1 /*
   2  * Copyright © 2012  Google, Inc.
   3  *
   4  *  This is part of HarfBuzz, a text shaping library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  *
  24  * Google Author(s): Behdad Esfahbod
  25  */
  26 
  27 #ifndef HB_SHAPER_HH
  28 #define HB_SHAPER_HH
  29 
  30 #include "hb.hh"
  31 #include "hb-machinery.hh"
  32 
  33 typedef hb_bool_t hb_shape_func_t (hb_shape_plan_t    *shape_plan,
  34                                    hb_font_t          *font,
  35                                    hb_buffer_t        *buffer,
  36                                    const hb_feature_t *features,
  37                                    unsigned int        num_features);
  38 
  39 #define HB_SHAPER_IMPLEMENT(name) \
  40         extern "C" HB_INTERNAL hb_shape_func_t _hb_##name##_shape;
  41 #include "hb-shaper-list.hh"
  42 #undef HB_SHAPER_IMPLEMENT
  43 
  44 struct hb_shaper_entry_t {
  45   char name[16];
  46   hb_shape_func_t *func;
  47 };
  48 
  49 HB_INTERNAL const hb_shaper_entry_t *
  50 _hb_shapers_get ();
  51 
  52 
  53 template <typename Data, unsigned int WheresData, typename T>
  54 struct hb_shaper_lazy_loader_t;
  55 
  56 #define HB_SHAPER_ORDER(Shaper) \
  57   HB_PASTE (HB_SHAPER_ORDER_, Shaper)
  58 enum hb_shaper_order_t
  59 {
  60   _HB_SHAPER_ORDER_ORDER_ZERO,
  61 #define HB_SHAPER_IMPLEMENT(Shaper) \
  62       HB_SHAPER_ORDER (Shaper),
  63 #include "hb-shaper-list.hh"
  64 #undef HB_SHAPER_IMPLEMENT
  65   _HB_SHAPERS_COUNT_PLUS_ONE,
  66   HB_SHAPERS_COUNT = _HB_SHAPERS_COUNT_PLUS_ONE - 1,
  67 };
  68 
  69 template <enum hb_shaper_order_t order, typename Object> struct hb_shaper_object_data_type_t;
  70 
  71 #define HB_SHAPER_DATA_SUCCEEDED ((void *) +1)
  72 #define HB_SHAPER_DATA_TYPE(shaper, object)             hb_##shaper##_##object##_data_t
  73 #define HB_SHAPER_DATA_CREATE_FUNC(shaper, object)      _hb_##shaper##_shaper_##object##_data_create
  74 #define HB_SHAPER_DATA_DESTROY_FUNC(shaper, object)     _hb_##shaper##_shaper_##object##_data_destroy
  75 
  76 #define HB_SHAPER_DATA_INSTANTIATE_SHAPERS(shaper, object) \
  77         \
  78         struct HB_SHAPER_DATA_TYPE (shaper, object); /* Type forward declaration. */ \
  79         extern "C" HB_INTERNAL HB_SHAPER_DATA_TYPE (shaper, object) * \
  80         HB_SHAPER_DATA_CREATE_FUNC (shaper, object) (hb_##object##_t *object); \
  81         extern "C" HB_INTERNAL void \
  82         HB_SHAPER_DATA_DESTROY_FUNC (shaper, object) (HB_SHAPER_DATA_TYPE (shaper, object) *shaper##_##object); \
  83         \
  84         template <> \
  85         struct hb_shaper_object_data_type_t<HB_SHAPER_ORDER (shaper), hb_##object##_t> \
  86         { \
  87           typedef HB_SHAPER_DATA_TYPE(shaper, object) value; \
  88         }; \
  89         \
  90         template <unsigned int WheresData> \
  91         struct hb_shaper_lazy_loader_t<hb_##object##_t, WheresData, HB_SHAPER_DATA_TYPE(shaper, object)> \
  92                 : hb_lazy_loader_t<HB_SHAPER_DATA_TYPE(shaper, object), \
  93                                    hb_shaper_lazy_loader_t<hb_##object##_t, \
  94                                                            WheresData, \
  95                                                            HB_SHAPER_DATA_TYPE(shaper, object)>, \
  96                                    hb_##object##_t, WheresData> \
  97         { \
  98           typedef HB_SHAPER_DATA_TYPE(shaper, object) Type; \
  99           static Type* create (hb_##object##_t *data) \
 100           { return HB_SHAPER_DATA_CREATE_FUNC (shaper, object) (data); } \
 101           static Type *get_null () { return nullptr; } \
 102           static void destroy (Type *p) { HB_SHAPER_DATA_DESTROY_FUNC (shaper, object) (p); } \
 103         }; \
 104         \
 105         static_assert (true, "") /* Require semicolon. */
 106 
 107 
 108 template <typename Object>
 109 struct hb_shaper_object_dataset_t
 110 {
 111   void init0 (Object *parent_data)
 112   {
 113     this->parent_data = parent_data;
 114 #define HB_SHAPER_IMPLEMENT(shaper) shaper.init0 ();
 115 #include "hb-shaper-list.hh"
 116 #undef HB_SHAPER_IMPLEMENT
 117   }
 118   void fini ()
 119   {
 120 #define HB_SHAPER_IMPLEMENT(shaper) shaper.fini ();
 121 #include "hb-shaper-list.hh"
 122 #undef HB_SHAPER_IMPLEMENT
 123   }
 124 
 125   Object *parent_data; /* MUST be JUST before the lazy loaders. */
 126 #define HB_SHAPER_IMPLEMENT(shaper) \
 127         hb_shaper_lazy_loader_t<Object, HB_SHAPER_ORDER(shaper), \
 128                                 typename hb_shaper_object_data_type_t<HB_SHAPER_ORDER(shaper), Object>::value \
 129                                > shaper;
 130 #include "hb-shaper-list.hh"
 131 #undef HB_SHAPER_IMPLEMENT
 132 };
 133 
 134 #endif /* HB_SHAPER_HH */