third_party/harfbuzz-ng/src/hb-shape-plan.cc

   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 #include "hb-shape-plan-private.hh"
  28 #include "hb-shaper-private.hh"
  29 #include "hb-font-private.hh"
  30 #include "hb-buffer-private.hh"
  31
  32 #define HB_SHAPER_IMPLEMENT(shaper) \
  33         HB_SHAPER_DATA_ENSURE_DECLARE(shaper, face) \
  34         HB_SHAPER_DATA_ENSURE_DECLARE(shaper, font)
  35 #include "hb-shaper-list.hh"
  36 #undef HB_SHAPER_IMPLEMENT
  37
  38
  39 static void
  40 hb_shape_plan_plan (hb_shape_plan_t    *shape_plan,
  41                     const hb_feature_t *user_features,
  42                     unsigned int        num_user_features,
  43                     const char * const *shaper_list)
  44 {
  45   const hb_shaper_pair_t *shapers = _hb_shapers_get ();
  46
  47 #define HB_SHAPER_PLAN(shaper) \
  48         HB_STMT_START { \
  49           if (hb_##shaper##_shaper_face_data_ensure (shape_plan->face)) { \
  50             HB_SHAPER_DATA (shaper, shape_plan) = \
  51               HB_SHAPER_DATA_CREATE_FUNC (shaper, shape_plan) (shape_plan, user_features, num_user_features); \
  52             shape_plan->shaper_func = _hb_##shaper##_shape; \
  53             shape_plan->shaper_name = #shaper; \
  54             return; \
  55           } \
  56         } HB_STMT_END
  57
  58   if (likely (!shaper_list)) {
  59     for (unsigned int i = 0; i < HB_SHAPERS_COUNT; i++)
  60       if (0)
  61         ;
  62 #define HB_SHAPER_IMPLEMENT(shaper) \
  63       else if (shapers[i].func == _hb_##shaper##_shape) \
  64         HB_SHAPER_PLAN (shaper);
  65 #include "hb-shaper-list.hh"
  66 #undef HB_SHAPER_IMPLEMENT
  67   } else {
  68     for (; *shaper_list; shaper_list++)
  69       if (0)
  70         ;
  71 #define HB_SHAPER_IMPLEMENT(shaper) \
  72       else if (0 == strcmp (*shaper_list, #shaper)) \
  73         HB_SHAPER_PLAN (shaper);
  74 #include "hb-shaper-list.hh"
  75 #undef HB_SHAPER_IMPLEMENT
  76   }
  77
  78 #undef HB_SHAPER_PLAN
  79 }
  80
  81
  82 /*
  83  * hb_shape_plan_t
  84  */
  85
  86 hb_shape_plan_t *
  87 hb_shape_plan_create (hb_face_t                     *face,
  88                       const hb_segment_properties_t *props,
  89                       const hb_feature_t            *user_features,
  90                       unsigned int                   num_user_features,
  91                       const char * const            *shaper_list)
  92 {
  93   assert (props->direction != HB_DIRECTION_INVALID);
  94
  95   hb_shape_plan_t *shape_plan;
  96
  97   if (unlikely (!face))
  98     face = hb_face_get_empty ();
  99   if (unlikely (!props || hb_object_is_inert (face)))
 100     return hb_shape_plan_get_empty ();
 101   if (!(shape_plan = hb_object_create<hb_shape_plan_t> ()))
 102     return hb_shape_plan_get_empty ();
 103
 104   hb_face_make_immutable (face);
 105   shape_plan->default_shaper_list = shaper_list == NULL;
 106   shape_plan->face = hb_face_reference (face);
 107   shape_plan->props = *props;
 108
 109   hb_shape_plan_plan (shape_plan, user_features, num_user_features, shaper_list);
 110
 111   return shape_plan;
 112 }
 113
 114 hb_shape_plan_t *
 115 hb_shape_plan_get_empty (void)
 116 {
 117   static const hb_shape_plan_t _hb_shape_plan_nil = {
