*) id_pool->array->data;
+
+  return array[id];
+}

Added: trunk/gegl/buffer/gegl-id-pool.h
==============================================================================
--- (empty file)
+++ trunk/gegl/buffer/gegl-id-pool.h	Mon Apr 14 21:36:14 2008
@@ -0,0 +1,50 @@
+/* GEGL - 
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * GeglIDPool: pool of reusable integer ids associated with pointers.
+ *
+ * Author: Ãyvind KolÃs <pippin o-hand com>
+ *
+ * Clutter
+ * An OpenGL based 'interactive canvas' library.
+ * Authored By Matthew Allum  <mallum openedhand com>
+ *
+ * Copyright (C) 2008 OpenedHand
+ */
+
+#ifndef __GEGL_ID_POOL_H__
+#define __GEGL_ID_POOL_H__
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+typedef struct _GeglIDPool   GeglIDPool;
+
+GeglIDPool *gegl_id_pool_new     (guint       initial_size);
+void        gegl_id_pool_free    (GeglIDPool *id_pool);
+guint32     gegl_id_pool_add     (GeglIDPool *id_pool,
+                                  gpointer    ptr);
+void        gegl_id_pool_remove  (GeglIDPool *id_pool,
+                                  guint32     id);
+gpointer    gegl_id_pool_lookup  (GeglIDPool *id_pool,
+                                  guint32     id);
+
+
+G_END_DECLS
+
+#endif /* __CLUTTER_ID_POOL_H__ */