Start adding a unified shaper access infrastructure

Add global shape_plan.  Unused so far.

src/hb-shape-plan.cc

diff --git a/src/hb-shape-plan.cc b/src/hb-shape-plan.cc
new file mode 100644
index 0000000..b96d5f2
--- /dev/null
+++ b/src/hb-shape-plan.cc
@@ -0,0 +1,85 @@
+/*
+ * Copyright © 2012  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#include "hb-private.hh"
+
+#include "hb-shape-plan-private.hh"
+
+#include "hb-font-private.hh"
+
+
+/*
+ * hb_shape_plan_t
+ */
+
+hb_shape_plan_t *
+hb_shape_plan_create (hb_face_t                     *face,
+		      const hb_segment_properties_t *props,
+		      const hb_feature_t            *user_features,
+		      unsigned int                   num_user_features,
+		      const char * const            *shaper_list)
+{
+  hb_shape_plan_t *shape_plan;
+
+  if (unlikely (!face))
+    face = hb_face_get_empty ();
+  if (unlikely (!props || hb_object_is_inert (face)))
+    return hb_shape_plan_get_empty ();
+  if (!(shape_plan = hb_object_create<hb_shape_plan_t> ()))
+    return hb_shape_plan_get_empty ();
+
+  hb_face_make_immutable (face);
+
+  return shape_plan;
+}
+
+hb_shape_plan_t *
+hb_shape_plan_get_empty (void)
+{
+  static const hb_shape_plan_t _hb_shape_plan_nil = {
+    HB_OBJECT_HEADER_STATIC,
+  };
+
+  return const_cast<hb_shape_plan_t *> (&_hb_shape_plan_nil);
+}
+
+hb_shape_plan_t *
+hb_shape_plan_reference (hb_shape_plan_t *shape_plan)
+{
+  return hb_object_reference (shape_plan);
+}
+
+void
+hb_shape_plan_destroy (hb_shape_plan_t *shape_plan)
+{
+  if (!hb_object_destroy (shape_plan)) return;
+
+#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_DESTROY(shaper, shape_plan);
+#include "hb-shaper-list.hh"
+#undef HB_SHAPER_IMPLEMENT
+
+  free (shape_plan);
+}