 118     HB_OBJECT_HEADER_STATIC,
 119
 120     true, /* default_shaper_list */
 121     NULL, /* face */
 122     HB_SEGMENT_PROPERTIES_DEFAULT, /* props */
 123
 124     NULL, /* shaper_func */
 125     NULL, /* shaper_name */
 126
 127     {
 128 #define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INVALID,
 129 #include "hb-shaper-list.hh"
 130 #undef HB_SHAPER_IMPLEMENT
 131     }
 132   };
 133
 134   return const_cast<hb_shape_plan_t *> (&_hb_shape_plan_nil);
 135 }
 136
 137 hb_shape_plan_t *
 138 hb_shape_plan_reference (hb_shape_plan_t *shape_plan)
 139 {
 140   return hb_object_reference (shape_plan);
 141 }
 142
 143 void
 144 hb_shape_plan_destroy (hb_shape_plan_t *shape_plan)
 145 {
 146   if (!hb_object_destroy (shape_plan)) return;
 147
 148 #define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_DESTROY(shaper, shape_plan);
 149 #include "hb-shaper-list.hh"
 150 #undef HB_SHAPER_IMPLEMENT
 151
 152   hb_face_destroy (shape_plan->face);
 153
 154   free (shape_plan);
 155 }
 156
 157 hb_bool_t
 158 hb_shape_plan_set_user_data (hb_shape_plan_t    *shape_plan,
 159                              hb_user_data_key_t *key,
 160                              void *              data,
 161                              hb_destroy_func_t   destroy,
 162                              hb_bool_t           replace)
 163 {
 164   return hb_object_set_user_data (shape_plan, key, data, destroy, replace);
 165 }
 166
 167 void *
 168 hb_shape_plan_get_user_data (hb_shape_plan_t    *shape_plan,
 169                              hb_user_data_key_t *key)
 170 {
 171   return hb_object_get_user_data (shape_plan, key);
 172 }
 173
 174
 175 hb_bool_t
 176 hb_shape_plan_execute (hb_shape_plan_t    *shape_plan,
 177                        hb_font_t          *font,
 178                        hb_buffer_t        *buffer,
 179                        const hb_feature_t *features,
 180                        unsigned int        num_features)
 181 {
 182   if (unlikely (hb_object_is_inert (shape_plan) ||
 183                 hb_object_is_inert (font) ||
 184                 hb_object_is_inert (buffer)))
 185     return false;
 186
 187   assert (shape_plan->face == font->face);
 188   assert (hb_segment_properties_equal (&shape_plan->props, &buffer->props));
 189
 190 #define HB_SHAPER_EXECUTE(shaper) \
 191         HB_STMT_START { \
 192           return HB_SHAPER_DATA (shaper, shape_plan) && \
 193                  hb_##shaper##_shaper_font_data_ensure (font) && \
 194                  _hb_##shaper##_shape (shape_plan, font, buffer, features, num_features); \
 195         } HB_STMT_END
 196
 197   if (0)
 198     ;
 199 #define HB_SHAPER_IMPLEMENT(shaper) \
 200   else if (shape_plan->shaper_func == _hb_##shaper##_shape) \
 201     HB_SHAPER_EXECUTE (shaper);
 202 #include "hb-shaper-list.hh"
 203 #undef HB_SHAPER_IMPLEMENT
 204
 205 #undef HB_SHAPER_EXECUTE
 206
 207   return false;
 208 }
 209
 210
 211 /*
 212  * caching
 213  */
 214
 215 #if 0
 216 static unsigned int
 217 hb_shape_plan_hash (const hb_shape_plan_t *shape_plan)
 218 {
 219   return hb_segment_properties_hash (&shape_plan->props) +
 220          shape_plan->default_shaper_list ? 0 : (intptr_t) shape_plan->shaper_func;
 221 }
 222 #endif
 223
 224 /* TODO no user-feature caching for now. */
 225 struct hb_shape_plan_proposal_t
 226 {
 227   const hb_segment_properties_t  props;
 228   const char * const            *shaper_list;
 229   hb_shape_func_t               *shaper_func;
 230 };
 231
 232 static hb_bool_t
 233 hb_shape_plan_matches (const hb_shape_plan_t          *shape_plan,
 234                        const hb_shape_plan_proposal_t *proposal)
 235 {
 236   return hb_segment_properties_equal (&shape_plan->props, &proposal->props) &&
 237          ((shape_plan->default_shaper_list && proposal->shaper_list == NULL) ||
 238           (shape_plan->shaper_func == proposal->shaper_func));
 239 }
 240
 241 hb_shape_plan_t *
 242 hb_shape_plan_create_cached (hb_face_t                     *face,
 243                              const hb_segment_properties_t *props,
 244                              const hb_feature_t            *user_features,
 245                              unsigned int                   num_user_features,
 246                              const char * const            *shaper_list)
 247 {
 248   if (num_user_features)
 249     return hb_shape_plan_create (face, props, user_features, num_user_features, shaper_list);
 250
 251   hb_shape_plan_proposal_t proposal = {
 252     *props,
 253     shaper_list,
 254     NULL
 255   };
 256
 257   if (shaper_list) {
 258     /* Choose shaper.  Adapted from hb_shape_plan_plan(). */
 259 #define HB_SHAPER_PLAN(shaper) \
 260           HB_STMT_START { \
 261             if (hb_##shaper##_shaper_face_data_ensure (face)) \
 262               proposal.shaper_func = _hb_##shaper##_shape; \
 263           } HB_STMT_END
 264
 265     for (const char * const *shaper_item = shaper_list; *shaper_item; shaper_item++)
 266       if (0)
 267         ;
 268 #define HB_SHAPER_IMPLEMENT(shaper) \
 269       else if (0 == strcmp (*shaper_item, #shaper)) \
 270         HB_SHAPER_PLAN (shaper);
 271 #include "hb-shaper-list.hh"
 272 #undef HB_SHAPER_IMPLEMENT
 273
 274 #undef HB_SHAPER_PLAN
 275
 276     if (unlikely (!proposal.shaper_list))
 277       return hb_shape_plan_get_empty ();
 278   }
 279
 280
 281 retry:
 282   hb_face_t::plan_node_t *cached_plan_nodes = (hb_face_t::plan_node_t *) hb_atomic_ptr_get (&face->shape_plans);
 283   for (hb_face_t::plan_node_t *node = cached_plan_nodes; node; node = node->next)
 284     if (hb_shape_plan_matches (node->shape_plan, &proposal))
 285       return hb_shape_plan_reference (node->shape_plan);
 286
 287   /* Not found. */
 288
 289   hb_shape_plan_t *shape_plan = hb_shape_plan_create (face, props, user_features, num_user_features, shaper_list);
 290
 291   hb_face_t::plan_node_t *node = (hb_face_t::plan_node_t *) calloc (1, sizeof (hb_face_t::plan_node_t));
 292   if (unlikely (!node))
 293     return shape_plan;
 294
 295   node->shape_plan = shape_plan;
 296   node->next = cached_plan_nodes;
 297
 298   if (!hb_atomic_ptr_cmpexch (&face->shape_plans, cached_plan_nodes, node)) {
 299     hb_shape_plan_destroy (shape_plan);
 300     free (node);
 301     goto retry;
 302   }
 303
 304   /* Release our reference on face. */
 305   hb_face_destroy (face);
 306
 307   return hb_shape_plan_reference (shape_plan);
 308 }
 309
 310 const char *
 311 hb_shape_plan_get_shaper (hb_shape_plan_t *shape_plan)
 312 {
 313   return shape_plan->shaper_name;
 314 }